JPH09269021A - Automatic clutch device for automobile - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate unbalance of amount of operation oil in automatic and manual operation oil supply mechanisms from an automobile automatic clutch device capable of manual operation, prevent abrupt starting at the changeover time from automatic to manual operation, and keep the amount of operation oil constant irrespective of abrasion of a clutch while feeding the residual operation oil in the slave cylinder back to an oil tank only through the operation of a clutch pedal. SOLUTION: A changeover cylinder 40 has a changer in which arranged are a first piston 43 pressurized between a manual operation oil passage 9 and an automatic operation oil passage 16 by means of a spring 42 and a second piston 42 pressurized by means of a spring 45 therebetween, and whose capacity is equalized to that of a master cylinder pedal-full stroke. An operation oil pipe 23 is connected to the second piston on the side of the spring 45. A pipe passage 36 from a relief valve 18 is connected across the pistons. A port 50 is formed on the changeover cylinder on the side of the spring 45, and communicated with an oil tank 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of an automatic clutch device for an automobile which can be operated manually.

[0002]

2. Description of the Related Art An automatic transmission that electronically shifts a transmission electronically according to operating conditions such as engine speed, accelerator opening, vehicle speed, etc., and also controls a vehicle by automatically connecting and disconnecting a mechanical friction clutch. In such an automatic transmission, an automatic transmission for a vehicle in which the mechanical friction clutch can be manually operated is known from, for example, Japanese Utility Model Publication No. 4-8023. That is, the automatic transmission described in the above publication is suitable for starting under special conditions such as starting over obstacles, starting up a steep slope, starting up on a snowy road, etc. such that the friction clutch cannot be connected or disconnected and the vehicle cannot start. Under these special conditions, the automatic clutch control is stopped so that the clutch can be engaged and disengaged by manual operation.This is output to the control system of the automatic transmission during gear shifting. Means for shutting off the clutch actuation signal when the clutch pedal is depressed, a control valve that responds to the clutch pedal and supplies the working fluid to the clutch booster (actuator such as slave cylinder), and selects the working fluid to the booster. It is equipped with a double check valve that feeds the material.

On the other hand, the transmission is manually operated, and only the clutch is basically automatically (automatically) connected / disconnected in accordance with the speed change state and the operating state, which is determined by the driver or automatically. An automatic clutch device as shown in FIG. 2 has been put into practical use, which enables a manual operation when the operation is impossible. That is, this device
A slave cylinder 4 connected to the upper end of a clutch release fork 3 which rotates about a as a fulcrum and whose lower end pushes the release bearing 2 of the friction clutch 1 and a clutch pedal 5.
Booster mechanism 6 and oil tank 7 that operate by stepping on
A master cylinder 8 and a hydraulic fluid pipe 9 connected to the cylinder 8 for manual operation, and an oil tank 11 and a pipeline 12.
A gear pump 14 driven by a motor 13 and a hydraulic oil line 1 connected to the gear pump 14 via a check valve 15.
6, a relief valve 18 provided in a pipe line 17 extending from between the gear pump 14 and the check valve 15 to the oil tank 11.
And a hydraulic oil supply mechanism 21 for automatic operation, which comprises an electromagnetic valve 20 provided in a return pipeline 19 from the hydraulic fluid pipeline 16 to the oil tank 11, and a switching mechanism for switching between the hydraulic fluid pipelines 9 and 16. It is connected to the slave cylinder 4 via 22 by a pipe line 23. As the switching mechanism 22, for example, an electromagnetic switching valve 22 'as shown in FIG. 3 is used, and the hydraulic oil conduit 9 of the manual operation hydraulic oil supply mechanism 10 and the automatic operation hydraulic oil supply mechanism 2 are used.
The hydraulic fluid pipe 16 of No. 1 is switched and connected to the slave cylinder 4.

