JP4269737B2 - Clutch booster - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a clutch booster for increasing the depressing force of a clutch pedal of an automobile and transmitting it to a clutch mechanism.
[0002]
[Prior art]
A clutch booster, a so-called clutch booster, is used to reduce the depression force of a clutch pedal of an automobile. A general clutch booster includes a cylinder that houses a hydraulic piston that is driven by hydraulic pressure generated when a clutch pedal is depressed, a relay valve that opens a flow of compressed air by the hydraulic pressure, A power piston housed inside and a force transmission member for transmitting the movement of the power piston to the hydraulic piston are provided.
[0003]
The inside of the shell is partitioned into a pressure chamber and an atmospheric chamber by the power piston. When the clutch pedal is stepped on, the hydraulic piston is driven and the relay valve is opened to supply compressed air to the pressure chamber. When the power piston is driven by the compressed air supplied to the pressure chamber, a force in the same direction as the hydraulic piston, that is, a catching force in the direction of disengaging the clutch is generated.
[0004]
As the engine output increases, the clutch operating force tends to increase. For this reason, a larger catching power is desired. The auxiliary force depends on the size of the pressure receiving area of the power piston. That is, as the pressure receiving area of the power piston is larger, a larger assist force is generated. Therefore, a tandem clutch booster in which two power pistons are arranged in series has also been proposed. (For example, see Patent Document 1 below)
The clutch booster described in Patent Document 1 includes a first power piston in which a first shell and a second shell are arranged in series in the axial direction of a cylinder in which a hydraulic piston is accommodated, and is accommodated in the first shell. Thus, the inside of the first shell is partitioned into a first pressure chamber and a first atmospheric chamber. Moreover, the inside of the second shell is partitioned into a second pressure chamber and a second atmospheric chamber by the second power piston accommodated in the second shell.
[0005]
The relay valve and the first pressure chamber are connected to each other by an air pipe, and compressed air sent from a compressed air supply source is supplied to the first pressure chamber via the relay valve. The second pressure chamber communicates with the first pressure chamber via an air passage formed in the shaft portion of the first power piston.
[0006]
[Patent Document 1]
Japanese Patent Laid-Open No. 11-108079
[Problems to be solved by the invention]
In the clutch booster of Patent Document 1, since the first and second shells are arranged in series in the axial direction of the cylinder, the entire length of the entire apparatus including the cylinder and the first and second shells is considerably increased. There is a problem that it ends up.
[0008]
In the clutch booster disclosed in Patent Document 1, the compressed air sent from the relay valve is first supplied to the first pressure chamber, and the compressed air in the first pressure chamber is supplied to the second pressure while the first power piston is pushed. By entering the room, the second power piston is driven. For this reason, a time lag occurs in the force pushing the first power piston and the second power piston, and there is a problem in the responsiveness of the second power piston.
[0009]
Accordingly, an object of the present invention is to provide a tandem type clutch booster capable of shortening the overall length. More preferably, it is to provide a clutch booster capable of improving the response of the power piston.
[0010]
[Means for Solving the Problems]
The present invention includes a cylinder housing a hydraulic piston driven by a hydraulic pressure generated when a clutch pedal is depressed, a rod member that moves integrally with the hydraulic piston in the axial direction of the cylinder, and the hydraulic pressure. A relay valve that opens a compressed air flow part when received, a first shell part and a second shell part arranged in series in the axial direction of the cylinder, and the first shell housed in the first shell part A first power piston that divides the interior of the portion into a first pressure chamber and a first atmospheric chamber, and is housed in the second shell portion and divides the interior of the second shell portion into a second pressure chamber and a second atmospheric chamber. A clutch booster comprising: a second power piston; and an air flow path for supplying compressed air sent from a compressed air supply source to the first and second pressure chambers through the flow part of the relay valve. The Wherein the first shell portion is formed on the rear side of the axial direction of the cylinder, the second shell portion is formed in the cylinder concentric to surround the outer periphery of the cylinder, the outer peripheral surface of the second power piston the cylinder And a first force transmission member that is housed between the first shell and the inner peripheral surface of the second shell portion, and transmits the axial movement of the first power piston to the hydraulic piston, and the second power piston. A second force transmission member that transmits axial movement to the rod member, and a front end portion of the first force transmission member is connected to the hydraulic piston and a rear end of the first force transmission member Is provided on the first power piston, a rear end portion of the second force transmission member is fixed to the second power piston, and a front end portion of the second force transmission member is a locking portion of the rod member. It is locked to .
