JPH10184897A - Lock up controller of automatic transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To remarkably inhibit the slip at the lock up, by learning and correcting the lock up engagement capacity to be applied, when a condition to release the lock up is detected during the deceleration traveling of a vehicle, and the slip of the lock up clutch is not confirmed. SOLUTION: The difference obtained by subtracting the learned value of lowering of lock up engaging force at deceleration, from the leaned value of lock up engaging force of the present deceleration, is used as the new learned value of engaging force at deceleration, in the case when the driving condition of a vehicle is a deceleration traveling condition, it is judged that a lock up solenoid 8 is in a lock up off control, and the slip rotation by a slip detection means, by the difference between the rotational frequency of an engine Ne and the rotational frequency of a turbine Nt, is not generated, and the control for updating and lowering the learned value of the lock up engaging force at deceleration by a specific correction width, is performed. Further the learning condition of the lock up engaging force at deceleration is judged, and the correction of the learning of the lock up engaging force is forbidden, when the learning condition of the lock up engagement capacity at deceleration, is not satisfied.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lock-up fastening capacity (fastening force) between an input / output element of a torque converter inserted into a transmission system of an automatic transmission when a vehicle is decelerated.
The present invention relates to a lock-up control device for an automatic transmission that controls so as not to generate an engine strike.

[0002]

2. Description of the Related Art Conventionally, such a lockup control device for an automatic transmission is disclosed, for example, in Japanese Patent Laid-Open No. 5-223164. In such a lock-up control device for an automatic transmission, a lock-up control amount is stored based on a lock-up control amount stored corresponding to a point in time that is earlier by a predetermined delay time from when a rise in the engine rotational speed is detected. The lock-up control amount corresponding to the minimum engagement force that does not cause the up clutch to slip is learned.

[0003]

As an effective means for avoiding engine stall due to sudden deceleration at the time of deceleration lockup, there is deceleration lockup engagement capacity reduction control. This is to reduce the lock-up engagement capacity, thereby suppressing the deformation of the lock-up clutch, the torque converter cover, and the like, and improving the lock-up engagement release response.

[0004] However, if the lockup engagement capacity is excessively reduced, slip rotation occurs, and the fuel efficiency effect due to deceleration lockup is reduced. For this reason, in the lockup engagement capacity control at the time of deceleration, the lockup engagement capacity at the time of deceleration is divided into a predetermined range in which the low engagement capacity side is separated by a slip occurrence region and the high engagement capacity side is separated by an engine stall unavoidable region. Have to fit in.

However, the lock-up control command value-engagement capacity characteristic generally varies greatly, and it is difficult to keep the lock-up engagement capacity during deceleration within a predetermined range without any adjustment means.

[0006] Detecting the asymptotic approach to the low engagement capacity side, which is the slip occurrence area, can be easily realized by monitoring the occurrence of slip. However, since the occurrence of engine stall cannot be tolerated even once, it is difficult to detect the asymptotic approach to the high engagement capacity side, which is the area where engine stall cannot be avoided. Therefore, real-time feedback control and learning control on the high engagement capacity side are impossible.

Therefore, the initial value of the lock-up engagement capacity is learned and controlled by detecting the occurrence of slip on the slip occurrence side, but the learning result may gradually approach the high engagement capacity side due to aging or the like. Sex cannot be denied. As a result, in the lock-up engagement learning control for avoiding engine stall, the lock-up engagement capacity during deceleration is gradually reduced, so that the learning is performed in the vicinity of the occurrence of slip where learning is possible, that is, on the low engagement capacity side. . At this time, if the slip occurs frequently,
There are many problems such as deterioration of fuel economy and discomfort.

The lock-up control device for an automatic transmission according to the first and fourth aspects of the present invention is used when the lock-up engagement capacity during deceleration in the lock-up engagement learning control for avoiding engine stall is learned and corrected to a lower engagement capacity side. An object of the present invention is to solve the problem that slip occurs frequently.

In the lockup control device for an automatic transmission according to the second and fifth aspects, it is necessary to prohibit the learning correction of the lockup engagement capacity when the conditions for learning the lockup engagement capacity during deceleration are not satisfied. It is to solve the problem.

The lock-up control device for an automatic transmission according to the third and seventh aspects solves the problem that it is necessary to accurately check the slip of the lock-up clutch.

In the lockup control device for an automatic transmission according to the present invention, when the lockup engagement capacity in the original deceleration traveling state is insufficient, the lockup engagement capacity in the next deceleration traveling state is more appropriately adjusted. This solves the problem that it is necessary to perform learning correction.

