JPS6229653B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a hydraulic actuation circuit for a clutch actuator for actuating a clutch by a hydraulic actuator.

This type of automatic clutch releases the clutch by applying fluid pressure to a fluid pressure actuator.
When the fluid pressure is released, the clutch is engaged, and the supply and discharge of this fluid pressure is controlled by an electronic control device according to vehicle conditions such as starting, stopping, and shifting during engine operation.

By the way, when the engine is stopped, that is, when the engine is parked or parked, the fluid pressure of the actuator is released in order to ensure the durability of the clutch components such as the clutch spring, hydraulic equipment, and sealing material. In order to prevent battery discharge, the power switch of the electronic control unit is linked to the ignition switch of the engine.

In this case, when you turn off the ignition switch to stop the engine, the current to the solenoid valve that applies fluid pressure to the actuator is immediately cut off, the fluid pressure in the actuator is released, and the clutch suddenly engages. Ru. On the other hand, even if the ignition switch is turned off, the engine continues to rotate for a short time due to inertia, so if the transmission is in a position other than neutral, the engagement of the clutch may cause a shock or the car to suddenly jump out. There is a danger of

To solve this problem, we installed a delay circuit in the electronic control unit's power circuit to delay the opening of the solenoid valve until the engine has completely stopped, even after the ignition switch is turned off. This is proposed in Japanese Patent Publication No. 13857/1983.

However, this prior art requires a delay circuit, and the durability and reliability of this delay circuit are not necessarily satisfactory.

The present invention has been devised in view of the above points, and by disposing a second discharge pipe having a flow rate limiting function in place of the delay circuit, the engine can be operated when the transmission is in a state other than neutral. It is an object of the present invention to provide a fluid pressure operating circuit for a clutch actuator that can prevent the vehicle from jumping out even when the vehicle is stopped.

Hereinafter, the present invention will be specifically explained based on illustrated embodiments.

In the figure, 1 is the engine flywheel, 2
is a dry single plate type clutch, which includes a clutch pressure plate 2a, a clutch disk 2b disposed between the pressure plate 2a and the engine flywheel 1, and the pressure plate 2a.
a diaphragm spring 2c that presses the diaphragm spring 2c, a clutch release bearing 2d that operates the diaphragm spring 2c, and the release bearing.
Clutch release lever 2e that operates 2d,
It includes the release lever 2e and a lever 2g connected at one end by a clutch shaft 2f.

3 is a clutch actuator, and a piston rod 3b of a piston 3a thereof is rotatably connected to the other end of the lever 2g by a pin 3c. The clutch actuator hydraulic pressure chamber A is connected to a hydraulic pump 5, which is a hydraulic pressure source, through a pipe 4a.

Reference numeral 6 denotes an accumulator disposed in the piping 4a, and numeral 7 denotes an electromagnetic supply valve disposed in the piping 4a, which is normally closed and opens when energized.

The hydraulic action chamber A of the actuator 3 is connected to a first return pipe 4d that opens into the oil tank 8.
An electromagnetic discharge valve 9 which is normally closed and opens when energized is disposed in the discharge pipe 4b.

The hydraulic chamber A of the actuator 3 also includes a second discharge pipe 4c that is arranged in parallel with the first discharge pipe 4b and connected to the return pipe 4d.
An electromagnetic on-off valve 10 equipped with a throttle that is normally open and closed when energized is disposed in the second discharge pipe 4c. In addition,
The second discharge pipe 4c may be of any type as long as it has a function of restricting the flow rate of flowing oil, and in addition to the above-mentioned arrangement in which the electromagnetic on-off valve 10 is provided with a throttle, an orifice may be provided in the pipe 4c. Alternatively, the pipe 4c itself may be made of a thin material. The other chamber B of the actuator 3 is the return pipe 4d.
is in contact with.

Reference numeral 11 denotes an electronic control device composed of a microcomputer, which controls a clutch position sensor 12 disposed opposite to a rod 3d connected to a piston 3a of the clutch actuator 3, and a clutch position sensor 12 that measures the rotational speed of the flywheel 1. An engine rotation sensor 13 detects, an accelerator sensor 15 detects the operating position of the accelerator pedal 14, and a vehicle speed sensor 18 detects the rotation speed of the output shaft 17 of the transmission 16.
The electromagnetic supply valve 7 based on input signals from etc.
Controls the electromagnetic discharge valve 9 and the electromagnetic on-off valve 10.