[0011]
In the clutch booster of the present invention configured as described above, the hydraulic piston is driven by the hydraulic pressure generated when the clutch pedal is depressed, and the relay valve is operated by the hydraulic pressure. For this reason, the compressed air sent from the compressed air supply source is simultaneously supplied to the first and second pressure chambers via the air flow path. The first and second power pistons are driven by the compressed air supplied to the first and second pressure chambers, and the movement of these power pistons is applied to the rod member via the force transmission member.
[0012]
In a preferred embodiment of the present invention, the air flow path includes a first air pipe connected to the first pressure chamber and a second air pipe connected to the second pressure chamber. The two air pipes branch in two on the downstream side of the flow part of the relay valve so that the compressed air is supplied to the first and second pressure chambers at the same time. Are connected in parallel.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.
A clutch booster 10 shown in FIG. 1 is applied to a clutch mechanism 11 of an automobile equipped with a manual transmission. The clutch booster 10 is provided between a clutch mechanism 11 and a hydraulic pressure generator 13 that is linked to a clutch pedal 12. The hydraulic pressure generator 13 is configured to generate hydraulic pressure when the driver steps on the clutch pedal 12.
[0014]
The clutch mechanism 11 includes a pressure plate 20, a facing 21, a disk plate 22, a spring 23, a release bearing 24, a release lever 25, a link 26 and the like, as in the conventional case.
[0015]
The clutch booster 10 includes a cylinder 31 having a hydraulic chamber 30, a hydraulic piston 32 accommodated in the cylinder 31, a relay valve 34 connected to a compressed air supply source 33, and an axial direction of the cylinder 31. The first shell part 35 and the second shell part 36 arranged in series, the first power piston 37 accommodated in the first shell part 35, the second power piston 38 accommodated in the second shell part 36, etc. I have.
[0016]
The hydraulic chamber 30 is defined by the end face of the hydraulic piston 32, the front wall 39 of the first shell portion 35, the rear wall 40 of the second shell portion 36, and the like. The hydraulic chamber 30 is connected to the hydraulic pressure generator 13 via a hydraulic pipe 45.
[0017]
The hydraulic piston 32 can reciprocate in the axial direction of the cylinder 31. A rear end 50 a of the rod member 50 is connected to the hydraulic piston 32. The rod member 50 moves in the axial direction of the cylinder 31 integrally with the hydraulic piston 32. The front end 50 b of the rod member 50 is connected to the link 26 of the clutch mechanism 11.
[0018]
For this reason, when the clutch pedal 12 is depressed, the hydraulic fluid pressurized by the hydraulic pressure generator 13 is supplied to the hydraulic pressure chamber 30, and the hydraulic piston 32 is driven in the direction indicated by the arrow A in FIG.
[0019]
The relay valve 34 includes a pressure receiving part 55 that receives the pressure of the hydraulic pressure chamber 30, an air circulation part 56, a valve body 57 that opens and closes the air circulation part 56, and the like. The valve body 57 is biased by a spring 58 in a direction to close the air circulation portion 56. When the clutch pedal 12 is depressed and pressurized hydraulic fluid is supplied to the hydraulic pressure chamber 30, the valve body 57 moves in a direction to open the air circulation portion 56.
[0020]
The first shell portion 35 and the second shell portion 36 are arranged in series along the axial direction of the cylinder 31 (the direction in which the hydraulic piston 32 moves). The inside of the first shell portion 35 is partitioned into a first pressure chamber 61 and a first atmospheric chamber 62 by a first power piston 37.
[0021]
The inside of the second shell portion 36 is partitioned into a second pressure chamber 63 and a second atmospheric chamber 64 by a second power piston 38. Air release holes 65 and 66 communicating with the atmospheric chambers 62 and 64 are formed in the shell portions 35 and 36.
[0022]
The second shell portion 36 is formed concentrically with the cylinder 31 outside the cylinder 31 so as to surround the outer periphery of the cylinder 31. The second power piston 38 is accommodated between the outer peripheral surface of the cylinder 31 and the inner peripheral surface of the second shell portion 36. For this reason, the second power piston 38 is formed in an annular shape (ring shape) when viewed from the direction of arrow B in FIG.