[0012]

According to a first aspect of the present invention, there is provided a lock-up control device for an automatic transmission, wherein a torque converter capable of establishing a lock-up state in which an input and an output are directly connected by a lock-up clutch is provided in a transmission system. In the lockup control device for an automatic transmission having a lockup clutch engagement capacity control means capable of arbitrarily setting the engagement capacity of the lockup clutch, a slip detection means for detecting a slip of the lockup clutch, and a motion state of the vehicle. And a lock-up engagement / release determination means for determining whether to lock or release the lock-up according to the motion state of the vehicle, and the motion state of the vehicle is reduced by the motion state detection means. Is detected, and the lock-up fastening / unlocking means releases the lock-up. If it is detected that the lock-up clutch is to be released, and if the slip detection means does not confirm that the lock-up clutch is slipping, the lock-up engagement is performed by a predetermined amount before starting the normal lock-up release control. Performing control to reduce the capacity, as a result of the lock-up engagement capacity reduction control, when the slip detection of the lock-up is detected by the slip detection means, to store the lock-up engagement capacity before the lock-up engagement capacity reduction control, On the other hand, when the slip detection means does not detect the lock-up slip, the lock-up engagement capacity after the lock-up engagement capacity reduction control is stored, and the lock-up engagement capacity in the next deceleration running state is learned and corrected. It is characterized by having such a configuration.

A lock-up control device for an automatic transmission according to a second aspect of the present invention determines a lock-up engagement capacity learning condition at the time of deceleration. A deceleration lock-up engagement capacity learning condition determining means for inhibiting learning correction of the lock-up engagement capacity is provided.

According to a third aspect of the present invention, in the lock-up control device for an automatic transmission, the slip detecting means may be configured such that a slip amount of the lock-up clutch is larger than a predetermined threshold value and a slip amount of the lock-up clutch. Is detected when the time elapsed after the time falls below a predetermined threshold exceeds a predetermined waiting time, the slip of the lock-up clutch is detected.

According to a fourth aspect of the present invention, there is provided a lock-up control device for an automatic transmission, comprising: a transmission system having a torque converter capable of establishing a lock-up state in which input and output are directly connected by a lock-up clutch. In the lock-up control device, a lock-up clutch engagement capacity control means for arbitrarily setting an engagement capacity of the lock-up clutch, a slip detection means for detecting a slip of the lock-up clutch, and a movement state detection means for detecting a movement state of the vehicle And lock-up engagement / release determination means for determining whether to lock-up or release the lock-up according to the motion state of the vehicle. The motion state of the vehicle can be shifted to a deceleration running state by the motion state detection means. Lock-up is detected by the lock-up engagement / release means and detected. If the slip-up state is detected and the slip detection means does not confirm that the lock-up clutch slips after a predetermined time from the end of the deceleration lock-up shift control, the lock-up engagement capacity is increased by a predetermined amount. When the slip of the lockup is detected by the slip detection means as a result of the lockup engagement capacity reduction control, the lockup engagement capacity before the lockup engagement capacity reduction control is stored, and On the other hand, when the slippage of the lockup is not detected by the slip detection means, the lockup engagement capacity after the lockup engagement capacity reduction control is stored, and the lockup engagement capacity in the next deceleration running state is learned and corrected. It is characterized by having comprised in.

According to a fifth aspect of the present invention, there is provided a lock-up control device for an automatic transmission which determines a lock-up engagement capacity learning condition during deceleration. A deceleration lock-up engagement capacity learning condition determining means for inhibiting learning correction of the lock-up engagement capacity is provided.

According to a sixth aspect of the present invention, there is provided a lock-up control device for an automatic transmission, wherein the slip detecting means controls the slip-up of the lock-up clutch before a predetermined time elapses after the end of the deceleration lock-up shift control. If it is confirmed and the deceleration lock-up engagement capacity learning condition determining means determines that the deceleration lock-up engagement capacity learning condition is satisfied, control is performed to increase the lock-up engagement capacity by a predetermined amount, and The lock-up engagement capacity in the deceleration running state is learned and corrected, and the lock-up during deceleration is released by the lock-up engagement / release determination means.

According to a seventh aspect of the present invention, there is provided a lock-up control device for an automatic transmission, wherein the slip amount of the lock-up clutch is larger than a predetermined threshold value and the slip amount of the lock-up clutch falls below a predetermined threshold value. When the elapsed time exceeds a predetermined waiting time, the slip of the lock-up clutch is detected.

[0019]

According to the lockup control device for an automatic transmission according to the first aspect of the present invention, it is detected that the motion state of the vehicle is a deceleration running state and a state in which lockup should be released, In addition, when slippage of the lock-up clutch is not confirmed, control for reducing the lock-up engagement capacity by a predetermined amount is performed before starting normal lock-up release control. When a lock-up slip is detected as a result of the lock-up engagement capacity reduction control, the lock-up engagement capacity before the lock-up engagement capacity reduction control is stored. On the other hand, if the lockup slip is not detected, the lockup engagement capacity after the lockup engagement capacity reduction control is stored. Based on these stored lock-up engagement capacities, the lock-up engagement capacity in the next deceleration running state is learned and corrected.

