gear shifting final

8/13/2019 Gear Shifting Final

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INDEX

1. Introduction.2. Block Diagram.3. Auto-Cad Design.4. Process Sheet.5. Time Status.6. Trials, Testing, Working.7. Cost Analysis.

Raw material components. Watching Charges. Process Charges.

8. Fabrication Basics & Details.9. Advantages.10. Disadvantages.11. Applications.12. Result13. Reference.


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Introduction:

PNEUMATICS

The word pneuma comes from Greek and means breather wind. The word pneumatics is the

study of air movement and its phenomena is derived from the word pneuma. Today pneumatics

is mainly understood to means the application of air as a working medium in industry especially

the driving and controlling of machines and equipment.

Pneumatics has for some considerable time between used for carrying out the simplest

mechanical tasks in more recent times has played a more important role in the development of

pneumatic technology for automation.

Pneumatic systems operate on a supply of compressed air which must be made available in

sufficient quantity and at a pressure to suit the capacity of the system. When the pneumatic system is

being adopted for the first time, however it wills indeed the necessary to deal with the question of

compressed air supply.

The key part of any facility for supply of compressed air is by means using reciprocating

compressor. A compressor is a machine that takes in air, gas at a certain pressure and delivered the air

at a high pressure.

Compressor capacity is the actual quantity of air compressed and delivered and the volume

expressed is that of the air at intake conditions namely at atmosphere pressure and normal ambient

temperature.


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The compressibility of the air was first investigated by Robert Boyle in 1962 and that

found that the product of pressure and volume of a particular quantity of gas.

The usual written as

PV = C (or) PV = P2V2

In this equation the pressure is the absolute pressured which for free is about 14.7 Psi and is of

courage capable of maintaining a column of mercury, nearly 30 inches high in an ordinary barometer.

Any gas can be used in pneumatic system but air is the mostly used system now a days.

SELECTION OF PNEUMATICS

Mechanization is broadly defined as the replacement of manual effort by mechanical

power. Pneumatic is an attractive medium for low cost mechanization particularly for sequential

(or) repetitive operations. Many factories and plants already have a compressed air system,

which is capable of providing the power (or) energy requirements and the control system

(although equally pneumatic control systems may be economic and can be advantageously

applied to other forms of power).

The main advantage of an all pneumatic system are usually economic and simplicity the latter

reducing maintenance to a low level. It can also have out standing advantages in terms of safety.

Pneumatics is a section of technology that deals with the study and application of pressurized

gas to effect mechanical motion.
http://en.wikipedia.org/wiki/Pressurized_gashttp://en.wikipedia.org/wiki/Pressurized_gashttp://en.wikipedia.org/wiki/Pressurized_gashttp://en.wikipedia.org/wiki/Pressurized_gas


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Pneumatic systems are extensively used in industry, where factories are commonly plumbed

with compressed air or compressed inert gases. This is because a centrally located and

electrically powered compressor that powers cylinders and other pneumatic devices

through solenoid valves is often able to provide motive power in a cheaper, safer, more flexible,

and more reliable way than a large number of electric motors and actuators.

Pneumatics also has applications in indu stry, construction, mining, and other areas.

Pneumatic systems in fixed installations such as factories use compressed air because a

sustainable supply can be made by compressing atmospheric air. The air usually has moisture

removed and a small quantity of oil added at the compress or to avoid corrosion of mechanical

components and to lubricate them.

Factory-plumbed, pneumatic-power users need not worry about poisonous leakages as the gas iscommonly just air. Smaller or stand-alone systems can use other compressed gases which are an

asphyxiation hazard, such as nitrogen - often referred to as OFN (oxygen-free nitrogen), when

supplied in cylinders.

Any compressed gas other than air is an asphyxiation hazard - including nitrogen, which makes

up 77% of air. Compressed oxygen (approx. 23% of air) would not asphyxiate, but it would be

an extreme fire hazard, so is never used in pneumatically powered devices.

Portable pneumatic tools and small vehicles such as Robot Wars machines and other hobbyist

applications are often powered by compressed carbon dioxide because containers designed to

hold it such as soda stream canisters and fire extinguishers are readily available, and the phase

change between liquid and gas makes it possible to obtain a larger volume of compressed gas

from a lighter container than compressed air would allow. Carbon dioxide is an asphyxiant and

can also be a freezing hazard when vented inappropriately.