[0023]
A force transmission member 70 is provided inside the first shell portion 35. The force transmission member 70 passes through the front wall 39 of the first shell portion 35 and extends in the axial direction of the cylinder 31. The force transmission member 70 also serves as a shaft portion of the first power piston 37.
[0024]
A front end portion 70 a of the force transmission member 70 is connected to the hydraulic piston 32, and the movement of the first power piston 37 in the axial direction can be transmitted to the hydraulic piston 32. The rear end portion 70 b of the force transmission member 70 can be brought into contact with the rear end wall 72 of the first shell portion 35 that functions as a stopper of the first power piston 37.
[0025]
The second shell portion 36 is provided with a force transmission member 73 for transmitting the movement of the second power piston 38 in the axial direction to the rod member 50. The force transmission member 73 has a cylindrical shape, the rear end portion 73 a is fixed to the second power piston 38, and the front end portion 73 b is engaged with the locking portion 74 of the rod member 50.
[0026]
Return springs 75 and 76 are accommodated in the first and second shell portions 35 and 36, respectively. The return springs 75 and 76 urge the power pistons 37 and 38, that is, the power pistons 37 and 38 in a direction indicated by an arrow B in FIG.
[0027]
A first air pipe 81 and a second air pipe 82 that function as an air flow path are disposed outside the shell portions 35 and 36. One end of the first air pipe 81 communicates with the air circulation part 56 of the relay valve 34. The other end of the first air pipe 81 is connected to the air circulation hole 83 of the first pressure chamber 61.
[0028]
One end of the second air pipe 82 communicates with the air circulation part 56 of the relay valve 34. The other end of the second air pipe 82 is connected to the air circulation hole 84 of the second pressure chamber 63.
[0029]
That is, the first and second air pipes 81 and 82 branch in two directions on the downstream side of the flow part 56 of the relay valve 34 with respect to the flow direction of the compressed air. Connected in parallel.
[0030]
For this reason, when the valve element 57 of the relay valve 34 is opened, the compressed air sent from the compressed air supply source 33 is connected to the first pressure chamber 61 and the second pressure via the first air pipe 81 and the second air pipe 82. It will be supplied to the chamber 63 simultaneously.
[0031]
The operation of the clutch booster 10 will be described below.
When the clutch pedal 12 is stepped on as shown by an arrow P in FIG. 2, the hydraulic fluid pressurized by the hydraulic pressure generator 13 is supplied to the hydraulic chamber 30 via the hydraulic pipe 45.
[0032]
When pressurized hydraulic fluid is supplied to the hydraulic chamber 30, the hydraulic piston 32 moves in the direction indicated by arrow A in FIG. 2 and the valve element 57 of the relay valve 34 opens the air circulation portion 56. Move in the direction.
[0033]
Thereby, the compressed air sent from the compressed air supply source 33 is sent simultaneously to the first air pipe 81 and the second air pipe 82 via the air circulation part 56. As shown by arrows C 1 and C 2 in FIG. 2, the compressed air passing through the first air pipe 81 is directly supplied to the first pressure chamber 61, and the compressed air passing through the second air pipe 82 is supplied directly to the second pressure chamber 63. Is done.
[0034]
By supplying compressed air to the first pressure chamber 61 and the second pressure chamber 63, the first power piston 37 and the second power piston 38 are driven simultaneously. That is, the force in the direction of arrow A applied to the first power piston 37 is applied to the hydraulic piston 32 via the force transmission member 70, and the force in the direction of arrow A applied to the second power piston 38 is transmitted via the force transmission member 73. To the rod member 50.
[0035]
When the rod member 50 moves in the direction of arrow A, the release bearing 24 is pushed through the link 26, and the pressure plate 20 moves in a direction away from the disk plate 22 (direction in which the clutch is disengaged).
[0036]
When the clutch pedal 12 is released, the hydraulic pressure of the hydraulic pressure generator 13 decreases and the pressure of the hydraulic chamber 30 decreases, and the hydraulic piston 32 moves in the direction of arrow B (shown in FIG. 1). For this reason, the pressure plate 20 presses the facing 21 by the spring 23 of the clutch mechanism 11, and the clutch is connected. Further, the air circulation portion 56 is closed by closing the valve body 57 of the relay valve 34.
[0037]
Further, the first and second power pistons 37 and 38 are moved in the direction of arrow B by the return springs 75 and 76. When the first and second power pistons 37 and 38 move in the direction of arrow B, the air in the pressure chambers 61 and 63 passes through the air pipes 81 and 82 to the atmosphere from the air discharge port (not shown) of the relay valve 34. Released.