Reference numeral 19 denotes a power switch disposed in the wiring connecting the electronic control device 11 and the power source 20, and linked to the ignition switch.

Next, the operation of the device of the present invention will be explained.

Based on the shift signal, the output from the electronic control device 11 energizes the electromagnetic supply valve 7 to open it, cuts off the energization to the electromagnetic discharge valve 9 and closes it, and energizes the electromagnetic on-off valve 10 to close it. Close the circuit.
As a result, from the accumulator 6 to the electromagnetic supply valve 7
Hydraulic pressure is supplied to the hydraulic chamber A of the clutch actuator 3 through the clutch actuator 3, and the piston 3a is moved to the right, causing the clutch 2 to be disengaged.

When the predetermined speed change operation is completed after the clutch is disengaged, the power to the electromagnetic supply valve 7 is cut off to close it, and the electromagnetic discharge valve 9 is energized to open it, and as a result, the pressure oil in the hydraulic action chamber A of the actuator 3 is released. is discharged through the electromagnetic discharge valve 9, the clutch 2 is engaged, and the vehicle is driven in a new gear. The speed of clutch engagement may be controlled by pulse-controlling the energization to the electromagnetic discharge valve 9,
It is also possible to perform fine speed control by using the valve in conjunction with pulse control of the valve.

Next, a case will be described in which the engine is stopped after the vehicle has stopped.

The vehicle slows down to stop the vehicle,
For example, when the vehicle speed is below 12 km/h and the accelerator pedal is released, or when the engine speed is below 400 rpm, the electromagnetic supply valve 7 is activated by the output from the electronic control unit 11 to prevent the engine from stalling. is opened, the electromagnetic discharge valve 9 and the electromagnetic on-off valve 10 are closed, the clutch actuator 3 is operated, the clutch 2 is disengaged, and the vehicle is stopped. In this way, the clutch is disconnected when the vehicle is stopped, but when the ignition key is turned off to stop the engine, the power switch 19 linked to this is also turned off, so the electronic control unit 11 does not function. As a result, the electromagnetic supply valve 7, the electromagnetic discharge valve 9, and the electromagnetic shut-off valve 10 are not energized. Therefore, only the electromagnetic on-off valve 10, which is a normally open valve, is opened, and the pressure oil in the hydraulic action chamber A of the clutch actuator 3 is slowly discharged from this throttled on-off valve 10, so that the clutch 2 By slowly engaging the clutch, when the clutch is engaged, it is no longer affected by the rotational inertia of the engine even if the transmission is in first gear or reverse, for example.

As explained in detail above, the present invention includes, in addition to a normal discharge pipe, a second discharge pipe having a flow rate restriction function that is arranged in parallel with this discharge pipe, and a second discharge pipe that has a flow rate restriction function. Since it is equipped with a normally open on-off valve that is normally open and closed when the power is applied, it is possible to park in first gear or reverse without providing an electrical delay circuit as in the prior art. When attempting to do so, it is possible to prevent the vehicle from jumping out or being shocked due to sudden engagement of the clutch when the engine is stopped.

[Brief explanation of the drawing]

The figure is a circuit diagram of the device of the present invention. 1...Engine flywheel, 2...Clutch,
3...Clutch actuator, 4a...Piping, 4b
...first discharge pipe, 4c...second discharge pipe,
5... Hydraulic pump, 6... Accumulator, 7... Electromagnetic supply valve, 8... Oil tank, 9... Electromagnetic discharge valve, 10
...Electromagnetic on-off valve, 11...Electronic control device.

Claims (1)

[Claims] 1 Piping that has a normally closed electromagnetic supply valve and communicates the fluid pressure acting chamber of the clutch actuator with a fluid pressure source, and a normally closed electromagnetic discharge valve that connects the fluid pressure acting chamber and return piping. a first discharge pipe that communicates with the
A second discharge pipe that is arranged in parallel with the first discharge pipe and has a flow rate restriction function, and a normally open type that is normally open and closed when energized is located in the second discharge pipe. The clutch actuator is provided with an on-off valve and a control means for supplying a control signal to each of the valves to control on/off of the clutch, and slowly operates the clutch actuator when the control signal from the control means disappears. A fluid pressure operating circuit for a clutch actuator, characterized in that: