JP2019035464A - Controller of vehicular transmission - Google Patents

Abstract

To provide a controller of a vehicular transmission capable of surely avoiding engine stall or vehicle shock, in a case of detecting a signal for posture control start.SOLUTION: An ECU is configured to, in a case of detecting a signal indicating a posture controller starts posture control (YES in step S2), when an engine speed is less than a predetermined engine speed, and engine torque is less than predetermined engine torque (YES in step S3), control opening of a discharge port at the maximum to open a lock-up clutch (step S5).SELECTED DRAWING: Figure 2

Description

  The present invention relates to a control device for a vehicle transmission.

  In a vehicle transmission mounted on a vehicle such as an automobile, the vehicle is provided with a lock-up clutch for directly connecting an input-side rotating body and an output-side rotating body of a torque converter provided between an engine and an automatic transmission. There is a transmission.

  In such a vehicle transmission, if a strong braking force is applied to the wheels while the lockup clutch is engaged, the braking force may be transmitted to the engine via the lockup clutch, which may cause an engine stall. is there. The braking force of the vehicle is generated not only when the braking operation is performed by the driver, but also by the turning behavior stabilization control device for stabilizing the turning behavior of the vehicle.

  In order to solve such a problem, conventionally, when it is determined that the stabilization operation of the vehicle turning behavior is started, a technique is known in which the lockup clutch is preferentially released (see Patent Document 1). . Since the lockup clutch is preferentially released when the start of the stabilization operation of the vehicle turning behavior is determined, the one disclosed in Patent Document 1 reduces the throttle valve opening or the engine rotation due to the braking operation. Even if a change occurs, it is possible to prevent a shock caused by the change.

Japanese Patent Laid-Open No. 10-38067

  However, since the control described in Patent Document 1 simply controls to release the lock-up clutch and does not adjust the release mode, engine stall and vehicle shock are not necessarily generated. It was not always possible to prevent it. For example, in the case of the one disclosed in Patent Document 1, it may take time to complete the release of the lock-up clutch, so that engine stall may not be prevented. I could not.

  The present invention has been made paying attention to the above-described problems, and is a vehicle transmission that can reliably avoid engine stalls and vehicle shocks when a signal for starting attitude control is detected. The object is to provide a control device.

  The present invention relates to a lockup clutch that connects and disconnects an engine and a transmission, a lockup control valve that switches an oil path to supply hydraulic oil pressure to an engagement side oil chamber of the lockup clutch, and generation of the engine An engine speed sensor that detects an engine speed to be detected, and a vehicle transmission control device that is mounted on a vehicle and that detects a signal from an attitude control device that controls the attitude of the vehicle, the lockup control valve Has a discharge port for discharging hydraulic oil from the engagement side oil chamber, and detects an engine torque calculation unit for calculating engine torque generated by the engine and a signal for starting attitude control by the attitude control device The engine speed is less than a predetermined engine speed, and the engine torque is less than a predetermined engine torque. Can is characterized in that it comprises a lock-up control unit for the opening of the exhaust port controls the maximum opening the lock-up clutch.

  As described above, according to the present invention, when a posture control start signal is detected, engine stall and vehicle shock can be reliably avoided.

FIG. 1 is a configuration diagram of a vehicle including a control device for a vehicle transmission according to an embodiment of the present invention. FIG. 2 is a flowchart for explaining a lockup clutch release mode switching operation by the control device for a vehicle transmission according to an embodiment of the present invention. FIG. 3 is a lockup release mode switching map referred to by the ECU in the lockup clutch release mode switching operation of FIG. FIG. 4 is a timing chart illustrating an example of a lockup clutch switching mode when the lockup clutch release mode switching operation of FIG. 2 is performed. FIG. 5 is a timing chart for explaining an example of the transition of the degree of engagement of the lockup clutch when the lockup clutch release mode switching operation of FIG. 2 is performed.