Both pneumatics and hydraulics are applications of fluid power. Pneumatics uses an easily

compressible gas such as air or a suitable pure gas, while hydraulics uses relativelyincompressible liquid media such as oil. Most industrial pneumatic applications use pressures of

about 80 to 100 pounds per square inch (550 to 690 kPa) . Hydraulics applications commonly use

from 1,000 to 5,000 psi (6.9 to 34 MPa), but specialized applications may exceed 10,000 psi

(69 MPa).
http://en.wikipedia.org/wiki/Industryhttp://en.wikipedia.org/wiki/Factoryhttp://en.wikipedia.org/wiki/Compressed_airhttp://en.wikipedia.org/wiki/Inert_gaseshttp://en.wikipedia.org/wiki/Gas_compressorhttp://en.wikipedia.org/wiki/Pneumatic_cylinderhttp://en.wikipedia.org/wiki/Solenoid_valvehttp://en.wikipedia.org/wiki/Electric_motorhttp://en.wikipedia.org/wiki/Actuatorhttp://en.wikipedia.org/wiki/Dentistryhttp://en.wikipedia.org/wiki/Constructionhttp://en.wikipedia.org/wiki/Mininghttp://en.wikipedia.org/wiki/Asphyxiationhttp://en.wikipedia.org/wiki/Nitrogenhttp://en.wikipedia.org/wiki/Nitrogen#Applicationshttp://en.wikipedia.org/wiki/Oxygenhttp://en.wikipedia.org/wiki/Robot_Wars_(TV_series)http://en.wikipedia.org/wiki/Carbon_dioxidehttp://en.wikipedia.org/wiki/Soda_streamhttp://en.wikipedia.org/wiki/Carbon_dioxide#Useshttp://en.wikipedia.org/wiki/Carbon_dioxide#Useshttp://en.wikipedia.org/wiki/Fluid_powerhttp://en.wikipedia.org/wiki/Hydraulicshttp://en.wikipedia.org/wiki/Pounds_per_square_inchhttp://en.wikipedia.org/wiki/Pascal_(unit)http://en.wikipedia.org/wiki/Pascal_(unit)http://en.wikipedia.org/wiki/Pounds_per_square_inchhttp://en.wikipedia.org/wiki/Hydraulicshttp://en.wikipedia.org/wiki/Fluid_powerhttp://en.wikipedia.org/wiki/Carbon_dioxide#Useshttp://en.wikipedia.org/wiki/Carbon_dioxide#Useshttp://en.wikipedia.org/wiki/Soda_streamhttp://en.wikipedia.org/wiki/Carbon_dioxidehttp://en.wikipedia.org/wiki/Robot_Wars_(TV_series)http://en.wikipedia.org/wiki/Oxygenhttp://en.wikipedia.org/wiki/Nitrogen#Applicationshttp://en.wikipedia.org/wiki/Nitrogenhttp://en.wikipedia.org/wiki/Asphyxiationhttp://en.wikipedia.org/wiki/Mininghttp://en.wikipedia.org/wiki/Constructionhttp://en.wikipedia.org/wiki/Dentistryhttp://en.wikipedia.org/wiki/Actuatorhttp://en.wikipedia.org/wiki/Electric_motorhttp://en.wikipedia.org/wiki/Solenoid_valvehttp://en.wikipedia.org/wiki/Pneumatic_cylinderhttp://en.wikipedia.org/wiki/Gas_compressorhttp://en.wikipedia.org/wiki/Inert_gaseshttp://en.wikipedia.org/wiki/Compressed_airhttp://en.wikipedia.org/wiki/Factoryhttp://en.wikipedia.org/wiki/Industry


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Advantages of pneumatics-

Simplicity of Design And Control

Machines are easily designed using standard cylinders & other components. Machines operate

by simple ON - OFF type control.

Reliability

1.Pneumatic systems tend to have long operating lives and require very little maintenance.

2.Because gas is compressible, the equipment is less likely to be damaged by shock. The gas in

pneumatics absorbs excessive force, whereas the fluid of hydraulics directly transfers force.

Storage

Compressed gas can be stored, allowing the use of machines when electrical power is lost.

Safety

1.Very low chance of fire (compared to hydraulic oil).

