JP4722280B2 - Automatic clutch control device for vehicle - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an automatic clutch control device applied to a vehicle capable of executing traveling stability control.
[0002]
[Prior art]
In recent years, a traveling stability control device, so-called VDC (Vehicle Dynamic Control), has been put into practical use in order to increase traveling stability of a vehicle. This is to control the engine or the brake independently of the vehicle driving operation system or away from the driver's operation and to control the driving state of the vehicle in a stable direction when a predetermined condition is satisfied during vehicle driving. .
[0003]
[Problems to be solved by the invention]
By the way, conventionally, when the VDC and the automatic clutch are combined, the control of holding the clutch position at the current position is performed during the VDC control (travel stability control) in order to prevent the clutch control from interfering. That is, when the VDC control is started, if the clutch is engaged, the contact is maintained, and if the clutch is disconnected, the disconnection is maintained.
[0004]
However, there is a case where it is desired to increase the wheel output torque by increasing the engine output during VDC control. At this time, there is no problem if the clutch engagement is maintained. There is a problem that speed control cannot be executed. In this case, only the braking direction can be controlled by brake control.
[0005]
Therefore, an object of the present invention is to enable wheel drive torque to be increased even when VDC control is started from a clutch disengaged state.
[0006]
[Means for Solving the Problems]
The present invention relates to a vehicle having a traveling stability control device for controlling an engine or a brake independently of a vehicle driving operation system and controlling a traveling state of the vehicle in a stable direction. Clutch control means for connecting / disconnecting control, and when the engine or brake is controlled independently from the vehicle driving operation system by the travel stability control device , the automatic clutch is in the disconnected state in the clutch control means. In this case, until the wheel stability control device requests to increase the wheel driving torque, the automatic clutch is disengaged and held, and only the braking direction is controlled by the brake control by the vehicle stability control device. When there is a request for increasing the wheel drive torque, connection control means is provided for bringing the automatic clutch into a connected state.
[0007]
As a result, even when the VDC control is started from the clutch disengaged state, when the wheel drive torque increase request is made, the clutch is connected and the wheel drive torque can be increased.
[0008]
Here, the automatic clutch executes a fluid pressure supply / discharge to / from the fluid pressure actuator based on a control signal of the friction type clutch, a fluid pressure actuator that drives the clutch to connect / disconnect, and a control signal of the clutch control means. It is preferable to provide fluid pressure supply / discharge means.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings.
[0010]
FIG. 1 is a configuration diagram of a vehicle to which the present invention is applied. This vehicle is equipped with an automatic clutch, and in particular, a so-called selective auto clutch device capable of manual connection / disconnection. The selective auto clutch device uses a normal friction clutch as the clutch 1 and is configured to be manually connected / disconnected by the manual connection / disconnection means 2 or automatically connected / disconnected by the automatic connection / disconnection means 3. The figure shows a state in which the clutch 1 is connected and no means is operated.
[0011]
The clutch 1 is stroked in the connecting / disconnecting direction by reciprocating the clutch fork 4 by a slave cylinder 5 (which constitutes the “fluid pressure actuator” of the present invention). The slave cylinder 5 is supplied with hydraulic pressure (fluid pressure) as a clutch operating force from the intermediate cylinder 6. The intermediate cylinder 6 sends a hydraulic pressure corresponding to the hydraulic pressure supplied from the master cylinder 7 or the hydraulic pressure source 8 to the slave cylinder 5. The master cylinder 7 generates a hydraulic pressure corresponding to the depression amount (operation amount) of the clutch pedal 9 and sends it to the intermediate cylinder 6. The hydraulic source 8 includes an electric motor 10, a hydraulic pump 11, a check valve 32, electromagnetic valves 30 and 31, and a relief valve 13, and the motor 10 and electromagnetic valves 30 and 31 are driven and controlled by a clutch control unit (referred to as a clutch ECU) 14. To supply and discharge hydraulic pressure. Oil as a working fluid is stored in the oil tank 15.
