JP3511958B2 - Hybrid vehicle clutch control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To acurately control a clutch, located at the drive system of a vehicle, with excellent responsiveness. SOLUTION: In a parallel type hybrid vehicle wherein a first clutch 7 is located between an engine 1 and a motor 2 and a second clutch 8 is located between the motor 2 and drive wheels 4W, a control means 30 maintains a nonobjective clutch, of first and second clutches 7 and 8 in a release state by the command of a first command means 32 and rotationally drives the motor 2 by the command of a second command means 33 and engages an objective clutch. When rotation fluctuation is detected during engaging operation of the objective clutch, a current engaging command value forms a learning value and is stored at a memory 44. Control during non-engagement of the objective clutch is carried out based on a reference command value reduced and corrected to the non-engaging side by decreasing the stored leaning value to the non- engagement side by a given amount.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a clutch control device for a hybrid vehicle, which can drive the vehicle by one or both of an engine and a motor.

[0002]

2. Description of the Related Art In recent years, an electric motor (hereinafter simply referred to as a motor) is used as a drive source for a vehicle, and an internal combustion engine (engine) is used as a drive source for the vehicle or a drive source for a generator. Hybrid vehicles) are being developed. One of them is a parallel hybrid vehicle that can use both a motor and an engine as drive sources for the vehicle.

[0003]

By the way, as an example of the structure of a parallel type hybrid vehicle, as shown in FIG. 4, an engine 1, a motor 2, and an input shaft 3A of a transmission 3 are arranged on the same axis. , The output shaft 3B of the transmission 3 to the power transmission gear 5
Drive shaft 4L via a differential (differential) 6 or the like,
Some are connected to 4R. A first clutch (input clutch) 7 is provided between the engine 1 and the motor 2, and when the engine 1 is stopped and only the motor 2 travels, the input clutch 7 is disengaged. The input clutch 7 is connected when it is operated and used as a drive source. In addition, a second clutch (output clutch) 8 is provided between the motor 2 and the drive wheels, and the vehicle is stopped while operating the engine 1 for power generation (battery charging), driving auxiliary equipment, or the like. Alternatively, when traveling at a slow speed, the output clutch 8 is disengaged or slip-engaged to control the engagement state between the engine and the drive system of the vehicle.

As a mechanism for controlling the engagement state of the input clutch 7 and the output clutch 8, for example, a hydraulic control type mechanism as shown in FIG. 5 can be considered. That is, as shown in FIG. 5, the main bodies of the clutches 7 and 8 are the first rotating member (shaft member).
11 and a second rotating member (case) 12, one of the first rotating member 11 and the second rotating member 12 has an input shaft to the clutches 7 and 8 (for example, an output shaft 1A of the engine 1 and a transmission 3). Output shaft 3B) is coupled to the other, and the output shafts to the clutches 7 and 8 (for example, the input shaft 2A of the motor 2 and the input shaft 3A to the transmission 3) are coupled to the other.

Further, the main body of the clutch 7, 8 has a first
A plurality of clutch discs 1 that rotate integrally with the rotating member 11.
1A and a plurality of clutch discs 12A that rotate integrally with the second rotating member 12 are alternately arranged with a viscous fluid in between, and a piston 13 that engages the clutch discs 11A and 12A with each other is provided. Piston 13
Is urged by a return spring 14 so as to retreat to a side where the clutch disks 11A and 12A are disengaged, and a hydraulic chamber 15 formed between the piston 13 and the second rotating member (case) 12 In response to the hydraulic pressure, the piston 13 moves forward against the return spring 14,
Both clutch disks 11A and 12A are engaged.

A hydraulic control mechanism 20 for adjusting the hydraulic pressure (control hydraulic pressure) in the hydraulic chamber 15 includes an oil pump 21 for pressurizing hydraulic oil, a pressure regulating valve 22, and a space between the oil pump 21 and the pressure regulating valve 22. The oil passage 23 is interposed and the oil passage 24 is interposed between the pressure regulating valve 22 and the hydraulic chamber 15. The oil pressure from the oil pump 21 is adjusted by the pressure regulating valve 22 and output. The hydraulic pressure inside and inside the hydraulic chamber 15 is adjusted.

The pressure regulating valve 22 adjusts the opening of each of an input port 22A to which the discharge pressure (original pressure) from the oil pump 21 is constantly supplied and an EX port 22B for letting out pressure oil to the outside, and adjusts the output port 22C to the same. It is output and the pressure in the oil passage 24 and the hydraulic chamber 15 is adjusted. Input port 22A and EX port 2
2B is opened by the linear solenoid 22E.
It is adjusted by driving 2D in the axial direction. Further, the pressure regulating valve 22 linearly adjusts the supply pressure to the hydraulic chamber 15 from the maximum hydraulic pressure state close to the original pressure to the minimum hydraulic pressure state of 0 (= atmospheric pressure) by the linear solenoid 22E controlled by the controller 30. be able to.

As a result, when one of the clutches, for example, the clutch 7, is operated, the output pressure obtained by appropriately adjusting the original pressure by the pressure adjusting valve 22 is output to the output port 22C to properly adjust the hydraulic pressure in the hydraulic chamber 15. Adjust to a proper pressure. As a result, the piston 13 moves forward and the clutch disc 11A,
12A is pressed against each other to be engaged with each other and torque is transmitted. At this time, if the output pressure is finely adjusted by the pressure regulating valve 22, the clutch 7 can be slip-engaged and the amount of transmission torque can be adjusted. If the output pressure is increased above this slip region, the clutch 7 will be opened. The transmission torque amount can be maximized by engaging in the direct connection state.