  A control device for a vehicle transmission according to an embodiment of the present invention includes a lockup clutch that connects and disconnects an engine and a transmission, and oil that supplies hydraulic pressure of hydraulic oil to an engagement-side oil chamber of the lockup clutch. A vehicle transmission that detects a signal from a posture control device that is mounted on a vehicle and that controls a posture of the vehicle, and includes a lockup control valve that switches a road, an engine rotational speed sensor that detects an engine rotational speed generated by the engine The lockup control valve has a discharge port that discharges hydraulic oil from the engagement side oil chamber, and includes an engine torque calculation unit that calculates engine torque generated by the engine, and a posture by the posture control device When a control start signal is detected, the engine speed is less than the predetermined engine speed and the engine torque is the predetermined engine torque. When it is full it is characterized in that it comprises a lock-up control unit to open the lock-up clutch the opening of the exhaust port is controlled to maximum. Thereby, the control apparatus for the vehicle transmission according to the embodiment of the present invention can reliably avoid the engine stall and the vehicle shock when the attitude control start signal is detected.

  A vehicle control apparatus according to an embodiment of the present invention will be described below with reference to the drawings.

  As shown in FIG. 1, the vehicle 10 includes an engine 20, a transmission 30, wheels 12, an attitude control device 40, and an ECU (Electronic Control Unit) 50 as a control unit that comprehensively controls the vehicle 10. , And.

  The engine 20 is formed with a plurality of cylinders. In this embodiment, the engine 20 is configured to perform a series of four strokes including an intake stroke, a compression stroke, an expansion stroke, and an exhaust stroke for each cylinder.

  The engine 20 is provided with an engine speed sensor 27. The engine speed sensor 27 detects the engine speed generated by the engine 20 based on the rotational position of a crankshaft (not shown), and sends a detection signal to the ECU 50. Send to.

  The transmission 30 shifts the rotation transmitted from the engine 20 and drives the wheels 12 via the drive shaft 11. The transmission 30 includes a torque converter 32, a lockup clutch 33, a transmission mechanism and a differential mechanism (not shown).

  The torque converter 32 amplifies torque by converting the rotation transmitted from the engine 20 into torque via hydraulic oil. When the lock-up clutch 33 is released, power is transmitted between the engine 20 and the speed change mechanism via hydraulic oil.

  When the lockup clutch 33 is engaged (at the time of engagement), the input side and the output side of the torque converter 32 are directly connected. Thus, the lockup clutch 33 connects and disconnects the engine 20 and the transmission 30.

  The transmission mechanism is composed of CVT (Continuously Variable Transmission), and automatically performs a variable transmission steplessly by a set of pulleys around which a metal belt is wound. The ECU 50 controls the change of the gear ratio in the transmission 30 and the engagement or release of the lockup clutch 33.

  Note that the speed change mechanism may be an automatic transmission (so-called step AT) that performs a step change using a planetary gear mechanism. The differential mechanism is connected to the left and right drive shafts 11 and transmits the power shifted by the speed change mechanism to the left and right drive shafts 11 so as to be differentially rotatable.

  The transmission 30 may be an AMT (Automated Manual Transmission). The AMT is an automatic transmission that automatically shifts by adding an actuator to a manual transmission having a parallel shaft gear mechanism. When the transmission 30 is an AMT, the transmission 30 is provided with a dry single-plate clutch instead of the torque converter 32.

  The transmission 30 may be a DCT (Dual Clutch Transmission). DCT is a kind of stepped automatic transmission, has two gears, and each has a clutch.

  The posture control device 40 suppresses unstable behavior of the vehicle such as skidding when the vehicle posture is disturbed by sudden steering operation for sudden road surface change or danger avoidance, etc. Is a device that performs control so as to secure the vehicle posture and stabilize the posture of the vehicle. The attitude control device 40 is also called a skid prevention device, ESC (Electronic Stability Control), or ESP (Electronic Stability Program). At the start of control by the attitude control device 40, the attitude control device 40 generates a control start signal, and the ECU 50 detects this control start signal.

  The transmission 30 includes a lockup control circuit 100 that controls engagement / release of the lockup clutch 33. The control circuit and mechanism related to engagement / release of the lock-up clutch 33 are the same as those in the prior art, and detailed description thereof will be omitted. However, engagement / release of the lock-up clutch 33 is performed on the engagement side oil of the torque converter 32. This is performed by the hydraulic pressure difference between the chamber 33A and the release side oil chamber 33B.

  The transmission 30 also includes a lockup control valve 101 that supplies hydraulic oil to the engagement side oil chamber 33A of the lockup clutch, and a discharge that discharges the hydraulic oil from the engagement side oil chamber 33A that the lockup control valve 101 has. A port 111 is provided. The ECU 50 controls the engagement / release of the lock-up clutch 33 by adjusting the opening degree of the discharge port 111.

