JPS60151421A - Clutch control circuit - Google Patents

Abstract

PURPOSE:To contrive to lessen pedal operating force and to speed up the response by a structure wherein, when the working fluid pressure at oil pressure source is higher than the predetermined working fluid pressure, a hydraulic piping to engage a clutch through a back pressure valve is communicated to the oil pressure source, while, when lower, said piping is communicated to a reservoir. CONSTITUTION:An oil hydraulic pipe 5a in the delivery side of an oil hydraulic pump 5 is connected on one hand to the displacement chamber 1f of an oil hydraulic actuator 2 through a back pressure valve 8, an oil hydraulic directional control valve 3 and an oil hydraulic pipe 3a and on the other hand to the displacement chamber 1e of the oil hydraulic actuator 2 through a pressure control circuit 4 and an oil hydraulic pipe 7a. Further, the oil hydraulic pipe 7a is connected through a back pressure valve 7 to a reservoir 5d. Furthermore, an unloader valve 6 is interposed between the oil hydraulic pipes 5a and 7a. One pilot pipe 5c of the oil hydraulic directional control valve 3 is communicated to the oil hydraulic pipe 5a, while the other pilot pipe 7b of the valve 3 is communicated to the oil hydraulic pipe 7a.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a clutch control circuit in a power transmission system of an automobile.

2. Description of the Related Art Operation of a clutch in a power transmission system in an automobile, particularly a truck, requires a large amount of pedal effort.

For this reason, NM of such pedal force greatly contributes to reducing driver fatigue.

In addition, if hydraulic energy is used to operate the clutch in order to reduce the pedal force, it is possible to reduce the pedal force and at the same time, you can expect a good-feeling clutch operation due to its good responsiveness.However, No method has been found in which the clutch is operated solely by such a hydraulic circuit.

An object of the present invention is to provide a clutch control circuit in which the latch operation as described above is performed by a hydraulic circuit.

The configuration of the first aspect of the present invention is as follows.

The clutch consists of a clutch plate that is linked to the engine shaft,
111. The hydraulic actuator is comprised of another clutch plate that selectively engages and disengages from the clutch plate and is interlocked with the input shaft of the transmission, and a hydraulic actuator that operates the other clutch plate.

(a) The clutch plate and the other clutch plate are disengaged by pressure oil flowing from one hydraulic pipe, and b: Pressure oil flowing from the other hydraulic pipe causes njf to disengage.
In the above configuration consisting of the above a and b, in which the other clutch plate is engaged, C: One hydraulic pipe line is connected to the discharge hole of the hydraulic pump. Pressure oil from the connected hydraulic power source flows in through the pressure control circuit, and a portion of the pressure oil that has flowed into the valve is discharged into the reservoir through one of the back pressure valves, d: 1ifj Pressure control Pressure control, restricting the flow of pressure oil from the hydraulic source to the one hydraulic pipe! By changing the pressure, the value of the hydraulic pressure in the hydraulic source is changed, and the change in the hydraulic pressure output is operated by an external signal e: The other hydraulic pipe line is configured to change the hydraulic pressure in the hydraulic source connecting to said hydraulic pressure source via a valve and other back pressure valve;
f: The hydraulic pressure switching valve 1iii is such that when the hydraulic pressure in the hydraulic source is equal to or higher than a predetermined hydraulic pressure (p d) higher than the hydraulic pressure in the one hydraulic pipe, the hydraulic pressure switching valve When the hydraulic pressure source is set to communicate with the other hydraulic pipe via the other back pressure valve, and the hydraulic pressure in the hydraulic source is lower than the predetermined hydraulic pressure (pd), the The other hydraulic pipe line communicates with the reservoir, and consists of the above configuration.

The effects of the first aspect of the present invention described above are as follows.

Pressure oil flows into one hydraulic pipe from a hydraulic source via a pressure control circuit, and one back pressure valve is interposed between one hydraulic pipe and the reservoir. The back pressure valve keeps one hydraulic line at a constant working pressure.

In addition, the pressure control circuit is capable of squeezing and releasing a portion of the pressure oil from the hydraulic source to one of the hydraulic pipes, which is kept at a constant pressure, by an external signal.
The working pressure in the hydraulic source can be reduced to the value of the working pressure in one of the hydraulic pipes.

On the other hand, another back pressure valve is interposed between the other hydraulic pipe and the hydraulic power source, and a hydraulic switching valve is interposed between the other back pressure valve and the other hydraulic pipe. However, when the hydraulic pressure in the hydraulic source is equal to or higher than a predetermined hydraulic pressure (PD) that is higher than the hydraulic pressure in one of the hydraulic pipes, the hydraulic pressure switching valve switches the other back pressure valve. It is set so that it communicates with the other hydraulic pipe line through it.

