JP2013160360A - Vehicle drive control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vehicle drive control device configured to improve comfort of a driver at the time of engagement/disengagement of a clutch of an automatic transmission, when the clutch is in a transient engagement state.SOLUTION: At the time of engagement/disengagement of clutches C1-C4 of an automatic transmission 3, when the clutches C1-C4 are in transient engagement states, an ECU 100 controls a capacitance coefficient C of a torque inverter 2 to linearly change.

Description

  The present invention relates to a vehicle drive control device including a torque converter that amplifies torque, and an automatic transmission having a clutch that transmits or disconnects power output via the torque converter to a drive wheel. The present invention relates to a vehicle drive control device that controls the capacity coefficient of the vehicle.

  Conventionally, a torque converter, which is a fluid coupling, is arranged between an engine and an automatic transmission. The torque converter is configured to amplify the engine torque at the time of starting the vehicle and transmit the amplified torque to the automatic transmission, and to absorb shock at the time of shifting and sudden acceleration / deceleration (for example, Patent Documents). 1).

Conventionally, a capacity coefficient C [10 ⁻⁶ × Nm / rpm ² ] is used as a parameter representing the performance of the torque converter. The capacity coefficient C [10 ⁻⁶ × Nm / rpm ² ] of the torque converter is determined by, for example, changing the shift lever of the shift device mounted on the vehicle from the “N” (neutral) range to the “D” (drive) range. When the speed ratio e between the engine speed Ne [rpm] and the turbine speed Nt [rpm] of the torque converter changes from “1” to “0” (that is, the automatic transmission) When the clutch is in a transitional state), a peak point exists immediately before the speed ratio e becomes “0” (upward convex curve relationship).

Further, as a method of calculating the load Tc [Nm] of the torque converter, first, a speed ratio e (Nt / Ne) between the engine speed Ne [rpm] and the turbine speed Nt [rpm] of the torque converter is calculated. . Next, the capacity coefficient C [10 ⁻⁶ × Nm / rpm ² ] of the torque converter corresponding to the calculated speed ratio e (Nt / Ne) is determined from the performance curve diagram (map) of the torque converter. The torque converter capacity coefficient C [10 ⁻⁶ × Nm / rpm ² ] is multiplied by the square of the engine speed Ne [rpm] (torque converter load (Tc) = capacity coefficient (C) × engine speed). Squared (Ne ² )).

Further, as a method of calculating the estimated load [Nm] of the torque converter, the load Tc [Nm] of the torque converter described above is calculated based on the target engine speed [rpm] of the engine and the estimated turbine speed [rpm] of the torque converter. It is calculated by the formula (Tc = C × Ne ² ) to be calculated. When the calculated estimated load [Nm] of the torque converter is substantially equal to the actual load (actual load) [Nm] of the torque converter (when the deviation amount (deviation) is small). The engine rotation and the turbine rotation of the torque converter maintain a stable state.

JP-A-8-261314

  However, when the clutch of the automatic transmission is engaged or disengaged, if the clutch is in a transitional state (when the speed ratio e changes), it is caused by variations in response of parts or hydraulic pressure. The magnitude of the estimated load of the torque converter and the magnitude of the actual load of the torque converter greatly deviate due to deviation of the clutch engagement instruction of the automatic transmission from the ECU and the actual clutch engagement timing. Engine rotation and turbine rotation of the torque converter may increase. For this reason, there are problems that the ride comfort of the driver is deteriorated and the wear amount of the clutch of the automatic transmission is increased.

  The present invention has been devised in view of the above problems, and improves the ride comfort of the driver when the clutch engagement state is in a transitional state when the clutch of the automatic transmission is engaged or released. Another object of the present invention is to provide a vehicle drive control device capable of reducing the amount of wear of a clutch of an automatic transmission.

  As means for solving the above-described problems, the vehicle drive control device of the present invention is configured as follows.

  That is, the vehicle drive control device according to the present invention is premised on the provision of a torque converter that amplifies torque and an automatic transmission that has a clutch that transmits or disconnects the power output via the torque converter to the drive wheels. And when the clutch of the automatic transmission is engaged or disengaged, the capacity coefficient for controlling the capacity coefficient of the torque converter to change linearly when the clutch is in a transitional state. Control means are provided.