2.Machines can be designed to be overload safe.


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Advantages Of Pneumatics over hydraulics-

1.Liquid (as a gas is also a 'fluid') does not absorb any of the supplied energy.

2.Capable of moving much higher loads and providing much higher forces due to the

incompressibility.

The hydraulic working fluid is basically incompressible, leading to a minimum of spring action.

When hydraulic fluid flow is stopped, the slightest motion of the load releases the pressure onthe load; there is no need to "bleed off" pressurized air to release the pressure on the load.

Pneumatic logic systems (sometimes called air logic control ) are often used to control industrial

processes, consisting of primary logic units such as:

And Units

Or Units

'Relay or Booster' Units

Latching Units

'Timer' Units

Sorteberg relay

Fluidics amplifiers with no moving parts other than the air itself

Pneumatic logic is a reliable and functional control method for industrial processes. In recent

years, these systems have largely been replaced by electrical control systems, due to the smaller

size and lower cost of electrical components. Pneumatic devices are still used in processes wherecompressed air is the only energy source available or upgrade cost, safety, and other

considerations outweigh the advantage of modern digital control.
http://en.wikipedia.org/wiki/Spring_(device)http://en.wikipedia.org/wiki/Logical_conjunctionhttp://en.wikipedia.org/wiki/Logical_disjunctionhttp://en.wikipedia.org/wiki/Sorteberg_relayhttp://en.wikipedia.org/wiki/Fluidicshttp://en.wikipedia.org/wiki/Fluidicshttp://en.wikipedia.org/wiki/Sorteberg_relayhttp://en.wikipedia.org/wiki/Logical_disjunctionhttp://en.wikipedia.org/wiki/Logical_conjunctionhttp://en.wikipedia.org/wiki/Spring_(device)


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The pneumatic cylinder will be used to operate the gear. DC battery will be usedfor supply. Solenoid valve will be used to pass pressure to the pneumatic cylinderwhen button is pressed. Pneumatic pressure tank will be used. Relay board will beused to provide supply to the solenoid valve coil. One SV will operate the GEAR inupward fashion & another SV will operate in downward fashion .

Block Diagram :

Battery

Supply

Relay

Switch

Press

Switch

Pneumatic

Pressure SV

SV

Pneumatic Pneumatic

Down Gear Paddle Up


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Working principle:-

The button operated gear shifting is done by pressing the gearpaddle with the help of pneumatic cylinder with piston and solenoidvalve assembly. The pneumatic tank also provided. If the gear to beoperated in increasing order SV 1 will be open with the help of buttonwhich is press with the help of our left hand finger. The number ofevents the button pressed will increase the gear. Care should be takenthat while pressing the gear switch they should also be pressed. If thegear is changing the reverse fashion than press another button whichwill open SV2 and the pneumatic cylinder and the gear will operated indecreasing order. It can repeat cycle .

Technical Specifications:

Sr.

No.

Particulars Description

1 Supply 12V DC

2 Solenoid Valve 5/2 pneumatic, 1/4

3 Cylinder Pneumatic type, 2Kg capacity &

20mm stroke

4 Operation Push switch - push to on.


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POWER SUPPLY

Power supply is the first and the most important part of our project.For our project we require +5v

regulated power supply with maximum current rating 500 mA

Following basic building blocks are required to generated power supply.

230vac Reg.o/p

STEP DOWN TRANSFORMER :

Step down transformer is the first part or regulated power supply .To step down the mains 230V A.C. we require step down transformer.Following are the main characteristic of electronic transformer.

I) Power transformer are usually designed to operate from source oflow impedance at a single freq.

II) It is required to construct with sufficient insulation of necessarydielectric strength.

III) Transformer rating are expressed in volt-amp. The volt-amp of eachsecondary winding or windings is added for the total secondary VA.To this are added the load losses.

IV) Temperature rise of a transformer is decided on two well knownfactors i.e. losses on transformer and heat dissipating or coolingfacility provided unit.

Step Down Rectifier Filter3 Terminal

Vtg. Regulator


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RECTIFIER UNIT:

Rectifier unit is a ckt. Which converts A.C. into pulsating D.C.Generally semi-conducting diode is used as rectifying element due toits property of conducting current in one direction only Generallythere are two types of rectifier.

