WO2020026717A1

WO2020026717A1 - Slip control device for torque converter

Info

Publication number: WO2020026717A1
Application number: PCT/JP2019/027076
Authority: WO
Inventors: 博周
Original assignee: ジヤトコ株式会社; 日産自動車株式会社
Priority date: 2018-08-02
Filing date: 2019-07-09
Publication date: 2020-02-06
Also published as: JP2022001765A

Abstract

This slip control device for a torque converter is provided with a calculating means (51) for calculating a target slip rotational speed of a lockup clutch (20) on the basis of a driving state of a vehicle, a calculating means (53A) for calculating a slip torque capacity of the lockup clutch (20) from a feed-forward control quantity based on the target slip rotational speed, and a feedback control quantity based on the target slip rotation speed and an actual slip rotational speed, a calculating means (59) for calculating an estimated engine torque by subjecting a torque signal from an engine (1) to a correction process using a gain, and a calculating means (58) for calculating an engagement command pressure of the torque converter (20) from the estimated engine torque and the slip torque capacity, and is also provided with a gain modifying means (60) for increasing the gain by a prescribed amount if the rate of change over time in the torque signal is equal to or greater than a first prescribed value as a result a vehicle acceleration operation.

Description

Slip control device for torque converter

The present invention relates to a slip control device for a torque converter mounted on a vehicle.

スリップ A slip control device has been developed that controls the engagement capacity of a lock-up clutch so that the actual slip rotation between input and output elements of a torque converter that transmits rotation from a prime mover (engine) converges to a target slip rotation.

For example, Patent Document 1 discloses that a target slip rotation of a torque converter is obtained from a driving state of a vehicle, a slip rotation command value for making the actual slip rotation coincide with the target slip rotation is calculated, and the total performance data of the prime mover is calculated from the driving state of the vehicle. A motor output torque is estimated based on the map, a lock-up clutch engagement pressure command value corresponding to the slip rotation command value is calculated from the motor output torque estimated value and the slip rotation command value, and the lock-up clutch A technique for controlling the fastening pressure is disclosed.

Further, in Patent Document 1, a slip rotation gain is obtained from a turbine rotation of a torque converter, a target converter torque is obtained by dividing a slip rotation command value by a slip rotation gain, and the target converter torque is subtracted from an estimated motor output torque value. It is also disclosed that a target lock-up clutch engagement capacity is determined by the above-described method, and the lock-up clutch is controlled based on the target engagement capacity.

By the way, in the vehicle equipped with the slip control device of the torque converter, when the accelerator pedal is depressed, the lock-up capacity becomes too small and the engine speed is increased too much, or when the accelerator pedal is depressed. It has been found during the development of the device by the present inventors that the lock-up capacity becomes excessive and a longitudinal acceleration shock occurs in the vehicle.

The present invention has been made in view of such a problem, and when an engine torque transiently changes due to depression and return of an accelerator pedal, an appropriate slip control is performed to generate an excessive engine speed up-speed. It is an object of the present invention to provide a torque converter slip control device capable of suppressing the occurrence of shock of a vehicle or a vehicle.

JP 2000-97333 A

In order to achieve the above object, a slip control device for a torque converter according to the present invention is provided in a vehicle, and detects a slip state of a torque converter having a lock-up clutch interposed between an engine and a stepped automatic transmission. A control device for controlling, a target slip rotation calculating means for calculating a target slip rotation speed of the lock-up clutch based on an operation state of the vehicle, a feedforward control amount based on the target slip rotation speed, and A slip torque capacity calculating means for calculating a slip torque capacity of the lock-up clutch from a feedback control amount based on a target slip speed and an actual slip speed; and correcting the estimated engine torque by correcting the engine torque signal by a gain. Estimated engine torque calculating means for calculating; An engagement command pressure calculating means for calculating an engagement command pressure of the lock-up clutch from the estimated engine torque and the slip torque capacity, wherein a time change rate of the torque signal is set to a first predetermined value by an accelerator operation of the vehicle. A gain changing means is provided for increasing the gain by a predetermined amount when the gain exceeds the value.