Therefore, when the clutch engages in this state, pressure oil flows from the hydraulic source side to the other hydraulic pipe side in the other back pressure valve, and in the trust back pressure valve, the flow maintains a constant pressure. A loss occurs, and as a result, the other hydraulic line is at a working hydraulic pressure that is the working hydraulic pressure at the hydraulic source minus a certain differential pressure corresponding to the pressure loss.

That is, the working oil pressure in the hydraulic source can be changed from the lowest value to the value in one hydraulic pipe to an arbitrarily set high pressure value, and when the hydraulic pressure source and the other hydraulic pipe are in communication, The working oil pressure in the other hydraulic conduit is reduced by a certain pressure difference from the working oil pressure of the changing oil pressure source.

This means that in the above state, the working pressure in the other hydraulic line is increased from a value equal to the working pressure in one hydraulic line to an arbitrarily set high value i! This makes it possible to perform continuous operations.

In the above setting state, when the working oil pressure in the hydraulic source falls below the predetermined value mentioned above, the hydraulic switching valve connects the other hydraulic line to the reservoir, so that the other hydraulic line is at atmospheric pressure. As a result, the working pressure in one hydraulic pipe is higher than that in the other pipe. When the hydraulic pressure is lower than the working pressure, the pressure oil from one hydraulic line flows into the hydraulic actuator, disengaging the other clutch plate from the clutch plate, and vice versa. When the hydraulic pressure is higher than the working pressure in one hydraulic pipe, the pressure oil from the other hydraulic pipe is applied to the hydraulic actuator, causing the other clutch plate to engage with the clutch plate. become.

As is clear from the explanation in Section 2, the effects of the first invention in the present invention are as follows.

■) If the signal that operates the pressure control circuit is linked to the clutch pedal operated by the driver, the clutch will be operated by a hydraulic actuator, so it will not be used for clutches that require a large pedal force, such as in trucks or buses. can be operated with a light pedal effort.

As a result, driver fatigue can be reduced.

2) If the signal for operating the pressure control circuit is used for control in conjunction with the speed change operation of a gear transmission in an automobile, it becomes possible to eliminate the driver's clutch operation and further reduce the driver's effort.

Moreover, in contrast to the above-mentioned first invention of the present invention, the second invention of the present invention is as follows.

In addition to the invention of the vSl in the present invention, the other hydraulic pipe line is connected to the reservoir via a pipe line having a throttle flow path.

l-Distribution The effects of the second invention in the present invention are as follows.

”-In the operation of the first invention, when the working pressure in the other hydraulic pipe reaches a higher value than the working pressure in one of the hydraulic pipes, the hydraulic actuator engages the clutch; When the movement of the hydraulic actuator stops due to the onset of engagement, the flow of pressure oil from the hydraulic source to the other hydraulic line almost stops, and as a result, no differential pressure occurs at the other back pressure valves. .

The fact that this differential pressure no longer occurs means that when the clutch begins to engage, the working oil pressure in the other hydraulic line quickly becomes equal to the working oil pressure in the hydraulic source;
Thereby, the rapidly rising hydraulic pressure in the hydraulic source rapidly increases the clutch suppression and the transmitted torque between the clutch plate and the other clutch plates.

In this way, if the transmission torque in the clutch increases rapidly, unless the clutch is operated delicately, the torque transmission in the clutch is likely to suffer #i shock.In such a case, Either the driver delicately operates the clutch φ petal linked to the operation of the pressure control circuit to prevent the shock from occurring, or the sudden change in the working oil pressure in the other hydraulic line is controlled by pressure control. There is also a method of feeding back the signal that operates the circuit and performing delicate control by comparing the feedback signal and the signal that controls the pressure control circuit.However, in this second invention, the other hydraulic pressure Since a throttle flow path is interposed between the pipe and the reservoir,
A portion of the pressure oil in the hydraulic source is constantly flowing out to the reservoir via other back pressure valves, hydraulic switching valves, and the other hydraulic line, and this causes the movement of the hydraulic actuator to stop. Even in a state where the back pressure valve is turned off, a pressure difference is always generated in the other back pressure valves, so that the working pressure in the other hydraulic pipe does not become the working pressure in the hydraulic power source.

In this way, the effect of the first and second invention is that by simply interposing a throttle flow path between the other hydraulic pipe and the reservoir, the clutch can be engaged without any delicate latch operation or delicate control. This allows for smooth torque transmission when the engine is engaged.

The configuration of the third aspect of the present invention is as follows.

In addition to the first aspect of the present invention, one hydraulic conduit is configured to eject pressure oil toward each actuating portion of the clutch via the other throttle flow path.

The effects of the third aspect of the present invention are as follows.

In order for the clutch to engage smoothly, it is desirable that the clutch has a wet clutch configuration.
Further, each operating part in these clutches requires lubricating oil for its operation.

