JPS624639A - Control method of automatic clutch - Google Patents

Abstract

PURPOSE:To control the gearing rate of a clutch adequately with no complicated driving system, by setting a clutch stroke responding to the engine revolutions and the accelerator pedal stepping rate, and securing the clutch stroke by the force of the driving system. CONSTITUTION:A piston 31 of an actuator 3 acts as a driving force to the left by the force of the clutch spring of a clutch 2. A clutch stroke responding to the engine revolutions is set, and if the present stroke is different from the set stroke, electromagnetic valves V1 and V2 are accelerated or decelerated by the signals from a microcomputer, to increase or reduce the control oil in the actuator 3, to convert the present value at an amount of the set driving amount. Thus, the clutch stroke is driven and controlled securely. Therefore, even if the clutch spring has an unlinear feature, it imposes no influence. Moreover, by setting the driving rate depending on the clutch stepping rate, the control response at the starting can be made smooth.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a method of controlling an automatic clutch of a vehicle, and particularly to a method of controlling the engagement state of a clutch when starting a vehicle.

(Prior Art) Many efforts have been made to automate the clutch in order to reduce the burden on the driver by eliminating the need to operate the clutch pedal and accelerator pedal in conjunction when starting the vehicle. One such method is to use an electronic control device such as a microcomputer to drive and control a clutch drive mechanism to engage and engage the clutch.

For example, in Japanese Patent Application Laid-Open No. 58-225229, an appropriate latch stroke corresponding to the engine speed is determined, and the difference between the position of the clutch actuator piston corresponding to the stroke and the current position of the clutch actuator piston is determined. When this difference is large, the piston
Increase the operating speed.

When this difference is small, the operating speed of the piston is slowed down to control the clutch actuator. According to this, it is possible to automatically realize a so-called half-clutch state in which a lack of engine torque is compensated for by clutch capacity (transmitted torque).

(Problems to be Solved by the Invention) In the above method, since the clutch stroke is controlled by the speed of the clutch actuator, it is necessary to ensure the set speed. Therefore, when the clutch spring exhibits nonlinear characteristics, there is a drawback that the drive mechanism for ensuring the set speed becomes complicated.

An object of the present invention is to appropriately control the clutch engagement state from clutch disengagement to clutch engagement without complicating the drive mechanism.

[Structure of the invention]

(Means for solving the problem) In order to achieve the above object, in the present invention, a clutch stroke is set according to the engine rotation speed; when the current clutch stroke is different from the set clutch stroke; The mechanism is energized, and when the clutch stroke is displaced by a set drive amount, the clutch drive mechanism is deenergized.

(Operation) According to this, since the current value of the clutch stroke is displaced by the set drive amount, the clutch stroke can be reliably driven and controlled, and even when a non-linear spring is used as the clutch spring, it is not affected by this.

Furthermore, by setting the set drive amount according to the amount of depression of the accelerator pedal, the control response at the time of starting becomes smooth.

Other objects and features of the present invention will become clear from the following description with reference to the drawings.6 Embodiments FIG. 1 shows an automatic clutch device embodying the present invention in one embodiment. Referring to FIG. 1, l is the flywheel, 2
is a clutch, 3 is an actuator for driving the clutch, 4 is a feed pipe, 5 is a pump, 6 is a drain, 7 is a return pipe, and 8 is a potentiometer.

The actuator 3 is equipped with a piston 31, a piston rod 31a of the piston 31 is engaged with the release fork 21 of the clutch 2, and a piston rod 31b is engaged with a movable contact of the potentiometer 8.

A force that presses the clutch plate toward the flywheel is constantly applied to the pressure plate of the clutch 2 by a clutch spring. This force acts on the piston 31 of the actuator 3 via the release fork 21 as a leftward driving force.

The solenoid valve v1 for clutch release inserted into the feed pipe 4 closes its hole when deenergized.

Opens the valve hole when energized. The electromagnetic valve v2 for clutch engagement inserted in the return pipe 7 has its hole open when deenergized, and closes when it is energized.

If both electromagnetic valves Vl and V2 are deenergized, the force of the clutch spring acts on the piston 31 of the actuator 3 via the release fork 21, so the control oil flows from the hydraulic chamber 32 of the actuator 3 to the valve v2 to the return pipe 7. Flows with drain 6. That is, the electromagnetic valve Vl
, V2 are both deenergized, the clutch is engaged.

When both electromagnetic valves Vl and V2 are energized (pump 5 is energized), the control oil is pumped from drain 6 to valve v1 to feed pipe 4 to actuator 3.
The hydraulic chamber 32 and the piston 3 of the actuator 3 are
1 to the right, and the release fork 21
It acts against the clutch spring through. That is, when both the electromagnetic valves Vl and V2 are energized, the clutch is disengaged.