1. Half wave rectifier2. Full wave rectifier.

In half wave rectifier only half cycle of mains A.C. rectified so itsefficiency is very poor. So we use full wave bridge type rectifier, inwhich four diodes are used. In each half cycle, two diodes conduct ata time and we get maximum efficiency at o/p.

Following are the main advantages and is advantages of a full-wave bridge type rectifier ckt.

ADVANTAGES :

1. The need of center tapped transformer is eliminated.2. The o/p is twice that of center tap circuit for the same secondary

voltage.3. The PIV rating of diode is half of the center taps circuit.

DISADVANTAGES :

1. It requires four diodes.2. As during each half cycle of A.C. input, two diodes are

conducting therefore voltage drop in internal resistance of


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rectifying unit will be twice as compared to center tapcircuit

Filter circuit :

Generally a rectifier is required to produce pure D.C. supply for using at various places inthe electronic circuit, However, the o/p of rectifier has pulsating character i.e. if such a D.C. isapplied to electronic circuit it will produce a hum i.e. it will contain A.C. and D.C. components.The A.C. components are undesirable and must be kept away from the load. To do so a filtercircuit is used which removes (or filter out) the A.C. components reaching the load. Obviously afilter circuit is installed between rectifier and voltage regulator. In our project we use capacitorfilter because of his low cost, small size and litile weight and good characteristic. Capacitors areconnected in parallel to the rectifier o/p because it passes A.C. but does not pass D.C. at all.

Three terminal voltage regulators :

A voltage regulator is a ckt. That supplies constant voltageregardless of change in load current. IC voltage regulators are versatile andrelatively cheaper. The 7800 series consists of three terminal positive voltage

regulators. these ICs are designed as fixed voltage regulator and with adequateheat sink, can deliver o/p current in excess of 1A. These devices do not requireexternal component. This IC also has internal thermal overload protection andinternal short circuit and current limiting protection for our project we use 7805voltage regulator IC.


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Design to step down transformer :

The following information must be available to the designer beforethe commences for the design of transformer.

1. Power output2. operating voltage.3. Frequency Range4. Efficiency and Regulation

Size of core :

Size of core is one of the first consideration in regard of core and windingconfiguration used. Generally following formula is used to find area or size ofcore.

Ai = (p1/0.87)

Where

D3T3 D1

+5V

1GNDD2

2GND

0-10 , 500 mA

230VAC@50HZ

+C1

D4

+C3

7805

1 3VIN VOUT

7812


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Ai = Area of cross section in sq. cm.

P1 = Primary voltage

In Transformer P1 = P2

For our project we required +5V regulated output. So transformersecondary rating is 12V, 500 mA.

So secondary power wattage is,

P2 = 12 X 500 X 10 3 w.

= 6w.

so ,

Ai = (6/0.87)= 2.62

Generally 10% of area should be added to core accommodate all turns for lowIron losses and compact size.

So,

Ai = 2.88.

Turns per volt

Turns per volt of transformer are given by relation

10,000

Turns/volt = -------------------


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4.44f B Ai

Here;

F is the frequency in Hz

B is flux density in Wb/m2

A is net area of cross section.

For project for 50Hz the turns per volt for 0.91 wb/m2,

Turns per volt = 50/Ai

= 50/ 2.88

= 17

Thus for primary winding = 220 X 17 = 3800.

For secondary winding = 12 X 17 = 204

Rectifier design :

R. M. S. Secondary voltage at secondary of transformer is 12V. So, maximumvoltage Vm across Secondary is

= RMS voltage *1.41

= 12* 1.41

=16.97

D.C. output voltage at rectifier o/p is

Vdc = 2Vm/3.14

= 2*16.97/3.14


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= 10.80 v

PIV = 2 Vm

= 2 X 16.97

= 34V

Design of filter capacitor

Formula for calculating filter capacitor is,

1

C = -----------------------------

4. 3 r f RL

r = ripple present at o/p of rectifier.

(Which is maximum 0.1 for full wave rectifier ?)

f = Frequency of mains A.C.

R = I/p impedance of voltage regulator IC.

