JP2016023668A - Clutch control method and automatic clutch control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an automatic clutch control device which is favorable in a control response more than before.SOLUTION: When it is determined that a piston stroke amount reaches an indication value, the drive of a clutch actuator is stopped, PID control is performed, an integral term in the PID control is initialized (S106, S108), after that, when it is determined that the piston stroke amount exceeds a prescribed threshold (S110), or when it is determined that a prescribed time elapses after a stop of the PID control (S112), the PID control is resumed (S114), and after an overshoot or an undershoot of the stroke amount, quick convergence to the indication value is performed.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a clutch control method in an automatic clutch control device configured to be able to automatically perform engagement / disengagement of a mechanical clutch, and more particularly to an improvement in control responsiveness, control accuracy, and the like.

As this type of conventional device, for example, various automatic clutch control devices configured to control the engagement / disengagement of the clutch based on the accelerator opening, the engine speed, the shift position of the change lever, etc. have been proposed and put into practical use. (For example, see Patent Document 1).
Such an automatic clutch control device can disengage the clutch by supplying air from the air source to the clutch actuator that engages and disengages the clutch, and actuates the clutch actuator against the urging means such as the clutch spring and the clutch diaphragm. Therefore, the operation control of the solenoid valve that supplies air to the clutch actuator is controlled by the electronic control unit based on the accelerator opening, the engine speed, the clutch stroke, and the like.

JP-A-9-287625 (page 5-13, FIGS. 1-8)

By the way, the drive of the air cylinder that constitutes the clutch actuator has the characteristic that the cylinder does not operate unless the air density exceeds a certain level with respect to the load, and the generation of the drive command and the actual operation of the cylinder start. There is an essentially unavoidable time delay between them.
As a means for biasing the clutch in one direction, a spring, a diaphragm, or the like is used. For example, in the case of a spring, due to its characteristics, even if it is a slight operation, a driving force is required first.

  On the other hand, in the operation control of the clutch actuator by the automatic clutch control device, the PID control is usually used. However, the control delay due to the air density as described above, the action of the spring, etc. In addition to influencing the D term and causing undershoot and overshoot, the increase and decrease of the I term are repeated due to the undershoot and overshoot, so that it takes more time than necessary to converge the control state. This is one factor that hinders the improvement of control responsiveness.

  The present invention has been made in view of the above circumstances, and suppresses a decrease in control response in clutch control due to the air density of the air cylinder and the characteristics of the spring used as the urging means of the clutch. A clutch control method and an automatic clutch control device with better control responsiveness are provided.

In order to achieve the above object of the present invention, a clutch control method according to the present invention includes:
An automatic clutch control device configured so that the engagement / disengagement of the clutch can be automatically controlled based on the PID control so that the piston stroke amount actually detected by the clutch actuator becomes an instruction value calculated based on the operation state of the vehicle. A clutch control method in
When the piston stroke amount reaches the indicated value, the clutch actuator is stopped and the PID control is stopped, and the integral term in the PID control is initialized. After that, the piston stroke amount reaches a predetermined threshold. When the value exceeds or when a predetermined time has elapsed since the PID control is stopped, the PID control is resumed.
In order to achieve the above object of the present invention, an automatic clutch control device according to the present invention comprises:
An electronic control unit configured to control the connection / disconnection of the clutch based on PID control so that the actually detected piston stroke amount of the clutch actuator becomes an instruction value calculated based on the operation state of the vehicle; In the automatic clutch control device
The electronic control unit is
When it is determined that the piston stroke amount has reached the instruction value, the driving of the clutch actuator is stopped and PID control is stopped, and the integral term in PID control is initialized, and then the piston stroke amount is predetermined. When it is determined that the threshold value is exceeded, or when it is determined that a predetermined time has elapsed since the stop of the PID control, the PID control is resumed.

  According to the present invention, it is possible to quickly and surely converge to the indicated value without incurring fluctuations centered on the indicated value of the stroke amount after overshoot, and the control responsiveness is better than before, The effect is that an automatic clutch control device having high stability and reliability can be provided.