When the clutch 7 is deactivated, the pressure regulating valve 22 minimizes the output pressure (= 0) to minimize the hydraulic pressure in the hydraulic chamber 15 (that is, 0 = atmospheric pressure). As a result, the return spring 14 cannot be fully resisted, and the piston 13 is retracted and the clutch disks 11A, 1
The pressing force does not work on 2A and they are separated from each other and the torque cannot be transmitted. Further, when the hydraulic pressure in the hydraulic chamber 15 is minimized (= 0), the piston 13 is most retracted by the urging force of the return spring 14.
Between the working end (clutch disc pressing end) 13A and the clutch discs 11A and 12A (end play)
As a result, drag torque resistance can be completely prevented.

However, if the mechanism for controlling the engagement state of the clutch 7 is controlled in this way, the following problems occur. With the clutch disengaged, the oil passage 24
And the hydraulic pressure (control hydraulic pressure) in the hydraulic chamber 15 is 0 (= atmospheric pressure)
Since the operating oil has been drained, the oil passage 2 will be released when the clutch engagement command is issued from this state.
4 and the hydraulic chamber 15 before actuation of the piston 13 are filled with hydraulic oil, and after the filling is completed, the hydraulic pressure of the hydraulic oil is increased to the control hydraulic pressure to operate the piston 13. Therefore, a response delay occurs after the clutch engagement command is issued until the clutch is actually engaged. In particular,
The time until the hydraulic passage 15 is filled with the hydraulic oil before the piston 13 actually operates and the hydraulic chamber 15 before the piston 13 is activated is filled with the hydraulic oil is a major factor of the response delay. There is. This is a disadvantage when trying to quickly engage the clutch.

There are various ways of releasing the hydraulic oil in the oil passage 24 and the hydraulic chamber 15. That is, when the temperature of the hydraulic oil is high, the viscosity of the hydraulic oil is lowered, and the hydraulic oil easily comes off. Along with this, unless hydraulic pressure is applied to the hydraulic chamber 15 and the oil passage 24, air gradually enters the inside through the gaps between these parts. The amount of air that enters the hydraulic circuit that is not subjected to this hydraulic pressure is affected by the temperature of the hydraulic oil, the time after the hydraulic pressure is reduced, the working accuracy of the hydraulic circuit, and other factors, and therefore varies. Have difficulty. The variation in the residual hydraulic oil amount in the hydraulic circuit hinders accurate clutch control, and is disadvantageous when it is desired to quickly engage the clutch.

The present invention was devised in view of the above-mentioned problems, and clutch control of a hybrid vehicle is made so that the clutch interposed in the drive system of the hybrid vehicle can be controlled accurately and responsively. The purpose is to provide a device.

[0013]

Therefore, in the clutch control device for a hybrid vehicle according to the first aspect of the present invention, the engine, the motor and the drive wheels are provided in this order in the drive system of the vehicle, and the engine and the In a parallel hybrid vehicle capable of driving a vehicle by a motor, a first clutch is interposed between the engine and the motor, and a second clutch is interposed between the motor and the drive wheel. The disengagement of one clutch enables the vehicle to be driven only by the motor, and the disengagement of the second clutch allows the drive system of the vehicle to be disconnected from the engine and the motor. In order to control the disengagement of the first clutch or the second clutch (non-engagement control or disengagement control), the control means receives the first clutch and the second clutch in response to a command from the first command means. One of the clutches is maintained in a disengaged state, and in this state, the motor is rotationally driven by the command of the second command means, and the other clutch of the first clutch and the second clutch is operated. When the other clutch is engaged and the rotational fluctuation of the other clutch is detected during the engaging operation of the other clutch, the engagement command value at this time is stored as a learning value in the storage unit.

As described above, since the motor is used as the clutch drive source, the engagement command value can be learned in a stable state and in an extremely low speed rotation state, and the learning accuracy can be improved. Due to the improvement, the torque transmission starting point of the clutch can always be accurately determined regardless of the change with time of the clutch. In particular, the first clutch is slip-controlled when starting an engine that was in a stopped state while the motor is running or running at a very low speed while the motor is running, but since the torque transmission starting point of the clutch is set accurately. It is possible to perform optimum slip control.

According to another aspect of the present invention, there is provided a clutch control device for a hybrid vehicle according to a second aspect of the present invention, wherein the reduction correction means reduces the learning value stored in the storage means to a release side by a predetermined amount and applies the reduction correction value. Calculated as the reference command value for combined control,
The operation control means controls the operation of the other clutch based on the reduction correction value [that is, the reduction-corrected command value (PCL-α)]. During the operation control by the operation control means, the predetermined amount increase correction means increases the predetermined amount until the rotational fluctuation of the other clutch is detected. Then, when the rotation fluctuation is detected during the operation control by the operation control means, the second storage means stores the predetermined amount when the rotation fluctuation is detected as the learning value. Further, the decrease correction means uses the second learning value as the predetermined amount if the second learning value is stored in the second storage means, and stores the second learning value in the second storage means. If the learning value of is not stored, a preset value is used as the predetermined amount.

