Hydraulic Jacking System For 4 Wheelers

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1 Chapter-1 INTRODUCTION Screw type mechanical jacks were very common for jeeps and trucks of World War II vintage. For example, the World War II jeeps (Willys MB and Ford GPW) were issued the "Jack, Automobile, Screw type, Capacity 1 1/2 ton", Ordnance part number 41-J-66. This jacks, and similar jacks for trucks, were activated by using the lug wrench as a handle for the jack's ratchet action to of the jack. The 41-J-66 jack was carried in the jeep's tool compartment. Screw type jack's continued in use for small capacity requirements due to low cost of production raise or lower it. A control tab is marked up/down and its position determines the direction of movement and almost no maintenance. The screw has a thread designed to withstand an enormous amount of pressure. This is due to the fact that it is generally holding up heavy objects for an extended amount of time. Once up, they normally self-lock so that they won't fall if the operator lets go, and they hold up well to the wear of repeated use. If they are made with a ball nut, they will last longer because there is less friction created with this type of jack. However, they will not self-lock. This can be dangerous and handled carefully. Jacks are used frequently in raising cars so that a tire can be changed. A screw jack is commonly used with cars but is also used in many other ways, including industrial machinery and even airplanes. They can be short, tall, fat, or thin depending on the amount of pressure they will be under and the space that they need to fit into. 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.

Transcript of Hydraulic Jacking System For 4 Wheelers

Page 1: Hydraulic Jacking System For 4 Wheelers

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Chapter-1

INTRODUCTION

Screw type mechanical jacks were very common for jeeps and trucks of World War II

vintage. For example, the World War II jeeps (Willy’s MB and Ford GPW) were issued the

"Jack, Automobile, Screw type, Capacity 1 1/2 ton", Ordnance part number 41-J-66. This

jacks, and similar jacks for trucks, were activated by using the lug wrench as a handle for the

jack's ratchet action to of the jack. The 41-J-66 jack was carried in the jeep's tool

compartment. Screw type jack's continued in use for small capacity requirements due to low

cost of production raise or lower it. A control tab is marked up/down and its position

determines the direction of movement and almost no maintenance.

The screw has a thread designed to withstand an enormous amount of pressure. This is due to

the fact that it is generally holding up heavy objects for an extended amount of time. Once

up, they normally self-lock so that they won't fall if the operator lets go, and they hold up

well to the wear of repeated use. If they are made with a ball nut, they will last longer

because there is less friction created with this type of jack. However, they will not self-lock.

This can be dangerous and handled carefully.

Jacks are used frequently in raising cars so that a tire can be changed. A screw jack is

commonly used with cars but is also used in many other ways, including industrial

machinery and even airplanes. They can be short, tall, fat, or thin depending on the amount of

pressure they will be under and the space that they need to fit into.

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.

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Chapter-2

BRIEF SURVEY OF EXISTING LITERATURE

A jack is a mechanical device used as a lifting device to lift heavy loads or apply great

forces. Jacks employ a screw thread or hydraulic cylinder to apply very high linear forces.

A mechanical jack is a device which lifts heavy equipment. The most common form is a car

jack, floor jack or garage jack which lifts vehicles so that maintenance can be performed.

More powerful jacks use hydraulic power to provide more lift over greater distances.

Mechanical jacks are usually rated for a maximum lifting capacity (for example, 1.5 tons or 3

tons).

A screw jack is a portable device consisting of a screw mechanism used to raise or lower the

load. The principle on which the screw jack works is similar to that of an inclined plane.

There are mainly two types of jacks-hydraulic and mechanical. A hydraulic jack consists of a

cylinder and piston mechanism. The movement of the piston rod is used to raise or lower the

load. Mechanical jacks can be either hand operated or power driven.

Jacks are used frequently in raising cars so that a tire can be changed. A screw jack is

commonly used with cars but is also used in many other ways, including industrial

machinery and even airplanes. They can be short, tall, fat, or thin depending on the amount of

pressure they will be under and the space that they need to fit into.

The jack is made out of various types of metal, but the screw itself is generally made out of

lead. While screw jacks are designed purposely for raising and lowering loads, they are not

ideal for side loads, although some can withstand side loads depending on the diameter and

size of the lifting screw. Shock loads should also be avoided or minimized. Some screw jacks

are built with anti-backlash. The anti-backlash device moderates the axial backlash in the

lifting screw and nut assembly to a regulated minimum.

A large amount of heat is generated in the screw jack and long lifts can cause serious

overheating. To retain the efficiency of the screw jack, it must be used under ambient

temperatures, otherwise lubricants must be applied. There are oil lubricants intended to

enhance the equipment’s capabilities. Apart from proper maintenance, to optimize the

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capability and usefulness of a screw jack it is imperative to employ it according to its design

and manufacturer’s instruction. Ensure that you follow the speed, load capacity, temperature

recommendation and other relevant factors for application.

2.1 The Screw

The screw has a thread designed to withstand an enormous amount of pressure. This is due to

the fact that it is generally holding up heavy objects for an extended amount of time. Once

up, they normally self-lock so that they won't fall if the operator lets go, and they hold up

well to the wear of repeated use. If they are made with a ball nut, they will last longer

because there is less friction created with this type of jack. However, they will not self-lock.

This can be dangerous and handled carefully.

2.1.1 Operation:-

The jack can be raised and lowered with a metal bar that is inserted into the jack. The

operator turns the bar with his hands in a clockwise direction. This turns the screw inside the

jack and makes it go up. The screw lifts the small metal cylinder and platform that are above

it. As the jack goes up, whatever is placed above it will raise as well, once the jack makes

contact. The bar is turned until the jack is raised to the level needed. To lower the jack the

bar is turned in the opposite direction. An automatic screw jack has gears inside the jack that

are connected to the screw. Theses gears are connected by other gears and bars that are

turned by a power source to raise and lower the jack.

Although a jack is a simple and widely used device, the use of any lifting device is subject to

certain hazards. In screw-jack applications, the hazards are dropping, tipping or slipping of

machines or their parts during the operation. These hazards may result in serious accidents.

The main reasons of such accidents are as follows:

(i) The load is improperly secured on the jack

(ii) The screw-jack is over loaded.

(iii) The centre of gravity of the load is off centre with respect to the axis of the jack.

(iv) The screw-jack is not placed on hard and level surface.

(v) The screw-jack is used for a purpose, for which it is not designed.

Proper size, strength and stability are the essential requirements for the design of the screw-

jack from safety considerations.

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A mechanical jack is a device which lifts heavy equipment. The most common form is a car

jack, floor jack or garage jack which lifts vehicles so that maintenance can be performed. 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.

2.2 Scissor Jacks

Scissors jacks are also mechanical and have been in use at least since the 1930s.

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.

2.2.1 Construction:-

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

Fig 2.1: SCISSOR JACK [1]

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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.

2.2.2 Design and Lift:-

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 the cars.

Bottle screws may operate by either

(i)Rotating the screw when the nut is fixed; or

(ii)Rotating the nut and preventing rotation of the screw.

