JPH0481046B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION a. Field of Industrial Application The present invention relates to a booster-type clutch operating device that is mainly installed on trucks, buses, etc., and particularly to a hydraulic pressure supply system on the master cylinder side when the clutch pedal is released. The present invention relates to a clutch operating device configured to enable the power piston of a booster to reciprocate independently without any adverse effects.

b. Prior Art A booster type clutch operating device is generally employed in large vehicles such as trucks and buses.
This booster-type clutch operating device is configured to convert hydraulic pressure supplied from a master cylinder into air pressure using a relay valve, and use this air pressure to move the power piston of the booster forward and disengage the clutch. .

By the way, in this type of clutch operating device, in order to make the amount of depression of the clutch pedal correspond to the amount of stroke of the power piston, for example, as shown in FIG. It is connected to the liquid chamber 5. Since the volume of this oil chamber 5 increases or decreases in accordance with the stroke amount of the power piston 6, the amount of depression of the clutch pedal completely corresponds to the stroke amount of the power piston, and the driver can engage or disengage the clutch or half-clutch it. Operations can be performed accurately. Note that the configuration of other parts in FIG. 4 is unrelated to the above description.

c Problems to be Solved by the Invention However, some recent clutch operating devices are equipped with a drive means that independently reciprocates the power piston 6 when the clutch pedal 9 is released. The aforementioned clutch pedal depression amount and power piston 6
There is a risk that the correspondence relationship between the stroke amount and the stroke amount may deviate. FIG. 4 shows an example of a clutch operating device in which the power piston 6 is configured to be able to reciprocate independently.This device is particularly useful when the clutch pedal is pressed when the transmission (not shown) is in neutral and the vehicle is stopped. 9 is released, the power piston 6 is moved forward by the driving means and the clutch is disengaged. ). That is,
In the figure, 10 is a manual switch, 11 is a neutral switch, and 12 is a vehicle stop switch. When these switches 10 to 12 are all turned on, the solenoid valve 13 enters the supply mode, and the pressure in the air tank 14 changes to the double check valve 15. The power piston 6 moves forward in the direction of arrow a in the figure, and the clutch lever 17 operates in the cross direction. In this way, when the clutch is disengaged, the countershaft of the transmission stops, which eliminates gear mesh noise and reduces fuel consumption at idle.

However, when the power piston 6 moves forward with the clutch pedal 9 released, the oil in the reservoir 18 of the master cylinder 1 is sucked into the oil chamber 5 as the volume of the oil chamber 5 increases. Therefore, if the clutch pedal 9 is depressed in an attempt to start the vehicle from this state, excessive oil is supplied to the oil chamber 5, causing the clutch lever 17 to move too far in the opposite direction. For this reason, there is a risk of damage to the clutch body due to overstroke, and even if the clutch pedal 9 is returned after operating the transmission to engage a gear, the clutch will not engage unless the amount of depression is very shallow. In some cases, even if the clutch pedal 9 is completely released, the clutch may not connect immediately and may cause a problem where it connects after a while. Of course, the above-mentioned problems cannot be avoided by turning off the manual switch 10 before depressing the clutch pedal 9 and waiting for the power piston 6 to return to its original position. It is extremely complicated to switch.

The aforementioned discrepancy in the correspondence between the amount of depression of the clutch pedal and the amount of stroke of the power piston 6 is not a problem specific to the clutch operating device shown in FIG. There is also room for this to occur as well.

The present invention was developed in order to effectively solve the above-mentioned problems, and the purpose is that when the clutch pedal is depressed while the power piston is moving forward alone, the clutch lever will overstroke. To provide a clutch operating device which prevents the clutch pedal from changing and prevents the connection position from changing when the clutch pedal is returned.

