The document describes the design and analysis of a car jack using CAD software CATIA and FEA software ANSYS. It was a summer training project completed by two students to fulfill their degree requirements. The project involved modeling a scissor jack in CATIA, analyzing it using ANSYS to determine stresses and efficiency, and optimizing the design to improve the jack's life and performance. The document provides background on different types of jacks, prior research, and specifications and working of scissor jacks to support the project objectives.

1. 1
DESIGNING & ANALYSIS OF A CAR JACK
USING CATIA & ANSYS
A SUMMER TRAINING PROJECT REPORT
Submitted by
DIVAY CHADHA-21213303612
SACHIN KUMAR-19313303612
In partial fulfillment for the award of the degree
of
BACHELOR OF ENGINEERING
in
MECHANICAL & AUTOMATION ENGINEERING
HMR INSTITUTE OF TECHNOLOGY & MANAGEMENT, HAMIDPUR
IP UNIVERSITY: DWARKA 110078
NOVEMBER 2014

2. 2
BONAFIDE CERTIFICATE
Certified that this project report “DESIGNING & ANALYSIS OF A CAR
JACK USING CATIA & ANSYS” is the bonafide work of “DIVAY CHADHA
(21213303612); SACHIN KUMAR (19313303612)” who carried out the project
work under my supervision.
SIGNATURE SIGNATURE
Prof. S.K. GUPTA EHSAAN ASGAR
HEAD OF THE DEPARTMENT ASSITANT PROFESSOR
Mechanical Engineering Mechanical Engineering
HMRITM HMRITM
Submitted for viva-voice examination of IP UNIVERSITY, DWARKA
held at HMR INSTITUTE OF TECHNOLOGY & MANAGEMENT,
HAMIDPUR on __14 NOVEMBER 2014__
INTERNAL EXAMINER EXTERNAL EXAMINER

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ACKNOWLEDGEMENT
We are submitting our gratitude to our Director
Dr.S.S. INAMDAR for his care and concern for our welfare throughout our
learning carrier.
We whole heartedly thank our beloved Chairman SH.
ANIL KUMAR GUPTA, for his constant encouragement shown to us during our
course of study.
We express our sincere thanks to our Head of Mechanical & Automation
Engineering Department Prof. S.K. GUPTA, for his most valuable guidance,
advice and encouragement in all stages of our project work.
We express our deepest gratitude to our project guide
EHSAN ASGAR, Assistant Professor, Dept. of Mechanical Engineering and S.N.
SHARMA, Trainer (HCL) For their continuous guidance and suggestions.
We thank one and all who directly and indirectly helped us to bring this
project successful one. We extend our thanks to our mechanical department staff
members and to our family whose timely help enabled us to complete our project
in time.

4. 4
ABSTRACT
A Screw jack is a portable device consisting of a screw mechanism used to raise or
lower the load.
There are two types of jacks-mechanical and hydraulic
Mechanical jacks can be either hand operated or power driven.
The hydraulic jack consist of cylinder and piston mechanism
Although a jack is a simple device used to raise various types of loads
Proper size, strength and stability are essential requirements for the design of the
screw jack from safety consideration.

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CONTENTS
1 INTRODUCTION TO JACKS
2 LITERATURE SURVEY
2.1 EARLIEST JACK DEVELOPMENT
2.1.1 HIS WORK
2.1.2 FURTHER IMPROVEMENTS
3 PROBLEM DEFINITION
4 OBJECTIVE
5 SCISSOR JACK
6 MARKET RESEARCH
7 3-D MODELS (CATIA V5R20)
8 ANALYSIS (ANSYS)
9 CONCLUSION
10 REFERENCES

