5431 5435.output

* GB785839 (A)
Description: GB785839 (A) ? 1957-11-06
Electric circuits including transistors
Description of GB785839 (A)
PATENT SPECIFICATION
Date of Application and filing Complete Specification: Dec 29, 1954.
785,839 No 37539/54.
) i Application made in United States of America on Dec 31, 1953.
Application made in United States of America on Dec 31, 1953.
, 7 Complete Specification Published: Nov6, 1957.
Index at Acceptance:-Class 40 ( 6), T.
International Classification:-H 03 f.
COMPLETE SPECIFICATION
Electric Circuits includi 2 Ag Transistors We, INTERNATIONAL BUSINESS
MACHINES Co R Po RAT Io N, a corporation organized and existing under
the laws of the State of New York, United States of America, of 590
Madison Avenue, New York 22, New York, United States of America, do
hereby declare the invention, for which we pray that a patent may be
granted to us, and the method by which it is to be performed, to be
particularly described in and by the following statement:-
This invention relates to transistor circuits, and particularly but
not necessarily exclusively to circuits handling pulse signals of
large magnitudes, power amplifying circuits, and impedance matching
circuits.
When transistors are used in circuits employing large signal pulses,
the transistors are in many cases operated in one of two stable output
states which are characterized by widely separated current and
potential conditions.
The output states are commonly described as the ON and OFF states, the
terms respectively defining high current and low current states.
The transistors are usually required to shift back and forth from one
state to the other quicldy in response to a relatively small input
signal.
A transistor may be described as a body of semi-conductive material

having an ohmic contact commonly referred to as a base electrode and
two asymmetric contacts commonly referred to as emitter and collector
electrodes The semi-conductive material is classified as either n-type
or p-type, depending upon whether the current carriers in it are
electrons or "holes".
The emitter electrode supplies to the semiconductive body minority
current carriers By minority carriers, it is meant that if the
semiconductive body is n-type, so thjat the normal current carriers in
it are electrons, then the emitter supplies "holes" On the other hand,
if the semiconductive body is p-type, then the emitter supplies
electrons Some of the minority carriers so supplied move to the
collector electrode The arrival of such lPrice carriers at the
collector electrode is accompanied by a release of excess or majority
carriers from the collector, flowing toward the base Under certain
conditions of transistor operation, specifically high collector
current 50 and low collector voltage, the collector is unable to
attract all the carriers supplied by the emitter, so that excess
minority carriers are stored in the base, and a further increment of
emitter current does not produce a corres 55 ponding increment of
collector current The transistor is then said to be saturated.
A given transistor can operate over a wide range of values of
collector current for each value of collector potential, depending
upon 60 the emitter current and the load impedance connected in its
output (usually its collector) circuit For a fixed linear load
impedance, however, there is only one value of collector current for
each value of collector potential 65 The locus of these values of
collector current on the collector current-potential plane is commonly
termed the load line For a linear impedance, the load line is
straight, and intersects the region of saturation The maximum 70 value
of collector current, for a fixed linear impedance occurs when the
transistor is saturated.
In large signal circuits of the prior art, it has been customary to
design the circuits to get 75 maximum current during the ON condition
of the transistor, so that the ON condition is a condition of
saturation In such a situation, when the transistor is shifted to its
OFF condition in response to an input signal, the col 83 lector
current does not immediately drop to its normal OFF value, but
decreases slowly until the accumulation of minority carriers which
characterizes the saturation condition has been cleared away The time
required for these 85 excess carriers to be cleared away is commonly
referred to as the "fall" time of the transistor.
A protracted fall time is undesirable, since it represents a period in
which the transistor is less sensitive than normal to incoming 90 r
signals.

It is furthermore found that the input variational impedance of a
conventional transistor circuit or stage varies non-linearly with the
input potential Variational impedance may be defined as the
differential rate of change of potential per unit change of current.
Typically, the variational impedance may vary with input potential
from a negative value to a positive value through an intermediate
range of input potentials where the variational impedance is
substantially infinite This infinite impedance range is very useful in
power amplifier and impedance matching stages, since a circuit
operated in that range has a constant loading effect on the preceding
stage However, in typical circuits, this high impedance is obtained
only over a very small range of input potential, so that it can be
used only for very small signals Moreover, the range of input
potentials in which this high impedance is obtained may shift because
of the inherent instabilities of present transistors Such a shift may
cause the circuit to appear as either a low positive or low negative
variational impedance load on the preceding stage In that event, it
either loads down the circuit, or in the case of a negative impedance,
tends to start an oscillation.
It has been suggested that the range of input potentials characterized
by infinite variational impedance may be widened by connecting a
resistor across the input terminals, thereby making the total input
impedance the sum of the transistor impedance and the resistor
impedance If the resistor is chosen to balance the negative input
resistance of the transistor then throughout the region where that
balance is effected, the total variational input impedance will appear
infinite.
However, since the slope of the negative impedance region is not
constant, it is impossible to balance it with a linear resistor over
any substantial proportion of its length Consequently, such circuits
have been limited as to the range of permissible variation of input
potentials.
We have now found that it is possible to influence both the "fall"
time and the input variational impedance by choice of load in the
collector circuit of a transistor stage and by the use of a composite
load impedance the characteristics of the stage may be arranged to be
different in different operating ranges.
According to the invention, we provide a transistor circuit including
a collector load impedance comprising an asymmetric unit, a source of
electrical energy and a resistance, said source being arranged to bias
said asymmetric unit so that the load impedance has at least two
different values assumed in response to corresponding ranges of
collector current.
In a particularly preferred embodiment of the invention, the load

impedance comprises two parallel branch circuits, one comprising a
resistor and a first source of electrical energy in series and the
other comprising a rectifier unit and a second source of electrical
energy in series.
The various features of the invention will be 70 better understood
from the following detailed description of preferred embodiments
thereof.
Reference will be made to the accompanying drawings, in which:Fig I is
a diagram of one form of transistor 75 circuit embodying the
invention; Fig 2 is a graphical illustration of a family of collector
current-potential characteristics for the circuit of Fig 1; Fig 3 is a
graphical illustration of an input 80 characteristic of the circuit of
Fig 1; Fig 4 is a diagram of a modified form of circuit embodying the
invention; Fig 5 is a graphical illustration of a family of collector
current-potential characteristics for 85 the circuit of Fig 4; Fig 6
is a diagram of a further form of circuit embodying the invention; Fig
7 shows graphically a family of collector current-potential
characteristics for the circuit 90 of Fig 6; and Fig 8 is a diagram of
yet another modified form of circuit embodying the invention.
Referring to Fig 1, there is shown a transistor I having a base
electrode lb, a collector 95 electrode lc and an emitter electrode le
The emitter electrode le is connected to ground through a resistor 2
Input terminals 3 and 4 are connected respectively to the base lb and
to ground Connected between the collector 100 electrode lc and ground
are two parallel branch circuits One of these branch circuits includes
a load resistor 5 and a battery 6 in series The other branch circuit
includes an asymmetric impedance unit 7 and a battery 8 in series Out
105 put terminals 9 and 10 are respectively connected to the collector
electrode Ic and to ground.
The battery 8 has a smaller potential than the battery 6 The resistor
5 is chosen so that the 110 potential drop across it when the
transistor is in its ON condition is greater than the difference
between the potentials of the batteries 6 and 8 With the asymmetric
unit 7 poled as shown in the drawing, the potential difference 115
across the asymmetric unit in the ON condition is in a direction to
send a current through it in its low impedance direction.
When the transistor is OFF, the potential drop across resistor 5 is
smaller than the dif 120 ference between the potentials of the
batteries 6 and 8, the potential difference across the asymmetric unit
7 is of the opposite polarity, and the flow of current through it is
substantially prevented 125 Fig 2 illustrates a family of collector
currentpotential characteristics for the transistor 1.
Each curve in Fig 2 is drawn for a fixed value of emitter current,
exemplary values of which are indicated by legend in the drawing There

130 785,839 must be substantially lower than the impedance of resistor
5, and its reverse impedance substantially higher.
If the foregoing conditions are met, then when the collector potential
is high, the 70 collector lc is more negative than the negative
terminal of battery 8, and consequently the potential across
asymmetric unit 7 is in the reverse direction, so that the current
flow through it may be neglected 75 As the collector potential
decreases, a value of current is reached where the potential drop
across resistor 5 just equals the difference of potential of the two
batteries 6 and 8 The collector-to-ground potential is then equal to
80 the potential of battery 8 There is then no potential across
asymmetrical unit 7 and no current flows through it As the collector
potential decreases beyond that value, the potential across the
asymmetric unit 7 reverses 85 in polarity, being then in the forward
direction with respect to that unit Further increments of collector
current flow through that unit rather than through resistor 5 because
of the lower impedance of the asymmetric unit 90 The total load line
for the circuit of Fig 1, for collector potential values lower than
Es, would be correctly shown by a line drawn through ordinates
representing the sums of the corresponding ordinates of curves 12 and
13 95 If asymmetric unit 7 and the potential of battery 8 are properly
selected, that total load line may be made to coincide substantially
with the right-hand linear portion of the curve 11 100 If the resistor
5, asymmetric unit 7 and the batteries 6 and 8 are selected as
indicated in Fig 2, then the input characteristic of this circuit will
have a form illustrated by the curve 14 in Fig 3, including a
substantial range 14 a, 105 where the input or base current Ib is
constant over a wide range of base potentials Vb, and the variational
impedance is substantially infinite.
The dotted line 15 in Fig 3, shows, for 110 purpose of comparison, the
appearance of the corresponding input characteristic of a conventional
transistor circuit.
FIGS 4 AND 5 The invention has been described above as 115 applied to
a transistor having a base input It is also applicable to transistors
having emitter inputs Fig 4 illustrates such a circuit, and Fig 5
illustrates graphically the collector current-potential
characteristics of the circuit 120 of Fig 4, with a superimposed load
line.
Referring to Fig 4, there is shown a transistor 16 having an emitter
electrode 16 e, a collector electrode 16 c and a base electrode 16 b
The emitter 16 e is connected to the grounded base 125 16 b through a
resistor 17 and a biasing battery 18 A pair of input terminals 19 and
20 are provided, the input terminal 19 being connected through a
capacitor 21 to the emitter electrode 16 e and the input terminal 20

