JPH0155324B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a control device for a motor vehicle clutch. More particularly, the present invention relates to an apparatus for automatically controlling a clutch in response to changes in engine speed.

In automobiles, the technology for automatically controlling the engaged state of the clutch by controlling the fluid pressure for operating the clutch so that the stroke position of the clutch operating member is proportional to the engine speed was developed in Japanese Patent Publication No. 1973-
Already proposed by No. 48694. This known device not only controls the clutch in response to engine speed, but also detects engine deceleration and responds by phase-advancing changes in fluid pressure relative to changes in engine speed. This eliminates the delay in actuator operation for clutch operation, and prevents the engine from stopping or racing when starting suddenly. However, this known method basically makes the stroke of the clutch operating member proportional to the engine speed, which has the disadvantage that the engagement state of the clutch is influenced by clutch wear or clutch temperature.

In a separate application, the present applicant has proposed a clutch control device that allows clutch engagement to be most adapted to the load condition of the engine, compared to such known clutch control devices. This clutch control device includes a discrimination circuit that detects a negative rate of change in the engine speed, and when the discrimination circuit detects a negative rate of change in the engine speed, the clutch connecting direction of the clutch engagement operation member is adjusted. and control means for stopping the operation and holding it in the stopped position. Therefore, when the engine speed starts to drop due to too much load being applied to the engine while the clutch is engaged, this drop is detected by the discrimination circuit and the clutch is engaged, taking into account factors such as clutch temperature or clutch wear. This has the advantage that it acts on the actuator as a feedback signal indicating the state, interrupts the clutch engagement operation, maintains the half-clutch state for a short time, and prevents the engine speed from dropping excessively. However, in this clutch control device, the clutch's intermittent operating member is operated at a constant speed regardless of the rate of increase in engine speed.
For example, since the clutch is engaged before the engine speed has sufficiently increased, it is unable to follow the increase in load, and the clutch engagement is frequently interrupted due to a drop in the engine speed. The number of rotations decreases and increases repeatedly. As a result, the vehicle may not start smoothly and may cause discomfort to the driver.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a clutch control device that can adjust the operating speed of an actuator and, in turn, the operating speed of an on/off operating member of a clutch in accordance with the rate of increase or change in engine speed.

The clutch control device for an automobile according to the present invention includes an actuator that operates a clutch engagement operation member provided between an engine output shaft and a transmission input shaft in a clutch connecting direction, and an actuator that detects a rate of change in engine speed. and determining means for generating an output according to the magnitude and sign of the rate of change, and the actuator performs the operation when receiving an output from the determining means indicating that the rate of change in engine speed is negative. The operation of the member in the clutch connecting direction is stopped and held at the stop position, and the operating member is moved in the clutch connecting direction when an output indicating that the rate of change in engine speed is positive is received from the determining means. The present invention further provides a clutch control device for an automobile comprising a control means for receiving the output of the determining means and adjusting the operating speed of the actuator in the clutch connecting direction in accordance with the magnitude of the rate of change in engine speed. Features.

According to the automobile clutch control device of the present invention having such a structure, the differential circuit and the first
Since the control means operates the actuator and, in turn, the clutch switching operation member at a speed that corresponds to the rate of change or increase in engine speed.
For example, when the rate of increase in engine speed is low,
The clutch is engaged slowly, so the engine speed does not drop frequently and the engine starts smoothly. Furthermore, according to the clutch control device of the present invention, when the engine speed begins to drop due to an excessive load being applied to the engine during clutch engagement, this drop is detected by the discrimination circuit, and the clutch temperature or clutch A feedback signal that takes wear and the like into consideration is applied to the actuator via the second control means, the clutch engagement operation is interrupted, and the half-clutch state is maintained for a short time to prevent the engine speed from decreasing excessively. .

In a preferred embodiment of the present invention, the control means is preferably constituted by a valve means for regulating the flow rate of the working fluid supplied to the actuator.

DESCRIPTION OF THE PREFERRED EMBODIMENTS A clutch control device for an automobile according to a preferred embodiment of the present invention will be described below with reference to the accompanying drawings.