2.3 Hydraulic Jack

Hydraulic jacks are typically used for shop work, rather than as an emergency jack to be

carried with the vehicle. Use of jacks not designed for a specific vehicle requires more than

the usual care in selecting ground conditions, the jacking point on the vehicle, and to ensure

stability when the jack is extended. Hydraulic jacks are often used to lift elevators in low and

medium rise buildings.

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

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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.

2.3.1 Parts of Hydraulic Jack:-

Every hydraulic jack has six main components:

1. A Reservoir to hold hydraulic fluid.

2. A Pump that draws fluid from the reservoir on it's up, suction or intake stroke then createspressure on it's down/power stroke pushing the fluid through a delivery pipe.

3. Check Valve which after allowing fluid to pass from the reservoir to the pump now'checks' off the return port to the reservoir and directs the pressurized fluid to the cylinders.

4. Main Cylinder where the hydraulic fluid fills up and jack works.

5. Ram Piston is forced out or upwards as the main cylinder fills with pressurized fluid.

6. The Release Valve: After the jack has done its job and it is time to release the pressureallowing the ram piston to return back into the main cylinder is opened and the fluid is portedback into the reservoir so the jacking cycle can be repeated.

2.3.2 Types of Hydraulic Jacks

According to the situation and position required for lifting system two types of hydraulic

jacks are used for lifting automobile.

2.3.2.1 Air Hydraulic Jack

Basically jack climb up on the jack rod (part of the lifting trestle) with the desired pressure,

to lift up the load. Its action is same as a monkey that climbs a trunk tree; i.e., first it holds up

on the trunk with its legs and lunges upward, then it holds on the trunk with its hand and lifts

its leg up. At any time, either its hands or legs have a grip on trunk, which prevents it from

falling down.

In the same manner, air hydraulic jack, air hydraulic bottle jack and jack is provided with two

pairs of jaws, a lower pair of jaws and an upper pair of jaws for an excellent grip. During

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lifting, both the pairs “locked”. In this position

the jack can only move upwards. At this time

of lifting, the lower pair of jaws grips the trisle

rod while the jack lifts up.

After completing the full stroke, the upper pair

of jaws grips the trestle rod, however, the base

of the jack moves upward. During the process

of lowering, any one of the pairs is always

locked.

Lightweight and build for heavy-duty use. The quick-lift mechanism allows a substantially

shortened ram lifting time without load. Flow control valve prevents sudden falls of the ram.

Featured a specially processed air pump for low noise. The

built-in safety valve prevent use prevent use beyond rated

capacity or lifting limit.

2.3.2.2 Bottle Jack

In a bottle jack the piston is vertical and directly supports a

bearing pad that contacts the object being lifted. With a

single action piston the lift is somewhat less than twice the

collapsed height of the jack, making it suitable only for

vehicles with a relatively high clearance.

For lifting structures such as houses the hydraulic interconnection of multiple vertical jacks

through valves enables the even distribution of forces while enabling close control of the lift.

2.3.2.3 Floor Jack

In a floor jack a horizontal piston pushes on the

short end of a bell crank, with the long arm

providing the vertical motion to a lifting pad,

kept horizontal with a horizontal linkage.

Floor jacks usually include castors and wheels,

allowing compensation for the arc taken by the

Fig 2.2: AIR HYDRAULIC JACK [1]

Fig 2.3: BOTTLE JACK [1]

Fig 2.4: FLOOR JACK [1]

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lifting pad. This mechanism provides a low profile when collapsed, for easy maneuvering

underneath the vehicle, while allowing considerable extension.

2.3.2.4 Strand Jack

A strand jack (also known as strand jack) is a jack used to lift very heavy (e.g. thousands tons

or more with multiple jacks) loads for construction and engineering purposes.[1]Strand jacks

were invented in Europe in the 1970s in the development of post tensioning systems and are

now used all over the world to erect bridges, offshore structures, refineries, power stations,

major buildings and other structures where the use of conventional cranes is either

impractical or too expensive.

A strand jack is a hollow hydraulic cylinder with a set of steel cables (the "strands") passing

through the open centre, each one passing through two clamps - one mounted to either end of

the cylinder.

The jack operates in the manner of a caterpillar's walk: climbing (or descending) along the

strands by releasing the clamp at one end, expanding the cylinder, clamping there, releasing

the trailing end, contracting, and clamping the trailing end before starting over again. The

real significance of this device lies in the facility for precision control.

The expansion and contraction can be done at any speed, and paused at any location.

Although a jack may lift only 1700 tons or so, there exist computer control systems that can

operate 120 jacks simultaneously, offering fingertip feel movement control over extremely

massive objects.[1]

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Fig 2.5: STRAND JACK [1]

2.3.2.5 Pneumatic Jack

A pneumatic jack is a hydraulic jack that is actuated by compressed air - for example, air

from a compressor - instead of human work. This eliminates the need for the user to actuate

the hydraulic mechanism, saving effort and potentially increasing speed. Sometimes, such

jacks are also able to be operated by the normal hydraulic actuation method, thereby

retaining functionality, even if a source of compressed air is not available.

Fig 2.6: PNEUMATIC JACK [1]

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Chapter-3

NEED FOR NEW DEVELOPMENT

Our survey in the regard in several automobile garages, revealed the facts that mostly some

difficult methods were adopted in lifting the vehicles for reconditioning.

Now the project has mainly concentrated on this difficulty, and hence a suitable device has

been designed, such that the vehicle can be lifted from the floor land without application of

any impact force.

The fabrication part of it has been considered with almost case for its simplicity and

economy, such that this can be accommodated as one of the essential tools on automobile

garages.

The hydraulic 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 hydraulic jack. This needs high man power and

skilled labour.

In order to avoid all such disadvantages, the hydraulic jack has been 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.

The D.C motor is coupled with the Hydraulic jack by gear arrangement. The screw jack

shafts rotation depends upon the rotation of D.C motor. This is a simple type of automation

project.

This is an era of automation where it is broadly defined as replacement of manual effort by

mechanical power in all degrees of automation. The operation remains to be an essential part

of the system although with changing demands on physical input, the degree of

mechanization is increased.

Degrees of automation are of two types, viz.

Full automation.

Semi automation.

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In semi automation a combination of manual effort and mechanical power is required

whereas in full automation human participation is very negligible.

3.1 Need for Automation

Automation can be achieved through computers, hydraulics, pneumatics, robotics, etc.

Automation plays an important role in mass production.

For mass production of the product, the machining operations decide the sequence of

machining. The machines designed for producing a particular product are called transfer

machines. The components must be moved automatically from the bins to various machines

sequentially and the final component can be placed separately for packaging. Materials can

also

be repeatedly transferred from the moving conveyors to the work place and vice versa.

Nowadays, almost all the manufacturing processes are being atomized in order to deliver the

products at a faster rate.