being 130 is superimposed on this family of curves a curve 11,
represented in the drawing by a row of small circles The curve 11 is
drawn to represent a constant base current line That is, for each
point on the line 11, the algebraic sum of the corresponding values of
collector current and of emitter current is the same It will readily
be recognizedthatawhole familyof constant input current lines may be
drawn, one for each different value of constant current It may be seen
that the line 11 comprises two substantially straight portions
connected by a relatively sharp bend, the sharp bend being located at
the edge of the saturation region.
If a transistor having the family of characteristic curves illustrated
in Fig 2 is connected in a specific circuit, the locus of all the
possible operating points in the potential-current plane is defined by
a line commonly termed a load line When the only load is a linear
resistor, such as resistor 5, the load line is straight and the
impedance of the load determines the slope of the line The location of
the line may be determined by the fact that it passes through a point
corresponding to zero collector current and a collector potential
equal to the potential of the battery in the load circuit.
The line 12 in Fig 2 represents the load line determined by resistor 5
and battery 6 By properly selecting the resistor 5 and the potential E
6 of battery 6, a substantial portion of the load line 12 is made to
coincide with one of the substantially linear portions of the curve
11.
Line 13 in Fig 2 represents a similar load line determined by the
forward impedance of asymmetric unit 7 and the potential E 8 of
battery 8.
Both of the two branch circuits which respectively include resistor 5
and asymmetric impedance unit 7 are continuously connected between the
collector lc and ground Strictly speaking, therefore, the collector
current for any value of collector potential is the sum of the
currents through the two branches However, by connecting the two
branches in the manner shown, and by properly choosing the impedances
of resistor 5 and of asymmetric unit 7 in relation to the potentials
of the two batteries, the circuit may be arranged so that the
potential across asymmetric unit 7 is in the reverse direction during
the higher range of values of collector potentials and the current
flow through the asymmetric unit 7 may then be neglected.
In order to secure this relationship, the following conditions must be
met: battery 6 must have a higher potential than battery 8; the
impedance of resistor 5 must be such that the potential drop across it
is less than the difference between the two battery potentials when
the collector potential is high and greater than the difference
between the two battery potentials when the collector potential is

low; the forward impedance of asymetric unit 7 785,839 connected
directly to the grounded base 16 b.
Each curve in the family of collector potential current
characteristics appearing in Fig 5 is drawn for a constant value of
emitter current.
In the circuit of Fig 4, the emitter current and the input current are
the same Consequently, if the characteristics of the load impedance
are to be chosen to provide constant emitter current over a wide range
of input signal potentials, then the collector load impedance must be
selected so that the load line will follow one of the constant emitter
current lines Since the slope of the constant emitter current lines is
negative, the load impedance to be connected to the collector must
have a negative impedance, at least over a substantial range of
collector potentials The circuit of Fig 4 has therefore been provided
with a negative impedance load, comprising a transistor 22 Transistor
22 has an emitter electrode 22 e, a collector electrode 22 c and a
base electrode 22 b.
The load circuit for transistor 16 may be traced from the collector 16
c through a resistor 23, base electrode 22 b, collector electrode 22
c, and a battery 24 to the grounded base 16 b.
Emitter 22 e is connected through a resistor 25 to collector 16 c
Output terminals 26 and 27 are respectively connected to collector 16
c and to the grounded base 16 b.
A load line 28 is superimposed on the family of characteristic curves
in Fig 5 The intersection of load line 28 with the zero collector
current line is determined by the potential of battery 24 The contour
of load line 28 is determined by the characteristics of transistor 22
It may be seen that the load line 28 coincides with the line of
constant emitter current at 0 5 milliampere over a substantial range
indicated at 29 in the drawing.
The load line 28 is the voltage-current relationship existing between
terminals 26 and 27 as determined by transistor 22, resistor 23,
battery 24, and resistor 25 With low current through resistor 23, base
electrode 22 b and collector electrode 22 c, the potential at base
electrode 22 b is positive with respect to emitter electrode 22 e;
emitter electrode 22 e is held slightly negative with respect to
ground by the large negative bias on collector electrode 22 c which is
not completely isolated by the transistor 22 Therefore, emitter 22 e
is reversed biased and no forward emitter current flows in transistor
22 As current through resistor 23 increases, the potential of base
electrode 22 b becomes negative with respect to emitter electrode 22
e; thus the emitter of transistor 22 is biased in the forward
direction Forward emitter current flows and the current amplification
performed between the emitter and collector circuits of transistor 22

produces a greater current increase in the collector circuit of
transistor 22 which further increases the forward bias from emitter 22
e to base 22 b by the action of resistor 23 This positive feedback
mechanism will operate until saturation is reached in the collector
circuit of transistor 1 22 at which time the impedance from collector
22 c to base 22 b is quite low For this condition, the effective
impedance of the circuit including transistor 22 and resistor 23 is
quite low since a 70 small value of resistor 23 is adequte to produce
the regenerative feedback.
The parameters of the circuit of Fig 4 are quite critical, and both
transistors must be very stable for satisfactory operation 75 Any
input wave form may be used, within the limitations imposed by the
high frequency.
cut off of the particular transistor being used.
The circuits illustrated above are particularly useful as power
amplifier circuits and as im 80 pedance matching circuits In either
type of application, a wide range of input potentials may be received
at the input without changing the loading on the preceding stage The
output impedance of the circuit is quite low, which 85 makes the
circuit highly useful for connecting a high impedance output to a low
impedance input.
Referring to Fig 6, there is shown a transistor 1 having, a base
electrode lb, a collector 90 electrode lc and an emitter electrode le
This circuit is similar to that showvn in Fig 1 with the exception
that the emitter electrode le is connected to ground Input terminals 3
and 4 are connected respectively to the base lb 95 through resistor 32
and to ground Connected between the collector electrode lc and ground
are two parallel branch circuits One of these branch circuits includes
a load resistor 5 and a battery 6 in series The other branch circuit
100 includes an asymmetric impedance unit 7 and a battery 8 in series
Output terminals 9 and 10 are respectively connected to the collector
electrode lc and to ground.
The battery 8 has a smaller potential than 105 the battery 6 The
resistor 5 is chosen so that the potential drop across it when the
transistor is in its ON condition is greater than the difference
between the potentials on the batteries 6 and 8 With the asymmetric
unit 7 poled as 110 shown in the drawings, the potential difference
across the asymmetric unit in the ON condition is in a direction to
send a current through it in its low impedance direction.
When the transistor is OFF, the potential 115 drop across resistor 5
is smaller than the difference between the potentials of the batteries
6 and 8, the potential difference across the asymmetric unit 7 is of
the opposite polarity, and the flow of current through it is 120
substantially prevented.

Fig 7 illustrates a family of collector currentpotential
characteristics for the transistor 1.
Each curve in Fig 7 is drawn for a fixed value of emitter current,
exemplary values of which 125 are indicated by legend in the drawing
There is superimposed on this family of curves a load line 41,
representing the locus of all operating points of the transistor 1
when provided with a collector-base load circuit including only 130
785,839 of asymmetric unit 7 be as small as possible, so that load
line 42 will be as nearly vertical as possible.
The invention has been described above as applied to a transistor
having a base input It 70 is equally applicable to transistors having
emitter inputs Fig 8 illustrates such a circuit.
Since each of the circuit elements in Fig 8 is the substantial
equivalent of the corresponding element in Fig 6, the same reference
numerals 75 have been used In illustrating graphically the
characteristics of the circuit of Fig 8, each curve in the collector
potential current plane will be drawn for a constant value of base
current 80 The operation of the circuit of Fig 8 is considered to be
obvious from the foregoing description of the Fig 6 circuit, and it
will not be further described.
This invention is of value in any circuit 85 utilizing signals which
are on for appreciable lengths of time (i e, 3 or more microseconds).
Where signal pulses of 1 micro-second or less are used, few minority
carriers are stored because of the short times involved, and no 90
"fall" time problem arises.
The circuit shown as described is indicated as for a point contact
transistor of n-type semiconductive material It will readily be
recognized that the invention is equally applicable 95 to point
contact transistors of p-type material and to junction transistors.
Thus it will be seen that the invention may be applied to obtain
various desired characteristics in transistor circuits The description
100 has referred separately to two types of circuit, but it will be
understood that in other cases it may be desired to produce
preselected combinations of characteristics, and here also the
invention may be applied 105
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* GB785840 (A)
Description: GB785840 (A) ? 1957-11-06
Improvements in or relating to projectiles for whaling or like purposes
7855840 Date of Application and filing Complete Specification: Jan 11,
1955.
No 800/55.
Complete Specification Published: Nov 6, 1957.
Index at Acceptance:-Class 9 ( 1), A 2 (K: T).
International Classification:-FO 7 f.
Improvements in or relating to Projectiles for Whaling or like
purposes We, AIR WHALING LIMITED of 202 Bishopsgate London, E C 2 a
British Company and ALAN EDGAR BRISTOW of Henstridge Aerodrome,
Henstridge, Templecombe, Somerset, a British Subject do hereby declare
the invention, for which we pray that a patent may be granted to us,
and the method by which it is to be performed, to be particularly
described in and by the following statement:-
The present invention relates to projectiles primarily suitable for
the killing of whales and other large marine mammals or fish.
According to the invention a projectile comprises a first chamber for
storing a first fluid under pressure, a second chamber for storing a
second fluid separately from the first fluid, and means operable upon
penetration of the projectile in a surface for causing the second
fluid to be discharged from the forward end of the projectile by the
pressure of the first fluid.
In a preferred form suitable for killing whales and other large marine
mammals or fish, the first fluid comprises an anaesthetis or a killing
fluid and the second fluid an inflation fluid so that upon penetration
of the projectile into the body of a whale or other large marine
mammal or fish, the anaesthetising fluid is first discharged into the
body to anaesthetise the whale after which the inflating fluid is
discharged into the body to inflate the body and prevent the whale
from sinking.