First, in FIG. 1, the output shaft 1a of the engine 1
is the input shaft 3 of the transmission 3 via the clutch mechanism 2.
a, and the clutch mechanism 2
has a clutch operating member 4 for controlling this on and off. When the lower end of the clutch operating member 4 is moved to the right in the figure, the clutch is disengaged.
The clutch is configured to engage when moved to the left. The lower end of the operating member 4 is connected to a diaphragm device 5 via an actuating rod 6. The diaphragm device 5 has a negative pressure chamber 5a, and when negative pressure is introduced into the negative pressure chamber 5a, the lower end of the operating member 4 is pulled to the right to shut off the clutch mechanism. Negative pressure chamber 5
a is connected by a negative pressure passage 7 via a check valve 8 to the downstream side of the throttle valve 9 of the intake passage 1a of the engine. A negative pressure tank 10 is provided in the negative pressure passage 7, and negative pressure is introduced into the negative pressure chamber 5a through a control valve 11,
The holding valve 12 , the orifice 14 disposed in the control passage 13 that communicates the holding valve 12 with the negative pressure chamber 5 a of the diaphragm device 5 , and the orifice 1
It is controlled by a speed control valve 16 disposed in a bypass passage 15 that bypasses the speed control valve 4. That is, the control valve 11 is an electromagnetic valve that switches between communicating the negative pressure chamber 5a with the negative pressure passage 7 and opening it to the atmosphere, and when the holding valve 12 is open, the control valve 11 is energized. Then, negative pressure chamber 5
a is connected to the negative pressure passage 7, and the diaphragm device 5
is activated, and the clutch mechanism 2 is disconnected. The holding valve 12 is a cutoff valve that closes the control passage 13 in an excited state, cuts off the introduction of working fluid into the negative pressure chamber 5a, and maintains the pressure in the negative pressure chamber 5a at the current value. The orifice 14 is for maintaining the introduction speed of negative pressure or atmospheric air into the negative pressure chamber 5a at a low constant value, and is used for controlling the speed control valve 1.
6 opens the passage 1 together with the passage 13.
5 also introduces negative pressure or atmospheric air into the negative pressure chamber 5a to speed up the introduction speed.

A control circuit 17 is provided to operate the control valve 11, the holding valve 12, and the speed control valve 16. A clutch switch 20 that operates when the hand is released, a neutral switch 21 that operates when the transmission is in a position other than the neutral position, an accelerator pedal switch 22 that operates when the accelerator pedal is depressed, a vehicle speed pulse generator 23 that detects vehicle speed, and Inputs a signal from a pulse generator 24 that detects the rotation speed of the clutch driven side,
The output is given to the servo amplifier 25, and the servo amplifier 2
5 generate outputs that are applied to the control valve 11, holding valve 12, and speed control valve 16, respectively.

FIG. 2 shows details of the control circuit 17, in which the output of the rotational speed pulse generator 18 is applied to a frequency/voltage converter 26, which generates an output e ₁ . The output of the converter 26 is input to a differentiating circuit 27, which generates an output e _d . This output e _d is provided to a comparator 28 and compared with zero voltage to determine the engine speed change rate. It produces a positive output e _a when it is positive and zero when it is negative. The output e _a of the comparator 28 is input to an exclusive OR circuit 29 . Exclusive OR circuit 2
9, a signal from the accelerator pedal switch 22 is separately input.

The output of the pulse generator 24 that detects the number of rotations on the driven side of the clutch is sent to the frequency/voltage converter 3.
0 and converter 30 produces an output e ₂ .
The output e ₂ is input to a differential amplifier 31 on the one hand and to a differential amplifier 32 on the other hand. Differential amplifier 3
The output e ₁ from the converter 26 is also input to 1 and 32, and this output e ₁ and the output e ₂ from the converter 30 are compared, and the outputs e ₀₁ = k (e ₂ − e ₁ ) and e ₀₂
= k(e ₁ −e ₂ ) is generated. The output e ₀₁ from the differential amplifier 31 is input to a comparator 33 and compared with a reference voltage to generate a binary output. Similarly, the output e ₀₂ from differential amplifier 32 is input to comparator 34 and compared with a reference voltage to generate a binary output. The outputs from these comparators 33 and 34 are respectively
It is input to the OR circuit 37. The output of the OR circuit 37 indicates whether the rotation speeds on the driving side and driven side of the clutch mechanism are the same, and is a low level when the clutch is fully engaged and a high level when the clutch is incompletely engaged. be.

The output from the vehicle speed pulse generator 23 is input to a frequency/voltage converter 39, and the converter 39 generates a voltage signal e ₀₃ according to the vehicle speed. this signal
e ₀₃ is input to the comparator 40 and compared with the reference voltage V _r1 , and when the vehicle speed is above a certain value K2, a high level output is generated, and this output is input to the OR circuit 41. A signal from the accelerator pedal switch 22 is also input to the OR circuit 41, and the output of the OR circuit 41 is input to the AND circuit 42. AND circuit 4
2 also receives signals from a clutch switch 20 and a neutral switch 21.