As described above, when it is detected that the vehicle is in the decelerating traveling state and the state in which the lockup should be released and the slip of the lockup clutch is not confirmed, the lockup engagement capacity is learned. By performing the correction, it is possible to significantly suppress the slip at the time of lock-up in the coasting state caused by reducing the lock-up engagement capacity.

According to the lockup control device for an automatic transmission according to the second aspect of the present invention, the deceleration lockup engagement capacity learning condition is determined, and if the deceleration lockup engagement capacity learning condition is not satisfied. Prohibits the learning correction of the lock-up engagement capacity. As described above, by determining whether to perform the learning correction of the lock-up engagement capacity based on the deceleration-time lock-up engagement capacity learning condition, it is possible to appropriately learn the lock-up engagement capacity during deceleration.

According to the lock-up control device for an automatic transmission according to the third aspect of the present invention, the slip amount of the lock-up clutch is larger than a predetermined threshold value and the slip amount of the lock-up clutch falls below a predetermined threshold value. If the elapsed time exceeds a predetermined waiting time, a slip of the lock-up clutch is detected. By detecting the slip of the lock-up clutch in this manner,
The slip of the lock-up clutch can be accurately confirmed.

According to the lockup control device for an automatic transmission according to the present invention, it is detected that the motion state of the vehicle shifts to the deceleration running state and the lockup state is to be engaged, and On the other hand, if slippage of the lock-up clutch is not confirmed after a lapse of a predetermined time from the end of the deceleration-time lock-up shift control, control is performed to reduce the lock-up engagement capacity by a predetermined amount. When a lock-up slip is detected as a result of the lock-up engagement capacity reduction control, the lock-up engagement capacity before the lock-up engagement capacity reduction control is stored. On the other hand, if the lockup slip is not detected, the lockup engagement capacity after the lockup engagement capacity reduction control is stored. Based on these stored lock-up engagement capacities, the lock-up engagement capacity in the next deceleration running state is learned and corrected.

As described above, it is detected that the motion state of the vehicle shifts to the deceleration running state, and it is detected that the lockup should be engaged, and the lockup is performed after a lapse of a predetermined time from the end of the deceleration lockup shift control. When the clutch slip is not confirmed, the lock-up engagement capacity is learned and corrected to greatly suppress the slip during lock-up in the coasting state caused by reducing the lock-up engagement capacity. it can.

According to the lock-up control device for an automatic transmission according to the fifth aspect of the present invention, the deceleration lock-up engagement capacity learning condition is determined, and if the deceleration lock-up engagement capacity learning condition is not satisfied. Prohibits the learning correction of the lock-up engagement capacity. As described above, by determining whether to perform the learning correction of the lock-up engagement capacity based on the deceleration-time lock-up engagement capacity learning condition, it is possible to appropriately learn the lock-up engagement capacity during deceleration.

According to the lock-up control device for an automatic transmission according to the present invention, slippage of the lock-up clutch is confirmed before a predetermined time elapses after completion of the deceleration lock-up shift control, and When it is determined that the lock-up engagement capacity learning condition is satisfied, the control for increasing the lock-up engagement capacity by a predetermined amount is performed, and the lock-up engagement capacity in the next deceleration running state is learned and corrected, and deceleration is performed. When unlocked.
With this control, when the lock-up engagement capacity in the original deceleration traveling state is insufficient, the lock-up engagement capacity in the next deceleration traveling state can be more appropriately learned and corrected. Can be further greatly suppressed during the lock-up of the coasting state that occurs due to the reduction in the vehicle speed.

According to the lock-up control device for an automatic transmission according to the present invention, the slip amount of the lock-up clutch is larger than a predetermined threshold value and the slip amount of the lock-up clutch is lower than the predetermined threshold value. If the elapsed time exceeds a predetermined waiting time, a slip of the lock-up clutch is detected. By detecting the slip of the lock-up clutch in this manner,
The slip of the lock-up clutch can be accurately confirmed.

[0028]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a lockup control device for an automatic transmission according to the present invention will be described in detail with reference to the drawings. FIG. 1 is a diagram showing an embodiment of a lockup control device for an automatic transmission according to the present invention. In the figure, it is assumed that an automatic transmission 1 receives power of an engine 3 through a torque converter 2, shifts input rotation at a gear ratio according to a selected shift speed, and transmits the power to an output shaft 4.