The gain changing means preferably stops increasing the gain when the rate of change of the torque signal falls below a second predetermined value smaller than the first predetermined value during the increase of the gain.
It is preferable that the gain changing unit stops the process of increasing the gain when a predetermined time has elapsed after increasing the gain.
It is preferable that the predetermined amount is a predetermined constant value.
It is preferable that the predetermined amount is set to a larger value as the time change rate of the accelerator operation amount is larger.
It is preferable that a gain change prohibiting unit that prohibits an increase in the gain is provided during a shift of the stepped automatic transmission.

According to the present invention, when the torque signal of the engine suddenly changes with the operation of the accelerator pedal, the gain for calculating the estimated engine torque is increased from the torque signal. The influence of the delay of the torque on the actual engine torque can be suppressed, and the engagement command pressure of the lock-up clutch can be optimized. As a result, it is possible to suppress the occurrence of excessive engine speed up when the accelerator pedal is depressed and the occurrence of longitudinal acceleration shock of the vehicle when the accelerator pedal is released.

1 is a system diagram showing a main part of a drive system and a control system of a vehicle to which a slip control device for a torque converter according to an embodiment of the present invention is applied. 1 is a block diagram of a main part of a slip control device for a torque converter according to an embodiment of the present invention. 5 is a time chart for explaining control by the slip control device of the torque converter according to one embodiment of the present invention, wherein (a) shows a case where the present control is not applied, and (b) shows a case where the present control is applied. . 4 is a flowchart illustrating control by a slip control device for a torque converter according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the embodiments described below are merely examples, and there is no intention to exclude various modifications and application of technology not explicitly described in the following embodiments. Each configuration of the following embodiments can be variously modified and implemented without departing from the spirit thereof, and can be selected or appropriately combined as needed.

[1. Overall system configuration]
FIG. 1 is a system diagram showing a main part of a drive system and a control system of a vehicle to which a slip control device for a torque converter according to the present embodiment is applied.
As shown in FIG. 1, the drive system of the vehicle includes an engine (internal combustion engine) 1 as a drive source, a torque converter 2, a transmission mechanism 3, a power transmission system 7 downstream of the transmission mechanism 3 in a power transmission direction, And a drive wheel (not shown) downstream of the power transmission direction.

The automatic transmission 10 is configured by housing the torque converter 2 and the transmission mechanism 3 in the transmission case 10A. In FIG. 1, a portion (mainly the engine 1) on the upstream side in the power transmission direction with respect to the torque converter 2 and a portion between the torque converter 2 and a friction engagement element 31 described later (a turbine described later of the torque converter 2). The inertia masses of the runner 24 (including the runner 24) and the portion downstream of the friction engagement element 31 in the power transmission direction are indicated by simple blocks A, B, and C.

The torque converter 2 is a starting element having a torque increasing function, and includes a pump impeller 23 connected to the engine output shaft 11 via a converter housing 22, a turbine runner 24 connected to the torque converter output shaft 21, and A stator 25 provided via a one-way clutch (not shown) is a component. In this embodiment, when the torque increasing function is not required, the lock-up clutch 20 that can directly connect the engine output shaft 11 (= torque converter input shaft) and the torque converter output shaft 21 is provided.

The transmission mechanism 3 employs a stepped transmission mechanism that achieves a plurality of forward speeds and reverse speeds. Each shift speed is achieved by selectively engaging a plurality of friction engagement elements 31 such as a clutch or a brake. For example, when the vehicle starts moving forward, the friction engagement element 31 that achieves the first gear is engaged, and when the vehicle starts traveling backward, the friction engagement element 31 that achieves the reverse gear is engaged. At the time of forward running, the friction engagement element 31 that achieves an appropriate gear position is engaged according to the vehicle speed and the engine load (here, the throttle valve opening degree).

The engagement state of the lock-up clutch 20 and each friction engagement element 31 is determined by the hydraulic control through the corresponding hydraulic control valve (control valve) 41. This is done by adjusting the combined pressure. The hydraulic control valve 41 is a solenoid valve provided in the hydraulic control unit 4, and is operated by a command signal of an automatic transmission control unit 5 (hereinafter, referred to as ATCU).