The manufacturing operation is being atomized for the following

reasons:

To achieve mass production

To reduce man power

To increase the efficiency of the plant

To reduce the work load

To reduce the production cost

To reduce the production time

To reduce the material handling

To reduce the fatigue of workers

To achieve good product quality

Less Maintenance

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Chapter-4

PROPOSED METHODOLOGY

4.1 Limitations of floor jack:

Current floor jacks – Manually mounted on the vehicle frame, and necessitate an

external hydraulic pump or pneumatic system.

Permanently attached to the vehicle body - External and exposed to damage, they

can’t be conveniently operated.

4.2 Problem to be solved:

Make the hydraulic jack convenient and efficient to use from within the automobile.

4.3 Solution to be investigated:

Inventing an automatic built-in hydraulic jack to utilize automotive power steering fluid, and

testing the effects of hydraulic pressure on effectiveness of the invention.

4.4 Objectives

Provide a safe and simple automatic hydraulic jacking system without manual effort.

Provide an alternative jacking system that can operate without external sources of actuation,

such as extra hydraulic pumps, reservoirs, or pneumatic systems. This invention instead

utilizes the vehicle power steering system which is already in place.

Provide a novel jacking system that can be operated from within the vehicle by means of a

dashboard control panel.

Provide a novel hydraulic jacking system that is directly and permanently incorporated into

the vehicle frame in such a way as to prevent the additional risk of damage or weathering.

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Chapter-5

INNOVATION - OUR IDEA

“AUTOMATIC HYDRAULIC JACKING SYSTEM FOR

4 WHEELERS”

An automatic built-in hydraulic jack system that utilizes the power steering system of the

vehicle to operate a set of jacks directly incorporated into indentations in the vehicle frame.

When not in use, each jack will be fully retracted into the vehicle frame. Each jack consists

of a main jack cylinder, a slid able piston, and a jack stand and jack seal.

A pair of hydraulic lines runs from each jack to an automotive hydraulic control valve body,

which consists of a set of solenoid valves that regulate fluid flow from the power steering

pump and fluid reservoir to either the power steering rack and pinion during normal vehicle

usage or to each individual jack when the jacking system is engaged.

The jacking system can be controlled by means of a dashboard control panel consisting of a

set of switches regulating each solenoid valve within the control valve body.

5.1 Parts of Automatic Hydraulic Jacking

System

1. Hydraulic fluid Reservoir Tank:

It would be the tank for storing the hydraulic fluid and sending

it to the required hydraulic jack for lifting the vehicle through

respective hose pipes.

Fig 5.1: RESERVOIR TANK [2]

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2. Hydraulic Jacks:

Hydraulic jacks for lifting the vehicles, there will

be two numbers of hydraulic jacks that would be

installed in the vehicle on the chassis i.e., one on

the right side and one on the left side of vehicle.

3. Hydraulic pump:

Hydrostatic pumps are positive displacement

pumps while hydrodynamic pumps can be fixed

displacement pumps, in which the displacement

(flow through the pump per rotation of the pump)

cannot be adjusted, or variable, which have a more

complicated construction that allows the

displacement to be adjusted. It will pump the

hydraulic fluid into hose pipes to the respective

hydraulic jacks.

4. Control unit:

Control unit controls the direction and flow of fluid in the system. It

is the major part of the system, the control unit reliefs the excess

pressure and stops the stock of the oil filled the cylinder to return

back. Control unit provides manual and automatic control on the

press and flow of fluid in the system, whether it is from pump to

cylinder or cylinder to tank. It will be the controlling unit which

would decide that in which hose line the hydraulic fluid will flow to

respective hydraulic jack.

Fig 5.2: HYDRAULIC JACK [2]

Fig 5.3: HYDRAULIC PUMP [3]

Fig 5.4: CONTROLVALVE [7]

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5. 12 Volt DC Car Battery:

12 Volt DC battery will give supply to the whole hydraulic jackingsystem.

6. Hose pipes:

These will be the pipe lines will help the fluid to travel from reservoir

tank to pump and pump to hydraulic jacks.

7. DC Motor:

DC motor is a device which converts electrical energy into mechanical

energy. It is used in jack to rotate the hydraulic pump because the current

available at vehicle battery is DC current.

Fig 5.4:12 VOLT DCBATTERY [3]

Fig 5.5: HOSE PIPES[3]

Fig 5.6: DC MOTOR [3]

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5. 12 Volt DC Car Battery:

12 Volt DC battery will give supply to the whole hydraulic jackingsystem.

6. Hose pipes:

These will be the pipe lines will help the fluid to travel from reservoir

tank to pump and pump to hydraulic jacks.

7. DC Motor:

DC motor is a device which converts electrical energy into mechanical

energy. It is used in jack to rotate the hydraulic pump because the current

available at vehicle battery is DC current.

Fig 5.4:12 VOLT DCBATTERY [3]

Fig 5.5: HOSE PIPES[3]

Fig 5.6: DC MOTOR [3]

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5. 12 Volt DC Car Battery:

12 Volt DC battery will give supply to the whole hydraulic jackingsystem.

6. Hose pipes:

These will be the pipe lines will help the fluid to travel from reservoir

tank to pump and pump to hydraulic jacks.

7. DC Motor:

DC motor is a device which converts electrical energy into mechanical

energy. It is used in jack to rotate the hydraulic pump because the current

available at vehicle battery is DC current.

Fig 5.4:12 VOLT DCBATTERY [3]

Fig 5.5: HOSE PIPES[3]

Fig 5.6: DC MOTOR [3]

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Chapter-6

PROPOSED DESIGN FOR THE CONCEPT

Fig 6.1: SCHEMATIC DIAGRAM OF PROPOSED DESIGN

1. 12 Volt DC battery

2. DC Motor

3. Hydraulic pump

4. Hydraulic Fluid Reservoir Tank

5. Control Unit

6. Hydraulic Jack

6.1Left Side Hydraulic Jack

6.2Right Side Hydraulic Jack

7. Pipes

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6.1 Schematic diagram of control unit

Fig 6.2: SCHEMATIC DIAGRAM OF CONTROL UNIT

6.2 Design Process – Lowered and Retracted Hydraulic Jack

1. Lowering of Hydraulic Jack

Fig 6.3: LOWERED JACK

2. Retracting of Hydraulic Jack

Fig 6.4: RETRACT JACK

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6.1 Schematic diagram of control unit

Fig 6.2: SCHEMATIC DIAGRAM OF CONTROL UNIT

6.2 Design Process – Lowered and Retracted Hydraulic Jack

1. Lowering of Hydraulic Jack

Fig 6.3: LOWERED JACK

2. Retracting of Hydraulic Jack

Fig 6.4: RETRACT JACK

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6.1 Schematic diagram of control unit

Fig 6.2: SCHEMATIC DIAGRAM OF CONTROL UNIT

6.2 Design Process – Lowered and Retracted Hydraulic Jack

1. Lowering of Hydraulic Jack

Fig 6.3: LOWERED JACK

2. Retracting of Hydraulic Jack

Fig 6.4: RETRACT JACK

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6.3 Advantages of New Design Concept

1. Man Power is will be minimized.

2. Lifting of vehicle is an easy task

3. Tires can be easily replaced in case of tyre deflation.

4. Repairing and maintenance work is easy.

5. Less maintenance is required for the system.

6. Heat energy dissipated by the system is very less.

7. No manual work will be required for positioning and lifting of jack.

8. When not in use jacks will be retracted back in the chassis.

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Chapter-7

METHOD USED FOR PROPESED DESIGN

Hydraulics is the science of transmitting force /or motion through the medium of a confined

liquid. In a hydraulic device, power is transmitted by pushing on a confined liquid. The

transfer of energy takes place because a quantity of liquid is subject to pressure. To operate

liquid-powered systems, the operator should have knowledge of the basic nature of liquids.