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CHAPTER 1
INTRODUCTION
1.1 GENERAL INTRODUCTION
Our survey in the regard in several users of vehicles, revealed the facts that mostly some difficult
methods were adopted in lifting the vehicles for reconditioning. Now the project is mainly
concentrated on this difficulty, such that the vehicle can be lifted from the floor land without
application of any impact force. The motorized screw jack has been developed to cater to the
needs of small and medium automobile garages, which are normally man powered with
minimum skilled labor. In most of the garages the vehicles are lifted by using screw jack. This
needs high man power and skilled labour. In order to avoid all such disadvantages, the built-in
jack should be designed in such a way that it can be used to lift the vehicle very smoothly
without any impact force. The operation is made simple so that even unskilled labour can use it
with ease. As automobile market is growing, advance concepts are being implemented to make
automobiles more and more versatile and comfortable. Many concepts are implemented day to
day to make automobile better and better these days. One such concept is of variable height
adjustment in vehicle by adjusting its ground clearance. In this way the vehicle becomes more
versatile and can be operated over variety of bad as well as good road conditions.
1.2 CURRENT SCENARIO:
WHAT IS A JACK?
A mechanical jack is a device which lifts heavy equipment and vehicles so that maintenance can
be carried out underneath. Car jacks usually use mechanical advantage to allow a human to lift a
vehicle by manual force alone. More powerful jacks use hydraulic power to provide more lift
over greater distances. Mechanical jacks are usually rated for maximum lifting capacity.
 Automotive jacks are classified as:

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1. Hydraulic jacks:
A. Bottle shape :
B. Floor jack :

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2. Screw Type
A. Scissor jack :
B. Bumper jack :

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1.3 CURRENT MECHANISM OF JACK OPERATION
Hydraulic jacks:
 Hydraulic jacks are typically used for shop work, rather than as an emergency jack to
be carried with the vehicle.
 In these jacks, by operating the handle, which is a lever (a simple machine), fluid is
compressed and routed to an actuating cylinder. This results in lift.
 Hydraulic jacks are often used to lift elevators in low and medium rise buildings.
WORKING:
A hydraulic jack uses a fluid, which is incompressible, that is forced into a cylinder by a
pump plunger. Oil is used since it is self-lubricating and stable. When the plunger pulls
back, it draws oil out of the reservoir through a suction check valve into the pump
chamber. When the plunger moves forward, it pushes the oil through a discharge check
valve into the cylinder. The suction valve ball is within the chamber and opens with each
draw of the plunger. The discharge valve ball is outside the chamber and opens when the
oil is pushed into the cylinder. At this point the suction ball within the chamber is forced
shut and oil pressure builds in the cylinder.
TYPES OF HYDRAULIC JACKS
1. Floor Jacks: These jacks are primarily used to lift heavy equipment from the surface
of the floor. It is more often used to change the tyres of vehicles.
2. Hydraulic Bottle Jacks: Hydraulic bottle are versatile since they can be placed in
tight spots and provides good leverage. They have a longer handle as compared to rest of
the hydraulic jacks and push up against a lever that gives a lift to the main lift arm. With
their use, it is possible to give a greater lift per stroke.

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3. Long Ram Jacks: In simple terms, it is a hydraulic jack with a long size ram. Its lever
handle is quite easy to use. It is primarily used for performing various types of repairing
work.
4. Shop Press jacks: They are of great use in press jobs where there arises a need to
generate tremendous pressure with minimum effort.
SCREW JACKS:
A jackscrew is a type of jack which is operated by turning a leadscrew. In the form of
a screw jack it is commonly used to lift heavy weights such as the foundations of houses, or
large vehicles.
 In the case of a screw jack, a small force applied in the horizontal plane is used to raise or
lower large load.
 A jackscrew's compressive force is obtained through the tension force applied by its lead
screw.
 Harsh environment applications such as steel mills, mining, oil & gas, and primary metal
smelting operations, here screw Jacks are preferred over hydraulics. In these
environments where hydraulic cylinders would simply not survive the fluctuating
temperatures.
 A jackscrew's threads must support heavy loads. In the most heavy-duty applications,
such as screw jacks, a square thread or buttress thread is used, because it has the
lowest friction. In other application such as actuators, an Acme thread is used, although it
has higher friction.