Exclusive OR circuit 29 from comparator 28
The signal input to the circuit 29 indicates the rate of change in the engine speed, and a low level signal is applied to the circuit 29 when the rate of change in the engine speed is negative, and a high level signal when it is positive. When the accelerator pedal is depressed and the engine speed exhibits a negative rate of change, a high level output is generated from circuit 29. The output of the exclusive OR circuit 29,
The outputs from the OR circuit 37 are respectively given to the NAND circuit 45, and the output of the NAND circuit 45 is
It is applied to the AND circuit 46. The output of the AND circuit 42 indicates whether the vehicle speed is above a certain value, and is input to the AND circuit 46. AND circuit 46
The output is input to the base of the switching transistor 49, and controls the excitation of the solenoid 11a of the control valve 11. When the solenoid 11a is energized, the negative pressure chamber 5a of the diaphragm device 5 is opened to the atmosphere, allowing the clutch mechanism to be connected.

The output of the exclusive OR circuit 29 and the OR
The output from the circuit 37 and the output from the AND circuit 42 are respectively input to the AND circuit 35,
The output of the AND circuit 35 is applied to the base of a switching transistor 36. transistor 36
is for controlling the excitation of the solenoid 12a of the holding valve 12. The holding valve 12 holds the negative pressure chamber 5a of the diaphragm device 5 in a closed state when the solenoid 12a thereof is excited.

The output e _d of the differentiating circuit 27 is also connected to the inverting amplifier 50
This inverted output e _d is given to the comparator 51 and compared with the reference voltage Vr ₃ , and the differential signal that is the output e _d , that is, the rate of change of the engine speed, is set to a predetermined value K1. A positive signal is output when the value is above a predetermined value, and a zero signal is output when the value is less than a predetermined value. Further, the output e ₀₃ of the converter 39 is input to the comparator 28,
compared with the reference voltage Vr ₂ which is greater than the reference voltage Vr ₁ ;
When it is large, a high level signal is output, and when it is small, a low level signal is output. The output signal of the comparator 51 is
It is input to one input terminal of the OR circuit 52, and this
The output signal of the comparator 48 is input to the other input terminal of the OR circuit 52. The output terminal of the OR circuit 52 is connected to the base of the switching transistor 53.
Reference numeral 3 operates to open the solenoid 16a of the speed control valve 16 by energizing the solenoid 16a when the output of the OR circuit 52 is at a high level.

The operation of the circuit described above will be explained when the vehicle starts as shown in Fig. 3. When the accelerator pedal is depressed to start, the engine speed changes from the idling speed, for example, as shown by the solid line in Fig. 3a. Suppose it starts to rise. At the same time, accelerator pedal switch 22 is closed and a signal is provided to circuits 29,41. Since the rate of change in the engine speed is positive, the output e _a of the comparator 28 is at a high level, and the exclusive OR circuit 29 outputs a low level signal. At the time of starting, the vehicle speed is less than the predetermined speed, so the AND circuit 42 generates a high level output. Furthermore, since the clutch mechanism 2 has not yet been fully engaged, the OR circuit 37 outputs a high level signal. Under these conditions,
The NAND circuit 45 generates a high level output,
The AND circuit 46 also generates a high level output, and the solenoid 11a of the control valve 11 is energized.
1 is opened to the atmosphere. The AND circuit 35 is
At this time, a low level output is generated and the solenoid 12a of the holding valve 12 is in a demagnetized state. For this reason,
Holding valve 12 is opened. Also, at this time, the output e _d of the differentiating circuit 27 is transferred to the comparator 5 as shown in FIG. 3b.
₁ , the comparator 51 outputs a high level signal. Therefore, the solenoid 16a of the speed control valve 16 is energized,
Speed control valve 16 is opened. In this way, atmospheric air is introduced into the negative pressure chamber 5a of the diaphragm device 5 from the control valve 11, and connection of the clutch is started, but since the speed control valve 16 is open as described above, the atmospheric air is not introduced. This takes place relatively quickly, and therefore the actuation of the clutch actuating member 4 also takes place relatively quickly, as can be seen in FIG. 3c. As the clutch is engaged, the vehicle speed gradually increases as shown by the dashed line in FIG. 3a.