Hydraulic jacks work on the basis of Pascal's Principle, named for Blaise Pascal, who lived

in the seventeenth century.

Basically, the principle states that the pressure in a closed container is the same at all points.

Pressure is described mathematically by a Force divided by Area. Therefore if you have two

cylinders connected together, small one and a large one, and apply a small Force to the small

cylinder, this would result in a given pressure. By Pascal’s Principle, this pressure would be

the same in the larger cylinder, but since the larger cylinder has more area, the force emitted

by the second cylinder would be greater. This is represented by rearranging the pressure

formula P= F/A, to F = PA.

Fig 7.1: PASCAL’S PRINCIPLE [2]

The pressure stayed the same in the second cylinder, but Area was increased, resulting in a

larger Force. The greater the differences in the areas of the cylinders, the greater the potential

force output of the big cylinder. A hydraulic jack is simply two cylinders connected.

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An enclosed fluid under pressure exerts that pressure throughout its volume and against any

surface containing it. That's called 'Pascal's Principle', and allows a hydraulic lift to generate

large amounts of FORCE from the application of a small FORCE.

For lifting cars in car service station hydraulic jacks are used. High pressure liquid is filled in

the jack cylinder by hydraulic pump, due to the pressure the piston moves up. To lower the

piston valve is provided by which the liquid returns to the hydraulic tank.

Hydraulic Jacks are portable devices used for raising heavy objects by means of force applied

with a lever or screw. The hydraulic jacks are compact and lightweight units that are used for

lifting capacities.

They offer easy operation and are fast acting components. The hydraulic jacks come with

inbuilt release pedal for rapid lowering and lugs that make it easy to mount. The heavy duty

chassis prevents the jack from twisting or bending and foot pump provides fast lift to the

load. It also has a safety overload valve that prevents overloading beyond rated capacity.

Unlike the traditional screw type jack which has to be turned with a long handle, the

hydraulic jack uses oil pressure to displace (lift) the vehicle by mere moving a lever or

handle up and down. This is very easy to operate and with this even a child can operate and

lift a vehicle using the hydraulic jack.

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7.1 Hydraulic Systems

A hydraulic system contains and confines a liquid in such a way that it uses the laws

governing liquids to transmit power and do work and. components of a hydraulic system that

store and condition the fluid. The oil reservoir (sump or tank) usually serves as a storehouse

and a fluid conditioner. Filters strainers and magnetic plugs condition the fluid by removing

harmful impurities that could clog passages and damage parts.

Heat exchanges or coolers often are used to keep the oil temperature within safe limits and

prevent deterioration of the oil. Accumulators, though technically sources of stored energy,

act as fluid storehouses.

If we consider a hydraulic system which is used in earth moving equipment like hydraulic

excavators use one and only one power, i.e. hydraulic power. The excavators control such

as bucket lifting arm swiveling, boom swiveling and extension all this actions are controlled

by hydraulic circuits. To know more about the hydraulic system we will see it with closer

view. First comes an oil tank or reservoir in which hydraulic oil is stored. The oil passes

through various pipelines and after doing useful work in an actuator the oil returns back to

the oil tank. Then filter that filter soil before going to next element, i.e. pump.

Hydraulic pump which creates the flow of oil under pressure through entire hydraulic system.

Hence assist transfer of power from which we get useful work. The valves which are fluid

control element are of different types, direction control valves, flow control valves, pressure

relief valves. These valves drive the flow of oil in the system. In actuators (linear) the

pressurized oil acts. The oil gives or transmits its

power to actuators to carry out work. The

pipeline which is the functional connection for

oil flow in the hydraulic system.

Now applying the system to lift the car from one

side so that wheel will be resting on the three

points, one is the piston rod of the hydraulic

actuator and the two tires. The position of each

element of hydraulic system is to be arranged in

a proper manner so that it should not cause a

drastic change in the four wheeler, which is now

made by the car manufacturer.

Fig 7.2: HYDRAULIC SYSTEM [3]

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22

The position of the hydraulic actuator is fixed. The cylinder will be permanently mounted on

the chassis centrally between two wheels on either side of the car. The oil tank or reservoir,

motor and pump could be arranged away from the cylinder as fluid is used for the transfer of

the power and motion.

7.1.1 Working

The actual working of hydraulic system that lifts the car takes place by single press of the

button provided on dashboard. When the switch is turned on the motor starts running which

is powered by a battery already available in the car. This motor facilitates the flow of oil

which is pressurized by the pump provided. This pressurized oil id then directed to the

control unit which in turn directs the flow. Distribution of the pressurized oil is controlled by

a switch on the dashboard. As the oil proceeds into the hydraulic cylinder, it exerts a certain

amount of pressure on the plunger or the ram inside the cylinder. This exerted pressure of the

oil is converted into a linear force which in turn causes the plunger in the cylinder to move

out of the cylinder. Thus ultimately the exerted pressure of the oil is converted into linear

motion of the plunger. As the plunger downwards out of the cylinder linearly, after a definite

travel of the plunger in the downward direction and once it touches the ground it starts lifting

the car.

Once the car is lifted to a desired height the tires can be changed. It is the specialty of a

simple hydraulic jack that it possesses a self-locking system i.e. once the car is lifted to a

certain height and even if the power to the jack is cut off the jack can still hold the entire part

of car that is lifted by it. And thus, the driver can easily change the tire.

Once the tire is changed, now the concern is to release the pressure in the jack which is in the

form of pressurized oil. Thus a relief valve is provided on the jack for this purpose. But since

it is impossible to actuate this valve manually when this jack is installed on the chassis, this

valve is then provided on the dashboard of the car in form of a switch which controls the

relief valve provided on the control unit of the system. Once the relief valve is opened the oil

in the cylinder which has lost its pressure energy, starts returning to the control unit. Once the

oil starts returning the control unit then sends the accumulated oil back to the oil sump. And

in this way the entire system efficiently works.

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7.2 Construction of Components

7.2.1 Hydraulic CylinderA hydraulic actuator receives pressure energy and converts it to mechanical force and

motion. An actuator can be linear or rotary. A linear actuator gives force and motion outputs

in a straight line. It is more commonly called a cylinder but is also referred to as a ram,

reciprocating motor, or linear motor. A rotary actuator produces torque and rotating

motion. It is more commonly called a hydraulic motor or motor.