It is a block diagram which shows one structural example of a clutch operation apparatus provided with the automatic clutch control apparatus in embodiment of this invention. It is a block diagram which shows the more specific structural example of the automatic clutch control apparatus used for the clutch actuator shown in FIG. It is a subroutine flowchart which shows the procedure of the clutch control process performed by the automatic clutch control apparatus shown by FIG. FIG. 4A is a schematic diagram schematically showing a change in an operation amount and a stroke amount of an air supply valve or an exhaust valve by a clutch control process in the embodiment of the present invention, and FIG. 4A is an air supply valve or an exhaust valve. FIG. 4B is a schematic diagram schematically showing a change in stroke amount. FIG. 5A is a schematic diagram schematically showing a change in an operation amount of an air supply valve or an exhaust valve and a change in a stroke amount by a conventional clutch control process, and FIG. FIG. 5B is a schematic diagram schematically showing a change in stroke amount.

Embodiments of the present invention will be described below with reference to FIGS. 1 to 5.
The members and arrangements described below do not limit the present invention and can be variously modified within the scope of the gist of the present invention.
First, the configuration of a clutch operating device to which an automatic clutch control device according to an embodiment of the present invention is applied will be described with reference to FIG.
A clutch operating device 1 according to an embodiment of the present invention includes a clutch actuator 2 for connecting / disconnecting a clutch, an air pressure source 3 for generating air pressure (compressed air pressure) required for operating the clutch actuator 2, and a clutch actuator 2. The automatic clutch control device 4 that performs the operation control is provided.

  The clutch operated by the clutch operating device 1 is connected by a biasing force of a clutch spring or a diaphragm (not shown) such as the clutch described in Patent Document 1 and a conventionally known clutch. On the other hand, it is configured to be cut by air pressure.

The automatic clutch control device 4 has an intake valve 5, an exhaust valve 6, a transmission electronic control unit 7 for controlling an automatic transmission of the vehicle, and a stroke sensor 8 for detecting a clutch stroke position of the clutch actuator. It is configured.
The transmission electronic control unit 7 includes, for example, a microcomputer (not shown) having a known and well-known configuration, a storage element (not shown) such as a RAM and a ROM, and an input / output. An interface circuit (not shown) is configured as a main component, and shift control processing is executed, and on the basis of conventional clutch control processing, clutch control processing in an embodiment of the present invention described later is performed. It is supposed to be executed. In FIG. 1, the “clutch control unit 13” is realized in particular by executing a clutch control process by a microcomputer (not shown), and conceptually shows such a control part. It is.

  In addition, the supply valve 5 includes a large opening electromagnetic valve 9 for supply and a small opening electromagnetic valve 10 for supply. Similarly, the exhaust valve 6 includes a large opening electromagnetic valve 11 for exhaust. And it has the small opening solenoid valve 12 for exhaust_gas | exhaustion (refer FIG.1 and FIG.2).

The large opening electromagnetic valve 9 for supplying air is an electromagnetic valve that is set so that the valve opening degree is a predetermined large opening degree when the valve is opened.
On the other hand, when the air supply small opening electromagnetic valve 10 is opened, the valve opening is set to a predetermined opening smaller than the valve opening of the air supply large opening electromagnetic valve 9. This is a solenoid valve.
Both the large opening solenoid valve 9 for supply air and the small opening solenoid valve 10 for supply air are normally closed (closed when not operating) solenoid valves.

The above-described valve opening settings of the large opening solenoid valve 9 for air supply and the small solenoid valve 10 for supply air can be similarly applied to the large opening solenoid valve 11 for exhaust and the small opening solenoid valve 12 for exhaust. Therefore, the detailed description here will be omitted.
The exhaust large opening solenoid valve 11 and the exhaust small opening solenoid valve 12 are both normally open (open during non-operation) solenoid valves.
Note that the exhaust large opening solenoid valve 11 and the exhaust small opening solenoid valve 12 can both be configured as normally closed solenoid valves.
In the following description, the exhaust large opening solenoid valve 11 and the exhaust small opening solenoid valve 12 are both described as normally open solenoid valves.