d Means for solving the problem In order to solve the problem of the above-mentioned conventional technology,
In the present invention, the master cylinder is actuated by the clutch pedal, and the power piston is reciprocated in accordance with the amount of working fluid supplied by the actuation of the master cylinder. In a clutch operating device configured to engage and disengage a clutch, a driving means for moving the power piston forward using compressed air when the clutch pedal is released is provided, and the power piston is slidably provided. A large diameter cylinder is connected to a small diameter cylinder located at the rear of the reciprocating side of the power piston and having a manual piston slidably disposed separately from the power piston. and one end surface of the manual piston to define a pressure chamber to which the compressed air is supplied, and an oil fluid for moving the manual piston forward from the master cylinder is supplied to the other end surface of the manual piston. The power piston is configured to define a liquid chamber in which the manual piston presses the power piston in the forward movement direction when the manual piston moves forward when the driving means is inactive.

e Effect: In the clutch operating device of the present invention, the manual piston is separately disposed behind the power piston on the backward movement side, so the power piston can be moved forward by the driving means while the clutch pedal is released. However, the manual piston remains stopped, so the hydraulic pressure supply system on the master cylinder side is not affected at all, and the correspondence between the amount of depression of the clutch pedal and the amount of stroke of the power piston is maintained accurately. Moreover, the connection position of the clutch pedal does not change.

In addition, even if the manual piston is moved forward when the power piston has completed forward movement, the pressure in the pressure chamber will be reduced due to the compressibility of the working fluid of the power piston, which is compressed air, and the small diameter of the pressure receiving part of the manual piston. remains virtually unchanged;
Even if the clutch pedal is depressed from a stopped state with the engine still running, there will be no problem in which the power piston is moved further forward and overstroke occurs before the manual piston contacts the power piston.

f Embodiment An embodiment of the present invention will be described below based on FIGS. 1 to 3. In the figure, reference numeral 23 denotes a pneumatic booster, and a power piston 25 is slidably disposed within a large-diameter cylinder 24 constituting the booster 23. The inside of the cylinder 24 is divided into a pressure chamber 26 and an atmospheric chamber 27 by the power piston 25, and the power piston 25 is moved forward to the right in FIG. 1 by the air pressure supplied to the pressure chamber 26. It's summery.

Piston rod 2 integrated with power piston 25
8 is connected to a clutch lever 31 via a relay piston 29 and a connecting rod 30, and when the power piston 25 moves forward as shown in FIGS. 2 and 3, the clutch lever 31 rotates clockwise in the same figures. A clutch (not shown) is then disengaged.

A manual cylinder 32 having a smaller diameter than the cylinder 24 is attached to the rear part of the booster 23 (at the rear position on the backward movement side of the power piston 25) so as to be connected to the cylinder 24. A manual piston 33 is disposed inside this cylinder 32.
2 is partitioned by a piston 33 into an oil chamber 24 and a pressure chamber 26a. In other words, the pressure receiving area of the manual piston 33 is equal to that of the power piston 25.
It is formed smaller than the pressure receiving area of. Also,
The pressure chamber 26 is defined between one end surface of the power piston 25 and one end surface of the manual piston 33. The pressure chamber 26 is supplied with compressed air from a driving means to be described later. The manual piston 33 is configured to move toward the right in FIG. 1 by the hydraulic pressure supplied to the hydraulic chamber 34 on the other end side.
Therefore, the working fluids of the power piston 25 and the manual piston 33 are different, and the power piston 25 is moved forward by compressed air, and the manual piston 33 is moved forward by oil fluid. Note that the pressure chamber 26a is configured as a part of the pressure chamber 26 of the booster 23.

The oil chamber 34 is connected to the master cylinder 1 by a hydraulic pipe 38, and when the clutch pedal 9 is depressed, the oil in the master cylinder 1 is supplied to the oil chamber 34 through the hydraulic pipe 38. A relay valve 19 is connected to the oil chamber 34,
The pressure in the air tank 39 is regulated by the relay valve 19 to a pressure corresponding to the pressure in the oil chamber 34,
This pressure is supplied to the pressure chamber 16 of the booster 3 via the double check valve 15.