1

C = ------------------- = 1000F

4 3 0.1*50*28


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IC 7805 (Voltage regulator IC):-

Specifications :-

Available o/p D.C.voltage = + 5V Line regulation = 0.03 Load regulation = 0.5 Vin maximum = 35 V Ripple Rejection = 66-180(db)


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1.5 NEED FOR AUTOMATION-

In most of the garages the vehicles are gear changed by using ordinary system. In order to avoid all such

disadvantages, this automatic gear changer has been designed in such a way that it can be used to

change the gear the vehicle very smoothly without any impact force. The operation is made be simple

that even any person can handled, by just pressing the button.

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 an essential part of the system although with

changing demands on physical input as the degree of mechanization is increased.

Degrees of automation are of two types, viz.

1. Full automation.

2. Semi automation.

In semi automation a combination of manual effort and mechanical power is required where as in full

automation human participation is very negligible.

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

sources, pneumatics form an attractive medium for low cost automation. The main advantages of all

pneumatic systems are economy and simplicity. Automation plays an important role in mass production.

1. To achieve mass production

2. To reduce man power

3. To increase the efficiency of the plant

4. To reduce the work load

5. To reduce the production cost

6. To reduce the production time

7. To reduce the material handling


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PRODUCTION OF COMPRESSED AIR -

Pneumatic systems operate on a supply of compressed air, which must be made available,

in sufficient quantity and at a pressure to suit the capacity of the system. When pneumatic system is

being adopted for the first time, however it wills indeed the necessary to deal with the question of

compressed air supply.

The key part of any facility for supply of compressed air is by means using reciprocating

compressor. A compressor is a machine that takes in air, gas at a certain pressure and delivered the air

at a high pressure.

Compressor capacity is the actual quantity of air compressed and delivered and the volume

expressed is that of the air at intake conditions namely at atmosphere pressure and normal ambient

temperature.

Clean condition of the suction air is one of the factors, which decides the life of a compressor.

Warm and moist suction air will result in increased precipitation of condense from the compressed air.

Compressor may be classified in two general types.

1. Positive displacement compressor.

2. Turbo compressor

Positive displacement compressors are most frequently employed for compressed air plant and

have proved highly successful and supply air for pneumatic control application.


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The types of positive compressor

1. Reciprocating type compressor

2. Rotary type compressor

Turbo compressors are employed where large capacity of air required at low discharge

pressures. They cannot attain pressure necessary for pneumatic control application unless built in

multistage designs and are seldom encountered in pneumatic service.

RECIPROCATING COMPRESSORS

Built for either stationary (or) portable service the reciprocating compressor is by far the

most common type. Reciprocating compressors lap be had is sizes from the smallest capacities to

deliver more than 500 m/min. In single stage compressor, the air pressure may be of 6 bar

machines discharge of pressure is up to 15 bars. Discharge pressure in the range of 250 bars can

be obtained with high pressure reciprocating compressors that of three & four stages.

Single stage and 1200 stage models are particularly suitable for pneumatic applications , with

preference going to the two stage design as soon as the discharge pressure exceeds 6 bar , because it in

capable of matching the performance of single stage machine at lower costs per driving powers in the

range .

CHARACTERISTICS OF COMPRESSED AIR:

The greatest advantage of pneumatic system is the availability of working medium free

of cost and it plentiful. Compressed air can also be transported easily and can be easily stored in

a reservoir. Another notable advantage is the insensitiveness of compressed air to temperature

fluctuations. It ensures reliable operation even under extreme conditions of temperature.


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Compressed air offers no risk of explosion; hence no expensive protection cost is required.

Compressed air is a very fast working medium where speed and force are infinitely variable.

CHARACTERISTICS OF PNEUMATICS:

1. Compressibility

A pneumatic fluid is compressible. Compressibility plays a major role in the actuation of

piston, i.e., opening a valve does not move the piston immediately, rather sufficient fluid must

flow into the volume to increase the pressure until the force overcomes that on the other side.

Compressibility is the energy storage of a fluid. As it is possible to store compressed

fluids and transport them, pneumatics has the advantage of transportability. Another advantage

of the energy storage capacity is the small compressor charging a tank can supply a system

having high peak loads but small average loads.

2. Leakage Sealing Problems

Several methods are used to minimize leakage. One is to use a low operating pressure.

Another method to prevent leakage is sealing. Good sliding and rotating sealing are to obtain in

pneumatics is because of low viscosity of the fluids Diaphragms and bellows are used to avoidsliding seats.