For this reason, in the invention of the third and youngest brother, pressure oil is jetted from one hydraulic pipe line, which has a constant working oil pressure, to each operating part of the clutch via the other throttle.

As is clear from the above description, the effects of the third invention are as follows.

Since the structure is such that the pressure oil in one hydraulic pipe line, which always has a constant operating pressure, is used to spray the hydraulic oil into the clutch part, it is necessary to provide a new hydraulic source with a constant oil pressure for this injection. It is something that has become something that does not exist.

As a result, these clutches enable smooth engagement of the clutches with a constant amount of lubricant oil jetted from one hydraulic pipe, without the need to newly provide a hydraulic source with a constant oil pressure for the jetting. Since lubricating oil cools the clutch surface, it is possible to configure large clutches that transmit large torques used in trucks, etc., and lubricates the eyes, clutches, and other operating parts of these clutches using the federal oil amount. It is possible to do this by.

Further, in contrast to the first invention of the present invention, the fourth invention of the present invention is as follows.

In addition to the first aspect of the present invention, the clutch includes a spring that applies a biasing force in a direction to separate one clutch plate from another clutch plate, and the hydraulic switching valve controls the hydraulic pressure of the other clutch before starting the circuit. The pipe is configured to communicate with a reservoir, and an unload valve is provided between the hydraulic power source and one of the hydraulic pipes, and the unload valve is configured to communicate between the hydraulic power source and the one hydraulic pipe before starting the engine. The oil pressure source and the one hydraulic pipe are connected to each other, and after the engine is started, communication between the hydraulic power source and the one hydraulic pipe is closed.

” - The effects of the fourth invention in the present invention are as follows.

Before starting the engine, the hydraulic switching valve communicates the other hydraulic line with the reservoir, and in this state, the spring in the clutch urges the other clutch plate to separate from the clutch plate, so the other hydraulic line is connected to the reservoir. The hydraulic fluid in the hydraulic pipe is discharged to the reservoir via the hydraulic switching valve,
The clutch is in a disengaged state.

In addition, in this state before starting the engine, the unload valve communicates between the hydraulic pressure source and one of the hydraulic pipes, so even if the engine is started and hydraulic pressure is generated in the oil pressure source, the The working oil pressure is equal to the working oil pressure in one of the hydraulic lines.

In this state, as explained in the first invention, the hydraulic pressure in the hydraulic source is lower than the predetermined hydraulic pressure (pd), so the hydraulic switching valve connects the other hydraulic pipe to the reservoir. continues to communicate.

Therefore, pressure oil is sent to the hydraulic actuator from one side of the hydraulic pipe, the clutch remains disengaged, and the engine is started without transmitting power from the engine to the drive wheels. It is something that can be done.

Furthermore, after the engine has been warmed up after the engine is started, if the communication between the hydraulic pressure source and the first hydraulic line is closed by the unload valve, when the automobile described in the invention of f51 starts. This will be the first posture of

The effects of the fourth invention described above are as follows.

BACKGROUND ART When starting an engine in an automobile, the flow of mechanical power from the engine to the drive wheels must be disconnected before the engine is started, otherwise the automobile will start at the same time as the engine starts.

Therefore, in the first aspect of the present invention described above, in order to solve such a problem that in a normal automobile, the engine is started after the driver depresses the clutch pedal and disengages the clutch, the engine is started in this state. Before starting the engine, the driver sets the gears in the transmission to the neutral position to disconnect the engine from the drive wheels, and in this state, the engine can be started.・However, according to the fourth invention, it is possible to set the neutral position of the transmission without having to perform the troublesome operation of setting the neutral position.
Before starting the engine, the clutch can be disengaged by communicating the unload valve with the hydraulic power source and one of the hydraulic lines, so the engine can be easily and clearly prepared to start. Therefore, there is no need to worry about misunderstanding the neutral position of the transmission and starting the car at the same time as the engine starts.

Hereinafter, the present invention will be explained based on Examples.

FIG. 1 is a system diagram showing a clutch control circuit as an embodiment of the present invention.

The clutch plate 1c is fitted onto the engine shaft la, which is the drive shaft of the engine, and the clutch plate 1d, which selectively engages and disengages with the clutch plate IC, is axially connected to the input shaft 1b of the transmission (not shown). Clutch plate 1d
The piston 1g interlocked with the hydraulic actuator 2 is fitted into the cylinder of the hydraulic actuator 2 so as to be able to slide in the axial direction, and the clutch plate 1d is biased to the right by the spring lh. It makes up the chill.

The hydraulic pump 5 driven by the engine passes the suction pipe 5b to the reservoir 5d, and the hydraulic pipe 5a, which serves as the discharge pipe of the oil r+pump 5 and serves as the hydraulic pressure source of the circuit, has a back pressure valve 8 on one side and a hydraulic pressure switching valve on the other hand. 3 and the displacement chamber if in the hydraulic actuator 2 via the hydraulic pipe 3a,
On the other hand, it is connected to the displacement chamber 1e in the hydraulic actuator 2 via the pressure control circuit 4 and the hydraulic pipe 7a.

Further, the hydraulic pressure V7a is connected to the reservoir 5d via the back pressure valve 7, and an unload valve 6 is interposed between the hydraulic pipe 5a and the hydraulic pipe 7a. is oil hajil)! ! -5a, and the external pilot pipe 7b in the hydraulic switching valve 3 communicates with the hydraulic pipe 7a.

The hydraulic switching valve 3 changes its 9J switching position to 3A when the pilot hydraulic pressure in the pilot pipe 5c is higher than the hydraulic pressure that is mutually exclusive to the pilot hydraulic pressure in the pilot pipe 7b and the spring biasing force installed in the hydraulic switching valve 3. , and in the opposite state, the switching position is set to 3B.

Therefore, before the engine is started, when the pilot oil pressure in both the pilot pipes 5C and 7b is zero, the biasing force of the spring installed in the hydraulic switching valve 3 causes the hydraulic switching valve 3 to switch. position 3
It is set to B.

The unload valve 6 sets its switching position to 6A when no signal pressure is applied to the input part 6a, and sets its switching position to 6B when signal pressure is applied to the input part 6a. The structure is as follows.

The pressure control circuit 4 includes a relief valve 4A and a relief valve 4A.
It consists of a pilot part 4C that sets the pilot pressure of the pilot part 4C, and a solenoid 4B that operates the pilot part 4C. The relationship is such that the value increases in proportion to the depression position.

The operation of the configuration shown in FIG. 1 above will be explained below using the characteristic diagram shown in FIG. 2.

Before starting the engine in a car,
As described above, since pilot hydraulic pressure is not generated in both the pilot pipes 5C and 7b, the hydraulic pressure switching valve 3 has its switching position set to 3B.

Also, in the hydraulic actuator 2 before starting the engine, since hydraulic pressure is not generated in both the displacement chambers 1e and if, the spring lh is
g to the right to separate the clutch plate 1d from the clutch plate 1c.

Also, at this time, due to the movement of the piston Ig to the right,
The hydraulic oil in the displacement chamber if is discharged from the hydraulic pipe 3a to the reservoir 5d via the hydraulic switching valve 3.

Also, before starting the engine, the unload valve 6
Since no signal pressure is applied to the input section 6a, the unloading spout t6 remains set at the switching position 6A.

When the driver starts the engine of the car in this state, the hydraulic pump 5 is also driven at the same time as the engine starts, and as a result, the hydraulic pump 5 pumps up hydraulic oil from the reservoir 7<5d through the suction pipe 5b. The pumped hydraulic oil is pressurized by the hydraulic pump 5 and discharged into the hydraulic pipe 5a.

In addition, in this state, the unload valve 6 is set to the switching position 6.
A is set to communicate the hydraulic pressure 15a and the hydraulic pipe 7a, and the working pressures of both the hydraulic pipe 5a and the hydraulic pipe 7a are made equal.

Therefore, the pilot pressures of both the pilot pipe 5c and the pilot pipe 7b become equal, and as a result, in the hydraulic switching valve 3, the sum of the operating force due to the pilot pressure of the pyro-soto pipe 7b and the internal spring biasing force is the pilot pressure. Overcoming the operating force due to the pilot pressure of pipe 5C.

The switching position remains set at 3B, and the hydraulic pipe 3a remains connected to the reservoir 5d via the hydraulic switching valve 3.

Therefore, in this state, the displacement chamber if is opened to the reservoir 5d and becomes atmospheric pressure, and the pressure oil in the hydraulic pipe 7a under constant pressure flows into the displacement chamber 1e and presses the piston 1g to the right. Leave it alone, clutch
is still in a state of withdrawal 1! : It becomes.

In this state, when the engine has been warmed up and the vehicle is ready to start, the driver depresses a clutch pedal (not shown) to set the gear ratio in the transmission to a required position.

When the clutch pedal is depressed in this way, in conjunction with the depression, the radio waves to the solenoid 4B in the pressure control circuit 4 are set to the maximum value, and the pyro- and to-pressures in the pilot section 4C are set to the minimum value. be done.

With this clutch pedal depressed, the driver completes the setting of the gear ratio described above, and then
The operator sends a pressure signal to the human power section 6a of the unload valve 6, thereby setting the unload valve 6 to the switching position fi6B.

As a result, the unload valve 6 of the hydraulic pipe 5a and the hydraulic pipe 7a
The communication via the hydraulic pipe 5a as a hydraulic source is closed.
The only circuit through which pressure oil flows from the side to the hydraulic pipe 7a side is through the pressure control circuit 4.