  According to the vehicle drive control device having such a configuration, when the clutch of the automatic transmission is engaged or disengaged, the engine speed and the turbine speed of the torque converter when the clutch is in a transitional state. When the speed ratio changes, the amount of deviation between the actual load (actual load) of the torque converter and the estimated load of the torque converter can be reduced. As a result, an increase in engine rotation and turbine rotation of the torque converter can be suppressed, so that the ride comfort of the driver can be improved and the amount of wear of the clutch of the automatic transmission can be reduced.

  According to the vehicle drive control device of the present invention, when the clutch of the automatic transmission is engaged or disengaged, the ride comfort of the driver is improved and the automatic transmission is improved when the clutch is in a transitional state. The amount of wear of the clutch of the machine can be reduced.

It is a schematic block diagram which shows an example of the vehicle by which the control apparatus of the vehicle of this invention is mounted. It is a block diagram which shows the structure of control systems, such as ECU. It is a flowchart which shows the procedure of the capacity | capacitance coefficient control of a torque converter when the engagement state of a clutch is in a transition state. It is a timing chart which shows the specific example of the capacity coefficient control of the torque converter by this embodiment. It is a timing chart which shows the case where the capacity coefficient control of the torque converter by a comparative example is not performed. It is a performance curve figure (map) which shows the capacity coefficient change with respect to the speed ratio of the torque converter by this embodiment, and the capacity coefficient change with respect to the speed ratio of the torque converter by a comparative example.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a schematic configuration diagram illustrating an example of a vehicle equipped with a vehicle drive control device according to an embodiment of the present invention. The vehicle is equipped with an engine 1, a torque converter 2, an automatic transmission 3, an ECU 100, a hydraulic control circuit 300 (see FIG. 2), and the like.

-Engine-
A crankshaft 11 that is an output shaft of the engine 1 is connected to an input shaft of the torque converter 2 as shown in FIG. The rotational speed of the crankshaft 11 (engine rotational speed Ne [rpm]) is detected by the engine rotational speed sensor 201.

  The amount of air taken into the engine 1 is adjusted by an electronically controlled throttle valve 12. The opening degree of the throttle valve 12 (throttle opening degree) is detected by a throttle opening degree sensor 202.

  The throttle opening of the throttle valve 12 is driven and controlled by the ECU 100. Specifically, the ECU 100 optimizes intake air according to the operating state of the engine 1 such as the engine speed detected by the engine speed sensor 201 and the accelerator pedal depression amount (accelerator opening) of the driver (driver). The throttle opening of the throttle valve 12 is controlled so that the amount (target intake air amount) is obtained.

-Torque converter-
The torque converter 2 includes a pump impeller 21 on the input shaft side, a turbine runner 22 on the output shaft side, a stator 23 that develops a torque amplification function, and a one-way clutch 24. The torque converter 2 is configured to transmit power between the pump impeller 21 and the turbine runner 22 via a fluid.

  The torque converter 2 is provided with a lockup clutch 25 that directly connects the input side and the output side. By engaging the lock-up clutch 25, the pump impeller 21 and the turbine runner 22 rotate integrally. The turbine speed Nt of the torque converter 2 is detected by the turbine speed sensor 203. Engagement or release of the lockup clutch 25 of the torque converter 2 is controlled by the hydraulic control circuit 300 and the ECU 100.

-Automatic transmission-
As shown in FIG. 1, the automatic transmission 3 includes a double pinion type first planetary gear device 31, a single pinion type second planetary gear device 32, and a single pinion type third planetary gear device 33. This is a planetary gear type transmission.