Conveniently the said first chamber is formed by a hollow cylindrical
member or "gas bottle" adapted to contain an inflation gas in liquid
form and releasably secured between a front and a rear securing means
secured upon the respective ends of a tube extending axially through
the bottle, and the said second chamber is formed by an elongated
hollow cylindrical member or bodkin adapted to contain the
anaesthetising fluid and slidably disposed within the said axially
extending tube for movement from a collapsed position in which the
bodkin is substantially wholly contained within the tube, to an
extended position in which the lPrice 3 s 6 d l bodkin extends
forwardly from the tube and serves as a penetrating member for
penetrating into the body of the whale or like marine mammal The said
means for causing the discharge of the fluid conveniently comprise 50
thin walled tubes or "horns" extending transversely outwardly from the
front end of the bodkin and communicating with the interior thereof,
the said horns being of a fracturable material so that upon
penetration of the bodkin 55 into the body of the whale, the horns are
fractured and the fluid in the bodkin discharged into the body, means
being provided for communicating the interior of the bottle with the
interior of the bodkin when the bodkin is in 60 the extended position,
so that after discharge of the paralysing fluid from the bodkin, the
gas from the bottle is discharged through the bodkin into the body of
the whale to inflate the body and prevent it from sinking 65 The
bodkin is moved to the extended position after the firing of the
projectile, preferably just before the projectile strikes the body of
the whale.
The invention will now be described with 70 reference to the
accompanying drawings illustrating a whaling missile according to the
invention adapted to be fired from a spigot gun.
In the drawings:
Figure 1 is a longitudinal sectional elevation 75 of the missile in
the-unfired condition; Figure 2 is a section taken along the line
II-II of Figure 1; Figure 3 is a partial plan view looking in the
direction of the arrow III in Figure 2, and 80 Figure 4 is a view
similar to that of Figure 1 but showing the missile after firing and
in the discharged condition i e after penetration into the body of the
whale.
Referring to the drawings it will be seen that 85 the whaling missile
comprises a cylindrical vessel or gas bottle 1 adapted to contain an
inert gas such as for example carbon dioxide in liquid form which is
injected under pressure into the bottle through a charging valve 2 An
90 axial tube 3 extends longitudinally through the bottle rearwardly
through an aperture in the base of the bottle and forwardly through
the neck of the bottle The axial tube is screwthreaded at each end to

engage at its rear end in an end cap 4 provided with a part spherical
seating 5 for the base of the bottle, and its front end in a guide
tube 6 which engages a tapered sleeve 7 surrounding the neck of the
bottle It will be apparent that by screwing the axial tube into the
end cap 4 and then screwing the guide tube 6 on to the axial tube, the
bottle 1 is releasably secured between the end cap and the guide tube
The seating 5 of the end cap is grooved to receive a ring 8 of a
compressible material such as rubber lying proud of the groove so that
the base of the bottle is resiliently engaged in the seating.
An annular support 9 is gripped between the guide tube 6 and the
tapered sleeve 7 and serve to support a front fairing 10 having a
detachable nose 11.
The end cap 4 is provided with a screwthreaded bore 12 at its rear end
to receive one end of a tail tube 13 provided at its other end with a
clip 14 for attaching the missile to a spigot gun A firing pin 15 is
positioned between the front end of the tail tube 13 and the rear end
of the axial tube 3 and is adapted to be actuated by the spigot of the
gun.
Stabiliser fins 16 are secured on the rear end of the tail tube 13,
and a rear fairing 24 is gripped between a collar 25 on the tail tube
and the base of the bottle to enclose the end cap 4.
Slidably supported within the axial tube 3 is a tubular member or
bodkin 17 adapted to contain an anaesthetising fluid such as nitrous
oxide The bodkin 17 is sealed at its front end by a cap 18 and is
closed at its rear end by a piston 19 slidable therein, the said fluid
being contained between the cap 18 and the piston 19.
The cap 18 is provided with a pair of space forwardly extending lugs
20 which pivotally support therebetween two barbs 21 adapted to swing
from a rearwardly extending position as shown in Figure 1 to a
position extending at right angles to the bodkin 17 as shown in Figure
4 The wall of the bodkin 17 and that of the cap 18 are apertured as at
22 to receive one end of radially extending thin walled tubes or horns
23, the horns thus being in communication with the interior of the
bodkin 17 The horns are closed at their other end and are made of a
fracturable material so that upon the bodkin penetrating the body of a
whale as will be hereinafter described, the horns 23 are fractured to
permit the fluid contained in the bodkin to be discharged into the
body of the whale Conveniently the wall of each tube or horn 23 is
weakened adjacent the cap 18 as by forming a groove (not shown) in the
outer surface of the wall, to facilitate fracturing of the horn.
In order releasably to secure the bodkin in the retracted position
lying substantially wholly within the bottle 1 as shown in Figure 1
until the missile is to be fired, there is provided a safety pin
(Figures 2 and 3) in the form of a split pin 26 adapted to engage in

an aperture 27 in each of the lugs 20 and in apertures in a pair of
forwardly extending channel section mem 70 bers 28 secured at their
rear end as by welding, to the guide tube 6 The fairing nose 11 is
apertured as at 29 to permit the insertion and we ithdrawal of the
split pin 26, and as at 30 to permit the ends of the pin to be opened
out 75 after insertion through the members 28 and the lugs 20 Thus
when the pin 26 is inserted, the bodkin is releasably secured between
the channel members 28 secured to the guide tube 6 and is thereby
prevented from moving from 80 the retracted position Immediately prior
to firing the missile, the pin 26 is withdrawn and the bodkin is then
free to move forwardly as will -be hereinafter described.
At the rear end of the axial tube 3 there is 85 provided a cartridge
retainer 31 adapted to receive a cartridge 32 for expelling the bodkin
outwardly from the axial tube The cartridge 32 is provided with a slow
burning fuze which is ignited by the firing pin 15 upon the spigot go
of the gun striking the fixing pin when the inissile is fired from the
aforementioned spigot gun, so that the cartridge 32 does not fire
until after the missile has been fired from the gun.
Preferably the timing of the fuze of the car 95 tridge 32 is adjusted
so that the cartridge will fire just before the missile strikes the
whale.
Upon firing of the cartridge 32, the bodkin is forced forwardly by the
force exerted by the explosion on the piston 19 until a flange 33 at
100 the rear end of the bodkin engages an annular shoulder 34 at the
front end of the guide tube 6.
In this position, the piston 19 is maintained at the rear end of the
bodkin as shown in broken line at 19 ' in Figure 4, by the fluid
contained in 105 the bodkin.
The axial tube 3 is apertured as at 35 (Figure 4) forwardly and
rearwvardly within the bottle 1, the apertures 35 being closed by
tapered plugs 36 (Figure 1) adapted to be blown out by the 110 firing
of the bodkin cartridge 32 so that when the bodkin is in the forwardly
extended position as shown in Figure 4, the gas under pressure in the
bottle passes through the apertures 35 into the axial tube behind the
bodkin and exerts a 115 force on the piston 191 to maintain the bodkin
in the forward position.
In an alternative arrangement, the blow-out plugs 36 are replaced by
slide valve adapted to be actuated when the bodkin is expelled for 120
wardly from the axial tube to communicate the interior of the bottle 1
with the interior of the axial tube 3.
When the bodkin penetrates the body of the whale, the horns 23 are
fractured and under the 125 pressure of the gas from the bottle 1, the
piston 191 discharges the fluid in the bodkin through the apertures 22
and the fractured horns 23 into the whale, the piston then occupying