The above-mentioned state set in this way is the initial stage at which the vehicle can be started.

From this initial stage, when the driver releases the clutch pedal, the current value in the solenoid 4B decreases in proportion to the amount of release, and the pilot pressure in the pilot section 4C is inversely proportional to the decrease in current value. It continues to increase.

In other words, the work in the hydraulic pipe 5a! The F11 oil pressure increases in inverse proportion to the decrease in the electric current 9Q i in the solenoid 4B, as shown in the characteristic p5a shown in FIG.

In addition, the horizontal axis i in FIG. 2 shows the current learned by the solenoid 4B, and the inter-axis P shows the respective working oil pressures in each oil If: pipes 3a, 5a and 7a.

On the other hand, due to the presence of the back pressure valve 7, the characteristic of the hydraulic pressure in the hydraulic pipe 7a is such that the hydraulic pressure is always constant regardless of the current value, as shown in p7a.

In this relationship, when the clutch pedal is released, the current i in the solenoid 4B will eventually become 1=i
In this case, the hydraulic pressure switching valve 3 is operated by the pilot pressure pd of the pilot pipe 5C. The force is in a relationship that is higher than the sum of the operating force due to the pilot pressure of the pilot pipe 7b and the biasing force of the spring inside the hydraulic switching valve 3. Therefore, in this state,
The pilot pressure pd in the pilot pipe 5C is determined by setting the hydraulic switching valve 3 to the switching position 3A and switching the hydraulic pipe 5a to the hydraulic pipe 3a.
It is in a state where it is connected to.

When the oil country pipe 5a and the hydraulic pipe 3a are in communication with each other in this way, the working pressure in the hydraulic pipe 5a is higher than the working pressure in the hydraulic pipe 7a, so the hydraulic pipe 5a
A portion of the pressure oil in the back pressure valve 8. It is in a state where it is forced to be fed to the displacement chamber 1f via the hydraulic pressure switching valve 3 and the hydraulic pipe 3a.

However, in this case, since the flow of pressure oil from the hydraulic pipe 5a to the hydraulic pipe 3a is through the back pressure valve 8, a certain pressure loss occurs in the back pressure valve 8, and as a result, the pressure oil flows from the hydraulic pipe 3a to the hydraulic pipe 3a. The working oil pressure at is the working oil pressure obtained by subtracting the differential pressure dp corresponding to the pressure loss from the working oil pressure in the hydraulic pipe 5a, and the characteristics of the working oil pressure are as shown at p3a in FIG. 2.

Therefore, the value of 1=ic mentioned above means that when the hydraulic switching valve 3 is set to the switching position 3A, the working pressure in the hydraulic pipe 3a is equal to or slightly larger than the working pressure in the hydraulic pipe 7a. If the current is set to a value such that when the clutch hot pedal is released, the hydraulic switching valve 3 is switched to the switching position H3A at i=ic, so that the pressure oil in the hydraulic pipe 5a is pumped to the hydraulic pressure 113a. Even if this happens, the working oil pressure on the hydraulic pipe 7a side and the hydraulic pipe 3a side are almost equal, so the hydraulic pressure on the hydraulic pipe 3a side is almost equal.
The pressure oil that is force-fed from a to the displacement chamber lf begins to smoothly flow into the displacement chamber lf.

In this manner, when the pressure oil starts to flow from the hydraulic pipe 3a into the displacement chamber 1f, the driver further releases the clutch pedal, thereby causing the working pressure in the hydraulic pipe 3a to change as indicated by the arrow a in FIG. As it moves up y, the pressure oil on the side of the hydraulic pipe 3a flows into the displacement chamber if lA
The hydraulic fluid in the displacement chamber 1e continues to flow through the hydraulic pipe 7.
a and the back pressure valve 7 or the throttle passage 10 to the reservoir 5d or each sliding part of the clutch 1, thereby pushing the piston 1g to the left, and the piston 1g pushes the clutch plate 1d against the clutch plate IC. It will be engaged with.

Historically, in the above operation, pressure oil is spouted from the hydraulic pipe 7a to the throttle channel 10, so that
The spouted oil makes the engagement of the clutch even smoother, and the spouted oil also makes the clutches lc and ld fl
) Cools the heat generated due to the relative slippage occurring in the clutch 1, and at the same time, the ejected oil lubricates each sliding part in the clutch 1.

As mentioned above, in the operation shown in FIG. 2, region I is the range in which clutch 1 is engaged, and region C is the range in which clutch I is disengaged.

In the clutch operation described above, when depressing the clutch to change the gears in the transmission and disengaging the clutch l, there must be no drag torque on the clutch l, and the clutch plate 1d must be It must be completely separated from the IC.

