FIELD OF INVENTION:-
The invention relates to a clutch booster mountable in an automobile havina a
clutch. ^
PRIOR ART:-
In a vehicle, a driver uses the clutch system to engage and disengage the transmission system from the vehicle engine. A clutch is useful for a smooth transition when starting, idling in neutral, when shifting gears and also when stopping. The clutch assists in engine power being applied gradually when the engine is running and cuts it when shifting gears to avoid gear crunching. When the clutch is engaged, the power is transferred from the engine to the transmission system and drive wheels. When disengaging the clutch, power is not transferred, thereby allowing the engine to run without stopping.
The clutches are useful in disengaging/engaging the two rotating shafts. In a vehicle, the clutch is used because the engine spins all the time but the wheels do not. To stop the vehicle without the killing /stopping the engine, the wheels need to be disconnected from the engine. The clutch allows smooth engaging of a spinning engine to a non-spinning transmission line by controlling the slippage between them. In a typical clutch the flywheel connects to engine and a clutch plate connects to the transmission. When foot is off, a clutch pedal, a set of springs pushes the pressure plate against clutch disc which in turn presses against flywheel. This locks the engine to the transmission input shaft causing them to spin at the same speed.

As explained the clutch booster essentially assist in the operation of the clutch system which is easily achieved with assistance of air, i.e. the engagement and disengagement of transmission system from the engine. The typical arrangement receives the hydraulic fluid under pressure from a clutch master cylinder which acts as a source of fluid pressure for engaging and disengaging the system,
OBJECTS OF THE INVENTION:-
1) The first object is to reduce slackness of poppet valve during opening in the horizontal direction leads to variation in the air transfer pressure resulted in less output clutch force. This is the first suffering noticed in prior art which the invention attempts to overcome.
2) The second object is to modify the Vehicle Installation - Since bleed screw
provision is placed on top leading to fouling with vehicle chassis portion. Hence leading to repositioning of chassis member on vehicle. Secondly the bleed screw location is not feasible to bleed hence leading to air trap. This is the second suffering noticed in prior art which the invention attempts to overcome.
DESCRIPTION OF INVENTION:
The invention relates to a novel booster system of a clutch booster used to engage and disengage the clutch of a vehicle having a manual gear control system. The system relates to actuating the clutch assembly of a manual transmission vehicle. A typical vehicle will have a clutch pedal mounted near the drivers left/right foot. The clutch pedal will be linked to a clutch fork/lever in a manual by a mechanical linkage. The driver will use his foot to engage and disengage the clutch

assembly. So the performance of a dutch is primarily dependent on the driver's ability to perform on the clutch.
The disadvantages and limitations of the prior art has been overcome in the invention ie. reduce clutch pedal force and increase comfort-ability for driver. Especially applied for vehicles that have large tonnage or driving torque, as installing this component, its costs have risen.
Serial I PART NAME I PART NO
no _ _
1. Control valve body 1
_2. Hydraulic chamber 2
_3. Air chamber _3__
_4 Hydraulic piston 4
^ Air piston 5
6. Air cylinder 6
7. Transfer pipe 7
8. Relay piston 8
9, Poppet valve 9
10. Conical spring 10
11 ■ Push rod r\
12. Air breather 12
13. Bleed screw 13
14. Single mould 14
15. Wire mesh filter 15_
16. Plate type filter(washer) 16
17. Set of slots 17
18. Check valve body 18
19. Fluid inlet port B
20. I Air inlet port | A
When the clutch pedal is pressed and the clutch master cylinder operated, fluid pressure increases at port B. The fluid acts on piston and also ^O\NS though to act on relay piston. As the pressure increases, the push road will travel forward. When the push road meets resistance the fluid pressure will increases and move relay piston, which in turn will lift the poppet valve. Air then flows from port A through

the transfer pipe and acts on the main piston, compounding the force already on the push rod from the hydraulic piston.
The clutch booster is connected with the air reservoir for ancillary consumers via A and with the pedal operated hydraulic master cylinder via B.
Some of precautions have been taken while designing the structure of the invention are as follows:
1. Mounting orientation of clutch booster should be easy for bleeding to avoid air lock,
2. Exhausting the air pockets of clutch booster should be done completely.
3. Selection of brake fluid for clutch booster, which should be compatible with DOTS and DOT4 standard.
4. Selection of length of pushrod to suit vehicle installation.
As installing this component, the system should be added a new tube line to connect clutch booster and rearrange hydraulic pressure line of master cylinder. According to the selected clutch booster size and stroke, the air consumption is no more than 0,3 L per application.
Unlike all known prior art with horizontal arrangement, this invention relates to a clutch booster and relates to vertical arrangement (Fig 2) of air inlet with respect to the assembly axis to overcome the difficulties during the installation as in the case of conventional clutch booster. Due to shift in the air inlet, the overall height of the