  The ECU 50 is a computer that includes a CPU (Central Processing Unit), a RAM (Random Access Memory), a ROM (Read Only Memory), a flash memory for storing backup data, an input port, and an output port. It is composed of units.

  The ROM of this computer unit stores programs for causing the computer unit to function as the ECU 50, along with various constants, various maps, and the like. That is, when the CPU executes a program stored in the ROM using the RAM as a work area, these computer units function as the ECU 50 in this embodiment.

  Various sensors including the engine speed sensor 27 described above are connected to the input port of the ECU 50.

  Various control objects including the engine 20 and the transmission 30 are connected to the output port of the ECU 50. The ECU 50 controls various control objects based on information obtained from various sensors. Further, the ECU 50 calculates an engine torque generated by the engine 20. ECU50 comprises the engine torque calculation part in this invention.

  Further, the ECU 50 controls the lockup control circuit 100 of the transmission 30 to engage or release the lockup clutch 33. In the present embodiment, the ECU 50 adjusts the release speed and the like by adjusting the opening degree of the discharge port 111 when releasing the lockup clutch 33. ECU50 comprises the lockup control part in this invention.

  Here, when the wheel 12 is braked by the control of the attitude control device 40, a sudden and large braking force may act on the wheel 12. In such a case, there is a possibility that the engine speed may rapidly decrease before the lockup clutch 33 is completely released, resulting in an engine stall. Further, when both the engine speed and the engine torque are relatively small, engine stall is likely to occur as compared to when both are relatively large.

  Therefore, when the ECU 50 detects the attitude control start signal from the attitude control device 40, the ECU 50 opens the discharge port 111 when the engine speed is less than the predetermined engine speed and the engine torque is less than the predetermined engine torque. The lockup clutch 33 is released by controlling the degree to the maximum.

  On the other hand, when both the engine speed and the engine torque are relatively large, the risk of engine stall is less than when both are relatively small, but a shock is generated when the lockup clutch 33 is released. And vibration is likely to occur.

  Therefore, when the ECU 50 detects the attitude control start signal from the attitude control device 40, when the engine speed is equal to or higher than the predetermined engine speed and the engine torque is equal to or higher than the predetermined engine torque, the lockup clutch 33 is Control is performed to change from the fastening state to the releasing state.

  At this time, the ECU 50 is configured so that the engine speed is less than the predetermined engine speed and the engine torque is less than the predetermined engine torque so that the time during which the lockup clutch 33 is in the slip state is a predetermined time. The opening degree of the discharge port 111 is made small.

  Further, when the ECU 50 detects the attitude control start signal from the attitude control device 40 and the engine speed is equal to or higher than the predetermined engine speed and the engine torque is equal to or higher than the predetermined engine torque, the ECU 50 and the engine speed The larger the torque is, the slower the release speed of the lockup clutch 33 is.

  The lockup clutch release mode switching operation by the ECU 50 of the vehicle 10 configured as described above will be described with reference to the flowchart shown in FIG. This lock-up clutch release mode switching operation is always performed during system startup.

  In FIG. 2, the ECU 50 determines whether or not the lockup clutch 33 is engaged (step S1). Here, the engagement of the lock-up clutch 33 means that the degree of engagement of the lock-up clutch 33 is 100%. The ECU 50 ends the current operation when the lockup clutch 33 is not engaged.

  When the lockup clutch 33 is engaged in step S1, the ECU 50 determines whether or not an attitude control start signal (denoted as an attitude stabilization signal in the figure) is detected (step S2). When the ECU 50 has not detected the attitude control start signal, the ECU 50 ends the current operation.

  When the attitude control start signal is detected in step S2, the ECU 50 determines whether or not the region C is in the lockup release mode switching map of FIG. 3 (step S3).

  Here, in the lockup release mode switching map of FIG. 3, the region composed of the engine speed and the engine torque is divided into a region C in which release of the lockup clutch 33 is completed faster than usual, and a release of the lockup clutch 33. It is divided into a region D that is completed at a normal speed.

  In the lockup release mode switching map, region C is a region where the engine speed is less than the predetermined engine speed and the engine torque is less than the predetermined engine torque.

  In the lockup release mode switching map, the region D is a region where the engine speed is equal to or higher than the predetermined engine speed, or the engine torque is equal to or higher than the predetermined engine torque. This region D is further divided into a region D1, a region D2, and a region D3.