With the above structure, when the operation of the friction clutch 1 is switched from manual operation to automatic operation, for example, the switching mechanism 22 (electromagnetic switching valve 22 ') is manually or automatically switched to the automatic side and the motor is operated. When the gear pump 14 is driven by 13, the hydraulic fluid opens the check valve 15 and enters the slave cylinder 4 in the pipeline 23 through the hydraulic fluid pipeline 16 and the switching mechanism 22 (electromagnetic switching valve 22 '), causing the piston 4a to move. , The clutch release fork 3 is rotated clockwise about the fulcrum a, and the release bearing 2 is pushed to the left to disconnect the friction clutch 1. When the position sensor (not shown) provided in the slave cylinder 4 detects that the piston 4a has moved by a predetermined stroke, the motor 13
To stop the rotation of the pump 14. After turning off the power to the motor 13 and stopping the gear pump 14,
When the solenoid valve 20 is opened while controlling the return speed of the hydraulic oil, the hydraulic oil in the slave cylinder 4 is supplied to the piston 4a via the release bearing 2 and the clutch release fork 3 by the spring in the friction clutch 1. By the return of the above, the oil is returned from the pipe 23 and the hydraulic oil pipe 16 to the oil tank 11 via the return pipe 19 and the solenoid valve 20. As a result, the friction clutch 1 becomes "contact".

Similarly, when the switching mechanism 22 is manually or automatically switched to, for example, the manual mode, the switching mechanism 22, that is, the electromagnetic switching valve 22 'is switched to the manual side as shown in FIG. If you step on,
The booster mechanism 6 operates and the piston 8 in the master cylinder 8
2 is moved to the left in FIG. 2 so that the working oil is passed through the working oil conduit 9 and the switching mechanism 22 (electromagnetic switching valve 22 ') to the conduit 2
3, the piston 4a is pushed to the right in FIG. 2, and the clutch release fork 3 is rotated clockwise around the fulcrum a, and the release bearing 2 is pushed to the left to disengage the friction clutch 1. "No". When the clutch pedal 5 is returned, the piston 8a in the master cylinder 8 returns to the right in FIG. 3 by the spring in the cylinder 8 and the booster mechanism 6, and at the same time, the release bearing 2 and the clutch by the spring in the friction clutch 1 are released. Due to the return of the piston 4a via the release fork 3, the hydraulic oil in the slave cylinder 4 is transferred to the pipe line 23.
And it returns via the hydraulic oil pipe line 9 and returns to the oil tank 7 via the master cylinder 8. As a result, the friction clutch 1 becomes "contact".

By the way, it has been found that the one operated by hydraulic oil as shown in FIG. 2 has the following problems when the electromagnetic switching valve 22 'as shown in FIG. 3 is used as the switching mechanism. (1) Imbalance of the amount of hydraulic oil in both hydraulic oil supply mechanisms When the friction clutch 1 is in the "contact" state, that is, the piston 4a of the slave cylinder 4 is at the left end in FIG. When there is no hydraulic oil in the slave cylinder 4, the hydraulic oil does not move between the hydraulic oil supply mechanisms 10 and 21 and no trouble occurs, but when the clutch 1 is "disengaged", that is, the slave cylinder When the piston 4a of the cylinder 4 is at the position shown in FIG. 2 or at the right of FIG. 2 and the switching is performed when the slave cylinder 4 is filled with hydraulic oil, the operation between the hydraulic oil supply mechanisms 10 and 21 is performed. Oil flows back and forth, one of the two oil tanks 7 and 11 overflows, and the other becomes empty.

For example, after depressing the clutch pedal 5 to disengage the friction clutch 1 (at this time, the slave cylinder 4 is filled with hydraulic oil from the oil tank 7), the electromagnetic switching valve 22 'is automatically turned on. When switched, the pipe line 23 connected to the slave cylinder 4 is disconnected from the hydraulic oil pipe line 9 connected to the oil tank 7, and is connected to the return pipe line 19 of the automatic operation hydraulic oil supply mechanism 21. Therefore, in this state, when the solenoid valve 20 is opened as described above, the hydraulic oil in the slave cylinder 4 flows into the oil tank 11 through the return pipe 19 and the friction clutch 1 becomes "contact". This phenomenon means that the hydraulic oil in the oil tank 7 has been returned to the oil tank 11, and if the above operation is repeated many times, the oil tank 7 becomes empty as described above and the oil An event may occur in which the hydraulic oil overflows from the tank 11.

(2) Rapid start for automobile when switching from automatic operation to manual operation Similarly to the above, there is no problem when switching from automatic operation to manual operation is performed when the friction clutch 1 is in the "contact" state. When the clutch 1 is switched to the manual operation by the automatic operation after the clutch 1 is disengaged, the master cylinder 8 and the oil tank 7 are in communication with each other when the clutch pedal 5 is not stepped on. The hydraulic oil in the slave cylinder 4 is supplied to the pipeline 23, the electromagnetic switching valve 2
2 ′ and the hydraulic oil line 9 are all returned to the oil tank 7, and as a result, the friction clutch 1 suddenly becomes “contact”, and if the gear of the transmission is engaged at this time, the vehicle may suddenly start. is there.