3. Low Viscosity:

A highly uncounted problem due to low viscosity is that of sealing. They provide less

viscous damping due to low viscosity hence sliding parts wear considerably. This adds the

necessity for external sources of lubrication.

Another problem is that the pneumatic cylinder should be thinner enough to maintain a

laminar flow inside.


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1. Low Density

Fluids especially gases are usually of low density. Low density fluids require large

mechanical work and more time for high pressure build up.

2.

Wide Range of TemperaturesThe limitations often may lead to a view point that the use of pneumatic equipment is

coupled with high cost. It is proved to be false, however, since a calculation of production cost

includes not only the power cost but also all other compared with wages, installation cost, and

maintenance cost that they are insignificant.

3.3. ADVANTAGES OF PNEUMATIC SYSTEM OVER OTHER SYSTEM:

1. Output power of the pneumatic system can be easily controlled

2. Pneumatic system is not affected by over loading

3. The pneumatic system can be used at various working temperature

4. Air can be easily distributed through pipelines over very long distances

5.

Pneumatic enables high working speeds6. It is a maintenance free system

7. Pneumatic enables the application of force very gently which is not only beneficial to

pneumatic components but also the equipment which they are installed.


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WORKING OF 3/2 SINGLE ACTING SOLENOID (OR) CUT OFF VALVE:

The control valve is used to control the flow direction is called cut off valve or solenoid valve.This solenoid cut off valve is controlled by the emergency push button. The 3/2 Single acting solenoid

valve is having one inlet port, one outlet port and one exhaust port. The solenoid valve consists of

electromagnetic coil, stem and spring. The air enters to the pneumatic single acting solenoid valve when

the push button is in ON position.

A pneumatic shifter works through compressed air power. So when it receives the signal

that gears need to be changed, the shifter opens or closes a magnetic valve assembly. This valve

allows compressed air into the system, or pushes it out, in order to create the effect of shiftinggears. If more compressed air is allowed in, then the gear is shifted up. If compressed air is let

out, then the gear is shifted down. This compressed air can come from an on-board tank or from

re-routed engine exhaust, depending on the particular design of the pneumatic shifter.

In the general electronic pneumatic shift system, a lever position sensor 6 detects an operation

of a gearshift lever 4L by the driver. The lever position sensor 6 outputs electrical signals corresponding

to a changing position of the shift lever 4L to an electronic control unit (ECU) 8, and the ECU 8 outputs

signals to control opened and closed states of a magnetic valve assembly 10 according to the signals

received from the lever position sensor 6. Accordingly, air is supplied to or exhausted from a shift

control device 12 to control a transmission 14 into various forward and reverse shift modes.

The magnetic valve assembly 10 is connected to an air tank 15 and receives the supply of air

from the air tank 15. Also, by the supply and exhaust of air from and to the air tank 15 via a reaction

valve 18, which is a 3-way magnetic valve connected to a reaction cylinder (not shown), a shift feeling is

provided to the driver when the gearshift lever 4L is manipulated to different shift modes.

The ECU 8 is connected to a shift mode display 20, and the ECU 8 performs control such that the shift

mode display 20 displays the present shift mode after receiving signals from the lever position sensor 6.

The ECU 8 is also connected to a warning lamp 24 which alerts the driver either of either shift failure

caused by the incorrect supply of air to the magnetic valve assembly 10, or of the mis-operation of the

gearshift lever 4L by the driver.
http://www.patentstorm.us/patents/6196077/description.htmlhttp://www.patentstorm.us/patents/6196077/description.htmlhttp://www.patentstorm.us/patents/6196077/description.htmlhttp://www.patentstorm.us/patents/6196077/description.htmlhttp://www.patentstorm.us/patents/6196077/description.htmlhttp://www.patentstorm.us/patents/6196077/description.html


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The shift control device 12 includes a cylinder MVA 26 and a cylinder MVB 28. Air is supplied

to and exhausted from the cylinder MVA 26 and the cylinder MVB 28 by the operation of the magnetic

valve assembly 10 which operates according to signals output from the ECU 8. A shift rod 30 is slidably

disposed in the shift control device 12. The shift rod 30 is displaced in a rightward or leftward direction

(in the drawing) according to the supply of air to the cylinder MVA 26 and the cylinder MVB 28.