  The air supply sides of the large air opening solenoid valve 9 and the small air opening solenoid valve 10 are connected to the air source 3 through the air passages 14, 15, and 16, respectively. (See FIGS. 1 and 2). Further, the exhaust side solenoid valve 9 for supply and the small opening solenoid valve 10 for supply are respectively connected to the exhaust large opening solenoid valve 11 and the exhaust small opening solenoid via the air passages 17 and 18, respectively. It is connected to each supply side of the valve 12 (see FIG. 2).

The air passages 17 and 18 are connected to each other through an air passage 19 and are connected to the clutch actuator 2 through an air passage 20.
Therefore, the exhaust side of the large opening solenoid valve 9 for supply and the small opening solenoid valve 10 for supply, and the supply side of the large opening solenoid valve 11 for exhaust and the small opening solenoid valve 12 for exhaust, It is connected to the actuator 2.
Further, each exhaust side of the exhaust large opening solenoid valve 11 and the exhaust small opening solenoid valve 12 is connected to the outside through the air passages 21, 22, and 23.

The large air opening solenoid valve 9 and the small air opening solenoid valve 10 for supply, and the large opening electromagnetic valve 11 for exhaust and the small opening solenoid valve 12 for exhaust are all electronic control units 7 for transmission. The conventional clutch control unit 13 is driven and controlled by, for example, PWM (Pulse Width Modulation) control, as in the prior art.
For example, in the state where the key switch (not shown) of the vehicle is turned off, as shown in FIG. 2, both the large opening electromagnetic valve 9 for supply air and the small opening electromagnetic valve 10 for supply are both On the other hand, the exhaust large opening solenoid valve 11 and the exhaust small opening solenoid valve 12 are both opened.
Therefore, in this state, air is discharged from the clutch actuator 2, and the clutch actuator 2 becomes inactive and is connected by a clutch spring (not shown) (normal clutch connection state).

Next, in this state, for example, when a key switch (not shown) is turned on while a brake pedal (not shown) is depressed in order to start the engine of the vehicle, an electronic control unit for transmission 7, the exhaust valve 6 is closed and the air supply valve 5 is opened.
As a result, air is supplied to the clutch actuator 2 through the intake valve 5, and when the piston pressing force by the air pressure overcomes the urging force of the clutch spring (not shown) against the piston 2a, the piston 2a strokes and the clutch actuator 2 will start operation.
When the piston 2a is stroked for the first predetermined amount, the clutch (not shown) is lightly connected to be in a half-clutch state, and when the piston 2a is further stroked for the second predetermined amount, the clutch (not shown) is disconnected. It becomes.

In this case, when only the small opening solenoid valve 10 for air supply is opened, a relatively small flow rate of air is supplied to the clutch actuator 2, so that the stroke speed of the piston 2a of the clutch actuator 2 becomes relatively slow. On the other hand, when only the air supply large opening solenoid valve 9 is opened, a relatively large flow of air is supplied to the clutch actuator 2, so that the stroke speed of the piston 2a is the air supply small opening solenoid valve 10. It is faster than when only the valve is opened.
Further, when both the large opening solenoid valve 9 for air supply and the small solenoid valve 10 for air supply are opened, a further large flow of air is supplied to the clutch actuator 2, so that the stroke speed of the piston 2a is increased. Is faster than the case where only the large air opening solenoid valve 9 is opened.

On the other hand, when the clutch 2 is stroked to the clutch disengagement position, that is, from the disengaged state of the clutch, the clutch actuator is stroked in the non-operation direction (left direction in FIG. 2) to connect the clutch. Thus, the air supply valve 5 is closed by the clutch control unit 13, while the exhaust valve 6 is opened.
As a result, air is discharged from the clutch actuator 2 through the exhaust valve 6 and discharged to the outside. The piston 2a starts a stroke in the non-operation direction, and after a predetermined amount of stroke, the clutch (not shown) is lightly connected. Half-clutch state.
When the piston 2a further strokes in the non-operation direction, the clutch is in a normal state in which it is strongly connected.