  Region D1 is a region where the engine speed is equal to or higher than the predetermined engine speed and the engine torque is lower than the predetermined engine torque. The region D2 is a region where the engine speed is less than the predetermined engine speed and the engine torque is equal to or greater than the predetermined engine torque.

  Region D3 is a region where the engine speed is equal to or higher than the predetermined engine speed and the engine torque is equal to or higher than the predetermined engine torque.

  When the ECU 50 is not in the area C in step S3, that is, in the area D, the ECU 50 releases the lockup clutch 33 at the release speed Vd (step S4), and ends the current operation.

  On the other hand, in the case of the region C in step S3, the ECU 50 releases the lockup clutch 33 at the release speed Vc (step S5) and ends the current operation. In this step S5, the ECU 50 opens the lockup clutch 33 by controlling the opening degree of the discharge port 111 to the maximum.

  Here, the release speed Vc> the release speed Vd. When releasing the lockup clutch 33 at the release speed Vc, the release of the lockup clutch 33 is completed earlier than at the release speed Vd.

  The release speed Vd is set to be divided into a release speed Vd1 corresponding to the area D1, a release speed Vd2 corresponding to the area D2, and a release speed Vd3 corresponding to the area D3. The release speed Vd1 and the release speed Vd2 are set equal, and the release speed Vd3 is set smaller than the release speed Vd1 and the release speed Vd2.

  Therefore, the release speed Vd1 and the release speed Vd2 are lower than the release speed Vc, and the release speed Vd3 is lower than the release speed Vd1 and the release speed Vd2.

  With reference to the timing chart of FIG. 4, the transition of the vehicle state when the lockup clutch release mode switching operation is performed will be described. In FIG. 4, the vertical axis indicates the engine speed, the turbine speed, the presence / absence of the attitude control start signal, and the release speed of the lockup clutch 33. The turbine rotational speed means the rotational speed of the rotating element on the output side in the torque converter 32.

  As shown in FIG. 4, when the attitude control start signal changes from OFF to ON at time t1, the lockup clutch release speed is changed from the normal release speed Vd to the high release speed Vc in order to prevent engine stall. Is done.

  Next, transition of the degree of engagement of the lockup clutch 33 when the lockup clutch release mode switching operation is performed will be described with reference to the timing chart of FIG. In FIG. 5, the vertical axis represents the degree of engagement of the lockup clutch 33 (hereinafter simply referred to as the degree of engagement).

  As shown in FIG. 5, at time t10, the degree of engagement is 100%, and the lockup clutch 33 is completely engaged.

  Thereafter, at time t11, the ECU 50 detects a posture control start signal, the lockup clutch 33 is controlled to the disengagement side, and the degree of engagement starts to decrease.

  At this time, when the engine speed and the engine torque are in the region C of FIG. 3, the degree of engagement decreases at the release speed Vc. On the other hand, in the region D3 of FIG. 3, the degree of engagement decreases at the release speed Vd3.

  Since the release speed Vc is a speed at which the lockup clutch 33 is released at a high speed, the degree of engagement is 0% earlier at the release speed Vc than at the release speed Vd3. That is, the release of the lockup clutch 33 is completed earlier at the release speed Vc than at the release speed Vd3.

  On the other hand, in the case of the release speed Vd3, the degree of engagement becomes 0% later than in the case of the release speed Vc. In FIG. 5, the engagement degree is 0% at time t13.

  In FIG. 5, the slip start position is the degree of engagement at which slip starts when the degree of engagement is reduced from 100%. In other words, when the degree of engagement is smaller than the slip start position, the lockup clutch 33 is in the slip state, and the input side rotating element (pump impeller) and the output side rotating element (turbine runner) of the torque converter 32 rotate relative to each other. The time E on the horizontal axis represents the time during which the lockup clutch 33 is in the slip state. This time E becomes longer as the release speed Vd3 is smaller.

  As described above, in this embodiment, the lockup control valve 101 has the discharge port 111 that discharges the hydraulic oil from the engagement side oil chamber 33A. Further, the ECU 50 calculates an engine torque generated by the engine 20. When the ECU 50 detects the attitude control start signal from the attitude control device 40, the ECU 50 opens the discharge port 111 if the engine speed is less than the predetermined engine speed and the engine torque is less than the predetermined engine torque. The lockup clutch 33 is released by controlling the degree to the maximum.