[0012]
The solenoid valves 30 and 31 are duty-controlled by the clutch ECU 14, and here, normally closed ones, that is, ones that are closed when OFF and opened when ON are used. The solenoid valves 30 and 31 are used for clutch connection. The solenoid valves 30 and 31 have different oil discharge port diameters. Therefore, three types of clutch engagement speeds (low speed, medium speed, or high speed) can be selected by changing the combination of ON / OFF of the solenoid valves 30 and 31. The relief valve 13 is for fail-safe opening when the hydraulic pressure rises abnormally, and is normally closed.
[0013]
In this configuration, the manual connection / disconnection of the clutch 1 is performed as follows. First, when the clutch pedal 9 is depressed from the illustrated state, hydraulic pressure is generated in the master cylinder 7. Then, as shown by the solid line arrow, the two pistons 16 and 17 inside the intermediate cylinder 6 are pushed simultaneously and in the same direction, and the oil pressure corresponding to the pedal depression amount is supplied from the intermediate cylinder 6 to the slave cylinder 5. Then, in the slave cylinder 5, the internal piston 18 is pushed, whereby the clutch fork 4 is pushed, and the clutch 1 is operated to the dividing side by an amount corresponding to the pedal depression amount. When the return operation of the clutch pedal 9 is performed, the oil is returned as indicated by the broken line arrow, and the clutch 1 is operated to the connection side. At this time, the pistons 16 and 17 of the intermediate cylinder 6 are pushed back to the normal positions by the return spring 37. In this way, manual connection / disconnection is achieved, and the manual connection / disconnection means 2 is configured by the clutch pedal 9, the master cylinder 7, the intermediate cylinder 6, and the slave cylinder 5.
[0014]
A method for automatically connecting and disconnecting the clutch 1 will be described later.
[0015]
The clutch stroke (clutch position) is always detected by the clutch stroke sensor 19. The clutch stroke sensor 19 is a potentiometer that is operated by the clutch fork 4 via a link 36. The clutch stroke sensor 19 outputs a larger voltage as the clutch stroke is divided. A hydraulic switch 33 is provided at the outlet of the intermediate cylinder 6. This is turned ON when the outlet pressure of the intermediate cylinder 6 rises to a certain set value. The signals from the sensor 19 and the switch 33 are sent to the clutch ECU 14.
[0016]
This vehicle is equipped with a normal transmission (manual transmission) 20. The transmission 20 is mechanically coupled to the shift lever 23 via a mechanical coupling means 57 such as a link or a wire cable, and is subjected to a shift operation in conjunction with the shift lever operation by the driver.
[0017]
The shift lever 23 is a part of the shift lever device 21. That is, the shift lever device 21 includes a shift lever 23, a shift knob 22 that forms a grip portion thereof, and a knob switch 62 built in the shift knob 22. The shift knob 22 can be slightly swung (swinged) in the shift direction with respect to the shift lever 23, and is normally held at the center position by a built-in spring, but is swung when a predetermined shift force is applied. 62 is turned on.
[0018]
The transmission 20 includes a shift stroke sensor 34 for detecting a shift direction stroke of the internal shifter lever, a neutral switch 24 for detecting that the shifter lever is in the neutral position, and a shift lever lever in the select direction. A select stroke sensor 35 for detecting a stroke is provided. The clutch ECU 14 detects the current gear stage (current gear stage) of the transmission 20 based on signals from these sensors and switches.