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TYPES OF SCREW JACKS
1. Scissor jack: A scissor jack is a device constructed with a cross-hatch mechanism, much
like a scissor, to lift up a vehicle for repair or storage. It typically works in just a vertical
manner. The jack opens and folds closed, applying pressure to the bottom supports along
the crossed pattern to move the lift. When closed, they have a diamond shape. Scissor
jacks are simple mechanisms used to drive large loads short distances. The power screw
design of a common scissor jack reduces the amount of force required by the user to drive
the mechanism. Most scissor jacks are similar in design, consisting of four main members
driven by a power screw. A scissor jack is operated simply by turning a small crank that
is inserted into one end of the scissor jack. This crank is usually "Z" shaped. The end fits
into a ring hole mounted on the end of the screw, which is the object of force on the
scissor jack. When this crank is turned, the screw turns, and this raises the jack. The
screw acts like a gear mechanism. It has teeth (the screw thread), which turn and move
the two arms, producing work. Just by turning this screw thread, the scissor jack can lift a
vehicle that is several thousand pounds.
2. Bumper jacks: They were used earlier and are not prevalent nowadays.

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1.4 PROS AND CONS OF BOTH MECHANISMS
Screw Jacks and Hydraulic Cylinders each offer their own unique advantages as lifting and
positioning devices
SCREW JACKS:
 Over time, hydraulic cylinders can lose position or “creep” due to loss of pressure at the
pump or through the cylinder seal. In some cases, a damaged hydraulic line or hose can
cause complete loss of position. This will not happen with Screw Jacks since the primary
lifting mechanism (acme thread) is inherently self-locking i.e. the jack will not “creep”
even when the drive motor is shut down.
 Screw jacks are often preferred for their self-locking characteristics, ability to withstand
harsh environments, minimal drive components, and high duty cycles.
 Scissor jacks are handy because they are compact when they are in their contracted
position.
 Harsh environment applications such as steel mills, paper mills, mining, oil & gas, and
primary metal smelting operations are the areas where Screw Jacks are preferred over
hydraulics. Jacks commonly operate for many years in these environments where
hydraulic cylinders would simply not survive the fluctuating temperatures and gritty
conditions without frequent breakdown.
 Additional benefits of screw jacks include minimal drive components and setup
simplicity. Where hydraulics require a pumping device, oil reservoir, and oil lines, Joyce
Screw Jacks can be directly connected to a drive motor and a simple on/off control
device.
HYDRAULIC JACK:
 These jacks are sturdier than the scissor jacks and can lift heavier loads.

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CHAPTER 2
LITERATURE SURVEY
2.1 PAST WORK DONE
EARLIEST JACK DEVELOPMENT:
 There is evidence of the use of screws in the Ancient Roman world but it was Leonardo
da Vinci, in the late 1400s, who first demonstrated the use of a screw jack for lifting
loads.
HIS DESIGN:
 Leonardo design used a threaded worm gear, supported on bearings, that is rotated by the
turning of a worm shaft to drive a lifting screw to move the load - instantly recognizable
as the principle we use today.
FURTHER IMPROVEMENTS:
Screw type mechanical jacks were very common for jeeps and trucks of World War II
vintage. For example, the World War II jeeps were issued the "Jack, Automobile, Screw
type, Capacity 1 and 1/2 ton".
With the industrial revolution of the late 18th and 19th centuries came the first use of
screws in machine tools, via English inventors such as John Wilkinson and Henry
Maudsley. During the early 1880s in Coaticook, a small town near Quebec, a 24-year- old
inventor named Frank Henry Sleeper designed a lifting jack. Like da Vinci’s jack, it was a
technological innovation because it was based on the principle of the ball bearing for
supporting a load and transferred rotary motion, through gearing and a screw, into linear
motion for moving the load. The device was efficient, reliable and easy to operate. It was
used in the construction of bridges, but mostly by the railroad industry, where it was able
to lift locomotives and railway cars. The idea was based on the familiar lever and fulcrum
principle and he needed someone to manufacture it