  The sun gear S1 of the first planetary gear device 31 is selectively connected to the input shaft 30 via the clutch C3. The sun gear S1 is selectively coupled to the housing via the one-way clutch F2 and the brake B3, and is prevented from rotating in the reverse direction (the direction opposite to the rotation of the input shaft 30). The carrier CA1 of the first planetary gear unit 31 is selectively connected to the housing via the brake B1, and is always prevented from rotating in the reverse direction by the one-way clutch F1 provided in parallel with the brake B1. The ring gear R1 of the first planetary gear device 31 is integrally connected to the ring gear R2 of the second planetary gear device 32, and is selectively connected to the housing via the brake B2.

  The sun gear S2 of the second planetary gear device 32 is integrally connected to the sun gear S3 of the third planetary gear device 33, and is selectively connected to the input shaft 30 via the clutch C4. The sun gear S2 is selectively connected to the input shaft 30 via the one-way clutch F0 and the clutch C1, and is prevented from rotating in the opposite direction relative to the input shaft 30.

  The carrier CA2 of the second planetary gear device 32 is integrally connected to the ring gear R3 of the third planetary gear device 33, is selectively connected to the input shaft 30 via the clutch C2, and via the brake B4. And selectively coupled to the housing. The carrier CA2 is always prevented from rotating in the reverse direction by the one-way clutch F3 provided in parallel with the brake B4. The carrier CA3 of the third planetary gear device 33 is integrally connected to the output shaft 34, and power is transmitted from the output shaft 34 to drive wheels (not shown). The rotational speed of the output shaft 34 is detected by the output shaft rotational speed sensor 204.

  In the automatic transmission 3 described above, the gears (shift speeds) are set by engaging or releasing the clutches C1 to C4, the brakes B1 to B4, the one-way clutches F0 to F3, and the like in a predetermined state. Engagement or disengagement of the clutches C1 to C4 and the brakes B1 to B4 is controlled by a hydraulic pressure control circuit 300 (see FIG. 2).

  The hydraulic control circuit 300 is provided with a linear solenoid valve, an on / off solenoid valve, and the like. Then, it is possible to control the engagement or disengagement of the clutches C1 to C4 and the brakes B1 to B4 of the automatic transmission 3 by controlling excitation or non-excitation of these solenoid valves and switching the hydraulic circuit. Excitation or non-excitation of the linear solenoid valve and the on / off solenoid valve of the hydraulic control circuit 300 is controlled by a solenoid control signal (instructed hydraulic signal) from the ECU 100.

-ECU-
As shown in FIG. 2, the ECU 100 includes a CPU 101, a ROM 102, a RAM 103, a backup RAM 104, and the like.

  In the ROM 102, in addition to control related to basic driving of the vehicle, when the clutches C1 to C4 of the automatic transmission 3 are engaged or disengaged, the engagement states of the clutches C1 to C4 are in a transient state. In this case, various programs including a program for executing capacity coefficient control for controlling the capacity coefficient C of the torque converter 2 are stored. The specific contents of this capacity coefficient control will be described later.

  The CPU 101 executes arithmetic processing based on various control programs and maps stored in the ROM 102. The RAM 103 is a memory that temporarily stores calculation results in the CPU 101, data input from each sensor, and the like. The backup RAM 104 is a nonvolatile memory that stores data to be saved when the engine 1 is stopped.

  The CPU 101, ROM 102, RAM 103, and backup RAM 104 are connected to each other via a bus 106 and to an interface 105.

  An interface 105 of the ECU 100 includes an engine speed sensor 201, a throttle opening sensor 202, a turbine speed sensor 203, an output shaft speed sensor 204, an accelerator opening sensor 205 that detects an accelerator pedal opening, and a shift position sensor 206. A brake pedal sensor 207 and an in-vehicle acceleration sensor 208 that detects the longitudinal acceleration of the vehicle are connected, and signals from these sensors are input to the ECU 100.

  The ECU 100 executes various controls of the engine 1 including the opening control of the throttle valve 12 of the engine 1 based on the output signals of the various sensors described above.