Cylinders are linear actuators which convert fluid power into mechanical power. They are

also known as JACKS or RAMS. Hydraulic cylinders are used at high pressures and

produce large forces and precise movement. For this reason they are constructed of strong

materials such as steel and designed to withstand large forces.

7.2.2 Construction and Working of Cylinder

The cylinders fabricated for the jack have a sleeve in which the piston reciprocates while

operation. The cylinder material is cast iron and welded with an iron base plate. The plate is

gas welded below the hollow cast iron cylinder. There is an opening for oil in the base of

cylinder.

A cast iron head cover is designed for covering the cylinder from upper end. The piston have

an oil rubber ring to seal the fluid in cylinder while operation. The piston rod is fitted with the

piston and screw not on other end. The head cover is locked with the help of circlip lock. A

hole is made in the head cover to release air from the upper hollow portion of cylinder while

reciprocating motion.

When fluid (oil) pushed by the pump into the cylinder from the inlet opening given below, it

pushes the piston up in the cylinder and thus linear motion is obtained by displacement of

piston in the cylinder.[4]

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7.2.2.1 Cylinder Specification

Cylinder internal diameter : 55mm

Cylinder outer diameter : 73mm

Stroke : 140mm

Volume of cylinder : 332.61ml

Base plate diameter : 115mm

Piston length : 15mm

7.2.2.2 Design Consideration

Lifting capacity: 600kg

Pump max pressure :25 bar @ 1200 rpm

254929.05kgf/m'

600 =254929.05 x 3.14 x r2

r = .0275 m= 27.5 mm

Therefore Diameter,r x 2 = 55 mm

(Approx.55 mm considered)

W=PxA

Fig 7.3: HYDRAULICCYLINDER [4]

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7.3 Hydraulic Pump

Hydraulic pumps convert mechanical energy from a prime mover (engine or electric motor)

into hydraulic (pressure) energy. The pressure energy is used then to operate an actuator.

Pumps push on a hydraulic fluid and create flow. A rotary vane pump is used in the jack to

create the pressure difference in fluid medium. Hydraulic pumps are used in hydraulic drive

systems and can be hydrostatic or hydrodynamic. Hydrostatic pumps are positive

displacement pumps while hydrodynamic pumps can be fixed displacement pumps, in which

the displacement (flow through the pump per rotation of the pump) cannot be adjusted,

or variable displacement pumps, which have a more complicated construction that allows the

displacement to be adjusted.[5]

7.3.1 Types of Hydraulic Pump

7.3.1.1 Variable Delivery Vane Pump

The principles are the same but adjusting items (1) and (3) on the diagram can change the

eccentricity of the ring relative to the rotor. This enables the quantity of oil being pumped to

be set to a required value. The pump can be designed so that as the pressure increases beyond

a set limit, it forces the ring to a concentric position and reduces the flow to zero thus

protecting the pump. Pumps with variable delivery such as the eccentric ring vane pump,

may be designed to reduce their flow as the pressure rises.

The symbol indicates that the outlet pressure

acts on the eccentric ring and pushes it against

an opposing spring so that as the pressure rises

the ring gradually becomes concentric and the

flow is reduced. In many systems we do not

want the flow to decrease with pressure until a

dangerous pressure is reached. In this case a

simple pilot operated valve is used which opens

at a preset pressure and allows the ring to be

centralized.Fig 7.4: VARIABLE DELIVERY VANE

PUMP [5]

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7.3.1.2 Radial Piston Pump

There are many designs for radial piston

pumps. The design shown below has three

pistons (3) arranged around an eccentric

cam (2). The cam is part of the main shaft

(1) and when it rotates the pistons are made

to reciprocate inside cylinders (4) which

lay on a radial line. When the piston moves

inwards the space in the cylinder fills with

oil through the suction valve (7) and the

suction port (s). When the piston moves

outwards, the oil is trapped inside and forced out to the pressure port (p).

7.3.1.3 Gear Pump

These are very common and have only two moving parts. The input shaft (3) carries the

driving gear (7) that turns the idler gear (8). Oil from the suction port is carried around in the

space between the gears and at the pressure port the gears mesh and form a barrier so the oil

is forced out.

Fig 7.6: GEAR PUMP [5]

Fig 7.5: RADIAL PISTON PUMP [5]

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7.3.1.4 Rotary Vane Pump

A rotary vane pump is a positive-displacement pump that consists of vanes mounted to a

rotor that rotates inside of a cavity. In some cases these vanes can be variable length and/or

tensioned to maintain contact with the walls as the pump rotates.

In a vane-type pump, a slotted rotor splined to a drive shaft rotates between closely fitted

side plates that are inside of an elliptical- or circular-shaped ring. Polished, inlet as the space

between vanes increases.

The oil is squeezed out at the outlet as the pumping chamber's size decreases. Hardened

vanes slide in and out of the rotor slots and follow the ring contour by centrifugal force.

Pumping chambers are formed between succeeding vanes, carrying oil from the inlet to the

outlet. A partial vacuum is created at the because the normal wear points in a vane pump are

the vane tips and a ring's surface, the vanes and ring are specially hardened and ground. A

vane pump is the only design that has automatic wear compensation built in. As wear occurs,

the vanes simply slide farther out of the rotor slots and continue to follow a ring's contour.

Thus efficiency remains high throughout the life of the pump.[5]

Fig 7.7: ROTARY VANE PUMP WORKING [5]

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7.3.1.5 Construction and Working of Pump

A slotted rotor is eccentrically supported in a cycloidal cam. The rotor is located close to the

wall of the cam so a crescent-shaped cavity is formed. The rotor is sealed into the cam by

two side plates. Vanes or blades fit within the slots of the impeller. As the rotor rotates

(yellow arrow) and fluid enters the pump, centrifugal force, hydraulic pressure, and/or push

rods push the vanes to the walls of the housing. The tight seal among the vanes, rotor, cam,

and side plate is the key to the good suction characteristics common to the vane pumping

principle.[5]

The housing and cam force fluid into the pumping chamber through holes in the cam (small

red arrow on the bottom of the pump). Fluid enters the pockets created by the vanes, rotor,

cam, and side plate.

As the rotor continues around, the vanes sweep the fluid to the opposite side of the crescent

where it is squeezed through discharge holes of the cam as the vane approaches the point of

the crescent (small red arrow on the side of the pump). Fluid then exits the discharge port.

Fig 7.8.1: ROTARY VANE PUMP [5]

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7.3.1.6 Pump Specification

Type : Rotary vane pump

No. of blades : 10

Body Material : Aluminum

Max. Pressure : 35 bar at 1600 rpm

Max. Flow : 16 Lpm (liter per min) at 1600 rpm

Rotation : Clockwise

7.3.1.7 Hydraulic Power

Working Pressure : 25 Bar @1200 rpm

Discharge : 12 Lpm @1200 rpm

So,

Power = (25 x 12) ÷ 600

Power = 0.5 HP

Power = (P x Q) ÷ 600

Fig 7.8.2: ROTARY VANE PUMP [5]

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7.4 Control Unit

Control unit controls the direction of flow and pressure of the fluid in the system. It is a

major part of the system, the control unit reliefs the excess pressure and stops the stock of oil

filled the cylinder to return back. Control unit provides manual and automatic control on the

pressure and flow of oil in the system. Whether it is from pump to cylinder or cylinder to

tank

7.4.1 Construction and Working of Control Unit

The control unit for the jack is fabricated on an aluminum block. Relief valve, release valve

(Manual Shut off valve) and delivery valves (By pass valve) are fitted in the control unit.