(4) The hydraulic control valve 41 adjusts the engagement state of the lock-up clutch 20 and each friction engagement element 31 by adjusting the oil pressure of the hydraulic oil supplied from an oil pump (not shown) according to the command signal. The present control device is characterized in that the engagement state of the lock-up clutch 20 is adjusted, and in particular, the lock-up clutch 20 is slip-controlled. For this reason, the ATCU 5 includes a shift control unit (shift control means) 50A which is a function for controlling engagement and release of each friction engagement element 31 in order to perform a shift stage such as upshift or downshift. And a lock-up clutch control section (lock-up clutch control means) 50B for controlling the engagement state of the lock-up clutch 20.

Although not shown, the lock-up clutch 20 responds to a differential pressure PA-PR between the torque converter apply pressure PA and the torque converter release pressure PR on both sides (input side and output side), and the release pressure PR is increased. When the pressure is higher than the apply pressure PA, the lock-up clutch 20 is released and does not directly connect the input / output elements of the torque converter. When the release pressure PR becomes lower than the apply pressure PA, the lock-up clutch 20 is engaged and the torque converter is turned on. Reduce or eliminate the slip speed between output elements.

The engagement force of the lock-up clutch 20, that is, the lock-up capacity is determined by the differential pressure PA-PR. The greater the differential pressure, the greater the engagement force of the lock-up clutch 20 and the greater the lock-up capacity. . The differential pressure PA-PR is controlled by the hydraulic control valve 41. The differential pressure PA-PR is simply referred to as lock-up pressure.

[2. Lock-up clutch slip control]
Here, the ATCU 5 will be described focusing on the lock-up clutch control unit 50B. The lock-up clutch control unit 50B includes an engine rotation speed Ne (corresponding to the engine rotation speed) Ne, a turbine rotation speed (corresponding to the turbine rotation speed ωt) Nt of the torque converter 2, a vehicle speed V, a throttle opening TVO, Operating state information of the vehicle, such as a gear ratio ip, an oil temperature (AT fluid temperature) T _ATF , and an engine torque signal (hereinafter, also simply referred to as a torque signal) Te, is input from each sensor.

The lockup clutch control unit 50B calculates a target slip rotation speed Tslp of the lockup clutch 20 (target slip rotation calculation unit) to control the engagement state of the lockup clutch 20 based on these signals. Speed calculation means) 51, an actual slip rotation calculation section (actual slip rotation speed calculation means) 52 for calculating the actual slip rotation speed ωslp, and control so that the actual slip rotation speed ωslp follows the target slip rotation speed Tslp. And a slip control unit (slip control means) 53 that performs the control.

The target slip rotation calculation unit 51 calculates a target slip rotation speed Tslp based on the vehicle operating state such as the vehicle speed V, the throttle opening TVO, the turbine speed Nt, the speed ratio ip, and the oil temperature T _ATF . The target slip rotation speed Tslp is a difference between the input and output rotation speeds of the lock-up clutch 20, and is obtained by subtracting the rotation speed (turbine rotation speed) ωt of the turbine runner 24 from the rotation speed (impeller rotation speed) ωi of the pump impeller 23. Value. Here, a test or the like is performed in advance, and the slip rotation speed at which the occurrence of the torque fluctuation and the muffled sound is minimized is stored in a map or the like in correspondence with the driving state of the vehicle. The target slip rotation speed Tslp is calculated with reference to this map and the like.

The actual slip rotation calculating section 52 calculates an actual slip rotation speed ωslp by subtracting the turbine rotation speed ωt detected by the sensor from the impeller rotation speed ωi detected by the sensor.
Since the impeller rotation speed ωi corresponds to the engine rotation speed Ne, the impeller rotation speed ωi is obtained from the engine rotation speed Ne obtained by the engine rotation sensor 64. The turbine rotation speed ωt is obtained by the turbine rotation sensor 65.