  The ECU 100 outputs a lockup clutch control signal to the torque converter 2. Based on this lock-up clutch control signal, the engagement pressure of the lock-up clutch 25 (see FIG. 1) is controlled. The ECU 100 also outputs a solenoid control signal (hydraulic command signal) to the hydraulic control circuit 300 of the automatic transmission 3. Based on this solenoid control signal, the linear solenoid valve and the on / off solenoid valve of the hydraulic control circuit 300 are controlled. Then, the clutches C1 to C4, the brakes B1 to B4, the one-way clutches F0 to F3, etc. of the automatic transmission 3 are engaged or engaged in a predetermined state so as to constitute a predetermined transmission gear stage (1st to 6th). To be released.

  Further, the ECU 100 executes the following “capacity coefficient control”.

-Capacity coefficient control-
Hereinafter, with respect to the capacity coefficient control executed by the ECU 100, the flowchart shown in FIG. 3, the timing chart shown in FIG. 4, and the relationship between the speed coefficient e of the torque converter 2 shown in FIG. (Curve diagram). In the timing chart shown in FIG. 4, on the vertical axis, the target engine speed [rpm], the estimated turbine speed [rpm] of the torque converter 2, the load [Nm] of the torque converter 2 (actual load (solid line) and The estimated load (broken line)) and the change in the capacity coefficient C [10 ⁻⁶ × Nm / rpm ² ] of the torque converter 2 are shown. Further, the horizontal axis of FIG. 4 indicates the elapsed time. In FIG. 6, the horizontal axis indicates the speed ratio e (Nt / Ne) between the turbine speed Nt [rpm] of the torque converter 2 and the engine speed [rpm] Ne, and the vertical axis indicates the capacity coefficient of the torque converter 2. C [10 ⁻⁶ × Nm / rpm ² ] is shown.

  First, as shown in FIG. 3, in step ST1, for example, the driver (driver) switches the shift lever of the shift device mounted on the vehicle from the “N” (neutral) range to the “D” (drive) range. Each of the clutches C1 to C4 of the automatic transmission 3 is engaged (or released) when the operation is performed (or when an operation of switching from the “D” (drive) range to the “N” (neutral) range) is performed. Thus, it is determined whether or not each of the clutches C1 to C4 of the automatic transmission 3 is in a transient state. Specifically, the clutch C1 of the automatic transmission 3 is based on a solenoid control signal (hydraulic command signal) output from the ECU 100 to the hydraulic control circuit 300 (see FIG. 2) at time T (0) shown in FIG. Control (instruction) of each engagement or release of .about.C4 is performed. At this time, the ECU 100 determines that the engagement state of each of the clutches C1 to C4 of the automatic transmission 3 is in a transient state (positive determination: Yes), and advances the process to step ST2. If a negative determination (No) is made in step ST1, the process proceeds to step ST5.

  Note that the target engine speed (for example, about 600 [rpm]) and the estimated turbine speed (for example, about 600 [rpm]) of the torque converter 2 are determined by the ECU 100 at the clutch C1 of the automatic transmission 3 at time T (0). The predetermined number of rotations is maintained until a predetermined time elapses (from time T (0) to time T (1)) after the respective engagement or release control of .about.C4 is performed. . That is, the time point at which the ECU 100 controls the clutches C1 to C4 at time T (0) and the time point at which the target engine speed and the estimated turbine speed of the torque converter 2 start to decrease at time T (1) are predetermined. The time is shifted (delayed). Then, between the time T (1) and the time T (4), the target engine speed and the estimated turbine speed of the torque converter 2 gradually decrease. Thereafter, at time T (4), the target engine speed [rpm] decreases to about 500 [rpm], and the estimated turbine speed [rpm] of the torque converter 2 decreases to about 0 [rpm]. Further, after the time T (4), the target engine speed [rpm] and the estimated turbine speed [rpm] of the torque converter 2 are substantially constant (the target engine speed = about 500 [rpm], and the torque converter 2 is estimated). Turbine rotational speed = about 0 [rpm]).

  The magnitude of the actual load (solid line) of the torque converter 2 gradually increases from time T (0) to time T (2) and from time T (2) to time T (3). Has a convex curve relationship between the two. Moreover, the magnitude of the actual load (solid line) of the torque converter 2 is substantially constant after time T (3).