Connections are made with the help of steels pipes, robber hose and banjo bolts. When high

pressure fluid enters the control emit it passes through the delivery valve which acts as a one

way valve allows oil to flow from pump to cylinder and restrict the opposite flow of oil

from cylinder to pump.

There is a relief valve fitted between the main gallery and flow gallery the excess pressure

during the operation is drained in the reservoir by the relief valve. There is a return valve

fitted between the delivery and flow lines. This return valve (On-Off valve) is manually

operated valve used to drain the stock of the cylinder.

For making the design work we use the direction control valves. In this case we use 5/2 way

direction valves. A valve is a device that regulates the flow of fluid (gases, liquids, fluidized

solids, or slurries) by opening and closing or partially obstructing passage ways.

Directional control valves are one of the most fundamental parts in hydraulic machinery as

well and pneumatic machinery. They allow fluid flow into different paths from one or more

sources. They usually consist of a spool inside a cylinder which is mechanically or

electrically controlled. The movement of the spool restricts or permits the flow, thus it

controls the fluid flow.

The spool (sliding type) consists of lands and grooves. The lands block oil flow through the

valve body. The grooves allow oil or gas to flow around the spool and through the valve

body. There are two fundamental positions of directional control valve namely normal

position where valve returns on removal of actuating force and other is working position

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31

which is position of a valve when actuating force is applied. There is another class of valves

with 3 or more position that can be spring centered with 2 working position and abnormal

position.

They are widely used in the hydraulics industry. These valves make use of

electromechanical solenoids for sliding of the spool. Because simple application of electrical

power provides control, these valves are used extensively. However, electrical solenoids

cannot generate large forces unless supplied with large amounts of electrical power. Heat

generation poses a threat to extended use of these valves when energized over time. Many

have a limited duty cycle. This makes their direct acting use commonly limited to low

actuating forces.[8]

Often a low power solenoid valve is used to operate a small hydraulic valve (called the pilot)

that starts a flow of fluid that drives a larger hydraulic valve that requires more force.

A bi-stable pneumatic valve is typically a pilot valve that is a 3 ported 2 position demented

valve. The valve retains its position during loss of power, hence the bi-stable name.

Bi-stability can be accomplished with a mechanical detent and 2 opposing solenoids or a

"magna-latch" magnetic latch with a polarity sensitive coil. Positive opens and negative

closes or vice -versa. The coil is held in position magnetically when actuated.

7.4.1.1 5-port 2 way Directional valves

A 5/2 way directional valve from the name itself has 5 ports equally spaced and 2 flow

positions. It can be used to isolate and simultaneously bypass a passage way for the fluid

which for example should retract or extend a double acting cylinder.

There are varieties of ways to have this valve actuated. A solenoid valve is commonly used, a

lever can be manually twist or pinch to actuate the valve, an internal or external hydraulic or

pneumatic pilot to move the shaft inside, sometimes with a spring return on the other end so

it will go back to its original position when pressure is gone, or a combination of any of the

mention above. [8]

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Fig 7.5: CONTROL VALVE [8]

A single solenoid is used and a spring return is installed in the other end. The inlet pressure is

connected to (P)1. (A)2 could possibly be connected to one end of the double acting cylinder

where the piston will retract while (B)4

is connected to the other end that will

make the piston extend. The normal

position when the solenoid is de-

energized is that the piston rod

is blocking (B)4 and pressure coming

from (P)1 passes through (A)2 that will

make the cylinder normally retracted.

When the solenoid is energized, the

rod blocks (A)2 and pressure from (P)1

passes through (B)4 and will extend the

cylinder and when the solenoid is de-

energized, the rod bounces back to its

original position because of the spring

return. (E) 3 and (E) 5 is condemned or used as exhaust.

Fig 7.6: CONTROL VALVE WORKING [8]

32

Fig 7.5: CONTROL VALVE [8]

A single solenoid is used and a spring return is installed in the other end. The inlet pressure is

connected to (P)1. (A)2 could possibly be connected to one end of the double acting cylinder

where the piston will retract while (B)4

is connected to the other end that will

make the piston extend. The normal

position when the solenoid is de-

energized is that the piston rod

is blocking (B)4 and pressure coming

from (P)1 passes through (A)2 that will

make the cylinder normally retracted.

When the solenoid is energized, the

rod blocks (A)2 and pressure from (P)1

passes through (B)4 and will extend the

cylinder and when the solenoid is de-

energized, the rod bounces back to its

original position because of the spring

return. (E) 3 and (E) 5 is condemned or used as exhaust.

Fig 7.6: CONTROL VALVE WORKING [8]

32

Fig 7.5: CONTROL VALVE [8]

A single solenoid is used and a spring return is installed in the other end. The inlet pressure is

connected to (P)1. (A)2 could possibly be connected to one end of the double acting cylinder

where the piston will retract while (B)4

is connected to the other end that will

make the piston extend. The normal

position when the solenoid is de-

energized is that the piston rod

is blocking (B)4 and pressure coming

from (P)1 passes through (A)2 that will

make the cylinder normally retracted.

When the solenoid is energized, the

rod blocks (A)2 and pressure from (P)1

passes through (B)4 and will extend the

cylinder and when the solenoid is de-

energized, the rod bounces back to its

original position because of the spring

return. (E) 3 and (E) 5 is condemned or used as exhaust.

Fig 7.6: CONTROL VALVE WORKING [8]

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7.5 Oil Reservoir

There is a plastic tank fitted in the jack of 700mL volume. The total oil required in the jack

is 500mL. There are two openings in the tank one is connected to the inlet of the pump and

another is connected to the return flow from the control unit .The connections are made with

the help of rubber and steel pipes.

There is a cap on the top of the tank for refilling it. Tank is mounted with the help of thin

metal sheet in the jack. Hydraulic oil of 46 grade is used in the jack. As the pump used is

vane pump so the oil of low viscosity as grade 46 is used.[7]

Table 7.1: ISO OIL GRADE [7]

7.6 Dc Motor

Motor is a device which converts electrical energy into mechanical energy. A DC Motor is

used in the jack to rotate the pump. DC motor is used became the current available at vehicle

battery is DC current. Motor have to terminals positive and negative. Negative terminal of

the motor is itself the body of motor.

7.6.1 Motor Specification

Type : Permanent Magnet DC motor

Power input : 12 Volt DC

Power Output : 0.4KW = 0.5 HP

Rotation : Clockwise

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7.7 Installations

7.7.1 Frame & Base Plate

All the components are mounted with the help of bolts on the iron frame and plate and this

plate is the base plate. The frame is made up of iron square bars.