Thus, when an engagement command is issued when the first clutch or the second clutch is disengaged, the reduction correction value is controlled as a command value so that the clutch does not drag and is in a state of being on the verge of engagement. When the clutch engagement command is issued, the clutch can be engaged more responsively. Further, the learning value is obtained by the stable rotation while the differential rotation is given to the clutch by rotationally driving the motor, and the learning value is obtained by slightly changing the decrease correction value to obtain the learning value. Based on this, it is possible to accurately obtain the decrease correction value based on the above, and it is possible to more accurately hold the clutch in the state of just before engagement when the clutch is disengaged.

According to another aspect of the present invention, there is provided a hybrid vehicle clutch control device according to the present invention, wherein the evaluating means provided in the control means uses the operation control means as the reference command value during engagement control. The other clutch is controlled, and the response time from the engagement command time to the engagement of the other clutch is obtained, and whether the decrease correction value is appropriate as the reference command value at the time of engagement control based on the response time. Evaluate whether or not.

Therefore, when the reduction correction value is not appropriate as the reference command value at the time of engagement control, the reduction correction value is reset until it becomes appropriate, so that the clutch can be surely held in the state just before the engagement. It is possible to set the reduction correction value that can be set, and by using the reduction correction value as the reference command value during the engagement control, it is possible to more reliably improve the engagement responsiveness of the clutch. The high of the present invention according to claim 4.
In a clutch control device for a brid car, the control means is
Operate the motor with a constant torque to
While rotating the clutch element on the motor side at a very small speed,
Gradually increase the engagement command value of the learning target clutch,
The moment when the clutch to be learned is engaged is determined.
The learning value is stored based on the engagement command value of.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to the drawings. FIGS. 1 to 3 show a clutch control device for a hybrid vehicle as one embodiment of the present invention. FIG. A block diagram showing its configuration, and FIGS. 2 and 3 are flow charts showing its control contents.
Note that FIGS. 4 and 5 already described are also used in the description of the present embodiment.

In the hybrid vehicle according to the present embodiment, as shown in FIGS. 1 and 4, the engine 1, the motor 2, and the input shaft 3A of the transmission 3 are arranged in this order when viewed from the power transmission system. The output of the machine 3 is transmitted to the drive shafts 4L and 4R via the power transmission gear 5, the differential (differential) 6 and the like, and drives the drive wheels 4W and 4W. A first clutch (input clutch) 7 is interposed between the engine 1 and the motor 2, and when the engine 1 is stopped and only the motor 2 travels, the input clutch 7 is used.
Is disengaged and the input clutch 7 is engaged when the engine 1 is operated and used as a drive source.

Further, between the motor 2 and the drive wheel 4W (here, between the transmission 3 and the differential 6),
A second clutch (output clutch) 8 is provided, and is used for power generation (battery charging), driving auxiliary machinery, etc.
When the vehicle is stopped or driven at a very low speed while operating the engine, the output clutch 8 may be disengaged or slip-coupled to disconnect the engine from the drive system of the vehicle or to absorb the rotational speed difference. Has become.

Further, the input clutch 7 and the output clutch 8
As a mechanism for controlling the engagement state of, there is provided a hydraulic control type mechanism as shown in FIG. 5, for example. That is, as shown in FIG. 5, the main bodies of the clutches 7 and 8 include a first rotating member (shaft member) 11 and a second rotating member (case) 12,
An input shaft (for example, the output shaft 1A of the engine 1 or the output shaft 3B of the transmission 3) to the clutches 7 and 8 is connected to one of the first rotating member 11 and the second rotating member 12, and the other is connected to the clutch. Output shaft to 7, 8 (eg input shaft 2 of motor 2
A and the input shaft 3A) to the transmission 3 are connected.

Further, inside the clutch 7, 8 main body,
A plurality of clutch discs 11A that rotate integrally with the first rotating member 11 and a plurality of clutch discs 12A that rotate integrally with the second rotating member 12 are alternately arranged coaxially with a viscous fluid interposed therebetween. 11A, 12
A piston 13 is provided to engage A with each other. The piston 13 is urged by a return spring 14 so as to retract toward the side where the clutch disks 11A and 12A are disengaged. A hydraulic chamber 15 is formed between the piston 13 and the second rotating member (case) 12, and when the hydraulic pressure in the hydraulic chamber 15 increases, the piston 1
3 moves forward against the return spring 14 to engage both clutch disks 11A and 12A.

Therefore, a hydraulic control mechanism 20 for adjusting the hydraulic pressure (control hydraulic pressure) in the hydraulic chamber 15 is provided. The hydraulic control mechanism 20 includes, for example, an oil pump 21 that is driven by a motor 21A and pressurizes hydraulic oil, and a pressure regulating valve 2
2, an oil passage 23 provided between the oil pump 21 and the pressure regulating valve 22, and an oil passage 24 provided between the pressure regulating valve 22 and the hydraulic chamber 15. The hydraulic pressure is adjusted by the pressure regulating valve 22 and output to output the oil in the oil passage 24 and in the hydraulic chamber 1.
The hydraulic pressure in 5 is adjusted.