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 There was clearly potential for using this technology for other applications and only 10
years later, in 1940, the first worm gear screw jack, that is instantly recognizable today,
was offered by Duff-Norton, for adjusting the heights of truck loading platforms and mill
tables.
Since then the product has evolved to push, pull, lift, lower and position loads of anything
from a few kilos to hundreds of tonnes. One of the biggest single screw jacks made to date is a
special Power Jacks E-Series unit that is rated for 350 tonnes even in earthquake conditions for
the nuclear industry.

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CHAPTER 3
PROBLEM DEFINITION
 The most common problem encountered while using scissor jack is the instability of jack
while giving jerks to loosen the wheel nut. Also the common jack having small base is
unable to provide proper support on uneven surface esp. off-road and no inclination in
that jack is tolerable.

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CHAPTER 4
OBJECTIVE
 The project relates to the designing of simple scissor jack and its analysis along with
structural improvements to make such a modified jack that is very stable and can take
enough load on uneven surfaces and somewhat inclination is also allowed.
 The project also aims at designing and finding stresses, efficiency, expected life of screw.
We endeavor to develop a scissor jack such that it is cost effective, having a long life and
can be handled roughly.

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CHAPTER 5
SCISSOR JACK
5.1 Specifications
 The term "scissor jack" describes a wide variety of tools that all follow the same
principle: using crossed beams to lift something. They do this by acting on the object
they are lifting in a diagonal manner; the lift on the right side lifts the object from its left
side and vice versa. This allows the user to store the jack when it is not in use (with the
diagonal beams flat) and to expand it when it is needed.
Fig. 5.1 Fig. 5.2
 The major specification of scissor lifts is that they are all symmetrical. In order to work,
the distance from the loaded point to the cross point must be the same as the distance
from the cross point to the ground. This ensures that weight is distributed equally
throughout the scissor lift beams.
 Since scissor lifts have such a wide variety of use, they also have a wide variety of power
sources. Scissor lifts for lifting cars can be powered electrically, hydraulically and of
course mechanically. On the other end of the spectrum, industrial scissor lifts that
people stand on are often powered by diesel, although electrical options do exist.

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 Scissor lifts basically fall into two categories: single scissor lifts and multiple scissor lifts.
A single scissor lift has just two crossbeams and one "x." This means it can only go so
high because the length of the crossbeams restricts the height of the lift, and making
them too long would make it unstable.
On the other hand, multiple lifts have beams crossing each other, and then attaching to more
beams that go the opposite direction. This allows the scissor lift to rise higher.
5.2 Assembly
A scissor jack has four main pieces of metal and two base ends. The four metal pieces are
all connected at the corners with a bolt that allows the corners to swivel. A screw thread runs
across this assembly and through the corners. As the screw thread is turned, the jack arms travel
across it and collapse or come together, forming a straight line when closed. Then, moving back
the other way, they raise and come together. When opened, the four metal arms contract
together, coming together at the middle, raising the jack. When closed, the arms spread back
apart and the jack closes or flattens out again.
5.3Working
A scissor jack uses a simple theory of gears to get its power. As the screw section is
turned, two ends of the jack move closer together. Because the gears of the screw are pushing up
the arms, the amount of force being applied is multiplied. It takes a very small amount of force to
turn the crank handle, yet that action causes the brace arms to slide across and together.
As this happens the arms extend upward. The car's gravitational weight is not enough to
prevent the jack from opening or to stop the screw from turning, since it is not applying force
directly to it. If you were to put pressure directly on the crank, or lean your weight against the
crank, the person would not be able to turn it, even though your weight is a small percentage of
cars.