Therefore, an arbitrary clutch stroke can be set by controlling the energization/deenergization of the electromagnetic valves v1 and v2.

Potentiometer 8 outputs a voltage corresponding to the position of piston 31, that is, the clutch stroke.

FIG. 2 shows the configuration of an electric control system that controls the engagement state of the clutch device.

The main body of this control system is the microcomputer 13 (
A solenoid driver 15, a waveform shaping circuit 18, a data selector 21, an A/D converter 22a, etc. are connected to its input/output ports.

The solenoid driver 15 includes the aforementioned electromagnetic valve Vl,
V2 and shift gear drive solenoids are connected, and are energized in response to control signals from the main CPU 13.

The waveform shaping circuit shapes the waveforms of the ignition pulse from the pulse generator of the ignition circuit and the vehicle speed pulse from the vehicle speed sensor for the speedometer. These data are input to the main CPU 13 as engine rotation speed data and vehicle speed data.

The contact input circuit 19 detects the on/off states of the select lever position switch, gear position switch, foot brake switch, idle up switch, etc. and transfers it to the data selector 21. The data selector 21 responds by selecting on/off data for these switches in response to instructions from the main CPU 13.

The analog input circuit 20 is a low-pass filter, and is connected to an accelerator pedal sensor, a throttle position sensor, and a clutch stroke sensor. The clutch stroke sensor is the aforementioned potentiometer 8. The accelerator pedal sensor is a potentiometer that outputs a voltage corresponding to the amount of depression of the accelerator pedal.

The configuration of the accelerator pedal is shown in FIG. In this,
Reference numeral 9 denotes an accelerator pedal, which is supported via a link mechanism 10 by a tension coil spring 11 so as to float above the floor. When the driver depresses the pedal 9, the link mechanism rotates to the left and drives the movable contact of the potentiometer 12, so that a voltage output corresponding to the amount of accelerator pedal depression can be obtained. Also the throttle position sensor.

Like these, it is a potentiometer that is engaged with the throttle of the carburetor, and outputs a voltage that corresponds to the throttle opening.

These outputs have vibration components removed in the analog input circuit 20, are digitally converted in the A/D converter 22a, and are input to the main CPU 14.

When the microcomputer 14 (sub CPU) receives data such as the amount of depression of the accelerator pedal 9, throttle opening data, and a throttle level indication signal from the main CPU 13, it provides a signal for opening and closing the throttle to the step motor driver 16. Upon receiving this signal, the step motor driver 16 energizes the step motor unit 17 that opens and closes the throttle valve.

The internal ROM of the main CPU 13 includes a program for controlling the engagement state of the clutch at the time of starting in response to these inputs, a program for controlling the engagement state of the clutch at the time of gear shift, a table for determining control parameters, etc. is included. The outline of the control operation according to the program for controlling the engagement state of the clutch at the time of starting is as follows.

First, when the engine is idling and the vehicle is stopped (the accelerator pedal is not depressed), both electromagnetic valves v1 and v2 are energized to disengage the clutch as described above.

When the accelerator pedal is depressed and the engine speed increases, the engine speed N at that time corresponds to that. Clutch stroke (target stroke) ST,
A set drive amount (step value) ΔS corresponding to the amount of depression of the accelerator pedal (accelerator pedal displacement) is set.

In both cases, the right direction in FIG. 1 is set as positive. The clutch stroke S when stopped is S.

(Clutch disengaged), therefore, set SQ+ΔS as the temporary target stroke Sk, and deenergize the electromagnetic valves v1 and v2 while monitoring the clutch stroke S, so that S=S k
When this happens, valve 2 is energized.

Here, the clutch stroke 5 (=Sk) and the target stroke S are compared, and if it is smaller than 8 teeth, the provisional target stroke Sk is updated by adding the increment value ΔS to the latch stroke S, and the above control is repeated.

The displacement of the clutch stroke for each step value ΔS indicates the displacement speed of the clutch stroke when viewed per unit time. This will be explained with reference to FIG.

For example, the broken line a shown in FIG. 7 shows the case where the displacement of ΔSa is performed at a rate of one predetermined dt waiting time.

In this case, even if the speed of the piston 31 at each displacement is not constant due to the characteristics of the clutch spring, etc., the clutch stroke as a whole is displaced at the speed ΔS a /d t from the stroke So at which the clutch is disengaged. Therefore, if the step value is set to a value Δsb smaller than ΔSa, the clutch stroke will be displaced at the speed ΔSb/dt, as shown by the broken line. That is, when it is desired to increase the speed at which the clutch is engaged, the value of the step value ΔS is increased, and when it is desired to slow down the speed at which the clutch is engaged, the value of the step value ΔS is reduced. In this example.