The slip control unit 53 controls the actual slip rotation speed ωslp so as to follow the target slip rotation speed Tslp. Here, the slip rotation speed of the lock-up clutch 20 is determined by the input torque input to the lock-up clutch 20. (Torque difference) ΔT between the output torque output from the lock-up clutch 20 (torque capacity transmitted by the lock-up clutch 20) and the slip control unit 53 adjusts the slip control unit 53 according to the target slip rotation speed. The torque difference ΔT is calculated, and a torque value obtained by subtracting the torque difference ΔT from the input torque to the lock-up clutch 20 is set as a torque capacity target value (hereinafter, also simply referred to as torque capacity) Tlu transmitted by the lock-up clutch 20. Controls the torque capacity of the lock-up clutch 20 to achieve the target slip rotation speed I do.

(4) The slip control unit 53 controls the slip state of the lock-up clutch 20 using feedback control and feedforward control. Therefore, as shown in FIG. 2, the slip control unit 53 includes a slip torque capacity calculation unit (slip torque capacity calculation means) 53A having a feedback control unit 54 and a feedforward control unit 55, a command value conversion unit 58, The slip torque capacity calculator 53A calculates a torque value (slip torque capacity) corresponding to the target slip rotation speed, and derives a command value for controlling the engagement state of the lock-up clutch 20 based on the slip torque capacity. I am trying to do it.

The slip control unit 53 will be further described.
As shown in FIG. 2, the slip control unit 53 performs a process corresponding to a sudden change in torque, specifically, phase lead compensation, on the target slip rotation speed Tslp output from the target slip rotation calculation unit 51. . The target slip rotation speed Tslpa subjected to this processing is sent to the feedback control unit 54 and the feedforward control unit 55 of the slip torque capacity calculation unit 53A.

Further, the output (torque level) Tcnvfb from the feedback control unit 54 and the output (torque level) Tcnvff from the feedforward control unit 55 are sent to the addition unit 53b and added, and the slip for achieving the target slip rotation speed is obtained. It is output as the torque capacity Tcnv.
The slip torque capacity Tcnv calculated by the slip torque capacity calculation section 53A is sent to the subtraction section 53c, and the torque signal processing section 59 as an estimated engine torque calculation section (estimated engine torque calculation means) performs processing based on the engine torque signal Te. The slip torque capacity Tcnv is subtracted from the processed torque value Tea to calculate the torque capacity (control value) Tlu of the lock-up clutch 20. The torque capacity Tlu is sent to the command value conversion unit 58, and the lock-up clutch 20 is converted into an instruction current value Ilu of the control valve 41 for controlling the engagement state of the control valve 20 and output.

The feedback control unit 54 processes the target slip rotation speed Tslpa according to the reference model, performs processing relating to the dead time of the lock-up clutch 20 with respect to the output target slip rotation speed, and calculates the processed target slip rotation speed Tslp. A difference errslp (= Tslp−ωslp) from the actual slip rotation speed ωslp calculated by the actual slip rotation calculation unit 52 is calculated. Further, in order to suppress the difference errslp, a process of proportional / integral control (PI control) is performed to convert the slip rotation amount into a feedback slip torque capacity Tcnvfb, which is a torque amount, and to output the feedback control value.

The feedforward control unit 55 performs a process for compensating the phase with respect to the target slip rotation speed Tslpa, converts the obtained target slip rotation speed Tslpff into a feedforward slip torque capacity Tcnvff, and outputs it as a feedforward control value.

In the slip torque capacity calculation unit 53A, the feedback slip torque capacity Tcnvfb output from the feedback control unit 54 and the feedforward slip torque capacity Tcnvff output from the feedforward control unit 55 are added by the addition unit 53b, It is output as slip torque capacity Tcnv.

Further, the torque signal processing section 59 performs a dead time process (reference numeral 59a), a first-order lag process (reference numeral 59b), and a gain correction (reference numeral 59c) on the engine torque signal Te, and outputs a torque value Tea.
However, the gain used for gain correction in the torque signal processing unit 59 (hereinafter, also simply referred to as gain) is increased under specific conditions. This will be described later.