the position indicated at 191 " in Figure 4 in which 130 785,840 2 A
projectile for killing whales and other marine mammals or fish
comprising a first chamber for storing a fluid such as an
anaesthetising fluid, a second chamber for storing a gas under
pressure and separately from said 70 fluid, and means operable upon
penetration of the projectile into the body of a whale or like large
fish-like mammal, for causing the gas to discharge the fluid and then
to be discharged itself from the projectile forwardly thereof, 75
whereby the whale or like large fish-like mammal is anaesthetised by
the fluid and its body inflated by the gas.
3 A projectile according to claim 2 wherein the said operable means
includes a fracturable 80 member adapted to be fractured upon
penetration of the projectile into the body of the whale or like large
fish-like mammal thereby to permit the fluid and the gas to be
discharged into the body 85 4 A projectile for killing whales or other
marine mammals or fish comprising a cylindrical vessel adapted to
contain a fluid, a tubular member adapted to contain a fluid such as a
paralysing fluid and slidable in the 90 said cylindrical vessel
longitudinally thereof from a retracted position lying substantially
wholly within the said vessel to a position extending outwardly
forwardly therefrom, and a fracturable tube or horn extending trans 95
versely outwardly from the front end of the.
said tubular member in communication with the interior thereof whereby
upon penetration of the said front end in the body of a whale or like
large fish-like mammal, the said horn is 100 fractured to permit the
fluid to be discharged from the tubular member into the said body.
A projectile according to claim 4 wherein the said cylindrical vessel
comprises a gas bottle having an axial tube extending lon 105
gitudinally therethrough and said tubular member or bodkin is slidably
supported in the said axial tube, means being provided for ejecting
the said bodkin forwardly of the axial tube from the retracted
position lying substantially wholly 110 within the axial tube to the
extended position of the bodkin the said means being adapted to
operate after the projectile has been fired.
6 A projectile according to claim 5 wherein the said bodkin ejecting
means operates to eject 115 the bodkin to the forwardly extending
position just prior to the projectile striking the body of the whale
or like large fish-like mammal.
7 A projectile according to claim 5 or 6 provided with means for
communicating the 120 interior of the bottle with the interior of the
axial tube upon ejection of the bodkin outwardly from the axial tube
and the bodkin is closed at its rear end by a piston slidable therein
whereby the gas acts on the piston to eject the 125 fluid from the
bodkin upon fracturing of the said fracturable tube or horn.

8 A projectile according to claim 7 wherein the said bodkin ejecting
means comprises a cartridge having a slow burning fuze adapted 130 as
will be seen the apertures 22 are uncovered to permit the gas in the
bottle to discharge through the horns into the body of the whale.
In firing the missile, the missile is attached in known manner by
means of the clip 14 to a spigot gun The safety pin 26 and the fairing
nose 11 are then removed and the gun fired.
At a predetermined time, governed by the slow burning fuze of the
cartridge 32, after leaving the gun, the cartridge 32 fires to expel
the bodkin forwardly to the extended position of Figure 4, the piston
remaining in the rear position 191 and the plugs 36 blowing out to
admit gas into the axial tube 3 Upon the bodkin penetrating the body
of a whale, the horns 23 are fractured and the fluid in the bodkin is
discharged into the whale, followed by the gas from the bottle 1 as
above described.
The whale is thus first anaesthetised by the fluid from the bodkin
after which its body is inflated by the gas from the bottle 1 to
prevent the body from sinking.
It will be apparent that the above described construction provides a
whaling missile in which an anaesthetising fluid and an inflation gas
are stored in separate chambers i e the bodkin 17 and the bottle 1
respectively, until required for use and that the said fluid and gas
are automatically released upon the missile striking the body of a
whale.
It will likewise be apparent that means other than the slow acting
cartridge 32 may be employed to eject the bodkin after the firing of
the missile For example mechanical means may be employed which eject
the bodkin as soon as the front of the bodkin i e the lugs 20 make
contact with the body of the whale, or electrically actuated means
which become operative when the missile is within a predetermined
distance from the whale, may be provided for ejecting the bodkin.
The missile may also be provided with means for connecting an electric
cable thereto as described in the Specification of our co-pending
Application No 799155 so that at the moment of penetration of the
missile into the body of a whale, a heavy electric shock is imparted
to the whale.
In the specification of our co-pending application No 798155 there is
described and claimed a missile suitable for inflating whales and
other bodies, comprising a chamber adapted to contain a gas under
pressure and means including a hollow member fracturable upon
punctuation of the missile into the body for discharging the gas into
the body.
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* GB785841 (A)
Description: GB785841 (A) ? 1957-11-06
A multi-step escapement device for typewriters
A high quality text as facsimile in your desired language may be available
amongst the following family members:
DE944315 (C) FR1129431 (A) US2794530 (A)
DE944315 (C) FR1129431 (A) US2794530 (A) less
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The EPO does not accept any responsibility for the accuracy of data
and information originating from other authorities than the EPO; in
particular, the EPO does not guarantee that they are complete,
up-to-date or fit for specific purposes.
Inventor: REINHOLD LIEBMANN 70 Date of Application and filing Complete
Specification: Feb 7, 1955.
No 3564/55.
Index at acceptance: -Class 100 ( 4), C 2 OG 1 (A: B).
International Classification:-B 41 j.
A Multi-Step Escapement Device for Typewriters We, OLYMPIA WERKE A G,
of Wilhelmshaven, Germany, a German Company, do hereby declare the

invention, for which we pray that a patent may be granted to us, and
the method by which it is to be performed, to be particularly
described in and by the following statement: -
The invention relates to typewriters and is particularly concerned
with a multi-step escapement device for differing letter steps so as
to make possible proportional letter spacing or to provide differing
spacings often required for unusual scripts.
It is the object of the invention to devise an escapement device for
the above mentioned purposes which is simple in its design and
reliable in service The escapement device according to the invention
is characterised in that ( 1) it comprises a rotatably mounted
cylindrical drum which has an annular cavity to accommodate a row of
balls, and a number of bores which extend in an axial direction from
the rear wall of the said annular cavity to the rear end face of the
drum, the distance between the axes of two adjacent bores
substantially corresponds to a multiple of the diameter of a ball, and
the opening into each bore from the said annular cavity is to some
extent smaller than the diameter of a ball, but big enough to allow a
ball to enter partly into the opening, ( 2) that each bore
accommodates a plungerlike actuating pin which is biased by a return
spring to stay normally within the bore so as to prevent the ball from
entering the opening in the bore, but can be forced by a ball against
the action of the said spring to move backwards so as to project from
the rear end face of the escapement drum, ( 3) that the front wall of
the said annular cavity has a number of holes each coaxially with one
of the openings in the opposite wall of the annular cavity, ( 4) that
a spring loaded tappet extends into each hole so that its end is
normally flush with the interior surface of the wall of the cavity, (
5) that two sets of unilPrice 3 s 6 d l 55,84 1 versal bars are
provided for typing in the lower case and in the upper case
respectively, the number of universal bars in each set corresponding
to the number of tappets, and 50 each of the universal bars actuating
one of the tappets, ( 6) that a stop carrier is mounted so that its
stop extends in the range of the actuating pin, ( 7) that the number
of balls is such that always one ball is locked by the 55 row of the
other balls in a position where it penetrates into one of the opening
of the said bores to shift an actuating pin out of its bore against
the action of its, return spring, and that such a ball is returned
into the row 60 of balls by the returning actuating pin when another
ball is forced by a tappet into -the opening of another bore, and ( 8)
that the escapement drum is coupled by means of a clutch to a
transmission gearing to convert 65 its rotary movement into the
lengthwise movement of the typewriter carriage If four tappets are
used which are actuated by four universal bars in each case (upper and

lower), four different letter spacing steps are ob 70 tained.
In order that the invention may be clearly understood an embodiment
thereof will now be described by way of example with reference to the
accompanying drawings, wherein 75 Fig 1 illustrates a cross-section
through the whole actuating mechanism, Fig 2 is a plan view of the
escapement drum with the ball lock, Fig 3 represents a section through
the 80 escapement drum along the line A-A of Fig 2, Fig 4 represents a
section through the escapement drum along the line B-B of Fig 2, 85
Fig 5 is a perspective representation of the control device with two
groups of universal bars, Fig 6 shows a plan view of the bearing
carrier, and 90 Fig 7 is a plan view of the stop member.
At the rear part of the frame of the typewriter, as viewed by the
typist, two transverse plates 1 and 2 are provided A bearing carrier 3
is fastened by means of screws to the transverse plate 2, which
carrier serves for the support of one end of a shaft 4, the other end
of which being supported in the other transverse wall 1; the shaft 4
carries an escapement drum 5 and a pinion 6 adapted to be displaced a
small distance in an axial direction The bearing carrier 3 has an
annular cavity 3 a into which a stop carrier 7 extends, the latter
being held in its position by a screw cap 8 In the annular cavity 3 a
of the bearing carrier 3 also a ring shaped spring 9 is provided which
urges resiliently the stop carrier 7 against the flange of the screw
cap 8 and thus keeps the stop carrier in its postiion The screw cap 8
is locked in its position by a grub screw 10, and is thus secured
against inadvertent rotation A counter shaft 11 is mounted between the
two transverse walls 1 and 2 and extends parallel to the shaft 4 A
gear 12 is fastened to the counter shaft 11, which gear engages the
pinion 6 A pinion 13 which is fast on the shaft 11 engages the feed
rack 14 of the paper carriage not shown in the drawing.
The shaft 4 is provided with a collar 4 a which fits into a recess Sa
of the hub of the escapement drum so that the hub bears against the
collar, and the shaft 4 is provided in addition with a screw thread 5
b at its end facing the bearing carrier A nut 15 serves for securing
the escapement drum 5 on the shaft and for holding together the two
parts of which the escapement drum consists, i e an actuating pin
carrier 5 c and a ball carrier Sd, both will be described hereinafter
in more detail The nut 15 is secured against inadvertent loosening by
means of a safety sheet metal clip 16.
The ball carrier 5 d is so disposed within a recess of the actuating
pin carrier Sc that a free annular space is formed for accommodating
the ring of balls 17 which act as a ball lock This space is so
dimensioned that one ball lies about half its diameter beyond the ball
ring The actuating pin carrier 5 c is provided over an annular surface
with bores 18 adapted to receive the actuating Dins 19.