In this case, when only the exhaust small opening solenoid valve 12 is opened, a relatively small flow rate of air is discharged from the clutch actuator 2, so that the stroke speed of the piston 2a of the clutch actuator 2 becomes relatively slow. When only the exhaust large opening solenoid valve 11 is opened, since a relatively large flow of air is discharged from the clutch actuator 2, the stroke speed of the piston 2a is such that only the exhaust small opening solenoid valve 12 is opened. It will be faster than if it was spoken.
Furthermore, when both the exhaust large opening solenoid valve 11 and the exhaust small opening solenoid valve 12 are opened, a further large flow of air is discharged from the clutch actuator 2, so that the stroke speed of the piston 2a is: This is even faster than when only the exhaust large opening solenoid valve 11 is opened.

  As described above, in the clutch operating device 1 according to the embodiment of the present invention, the large opening solenoid valve 9 for supply air and the small opening solenoid valve 10 for supply air, and the large opening solenoid valve 11 for exhaust and the small opening solenoid valve for exhaust are used. The solenoid valves 12 can be driven individually, and the operation speed of the clutch actuator 2, that is, the stroke speed of the piston 2 a can be adjusted to a desired magnitude by appropriately using the solenoid valve 12. The clutch stroke of the clutch actuator 2 can be made to reach the target clutch stroke value with high accuracy in a short time.

Furthermore, in the embodiment of the present invention, the characteristics of the spring used as the air density of the air cylinder and the urging means of the clutch in the conventional apparatus as described in the background art by the clutch control process as described below. It is possible to suppress a decrease in control response in the clutch control caused by the above and improve the control response.
FIG. 3 is a subroutine flowchart showing the procedure of the clutch control process in the embodiment of the present invention executed by the clutch control unit 13. Hereinafter, the clutch in the embodiment of the present invention will be described with reference to FIG. The control process will be described.

First, the automatic clutch control device 4 according to the embodiment of the present invention is based on PID control so that the actual piston stroke amount detected by the stroke sensor 8 becomes an instruction value calculated based on the operation state of the vehicle. The clutch control processing in the embodiment of the present invention described below is further performed on the premise that the clutch is connected and disconnected so as to perform so-called conventional clutch control processing. It has become.
Hereinafter, specifically, when processing by the clutch control unit 13 is started, it is determined whether or not an operation command for the clutch actuator 2 is generated (see S102 in FIG. 3).
That is, in a main routine (not shown), a main clutch control process that is executed in the same manner as in the prior art is executed, and it is determined whether or not the latch actuator 2 needs to be driven based on the driving situation of the vehicle. Yes.
Therefore, in step 102, it is sufficient to use the determination result of whether or not the above-described clutch actuator 2 needs to be driven in the main routine.

  If it is determined in step S102 that it is determined that the driving of the clutch actuator 2 is necessary (in the case of YES), the process proceeds to step S104 described below, while the driving of the clutch actuator 2 is necessary. If it is determined that it is determined that it is not (NO), the process is terminated as it is not necessary to perform a series of processes thereafter, and the process returns to the main routine (not shown).

Next, in step S104, a valve drive signal is output to the supply valve 5 or the exhaust valve 6 in accordance with the drive direction of the piston 2a of the clutch actuator 2 determined in a main routine (not shown).
Here, the valve drive signal is a PWM signal in PWM control as described above, and for convenience of explanation, the PWM signal output to the supply valve 5 is referred to as a “supply duty signal”, and The PWM signal output to the exhaust valve 6 will be referred to as a “supply duty signal” (see FIG. 1).

Next, the actual stroke amount of the piston 2a detected by the stroke sensor 8 (hereinafter referred to as “actual stroke amount” for convenience of explanation) is calculated and calculated based on the operating state of the vehicle in a main routine (not shown). Is determined (see step S106 in FIG. 3), and if it is determined that it has been exceeded (in the case of YES), the process proceeds to step S108 described below.
Here, the instruction value is a stroke amount of the piston 2a desired based on the operation state of the vehicle, in other words, a target value.

Next, in step S108, in response to the actual stroke amount exceeding the instruction value, the output of the valve drive signal is stopped, the PID control is stopped, and the I term (integral value) in the PID control is stopped. Initialization is executed. Here, initialization means that the value of the I term is zero.
Next, it is determined whether or not the actual stroke amount of the piston 2a detected by the stroke sensor 8 has exceeded a threshold value (see step S110 in FIG. 3). If it is determined that the threshold value has been exceeded (YES) In this case, the clutch control by the PID control is started again (see step S114 in FIG. 3).