The subtractor 53c calculates the torque capacity Tlu of the lock-up clutch 20 by subtracting the slip torque capacity Tcnv from the torque value Tea based on the engine torque signal Te.
The command value converter 58 performs a torque-differential pressure conversion process on the torque capacity Tlu, performs phase lead compensation, performs a command pressure-current conversion process, and outputs the obtained indicated current value Ilu to the control valve 41. I do.

As described above, a current is sent to the solenoid of the control valve 41 in accordance with the command current value Ilu output from the slip control unit 53, and the hydraulic pressure (differential pressure) of the lock-up clutch 20 is set to the predetermined value Plu by the control valve 41. The slip state of the lock-up clutch 20 is controlled to the target state.

In the lock-up clutch 20, since the torque capacity is controlled to the value of Tlu during the slip control, the difference Ttc (= Te-Tlu) between the torque value Tea based on the engine torque signal Te and the torque capacity Tlu is determined as the slip torque. Capacity. In addition, the slip rotation (rotation speed ωslp) of the lock-up clutch 20 is changed according to the slip torque amount (= Ttc−Iedωt / dt) from which the inertia torque change amount Iedωt / dt due to the change in the turbine rotation speed ωt is subtracted. , With a predetermined response characteristic [ωslp = Gslp / (Tcslps + 1)].
In this slip control, the capacity of the lock-up clutch 20 is gradually reduced even when the torque of the engine 1 does not increase. Thus, a decrease in the engine speed Ne can be suppressed, and it is possible to prevent the actual slip rotation speed ωslp from decreasing and the lock-up clutch 20 from being engaged.

[3. Gain used for gain correction of torque signal Te]
Since the engine torque signal Te is calculated based on the detection result of the operating state of the engine 1 such as the engine speed Ne, the calculation timing is delayed, and the engine torque signal Te is delayed with respect to the actual engine torque. I know that.

As described in the section of [Problems to be Solved by the Invention], when the accelerator pedal is depressed, the lock-up capacity becomes too small, so that the engine speed is excessively increased. It is intended to prevent or suppress the occurrence of longitudinal acceleration shock in the vehicle due to an excessive lock-up capacity when the pedal is depressed again.

(4) When the cause of the lockup capacity becoming too small or too large was examined, it was found that the cause was that the engine torque signal Te used for controlling the lockup clutch 20 was delayed with respect to the actual engine torque.

For example, as shown in FIG. 3 (a), when the accelerator pedal is depressed during cruising while the lock-up clutch 20 is slightly slipped and the accelerator pedal is released, the throttle opening is adjusted according to the depression. Since TVO rises and fuel recovery is performed from the fuel cut state, the actual engine torque sharply increases at time t1, and the vehicle enters the drive running state. However, since the engine torque signal Te is delayed with respect to the rapid increase in the actual engine torque, the torque capacity Tlu calculated based on the engine torque signal Te also increases with a delay with respect to the rapid increase in the actual engine torque.
As a result, the torque capacity of the lock-up clutch 20 becomes insufficient, and the engine speed Ne also increases rapidly in response to the rapid increase in the actual engine torque, and the engine speed becomes excessive.

On the other hand, in the present device, in a situation where the accelerator pedal is switched from release (off) to depression (on) and the actual engine torque suddenly increases, for example, as shown in FIG. By temporarily increasing the gain used for gain correction when calculating the torque value Tea from the engine torque signal Te, the torque value Tea is calculated by strongly reflecting the latest engine torque signal Te that has started to increase. I have to.

Therefore, under a predetermined condition, that is, under a condition where switching between the accelerator pedal is turned off and on and a sudden increase in the actual engine torque occurs, the ATCU 5 has a gain changing unit (gain changing means) for increasing the gain by a predetermined amount. ) 60 are provided. Switching of the accelerator pedal between off and on can be detected as, for example, switching of the idle switch between on and off.

However, since the actual engine torque is not detected, it is not possible to directly grasp the sudden increase in the actual engine torque. Therefore, the gain changing unit 60 pays attention to the time change rate ΔTe of the engine torque signal Te when the switching between the off state and the on state of the accelerator pedal occurs, and when the time change rate ΔTe becomes equal to or more than the first predetermined value ΔTe1. It is determined that the situation is such that the actual engine torque suddenly increases, and the gain is increased.