The pressure regulating valve 22 is an input port 22A to which the discharge pressure (original pressure) from the oil pump 21 is constantly supplied.
And a discharge port (EX port) 22B for releasing pressure oil to the outside
And an output port 22C communicating with the oil passage 24 on the hydraulic chamber 15 side
And a valve body 22D that opens and closes each port 22A to 22C,
A solenoid (linear solenoid) 22E for adjusting the axial position of the valve body 22D is provided, and the opening degrees of the ports 22A to 22C are adjusted according to the axial position of the valve body 22D. Then, the pressure regulating valve 22 closes the EX port 22B to close the input port 22A and the output port 22.
From the maximum oil pressure state communicating with C to the minimum oil pressure state [hydraulic pressure 0 (= atmospheric pressure)] where the input port 22B is closed and the EX port 22A communicates with the output port 22C, the oil pressure of the output port 22C (that is, It is configured as a linear solenoid valve capable of linearly adjusting the hydraulic pressure in the hydraulic chamber 15. The solenoid may be a duty solenoid whose duty is controlled.

A controller (control means) 30 is provided to control the solenoid 22E and adjust the pressure by the pressure regulating valve 22. When the clutches 7 and 8 are disengaged, the controller 30 can hold the clutches 7 and 8 in a state immediately before engagement (position immediately before power transmission), in other words, when the clutches 13 and 8 are disengaged. The clutch 7 and 8 are disengaged so that the clearance (end play) between the working end (clutch disc pressing end) 13A and the clutch discs 11A and 12A is as close to 0 as possible and drag torque is not generated. Learning control means 31 for learning the hour position is provided.

In the learning control means 31, at the time of learning,
Both the clutch to be learned and the other clutch are disengaged, and the motor 2 is operated at a constant torque to perform learning while rotating the clutch element (clutch disc) on the motor side of the clutch to be learned at a minute speed. The engagement command value of the target clutch (in this embodiment, a hydraulic pressure command value for increasing the control hydraulic pressure) is gradually increased to determine the moment when the learning target clutch is engaged, and the engagement command value at this time is determined. The learning value P _CL is stored based on

For this reason, the learning control means 31 engages with the first command means 32 for issuing a command to maintain the clutch that is not the learning target in the released state, and the command to rotate the motor 2 and the clutch to be learned. Second command means 33 for issuing a command (a command for gradually increasing the engagement command value),
The rotational fluctuation upon detecting rotational fluctuation during engaging operation of the learning target clutch stores the engagement command value P _C at this time as the learned value P _CL as an indication that the clutch is engaged the storage means (first Storage means) 34 and this storage means 3
The learning value P _CL stored in 4 is corrected to a non-engagement side by a predetermined decrease correction amount (predetermined amount) α, and is learned based on the non-engagement reference command value P _CS (= P _CL −α). And a non-engagement control means 35 for controlling the non-engagement of the clutch.

Therefore, when the first clutch (input clutch) 7 is to be learned, for example, the first command means 32
The second clutch (output clutch) 8 is disengaged in response to the command, and the motor 2 is operated with a constant torque in accordance with the command from the second command means 33 to engage the first clutch 7 from the disengaged state (for example, hydraulic pressure 0). The command value (hydraulic pressure command value) is gradually increased by a predetermined engagement command value increase amount (hydraulic pressure command value increase amount) ΔP _C to gradually increase the control hydraulic pressure.

The initial value of the engagement command value (hydraulic pressure command initial value) P _{C0 at} this time is a value (P _C0 ) obtained by dividing the force (urging force) F _RS equivalent to the stroke of the return spring 14 by the piston area S. = F _RS / S). Therefore, the engagement command value first starts with the command value P _C0 that is sufficient to offset the biasing force of the return spring 14. Further, at the time of learning the first clutch 7, in order to perform accurate learning, the engine 1 that is a mechanism located on the learning target clutch side with respect to the motor 2 is stopped, or when the rotation of the motor 2 is stable. It is desirable to start learning.

As a result, in the first clutch 7, the motor 2
A clutch element that rotates integrally with the engine 1 (e.g., clutch disk 12A) and a clutch element that stops together with the engine 1 (e.g., clutch disk 11A)
Since there is a difference in rotational speed between the clutch disks 11A and 12A, when the clutch disks 11A and 12A change from the disengaged state to the engaged state, the difference in rotational speed between the clutch disks 11A and 12A becomes small. , 12A cause fluctuations in the rotational speed (rotational fluctuations).

Therefore, if attention is paid to the rotation of one of the clutch disks 11A and 12A, this rotation fluctuation can be detected, and the moment when the clutch disks 11A and 12A change from the non-engaged state to the engaged state is recognized. be able to. In this case, the moment of engagement can be more surely recognized by paying attention to the rotation of the clutch disk of the smaller mass of the rotating system [in this case, the clutch element (clutch disk 12A) that rotates integrally with the motor 2]. It has become.

Then, in this way, the clutch disc 1
The storage unit 34 stores the engagement command value (hydraulic pressure command value) P _C given at the moment when 1A and 12A change from the disengaged state to the engaged state, as a learning value P _CL . When the learning value P _CL is stored in the storage means 34 in this way, when the first clutch 7 to be learned is engaged from the disengaged state (released state), the disengagement time control means 35 controls this A decrease correction value obtained by correcting the stored learning value P _CL to the non-engagement side by a predetermined decrease correction amount α (this value is used as a reference command value for engagement control when the clutch is disengaged. The first clutch 7 is controlled by P _CS (= P _CL −α) which is a reference command value at the time of non-engagement.