Here, the automatic transmission 1 is provided with various valves and the like to regulate a line pressure serving as an operating oil pressure, or based on the line pressure, a constant pressure (pilot pressure) to be used for speed change control and lock-up control. ) Is provided. The selected shift speed is determined by a combination of ON and OFF of the shift solenoids 6 and 7 in the control valve 5, and the torque converter 2 also controls the input / output element by controlling the lock-up solenoid 8 in the control valve 5. Lock-up clutch (not shown) between
And the relative rotation (slip amount) between them can be limited.

When the drive duty (D) is 0%, the lock-up solenoid 8 reduces the engagement force (engagement capacity) of the lock-up clutch to zero, and the torque converter 2
Is set to the converter state where the slip amount is maximized, and when the drive duty (D) is 100%, the lock-up clutch is set to the maximum engagement force generating state, and the torque converter 2 is set to the lock-up state where the slip amount is zero. It shall be. The lock-up control valve in the control valve 5 used for these controls is open when the driving duty is 0%, and when the driving duty is 100%.
In the hydraulic control valve (control valve) that switches to the engagement side,
In the intermediate capacity control using the duty value in the range between
The engagement capacity of the lock-up clutch can be arbitrarily set according to the duty ratio. In this case, the lock-up control system of the automatic transmission control system can be configured to include the lock-up solenoid 8, the hydraulic control system of the lock-up control valve and the lock-up clutch, and a part of the following controller.

ON / OFF of shift solenoids 6, 7;
The drive duty D (lock-up clutch engagement pressure command value) of the lock-up solenoid 8 is controlled by a transmission controller 9, and the transmission controller 9 has a throttle opening for detecting the throttle opening TVO of the engine 3. Engine rotation sensor 11 for detecting a signal from degree sensor 10 and engine speed Ne of engine 3
, A signal from a turbine rotation sensor 12 for detecting the input rotation speed (turbine rotation speed) Nt of the automatic transmission 1, and a transmission output rotation sensor 13 for detecting the output rotation speed No of the transmission output shaft 4. And a signal from an oil temperature sensor 14 for detecting the transmission operating oil temperature.

Here, the input information from the transmission output rotation sensor 13 is applied to the shift control and is used as a parameter for determining whether or not the motion state of the vehicle is in a deceleration state or for other conditions. be able to.

The transmission controller 9 executes a speed change control program (not shown) based on the various input information to control the speed change of the automatic transmission 1 via the shift solenoids 6 and 7. By executing the program shown, the lock-up control of the torque converter 2 according to the present invention is performed via the lock-up solenoid 8 as described later.

For the lock-up control, for example, from the throttle opening TVO and the output rotational speed No for each specific shift speed or each shift speed, a lock-up region in which the torque increasing function and the torque fluctuation absorbing function by the torque converter 2 are unnecessary. The control area is determined, for example, during operation in the converter area or during operation in the converter area where these functions are necessary.
The drive control of the lock-up solenoid 8 controls the torque converter 2 to be in a lock-up state in the lock-up region, and to release the torque converter 2 in the converter region to bring the torque converter 3 into the converter state. I do.

For detecting the occurrence of slippage of the lock-up clutch, for example, the difference between the engine speed Ne and the turbine speed Nt, the ratio between the engine speed Ne and the turbine speed Nt, or an amount corresponding thereto is determined. In this case, the transmission controller 9 is configured to control the engine speed Ne input to the transmission controller 9.
It is assumed that the difference between the engine speed and the turbine speed Nt is monitored, and a check is made as to whether or not the difference is close to a value at which the engagement of the L / U can be confirmed.

Further, as an indication of the driving state of the vehicle,
In addition to the vehicle speed V calculated from the output rotational speed No, the throttle opening TVO, the engine rotational speed Ne, the engine intake air amount, the engine intake negative pressure, the auxiliary device driving state, the braking device differential state, or any of them is obtained. One of the change speed, the vehicle running load, and the engine torque is used.

FIG. 2 is a flowchart illustrating a first embodiment of the lockup control device for an automatic transmission according to the present invention. This routine is for learning and correcting the lock-up engagement force when it is determined that the vehicle is in the decelerating running state and the lock-up off control is being performed, and no slip rotation occurs. First, in step S1, it is determined whether or not the lock-up / off control should be performed. When performing the lock-up off control, in step S2, it is determined whether or not the deceleration lock-up engagement force learning flag is ON, that is, whether or not the deceleration lock-up clutch engagement force learning control is to be performed.

The deceleration lockup engagement force learning flag is set to O
If N, in step S3, it is checked whether the deceleration-time lockup engagement force learning condition is satisfied. In the present embodiment, the transmission operating oil temperature obtained from the signal from the oil temperature sensor 14 (FIG. 1), the line pressure thereof, the pilot pressure, and the control power supply voltage are shown as the conditions for learning the lockup engagement force during deceleration. Use one of the following.