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5.4 Components
 Frame
 Power screw
 Rivets
 Coupling nut
 Crank
5.4.1 Frame:
The entire frame of the scissor jack consists of links (top and bottom), base frame and
support frame. The frame is manufactured by sheet metal processes and forming by low-medium
carbon steel.
5.4.2 Power screw:
Power screws are used to convert rotary motion in to translational motion. It is also called
translational screw. They find use in machines such as universal tensile testing machines,
machine tools, automotive jacks, vises; aircraft flap extenders, trench braces, linear actuators,
adjustable floor posts, micrometers, and C-clamps. A screw thread is formed by cutting a
continuous helical groove around the cylinder. These grooves are cut either left hand or right
hand.
The majority of screws are tightened by clockwise rotation, which is termed a right-hand
thread. Screws with left-hand threads are used in exceptional cases. For example, anticlockwise
forces are applied to the screw (which would work to undo a right-hand thread), a left-hand-
threaded screw would be an appropriate choice.
Power screws are typically made from carbon steel, alloy steel, or stainless steel and they
are usually used with bronze, plastic, or steel mating nuts. Bronze and plastic nuts are popular for

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higher duty applications and they provide low coefficients of friction for minimizing drive
torques.
There are important terms and figures that need to be understood before designing power screws:
1. Pitch: is the distance from a point on one thread to the corresponding thread on the next
adjacent thread, measured parallel to the axial plane.
2. Lead: is the distance the screw would advance relative to the nut in one rotation. For single
thread screw, lead is equal to pitch.
3. Helix Angle: is related to the lead and the mean radius by the equation below;
Fig. 5.3
5.4.2.1 Basics of power screws
Power screws provide a compact means for transmitting motion and power. They are
ideal for replacing hydraulic and pneumatic drive systems as they require no compressors,
pumps, piping, filters, tanks, valves or any other support items required by these systems. Also,
screws don't leak so there are no problems with seals which are so common to hydraulic and
pneumatic systems. And, screw systems are quiet running - no noisy compressors, pumps or
exhaust valves. Screw systems are simple, reliable and easy to utilize.

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5.4.2.2 Power screw motions
There are four distinct motion converting actions that can be produced by power screws
and nuts. The two most common involve torque conversion to thrust. In Figure 1, the screw is
rotated (torqued) and the nut moves linearly producing thrust or the nut is rotated (torqued) and
the screw moves linearly. The two less common motions involve thrust conversion to torque. In
Figure 2, the nut undergoes a linear force (thrust) and the screw rotates or the screw undergoes a
linear force (thrust) and the nut rotates. These two motions are commonly referred to as "back
driving", "overhauling", or, improperly, "reversing".
Fig. 5.4 Fig. 5.5
5.4.2.3 Types of power screws
There are 3 types of screw threads used in power screws
1. Square threads:
 Is used for power transmission in either direction
 Results in maximum efficiency and minimum
 It is employed in screw jacks and clamps
2. Acme threads:
 It is a modification of square thread
 Efficiency is lower than square threads
 The slope increases the area for shear

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 It is easily manufactured
3. Buttress Thread:
 It is used when large forces act along the screw axis in one direction only.
 It has higher efficiency like square threads and ease of cutting like acme threads.
 It is the strongest thread of all
 It has limited use of power transmission
5.4.3 Rivets:
A rivet is a permanent mechanical fastener. Before being installed a rivet consists of a
smooth cylindrical shaft with a head on one end. The end opposite the head is called the buck-
tail. On installation the rivet is placed in a punched or pre-drilled hole, and the tail is upset, or
bucked (i.e. deformed), so that it expands to about 1.5 times the original shaft diameter, holding
the rivet in place. To distinguish between the two ends of the rivet, the original head is called the
factory head and the deformed end is called the shop head or buck-tail.
5.4.4 Coupling nut:
A coupling nut is a threaded fastener for joining two male threads, most commonly
threaded rod. The outside of the fastener is usually a hex so a wrench can hold it. Variations
include reducing coupling nuts, for joining two different size threads; sight hole coupling nuts,
which have a sight hole for observing the amount of engagement; and coupling nuts with left-
handed threads.
5.4.5 Crank
A crank is an arm keyed at right angles to the end of a shaft, by which motion is imparted
to the power screw .It mainly suffers from torsional stresses so medium carbon steel is used as it
combines merits of malleability and sufficient torsional strength.