assembly becomes compact. The possibilities of leak at the various places were prevented by making the hydraulic portion and air portion as the single cast body. Breather assembly is provided with mesh arrangement which controls / protects the entry of foreign particles/materials and prevents entry of water /mud there by functioning of clutch booster is normal and smooth,
(Fig 2} explains briefly an arrangement of shift of the air inlet provided in the control valve body (1). The poppet valve (9) actuated by the relay piston (8) controls the opening and closing of supply of air pressure to the air cylinder (6) according to the hydraulic fluid pressure from the clutch master cylinder (Not illustrated) supplied into the control valve body (1) by applying of the clutch pedal (Fig 6). The supply of air through port A pushes the air piston (5) in the air cylinder (6) through air transfer pipe (7). Since the air inlet arranged as vertical, the rise of poppet valve (9) becomes vertical and against the gravity. So it makes the return of poppet valve (9} becomes faster and easier on the disengagement of clutch pedal.
The air inlet arrangement (Fig 2) was made vertical to avoid slackness during opening of poppet valve (9). The poppet is a valve having the circular head with elongated stem attached in the center and designed to pop up and down to open and close the air transfer. The poppet valve (9) was placed on the periphery in the check valve body (18) with aid of conical spring force (10) and supported by gravitational force. The opening of poppet valve (9) was made vertical and against the gravity. So the return of poppet valve (9) to its original position on the release of clutch pedal (Not illustrated) was become faster. Also the change in air inlet

arrangement resulted in decrease of overall height as that of conventional clutch booster which facilitates the easy installation in the vehicle.
Bleed screw (13) position (Fig 1) was placed in the control valve body (1) in such a way that the bleed screw would not foul with cross member {not illustrated) during installation in the vehicle- The bleed screw (13) position is designed to accommodate for installation in both planes by maintaining at the top,
(Fig 2) shows the air transfer arrangement by opening the poppet valve (9) in the check valve body (18), The problem of slackness in the opening of poppet valve (9) in the horizontal arrangement would results in the variation in the inlet air pressure. The poppet valve (9) face seats on the periphery of the check valve body (18) aid with conical spring force (10). When the hydraulic fluid enters in to the control valve body (1) from the master cylinder actuates hydraulic piston (4) and opens the poppet valve (9) through relay piston (8).
The movement of relay piston (8) through hydraulic pressure lifts the poppet valve (9), which Introduces air pressure into an air cylinder (6), and operates air piston (5). During hydraulic release force, relay piston attract towards the gravity and returns to home position faster due to return spring inline with decrease in hydraulic fluid pressure, there by poppet valve (9) shuts air inlet passage in the check valve body (18).

Fig 3 explains the arrangement made to suit for the installation in both planes. The bleed screw (13) position was designed at the top most point (Fig 4) in the assembly to avoid the air bubbles in the hydraulic fluid flow. The presence of air bubbles in the hydraulic fluid flow leads to poor clutch force performance would result in the loss of its primary function. Two bleed ports are positioned as shown in the fig 4. the port can be positioned to suit OEM vehicle installation condition opened according to our vehicle installation purpose.
The hydraulic fluid from the clutch master cylinder (Not illustrated) enters in to the control valve body (1) actuates the hydraulic piston (4) sliding in the hydraulic chamber(2) (Fig 2) portion in the control valve body (1 ) and it passes through the passage and actuates the relay piston(8) sliding in the air chamber(3) portion (Fig 2). These two portions are made as single cast results in the prevention of leak, ease of manufacturing and assembly etc.
The control valve body (1) is made as single cast where hydraulic actuation (Fig 2) and air transfer (Fig 2) are taking place. The single cast makes assembling easier and prevents hydraulic and air leak as against conventional clutch booster which has more number of joints/ components leads to fluid/air leak.
The check valve body (18) where the air enters from air reservoir is arranged in 90 degree from the assembly axis. It facilitates the installation of assembly becomes easier according to customer fitment requirement.