The air tank 39 is connected to the double check valve 15 via a supply solenoid valve 40, and the solenoid valve 40
When turned ON (open), the pressure in the air tank 39 is supplied to the double check valve 15. The valve body 15a of the double check valve 15 is operated by the supply pressure from the relay valve 19 or the solenoid valve 40, and shuts off the low pressure side and connects the high pressure side to the pressure chamber 2.
It is designed to be connected to 6. Supply solenoid valve 4
An exhaust solenoid valve 41 is connected between the double check valve 15 and the double check valve 15, and the solenoid valve 40 is turned on (opened) when the valve body 15a of the double check valve 15 is in the position shown in FIGS. ), the air in the pressure chamber 26 of the booster 23 is exhausted from the solenoid valve 41. Note that the supply solenoid valve 40 and the exhaust solenoid valve 41 are connected to the power piston 25.
constitutes a driving means.

A manual switch 43 , a neutral switch 44 , a clutch release switch 45 , and a stop switch 46 are arranged in series between the supply solenoid valve 40 and the power supply 42 .
The supply solenoid valve 40 is configured to be turned on (opened) when all of the valves 3 to 46 are turned on.
The neutral switch 44 is based on the output of a first detection means (not shown) that detects the neutral state of the transmission.
The neutral switch 44 is configured to be turned ON and OFF when the transmission is in neutral. In addition, the clutch release switch 45
is the second one that detects the released state of the clutch pedal 9.
The clutch release switch 45 is turned on and off based on the signal output of a limit switch 47 as a detection means, and the clutch release switch 45 is turned on when the clutch pedal 9 is released. Further, the stop switch 46 is turned on and off based on the signal output of a limit switch 48 which detects that the power piston 25 of the booster 23 has completed its forward movement, and when the power piston 25 has completed its forward movement. Otherwise, the stop switch 46 is configured to be turned on.

On the other hand, the exhaust solenoid valve 41 is turned on and off based on the signal output of a limit switch 49 as a third detection means for detecting the depressed state of the clutch pedal 9.
The solenoid valve 41 is configured to turn on (open) when the clutch pedal 9 is depressed.

The clutch operating device is constructed as described above, and when the manual switch 43 is turned on to put the transmission in neutral when the vehicle is stopped, and the clutch pedal 9 is released, the solenoid valve 40 is turned on (opened) and the air tank 39 is opened. Pressure double check valve 15
The pressure chamber 26 of the booster 23 is directly supplied via. The power piston 25, to which pressure is supplied to the pressure chamber 26, separates from the rod 33a of the manual piston 33 and moves forward independently, as shown in FIG. 2, and the clutch is disengaged. As a result, the countershaft of the transmission stops rotating, eliminating gear mesh noise and reducing idling fuel consumption. In addition, at this time, the manual piston 33 is connected to the pressure chamber 26.
Since the oil chamber 34 is held in the non-operating position by the air pressure of
No. 8 oil is not sucked into the oil chamber 34.

When the power piston 25 completes forward movement, the stop switch 46 is turned OFF, and the supply solenoid valve 4 is turned off.
0 becomes OFF (closed). Therefore, compressed air is held in the pressure chamber 26 of the booster 23, and the power piston 25 is held in the forward movement position shown in FIG.

Next, when the clutch pedal 9 is depressed to start the vehicle from the state shown in FIG.
4. The pressure in the oil chamber 34 is equal to the pressure in the pressure chamber 26.
When the pressure rises above , the manual piston 33
moves forward as shown in FIG. 3, and the tip of the rod 33a of the manual piston 33 touches the power piston 25.
comes into contact with. Note that the manual piston 33 is formed to have a smaller diameter than the power piston 25, and the working fluid of the power piston 25 is compressed air, so even if the manual piston 33 moves forward and enters the pressure chamber 26, the power piston 25 will not be further The pressure in the pressure chamber 26 does not change as the forward movement reaches overstroke.