Although various measures can be taken to prevent the occurrence of the above situation, modification of the master cylinder 8 is difficult because it is difficult to deal with air bleeding, wear of the clutch, high cost, and the like. It is difficult to integrate the oil tanks 7 and 11 in the oil supply mechanisms 10 and 21 due to the positional restrictions of both. In consideration of the above points and backup in case of a failure of the electronic system, a malfunction occurs when the automatic operation is changed to the manual operation with the clutch "disengaged", that is, the slave cylinder 4 is filled with hydraulic oil and the clutch In order to solve the problem that the pedal 5 cannot be depressed and the slave cylinder 4 may be damaged due to excessive depression of the clutch pedal 5, an automobile automatic clutch device as shown in FIG. 4 is considered.

The one shown in FIG. 4 is provided with a slave cylinder 4 for connecting / disconnecting the friction clutch 1, with respect to the cylinder 4.
In the automatic clutch device for an automobile, the automatic operation hydraulic oil supply mechanism 21 operated by the pump 14 and the manual operation hydraulic oil supply mechanism 10 operated by the clutch pedal 5 are configured to be selectively pipe-connectable to each other. A hydraulic fluid line 9 of the operating hydraulic fluid supply mechanism 10,
A cylinder 31 is provided between the automatic operation hydraulic oil supply mechanism 21 and the hydraulic oil pipes 23 of the slave cylinder 4.
A switching cylinder 30 having a piston 33 biased by a spring 32 is disposed on one side, and the manual operation hydraulic oil supply mechanism 10 is provided on the piston 33 side of the cylinder 30.
The hydraulic oil pipe 9 is connected to the automatic operation hydraulic oil supply mechanism 21 and both hydraulic oil pipelines 23 of the slave cylinders 4 on the spring 32 side, and the automatic operation hydraulic oil supply mechanism 21 is provided. The pump pressure adjusting relief valve 18 is connected by a pipe 34 between the hydraulic oil pipe 16 of the automatic operation hydraulic oil supply mechanism and the oil tank 11, and a stopper 35 for restricting the stroke of the cylinder is attached to the slave cylinder 4. It is arranged. FIG.
2 which are the same as those in FIG. 2 represent the same members.

With such a structure, in the automobile auto clutch device of FIG. 4, the operation of the friction clutch 1 is performed as follows.
For example, when switching from manual operation to automatic operation, the motor 13 is manually or automatically turned on and the gear pump 14 is driven by the motor 13, so that the working oil opens the check valve 15 and the working oil pipe line 16 and the pipe line. At 23, it is sent directly to the slave cylinder 4. Therefore, the piston 4
4 is pushed to the right in FIG. 4, whereby the friction clutch is “disengaged” via the clutch release fork and the release bearing in the same manner as described above. However, when the slave cylinder 4 is filled with hydraulic oil, as described above, When the automatic operation is switched to the manual operation, if the clutch pedal 5 is strongly stepped on the relief valve 18 so as to generate a hydraulic pressure higher than the set pressure, the piston 8a in the master cylinder 8 is moved leftward in FIG. , Hydraulic oil is hydraulic oil line 9
Then, it is press-fitted into the cylinder 31 from one side 31a of the cylinder 31 of the switching cylinder 30.

As a result, the piston 33 is moved to the cylinder 3
1 to the left against the spring 32 and to the cylinder 3 of FIG.
The hydraulic oil on the side of the spring 32 of No. 1 enters the pipeline 34 through one of the hydraulic fluid pipeline 16 and the return pipeline 19 and opens the relief valve 18 disposed in the pipeline 34 to open the relief pipeline 18 from the other side of the return pipeline 19. Escape to tank 11. If the clutch pedal 5 is returned from this state, the friction clutch becomes "contact" by the amount of the hydraulic oil returned to the oil tank 11, and manual operation becomes possible. When the clutch pedal 5 is strongly depressed, the working oil is further transferred to the slave cylinder 4 via the working oil line 23.
Although the piston 4a tries to move further in the clutch "disengaged" direction by being press-fitted into the cylinder, the stopper 35 restricts the stroke of the piston 4a to avoid increase in hydraulic oil in the slave cylinder 4 and damage to the cylinder.