A striker 32 is fixedly disposed on the shift rod 30. With this configuration, when the shift

rod 30 is displaced in the leftward direction, the striker 32 is also moved such that it operates the

transmission 14 to either a first, third or fifth speed of a drive D range; and when the shift rod 30 is

displaced in the rightward direction, the striker is moved such that it operates the transmission 14 to

either a second or fourth speed of the drive D range, or into reverse. That is, when the driver operatesthe gearshift lever 4L to different shift modes, the ECU 8 controls the magnetic valve assembly 10 so

that air is supplied to or exhausted from the cylinder MVA 26 and the cylinder MVB 28 of the shift

control device 12, thereby controlling the displacement of the shift rod 30 and the striker 32.

Also, provided on one end of the shift rod 30 is a magnet 34. Magnet sensors 36 are mounted

in the shift control device 12 corresponding to a position of the magnet 34. Accordingly, the magnet

sensors 36 are able to detect the changing position of the magnet 34 as the shift rod 30 is displaced.

However, in the general pneumatic shift system as described above, since air pressure is

used to shift the transmission 14 into different shift modes, in the case where air is abruptly supplied to

the shift control device 12, the shift rod 30 and striker 32 are moved at a substantial speed such that

abrupt force is applied to a synchronizer, shift fork, etc. of the transmission 14. This results in the wear

of the transmission 14, as well as a reduction in shift and ride quality caused by shift shock.
http://www.patentstorm.us/patents/6196077/description.htmlhttp://www.patentstorm.us/patents/6196077/description.html


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PCB Design:

Designing of PCB:I) After selection of electronic circuit, make a block diagram of various

circuits to know various inter-connections required, which will help inreducing the number of wires.

II) The designer should have the complete idea of the circuit regardingthe function and signal flows through.

III) Keep each and very component you need, while starting thedesigning.

IV) Use of templates is essential if you are new designer, if the design is

manual i.e. hand made and not with software such as Orcas, AutoCAD, Pads, Ideas, Circuit maker, etc.V) Standard PCB size should be decided in the beginning only.VI) Preferably, layout and artwork should be in 1:2 scales.VII) Sequential stage after PCB size is decided.VIII) Component placement.IX) Track routing i.e. layout.X) Artwork making with ink or ready made tapes and pads.XI) While routing the tracks, carrying AC mains voltage, consider the

safety rules and regulations.XII) In analog and digital systems together, care should be taken thatanalog and digital ground will not mix each other affecting thestability and fluctuations in the display.

XIII) In power system i.e. high current, the track width and the trackspacing should be as maximum as possible.

XIV) While placing the components on the PCB preferably the load onPCB, should be evenly distributed to avoid the problems atcompletion stage during wave-soldering i.e. warping of PCB etc.

XV) To avoid weakening of the pup tool, the perforation length should bekept minimum i.e.


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Component Placement:

I) Preferably, place the component in X-Y direction subjected tomechanical construction.

II) All components should be flat mounted i.e. flat placed to avoidof leads and for easy requirements. However in case of spacelimitation the components such as resistors, diodes, etc. maybe mounted vertically which doesnt affect the performance.

III) In case separate analog and digital ground.IV) Orientation of multi-lead components(e.g. switches, Ics)

should be connected in between the analog and digital ground.V) Sufficient clearance is provided around component so that

inversion or replacement and repair is easy.VI) The design should such that minimum jumpers are allowed.VII) It is preferable that, components like present, coils, and trim

pots, etc. which alignment of calibration are placed in suchthat, they are accessible after the assembly of the PCB oncabinet also.

VIII) If the components are not flush mounted, provide the sleevefor leads.


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Cost Estimation: The cost estimation of the project consists of raw material cost,

machining cost and processing cost. It can be demonstrated as below.

1. Fabricated Fixture 01 = 800/-2. Gear assembly

Pneumatic Valve 5/2 2 1200=2400/-3. 24V Powre Supply 500/-4. PU Pipe 200/-5. DPDT Switch 50/-6. PCB 300/-7. Transformer 500/-8. Relay Board 400/-9. Relay Driver 100/-10. LEDs 10/-11. Diodes 20/-12. Pneumatic Cylender 21200=2400/-

13. Machining Charges 300/-

14. Fabrication Charges 300/-

15.fitting & assesories 02 X 200 = 400/-

16.Processing Charges 250/-

17.Designing Charges 500/-

18.Miscellaneous 500/-

Miscellaneous includes development; extra procured components as wellas damaged components during development .