  On the other hand, if it is determined in step S110 that the actual stroke amount has not yet exceeded the threshold value (in the case of NO), the valve drive signal output is stopped in the previous step S108 and at the same time the PID control is performed. It is determined whether or not a predetermined time has elapsed since the stop (see step S112 in FIG. 3). If it is determined that the predetermined time has elapsed (in the case of YES), the process proceeds to step S114. If it is determined that the predetermined time has not yet elapsed (in the case of NO), the process returns to the previous step S110 and the determination result in step S110 is YES, or the determination result in step S112 is YES. These processes are repeated until

Next, the significance of executing the clutch control process as described above will be described with reference to the schematic diagrams of FIGS.
First, FIG. 5A shows the operation amount of the air supply valve 5 or the exhaust valve 6 in the conventional clutch control, and FIG. 5B shows the operation amount of the air supply valve or the exhaust valve shown in FIG. It is the schematic diagram which showed typically the change of the stroke amount with respect to the operation amount, respectively.

  Here, “the operation amount of the air supply valve or exhaust valve” means the amount of the valve drive signal applied to the air supply valve or the exhaust valve in order to operate the clutch actuator 2 and move the piston 2a to a desired position. More specifically, in the embodiment of the present invention, it is the magnitude of the duty of the air supply duty signal and the exhaust duty signal. In general, as the duty of the duty signal increases, the amount of current supplied to the air supply valve or the exhaust valve increases, and the opening degree of the air supply valve or the exhaust valve increases.

In FIG. 5A, if the positive region of the operation amount is the operation amount of the air supply valve 5, for example, the negative region corresponds to the operation amount of the exhaust valve 6.
For example, if the exhaust valve 5 is driven with a required operation amount in order to obtain a stroke amount of a certain indicated value (see FIG. 5B), the piston 2a starts to move, and the stroke amount increases with time. It increases toward the indicated value (see FIG. 5B).
As described in the background art, even if the stroke amount reaches the indicated value due to the characteristics of the air used for the operation of the clutch actuator 2 or the characteristics of the spring as a means for biasing the clutch in one direction. It does not stop immediately (refer to FIG. 5B), and overshoot generally occurs.

An operation amount based on PID control is given to the exhaust valve 6 instead of the air supply valve 5 in order to return the piston 2a to the original position at the same time as the stroke amount exceeds the indicated value (FIGS. 5A and 5). (See the location at time t1 in (B)), and then the amount of stoke becomes a peak and then reverses toward the indicated value (see FIG. 5B).
Thereafter, the stroke amount gradually converges to the instruction value while moving up and down a plurality of times around the instruction value (see FIG. 5B).

  As described above, in the conventional clutch control, the change in the stroke amount after the overshoot or the undershoot occurs in the PID control is added / subtracted to the I term (integral term) sequentially. After overshooting, it is difficult to avoid the so-called stroke amount vibration phenomenon that repeats vertical movement around the indicated value.

  On the other hand, FIG. 4A shows the operation amount of the supply valve 5 or the exhaust valve 6 when the clutch control process in the embodiment of the present invention is executed, and FIG. 4B shows the operation amount of FIG. FIGS. 4A and 4B are schematic diagrams schematically showing changes in the stroke amount with respect to the operation amount of the intake valve 5 or the exhaust valve 6 shown in FIG. Corresponds to FIG. 5B, respectively.

As in the description of FIG. 5, for example, when the exhaust valve 5 is driven at a certain operation amount, the conventional clutch control is performed until the stroke amount increases toward the instruction value and overshoots exceeding the instruction value. (See FIGS. 4A and 4B and FIGS. 5A and 5B).
In the embodiment of the present invention, when the stroke amount exceeds the instruction value, the output of the valve drive signal is stopped, the PID control is stopped, and the I term is initialized (step S106 in FIG. 3). , S108). Such processing is executed at time t1 in FIG.