In order to obtain a reliable operation of the ball lock, small
friction, and favourable dimensions of the escapement drum 5, the
number of balls 17 is double the number of co-acting actuating pins 19
The bores 18 are so dimensioned that they have a larger diameter where
they face the ball ring 17 than at their outer ends Each actuating pin
19 is provided with a collar 19 a which has such a diameter that it
just fits into the bore 18 of the actuating pin carrier 5 c The collar
19 a serves asa bearing for a spiral pressure spring 20 which bears
with its other end against the wall of the actuating Din carrier Sc;
the springs 20 are provided for maintaining the actuating pins 19 in
their normal position The axially elongated hub of the actuating pin
carrier 5 c is shaped in the represented example to form one clutch
member 21 of a tooth clutch The outer surface 70 of the actuating pin
carrier Sc is provided with a certain number of teeth 22.
The stop carrier 7 is provided at its upper rim with a ring 7 a
consisting of artificial rubber against which a stop member 7 b of 75
sheet metal resiliently bears The stop carrier 7 is provided at its
circumference with an annular groove 7 c adapted to receive a pawl 23
The pawl 23 is pivotally supported about a pin 24 (Fig 2) and is
biased with its 80 point against the teeth 22 of the escapement drum 5
by the action of a spring 25.
The pinion 6 has, where it faces the escapement drum, an axial
projection 6 a provided with teeth which forms the other clutch 85
member co-acting with the clutch member of the escapement drum 5 (Fig
1) At the circumference of the projection 6 a, an annular groove 6 b
is provided which is engaged by an actuating member 26 adapted to be
operated 90 by a release device not shown in the drawing.
By means of the control member 26 it is possible to cause the pinion 6
to engage or to disengage the escapement drum 5.
At the front face of the bearing carrier 3 95 (Fig 6) five ribs 27 are
provided, and in each interspace between two ribs a transmission lever
28 is pivotally mounted about a stationary pin 29 (Fig 3) Each
transmission lever 28 has a small cam 28 a where it faces the 100
bearing carrier 3 and at its opposite side a finger 28 b The fingers
28 b as well as the cams 28 a of the individual levers, are arranged
substantially on the same circle In the lower part of the bearing
carrier 3 four 105 bores 30 are provided which accommodate tappets 31
biased by springs 32 The distance of each tappet 31 from the centre
point of the bearing carrier 3 corresponds to the distance from the
centre of the shaft 4 to the 110 ball-lock.
The tappets 31 are pressed by means of spiral pressure springs 32
against the cams 28 a of the transmission levers 28, so that the
latter are caused to rock against a stop 115 formed by a pin 33
threaded through all the ribs 27, and the said levers bear against the

pin when they are in their normal position.
The control of the transmission levers 28 is effected by specially
designed universal 120 bars 34, of which two groups are provided, i.e
one group 34 a for typing in the lower case and another group 34 b for
typing in the upper case, see Fig 5.
In the represented example each group 125 comprises four universal
bars, each of which has at the end which faces the transmission levers
28, an actuating finger 35 so disposed that one finger 35 is arranged
opposite to one transmission lever 28 The universal-bar 130 785,841
ring 17, is free to return into the row of balls.
The return movement of this ball is effected by the tensioned pressure
spring 20, disposed behind the associated actuating pin 19, and also
this pin is caused to return into its rest 70 position As a result of
these actions, on the one hand, the actuating pin 19, which has been
shifted outwards by means of the tappet 31 and the corresponding ball
of the balllock 17 is now locked in its new position, and 75 on the
other hand, the escapement drum 5 has been released to rotate until
the projecting new actuating pin 19 contacts the stop plate 7 b of the
stop carrier 7 The angle through which the escapement drum 5 rotates,
80 is at the same time a measure for the movement of the paper
carriage, and the transmission through the pinion 6, the co-acting
gear 12 to the pinion 13 and the feed rack 14 is so chosen that a
certain fraction of one re 85 volution of the escapement drum 5
corresponds to a stepping unit of the carriage.
Each character is associated according to its width with a universal
bar, which selects one of the oppositely disposed transmission 90
levers 28 and the corresponding ball of the ball-lock 17 and actuating
pin 19 so that the now projecting actuating pin 19 moves to the stop
through an arc which corresponds to the width of the character with
the result that 95 each escapement stop is determined by the width of
the character.
On return of the carriage, it must be avoided that the escapement drum
5 rotates in an opposite direction, otherwise it would 100 not be
possible to determine exactly the beginning of each line Therefore,
the pawl 23 has been provided which arrests the escapement drum 5 when
the paper carriage is returned However, the spring 25 which acts 105
upon the pawl 23 must exert only a small pressure in order not to
interfere with the typing operation.
When the carriage is returned to its initial position, the control
device 26 causes the 110 pinion 6 to disengage the escapement drum 5,
so that the gears 6, 12, 13 are free to rotate and the return of the
carriage can be easily performed without disturbing noise.
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* GB785842 (A)
Description: GB785842 (A)
No title available
Date of Application and filing Complete Specification: Feb 8, 1955.
Application made in France on Feb 13, 1954.
785,842 No 3676/55.
Index at Acceptance:-Class 104 ( 3), A 1 D 6, A 2 (A 4: A 7 D 2: B 3).
International Classification:-B 61 m.
Three-Wire Traction System for Trolleybuses I, JEAN JACQUEMOND, of 6,
rue Borghese, Neuilly sur Seine, France, of French nationality, do
hereby declare the invention, for which I pray that a patent may be
granted to me, and the method by which it is to be performed, to be
particularly described in and by the following statement:-
The invention relates to a three wire distribution system with direct
or alternating current for trolley vehicles or the like.
According to the invention the supply line comprises a pair of
parallel spaced power conductors in the same horizontal plane
characterised in that the third conductor is spatially disposed above
said pair of conductors.
According to a further development of the invention for current
collection, use is made of a single three-pole current collector, the
arrangement of which more particularly forms part of this invention
and the construction of which is facilitated by the closeness and
reduced sag of the three wires forming the catenary contact line.

At crossings and junctions of the three-pole contact line it is
possible to use three-pole collector devices such that at the actual
crossing or junction point only the third centre wire remains in
operation to guide the corresponding pole of the single collector, the
two lateral wires being interrupted or raised above the level of the
apparatus so that they can no longer be used at the said crossing or
junction points by the corresponding contacts on the current
collector, which contacts are arranged to be lower than the third
contact so as to pass below the same at a crossing point.
Other features of the invention will emerge from the detailed
description to be given hereinafter.
An embodiment of the traction system devices according to the
invention is illustrated by way of example in the accompanying
drawings.
In the drawings:
Figure 1 is a perspective of a catenarylPrice 3 s 6 d l mounted
three-pole contact line; Figure 2 is a side elevation of the wire
suspension system; Figures 3 and 4 are cross-sectional and plan views,
respectively, of the three-pole collector; 50 and Figures 5 and 6 are
a vertical sectional and inverted plan view, respectively, of a
three-line crossing.
The three-pole catenary line of Figure 1 has 55 its supporting cable 1
supported directly without insulation, for example, by brackets 2
fixed to posts 3, the brackets being earthed either directly by the
posts, if the same are conductive or through an earthing connection 4
60 The neutral wire 5 is hung directly on the supporting cable by
hangers 6 which thus permanently earth the neutral wire through the
supporting cable and brackets The neutral wire 5 can be formed either
by a con 65 ventional conductor wire or by a slightly less conductive
wire or rail made, for example, of steel, the conductivity of the
supporting cable 1 being added to the conductivity of the neutral wire
5 70 The two live wires 7 and 8, which are at the voltages +U/2 and
-U/2 respectively, are supported so as to extend parallel with the
neutral wire and on each side thereof, and are insulated therefrom at
suspension points by 75 fittings 9 The equipment is retained at post
level by an anti-swing stay 10.
The arrangement supporting the three conductors is formed (Figure 2)
by: a member 11 suspended on the supporting cable 1 by the 80 hanger,
which latter is formed by two wire pieces 6 and 6 ', the arrangement
thereby being given transverse stability.
The neutral wire 5 is suspended directly on the member 11 through the
agency of claws 12 85 The two live wires 7 and 8 are supported one on
each side of the member 11 by an insulated bar 13 which is fast with
the member 11 and which has at each end insulators 14 and 15