Frame-1220mm x 762mm x 250mm (L x B x T)

Base Plate- 610mm x 762mm x 10mm (L x B x T)

Wheel- 12 inch plastic (no. of 4)

7.7.2 Connection Pipes

Steel pipes of 8 mm diameter are used for connection between pump and control unit.

Return and inlet pipes are rubber pipes. The cylinder and the control unit is connected with

a flexible hydraulic hose pipe. These hose pipe have maximum working pressure capacity

of 40 Mpa.

7.7.3 Pump and Motor Mounting

Pump and motor are mounted on the base plate with the help of three vertical mounting

plates. These mounting plates are aluminum plates. Pump and motor are mounted such that

in order to provide the proper mating of gears used to transmit the power. A small tolerance

is provided between the gears in order to avoid the interference of teeth and noise.

7.7.4 Control Unit Mounting

Control unit is mounted in the base plate at the delivery side of the pump with the help of a

bolt. The control unit is connected with the tank as return flow with the help of rubber pipe

and also connected with the outlet of the pump with the help of steel pipe.

7.7.5 Hydraulic Fittings and Connection

Components of a hydraulic system [sources (e.g. pumps), controls (e.g. valves) and actuators

(e.g. cylinders)] need connections that will contain and direct the hydraulic fluid without

leaking or losing the pressure that makes them work. In some cases, the components can be

made to bolt together with fluid paths built-in. In more cases, though, rigid tubing or flexible

hoses are used to direct the flow from one component to the next.

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35

Each component has entry and exit points for the fluid involved (called ports) sized

according to how much fluid are expected to pass through it.

There are a number of standardized methods in use to attach the hose or tube to the

component. Some are intended for ease of use and service, others are better for higher system

pressures or control of leakage. The most common method, in general, is to provide in each

component a female-threaded port, on each hose or tube a female-threaded captive nut, and

use a separate adapter fitting with matching male threads to connect the two. This is

functional, economical to manufacture, and easy to service.

7.7.6 Electrical Connection

Electric connections are made with two terminal wires as positive and negative terminals.

Positive terminal wire is an insulated copper wire of thickness 5 mm and 15 feet length. This

wire has a battery clip on one end which is to be connected at the positive terminal of the

battery of the vehicle. A starter switch is fitted for on off operation of the jack. Negative

terminal wire is also a copper wire of thickness 5mm and length 3 feet. This wire is small in

length and also has a clip on one end. This negative terminal wire is connected with jack

body as earth and while operation it is connected to the vehicle body acting as a negative

terminal.

7.7.6 Hydraulic Oil

Power Steering Fluid is hydraulic fluid that is used for hydraulic jack system. It flows

through the hoses and power steering pump. The purpose of this fluid is to provide power for

the system, and to be a sealant and lubricant. Some are made of water; however, most

contains mineral oil. Others are made of canola, rapeseed, and silicone oils.ISO Grade 46 oil

is used and 600ml of oil is kept in the reservoir.

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7.8 Working of Hydraulic Jack System

The cylinder of the jack is placed according to the lifting position of the vehicle. After that

terminal wires are connected according to polarity, positive terminal wire is connected to the

positive terminal of the battery with the help of battery clip, while negative terminal is

connected to the vehicle body at any point near to the jack. Now after connections jack is

ready to lift the load or vehicle. The actual working of hydraulic system that lifts the car

takes place by single press of the button provided on dashboard. When the switch is turned

on the motor starts running which is powered by a battery already available in the car. [3]

This motor facilitates the flow of oil which is pressurized by the pump provided. This

pressurized oil id then directed to the control unit which in turn directs the flow. Distribution

of the pressurized oil is controlled by a switch on the dashboard. As the oil proceeds into the

hydraulic cylinder, it exerts

a certain amount of pressure

on the plunger or the ram

inside the cylinder. This

exerted pressure of the oil is

converted into a linear force

which in turn causes the

plunger in the cylinder to

move out of the cylinder.

Thus ultimately the exerted pressure of the oil is converted into linear motion of the plunger.

As the plunger downwards out of the cylinder linearly, after a definite travel of the plunger in

the downward direction and once it touches the ground it starts lifting the car. Once the car is

lifted to a desired height the tires can be changed. Once the tire is changed, now the concern

is to release the pressure in the jack which is in the form of pressurized oil. Thus a relief

valve is provided on the jack for this purpose.[9]

Fig 7.7: HYDRAULIC JACK SYSTEM WORKING [8]

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37

But since it is impossible to actuate this valve manually when this jack is installed on the

chassis, this valve is then provided on the dashboard of the car in form of a switch which

controls the relief valve provided on the control unit of the system. Once the relief valve is

opened the oil in the cylinder which has lost its pressure energy, starts returning to the

control unit. Once the oil starts returning the control unit then sends the accumulated oil back

to the oil sump. And in this way the entire system efficiently works. Now to lower down the

load on jack the oil filled in the cylinder which tends to keep the vehicle lifted is released

with the help of release valve. The oil filled in the cylinder is drained in the tank and the load

comes down slowly. In this way the oil circulates from cylinder to tank and tank to cylinder

during operation.

Fig 7.8: SCHEMATC DIAGRAM OF HYDRAULIC JACK SYSTEM WORKING

37

But since it is impossible to actuate this valve manually when this jack is installed on the

chassis, this valve is then provided on the dashboard of the car in form of a switch which

controls the relief valve provided on the control unit of the system. Once the relief valve is

opened the oil in the cylinder which has lost its pressure energy, starts returning to the

control unit. Once the oil starts returning the control unit then sends the accumulated oil back

to the oil sump. And in this way the entire system efficiently works. Now to lower down the

load on jack the oil filled in the cylinder which tends to keep the vehicle lifted is released

with the help of release valve. The oil filled in the cylinder is drained in the tank and the load

comes down slowly. In this way the oil circulates from cylinder to tank and tank to cylinder

during operation.

Fig 7.8: SCHEMATC DIAGRAM OF HYDRAULIC JACK SYSTEM WORKING

37

But since it is impossible to actuate this valve manually when this jack is installed on the

chassis, this valve is then provided on the dashboard of the car in form of a switch which

controls the relief valve provided on the control unit of the system. Once the relief valve is

opened the oil in the cylinder which has lost its pressure energy, starts returning to the

control unit. Once the oil starts returning the control unit then sends the accumulated oil back

to the oil sump. And in this way the entire system efficiently works. Now to lower down the

load on jack the oil filled in the cylinder which tends to keep the vehicle lifted is released

with the help of release valve. The oil filled in the cylinder is drained in the tank and the load

comes down slowly. In this way the oil circulates from cylinder to tank and tank to cylinder

during operation.

Fig 7.8: SCHEMATC DIAGRAM OF HYDRAULIC JACK SYSTEM WORKING

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7.9 Maintenance

When the jack is not in use, keep the cylinder piston fully retracted. Store the jack on its base

and in a well-protected area where it will not be exposed to corrosive vapors, abrasive dust,

or any other harmful elements.