When the clutch pedal is further depressed from this state, the pressure in the oil chamber 34 further increases, and the relay valve 19 applies a pressure comparable to the pressure in the pressure chamber 26 to the double check valve 15. At this time,
When the pressure supplied from the solenoid valve 40 is higher, the valve body 15a of the double check valve 15 is in the position shown in FIG. In this state, the exhaust solenoid valve 41 is turned on (opened) by depressing the clutch pedal 9.
When this happens, the compressed air in the pressure chamber 26 of the booster 23 is immediately exhausted from the solenoid valve 41, and then the valve body 15a of the double check valve 15 is switched as shown in FIG. 19 and the double check valve 15 to the pressure chamber 26 again. In addition, solenoid valve 4
Manual piston 33 even if exhaust is done from 1
The tip of the rod 33a is already attached to the power piston 25.
Since the power piston 25 is in contact with the manual piston 33, there is no risk of the power piston 25 rapidly moving back and impacting the manual piston 33.

When the clutch pedal 9 is gradually released after shifting the transmission gear with the clutch pedal 9 depressed, the pressure in the oil chamber 34 of the manual cylinder 32 and the pressure in the pressure chamber 26 of the booster 23 gradually decrease. The manual piston 33 and the power piston 25 move back together to smoothly connect the clutch. Note that the amount of depression of the clutch pedal 9 and the position of the power piston 25 at this time are always constant because the volume of the oil chamber 34 does not change when the power piston 25 moves forward alone as described above.

Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment and can be modified in various ways. For example, in the above embodiment, the depression state of the clutch pedal is detected by the limit switch 49, but the ON/OFF state is detected by the pressure in the oil chamber 34.
It is also possible to detect the above-mentioned depression state by a pressure switch. Furthermore, by detecting the position of the manual piston 33 using a limit switch, it is also possible to detect the depressed state.

g. Effects of the Invention According to the clutch operation device of the present invention, even if the power piston is moved forward alone when the clutch pedal is released, the hydraulic pressure supply system on the master cylinder side is not affected at all, and the amount by which the clutch pedal is depressed The correspondence between the stroke amount of the power piston or the degree of engagement of the clutch is accurately maintained.

Furthermore, in the operating device of the present invention, by providing a detection means for detecting the neutral state of the transmission and the released state of the clutch pedal, the clutch can be automatically engaged without depressing the clutch pedal each time the vehicle is stopped, for example. This eliminates the gear meshing noise of the transmission and improves idle fuel efficiency.

Furthermore, according to the operating device of the present invention, even if the manual piston is moved forward when the power piston has completed its forward movement, the pressure in the pressure chamber will substantially change because the pressure chamber is air pressure and is compressible. Therefore, even if you depress the clutch pedal from a stopped state with the engine running, the manual piston will not cause the power piston to move further forward, resulting in overstroke, and the clutch lever will not move. is maintained in the disconnected position to avoid interference between automatic and manual operation.

[Brief explanation of the drawing]

1 to 3 are schematic diagrams of a clutch operating device according to the present invention, and FIG. 4 is a schematic diagram of a conventional clutch operating device. 1... Master cylinder, 9... Clutch pedal, 15... Double check valve, 19... Relay valve, 24... Cylinder, 25... Power piston, 26... Pressure chamber, 27... Atmospheric chamber, 28...
...Piston rod, 30...Connection rod, 31...
...Clutch lever, 32...Manual cylinder, 33...Manual piston, 33a...Rod, 34...Hydraulic chamber, 39...Air tank, 4
0... Solenoid valve for supply (driving means), 41... Solenoid valve for exhaust (driving means).

Claims (1)

[Claims] 1 The master cylinder is actuated by the clutch pedal, the power piston is reciprocated in response to the amount of working fluid supplied by the actuation of the master cylinder, and the clutch is connected and disconnected by the reciprocating movement of the power piston. In the clutch operating device, the power piston is slidably disposed in a large-diameter cylinder, which is provided with driving means for reciprocating the power piston using compressed air when the clutch pedal is released. and a small-diameter cylinder located at the rear of the reciprocating side of the power piston and having a manual piston slidably disposed separately from the power piston, so that one end surface of the power piston and the manual piston are connected to each other. A pressure chamber to which the compressed air is supplied is defined between one end surface of the manual piston, and a liquid chamber is defined on the other end surface of the manual piston to which an oil fluid for reciprocating the manual piston is supplied from the master cylinder. A clutch operating device characterized in that the manual piston is configured to press the power piston in the forward movement direction when the manual piston moves forward with the drive means inactive.