supporting the wires 7 and 8 through the 90 agency of claws 16 and 17
In this way the live wires 7 and 8 are doubly insulated from one
another and from the neutral, which latter is earthed directly via its
suspension.
The arrangement is contrived so that the two live wires 7, 8 are at a
lower level than the neutral wire 5.
If an anti-swing stay is fitted, the bar 13 is extended at 13 ' and
joined to the anti-swing stay 10 by an arm 18.
This catenary arrangement between each post is retained on
large-radius curves, by reducing the distances between the posts 3
arranged around the radius of curvature.
On small-radius curves and, in cases where a catenary suspension
cannot be used, for instance on routes through towns, the threewires
of the three-pole line are directly supported by means of cross-pieces
in the same manner as conventional two-pole trolleybus wires The
slight separation between the wires in such an arrangement is
maintained if necessary, by means of insulated spacing bars.
Connedtion between the motors of the vehicle and the live and neutral
wire is effected, according to the invention through the agency of a
single three-pole collector.
The latter is illustrated in Figures 3 and 4 and is formed by a head
19 articulated through a ball and socket joint 20 to the end of a
vertical rod 21 borne by the arm 22 of the trolley bar 22 ' The
latter, is fitted to the vehicle and comprises the vertical rotating
rod and compression springs which are conventional in this kind of
apparatus.
The single three-pole collector is preferably arranged on the off-side
of the vehicle corresponding to the direction of movement, in order to
reduce by half the vehicle width the overhang of the contact line on
the road when the said line is a two-way one, this being the most
usual case.
Two slide-bars 24 bear against the rod 21 and maintain parallel
thereto the central plane of the head.
Preferably the head 19 is insulated from the trolley bar 22 ' by the
interposition of an insulated sleeve 23.
The top of the head 19 has contact means such, for example, as a shoe
25 which is held between two cheeks 26 and which bears against the
neutral wire 5 in the manner conventional in trolleybus collector
shoes The shoe 25 is disposed forwardly of the axis of the ball joint
21 as seen in the direction of travel.
The cheeks 26 are rearwardly extended by higher and more widely
separated cheeks 27.
The head 19 has two laterally disposed insulated flanges 28 to which
are articulated lateral arms 29 and 30 which contact the two live

wires 7 and 8 by way of shoes 31 and 32.
Each lateral collector is formed by an arm 33 which bears a shoe 31
rotating about a stationary pin 34 on the insulated cheek 28 with the
interposition of flexible articulation 35 which enables the lateral
collector to deflect slightly in all directions and which can be
formed, for example, by a rubber sleeve.
The arm 33 is urged upwardly by a spring 36, the upward movement of
the arm 33 being 70 limited by a stop 37.
The lateral collectors are connected by flexible cables 38 and 39 to
terminals 40 and 41, respectively, which are fitted to the sleeve 23
and are thus connected through insulated 75 cables 42 and 43 to the
trolleybus equipment.
The head 19 is connected to the neutral wire of the trolleybus
equipment by the insulated cable 44.
According to these arrangements, the head 80 19 is urged upwardly
along the ball joint axis by a force F resulting from the springs of
the vehicle-mounted current collector base This force F is distributed
between the three shoes 25, 31 and 32, a pressure Po being exerted on
85 the neutral wire and a pressure Pl being exerted on each of the two
lateral wires, the pressure Pl being determined by the calibration of
the spring 36 To keep the assembly balanced the centre of the ball
joint 20 is 90 placed at the centre of pressure of these pressure
points.
The head of the current collector is constantly guided along the
neutral wire by the cheeks 26 of the shoe 25, the articulation of the
95 ball joint permitting all the necessary movement of the collector
relatively to the wire in all inclinations, although the slide bars 24
keep the collector in a vertical plane.
The friction forces exerted by the wires 100 upon the two lateral
shoes disposed rearwardly of the central shoe ensure that the head is
stable in the direction of travel.
In its movements the head 19 moves the lateral collectors 29 and 30,
the shoes 31 and 32 105 of which are not guided but are wide enough to
maintain permanent contact, notwithstanding slight differences in
positions of the wires with respect to one another, while the
resilient articulation 35 of the arms relatively to the head 110 19
absorbs vibrations and slight transient lateral relative movements of
the lines.
The line equipment such as crossings, junctions and divisions into
sections are formed in the following way, the description relating 115
by way of example to the embodiment of a crossing as shown in Figures
5 and 6.
Two lines, the first of which comprises the neutral conductor 5 and
the live conductors 7 and 8, and the second of which comprises the 120

neutral conductor 5 ' and the live conductors 7 ' and 8 ', cross
without any conductor discontinuity.
The plate 45 of the crossing is secured without insulation below the
neutral conductors 5 125 and 5 ' by stirrup shaped members 46.
The lower part of the plate 45 comprises two spout-shaped members 47
and 47 ' which extend each line and which cross at the centre, the
latter being marked by a guiding projection 130 785,842 It is obvious
that other embodiments and other variants can be constructed without
altering the principle of the invention For example, the collector
shoes can be replaced by rollers, and at crossings and junctions the
70 lateral live wires, instead of passing above the apparatus, after
having been insulated, can be interrupted on either side.
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* GB785843 (A)
Description: GB785843 (A) ? 1957-11-06
Reading device for characters represented on a plate in micro-reproduction
Date of Application and filing Complete Specification: Feb 25, 1955.
Application made in Germany on May 21, 1954.
Application made in Germany on Sept 13, 1954.
Application made in Germany on Jan 25, 1955.
785,843 No 7574/55.
Index at Acceptance:-Class 97 ( 1), J 21 A.
International Classification:-GO 2 d.

Reading Device for characters represented on a plate in
Micro-Reproduction We, THEODOR KXRNER, of K Caiser-WilhelmStrasse 5 c,
Starnberg/See, Germany, and WILHELM FRIEDRICH POHL, Leutzestrasse 59,
Schwabisch Gmiind, Germany, both citizens of the Federal Republic of
Germany, do hereby declare the invention, for which we pray that a
patent may be granted to us, and the method by which it is to be
performed, to be particularly described in and by the following
statement:-
This invention relates to a device for reading characters represented
in micro-reproduction on both faces of a plate, with the aid of a
microscope.
When working frequently with reference works, tables, time-tables and
the like or when being compelled to use dictionaries for reading texts
in a foreign language when travelling abroad, it is always felt to be
annoying to turn the leaves of a dictionary however small and handy it
may be This fact in many cases paralyses the pleasure of reading
literature and of making conversation in a foreign language.
In a similar way difficulties are encountered in reading archive
material preserved according to the recent practice by
micro-reproduction which in general is made readable by magnifying it
with a projector This, however, requires in any case the use of an
additional comparatively voluminous apparatus.
To obviate these disadvantages we have developed a reading device
which makes looking up in reference works or the like quick and easy
and possible with one hand only.
Our reading device may be manufactured with any desired dimensions
from pocket size up to the dimensions of a desk plate The invention
utilises the known micro-reproduction of characters on a plate which
can be read by means of a reading device In the device according to
the invention the microscope is movable along a member or members
extending over both faces of said plate and serving to support said
microscope so that it is prevented from becoming detached from said
plate, and whereinthere are embodied in, or associated lPr with, the
said member or members means for enabling the microscope to be moved
to any part of each face of said plate The said member or members may
include a rigid U-shaped yoke member serving as, or provided with,
guide 50 means for a runner which carries the microscope The U-shaped
yoke member may be provided with guide means such as slots or grooves
for the runner Where the U-shaped member consists of two rails between
which 55 the runner slides the slots or grooves are formed on the
internal sides of such rails in such a manner as to permit sliding
engagement with guiding pins on the runner The runner may be provided
with side extensions such as 60 small leaf springs in frictional
engagement with flanges on the U-shaped member and serving to hold it

relatively to the U-shaped member in its position of rest Instead of a
rigid U-shaped member, extensible resilient strings may be 65 provided
surrounding both faces of the plate and enabling the microscope to be
moved over both faces of the plate For this purpose a runner carrying
the microscope may have eyes, holes or the like by which strings are
guided 70 In order to be able to move the microscope also over larger
areas for which the extensibility of the strings is not sufficient,
sliders may be provided which are slidable on the edges of the plate
and embrace the margins with their legs 75 and which have holes or
eyes for the strings.
The co-operative connection of the microscope with the U-shaped member
may be also in the form of a magnetic coupling by using permanent
magnets for the runner or for the 80 M-shaped member or for both If
desired, one or a plurality of ferromagnetic or non-ferromagnetic
intermediate members may be arranged between the runner and the
Ushaped member which intermediate members, 85 if ferro-magnetic,
likewise may be made permanent magnets To prevent lateral sliding off
of the lens runner, guiding grooves or profiled guiding rails may be
provided on the U-shaped member which are capable of being 90 engaged
by projections or flanges on the runner.
The micro-reproduction may either be applied on both faces of a plate
in general by a photochemical procedure or the microreproduction may
be on foils which are subsequently applied to both faces of the plate.
The plates may have a circular or a polygonal preferably, however, a
circular or a rectangular configuration.
If circular plates are used they are rotatable about an axis For this
purpose each plate may be provided with a hole so as to be rotatable
about a pivot In order to be able to exchange the plates in a quick
and simple manner the pivot is secured by a screw which can easily be
loosened A particularly simple arrangement is obtained if the same
pivot is used to hold the two legs of the yoke member Under certain
circumstances it may be convenient to provide on the pivot of the
plate a rotatable winding up spring and in addition to provide on the
yoke member brake means for the rotating plate.
The edge of the plate may be knurled to obtain a better grip if the
plate is to be manually rotated or braked.
Similarly as with the embodiment using a circular plate the
micro-reproduction may be placed between two rectangular sheets the
edges of which are embraced at least at two edges by preferably
detachable clamps in particular by frame members acting as clamps of
which one is connected with guiding means for a slider to which the
U-shaped yoke member is attached The clamps or frame member may be
secured to two opposite edges of the sheet but may be arranged also on
three adjacent edges of the plate in particular in such a manner that