On the other hand, when starting a car with the clutch in the opposite position! The Kula Sochi pedal must be operated in such a way as to create a drag torque on clutch 1.

To ensure that such operations are possible, when operating the clutch to change gears in the transmission, depress the clutch Φ pedal until the current (+6j) becomes greater than ic, and as described above, , the hydraulic switching valve 3 is set to the switching position 3B, and the hydraulic oil in the displacement chamber 1f is instantly released to the reservoir 7 through the hydraulic switching valve 3, and as a result, the clutch 1 is instantly and reliably disengaged. It will be.

Furthermore, when starting the 1'1 drive with the clutch in the anti-clutch position, the clutch pedal should be operated so that the current value is within the range e in FIG.

In addition, in the above embodiment, the hydraulic pipe 3a in FIG.
A throttle flow path 9 shown by a phantom line between and the reservoir 5d
By interposing the conduit 3C having the above-described structure, it becomes possible to more easily transmit the torque in the clutch when the clutch is engaged in the above embodiment.

That is, the effects when the throttle fluid path 9 is interposed between the hydraulic pipe 3a and the reservoir 5d are as follows.

From the hydraulic pipe 5a to the back pressure valve 8, the hydraulic switching valve 3 and the hydraulic pipe 3
After the pressure oil is fed to the displacement chamber if via a and the piston Ig starts to engage the clutch l, the leftward movement of the piston Ig becomes almost zero, and the pressure oil is transferred to the displacement chamber if. The inflow of will be almost zero.

In such a case, if the configuration is such that the throttle channel 9 is not interposed between the hydraulic pipe 3a and the reservoir 5d, the flow of pressure oil into the displacement chamber if is almost zero, as described above. After that, the flow of pressure oil from the side of the hydraulic pipe 5a to the side of the hydraulic pipe 3a almost stops t-L, the differential pressure dp no longer occurs in the back pressure valve 8, and the working oil pressure and the oil pressure in the hydraulic pipe 3a stop. The working oil pressure in the pipe 5a becomes equal.

Such a phenomenon occurs in the hydraulic pipe 3a)
11, but when clutch 1 starts engaging, it is the same as 11! ? Then, the characteristic p3a in FIG. 2 shifts to the characteristic p5a, and as a result, the hydraulic pressure of the displacement chamber 1f rapidly decreases.

That is, when clutch l starts to engage, the pressing force of piston 1g increases rapidly, and as a result, clutch l
The transmitted torque suddenly increases.

This may result in engine knocking if the i1 driver does not operate the clutch delicately when the clutch 1 is engaged.

However, if the throttle flow path 9 is interposed between the hydraulic pipe 3a and the reservoir z<5d, even if the pressure oil flows into the displacement chamber 1f or stops, the back pressure valve 8 There exists a flow of pressure oil from the hydraulic pipe 5a to the reservoir 5d via the back pressure valve 8, the hydraulic switching valve 3, the hydraulic pressure v3a, and the throttle channel 9.

Therefore, the back pressure valve 8 always has a differential pressure cip from the flow.
occurs, and the operating pressure of the hydraulic pipe 3a remains at p in FIG. 2 even after the flow of pressure oil into the displacement chamber if becomes almost zero.
Maintain the characteristics of 3a.

In this way, when the throttle flow path 9 is interposed between the hydraulic pipe 3a and the reservoir 5d, as described above, when the clutch is engaged, the hydraulic pressure characteristic of the hydraulic pipe 3a is changed to p3a in FIG.
There is no transition from p5a to p5a, and the torque change in the clutch can be smoothly performed in proportion to the return of clutch operation.

Further, the pipe line 3C having the throttle flow passage 9 is connected to the hydraulic pipe 3a and the hydraulic pipe 7, as shown by the virtual line in FIG.
A configuration may also be adopted in which a throttle flow path 9a is interposed between the flow path 9a and the flow path 9a.

In that case, the hydraulic oil in the hydraulic pipe 3a can be spouted to the clutch l via the throttle channel 9a, the hydraulic pipe 7a, and the throttle channel 10, and the spouted hydraulic fluid can be discharged to the reservoir 5d. It is from.

Further, in the above embodiment, the pressure control circuit 4 controls the working oil pressure in the hydraulic pipe 5a by current control, but this is in conjunction with the clutch pedal and controls the pressure control circuit 4 by other signals such as air pressure. It may also be controlled.

In the above embodiment, the current control in the solenoid 4B is performed in conjunction with the Craftch pedal, but the current control is performed in conjunction with gear switching in the transmission, accelerator pedal operation, etc., and the current control is performed in conjunction with the clutch pedal. It may also be used for so-called two-pedal control.

In addition, as mentioned above, the unload valve 6 is used to disengage the clutch l when the engine is started so that the car does not start at the same time as the engine starts. To keep it disconnected, the gears in the transmission can also be set in a neutral position and started. Therefore, as the basis of the present invention, the unload valve 6 is not necessarily required.