[0019]
Here, an automatic connection / disconnection method of the clutch 1 will be described. It is assumed that the driver gives a shift force to the shift knob 22 in order to change speed while traveling at a predetermined gear stage. Then, the shift knob 22 is slightly swung and the knob switch 62 is turned on. With this as a signal, the clutch ECU 14 sends a clutch disconnection command to the automatic connection / disconnection means 3 and specifically starts the motor 10. Then, the hydraulic pump 11 is activated to generate hydraulic pressure, and the hydraulic pressure pushes the check valve 32 open to the intermediate cylinder 6 as indicated by the solid line arrow. The intermediate cylinder 6 pushes the pistons 16 and 17 in the separating direction. Thereby, the piston 17 on the outlet side further pressurizes the oil on the outlet side and supplies it to the slave cylinder 5. When this happens, the piston 18 of the slave cylinder 5 pushes the clutch fork 4 and separates the clutch 1.
[0020]
The clutch ECU 14 stops the motor 10 when the clutch stroke sensor 19 recognizes the clutch completion. Thereafter, the check valve 32 holds the hydraulic pressure and the clutch 1 is held off. During this time, the driver continuously operates the shift lever, and the transmission 20 is put into the next gear stage.
[0021]
The clutch ECU 14 recognizes the gear-in from the signals of the shift stroke sensor 34 and the select stroke sensor 35 and simultaneously sends a clutch engagement command to the automatic connection / disconnection means 3 to start connection control of the clutch 1. Specifically, at least one of the solenoid valves 30 and 31 is turned on, the hydraulic pressure is discharged from the slave cylinder 5 as indicated by the broken line arrow, the clutch fork 4 is returned, and the clutch 1 is connected. At this time, the optimum ON / OFF combination of the solenoid valves 30 and 31 is selected in consideration of the clutch connection state, the accelerator depression, the engine and the vehicle operation state, and the duty control to these solenoid valves. Is done. As a result, the clutch is connected at the optimum speed.
[0022]
Thus, the clutch 1, the hydraulic power source 8, the intermediate cylinder 6 and the slave cylinder 5 constitute the automatic clutch of the present invention, and the clutch ECU 14 serves as the clutch control means of the present invention. The slave cylinder 5 constitutes the fluid pressure actuator of the present invention, and the hydraulic pressure source 8 and the intermediate cylinder 6 constitute the fluid pressure supply / discharge means of the present invention.
[0023]
Switching between manual connection and automatic connection / disconnection is performed by a changeover switch 25 provided in the passenger compartment. An accelerator opening sensor 39 is provided for detecting the amount of depression of the accelerator pedal 38, that is, the accelerator opening. The accelerator opening sensor 39 is a potentiometer and outputs a voltage signal proportional to the accelerator opening. An accelerator idle switch 40 is provided near the accelerator pedal, and is turned on when the accelerator pedal 38 is in the idle area and turned off when the accelerator pedal 38 is depressed more than the idle area. The outputs of the sensor 39 and the switch 40 are sent to the clutch ECU 14.
The engine 43 is a diesel engine in which a fuel injection pump 44 and an electronic governor 41 are combined, and a fuel injection amount, fuel injection timing, and the like are electronically controlled based on a control signal from an engine ECU (not shown). Although the engine is electronically controlled as described above, a common rail fuel injection device or an electronically controlled gasoline engine can be used in addition to this example. The engine 43 is provided with an engine speed sensor 45 for detecting the engine speed, and the output is sent to the clutch ECU 14.
[0024]
Further, the transmission 20 is provided with an output shaft rotation sensor 63 for detecting the output shaft rotation speed, and the clutch ECU 14 converts the vehicle speed based on the output of the sensor 63.
[0025]
In this vehicle, a running stability control means is provided for controlling the engine or the brake independently from the vehicle driving operation system and controlling the running state of the vehicle in a stable direction. Specifically, a travel stability control control unit (referred to as a VDC control unit) 66 is provided, and when a predetermined condition is met, the VDC control unit 66 can control the electronic governor 41 or the driver regardless of whether the driver operates the accelerator pedal or the brake pedal. Control the brake and bring the vehicle in a stable direction. The VDC control unit 66 and the clutch ECU 14 can communicate with each other via a bus cable or the like. Although not shown in the drawings, the brake can naturally be automatically controlled in this way.