Next, as shown in FIG. 3, in step ST2, a capacity coefficient C [10 ⁻⁶ × Nm / rpm ² ] at the convergence destination of the torque converter 2 is calculated. The capacity coefficient C at the convergence destination of the torque converter 2 is the magnitude of the capacity coefficient Ce of the torque converter 2 at time T (3) shown in FIG. More specifically, as shown in FIG. 6, the capacity coefficient Ce corresponds to the speed ratio “0” of the torque converter 2. Thereafter, as shown in FIG. 3, the process proceeds to step ST3.

Next, in step ST3, a monotonously increasing process of the capacity coefficient C [10 ⁻⁶ × Nm / rpm ² ] of the torque converter 2 is performed. Specifically, as shown in FIG. 4, the ECU 100 detects the capacity coefficient C [10 of the torque converter 2 from time T (2) (capacity coefficient Cs) to time T (3) (capacity coefficient Ce). ⁻⁶ × Nm / rpm ² ] is controlled so as to increase linearly and monotonously. More specifically, as shown in FIG. 6, the ECU 100 switches the shift lever of the shift device mounted on the vehicle from the “N” (neutral) range to the “D” (drive) range by the driver (driver). When the operation is performed, the capacity coefficient C of the torque converter 2 increases linearly and monotonically from the capacity coefficient Cs to the capacity coefficient Ce as the speed ratio changes from “1” to “0”. Control (solid line in FIG. 6). The capacity coefficient Cs corresponding to the speed ratio 1 of the torque converter 2 (solid line in FIG. 6) according to the present embodiment is the capacity coefficient corresponding to the speed ratio 1 of the torque converter 2 (broken line in FIG. 6) according to a comparative example described later. It is the same size as Cs. Further, the capacity coefficient Ce corresponding to the speed ratio 0 of the torque converter 2 (solid line in FIG. 6) according to the present embodiment is the capacity coefficient corresponding to the speed ratio 0 of the torque converter 2 (broken line in FIG. 6) according to a comparative example described later. It is the same size as Ce. Thereafter, as shown in FIG. 3, the process proceeds to step ST4.

Next, in step ST4, the estimated load [Nm] of the torque converter 2 is calculated. Specifically, the estimated load [Nm] of the torque converter 2 is based on the capacity coefficient C [10 ⁻⁶ × Nm / rpm ² ] controlled so as to increase linearly and monotonically in step ST3. The estimated load [Nm] = capacity coefficient C × the square of the engine target speed [rpm ² ]. Thus, time T (2) from the time T (3) shown in FIG. 4 the estimated load of the torque converter 2 in until [Nm] (dashed line), the capacity coefficient C [10 ^-6 × increasing linearly monotonously As with Nm / rpm ² ], it increases monotonically linearly. And as shown in FIG. 3, it returns to step ST1 and repeats a process.

  In step ST1, it is determined whether or not each of the clutches C1 to C4 is in a transient state by engaging or disengaging each of the clutches C1 to C4 of the automatic transmission 3, and a negative determination is made. When (No) is made, it is determined that the engaged state of each of the clutches C1 to C4 is not a transient state, and the process proceeds to step ST5.

Next, in step ST5, the capacity coefficient C [10 ⁻⁶ × Nm / rpm ² ] of the torque converter 2 when the engagement state of each of the clutches C1 to C4 is not a transient state is calculated. The capacity coefficient C of the torque converter 2 is a performance curve diagram (map) of the torque converter 2 based on the speed ratio e calculated from the target engine speed [rpm] and the estimated turbine speed [rpm] of the torque converter 2. ) (See FIG. 6). Then, the process proceeds to step ST4.

Next, in step ST4, the estimated load [Nm] of the torque converter 2 is calculated. At this time, the torque converter 2 is based on the capacity coefficient C [10 ⁻⁶ × Nm / rpm ² ] of the torque converter 2 when the engagement state of each of the clutches C1 to C4 calculated in step ST5 is not a transient state. The estimated load [Nm] = capacity coefficient C × the square of the engine target speed [rpm ² ]. And it returns to step ST1 and repeats a process.