By the way, the distance between the stopper 35 and the release fork 3 in FIG. 4 increases due to abrasion of the sliding portion of the friction clutch 1, for example, the clutch driven plate 1a, and the clutch 1 is "disengaged" by automatic operation. If you switch to manual operation with
Even when stepping on, the piston 4a of the slave cylinder 4 actually moves to the stopper 35, and only the hydraulic oil in the master cylinder 8 that is stepped on after contacting the stopper 35 is the hydraulic oil line 16 as described above. And the return line 19 to enter the line 34, the relief valve 18 disposed in the line 34 is opened, and the other side of the return line 19 escapes to the tank 11. Pedal 5
When stepping on, the amount of hydraulic oil that escapes to the tank 11 decreases, the "disengagement" and "contact" positions of the clutch change, and the driving feeling changes. Therefore, it is necessary to move the stopper 35 to the slave cylinder 4 side by the wear amount. However, since the wear amount cannot be accurately grasped in reality, this adjustment is very difficult and time-consuming. However, if the adjustment is neglected, the gap between the stopper 35 and the release fork 3 becomes wider and disturbs the driving feeling, and the adjustment is bad and the adjustment amount is smaller than the normal value, for example, when it is set to zero. However, even if the clutch pedal 5 is released in this state, a situation may occur in which the clutch does not return to the "contact" position, and it becomes impossible to manually drive the vehicle.

[0014]

SUMMARY OF THE INVENTION Therefore, the problem to be solved by the present invention is to eliminate the imbalance in the amount of hydraulic oil in both the automatic and manual hydraulic oil supply mechanisms in an auto clutch device for automobiles which can also be operated manually. , It has the function of preventing the sudden start of the automobile when switching from automatic operation to manual operation, and returning the hydraulic oil that accumulates in the slave cylinder to the oil tank by a simple operation of the clutch pedal at the same time. It is an object of the present invention to provide an automobile automatic clutch device in which the amount of hydraulic oil fed to the engine is kept constant regardless of the wear of the clutch, and the stopper for preventing the failure of the slave cylinder due to the excessive depression of the clutch pedal is eliminated.

[0015]

SUMMARY OF THE INVENTION To solve the above-mentioned problems, an automobile auto-clutch device of the present invention comprises a slave cylinder for connecting and disconnecting a friction clutch, and a hydraulic pump for automatic operation is supplied to the cylinder by a pump. An automatic clutch device for an automobile configured to selectively pipe-connect a mechanism and a manual operation hydraulic oil supply mechanism operated by a clutch pedal, wherein the hydraulic oil conduit of the manual operation hydraulic oil supply mechanism and the automatic A first piston, which is pressed by a spring to one end side of the cylinder when not in operation, between the operation hydraulic oil supply mechanism and both hydraulic oil pipes of the slave cylinder, and the same piston direction while maintaining a distance from the first piston. A switching cylinder having a second piston biased by a spring is provided, and the manual cylinder is provided on the first piston side of the cylinder. Of the slave cylinder, the hydraulic oil pipeline of the slave cylinder is connected to the biasing spring side of the second piston, and the hydraulic fluid supply mechanism for automatic operation is connected between the pistons. Between the hydraulic oil pipeline and the pipeline to the relief valve for pump pressure adjustment provided in the supply mechanism, and the second piston is not installed in the chamber provided with the second piston spring of the cylinder. It is characterized by forming a port that communicates with the oil tank during operation.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described in detail with reference to FIG. Note that, in FIG. 1, the same reference numerals as those in FIGS. 2 and 4 denote the same members, and description thereof will be omitted. A switching cylinder 40 includes a first piston 43, which is biased by a spring 42 to one side 41a of the cylinder 41, in the cylinder 41,
A second piston 46, which is biased by a spring 45 so as to come into contact with a stopper 44 formed in the center of the cylinder 41, is internally provided, and similarly to the above, the first piston 43 is convex toward the side facing the one side 41a. Even when the portion 43a is formed and is pressed against the one side 41a of the cylinder 41 by the spring 42 when not in operation, a gap for facilitating the pressing of the piston 43 is provided between the one side 41a and the first piston 43. So that it can be formed.