[0026]
In normal engine control, the fuel injection amount is increased or decreased according to the increase or decrease of the accelerator opening, but is increased or decreased during VDC control regardless of the accelerator opening. Similarly, the brake force is normally adjusted by a brake pedal operation by the driver, but during the VDC control, the brake force is controlled by the VDC control unit 66 regardless of the pedal operation.
[0027]
Next, the contents of the clutch control according to the present invention will be described with reference to FIG. The clutch ECU 14 is given information from the VDC control unit 66 regarding constant running stability control (referred to as VDC control). Based on this information, the clutch ECU 14 determines in step 101 whether the VDC control is currently in progress. If it is determined that VDC control is not being performed, the routine proceeds to step 103 where the clutch is set to normal control. When it is determined that the VDC control is being performed, the process proceeds to step 102.
[0028]
In step 102, it is determined whether or not there has been a wheel drive torque increase request from the VDC control unit 66. When there is a request, the routine proceeds to step 104 where the clutch is brought into the engaged state. That is, the clutch is automatically connected when the current clutch is disengaged or retained, and the current state is maintained when the current clutch is engaged or retained. On the other hand, when there is no request, the routine proceeds to step 105 and the transition from disengagement of the clutch to contact is prohibited. That is, as in the past, the clutch is held in its current position regardless of whether the clutch is in a connected or disconnected state.
[0029]
As described above, according to the above control, the clutch is always connected when the wheel drive torque increase request is made during the VDC control. Therefore, even if the clutch is disconnected at the start of the VDC control, the wheel drive torque increase request is made. If there is, the clutch can be connected and the engine output can be transmitted to the wheels (drive wheels). In the VDC control, the fuel injection amount is increased, the engine output is increased, this is transmitted to the wheels, the wheel driving torque is increased, and the desired VDC control or speed increase control can be executed.
[0030]
Thus, here, the program for executing steps 101, 102, 104 stored in the clutch ECU 14 constitutes the connection control means of the present invention.
[0031]
It should be noted that the present invention can take various other embodiments. For example, the clutch can be a wet multi-plate clutch or the like, and the “friction type clutch” of the present invention includes such a clutch. The “fluid pressure actuator” can be modified, and a fluid pressure other than oil pressure (for example, pneumatic pressure) can be used.
[0032]
【The invention's effect】
In short, according to the present invention, an excellent effect is exhibited that the wheel driving torque can be increased even when the VDC control is started from the clutch disengaged state.
[Brief description of the drawings]
FIG. 1 is an overall configuration diagram of a vehicle to which the present invention is applied.
FIG. 2 is a flowchart showing details of clutch control according to the present invention.
[Explanation of symbols]
1 Clutch 5 Slave cylinder 8 Hydraulic source 10 Electric motor 11 Hydraulic pump 14 Clutch control unit 30, 31 Solenoid valve 43 Engine 66 Travel stability control control unit

Claims (2)

An automatic clutch and a connection / disconnection control of the automatic clutch in a vehicle having a traveling stability control device for controlling an engine or a brake independently of a vehicle driving operation system and controlling a traveling state of the vehicle in a stable direction. And when the engine or brake is controlled independently from the vehicle driving operation system by the travel stability control device, the clutch control means has a clutch control means when the automatic clutch is disengaged. Until the driving stability control device requests wheel drive torque increase, the automatic clutch is kept in a disengaged state and only the braking direction is controlled by the braking control by the driving stability control device. vehicle when there is a torque increase request, characterized in that a connection control means for the automatic clutch in a connected state Automatic clutch control device.   The automatic clutch includes a friction-type clutch, a fluid pressure actuator that connects and disconnects the clutch, and a fluid pressure supply that supplies and discharges fluid pressure to and from the fluid pressure actuator based on a control signal of the clutch control means. The automatic clutch control device for a vehicle according to claim 1, further comprising a discharge unit.

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