However, due to the presence of the unload valve 6, the flow of power from the engine side to the output side is ensured when the engine is started, and there is no need to operate the transmission lever to set it in the wrong neutral position, making it easy to operate the clutch 1. It can be separated into two parts.

Further, in the above embodiment, the switching position of the unload valve 6 is set to 6A when no signal is sent to the input section 6a before starting the engine,
The switching position is set to 6B when a signal is being sent to the input unit 6a after the engine has started, but this means that the signal is sent to the input unit 6a before the engine is started. The switching position may be set to 6A, and the signal to the input section 6a may be eliminated after the engine is started, thereby setting the switching position to 6B.

In short, it is sufficient that the unload valve is set to the switching position 6A before the engine is started, and that the unload valve is set to the switching position 6B after the engine is started.
- It will be easily understood from the above explanation.

Further, the unload valve 6 is provided between the hydraulic pipe 5a and the hydraulic pipe 7a, but the method of setting the unload valve 6 between the hydraulic pressure '1I5a and the reservoir 5d and setting its switching position to 6B is , a spring may be installed inside the unload valve 6, and the switching position 6B may be set by the biasing force of the spring.

[Brief explanation of the drawing]

Fig. 1 shows a system diagram of a clutch control circuit as an embodiment of the present invention, and Fig. 2 shows the respective working oil pressures in the hydraulic pipe 3a, the hydraulic pipe 5a, and the extraction pipe 7a in Fig. 1. characteristic p3a,
p5a and p7a are shown. The symbols used in the examples are as follows: 1: Clutch la: engine shaft, lb = input shaft. lc and ld: clutch, le and 1f: displacement chamber, 1g: piston, lh spring. 2: Hydraulic actuator 3: Hydraulic switching valves 3A and 3B; switching position, 3a: Hydraulic pipe, 3b: Pipe line. 4: Pressure control circuit 4A: Relief valve, 4B: Solenoid, 4C: Pilot section. 5: Hydraulic pump 5a: Hydraulic pipe, 5b: Suction pipe, 5C: Pilot pipe, 5d: Reservoir. 6: Unload valves 6A and 6B: 4/J exchange position, 6a: Input section. 7 and 8: Back pressure valve 7a: Hydraulic pipe, 7b: Pilot pipe. 9 and lO: throttle channel. Patent applicant Sanwa Seiki Co., Ltd. Representative Etsushi Nishikai Figure 1 Figure 2

Claims (1)