The pipe for the switching cylinder 40 is connected to the first piston 43 side of the cylinder 41, that is, the one side 4 thereof.
1a in the first chamber 47, the hydraulic oil line 9 of the master cylinder 8
The second spring on the side of the biasing spring 45 of the second piston 46.
Both working oil pipe lines 23 of the slave cylinder are connected to the chamber 48, and the third chamber 49 between the pistons 43 and 46 is connected as follows. That is, the third chamber 4
On one side, the hydraulic oil conduit 16 of the automatic operation hydraulic oil supply mechanism 21 is provided, and on the other side of the third chamber 49, a half clutch arranged in parallel with the return conduit 19 of the supply mechanism 21. The upstream sides of the electromagnetic valves 20 and 20 'and the relief valve 18 for transmission and shifting are respectively connected by the pipeline 36. Further, the second chamber 48 is provided with a port 50 that opens when the second piston 46 is not in operation, that is, in a state of being in contact with the stopper 44, and the port 50 is connected to the oil tank 1 by a pipe line 51.
Connected to 1. The capacity of the second chamber 48 when the second piston 46 is not operated is equal to the capacity of the master cylinder 8 in the manual operation hydraulic oil supply mechanism when the pedal is fully stroked.

In the automobile automatic clutch device of FIG. 1 configured as described above, the operation of the friction clutch 1 is
For example, when switching from manual operation to automatic operation, if the motor 13 is turned on manually or automatically and the gear pump 14 is driven by the motor 13, the hydraulic oil opens the check valve 15 and switches through the hydraulic oil conduit 16. Cylinder 4
It is press-fitted into the third chamber 49 of the cylinder 41 of No. 0 and pushes both the pistons 43 and 46. As a result, the second piston 46 moves to the right in FIG. 1 against the spring 45, and the second chamber 48
The hydraulic oil therein is press-fitted into the slave cylinder 4 through the pipe line 23, and the clutch is "disengaged". At this time, since the volume of the second chamber 48 is equal to the capacity of the master cylinder 8 at the time of pedal full stroke, the amount of hydraulic oil supplied to the slave cylinder 4 is always regulated to the capacity of the master cylinder 8 at pedal full stroke.

If the clutch pedal 5 is depressed in this state and the clutch pedal 5 is depressed, hydraulic oil enters the first chamber 47 of the switching cylinder 40 from the master cylinder 8 via the hydraulic oil pipe 9, and the solenoid valve 20, Since 20 'is closed, the distance between the first piston 43 and the second piston 46 does not change, and the second piston 46 remains in the cylinder 4 as it is.
Move to the right end of No. 1 and after the corresponding contact, move to the third chamber 49
The internal pressure rises and the hydraulic oil in the chamber 49 escapes to the oil tank 11 by opening the relief valve 18 from the pipe line 36 through the line 34 as the first piston 43 moves to the right.
If the clutch pedal 5 is released here, the piston 4a returns to the spring of the clutch and the slave cylinder, whereby the friction clutch 1 becomes "contact" and the switching cylinder 4
The first and second pistons 43,
46 returns to the position shown in FIG. 1, and manual operation becomes possible.

The driven plate 1 of the friction clutch 1
When a is worn, the piston 4 of the slave cylinder 4
Although a is further moved to the left in FIG. 1 by the amount corresponding to the wear amount in addition to the regular movement amount, the second piston 46 is restricted from moving to the left by the stopper 44, so that the wear is reduced. The hydraulic oil equivalent to the amount is the second oil of the switching cylinder 40 which is opened when the friction clutch is in the “contact” state.
Returning from the port 50 of the chamber 48 to the oil tank 11 via the line 51. That is, when the friction clutch is completely "contacted", the second piston 46 is always in contact with the stopper 44, and the amount of oil for disconnecting the clutch is constant regardless of the amount of wear of the clutch.

[0021]