By the way, the non-engagement control means 35 reduces the learning value P _CL to the non-engagement side (that is, the clutch disengagement side) by a predetermined reduction correction amount α and reduces the correction value (non-engagement). Time reference command value) P _CS (= P _CL −α), and a decrease correction value 35 C (= non-engagement reference command value) P _CS (= P _CL −α). Based on the operation control unit 35B that controls the operation of the learning target clutch (for example, the first clutch 7) based on the above, and until the rotation fluctuation of the learning target clutch (the first clutch 7) is detected during the operation control by the operation control unit 35B. When a rotational fluctuation of the learning target clutch is detected during the operation control by the predetermined amount increase correction means 35C for increasing the predetermined amount α and the operation control means 35B, the predetermined amount α at the time of detecting the rotational fluctuation is stored as the second learning value. 2 storage means 3 It is composed of a D. If the second learning value is stored in the second storage unit 35D, the decrease correction unit 35A uses the second learning value as the predetermined amount α, and stores the second learning value in the second storage unit. If the learned value is not stored, a preset value is used as the predetermined amount α.

Therefore, in the non-engagement control means 35,
The reduction correction means 35A reduces the learning value P _CL to the non-engagement side by a predetermined reduction correction amount (predetermined amount) α, and the reduction correction value (non-engagement reference command value) P _CS (= P _CL − Based on α), the operation control unit 35B controls the learning target first clutch 7 when it is not engaged.
The reduction correction amount (predetermined amount) α is a hydraulic pressure equivalent to the initial stroke of the piston 13, and its initial value is set in advance.

Further, the learning control means 31 of this embodiment is provided with an evaluation means 36 for evaluating whether or not the non-engagement reference command value P _CS is appropriate. The evaluation means 36 evaluates whether the non-engagement reference command value P _CS is too large or too small as compared with the appropriate value. Non-engagement reference command value P
The evaluation as to whether _CS is larger than the appropriate value is performed by the non-engagement control means 35 to the hydraulic pressure 0 for the learning target clutch.
Switching from the command value instantaneously disengaged when the reference command value P _CS, check to carry out the test for the presence of the step response of the learned clutch. That is, the non-engagement reference command value P _CS
If is too large, the learning target clutch is engaged by the non-engagement reference command value P _CS, so that the rotation variation occurs in the engagement element of the learning target clutch.

Therefore, if the rotation of the engaging element of the learning target clutch varies with respect to such a change in the command value, it can be determined that the non-engagement reference command value P _CS is too large than the appropriate value. In this case, the predetermined amount increase correction means 35C
Thus, for example, the decrease correction amount α is increased by a minute amount Δα, the non-engagement reference command value P _CS is decreased by a minute amount Δα, and the learning target clutch is disengaged again by the operation control means 35B as described above. The predetermined amount α at the time of detecting the rotation fluctuation of the learning target clutch at this time is stored in the second storage means 35D as the second learning value, and the decrease correction means 3
5A, the decrease correction value (non-engagement reference command value) P _CS (= P _CL −α) is calculated again based on the stored predetermined amount (second learning value) α and learning value P _CL. It is designed to evaluate whether or not this calculated value is larger than the proper value.

If the evaluation means 36 can thus evaluate that the reduction correction value (non-engagement reference command value) P _CS is not too large than the appropriate value, the non-engagement reference command value P _CS is an appropriate value. It is evaluated whether it is too small. Here, from the state in which the non-engagement control means 35 controls the non-engagement of the learning target clutch based on the non-engagement reference command value P _CS , for example, a clutch with a hydraulic pressure of about 50% is surely operated. Response time from the engagement command to the clutch engagement by issuing an engagement command according to the command value
Seeking T _RP, the response time T _RP is compared with a predetermined value T _0, if the response time T _RP is less than a predetermined value T _0, is not too small when the reference command value P _CS disengaged (suitable There is).

On the contrary, if the response time T _RP is longer than the predetermined value T ₀ or less, it is evaluated that the non-engagement reference command value P _CS is inappropriate. In this case, for example, the decrease correction amount α is reduced by a minute amount Δα ′, the non-engagement reference command value P _CS is increased by a minute amount Δα ′, and it is again determined that the value is too smaller than the appropriate value. Evaluate. As a result, the appropriate non-engagement reference command value P _CS can be reliably set.

When the second clutch (output clutch) 8 is to be learned, the first clutch (input clutch) 7 is disengaged by the command of the first command means 32 and the command of the second command means 33 is issued. The second clutch 8 is operated in a non-engaged state (for example, hydraulic pressure is 0) by operating the motor 2 with a constant torque.
On the other hand, the engagement command value (oil pressure command value) is gradually increased from the initial value P _C0 by a predetermined engagement command value increase amount (oil pressure command value increase amount) ΔP _C to gradually increase the control oil pressure. . Also during learning of the second clutch 8, in order to perform accurate learning, the vehicle that is a mechanism located on the learning target clutch side with respect to the motor 2 is stopped, or learning is performed when the rotation of the motor 2 is stable. It is desirable to start.