FIG. 3B shows a dashed line and a solid line for Gain, where the dashed line is a target value and the solid line is a command value. The command value changes the gain in a ramp shape to prevent a sudden change in the gain, thereby stabilizing the control.
In addition, the predetermined amount for increasing the gain may be a fixed amount by performing a test in advance, or may be a variable amount such as increasing as the accelerator pedal depressing speed (the rate of time change of the accelerator operation amount) increases. Good.

FIG. 3 illustrates a case where the accelerator pedal is changed from the released state to the depressed state, so that the lock-up capacity becomes too small and the engine speed is excessively increased. However, the accelerator pedal is released from the depressed state to the released state. In the case where the lock-up capacity becomes excessive due to the above, the longitudinal acceleration shock occurs in the vehicle, it is also found that the engine torque signal Te used for controlling the lock-up clutch 20 is delayed with respect to the actual engine torque. are doing.

In other words, when the accelerator pedal is changed from the depressed state to the released state, the actual engine torque sharply decreases, and the engine torque signal Te sharply decreases later. In this case, since the decrease in the engine torque signal Te is delayed, the lock-up capacity becomes excessive, and the lock-up clutch 20 is fully engaged or close to this for a short time, causing a longitudinal acceleration shock in the vehicle. It is considered something.

In this case as well, by temporarily increasing the gain and calculating the torque value Tea by strongly reflecting the latest engine torque signal Te that has begun to decrease, it is possible to prevent or suppress the lock-up capacity from becoming excessive. can do.

Since such an increase in the gain is required only in the vicinity of the transient fluctuation of the engine torque, the gain changing unit 60 determines that the rate of change (absolute value) ΔTe of the torque signal Te is larger than the first predetermined value ΔTe1 during the increase in the gain. Is smaller than the second predetermined value ΔTe2, the increase of the gain is stopped.
Alternatively, the gain changing unit 60 may be configured to stop the process of increasing the gain after a predetermined period of time has elapsed since the gain was increased.

However, if the gain is changed during the shift (while the gear is being switched), the shift control may be hindered. Therefore, a gain change prohibition unit (a gain change prohibiting unit) that prohibits the change of the gain during the shift. 61 is provided to regulate a gain change by the gain changing unit 60.

[4. Action and effect)
Since the vehicle shift control device according to one embodiment of the present invention is configured as described above, for example, as shown in the flowchart of FIG. When the gain becomes equal to or greater than the predetermined value ΔTe1, the gain can be changed by the gain changing unit 60 that increases the gain by a predetermined amount. In FIG. 4, F is a flag that is set to 1 during a gain change, and is set to 0 when the gain is not being changed, that is, when the gain is a normal value.

First, it is determined whether or not the flag F is 0. If the flag F is 0, that is, if the gain is a normal value, it is determined whether or not the idle switch has been switched on and off ( In step S20), if the idle switch has been switched between on and off, it is determined whether or not gear shifting is in progress (step S30). Here, if it is determined that the shift is not being performed, it is determined whether the rate of change (absolute value) ΔTe of the engine torque signal Te is equal to or greater than a first predetermined value ΔTe1 (step S50).

Here, if it is determined that the rate of change (absolute value) ΔTe of the engine torque signal Te is equal to or greater than the first predetermined value ΔTe1, the flag F is set to 1 (step S60) to correct the gain of the engine torque signal Te. Is increased (step S70).
On the other hand, when the flag F is 0 and there is no switching of the idle switch between on and off, even if there is this switching, the gear is being shifted, and the rate of change (absolute value) ΔTe of the engine torque signal Te is the If it is smaller than the predetermined value ΔTe1, the gain is not increased and the gain is set to the normal value (step S40).

When the flag F is set to 1 to increase the gain, the process proceeds from step S10 to step S80, where the rate of change (absolute value) ΔTe of the torque signal Te is smaller than the first predetermined value ΔTe1. It is determined whether or not the value is less than the value ΔTe2, and when the rate of change (absolute value) ΔTe of the torque signal Te is less than the second predetermined value ΔTe2, the flag F is reset to 0 (step S90), and the gain is increased. Is stopped, and the gain is set to the normal value (step S40). Note that it may be determined whether or not a predetermined time set in advance has elapsed since the gain was increased, and after the predetermined time has elapsed, the process of increasing the gain may be stopped to set the gain to a normal value. .