When the displacement of the accelerator pedal 9 is large, the driver suddenly presses J! The increment value is increased because the driver intends to start the vehicle slowly, and when the displacement of the accelerator pedal 9 is small, the increment value is decreased because the driver intends to start slowly.

Clutch stroke S reaches the target stroke that has already been set.
98, the current value Vs of the vehicle speed is compared with the vehicle speed VN that should be obtained from the engine speed N. When this difference (VN-V8) is within a predetermined range, the clutch is fully engaged, but if it is outside the predetermined range, the target stroke ST is updated from the engine speed at that time, and the above-described control is repeated.

FIG. 8a is a flowchart showing details of the operation of one or more main CPUs 13, and FIG. 8b is a flowchart showing details of the operation of one or more main CPUs 13.

3 is a flowchart showing the energization/deenergization control operation of electromagnetic valves (1) and (2) executed by the main CPU 13 in response to a timer interrupt. Description will be given with reference to these drawings.

When the starting routine is started, in step 1, the initial state is set by setting the target stroke S and the tentative target stroke Sk to a clutch stroke So that disengages the clutch. Thereafter, a timer for one interrupt is activated to permit internal interrupts (step 2).

In step 3, the engine rotation speed N from the input port,
The accelerator pedal displacement and vehicle speed Vs are read and written to the internal RAM.

When the accelerator pedal 9 is depressed, the value of D exceeds O (step 4), so in step 5,
The target straw 98 is updated to a value corresponding to the engine speed N. At this time, the graph shown in FIG. 4 is used. Since this graph is stored in the internal ROM in the form of a table, the corresponding target stroke 98 can be determined from the engine speed N.

In step 6, a step value ΔS corresponding to the accelerator pedal depression amount is set. This will be explained with reference to the graph shown in FIG. The graph on the right side of FIG. 5 shows the relationship between the accelerator pedal displacement and the clutch engagement speed V.

The graph on the left shows the relationship between the step value ΔS and the speed V at which the clutch is engaged. That is, it can be seen that in order to obtain the engagement speed v1 corresponding to the accelerator pedal displacement D1, the step value may be set to ΔS1.

In the internal ROM, the graph of FIG. 5 is stored in the form of a table showing the relationship between the accelerator pedal displacement and the step value ΔS.In step 7, the plate target value Sk is updated to a value larger by the step value ΔS.

Step 8 is a dt waiting time delay step. After this, the target stroke ST and the tentative target stroke Sk are compared, and if the value of Sk is smaller than the value of ST, the processing of the above steps is performed in 3-4-5-6-7-8-9-3. −・
...repeat in a loop.

By the way, timer interrupts occur at time intervals shorter than the dt waiting time. Timer interrupts will be explained with reference to Figure 8b.

When a timer interrupt occurs, registers, addresses, etc. are saved (step 30), and the current clutch stroke value S is read from the input port in step 31.

Since the target stroke S is set to a value corresponding to the engine speed N in step 5 (step 32
), the process proceeds to step 33, and the electromagnetic valve v1 for clutch release is deenergized.

In step 34, the current value S of the clutch stroke and the target stroke ST are compared. At this time, if the current value S of the clutch stroke is less than the target stroke S, in step 35, the current value S of the clutch stroke is
and the tentative target stroke Sk. As a result, when the current value S of the clutch stroke becomes a value less than the provisional target stroke Sk, the electromagnetic valve v2 for clutch engagement is deenergized in step 36, and the hydraulic chamber 3 of the actuator 3
Flow the drive oil from step 2 into drain 6.

When the current value S of the clutch stroke becomes a value equal to or greater than the target stroke of 93 strokes in step 34, or when the present value S of the clutch stroke becomes a value equal to or greater than the temporary target stroke Sk in step 37, the clutch stroke is Energize electromagnetic valve v2 for meat.

Thereafter, in step 43, the registers, addresses, etc. are restored and the process returns to the address (step) at which the interrupt occurred.

When the above processing loop is repeated and the tentative target stroke Sk reaches a value equal to or greater than the target stroke S, this loop is exited from step 9.

In step 10, the vehicle speed (hereinafter referred to as calculated speed) VN that should be obtained by the engine speed N is determined from the engine speed N and the gear ratio. Since the gear position at the time of first start is LOW, this value can be uniquely determined.

In step 11, the calculated speed VN and the actual vehicle speed Vs are compared. When the clutch is engaged to a certain extent, the calculated speed VN
The difference between this and the actual vehicle speed Vs becomes smaller. Therefore, if this difference becomes less than a certain value α.

Step 12 disables timer interrupts, step 13
Fully engage the clutch below.