As a result, in the second clutch 8, the motor 2
A clutch element (for example, clutch disc 11A) that rotates integrally with the clutch element and a clutch element (for example, clutch disc 12A) that stops integrally with the drive wheels 4W of the vehicle.
Since there is a difference in rotation speed between the clutch disks 11A and 12A from the disengaged state to the engaged state, the difference in rotation speed between the clutch disks 11A and 12A becomes small. Clutch disk 11A, 1
2A causes rotation speed fluctuation (rotation fluctuation). Therefore, as in the case of the first clutch 7, and stores the rotational engagement command value at the time of change (the oil pressure command value) as a learned value P _CL, a value obtained by subtracting the decrease correction value α from the learning value P _CL non The engagement reference command value P _CS can be set.

Since the clutch control device for a hybrid vehicle as one embodiment of the present invention is configured as described above, clutch control (learning control) is performed as shown in FIGS. 2 and 3, for example. That is, as shown in FIG. 2, the first command means 32 of the learning control means 31 first puts the clutch on the side opposite to the learning target into the disengaged state (disengaged state) (step S10), and If the learning target side mechanism, that is, the first clutch 7 is a learning target, the engine 1 is stopped, and if the second clutch 8 is a learning target, the vehicle (the driving mechanism downstream of the second clutch 8 in the driving force transmission path) is stopped (step). S20).

Then, the second command means 33 rotates the motor 2 with a predetermined constant torque (step S3).
0), wait until the rotation speed of the motor 2 becomes constant through the determination in step S40. For example, it is determined that the rotation speed of the motor 2 has become constant when the rotation speed deviation of the motor 2 per unit time is equal to or smaller than a predetermined minute value for a predetermined time or longer. When the number of rotations of the motor 2 becomes constant, the actual learning control is started using the above steps S10 to S40 as a preparation part.

First, the second command means 33 outputs an initial value P _C0 as an engagement command value (hydraulic pressure command value) to the learning target clutch to start the engagement operation (step S5).
0). Since the initial value P _C0 is a value obtained by dividing the force (urging force) F _RS equivalent to the stroke of the return spring 14 by the piston area S, first, the bias of the return spring 14 can be offset to the learning target clutch. Hydraulic pressure is given.

Next, a control element for the learning target clutch (for example, a clutch disk on the motor 2 side of the learning target clutch).
It is determined whether the rotation fluctuation is detected (step S6).
0). If the rotation fluctuation is not detected, the engagement command value (hydraulic pressure command value) is increased by a predetermined engagement command value increase amount (hydraulic pressure command value increase amount).
It is increased by ΔP _C (step S70), and it is again determined whether or not the rotation fluctuation is detected (step S60).

When steps S70 and S60 are repeated, the learning target clutch is engaged and the rotation fluctuation of the engagement element of the learning target clutch can be detected. Therefore, when the rotation fluctuation is detected in this way, steps S60 to S80 are performed.
Then, the engagement command value (hydraulic pressure command value) P _C when the rotation fluctuation occurs is stored in the storage means 34 as the learning value P _CL , and then the hydraulic pressure is reduced to release the learning target clutch (step S90), first learning (learning value detection control)
To finish.

In this way, when the learning value P _CL is obtained, the reduction correcting means 35A calculates a predetermined value α from the learning value P _CL.
By subtracting the decrease correction value (non-engagement command reference value) P
It is possible to set _CS (= P _CL −α), and then evaluate whether or not this decrease correction value (non-engagement command reference value) P _CS is appropriate and decrease correction corresponding to this evaluation. The value (command reference value during non-engagement) P _CS is reset and (above, second learning) is performed.

That is, in the second learning, as shown in FIG. 3, first, as in the preparation part in the case of the first learning in FIG.
The clutch on the opposite side of the learning target is released (non-engaged state)
(Step S110), the mechanism on the learning target side of the motor 2 is stopped (step S120), the motor 2 is rotated with a predetermined constant torque (step S130), and the rotation speed of the motor 2 is determined through the determination of step S140. Wait until the value becomes constant.

When the rotation speed of the motor 2 becomes constant, the evaluation means 36 starts the evaluation process. First, the non-engagement command reference value P _CS (= P _CL −α) obtained from the learning of FIG.
Is output, and the learning target clutch is caused to make a step response by the operation control by the operation control means 35B (step S150). Then, it is determined whether or not the rotation fluctuation is detected in the control element of the learning target clutch (for example, the clutch disk on the motor 2 side of the learning target clutch) (step S1).
60).

When the rotational fluctuation is detected, the non-engagement command reference value P _CS is determined to be too large (inappropriate), and the predetermined amount increase correction means 35C increases the subtraction correction value α by a predetermined minute amount Δα. Then, the decrease correction value (non-engagement command reference value) P _CS (= P _CL −α) is changed (step S1).
70) above, the processes of steps S110 to S160 are repeated. At this time, if rotation variation occurs in the clutch to be learned, the subtraction correction value α at this time is stored in the second storage means 35D as the second learning value, and the decrease correction value (non-engagement command reference Value) Perform processing including calculation of P _CS . As a result, even when the non-engagement command reference value P _CS is given and the learning target clutch is made to respond in a step manner, the rotation fluctuation is not detected, and the non-engagement command reference value P that brings the learning target clutch into a state of just before engagement. You can get _CS .