As described above, since the gain for correcting the gain of the engine torque signal Te is increased under a specific condition, a problem that occurs due to the delay of the engine torque signal Te with respect to the actual engine torque is eliminated.
That is, when the accelerator pedal is changed from release to depression, the lock-up capacity becomes too small to prevent the engine speed from rising excessively, and when the accelerator pedal is changed from depression to release, It is possible to avoid or suppress occurrence of longitudinal acceleration shock in the vehicle due to excessive lock-up capacity.

Also, since the gain is increased only by switching the accelerator pedal between on and off (switching the idle switch between off and on), the operation amount of the accelerator pedal (depressed amount or depressed amount) is detected. Thus, the gain can be easily and quickly increased as compared with the case where the gain is increased.
In addition, since the change of the gain is restricted during the shift, the possibility that the change of the gain may hinder the shift control is also avoided.

[5. Others]
As described above, the control device for the torque converter according to one embodiment of the present invention has been described, but the present invention is not limited to this embodiment.
For example, in the above embodiment, the gain itself processed in the gain correction unit 59c is changed. However, a gain correction unit different from the gain correction unit 59c is provided in the torque signal processing unit 59, and the correction processing is performed here. Assuming that the normal value of the gain to be used is 1 and the increase value is a value larger than 1 by a predetermined amount, the engine torque signal Te or a value obtained by processing the engine torque signal Te may be multiplied by this gain to calculate the torque value Tea. .

Further, in the above-described embodiment, the gain changing unit 60 causes a sudden increase in the actual engine torque when the time change rate ΔTe becomes greater than or equal to the first predetermined value ΔTe1 due to the switching between the on and off states of the accelerator pedal. Although the gain is determined to be under the condition and the gain is increased, the time is not limited to the switching between the on and off of the accelerator pedal, and the depression and the return of the accelerator pedal are detected, and the time of the engine torque signal Te is detected. Focusing on the rate of change ΔTe, when the time rate of change ΔTe becomes equal to or greater than the first predetermined value ΔTe1, it may be determined that the situation is such that the actual engine torque suddenly increases.

Claims

A control device that is mounted on a vehicle and controls a slip state of a torque converter having a lock-up clutch interposed between an engine and a stepped automatic transmission,
Target slip rotation calculating means for calculating a target slip rotation speed of the lock-up clutch based on a driving state of the vehicle;
A feedforward control amount based on the target slip rotation speed, and a slip torque capacity calculation means for calculating a slip torque capacity of the lockup clutch from a feedback control amount based on the target slip rotation speed and the actual slip rotation speed;
Estimated engine torque calculating means for calculating an estimated engine torque by correcting the engine torque signal with a gain,
An engagement command pressure calculating means for calculating an engagement command pressure of the lock-up clutch from the estimated engine torque and the slip torque capacity,
A slip control device for a torque converter, comprising: gain changing means for increasing the gain by a predetermined amount when a time change rate of the torque signal becomes equal to or more than a first predetermined value by an accelerator operation of the vehicle.
2. The gain changing unit according to claim 1, wherein the gain changing unit stops increasing the gain when the rate of change of the torque signal becomes smaller than a second predetermined value smaller than the first predetermined value during the increase of the gain. 3. Slip control device for torque converter.
2. The torque converter slip control device according to claim 1, wherein the gain changing unit stops the process of increasing the gain when a predetermined time has elapsed after increasing the gain.
The slip control device for a torque converter according to any one of claims 1 to 3, wherein the predetermined amount is a predetermined constant value.
The slip control device for a torque converter according to any one of claims 1 to 3, wherein the predetermined amount is set to a larger value as the time change rate of the accelerator operation amount is larger.
The slip control device for a torque converter according to any one of claims 1 to 5, further comprising a gain change prohibiting unit that prohibits an increase in the gain during shifting of the stepped automatic transmission.