  Thus, when the attitude control start signal from the attitude control device 40 is detected, if the engine speed is less than the predetermined engine speed and the engine torque is less than the predetermined engine torque, the discharge port 111 is opened. The degree is controlled to the maximum, and the lockup clutch 33 is released. For this reason, the release of the lock-up clutch 33 is completed quickly, so that the engine stall can be prevented.

  As a result, the engine stall or the shock of the vehicle 10 can be reliably avoided when the attitude control start signal is detected.

  In the present embodiment, when the ECU 50 detects the attitude control start signal from the attitude control device 40, when the engine speed is equal to or higher than the predetermined engine speed and the engine torque is equal to or higher than the predetermined engine torque, Control is performed so that the lockup clutch 33 changes from the engaged state to the released state. Then, the ECU 50 discharges more than when the engine speed is less than the predetermined engine speed and the engine torque is less than the predetermined engine torque so that the time during which the lockup clutch 33 is in the slip state is a predetermined time. The opening degree of the port 111 is reduced.

  As a result, when the engine speed is equal to or higher than the predetermined engine speed and the engine torque is equal to or higher than the predetermined engine torque, the discharge port 111 is opened so that the time during which the lockup clutch 33 is in the slip state is a predetermined time. The degree is reduced.

  For this reason, the lockup clutch 33 changes from the engaged state to the released state through a slip state for a predetermined time. As a result, it is possible to prevent a shock from occurring in the lockup clutch 33 when the lockup clutch 33 is released, and to prevent the vehicle 10 from vibrating due to the shock of the lockup clutch 33.

  In the present embodiment, when the ECU 50 detects the attitude control start signal from the attitude control device 40, when the engine speed is equal to or higher than the predetermined engine speed and the engine torque is equal to or higher than the predetermined engine torque, The release speed of the lockup clutch 33 is decreased as the engine speed and the engine torque are increased.

  Accordingly, the higher the engine speed and the engine torque, the slower the release speed of the lockup clutch 33. Therefore, the engine speed and the engine torque can be reduced while the lockup clutch 33 is in the slip state.

  As a result, it is possible to prevent a shock from occurring in the lockup clutch 33 when the lockup clutch 33 is released, and to prevent the vehicle 10 from vibrating due to the shock of the lockup clutch 33.

  While embodiments of the invention have been disclosed, it will be apparent to those skilled in the art that changes may be made without departing from the scope of the invention. All such modifications and equivalents are intended to be included in the following claims.

DESCRIPTION OF SYMBOLS 10 Vehicle 20 Engine 27 Engine speed sensor 30 Transmission 33 Lockup clutch 33A Engagement side oil chamber 50 ECU (engine torque calculation part, lockup control part)
101 Lock-up control valve 111 Discharge port

Claims (3)

A lock-up clutch that connects and disconnects the engine and the transmission;
A lockup control valve that switches an oil passage so as to supply hydraulic oil pressure to the engagement side oil chamber of the lockup clutch;
An engine speed sensor for detecting the engine speed generated by the engine;
A control device for a vehicle transmission that detects a signal from an attitude control device that controls the attitude of a vehicle,
The lockup control valve has a discharge port for discharging hydraulic oil from the engagement side oil chamber,
An engine torque calculator for calculating an engine torque generated by the engine;
When the attitude control start signal is detected by the attitude control device, when the engine speed is less than the predetermined engine speed and the engine torque is less than the predetermined engine torque, the opening degree of the discharge port is maximized. And a lockup control unit that controls the release of the lockup clutch to release the lockup clutch. The lockup control unit
When detecting a posture control start signal by the posture control device,
When the engine speed is equal to or higher than a predetermined engine speed and the engine torque is equal to or higher than the predetermined engine torque, the lockup clutch is controlled to change from an engaged state to a released state;
More than when the engine speed is less than the predetermined engine speed and the engine torque is less than the predetermined engine torque so that the time during which the lock-up clutch is in the slip state is a predetermined time. 2. The control device for a vehicle transmission according to claim 1, wherein the opening is reduced. The lockup control unit
When detecting a posture control start signal by the posture control device,
When the engine speed is equal to or higher than the predetermined engine speed and the engine torque is equal to or higher than the predetermined engine torque, the higher the engine speed and the engine torque, the slower the release speed of the lockup clutch. The control device for a vehicle transmission according to claim 2.

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