a continuous frame acting as a clamp embraces the sheets at three
edges at least partially.
This frame member may be U-shaped both as to its general configuration
and in its crosssection At the clamps or frame member the sheets may
be held together by screws, rivets, or the resiliently urged jaws of
the clamps themselves Thus the guiding bar may be designed as a
springy hollow bar the entrance ends of which are flared to facilitate
the insertion of the plate In order to hold together such portions of
the plates which are at the edge opposite the frame, pressure members
may be provided on the yoke member embracing the plate and may be
secured adjacent the arcuate portion of the yoke member and be
provided with springs or not and are acting to urge the sheets towards
one another.
The simple microscope of the device may comprise, depending upon the
magnification desired, ordinary lenses, aplanatic lenses or wide angle
lenses For a higher magnification compound microscopes can be used The
arrangement may be made such that simple and compound microscopes of
different magnifying powers are easily interchangeable Thus a runner
having an internally cylindrical or conical bore may be provided to
enable the simple or compound microscopes to be easily insertable or
removed The runner may be connected with the U-shaped member by means
of eyes.
Since a simple or compound microscope has 70 a comparatively small
visual field it may be desirable to find out, prior to reading, the
approximate reading place on the plate carrying the micro-reproduction
For this purpose a place-finding lens of low magnifying power 75 may
be utilised which can be slipped on the tube of the simple or compound
microscope with which the reading device is used by means of a
suitable spring clamp To find out the desired reading field quickly
the place-finding 80 lens may be turned around the shaft Another
possibility of attaching the place-finding lens consists in attaching
it by means of a spring yoke to the U-shaped yoke member serving as a
sliding track in such a manner as to be 85 slidable thereon.
The micro-reproduction at the two faces of the plate are separated
from each other by an intermediate space This intermediate space is
occupied by the material of the plate which may 90 either be opaque if
it consists of metal or other opaque material The plate may be,
however, also translucent so as to constitute between the
micro-reproductions on both faces a translucent intermediate layer The
characters being 95 represented in micro-reproduction on both faces of
the plate thus have a certain distance from each other which, however,
in most cases will not be very important If the microgram plate is
very thin and clearly transparent it 100 might happen that,
notwithstanding an accurate focusing adjustment of the microscope,

reading is impaired by the microgram on the opposite face This is the
reason why a thin microgram plate should either be opaque so that a
micro 105 gram is observed by reflected light or it should be
translucent but not transparent so that the microgram applied on the
other face does not impair reading.
It is still possible to use a clearly transparent 110 microgram plate
if it is of such thickness that upon observation of the one face of
the plate by the microscope the opposite face carrying another
micro-reproduction appears blurred or out of focus 115 These and other
features of the invention will appear more fully from the following
detailed description of several embodiments thereof in connection with
the accompanying drawings given merely by way of example and 120 in
which:
Fig 1 is a plan view of the first embodiment of a device according to
the invention in which a circular plate is used; Fig 2 is a sectional
elevational view of the 125 device showing the yoke member; Fig 3 is
part of a sectional view taken on the line A-B of Fig 2; Fig 4 is a
plan view of another embodiment of the invention showing with full
lines a 130 785,843 diameter of about four inches 16000 catchwords of
a pocket dictionary if the height of letters is approximately 6 3,u,
while on the reverse side of the plate a further 16000 words may be
placed The material carrying the micro 70 reproduction may also be
provided on a foil or on a film which is placed between two
transparent sheets to form a plate.
A pivot pin 2 extends through the centre of plate 1 about whichpivot
theplate may be rotat 75 ed Pin 2 has pivoted thereto a yoke member 3
providing a guiding member for a microscope.
The U-shaped yoke member 3 overlies with its legs both faces of the
plate 1 A runner 4 carrying a simple microscope 5 is slidably 80
attached to the yoke member 3 so as to be movable from the axis of the
plate 1 up to its edge and back again in a similar manner as the
cursor of a slide rule For this purpose both sides of the yoke member
3 are provided each 85 with a guiding slot or guiding groove 6 within
which a guiding pin 7 of the runner 4 is slidably engaged The
connection between runner 4 and yoke member 3 is such as not to hinder
the sliding motion of the runner when changing 90 from one side to the
other over the edge 8 of the plate.
In order to prevent the runner from being lifted at one side by being
tilted when moved which would impair the reading by means of 95 the
microscope, the runner is provided at its ends with a small U-shaped
extension 9 at each end in slidable engagement with a flange 10 of the
yoke member 3 whereby the runner 4 is safely held on its guiding
member The flanges 100 only extend over the straight part of the yoke
member and are not provided on the curved part.

To facilitate handling of the device the edge 8 of the plate 1 is
knurled 105 To prevent the micro-reproduction on the plate 1 from
being marred it is either provided with a resistant coat of lacquer or
covered by two plexiglass (Registered Trade Mark) sheets 11 110 In a
modification of the construction shown the reading device may also be
provided on the pivot pin 2 with a winding-up spring and a braking
mechanism (not shown) so that during the use of the device the plate 1
is rotated In 115 this case a control button should be provided on the
yoke member 3 to permit stopping the rotation of the plate in any
desired location.
Figs 4 to 6 show another embodiment of the invention with which a
compound microscope 120 is used Both a circular plate 1 and a
rectangular plate 12 can be used as shown The circular plate 1 carries
a pivot pin 2 on which, as in the embodiment shown in Figs 1 to 3, a
yoke member 3 serving as a guiding member is 125 mounted so as to
extend over both faces of the plate The yoke member 3 has slidably
attached thereto by means of eyes 13 a runner 14 having an internally
cylindrical or conical socket into which the tube 15 of the microscope
130 circular plate and with dotted lines a rectangular plate and the
arrangement for attaching a compound microscope, this latter being
illustrated in its position when changing from one face of the plate
to the other; Fig 5 is a side view of the device shown in Fig 4; Fig 6
is a plan view similar to Fig 4 with the microscope being directed
towards one face of the plate; Fig 7 is a plan view of a rectangular
plate provided with a U-shaped frame encompassing the plate on three
edges and showing a microgram of a map; Fig 8 is a sectional view
taken on the line A-B of Fig 7; Fig 9 is a plan view of a plate
showing two frame members attached to opposite sides of the plate; Fig
10 shows in diagrammatic manner a place-finding lens attached to the
tube of the microscope; Fig 11 shows the manner in which the
placefinding lens may be shiftably attached to the U-shaped yoke
member; Fig 12 shows a springy lateral frame member used for holding
the plates together and Fig 13 another embodiment of the arrangement
shown in Fig 12; Fig 14 shows a magnetic connection between the runner
and U-shaped member and Fig 15 another magnetic connection between
runner and U-shaped member in section through a pair of intermediate
members, the plane of section being normal to the sliding track; Fig
16 shows an embodiment employing holding strings instead of a rigid
U-shaped member in their position of rest and Fig 17 a similar view,
however with the strings being extended for reading at a place on the
plate which cannot otherwise be reached; Fig 18 shows a slider
attached to the edge of a plate and provided with notches for guiding
the resilient strings; Fig 19 shows a corresponding slider, with holes
instead of notches; Fig 20 shows in which way the U-shaped slider

embraces the edge of the plate; Fig 21 shows an arrangement of the
resilient strings; Fig 22 shows a runner cooperating with resilient
strings and provided with eyes and Fig 23 a runner provided with holes
through which the resilient strings are passed; Fig 24 shows the
arrangement of a condenser to improve the illumination of the
microreproduction to be read off.
The first embodiment of our present device comprises a circular plate
1 on both faces of which the complete contents of a dictionary, time
table, or other records are attached, printed or applied in a
photomechanical manner In this way it is possible, for instance, to
accommodate on one face of a plate having a 785,843 is insertable The
arrangement may be made such that microscopes of different types and
magnifying power or lenses can easily be interchanged If desired, the
yoke member can be made of a springy material so that the objective of
the microscope is urged vithl light pressure towards the text-bearing
plate in order to give the objective the necessary fixed location.
The adjustment of the text-bearing plate to the desired point of
observation is effected, in the case of the embodiment having a
circular plate 1 as previously described, by rotating the yoke member
about the pivot 2 With the embodiment having a rectangular plate 12
the yoke member is displaced parallel to one edge of the plate as
described hereinafter in detail by way of example.
In the embodiments of Figs 7 to 15 a microgram plate 16 is held
between two transparent rectangular sheets 11 of glass or plastic The
microgram plate has applied to its both faces e.g by sticking or
photographically the micrograms to be read As already noted the
microgram plate should either be opaque or translucent and
non-transparent or, if clearly transparent, it should be thick enough
that as regards the focal length of the lens or objective the
observation of the microgram on one face of the plate is not impaired
by the microgram on its other face.
The plate 12 is embraced at three edges by legs 17 and 18 of a frame
member not only Ushaped in cross section but also in its general
configuration 19 and 20 denote the parallel legs of the U-shaped frame
as such The likewise parallel legs 17 and 18 of the U cross section
are at a distance from each other to permit the insertion of the
sheets 11 holding the microgram plate 16 between them such that the
sheets 11 remain at the desired location without, however, rendering
the insertion of the plate into the frame difficult The legs 19 and 20
of the frame member may be made longer or shorter, as desired, or may
be so dimensioned that they extend throughout the entire length of the
edges On the other hand it is not necessary that the legs 17 and 18 of
the frame member cover the entire length of the edge It would be
sufficient if they have the same length as the legs 19 and 20 measured