  Next, referring to the present embodiment shown in FIG. 4 and the comparative example shown in FIG. 5, when each engagement state of the clutches C1 to C4 of the automatic transmission 3 is in a transient state, “capacity coefficient control” ”Will be described.

  In the torque converter 2 according to the comparative example shown in FIG. 5, when each of the clutches C1 to C4 of the automatic transmission 3 is engaged or disengaged, each of the clutches C1 to C4 is in a transient state. Between the time T (2) (capacity coefficient Cs) and the time T (4) (capacity coefficient Ce), the engine target is not performed without performing the capacity coefficient control that monotonically increases the capacity coefficient C according to the present embodiment. The speed ratio e and the capacity coefficient C are calculated from the rotational speed [rpm] and the estimated turbine rotational speed [rpm] of the torque converter 2. As a result, the capacity coefficient C of the torque converter 2 according to the comparative example has an upward convex curve relationship from the time T (2) to the time T (4), unlike the case where the capacity coefficient control according to the present embodiment is performed. And has a characteristic that a peak point exists in the vicinity of time T (3).

  Further, in the torque converter 2 according to the comparative example shown in FIG. 5, the estimated load [Nm] (broken line) of the torque converter 2 has an upwardly convex curve relationship similarly to the characteristic of the capacity coefficient C of the torque converter 2. ing. Here, in the torque converter 2 according to the comparative example, when the engagement state of each of the clutches C <b> 1 to C <b> 4 of the automatic transmission 3 changes, the estimated load of the torque converter 2 due to variations in vehicle components and hydraulic response, etc. [Nm] (broken line) is in a state shifted by a predetermined time with respect to the actual load [Nm] (solid line) of the torque converter 2. For this reason, the magnitude of the estimated load [Nm] (dashed line) of the torque converter 2 is equal to the actual load [Nm] (solid line) of the torque converter 2 from time T (3) to time T (4). The load balance between the estimated load [Nm] of the torque converter 2 and the actual load [Nm] of the torque converter 2 becomes excessive. As a result, engine rotation and turbine rotation of the torque converter 2 increase.

  On the other hand, in the torque converter 2 according to the present embodiment shown in FIG. 4, the time T (3) shown in FIG. 4 is increased by linearly monotonically increasing between the capacity coefficient Cs and the capacity coefficient Ce by the capacity coefficient control. ) To time T (4), the magnitude of the estimated load [Nm] (dashed line) of the torque converter 2 and the magnitude of the actual load [Nm] (solid line) of the torque converter 2 can be made to substantially coincide with each other. Therefore, unlike the torque converter 2 according to the comparative example, the load balance becomes almost zero, and it is possible to suppress the engine rotation and the turbine rotation of the torque converter 2 from increasing.

  As described above, according to the capacity coefficient control in the present embodiment, when the clutches C1 to C4 of the automatic transmission 3 are engaged or disengaged, the engagement states of the clutches C1 to C4 are in a transient state. , The actual load (actual load) of the torque converter 2 and the estimated load of the torque converter 2 when the speed ratio e between the engine speed and the turbine speed of the torque converter 2 changes. The deviation (divergence) from can be reduced. Accordingly, an increase in engine rotation and turbine rotation of the torque converter can be suppressed, so that the ride comfort of the driver is improved and the wear amount of each of the clutches C1 to C4 of the automatic transmission 3 is reduced.

  The present invention can be applied to, for example, a drive control device for a vehicle that is a torque converter mounted on an automobile and performs capacity coefficient control for controlling the capacity coefficient of the torque converter to change linearly. .

2 Torque converter 3 Automatic transmission 100 ECU
201 Engine speed sensor 203 Turbine speed sensor 300 Hydraulic control circuit C1, C2, C3, C4 Clutch

Claims (1)

In a vehicle drive control device comprising: a torque converter that amplifies torque; and an automatic transmission having a clutch that transmits or disconnects power output via the torque converter to a drive wheel.
Capacity coefficient control means for controlling the capacity coefficient of the torque converter to change linearly when the clutch is in a transient state when the clutch of the automatic transmission is engaged or disengaged. A vehicle drive control apparatus comprising:

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