If the condition for learning the lock-up engagement force at the time of deceleration is satisfied, in step S4, it is determined whether or not the learning start flag indicating that the learning control has been started is turned on, that is, the predetermined amount of lock. It is determined whether or not the up fastening force has been reduced. If the learning start flag is not ON, that is, if it is OFF, step S5
The deceleration lock-up engagement force learning value is updated as a new deceleration lock-up engagement force learning value obtained by subtracting the deceleration lock-up engagement force reduction learning range from the current deceleration lock-up engagement force learning value. I do. That is, control is performed to reduce the lock-up fastening force only once within a predetermined correction range (a learning range for decreasing the lock-up fastening force during deceleration).

Next, in step S6, a learning waiting time that must elapse before the slip occurrence confirmation control (which will be described later in step S14) (this is
It will be used in a later step S11. ). In this case, the learning waiting time is a predetermined time in consideration of a delay in a change in the hydraulic pressure of the hydraulic system of the automatic transmission 1 (FIG. 1) after the deceleration lock-up engagement force is corrected to the release side by the learning amount. Thereafter, in step S7, a slip occurrence confirmation threshold value used in a subsequent step S14 (more specifically, described in step S61 of FIG. 4) is read. Next, in step S8, a learning waiting time timer (not shown) for measuring the current learning waiting time is initialized. That is, initialization for starting learning control is performed. Then, in step S9, the learning start flag is turned ON.

In step S4, the learning start flag is set to O
N, or after turning on the learning start flag in step S9, that is, in steps S1 to S1.
In S9, it is determined to start the learning control, and after the data processing for that is completed, the deceleration lock-up control for learning is performed in step S10 using the newly updated learning value.

After the deceleration lock-up control for learning is completed, in step S11, the learning waiting time measured by the learning waiting time timer (not shown) is changed to the learning waiting time read in step S6. It is determined whether or not it has elapsed. That is, it is determined whether or not a predetermined time has passed in anticipation of a delay in a change in the hydraulic pressure of the hydraulic system of the automatic transmission 1 (FIG. 1) after the deceleration lock-up engagement force has been corrected toward the release side by the amount of learning.

If the learning waiting time measured by the learning waiting time timer (not shown) does not exceed the learning waiting time read in step S6, in step S12, the learning waiting time timer (not shown) is used. ) Is incremented. On the other hand, when the learning waiting time has elapsed, in step S13, it is determined that the vehicle is in a state of waiting for the occurrence of slip in step S14 (more specifically, in steps S63 and S65 in FIG. 4). It is determined whether or not the indicated slip occurrence confirmation waiting flag is ON.

After completion of step S12 or step S13
When it is determined that the slip occurrence confirmation waiting flag is ON in step S14, slip occurrence confirmation control is performed in step S14, and then, in step S15, a slip occurrence confirmation flag indicating that slip rotation has occurred in step S14. (Details will be described in step S67 of FIG. 4). That is, in step S15, it is determined whether or not slip rotation has occurred as a result of the update of the deceleration lock-up engagement force learning value in S5, that is, the learning of the deceleration lock-up engagement force reduction. This step S14
Will be described later in detail using the routine of FIG.

The slip occurrence confirmation flag is OFF,
That is, if the occurrence of slip rotation is not confirmed, the present logic is terminated. On the other hand, if the slip occurrence confirmation flag is ON, it is considered that the slip rotation has occurred because the learning value of the lockup engagement force at the time of deceleration has been updated in step S5, and in the next step S16,
The sum of the deceleration lock-up engagement force learning value updated in step S5 and the deceleration lock-up engagement force reduction learning width (that is, the deceleration lock-up engagement force learning value before update) is used for the next deceleration lock-up. By using the engagement force learning value, the result of the current deceleration lock-up engagement force decrease learning (that is, the deceleration lock-up engagement force learning value updated in step S5) is rejected.

If it is determined in step S13 that the slip occurrence confirmation waiting flag is OFF, that is, if it is determined that the vehicle is not in the wait state for slip occurrence confirmation, it is determined that no slip rotation has occurred, and the learning of the lockup engagement force during deceleration is performed. The result (that is, the deceleration lock-up engagement force learning value updated in step S5) is used for the next deceleration lock-up control as the next deceleration lock-up engagement force learning value.

If it is determined in step S13 that the slip occurrence confirmation waiting flag is OFF, or after the process in step S16, the process enters the main learning control termination process in steps S17 to S20. In this case, first, in step S17, the deceleration lockup engagement force learning flag is turned off.
Then, in step S18, the slip occurrence confirmation waiting flag is turned off, and then, in step S19.
In step S20, the slip occurrence confirmation flag is turned off. Then, in step S20, the learning start flag is turned off.
And then terminate this logic.