[Claims] 1. The clutch includes a clutch plate that is interlocked with the engine shaft, and another clutch plate that selectively engages and disengages from the clutch plate and is interlocked with the input shaft of the transmission. 1. The hydraulic actuator operates the other clutch plates, and the hydraulic actuator has the following functions: a: Pressure oil flowing from a single-force hydraulic conduit causes ■ 1J
b: The clutch plate and the clutch plate on the side are brought into engagement by the pressure oil flowing from the other hydraulic pipe. , In the configuration of 1- below, which has a configuration consisting of the above a and b, C: The one hydraulic pipe line is such that pressure oil from a hydraulic source communicating with a discharge hole of a hydraulic pump is passed through a pressure control circuit. inflow,
11, a part of the inflowing pressure oil is discharged to a reservoir via one of the back pressure valves, and d: the pressure control circuit connects the hydraulic pressure from the hydraulic power source to the hydraulic pressure line The hydraulic pressure value in the hydraulic pressure source is changed by changing the pressure oil output (1), and the change in the pressure oil output (-11+) is controlled by an external signal. None, e; the other hydraulic line is connected to the hydraulic pressure source via a hydraulic switching valve and another back pressure valve; When the working oil pressure is below a predetermined working oil pressure (PD) which is higher than the working oil pressure in the pipe, the hydraulic pressure source communicates with the other hydraulic pipe through the back pressure valve on the side. When the hydraulic pressure in the hydraulic pressure source 11j is lower than the predetermined hydraulic pressure (PD), the other hydraulic pipe line is communicated with the reservoir. A flanch control circuit characterized by comprising the following two configurations. 2. The clutch includes a clutch plate that is interlocked with the engine shaft, another clutch plate that selectively engages and disengages from the clutch plate and is interlocked with the input shaft of the transmission, and the other clutch. It consists of a hydraulic actuator that operates the plate,
The hydraulic actuator disengages the clutch plate from the clutch plate i (i) by means of pressure oil flowing from one hydraulic pipe, and b: from the other hydraulic pipe. In the above structure consisting of a and b, the clutch plate and the other clutch plate of 1 inch are engaged by the inflowing pressure oil, c: +iii one of the hydraulic pipes is , Pressure oil from a hydraulic source communicating with the discharge hole of the hydraulic pump flows in through the pressure control circuit, and a part of the pressure oil that flows into the pump is discharged to the reservoir 7S through one back pressure valve. d: The pressure control circuit changes the value of the hydraulic pressure in the hydraulic source by changing the amount of restriction of pressure oil flowing out from the hydraulic source to the one hydraulic pipe line. The change in the amount of pressure oil flowing out is controlled by an external signal, e: iii. The other hydraulic pipe line is connected to the hydraulic pressure source via a hydraulic switching valve and another back pressure valve, The hydraulic switching valve is configured such that when the hydraulic pressure in the hydraulic pressure source is equal to or higher than a predetermined hydraulic pressure (PD) higher than the hydraulic pressure in the one hydraulic line, the hydraulic pressure source switches to the other back pressure valve. is set to be in communication with the other hydraulic pipe line via
d) When the working oil pressure is lower than I11!, the other hydraulic pressure line is used as a reservoir. Let it pass. g: A flanch having the configuration as described in 1- below, wherein the other hydraulic pipe line is connected to the reservoir via a pipe line that accommodates a throttle flow path. Control 1D circuit. 3. The clutch consists of a clutch plate that is interlocked with the engine shaft, another clutch device that engages and disengages like the clutch plate described in +iii and is interlocked with the input shaft of the transmission, and ti.
(ii) a hydraulic actuator for operating another clutch plate; and (b) engaging the clutch device and the other clutch plate by means of pressure oil flowing from an externally applied hydraulic pressure pipe. In the configuration of -1- below, c: +JiJ One hydraulic pipe receives pressurized oil from a hydraulic source communicating with the discharge hole of the hydraulic pump through the pressure control circuit, and A portion of the oil is discharged into a reservoir via one of the back pressure valves, and d: the pressure control circuit changes the throttling point of pressure oil outflow from the hydraulic power source to the one hydraulic pipe line. By changing the value of the hydraulic pressure in the hydraulic pressure source +if, the change in the pressure oil outflow lit is operated by an external signal, e: the other hydraulic pipe line is f: the hydraulic switching valve is connected to the hydraulic power source via a hydraulic switching valve and another back pressure valve; When the working oil pressure in the hydraulic pressure is equal to or higher than a predetermined working oil pressure (PD) which is higher than the working oil pressure in the one hydraulic line, the The other hydraulic pipe line is set to be in communication with the reservoir, and if the working oil pressure in the hydraulic pressure source is lower than the predetermined working oil pressure (PD), the other hydraulic pipe line is communicated with the reservoir. g: The one hydraulic pipe line jets pressure oil toward each actuating part of the clutch through the other throttle flow path. clutch control circuit. 4. The clutch includes a clutch plate that is interlocked with the engine shaft, another clutch plate that selectively engages and disengages from the clutch plate and is interlocked with the input shaft of the transmission, and the other clutch plate. It is composed of the above-mentioned elements, including a hydraulic actuator to be operated, and a spring that applies a biasing force in the direction of disengaging the clutch plate and the other clutch plate, and the hydraulic actuator has the following elements: a. The clutch plate and the other clutch plate are disengaged by the pressure oil flowing from the other hydraulic pipe, and the clutch plate and the other clutch plate are engaged by the pressure oil flowing from the other hydraulic pipe. In the following configuration, which has a configuration consisting of a and b in -1- below, C: One of the hydraulic pipes receives pressure from a hydraulic source communicating with a discharge hole of a hydraulic pump. Oil enters through the pressure control circuit,
A part of the inflowing pressure oil is discharged to a reservoir via one of the back pressure valves, and d: The pressure control circuit is configured to supply pressure oil from the hydraulic source to the one hydraulic pipe line. The hydraulic pressure value in the hydraulic pressure source is changed by changing the amount of fluid outflow throttled, and the change in the pressure oil outflow amount is controlled by an external signal, e: the other hydraulic pressure. The pipeline is connected to the hydraulic pressure source via a hydraulic switching valve and another back pressure valve, and the hydraulic switching valve is configured such that the hydraulic pressure in the hydraulic source is higher than the hydraulic pressure in the one hydraulic pipeline. When the hydraulic pressure is equal to or higher than the hydraulic pressure (pd) of the hydraulic pressure, the hydraulic pressure source is set to communicate with the other hydraulic pipe via the other back pressure valve, and the hydraulic pressure of the hydraulic source is set to the hydraulic pressure of Predetermined working oil pressure (p
d) When the working pressure is lower than d), the other hydraulic pipe is connected to the reservoir. h: The unload valve connects the hydraulic power source and the one hydraulic pipe before starting the engine, and connects the hydraulic power source and the one hydraulic pipe after starting the engine. A clutch control circuit characterized in that it is configured as described above and closes communication between the passages.