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Component List:

Sr.

No.

Particulars Qty

(in Nos.)

1 Fabricated stand 01

2 Valve 04

3 24V Supply 01

4 PU Pipe 1 Bundle

5 DPDT Switch 02

6 hardware ---

7 Diodes 048 Resistor 04

9 Transistor 02

10 PCB 1 set

11 LEDs 02

12 Relays 06

13 Transformer 01

14 Mounting Ply 1 piece


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Time Study:

1 Project Selection 15 days2 Block diagram planning 20 days3 Auto cad drawing 20 days4 Material Procurement 1 month5 Machining of accessories 08 days6 Fabrication of assembly 15 days7 Trials & Troubleshooting 15 days8 Testing 10 days9 Electronic Circuit development&

Troubleshooting20 days

10 Documentation 10 days12 Conclusion 01 hour


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Testing And Troubleshooting:

Before soldering in components:

Check that component agree with the parts list (value and power ofresistors, value and voltage rating of capacitor, etc.) if in any doubt doublecheck the polarized components (diodes, capacitor, rectifiers etc)

If there is a significant time elapse between circuit, take the trouble to readthe article; the information is often given in a very condensed from. Try toget most important point out of the description of the operation of thecircuit, even if you dont understand exactly what is supposed to hap pen.

If there is any doubt that some component may not be exact equivalent,check that they are compatible.

Only use good quality IC sockets. Check the continuity of the tracks on the PCB (and through plated holeswith double sided boards) with a resistance meter or continuity tester.

Make sure that all drilling, filling and other heavy work is done beforemounting any components.

If possible keep any heat sinks well isolated from other components. Make a wiring diagram if the layout involves lots of wires spread out in all

directions. Check that the connectors used are compatible and that they are mounted

the right way round. Do not reuse wire unless it is of good quality. Cut off the ends and strip it a

new.

After mounting the component:

Inspect all soldered joints by eye or using a magnifying glass and checkthem with a continuity tester. Make sure there are no dry joints and notracks are short circuited by poor soldering.

Ensure that the positions of all the component agree with the mountingdiagram

Check that any links needed are present and that they are in the rightpositions to give the desired configuration.


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Check all ICs in their sockets (see that there are no pins bent under any ICs,no near ICs are interchanged etc.)

Check all the polarized components (diodes, capacitor etc) are fittedcorrectly.

Check the wiring (watch for off cuts of components leads) at the same timeensure that there are no short-circuits between potentiometer, switches,etc. and there immediate surrounding (other components or the case). Dothe same with mounting hardware such as spacers, nuts and bolts etc.

Ensure that the supply transformer is located as closely as possible to thecircuits (this could have a significant improvement in the case of criticalsignal level).

Check that the connections to the earth are there and that they are of goodcontact.

Make sure the circuit is working correctly before spending any time puttingit into a case.

And if it breaks down:

Recheck everything suggested so far. Re-read the article carefully and carefully anything about which you are

doubtful. Check the supply voltage or voltages carefully and make sure that they

reach the appropriate components especially pins of the ICs (test the pinsof ICs and not the soldered joints).

Check currents (generally they are stated on the circuit diagram or in thetext). Dont be too quick to suspect the ICs of overheating.

If possible check the operation of the circuit in the separate stages as ageneral rule follow the course of the signal.

While checking voltages, currents, frequencies or testing the circuits withan oscilloscope work systematically and take notes.

And dont forget to switch the power on and check the fuses.


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ADVANTAGES-

1. It requires simple maintenance cares

2. The safety system for automobile.

3. Checking and cleaning are easy, because of the main parts are screwed.

4. Easy to Handle.

5. Low cost automation Project

6. Repairing is easy.7. Replacement of parts is easy.

DISADVANTAGES-

1. Initial cost is high.

2. The system is complicated one.

APPLICATIONS-

1. It is very much useful for Car Owners & Auto-garages.

2. Thus it can be useful for the two wheeler application


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RESULT

The pneumatic gear changer was designed and checked for successful working. It was

fount to be running successfully under all the conditions.


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gear shifting final

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