JPH0452492Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a power clutch device for an automobile.

[Prior Art] A power clutch device that selectively operates the clutch manually or automatically when starting is known (Utility Model Application No. 59-83221 by the present applicant).
(Refer to the publication), this type of power clutch device is
Only the clutch operation when starting is done manually,
It is often used in semi-automatic transmissions in which all subsequent gear shifting operations are automated (Utility Application No. 60-34968, Utility Application No. 112461-1980 filed by the present applicant, etc.).

An example of this will be explained with reference to FIG. 2. A master cylinder 2 that operates in conjunction with a clutch pedal 1 and a clutch booster 4 that operates a clutch 3 (FIG. 1) are connected by a hydraulic circuit 5.

The master cylinder 2 has an oil reservoir 6
The oil in the air reservoir 7 is guided to the clutch booster 4 through an air circuit 9 having a normally closed relay valve 8 interposed therebetween. A piston 11 is housed in the power cylinder 10 to which the air circuit 9 is connected.
The piston 11 is adapted to drive an outer lever 3a of the clutch 3 via a clutch rod 12.

Further, another air circuit 15 is provided in parallel with the air circuit 9 via a double check valve 14, and a normally closed solenoid valve 16 is interposed in the air circuit 15. A normally open electromagnetic valve 17 is interposed. The operating parts 16a and 16b of these electromagnetic valves are connected to a control unit 19, respectively.

In this power clutch, when the driver depresses the clutch pedal 1, hydraulic pressure is generated in the master cylinder 2, which is guided to the clutch booster 4 via the hydraulic circuit 5, and the hydraulic piston 13 moves. to open relay valve 8. Then, the air in the air reservoir 7 is sent to the power cylinder 10 via the air circuit 9 to press and move the piston 11. This piston 11 rotates the outer lever 3a in the direction of the arrow through the clutch rod 12, and the clutch 3 is disengaged. When the clutch pedal 1 is released from the foot, the air in the power cylinder 10 is discharged from the electromagnetic valve 16, the piston 11 returns, and the clutch 3 is connected. Note that the double check valve 14 is a known type that communicates the higher pressure one of the two inlets with the outlet side, and if the pressure on the outlet side increases after the internal valve body moves to one side, the valve body Fluid flows from the outlet side to the inlet opposite to the moved side. That is, this double check valve 14 always allows the inlet and outlet with higher pressure to pass through, and if the inlet pressures are the same, the inlet with the higher pressure last time is communicated.

Further, when a control signal is output from the control unit 19 to the actuating parts 16a and 17a of the electromagnetic valve, the electromagnetic valve 16 opens and the electromagnetic valve 17 closes. Then, the air in the air reservoir 7 flows into the second air circuit 1.
5 to the power cylinder 10, and the clutch 3 is disengaged in the same manner as described above. When the control unit 19 stops outputting the control signal, the power cylinder 10
The air is discharged from the solenoid valve 16 in the same manner as described above, and the clutch 3 is connected.

In such a device, when the clutch 3 is disengaged by the control unit 19, the hydraulic piston 13 in the clutch booster 4 is forcibly moved to the left in the illustrated example, thereby increasing the volume of the hydraulic pipe 5 and creating a negative pressure. occurs and sucks in air, and as a result, the subsequent travel distance of clutch pedal 1 changes,
This has the disadvantage of overstroke.

[Purpose of the invention] Therefore, the purpose of the invention is to prevent the clutch pedal from changing its travel distance and causing overstroke after the clutch is disengaged without using the clutch pedal's master cylinder and the clutch booster's hydraulic cylinder. An object of the present invention is to provide a power clutch device for an automobile that prevents such problems.

[Structure of the invention] According to the invention, the master cylinder 2 which is interlocked with the clutch pedal 1 and the clutch booster 4 which operates the clutch 3 are connected by the hydraulic circuit 20, and the clutch booster 4 and the air reservoir 7 are connected to the first air In an automobile power clutch device connected by a circuit 22, a normally open solenoid valve 21 and an inlet of a double check valve 14 are interposed in the hydraulic circuit 20 from the master cylinder 2 side. Another inlet is connected to the air reservoir 7 via a second air circuit 23, and a normally closed solenoid valve 16 and a power cylinder 24 are interposed in the second air circuit 23 from the air reservoir 7 side. , 21 are each connected to a control unit 25, which opens the electromagnetic valve 16 and closes the electromagnetic valve 21 when the clutch 3 is disengaged.