On the other hand, if the rotation fluctuation is not detected in step S160, it is determined that the non-engagement command reference value P _CS is not too large, and the process proceeds to step S180, and the non-engagement control means 35 stores it. Learning value (correction engagement command value) P _CL
From the non-engaged state of the learning target clutch based on the above, for example, an engagement command is issued by a command value at which the clutch with a hydraulic pressure of about 50% is surely engaged, and the learning target clutch is made to respond stepwise.

Then, a response time (response) T _RP from the engagement command to the engagement of the clutch is obtained, and the response is determined by comparing the response time T _RP with a predetermined value T ₀ (step S190). Here, if the response time T _RP is the predetermined value T ₀ or less, it is evaluated that the stored learning value (corrected engagement command value) P _CL is not too small (appropriate). On the contrary, if the response time T _RP is larger than the predetermined value T ₀ or less,
It is evaluated that the stored learning value (correction engagement command value) P _CL is inappropriate, the subtraction correction value α is decreased by a predetermined minute amount Δα ′, and the non-engagement command reference value P _CS (= P _CL −α) is changed (step S200), and then steps S110 to S110 are performed.
The process of S190 is repeated.

As a result, when the non-engagement command reference value P _CS is given to make the learning target clutch step response, an appropriate response is obtained, and the non-engagement command reference value P _CS is obtained.
_{It is possible to set CS} to an appropriate value that is neither too large nor too small, that is, a value that brings the learning target clutch into a state on the verge of engagement (position immediately before power transmission). In this way, according to the clutch control device for the hybrid vehicle, the non-engagement reference command value P _CS that brings the clutch into a state on the verge of engagement and in which drag does not occur can be reliably obtained. At the time of non-engagement, by controlling the clutch based on the non-engagement reference command value P _CS , it is possible to engage the clutch with good responsiveness when the engagement command is given to the clutch. become.

Particularly, in learning for obtaining the non-engagement reference command value P _CS , the motor 2 which is easy to control the output torque gives the rotational speed difference to the clutch to perform the engaging operation, so that the clutch is stable. It is possible to reliably detect the moment of engagement by applying the generated torque, and the learning value P _CL
Further, the non-engagement reference command value P _CS can be accurately obtained. In addition, it is easy to give a minute torque to the clutch, and even for a minute torque capacity, the learning value P _CL
Further, the non-engagement reference command value P _CS can be accurately obtained.

Further, in the case of the hydraulic control clutch as in this embodiment, when the clutch is disengaged, it is possible to prevent air from entering the disengaged hydraulic circuit, so that the control accuracy can be improved. There are also advantages. Further, even if the reference command value P _CS for non-engagement is given to the clutch, dragging does not occur, so that durability of members such as the piston 13 of the clutch and power transmission efficiency do not decrease.

The present invention is not limited to the above-described embodiments, but can be implemented with various modifications without departing from the spirit of the present invention. For example, in the present embodiment, the evaluation unit 36 evaluates whether the non-engagement reference command value P _CS is too large or too small as compared with the appropriate value, but the first learning (learning value P _CL When the hydraulic pressure command value increase amount ΔP _C used at the time of detection) is appropriate (not too large),
Since the non-engagement reference command value P _CS is not too large than the appropriate value, the evaluation means 36 causes the non-engagement reference command value P _{CS to be.}
It suffices to evaluate only whether or not is smaller than an appropriate value.

Further, if the hydraulic pressure command value increase amount ΔP _C is appropriately given by, for example, setting the hydraulic pressure command value increase amount ΔP _C sufficiently small, the result of the first learning also becomes highly reliable.
In such a case, the evaluation by the evaluation means 36 may be omitted. Further, when the non-engagement reference command value P _CS is too large or too small as compared with the appropriate value, the non-engagement reference command value P _CS is changed by the decrease correction amount α as in the present embodiment. Although it is not a substantially different method, although it is carried out by changing the change, the disengagement reference command value P _CS , which was not appropriate, is increased or decreased by a small amount to obtain an appropriate disengagement reference command value P _CS. May be requested.

The setting of the initial value P _C0 and the initial decrease correction amount α is not limited to that of this embodiment. Further, in the present embodiment, the hydraulic control clutch is described as an example,
The present invention can also be applied to an electromagnetic clutch.

[0059]

As described in detail above, according to the clutch control device for a hybrid vehicle of the present invention as set forth in claim 1, since the motor is used as the clutch drive source, it is possible to operate in a stable state and in an extremely low speed rotation state. The combined command value can be learned, and the learning accuracy can be improved. As a result, the torque transmission starting point of the clutch can always be accurately determined regardless of the change with time of the clutch. In particular, the first clutch is slip-controlled when starting an engine that was in a stopped state while the motor is running or running at a very low speed while the motor is running, but since the torque transmission starting point of the clutch is set accurately. It is possible to perform optimum slip control. Further, when applied to the hydraulic control clutch, air can be prevented from entering the hydraulic circuit when not engaged, so that control accuracy can be improved and dragging does not occur. Therefore, it is possible to suppress deterioration of durability of members such as the clutch itself and its control member, and deterioration of power transmission efficiency.