In this case, the current value S of the clutch stroke is read in step 13, and if this value is smaller than the value SM for fully engaging the clutch, the electromagnetic valve v2 for clutch engagement is deenergized in step 15, and the hydraulic pressure of the actuator 3 is When the driving oil in the chamber 32 is flowed into the train 6 and the current value S of the clutch stroke exceeds the value 8M, step 16 is performed.
energizes electromagnetic valve v2 to stop driving the clutch,
Exit the launch routine.

If the accelerator pedal 9 is released during the start of the vehicle, in step 4, it is determined that the driver no longer intends to start the vehicle, and the clutch is disengaged.

In this case, in step 17, the value of the target stroke S is set as the stroke So for disengaging the clutch, and when the tentative target stroke Sk exceeds the target stroke of 98 strokes, in step 19, the value is set to correspond to the engine rotation speed N at that time. Set the step value ΔS. This will be explained with reference to the graph shown in FIG. The graph on the right side of FIG. 6 shows the relationship between the engine speed N and the speed V' for disengaging the clutch, and the graph on the left side shows the relationship between the step value ΔS and the speed V' for disengaging the clutch. It shows the relationship between

As the engine speed N decreases, the engine torque decreases, so it is necessary to disengage the clutch faster, and the step value ΔS also increases. For example, when the engine speed is N1, a speed v2 is required to disengage the clutch, and for this purpose, it is understood that the increment value should be set to ΔS2.

The internal ROM stores the graph of FIG. 6 in the form of a table showing the relationship between the step value ΔS and the engine speed N.

Once the step value ΔS is determined, in step 20, the value of the temporary target stroke Sk is updated to a value smaller by ΔS.

Step 21 is a delay step of dt time, and after this, the processing of the above steps is repeated 18-1 until the value of the temporary target stroke Sk becomes smaller than the target stroke of 98 strokes.
9-20-21-3-4-17-18-... repeat in a loop.

During this time, timer interrupts occur at time intervals shorter than the dt waiting time, and the timer interrupt routine shown in FIG. 8b is executed.

In this case, since the target stroke ST is set to So in step 17, the process proceeds from step 32 to step 38, where the electromagnetic valve v2 for clutch engagement is energized, and in step 39, the clutch stroke read in step 31 is The current value S and the target stroke ST are compared. Here, when the current value S of the clutch stroke exceeds the target stroke of 8 teeth, it is further compared with the tentative target stroke Sk in step 40, and when it also exceeds this value, the electromagnetic valve v1 for clutch release is energized in step 42. The drive oil is force-fed to the hydraulic chamber 32 of the actuator 3.

When the current value of the clutch stroke is less than or equal to the target stroke S in step 39, or in step 40
The current value of the clutch stroke is the temporary target stroke Sk.
When the value is below, the electromagnetic valve (1) is deenergized in S41.

〔Effect of the invention〕

As described above, according to the present invention, since the clutch stroke is displaced by the set drive amount, the clutch stroke can be reliably driven and controlled, and even when a non-linear clutch spring is used, the clutch can be controlled without complicating the drive mechanism. The engagement state of the can be appropriately controlled.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing the configuration of a clutch device that implements one embodiment of the present invention. FIG. 2 is a block diagram showing a schematic configuration of an electric control system that controls the engagement state of the clutch device shown in FIG. 1. FIG. 3 is a partial sectional view showing the mechanism of the accelerator pedal. FIG. 4 is a graph showing the relationship between the clutch stroke corresponding to the engine speed, FIG. 5 is a graph showing the correlation between the accelerator pedal displacement and the clutch engagement speed and increment value. It is a graph showing the correlation between the engine rotation speed, the speed at which the engagement of the clutch is released, and the increment value. FIG. 7 is a graph showing the relationship between the size of the increment value and the displacement speed of the clutch stroke. Figures 8a and 8b show the main CPU shown in Figure 2.
13 is a flowchart showing the general operation of step 13. 1: Flywheel 2: Clutch 3: Actuator 31: Piston 31 a, 31 b: Piston condo 32: Hydraulic chamber 4: Feed pipe 5: Pump 6: Drain 7: Return pipe 8.12: Potentiometer 9: Accelerator pedal 10: Link mechanism 11: Tension coil spring Patent applicant Aisin Seiki Co., Ltd. 5th 6th ■

Claims (3)

[Claims] (1) Set the clutch stroke according to the engine speed; When the current clutch stroke differs from the set clutch stroke; When the clutch drive mechanism is energized and the clutch stroke is displaced by the set drive amount, the clutch is driven. Deenergizing the mechanism; how to control an automatic clutch. (2) The automatic clutch control method according to claim 1, wherein the set drive amount is set in accordance with the amount of depression of the accelerator pedal. (3) The automatic clutch according to claim 1, wherein the clutch drive mechanism is energized and the clutch drive mechanism is deenergized when the clutch stroke reaches a clutch stroke set according to the engine rotation speed. control method.