Visually inspect the jack before each use. Take corrective action if any of the following

problems are found:

Cracked or damaged housing.

Excessive wear, bending, or other damage.

Loose hardware.

Leaking hydraulic fluid.

Scored or damaged piston rod.

7.10 Safety Precautions

Inspect the jack before each use; do not use the jack if it is damaged, altered, or in

poor condition.

To prevent tipping, set up the jack on a hard, level surface.

The load must not exceed the rated lifting capacity of the jack. Lift only dead weight.

Center the load on the jack saddle, because off-center loads can damage the seals and

cause hydraulic failure.

Use the jack for lifting purposes only. This jack is designed to LIFT loads, not

support loads. Immediately support a lifted load with jack stands.

Use only approved hydraulic fluid, such as 32, 46, 68 Grade Hydraulic Oil or

equivalent.

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39

Chapter-8

REPORTS

8.1 Monthly/Weekly Progress Report

MONTH DESCRIPTION OF PROGRESS

MARCH

Study of Hydraulic Basics and Hydraulic System.

Design and calculations.

Market survey of components required.

APRIL

Design and Fabrication of components.

Buying and installation of components.

Study of directional valve systems.

Repairing of Hydraulic pump.

MAY

Installation of directional valves and testing of mechanism.

Installation of hydraulic fittings and completion of mechanism.

Testing and improvements and calculations for future work.

Table 8.1: MONTHLY/WEEKLY PROGRESS REPORT

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8.2 Cost Report

Estimated cost- Rs 18,000/- to 20,000/-

S No. ITEM NAME QUANTITY PRICE (in RS.)

1 Hydraulic Cylinder 2 5,500/-

2 Hydraulic Pump 1 3,200/-

3 12 V DC Motor 1 3,300/-

4 12 V DC Battery 1 3,500/-

5 Control Valves 2 4,000/-

6 Hydraulic fittings 5 800/-

7 Connection Hose Pipes 12ft 160/-

8 Electrical Wires 6 meters 60/-

9 Hydraulic Oil Reservoir 1 300/-

10 Hydraulic Oil 1 liters 400/-

11 Frame 1 1600/-

12 Wheels 4 500/-

13 Repair - 1,000/-

14 Miscellaneous - 400/-

TOTAL 24,720/-

Table 8.2: COST REPORT

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41

Chapter-9

CONCLUSION

This project as a working hydraulic jack performed well and according to the design it is

working with its full capacity of lifting 1000 kg load. The model is working fine as expected

during design. We all worked in a team to get these positive results. We machined the

components by own and got help from others to fabricate the components like control unit,

cylinder, Base plate, mountings etc.

We thought creatively throughout the project and solved every problem occurred regarding to

project. We used all of our knowledge which we gained in our engineering curriculum. We

used knowledge of Hydraulics, Machining, CAD, and Power Transmission with gears etc.

Overall we are proud of what we have produced. Before we began this project we don't have

much experience with hydraulic machines, metal cutting and power transmission. Overall we

have gained a huge set of skills in areas in which we think will be essential to us further

down the line. And finally it's a team work whatever we achieved.

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42

FUTURE WORK

The arrangement of inbuilt hydraulic jack system is designed for small car in this project

work, but this arrangement can be widely use in future for heavy vehicles also by making

some small modifications in current project.

For continuing this project work on future scale four hydraulic cylinder jacks can be installed

in the chassis of the 4 wheeler. With the installation of four hydraulic cylinder jacks four

direction controlling valves can also be introduced in system. Hydraulic oil i.e. the power

steering oil can be used as the working fluid. An extra reservoir along with other reservoir

can be added in the vehicle.

A hydraulic pump i.e. power steering pump itself and a D.C motor is also to be installed in

the system to run the hydraulic pump by the help of belt or gear power transmission

whichever is suitable according to the condition of space size and the amount of power to be

transmitted. The lifting capacity of the cylinder jacks can be increased either by installing

high capacity cylinder jacks or by increasing the amount of pressure produced by the

hydraulic pump.

In case of light vehicles supply to DC motor can be easily done with the help of car battery

itself by using electrical wires or by connecting the power steering itself with the engine

crank to produce high pressure output in case of heavy vehicles. Use only approved hydraulic

fluid, such as 32, 46, 68 Grade Hydraulic Oil or equivalent.

An inbuilt hydraulic jack system can be easily attached to all currently manufacture

automobile chassis and frames. There is a front suspension hydraulic jack that is mounted

centrally to the front suspension of an automobile between its front wheels. There is also a

rear suspension hydraulic jack that is mounted centrally to the rear suspension of the

automobile between its rear wheels.

The system operates on the hydraulic power. This hydraulic arrangement has many

advantages such as maintenance and servicing of vehicle. With the help of this system the

driving of vehicles will be easy especially for ladies. Arrangement is also very useful for

heavy loading vehicles and a single person can go on a long drive. Whole system is operated

by 12 volt DC battery; hence jacks will also work, when vehicle will not in starting

condition. Both jacks can work simultaneously at a single time also. [11]

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43

Fig 9.1: SCHEMATIC DIG. OF FUTURE DESIGN

1. 12 Volt DC battery

2. DC Motor

3. Hydraulic pump

4. Hydraulic Fluid Reservoir Tank

5. Control Unit

6. Hydraulic Jack

6.1Left Front Hydraulic Jack

6.2Right Front Hydraulic Jack

6.3Left Rear Hydraulic Jack

6.4Right Rear Hydraulic Jack

7. Pipes

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44

Schematic Diagram of Control Unit

Fig 9.2: SC. DIG. OF FUTURE CONTROL UNIT

44

Schematic Diagram of Control Unit

Fig 9.2: SC. DIG. OF FUTURE CONTROL UNIT

44

Schematic Diagram of Control Unit

Fig 9.2: SC. DIG. OF FUTURE CONTROL UNIT

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45

REFERENCES

[1] Types of Jack - http://wiki.seloc.org/a/Jack.

[2] Moline-Illinois, Hydraulic Basis, Deere and Company Service Publications, 1997.

[3] Peter Verdone, The Basic Hydraulic System Theory, Peter Verdone.com, 2012.

[4] Moline-Illinois, Hydraulic Cylinder (Introduction), Deere and Company Service

Publications, 1997 p 4.1.

[5] Moline-Illinois, Hydraulic Pump, Deere and Company Service Publications, 1997 P

3.1.

[6] Dr. R.K Bansal, Hydraulic Intensifier, Laxmi Publications, 2009 p 1044.

[7] SAE ISO Oil Grade Table, www.engineeringtoolbox.com.

[8] Hydraulics & Pneumatics, BOOK 2, CHAPTER 8: Directional Control Valves, Sep

23, 2008.

[9] Mueller Thomas L, Mueller Pamela A, US 07/419, 505, Patents/US4993688, 10 Oct

1989.

[10] Harcourt Smith Clyde, Patents/US2343937 A, May 4, 1942.

[11] Glen Moody, Anderson Jones, Samuel D Gray, Patents/US2473757 A, Feb 7, 1947.