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CHAPTER 6
MARKET RESEARCH
6.1 Product Comparison
Below are analyses two other car jacks that are similar to the jack I wish to design. They
represent the two primary models of scissor jacks available; those powered by electricity and
those that require manual input.
Picture Features Pros Cons
Fig 6.1
 Can lift up
to 990kg
 Electric
motor
powered
by a 12V
DC power
source.
 Extends
13”,
compacts
to less than
5”.
 7’ power
cord.
 Weighs
9kgs.
 The electric
motor
makes
operating
the jack
simple and
easy.
 Can
operate
jack away
from the
car.
 The added weight
of the electric
motor hurts fuel
economy.
 The motor adds
cost and the
increased
complexity of the
system creates
more opportunity
for failure.
 Need of an
electrical power
source could be a
hindrance when
battery power is
not adequate.

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Fig. 6.2
 Lifts 1133
kg.
 Extends
from 3.75”-
15.4”.
 Mechanical
input
required.
 The jack’s
simple
design
minimizes
cost , size
and weight,
so it can be
stored
easily.
 Does not
rely on
electricity.
 Operating the
crank can be
difficult.
 Required to be
near (practically
underneath a
2,000kg object to
operate.
 Like the product
above, there is no
stability provided
from the sides.
 Tools to raise the
jack are not
interchangeable.
It can be seen that the overall concept of the scissor jack is constant and that any new
product will be based on that concept.

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CHAPTER 7
3-D MODELS (CATIA V5R20)
7.1 Parts
Fig 7.1
Fig 7.2

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Fig 7.3
Fig 7.4

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Fig 7.5
Fig 7.6

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7.2 Assembly
Fig 7.7

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CHAPTER 8
ANALYSIS (ANSYS)
Fig 8.1
STRESS ON JACK BASE

30. 30
CHAPTER 9
CONCLUSION
Scissor Jacks are the ideal product to push, pull, lift, lower and position
loads of anything from a hundred of kilograms to a couple of tonnes. The need has
long existed for an improved portable jack for automotive vehicles. It is highly
desirable that a jack become available that can be operated alternatively from
inside the vehicle or from a location of safety off the road on which the vehicle is
located. Such a jack should desirably be light enough and be compact enough so
that it can be stored in an automobile trunk, can be lifted up and carried by most
adults to its position of use, and yet be capable of lifting a wheel of a 4,000-5,000
pounds vehicle off the ground. Further, it should be stable and easily controllable
so that jacking can be done from a position of safety. It should be easily movable
either to a position underneath the axle of the vehicle or some other reinforced
support surface designed to be engaged by a jack.
Thus, the product has been developed considering all the above requirements. This
particular design of the scissor jack will prove to be beneficial in lifting and
lowering of loads.

31. 31
CHAPTER 10
REFERENCES
10.1 Books referred
 Materials and heat treatment by O.P. khanna
 Design of machine elements by khurmi
 Strength of materials by R.K. rajput
 A textbook of machine design by P.C.Sharma and D.K.Agarwal, S.K.Kataria and sons,
2006.
 A text book of machine drawing by R.S Khurmi, S. Chand and Co. Ltd., 2005.
 Mechanical engineering design by Joseph E. Shigley, McGraw Hill, 1986.
10.2 Websites referred
 youtube.com(Davison Design: Jack 'N Stand Animated Video)
 google.com
 scribd.com
 Wikipedia.com
 Howstuffworks.com
 Sciencedirect.com
 B2bhydrualicjacks.com