Industrial Applicability The present invention provides an automatic clutch device for an automobile which can be manually operated, and includes a first piston which is pressed against one end side of a cylinder when not in operation by a spring and a direction of the first piston while maintaining a distance from the first piston. A switching cylinder having a second piston that is biased by a spring is provided, the hydraulic oil conduit of the manual operation hydraulic fluid supply mechanism is provided on the first piston side of the cylinder, and the biasing spring of the second piston is provided. Side is connected to the hydraulic oil pipeline of the slave cylinder, and between the both pistons, the hydraulic fluid pipeline of the automatic operation hydraulic fluid supply mechanism and the pipeline to the pump pressure adjusting relief valve provided in the supply mechanism. Since a port for communicating with the oil tank when the second piston is not operating is formed in the chamber that is interposed between the second piston and the spring for the second piston of the cylinder, In addition, the hydraulic oil pipeline between the manual hydraulic oil supply mechanism and the slave cylinder does not directly communicate with each other, but is connected through the switching cylinder. Therefore, even if the automatic operation and the manual operation are switched at any time, Since the hydraulic oil returning from the slave cylinder does not flow into either of the hydraulic oil supply mechanisms, the balance of hydraulic oil in both hydraulic oil supply mechanisms is always maintained. There is no possibility that oil will flow into an oil tank that communicates and the friction clutch will suddenly become "engaged" and the vehicle will rapidly start. Also, when switching from automatic operation to manual operation when the slave cylinder is filled with hydraulic oil,
By strongly depressing the clutch pedal, the relief valve is opened and the tank is returned to the tank. Therefore, the complicated operation is not required, and the automatic operation can be easily changed to the manual operation without trouble. Further, the volume of the chamber having the biasing spring of the second piston communicating with the slave cylinder of the switching cylinder is made equal to the capacity of the pedal full stroke of the master cylinder to form a port communicating with the oil tank when the second piston is not operating. By doing so, the clutch is "disengaged"
The amount of oil for the purpose can be made constant irrespective of the amount of wear of the clutch, and there is also an effect that complicated interval adjustment of the stopper or the like when the clutch is worn as described above can be made unnecessary.

[Brief description of drawings]

FIG. 1 is a fluid circuit diagram of an example of an automobile auto clutch device of the present invention.

FIG. 2 is an overall view of a conventional automobile auto clutch device.

FIG. 3 is a schematic view showing an example of switching means in the automobile automatic clutch device shown in FIG.

FIG. 4 is a fluid circuit diagram of an example of an automobile auto clutch device which is the basis of the present invention.

[Explanation of symbols]

1 Friction clutch 2 Release bearing 3
Release fork 4 Slave cylinder 5 Clutch pedal 7,
11 Oil Tank 8 Master Cylinder 9, 16, 23 Hydraulic Oil Pipeline 12, 17, 34, 36, 51 Pipeline 10 Hydraulic Oil Supply Mechanism for Manual Operation 13 Motor 14 Gear Pump 15 Check Valve 18 Relief Valve 19 Return Pipeline 20 Electromagnetic Valve 21 Hydraulic fluid supply mechanism for automatic operation 22 Switching mechanism 22 'Electromagnetic switching valve 30, 40 Switching cylinder 3
1, 41 Cylinder 32, 42, 45 Spring 33 Piston 43
First piston 46 Second piston 35, 44 Stopper 47
1st chamber 48 2nd chamber 49 3rd chamber 50 Ports.

Front page continued (72) Inventor Hiroyuki Arai 4-1-1, Kamiodanaka, Nakahara-ku, Kawasaki-shi Transtron Co., Ltd. (72) Inventor Nobuo Sugamura 4-1-1, Kamiodanaka, Nakahara-ku, Kawasaki Within the company Transtron

Claims (1)

[Claims] 1. A slave cylinder for connecting and disconnecting a friction clutch, wherein a hydraulic fluid supply mechanism for automatic operation which is operated by a pump and a hydraulic fluid supply mechanism for manual operation which is operated by a clutch pedal are selectively provided for the cylinder. In an auto clutch device for automobiles that can be connected by pipes, when not operating between the hydraulic oil line of the hydraulic oil supply mechanism for manual operation and both hydraulic oil lines of the automatic operation hydraulic oil supply mechanism and the slave cylinder. A first piston that is pressed by a spring to one end side of the cylinder, and a second piston that is biased by the spring in the same piston direction while maintaining a distance from the first piston are provided. The volume of the chamber where the biasing spring was installed was made equal to the capacity of the pedal full stroke of the master cylinder belonging to the hydraulic fluid supply mechanism for manual operation. A replacement cylinder is provided, the hydraulic oil line of the manual operation hydraulic oil supply mechanism is connected to the first piston side of the cylinder, and the hydraulic oil line of the slave cylinder is connected to the biasing spring side of the second piston. In addition, the two pistons are interposed between a hydraulic oil pipe line of the automatic operation hydraulic oil supply mechanism and a pipe line to a pump pressure adjusting relief valve provided in the supply mechanism, and In the chamber provided with the second piston spring, a port that communicates with the oil tank when the second piston is not operating is formed.