Even if the output of the valve drive signal is stopped and the PID control is stopped, the stroke amount exceeds the indicated value due to delay in circuit operation, inertia of the piston 2a, etc., and overshoot occurs. Then, after the stroke amount exceeds the indicated value, it exceeds a predetermined threshold value (denoted as “th” in FIG. 4B) (at time t2 in FIG. 4B), or PID control When a predetermined time has elapsed since the stop, the PID control is resumed (see steps S110, S114, and S112 in FIG. 3).
Here, when the stroke amount overshoots as shown in FIG. 4, the threshold value th is set to a range that is a predetermined value α higher than the indicated value and that does not exceed the peak value of the overshoot. Is. It is preferable to select an appropriate value for the predetermined value α based on test results and simulation results in consideration of specific specifications of the vehicle.

  FIG. 4 shows an example in which the stroke amount overshoots, but the clutch control processing in the embodiment of the present invention is not only applied to the case where the stroke amount overshoots, but, of course, applies similarly to the case of undershooting. In this case, the threshold value th is set to a value that is lower by a predetermined value β than the indicated value in which the undershoot has occurred. In this case, the predetermined value β is a specific value of the vehicle. Appropriate specifications should be taken into consideration based on test results and simulation results.

Also, for the predetermined time, it is preferable to select an appropriate one based on test results and simulation results in consideration of specific specifications of the vehicle.
The condition for restarting PID control is that the threshold value is exceeded or that the predetermined time has elapsed, because overshoot (or undershoot) does not necessarily exceed the threshold value, This is because when a relatively long time is required even if the threshold value is exceeded, it is considered that resuming PID control is a good measure in consideration of the stability and responsiveness of clutch control.

Thus, the stroke amount exceeds the threshold value, or the PID control is resumed after a predetermined time has elapsed from the stop of the PID control, and the stroke amount is controlled to become the indicated value. In FIG. 3, since the I term is initialized before the PID control is resumed (see step S108 in FIG. 3), the stroke amount after the PID control resumes is directed toward the instruction value unlike the conventional case. After reaching the value, the indication value or the value near the pole converges with almost no vibration (see FIG. 4B).
Note that the operation amount in FIG. 4A is described as the operation amount for the entire supply valve 5 or the exhaust valve 6, and the supply valve 5 and the exhaust valve 6 are as shown in the embodiment of the present invention. When each is configured using a solenoid valve with a large and small opening and can be driven separately, it is arbitrary whether to use these separately or not, and it is not necessary to be limited to a specific driving mode. Is.

  It is suitable for a vehicle in which further improvement in control response and stability is desired without being affected by the air density of an air cylinder constituting the clutch actuator and the characteristics of a spring used as a biasing means of the clutch.

DESCRIPTION OF SYMBOLS 1 ... Clutch actuator 2 ... Clutch actuator 3 ... Air source 4 ... Automatic clutch control device 5 ... Supply valve 6 ... Exhaust valve 7 ... Electronic control unit 13 for transmissions ... Clutch control part

Claims (2)

An automatic clutch control device configured so that the engagement / disengagement of the clutch can be automatically controlled based on the PID control so that the piston stroke amount actually detected by the clutch actuator becomes an instruction value calculated based on the operation state of the vehicle. A clutch control method in
When the piston stroke amount reaches the indicated value, the clutch actuator is stopped and the PID control is stopped, and the integral term in the PID control is initialized. After that, the piston stroke amount reaches a predetermined threshold. A clutch control method characterized by restarting PID control when a value is exceeded or when a predetermined time has elapsed since the PID control was stopped. An electronic control unit configured to control the connection / disconnection of the clutch based on PID control so that the actually detected piston stroke amount of the clutch actuator becomes an instruction value calculated based on the operation state of the vehicle; In the automatic clutch control device
The electronic control unit is
When it is determined that the piston stroke amount has reached the instruction value, the driving of the clutch actuator is stopped and PID control is stopped, and the integral term in PID control is initialized, and then the piston stroke amount is predetermined. An automatic clutch configured to resume PID control when it is determined that the threshold value of the PID control has been exceeded, or when it is determined that a predetermined time has elapsed since the stop of the PID control. Control device.

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