from the two corners.
The U-shaped frame member completed by the legs 17 and 18 is connected
by means of a web 21 to a round bar 22 encircled by a slider 23 in
more than 180 The slider 23 is provided at both of its ends with slits
24 assuring a firm, though springy, guidance of the slider 23 on the
round bar 22 The slits 24 are indicated by fine lines obliquely
disposed in relation to the axis The slider 23 further has secured
thereto a U-shaped sliding track 25 designed in the manner previously
described in connection with Figs 2 and 3 The simple microscope 26 may
be directed in the manner likewise described in the foregoing to both
faces of the microgram plate 16 by sliding the microscope on the
U-shaped yoke member 25.
As the sheets 11 are not held by the frame member at their edges
opposite the frame 70 member they might have the tendency to separate
from each other To prevent this two pressure members 27 are provided
the distance between which is equal to the distance between the outer
faces of the sheets 11 The pressure 75 members 27 are secured to the
U-shaped sliding track adjacent its arcuate portion 28.
The inward projection of the pressure members 27 i e the distance
between them, may be rendered variable by known means e g if a 80 film
placed between the sheets 11 is to be moved for observation, because
in this case the pressure between the two sheets 11 must not be as
high as when observing an immovable microgram.
Alternatively a small recess 29 may be provided 85 in the microgram
plate which recess extends throughout the length of the plate and is
so dimensioned as to permit the film to be inserted and drawn through.
Since the visual field of a microscope having 90 an ordinary aplanatic
lens is comparatively small it may be replaced by one having a wide
angle lens provided with two eye pieces as in binoculars In case such
microscopes are not sufficient to permit rapidly finding the region 95
of the microgram to be observed, a placefinding lens 30 with low
magnifying power and a larger visual field may be employed which is
clamped by means of a correspondingly shaped spring 31 onto the tube
32 of the microscope 26 100 This permits the lens 30 to be rotated
about this tube whereby searching is greatly facilitated.
In a modification of the above the placefinding lens 30 may be
attached by means of an 105 intermediate web 33 to a spring yoke 34
slidably displaceable on the guiding member 25.
If the place-finding lens 30 is not necessary it may be removed from
the tube 32 or from the guiding member 25 in a simple manner 110 The
lenses may be provided with eyepiece cups and be made adjustable for
focusing.
The U-shaped frame member shown in Fig.
7 may be replaced by two clamp-type frame members 35 and 36 secured to

opposite edges 115 of the rectangular plate If necessary these frame
members may be fastened to the plate 12 by means of screws, clamps,
rivets or the like 37 A guiding bar 38 for the slider is provided on
one of the two frame members 120 Our novel device permits of quickly
and simply interchanging of micrograms of all kinds in the reading
device For exchanging one microgram for another first the slider 23,
together with the U-shaped sliding track 25 is 125 removed from the
guiding bar 22 Then the sheets 11 are withdrawn from the frame
together with the micrograms held between them whereupon the
micrograms are removed from between them and replaced by new ones 130
785,843 ponding ribs 46 of the guiding means 45.
Instead of using permanent magnetic material for the runner or for the
sliding track it is also possible, if the guiding means is
ferromagnetic, to provide on the runner non 70 ferromagnetic,
ferromagnetic or permanent magnetic intermediate members 48, e g in
recesses 49 of the runner These intermediate members 48 are guided in
grooves 50 of the guiding means 51 75 If the lens runner or the
sliding track is magnetisable and one of these two elements is a
permanent magnet, the intermediate members 48 need not be
ferromagnetic or permanent magnets This arrangement ensures not only
80 a safe adjustment of the microscope with respect to the microgram
but also proper lateral guidance of the runner 52 on the guiding means
without it being necessary to provide lateral projections or flanges
on the runner and 85 without the provision of lateral guiding rails on
the guiding means In view of the fact that the magnetic force is
acting only on small opposed surfaces it may be convenient even when
intermediate pieces are used to provide lateral 90 guiding flanges and
projections such as 46, and 47, as shown in Fig 14.
It is to be understood that though gaps are shown between the parts
44, 45 and also the parts 51, 52 these parts are actually in contact
95 the gaps being merely shown to indicate that they are relatively
displaceable.
A very simple and inexpensive holding device for the microscope is
illustrated in Figs 16 to 23 In this embodiment extensible resilient
100 holding strings 53 are substituted for the previously described
rigid U-shaped member.
These holding strings have attached thereto the lens for the simple
microscope 54 in such a manner that it can be laterally displaced To
105 this end the lens is inserted into a runner 55 which is provided
either with eyes or holes 56 through which the resilient strings
extend.
This arrangement permits the displacement of the microscope in the
direction of the 110 resilient strings from one edge of the plate 12
to its other edge.

For displacing the microscope transversely to the direction of the
strings 53 it will be sufficient to exert a lateral pressure on the
runner 55 for 115 displacing the microscope up to the desired point
Owing to the elasticity of the strings 53 the microscope may be
directed to any point of the reading field.
The strings may be arranged to extend over 120 the plate 12 either in
its longitudinal direction or in its transverse direction At the same
time the strings are urging the runner 55 towards the plate 12 so that
the microscope has always the same invariable working distance from
the 125 micro-reproduction.
The strings can be secured to the one edge of the plate by means of
knots or the like in holes, but as shown at the opposite edges of the
plate 12 they are guidedin a pair of notches 130 This having been done
the sheets are again inserted together with the micrograms into the
frame member and then the slider 23 is again slipped onto the guiding
bar 22 whereupon the device is again ready for reading.
The cross section of two clamp type frame members which have proved to
be particularly useful in practice are shown in Fig 12 and 13.
Fig 12 shows a frame member comprising two opposite springy legs 39
which can be formed simply by bending a metal strip The free ends of
the legs are bent so as to be flaring After the sheets 11 holding the
microgram plate between them are removed from this frame the two legs
39 more or less approach each other under the action of their own
elasticity The flaring configuration of the two free ends facilitates
the insertion of the plate The slider 23 is slidably mounted in the
manner described hereinbefore on the portion 40 of the frame in the
form of a guiding tube of approximately circular cross section.
While the embodiment shown in Fig 12 is characterised by an increased
stability it involves, however, a greater loss in the useful space of
the plate 12 which useful space is larger with the embodiment shown in
Fig 13.
In the latter case the free legs 41 of the frame are provided with a
throat 42 limiting the movement of insertion of the plate 12 The free
legs 41 also in this case are biased towards one another so that they
approach each other after removal of the plate 12 and firmly hold the
plate inserted between them.
The runner 43 (Fig 8) on the one hand must have sufficient clearance
for being easily movable on the sliding track 25 but on the other hand
it must have an invariable distance from the object after having been
focused on an object in order to permit the simple microscope 26 to be
exactly adjusted to the micro-reproduction These contradictory
requirements may be met with by a spring such as a leaf spring
provided within the runner Alternatively the small leaf springs may be
mounted as side extensions on the runner 43, to hold it in its

position of rest, said springs bearing frictionally on flanges
provided on the external sides of the two rails 25 of the yoke member.
Another possibility consists in providing a magnetic connection
between the runner and the guide means For this purpose either the
runner 44 or the guide means 45 or both may be made permanent magnets
If only one of these two elements is a permanent magnet the other must
be of a ferromagnetic material The runner may be displaced along the
guiding means without this movement being hindered by the magnetic
attraction and is held firmly and without clearance on the guiding
means which permits a very exact adjustment of the microscope with
respect to the microgram To prevent the runner from being lost or from
being laterally displaced, laterally embracing flanges 47 are provided
engaging with corres785,843 or recesses 59 in such a manner that they
will not be displaced laterally For bringing the microscope 54 to the
other face of the plate 12 it is only necessary to lift the strings 53
by means of the runner 55 out of their recesses 59 and to move the
runner 55 to the other face.
Instead of providing recesses 59 of invariable location, U-shaped
sliders 60 may be used 1 o which embrace the edge of the plate 12 and
are provided with grooves 61 or holes 62, in which or through which
the resilient strings 53 are guided This enables the strings 53 to be
displaced on one of two opposite edges of the plate 12 or on both
opposite edges in such a manner that since no elongation or only a
slight resilient elongation of the strings 53 is necessary for
locating the microscope 54 at any desired position, the microscope
does not have to be manually retained in position.
The elastic strings, bands, or cords may be of any suitable elastic
material such as rubber or plastic, or in the form of covered or
uncovered spiral springs or the like.
Also with this embodiment an intermediate plate 57 may be provided
between the two protecting covering sheets 11 consisting e g of
plexiglass (Registered Trade Mark) This intermediate plate may be as
mentioned hereinabove of an opaque or a translucent material or, if of
sufficient thickness, of transparent material.
On observation by means of a microscope in particular on observation
by means of a compound microscope, the light intensity of theobserved
space is reduced It is thus possible that, if the illumination of the
surrounding is poor, the micro-reproduction becomes illegible.
This can be avoided by using a condenser lens arranged opposite the
simple or compound microscope at the other face of the plate if the
plate is translucent or transparent, as shown in Fig 24 The embodiment
of Fig 24 shows a condenser lens 64 mounted in a tube or the like 65
secured to a connecting yoke 66 the other end of which can be clamped
in a similar way to the tube 32 of the microscope or to the tube 15 of

the compound microscope shown in Figs 4-6 The arcuate portion 67 of
the connecting yoke 66 has been placed far enough outwardly to permit
the condenser together with the microscope to be moved over the entire
surface of the microgram plate 16 This arrangement ensures that the
condenser is, in any position of rest, opposite the simple or compound
microscope and always lights up the corresponding visual field of the
microscope even when the condenser is directed towards a comparatively
poor source of light The connecting yoke may be given a slight elastic
bias so that the base of the condenser is always slightly urged
against the guiding member 25 in order to prevent undesired movement
of the condenser lens and accordingly variations of the illumination
of the visual field.
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