The document give a brief idea of geneva mechanism and how it operates. this document also gives procedure to make geneva mechanism, methodology, components, design and calculations

1. SIES GRADUATE SCHOOL OF TECHNOLOGY
A PROJECT REPORT ON
GCM ( GENEVA CONVEYOR MECHANISM)
SUBMITTED BY:
SHUBHAM PATIL - 113A6046
NIKHILESH MANE - 218A6067
PRATHAMESH MOHOL - 218A6068
UMESH POL - 218A6077
In the partial fulfillment of second year in Mechanical Engineering fourth semester mini project report 2018 –
2019
Head of department:
R.S. NEHTE
Guided by:
DR. PRADEEP PATIL.
1.

2. INDEX
SR NO. TOPIC. PAGE NO.
1. ABSTRACT 3.
2. LITERATURE SURVEY 4.
3. METHODOLOGY 5.
4. DESIGN AND CALCULATIONS 6.
5. COMPONENTS 7.
6. PROCEDURE 8.
7. RESULT 9.
8. CONCLUSION 10.
2.

3. ABSTRACT
The Geneva mechanism is a gear mechanism that translates a continuous rotation into an intermittent rotary
motion. The project comprises of geneva wheel having 4 drive slots.
The wheels driven by driver which has two concentric circular wheel of different radius one wheel is used
for driving the geneva wheel while the smaller is used for providing support to geneva wheel.
The rotating drive wheel has a pin that reaches into a slot of the driven wheel advancing it by one step. The
drive wheel also has a raised circular blocking disc that locks the driven wheel in position between steps.
The movement of driver is hand controlled as there is knob provided on back side of wheel.The are two
rollers used of which one is driven by geneva wheel and other roller is idle roller. The belt is connected
between two rollers.
As the driver is rotated the wheel also rotates which in turn rotates the roller and belt is displaced by certain
distance.
3.

4. INTRODUCTION AND LITERATURE SURVEY
Geneva mechanism, also called Geneva Stop, one of the most commonly used devices for producing
intermittent rotary motion, characterized by alternate periods of motion and rest with no reversal in direction.
The name, Geneva drive, is derived from the device's earliest application in mechanical watches, which
were popularized in Geneva, being the classical origin of watchmaking industry.
In the most common arrangement of the Geneva drive, the client wheel has four slots and thus advances
the drive by one step at a time (each step being 90 degrees) for each full rotation of the master wheel. If the
steered wheel has n slots, it advances by 360°/n per full rotation of the propeller wheel.
One application of the Geneva drive is in film movie projectors and movie cameras, where the film is
pulled through an exposure gate with periodic starts and stops. Other applications of the Geneva drive
include the pen change mechanism in plotters, automated sampling devices, banknote counting machines,
and many forms of indexable equipment used in manufacturing .
Application of geneva mechanism - film projectors
4.

5. METHODOLOGY / WORKING
As shown in the Figure the driver A carries a pin that fits in the four radial slots in the follower B. Between
the slots there are four concave surfaces that fit the surface S on the driver and serve to keep the follower
from rotating when they are fully engaged. In the position shown, the pin is entering one of the slots, and, on
further rotation of the driver, it will move into the slot and rotate the follower through 90°. After the pin
leaves the slot, the driver will rotate through 270° while the follower dwells—i.e., stands still. The lowest
practical number of slots in a Geneva mechanism is 3; more than 18 are seldom used.
The driven wheel (geneva) is connected to shaft of the roller. The two rollers are connected by a belt on
which loads or jobs are kept. As the C roller is rotated by geneva wheel the idle roller D is also rotated. The
rotation of the geneva wheel is done by hand as there is knob provided on the backside of the driving wheel.
5.

6. DESIGN AND CALCULATION
The dimensions of geneva wheel- The dimensions of driving wheel
base diameter d= 12cm smaller wheel r = 4cm
slot dimensions- l = 4.3cm, w = 1.5cm bigger wheel r = 6cm
The curve fillet radius r = 4cm the angular slot cut (smaller wheel) = 90 degree
CALCULATIONS -
To calculate the linear displacement of belt for one rotation of driving wheel
Rotating roller radius r = 0.025m
Angular displacement of roller θ = 1.57 radians
The linear displacement of belt l = r.θ
= 0.025 * 1.57
= 0.03925m = 3.925cm.
Therefore the distance between two rollers stand is L= 38cm
Therefore the driving has to be rotated n= L/l = 9 times.
6.

7. COMPONENTS
1) Wood blanks for making for making the geneva wheel and driver wheel along with stand.
2) Plastic rollers.
3) Belt.
4) Pen as shaft.
5) Screws,nuts, bolts.
7.

8. PROCEDURE
First we designed the geneva wheel and driving wheel as shown below:-
Then we cut the geneva wheel and driving wheel from wooden blank.
Then we stand for rollers and fitted the rollers into the stands according to the marking.
Then we assembled all the parts and finally completed the project.
8.

9. RESULT
The project was successfully completed within the due date. The project has 9 links.
There is 3 degrees freedom.
The problems occured while balancing the driving wheel. It was solved by tightening it with stand
with nuts.
The another problem occured due to slip between roller and belt. It was solved providing friction
between roller and belt. The driving wheel is to be rotated 9 times to move a job from roller 1 to roller 2.
9.

10. CONCLUSION
This is the report of our second year mini project (KOM) which comprises of every detail right
from process sheet to design to calculations etc. Thus the project of Hydraulic project was successfully
completed by us.
The project was completed within the due date. The project was made as per design given in synopsis
and perfectly resembles it.
We thank all those who helped us in making this project a success.
10.