The bleeder screw (13) is positioned at the middle, facilitates the installation requirement of the customer thus the over all height is less which leads to fitment of clutch booster is more flexible. The overall height of clutch booster is 15 mm Approx less when compared to conventional clutch booster.
Air breather (12) is of compact design to suit in such a way to accommodate both wire mesh (15) (Diaphragm slits inside) and plate (16). Air Breather (12) is designed in such away that the foreign material will not enter into the assembly which leads to malfunction. The air breather (12) is designed as threaded type which eases assembling.
Air breather (12) is designed in such a way that the dust and any other foreign material will not enter in to the assembly else leads to performance malfunctioning. The construction of breather is explained as follows (Fig 5). The body of the breather arrangement is made of single mould (14) with a small projection at inside. This projection keeps the mesh to cover the six slots (17) provided in the body which is exposed to atmosphere. The mesh (15) made of nylon which would cover the slots and prevents the foreign materials to enter The washer (16) fixed in the insert keeps the mesh at its home position. Air breather (12) is also designed in such a way that the air breather assembly can be threaded in to the hole located in the control valve body(1).

WE CLAIM:
1, A clutch booster with a hydraulic drive member for an automobile having a clutch for engaging or disengaging transmission system from the engine of a vehicle in response to a force applied manually for operating the clutch on vehicle wherein the clutch booster is characterized vi/ith an air assisted hydraulic drive member comprising :
a. a clutch pedal operable manually
b. a master cylinder operable by the clutch pedal to generate pressurized
hydraulic fluid within and made available at hydraulic inlel port
c. a control valve body (1) operable by the master cylinder, the said
control valve body (1) characterized in having a single chamber
partitioned into a hydraulic chamber portion (2) having a Hydraulic
piston (4) and a air chamber portion (3) having relay piston (8) and a
passage disposed therein between the two chambers
d. a check valve body threaded on the control valve body
e. a slidably movable hydraulic piston (4) disposed in the hydraulic
chamber(2) and operable by pressurized hydraulic fluid from the
master cylinder through said inlet port B into a characterized sliding
motion thereby to slide a push rod (11) with a first forward force, which
push rod guided with the axial center part of the hydraulic piston(4).
f. a slidably movable relay piston (8) disposed in the air chamber portion
(3) of the control valve body (1)) operable by the hydraulic fluid from
the instance when the sliding push rod (11) meets the resistance, into a

characterized sliding motion of the relay piston(8) against gravity and adapted to reset w/ith gravity.
g. a poppet valve (9) disposed on the inner periphery of the check valve body (18) with a conical spring force (10) supported by gravitational force, the said poppet valve(9) operable by the sliding relay piston (8) sliding against gravity, the said poppet valve(9) characterized in its vertical arrangement and its vertical rise against gravity.
h. an air inlet A provided on the air chamber portion (3) of the control valve body(1) for allowing entry of air into the air cylinder through check valve body (18) from an air reservoir when the said poppet valve (9) is in open state, the said air inlet characterized in a vertical arrangement of the air inlet port A arranged in 90 degrees from the valve body axis,
i. a slidably movable air piston (5) disposed in the air cylinder (6) and operable by entry of pressurized air through a air transfer pipe (7) into the air cylinder (6) into a sliding motion of the air piston (5) thereby compounding the force on the push rod (11) with additional second forward force.
j. a bleed screw (13) disposed on the control valve body(1) at a topmost point of the hydraulic fluid flow in the control valve body (1) and selectively with one of the three bleed ports arranged on the control valve body(1), characterized further in its positioning in between the hydraulic chamber(2) and the air chamber(3).
k. an air breath8r(12) disposed on the main control valve body (1) a portion characterized in having atleast two filters including wire mesh

filter (15) and a diaphragm plate type filter (16) and which is generally a plug threaded type in control valve body (1).
2. The said breather (12) as claimed in claim 1 is single mould (14) with a small projection made within, said projection holding a steel mesh with a washer (16) fixed in an insert to cover a set of slots (17) provided on the air breather (12) single mould (14) which is exposed to atmosphere.
3. The said breather (12) as claimed in claim 2 is further adapted to be threaded into a hole formed on the control valve body{1).
4. The push rod as claimed in claim 1 is characterized in having the first end
guided on the hydraulic piston(4) and a opposite second end attached on to
the clutch lever and being reciprocally movable for engaging or disengaging
the clutch from the engine of the automobile.