When the engine load increases as the vehicle starts, the increase in engine speed slows down, and if the increase in load is excessive, the engine speed decreases as shown by the solid line in FIG. 3a. This decrease in engine speed is detected as a negative rate of change, taking into account the clutch engagement state that takes into account the clutch temperature and clutch wear, etc., and the output of the comparator 28 becomes a low level, causing the AND circuit 35 to is given a high level signal from the exclusive OR circuit 29. Therefore, the AND circuit 35 generates a high-level output, the transistor 36 becomes conductive, and the solenoid 12a of the holding valve 12 is energized, thereby closing the holding valve 12. Therefore,
The negative pressure chamber 5a of the diaphragm device 5 is closed, and the clutch operating member 4 is stopped from moving to the left and held at that position, and the operation of connecting the clutch mechanism 2 is interrupted. At this time, the output of the NAND circuit 45 becomes a low level, and the output of the AND circuit 46 also becomes a low level, so the solenoid 11a of the control valve 11 is demagnetized, and the circuit leading to the holding valve 12 is connected to the engine intake passage 1a. Ru. When the tendency of the engine speed to decrease stops, the control valve 11 is opened to the atmosphere again, the holding valve 12 is opened, and the clutch connection operation is continued. Once the clutch connection is complete,
Since the output from the OR circuit 37 becomes low level and is given to the AND circuit 35, the holding valve 12
becomes inoperable.

The operation of the circuit when the rate of increase in engine speed is relatively large has been explained above with reference to Fig. 3.
Next, the operation of the circuit when the rate of increase in engine speed is relatively small will be explained with reference to FIG.

When the rate of increase in engine speed is small as shown in FIG. 4a and the output e _d of the differentiator circuit 27 is smaller than the reference voltage Vr ₃ as shown in FIG. 4b, the comparator 5
The output signal of the comparator 48 is at a low level, and since the vehicle speed is slow, the output signal of the comparator 48 is also at a low level. Therefore, since the output signal of the OR circuit 52 becomes low level, the transistor 53 is turned off and the solenoid 16a is demagnetized. Therefore, the speed control valve 16 closes, so the negative pressure chamber 5a
Atmospheric air is introduced only through the passage 13, which is restricted by an orifice 14. Accordingly, as shown in FIG. 4c, the actuation of the clutch actuating member 4 takes place at a relatively low speed, thus allowing the clutch to be engaged slowly. In the connection operation in this case as well, the clutch operation member 4 operates again after a hold period in the same way as shown in FIG. Invert to high level. Therefore, the OR circuit 52 outputs a high level signal, turns on the transistor 53, and turns on the solenoid 16a.
Excite. Therefore, speed control valve 1
6 is opened, atmospheric air is introduced into the negative pressure chamber 5a through both passages 13 and 15. In this way, when the rate of increase in engine speed is small, the clutch is slowly engaged to prevent the engine speed from dropping frequently.

Figure 5 shows an example of a program in which the same effect as described above is achieved by a microcomputer.The clutch switch is turned off when the transmission shift lever is released, and turned on when the hand is applied. By operating as shown in the diagram, you can smoothly engage the clutch without fear of stopping the engine. In the above embodiment, the transmission 3 is operated manually, but the transmission 3 may be of an automatic transmission type through electronic control or the like.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of a clutch control device showing one embodiment of the present invention, FIG. 2 is a system diagram of its control circuit,
3 and 4 are charts showing examples of control at the time of starting, respectively, and FIG. 5 is an example of a program when a microcomputer is used in place of the control circuit shown in FIG. 3. 1...Engine, 2...Clutch mechanism, 3...
Transmission, 4... Clutch operating member, 5... Diaphragm device, 7... Negative pressure passage, 11... Control valve,
12...Holding valve, 16...Speed control valve.

Claims (1)

[Claims] 1. An actuator that operates a clutch engagement operation member provided between an engine output shaft and a transmission input shaft in a clutch connecting direction, and an actuator that detects a rate of change in engine speed and detects the change. and a discrimination means that generates an output according to the magnitude and sign of the ratio,
When the actuator receives an output from the determining means indicating that the rate of change in engine speed is negative, the actuator stops the operation of the operating member in the clutch connecting direction and holds the operating member at the stop position, and In a clutch control device for an automobile configured to move the operating member in a clutch connecting direction when receiving an output indicating that the rate of change in engine speed is positive, the clutch control device for an automobile is configured to move the operating member in a clutch connecting direction when the output from the determining means is received and the engine speed is determined. 1. A clutch control device for an automobile, comprising control means for adjusting the operating speed of the actuator in the clutch connecting direction in accordance with the magnitude of the rate of change of the clutch. 2. The clutch control device for a motor vehicle according to claim 1, wherein said control means is a valve means for regulating the flow rate of the working fluid supplied to said actuator.