[Operation and effect of the invention] Therefore, when the clutch is disengaged without using the master cylinder and hydraulic cylinder, the oil from the power cylinder flows into the hydraulic piping, compensating for the increase in the volume of the hydraulic piping due to the movement of the hydraulic piston. do. Therefore, it is possible to prevent the generation of negative pressure and the suction of air, and as a result, it is possible to prevent overstroke due to a change in the pedal stroke of the clutch pedal.

Furthermore, since the normally open solenoid valve on the upstream side of the double check valve is closed, negative pressure will not be generated in the hydraulic circuit even if the double check valve should fail.

[Example] An example of the present invention will be described below with reference to FIG. In FIG. 1, parts corresponding to those in FIG. 2 are given the same reference numerals and redundant explanation will be omitted.

In the figure, the master cylinder 2 and clutch booster 4 are connected through a hydraulic circuit 20, and the clutch booster 4 and air reservoir 7 are connected through a first air circuit 2.
Connected by 2.

This hydraulic circuit 20 is provided with a normally open electromagnetic valve 21 and a double check valve 14 in order from the master cylinder 2 side. One inlet of this double check valve 14 is connected to the second air circuit 23.
It is connected to the air reservoir 7 by. This second air circuit 23 is equipped with a normally closed electromagnetic valve 16 and a power cylinder 24 that converts air pressure into oil pressure in order from the air reservoir 7 side, and an oil chamber 24c of the power cylinder 24. is connected to the double check valve 14. Then, the electromagnetic valves 16, 21 have actuating parts 16a, 21.
a are connected to a control unit 25, respectively.

In operation, when the clutch pedal 1 is depressed, the clutch 3 is disengaged, which is the same as in the conventional device.

When the control unit 25 disengages the clutch 3,
A control signal is output to the actuating parts 16a and 21a of the electromagnetic valve, the electromagnetic valve 16 is opened, and the electromagnetic valve 2 is opened.
Close 1. Then, air in the air reservoir 7 flows through the second air circuit 23 to the air chamber 24a of the power cylinder 24, moving the piston 24b downward in the illustrated example. Therefore, the oil in the oil chamber 24c is compressed and sent from the double check valve 14 to the hydraulic circuit 20, and the clutch 3 is disengaged in the same manner as described above. At this time, the hydraulic piston 13 moves to the left, but the increased volume of the hydraulic piping 20 due to the leftward movement is compensated for by the oil from the oil chamber 24c. Therefore, generation of negative pressure in the hydraulic pipe 20 is prevented, and air is prevented from being sucked in. As a result, the pedal stroke of the clutch pedal 1 will not change and overstroke will not occur. Note that the solenoid valve 21 serves as a safety valve that prevents negative pressure in the hydraulic piping 20 when the double check valve 14 fails.

[Summary] As explained above, according to the present invention, it is possible to prevent negative pressure in the hydraulic piping, to prevent air from being sucked in, and to prevent changes in the pedal stroke of the clutch pedal.

[Brief explanation of drawings]

FIG. 1 is an overall configuration diagram showing an embodiment of the present invention;
FIG. 2 is an overall configuration diagram showing a conventional device. 1... Clutch pedal, 2... Master cylinder, 4... Clutch booster, 13... Hydraulic piston, 14... Double check valve, 22... First air circuit, 23... Second air circuit, 24...Power cylinder, 24c...Oil chamber, 25...Control unit.

Claims (1)

[Scope of utility model registration request] Master cylinder 2 linked to clutch pedal 1
and a clutch booster 4 that operates the clutch 3 are connected by a hydraulic circuit 20.
and air reservoir 7 are connected through a first air circuit 22. In the power clutch system of an automobile, a normally open electromagnetic valve 21 and an inlet of a double check valve 14 are connected to the hydraulic circuit 20 from the master cylinder 2 side. The other inlet of the double check valve 14 is connected to the air reservoir 7 via a second air circuit 23.
3 is a normally closed solenoid valve 16 from the air reservoir 7 side.
and a power cylinder 24 are interposed, and the electromagnetic valves 16 and 21 are each connected to a control unit 25, and the control unit 25 opens the electromagnetic valve 16 and closes the electromagnetic valve 21 when the clutch 3 is disengaged. Automotive power clutch device.