When the deceleration lock-up engagement force learning flag is OFF in step S2, or in step S3
When the deceleration lock-up engagement force learning condition is not satisfied in this case (in this case, when the deceleration lock-up engagement force learning flag is ON, that is, the motion state of the vehicle is in the deceleration state, and the lock-up off control is performed. In this case, it is determined that the main learning control is not performed, and step S21 is performed.
To turn off the lockup engagement force learning flag during deceleration,
Thereafter, in step S22, the learning start flag is set to O
It is determined whether or not N.

If the learning start flag is ON, in step S23, as in step S16, the sum of the deceleration lock-up engagement force learning value updated in step S5 and the deceleration lock-up engagement force reduction learning width in step S5 is added. , The next deceleration lock-up engagement force learning value,
The result of the current deceleration-time lock-up fastening force reduction learning is rejected, and then, in step S24, the learning start flag is turned off, and the learning control is interrupted.

If it is determined in step S22 that the learning start flag is OFF, steps S23 and S2
Skip 4 After it is determined in step S22 that the learning start flag is OFF or after the processing in step S24, in step S25, lock-up / off control is performed, and then the present logic ends.

If it is determined in step S1 that the lock-up off control is not to be performed, it is determined in step S26 whether or not to perform the deceleration lock-up control. If it is determined that the deceleration lockup control is to be performed, the deceleration lockup engagement force learning flag is turned on in step S27, the slip occurrence confirmation flag is turned off in step S28, and the operation is switched to the lockup off control. Prepare. Next, step S29
In, the lock-up control during deceleration is performed, and then the present logic is terminated.

If it is determined in step S26 that the lockup control during deceleration is not to be performed, another lockup control is performed in step S30.

According to the present embodiment, when it is determined that the vehicle is in the deceleration running state and the lock-up off control is being performed and the slip rotation does not occur, the current deceleration lock-up engagement force learning value is used. Since the difference obtained by subtracting the learning range for decreasing the lock-up fastening force during deceleration is used as a new learning value for the lock-up fastening force during deceleration, the lock-up fastening force is updated by updating the learning value for the lock-up fastening force during deceleration. The slip at the time of lock-up of the coasting state which occurs in the above can be largely suppressed.

Further, the learning condition of the lock-up engagement force at the time of deceleration is determined. If the learning condition of the lock-up engagement capacity at the time of deceleration is not satisfied, the learning correction of the lock-up engagement force is prohibited. The learning of the lock-up fastening force can be performed.

FIG. 3 is a flowchart illustrating a lock-up control device for an automatic transmission according to a second embodiment of the present invention. This routine is for learning and correcting the lock-up engagement force when it is determined that the vehicle is in the deceleration running state and the lock-up control is being performed, and the slip rotation does not occur. This is also
When the occurrence of slip rotation is confirmed before a predetermined time elapses after the end of the deceleration lock-up shift control and the deceleration lock-up engagement force learning condition is determined to be satisfied, the lock-up engagement is performed by a predetermined amount. The control for increasing the force is performed, the lock-up engagement capacity in the next deceleration running state is learned and corrected, and the lock-up during deceleration is performed.

First, in step S31, it is determined whether or not the current deceleration lock-up control should be performed. If it is determined that the lockup control during deceleration should be performed, it is checked in step S32 whether or not this routine is the first time since the start of the lockup control during deceleration. 1
If it is the first time, in step S33, a learning waiting time (this will be used in later step S35) to elapse before the slip occurrence confirmation control (described later in step S46) is performed is read. Also in this case, the learning waiting time is set to a predetermined time in consideration of a delay in a change in hydraulic pressure of the hydraulic system of the automatic transmission 1 (FIG. 1) after the deceleration lock-up engaging force is corrected to the release side by the learning amount. Thereafter, in step S34, a learning waiting time timer (not shown) for measuring the current learning waiting time is initialized, and initialization for starting learning control is performed.

If it is determined in step S32 that it is not the first time, that is, it is the second time or more after the start of the lockup control during deceleration, steps S3 and S4
To skip. Therefore, the reading of the learning waiting time and the initialization of the learning waiting time timer (not shown) are not performed.

If it is determined in step S32 that it is not the first time, or after the learning wait time timer (not shown) is initialized in step S34, the learning wait time timer (not shown) is measured in step S35. It is determined whether the learning waiting time has passed the learning waiting time read in step S33. That is, it is determined whether or not a predetermined time has passed in anticipation of a delay in a change in the hydraulic pressure of the hydraulic system of the automatic transmission 1 (FIG. 1) after the deceleration lock-up engagement force has been corrected toward the release side by the amount of learning.