[0038]
In the clutch booster 10 of this embodiment, the second shell portion 36, the second power piston 38, and the force transmission member 73 are concentrically disposed on the outer peripheral side of the cylinder 31. Therefore, the overall length L (shown in FIG. 1) of the entire device including the cylinder 31 and the first and second shell portions 35 and 36 is compared with a conventional tandem clutch booster (for example, Patent Document 1). Can be shortened.
[0039]
Further, according to the clutch booster 10 of this embodiment, when the clutch pedal 12 is depressed, the compressed air passing through the air circulation portion 56 of the relay valve 34 is supplied to the first pressure chamber 61 and the second pressure chamber 63. Are supplied at the same time. For this reason, the auxiliary force by the first power piston 37 and the second power piston 38 is simultaneously applied to the rod member 50.
[0040]
For this reason, the responsiveness of the tandem clutch booster 10 having the two power pistons 37 and 38 is improved, and a desired boosting function can be exhibited from the initial depression of the clutch pedal 12.
[0041]
Further, since both the first air pipe 81 and the second air pipe 82 are provided outside the shell portions 35 and 36, the shaft of the power piston as in the clutch booster described in Patent Document 1 above. It is not necessary to form an air passage in the part, the structure is simple, and processing is easy.
[0042]
【The invention's effect】
According to the first aspect of the present invention, in the tandem clutch booster having the first and second shell portions, the overall length of the device including the cylinder and the shell portion can be reduced.
[0043]
According to the second aspect of the present invention, the first power piston and the second power piston can operate with good responsiveness and exert auxiliary force.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view schematically showing a clutch booster and a clutch mechanism according to an embodiment of the present invention.
FIG. 2 is a cross-sectional view of the clutch booster shown in FIG. 1 during operation.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Clutch booster 11 ... Clutch mechanism 12 ... Clutch pedal 30 ... Hydraulic pressure chamber 31 ... Cylinder 32 ... Hydraulic pressure piston 33 ... Compressed air supply source 34 ... Relay valve 35 ... First shell part 36 ... Second shell part 37 ... 1st power piston 38 ... 2nd power piston 50 ... Rod member 56 ... Flowing part 61 ... 1st pressure chamber 62 ... 1st atmospheric chamber 63 ... 2nd pressure chamber 64 ... 2nd atmospheric chamber 70, 73 ... Force transmission member 81 ... 1st air piping (air flow path)
82 ... Second air piping (air flow path)

Claims (2)

A cylinder containing a hydraulic piston driven by the hydraulic pressure generated when the clutch pedal is depressed;
A rod member that moves integrally with the hydraulic piston in the axial direction of the cylinder;
A relay valve that opens a flow of compressed air when subjected to the fluid pressure; and
A first shell portion and a second shell portion arranged in series with each other in the axial direction of the cylinder;
A first power piston housed in the first shell portion and partitioning the interior of the first shell portion into a first pressure chamber and a first atmospheric chamber;
A second power piston housed in the second shell portion and partitioning the inside of the second shell portion into a second pressure chamber and a second atmospheric chamber;
An air flow path for supplying compressed air sent from a compressed air supply source to the first and second pressure chambers through the flow part of the relay valve;
A clutch booster comprising:
The first shell portion is formed on the rear side in the axial direction of the cylinder;
The second shell portion is formed concentrically with the cylinder so as to surround an outer periphery of the cylinder;
The second power piston is accommodated between an outer peripheral surface of the cylinder and an inner peripheral surface of the second shell portion; and
A first force transmission member for transmitting the axial movement of the first power piston to the hydraulic piston;
A second force transmission member that transmits the axial movement of the second power piston to the rod member;
A front end portion of the first force transmission member is connected to the hydraulic piston, and a rear end portion of the first force transmission member is provided to the first power piston;
The rear end portion of the second force transmission member is fixed to the second power piston, and the front end portion of the second force transmission member is locked to the locking portion of the rod member. Clutch booster. The air flow path is
A first air pipe connected to the first pressure chamber;
A second air pipe connected to the second pressure chamber,
These first and second air pipes are
The compressed air is bifurcated on the downstream side of the flow part of the relay valve so that the compressed air is simultaneously supplied to the first and second pressure chambers, and each is connected in parallel to the first and second pressure chambers. The clutch booster according to claim 1, wherein

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