According to the clutch control device for a hybrid vehicle of the present invention as defined in claim 2, when the engagement command is issued when the first clutch or the second clutch is disengaged, the reduction correction value is controlled as a command value. As a result, the clutch is securely held in a state of being on the verge of engagement without dragging, and when the clutch engagement command is issued, the clutch can be engaged more responsively. . Further, since the learning value can be obtained by the stable rotation while giving the differential rotation to the clutch by rotationally driving the motor, and further, the learning value can be obtained while slightly changing the decrease correction value, the learning can be performed. The reduction correction value based on the value can be obtained with high accuracy, and when the clutch is disengaged, the clutch can be more accurately maintained in the state of just before engagement, the control accuracy can be further improved, and dragging may occur. Absent. Therefore, it is possible to further suppress the deterioration of the durability of the clutch itself and its control members and the like, and the deterioration of the power transmission efficiency.

According to the clutch control device for a hybrid vehicle of the present invention as set forth in claim 3, the clutch can be more accurately held in a state of being on the verge of engagement, and the engagement responsiveness of the clutch can be more surely improved. Even when applied to the hydraulic control clutch, it is possible to more reliably prevent air from entering the hydraulic circuit when not engaged, so that it is possible to further improve control accuracy. The present invention according to claim 4
According to the clutch control device for hybrid vehicles, the output torque
It is possible to apply a rotational speed difference to the clutch with a motor that is easy to control
Since the engaging operation is performed by the
Reliable detection of the moment of engagement by applying torque
Therefore, the learning value can be obtained with high accuracy. Well
It is also easy to give a slight torque to the clutch.
Therefore, the learning value can be obtained accurately even for a small torque capacity.
Can be turned on.

[Brief description of drawings]

FIG. 1 is a block diagram showing a main configuration of a clutch control device for a hybrid vehicle as an embodiment of the present invention.

FIG. 2 is a flowchart for explaining control contents by a clutch control device for a hybrid vehicle as an embodiment of the present invention.

FIG. 3 is a flowchart illustrating control contents by a clutch control device for a hybrid vehicle as an embodiment of the present invention.

FIG. 4 is a schematic diagram illustrating a configuration of a hybrid vehicle according to the present invention, for explaining the problems of the present invention.

FIG. 5 is a schematic diagram illustrating a problem of the present invention and showing a clutch mechanism according to the present invention.

[Explanation of symbols] 1 engine 2 motor 3 transmission 4W drive wheel 7 1st clutch (input clutch) 8 2nd clutch (output clutch) 20 Hydraulic control mechanism 30 controller (control means) 31 Learning control means 32 First command means 33 Second command means 34 storage means (first storage means) 35 Non-engagement control means 35A Decrease correction means 35B operation control means 35C predetermined amount increase correction means 35D Second storage means 36 Evaluation means

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁷ Identification code FI B60K 6/04 730 B60K 17/04 ZHVG 17/04 ZHV F16D 25/14 640J (56) References JP-A-10-14171 (JP) , A) JP-A-11-127502 (JP, A) JP-A-2000-35122 (JP, A) Jitsugaku Kohei 7-28427 (JP, Y2) (58) Fields investigated (Int.Cl. ⁷ , DB name) ) F16D 48/00-48/12 B60K 6/02-6/06 B60K 17/04 F16H 59/00-61/12 F16H 61/16-61/24 F16H 63/40-63/48 B60L 11/02- 11/14 B60K 41/00-41/28

Claims (4)

(57) [Claims] 1. A hybrid vehicle including an engine, a motor, and drive wheels, a first clutch interposed between the engine and the motor, and an interface between the motor and the drive wheels. And a control means for controlling the motor, the first clutch, and the second clutch by a command signal. The control means includes one of the first clutch and the second clutch. A first command means for maintaining the clutch in a released state; and a second command for rotationally driving the motor and engaging the other clutch of the first clutch and the second clutch.
A hybrid vehicle, comprising: an instruction unit; and a storage unit that stores an engagement command value at this time as a learning value when a rotation fluctuation of the other clutch is detected during an engagement operation of the other clutch. Clutch control device. 2. Reduction control means for obtaining a reduction correction value obtained by reducing the learning value stored in the storage means to a release side by a predetermined amount as a reference command value at the time of engagement control, and based on the reduction correction value. And an operation control means for controlling the operation of the other clutch, a predetermined amount increase correction means for increasing the predetermined amount until the rotational fluctuation of the other clutch is detected during the operation control by the operation control means, and the operation control Second storage means for storing the predetermined amount as a second learning value when the rotation fluctuation is detected during operation control by the means, and the reduction correction means stores the second correction value in the second storage means. If the second learning value is stored, the second learning value is used as the predetermined amount, and if the second learning value is not stored in the second storage means, a preset value is used as the predetermined amount. It is used as. Hybrid vehicle clutch control device of the mounting. 3. The control means controls the other clutch by using the reduction correction value as a reference command value at the time of engagement control by the operation control means, and the other clutch is engaged from the time when the engagement command is issued. 3. The method according to claim 2, further comprising: an evaluation unit that obtains a response time up to and determines whether the decrease correction value is appropriate as a reference command value during engagement control based on the response time. A clutch control device for the hybrid vehicle described. 4. The control means controls the motor with a constant torque.
Operate the clutch on the motor side of the clutch to be learned.
While rotating the element at a very small speed,
Gradually increase the engagement command value to obtain the learning target clutch
Determines the moment of engagement, and based on the engagement command value at this time
4. The learning value is stored as a result of the learning.
The clutch control of the hybrid vehicle according to any one of 1.
apparatus.