If the learning waiting time measured by the learning waiting time timer (not shown) has not passed the learning waiting time read in step S33, in step S36, the learning waiting time timer (not shown) is used. ) Is incremented and the time elapses. On the other hand, if the learning waiting time has elapsed, it is checked in step S37 whether the deceleration lockup engagement force learning condition is satisfied. Also in the present embodiment, the transmission operating oil temperature obtained from a signal from the oil temperature sensor 14 (FIG. 1), its line pressure, pilot pressure, and control power supply voltage are shown as the conditions for learning the lockup engagement force during deceleration. Use one of the following.

If the condition for learning the lock-up engagement force at the time of deceleration is not satisfied, at step S38, the lock-up engagement force learning flag at the time of deceleration indicating whether to learn the engagement force of the lock-up clutch at the time of deceleration is turned off. And then
Cancel the subsequent learning control. On the other hand, when the deceleration-time lock-up engagement force learning condition is satisfied, in step S39, it is determined whether the learning start flag indicating that the learning control has been started is turned ON, that is, the locking is performed by a predetermined amount. It is determined whether or not the up fastening force has been reduced. If the learning start flag is not ON, that is, if it is OFF, in step S40, the difference obtained by subtracting the learning range for decreasing the lockup engagement force during deceleration from the current learning value of the lockup engagement force during deceleration is used as the new deceleration lock. The deceleration-time lockup engagement force learning value is updated as the up engagement force learning value. That is, control is performed to reduce the lock-up fastening force only once within a predetermined correction range (a learning range for decreasing the lock-up fastening force during deceleration).

Next, in step S41, a slip occurrence confirmation threshold value used in a later step S46 (which will be described in more detail in step S61 of FIG. 4) is read, and in step S42, a deceleration lock-up engagement force learning flag is determined. Is turned on, and in step 43, the learning start flag is turned on, and initialization for starting learning control and setting of the flag are performed. If it is determined in step S39 that the learning start flag is OFF, the processes in steps S40 to S43 are not performed.

After the initialization of steps S31 to S43 is completed, that is, after the learning waiting time timer (not shown) is incremented in step S36, and after the deceleration lock-up engagement force flag is turned off in step S38. In step S39, the learning start flag
After the FF is determined or the learning start flag is turned on in step S43, the deceleration lock-up control is performed in step S44.

Thereafter, in step S45, it is confirmed whether or not the deceleration lock-up engagement force learning flag is ON, and it is determined whether or not to execute the deceleration lock-up engagement force learning. If the deceleration lock-up engagement force flag is OFF, the learning control end process of steps S51 to S53 described later is not performed, and the deceleration lock-up control is continued next time. On the other hand, if it is determined to be ON, that is, to execute the lockup learning during deceleration, in step S46, slip occurrence confirmation control is performed to determine whether or not slip rotation is currently occurring. I do. Step S46 will be described later in detail with reference to the routine of FIG.

Thereafter, in step S47, it is determined whether or not a slip occurrence confirmation flag (which will be described in detail in step S67 in FIG. 4) indicating that slip rotation has occurred in step S46 is ON. Even when the slip occurrence confirmation flag is OFF, the learning control termination process of steps S51 to S53 described later is not performed, and the deceleration lockup control is continued next time.

On the other hand, the slip occurrence confirmation flag is set to O
If it is N, it is determined that slip rotation is currently occurring, and in step S48, it is determined whether the learning start flag is ON.

If the learning start flag is ON, in step S49, it is considered that slip rotation has occurred because the learning value of the lockup engagement force at deceleration has been updated in S40, and the updated lockup during deceleration is updated in step S40. The sum of the force learning value and the deceleration lock-up engagement force reduction learning width (that is, the deceleration lock-up engagement force learning value before updating) is used as the next deceleration lock-up engagement force learning value, The result of the deceleration-time lock-up engagement force reduction learning (that is, the deceleration-time lock-up engagement force learning value updated in step S40) is rejected.

On the other hand, when the learning start flag is OFF, it is determined in step S50 that the original deceleration lock-up engagement force learning value is insufficient, and the deceleration lock-up engagement force learning value is reduced to the original deceleration lock-up engagement force learning value. The deceleration lock-up engagement force increase learning is performed by taking the sum of the time-dependent lock-up engagement force increase learning width as the next deceleration-time lock-up engagement force learning value.

After rejecting the learning result of the decrease in the lock-up fastening force during deceleration in step S49 or after step S50
After performing the deceleration-time lock-up engagement force increase learning at, the control enters the main learning control termination processing of steps S51 to S53. In this case, first, in step S51, the slip occurrence confirmation flag is turned off, and then in step S52
In step S53, the learning start flag is turned off. Then, in step S53, the lockup control during deceleration is switched to the lockup off control during deceleration to prevent slip rotation from occurring during lockup control during deceleration. finish.

If it is determined in step S31 that the lockup control during deceleration is not to be performed, other lockup control is performed in step S54, and then the slip occurrence confirmation flag is turned off in step S55, and the learning control during deceleration for the next time is performed. Prepare for.

According to this logic, it is determined that the motion state of the vehicle is the deceleration running state and the lock-up control is performed, and no slip rotation occurs after a predetermined time has elapsed from the end of the deceleration lock-up shift control. In this case, the difference between the current deceleration lock-up engagement force learning value and the deceleration lock-up engagement force decrease learning width is used as a new deceleration lock-up engagement force learning value to update the deceleration lock-up engagement force learning value. By doing so, it is possible to significantly suppress the slip at the time of lock-up in the coasting state caused by reducing the lock-up fastening force.

Further, a condition for learning the lock-up engagement force at the time of deceleration is determined, and if the condition for learning the lock-up engagement capacity at the time of deceleration is not satisfied, the learning correction of the lock-up engagement force is prohibited, so that a suitable deceleration at the time of deceleration is achieved. Lock-up fastening force learning can be performed.

Further, if occurrence of slip rotation is confirmed before a predetermined time elapses after the end of the deceleration lock-up shift control and if it is determined that the deceleration lock-up engagement capacity learning condition is satisfied, the original The sum of the deceleration lock-up engagement force learning value and the deceleration lock-up engagement force increase learning width is used as the next deceleration lock-up engagement force learning value, and by switching to the deceleration lock-up off control, The lockup engagement capacity in the deceleration traveling state of the vehicle can be more appropriately learned and corrected, and thereby the slip at the time of lockup in the coasting state caused by reducing the lockup engagement force can be further suppressed. be able to.

FIG. 4 is a flowchart for explaining the slip occurrence confirmation control in the flowcharts of FIGS. 2 and 3.
This logic is executed in step S14 of FIG. 2 and step S46 of FIG. 3, and has elapsed since the slip rotation speed was larger than the slip occurrence confirmation threshold value and the slip rotation speed fell below the slip occurrence confirmation threshold value. The slip rotation is detected when the time exceeds the slip occurrence confirmation waiting time.

First, in step S61, it is determined whether or not the current slip rotation speed is greater than a slip occurrence confirmation threshold value, which is a measure of slip rotation, and it is checked whether slip rotation has occurred. If the current slip rotation number is larger than the slip occurrence confirmation threshold value, it is determined that slip rotation has occurred, and in step S62, a slip occurrence confirmation waiting time for waiting for confirmation of slip occurrence is read. In step S13, the slip occurrence confirmation waiting flag used in step S13 of FIG.
N is set, and control is shifted to a slip occurrence confirmation waiting state.

If the current slip rotation number is smaller than the slip occurrence confirmation threshold value in step S61, it is determined that slip rotation has not occurred, and in step S64, a slip occurrence confirmation wait timer (not shown) is initialized. Thereafter, in step S65, the slip occurrence confirmation waiting flag is turned off to prepare for the occurrence of slip rotation.

After turning on the slip occurrence confirmation waiting flag in step S63, the time measured by the slip occurrence confirmation waiting time timer (not shown) is compared with the slip occurrence waiting time, and the duration of the slip rotation occurrence is determined. Confirm. When it is determined that the time measured by the slip occurrence confirmation waiting time timer (not shown) is longer than the slip occurrence confirmation waiting time and that the occurrence of slip rotation has been sufficiently continued, the slip occurrence confirmation flag is turned on in step S67. And occurrence of slip rotation is confirmed.

If it is determined in step S66 that the time measured by the slip occurrence confirmation waiting time timer (not shown) is shorter than the slip occurrence confirmation waiting time, and it is determined that the slip rotation has not been sufficiently generated, step S68. In, a slip generation confirmation waiting time timer (not shown) is incremented to measure the duration. Upon completion of the above control, the process returns to the main routine of FIG.

According to this routine, when the slip rotation speed is greater than the slip occurrence confirmation threshold value and the time measured by the slip occurrence confirmation wait time timer (not shown) exceeds the slip occurrence confirmation wait time, the slip rotation The occurrence of slip rotation can be accurately confirmed by confirming the occurrence of slip rotation.

[Brief description of the drawings]

FIG. 1 is a diagram showing an embodiment of a lockup control device for an automatic transmission according to the present invention.

FIG. 2 is a flowchart illustrating a lock-up control device for an automatic transmission according to a first embodiment of the present invention.

FIG. 3 is a flowchart illustrating a lock-up control device for an automatic transmission according to a second embodiment of the present invention.

FIG. 4 is a flowchart illustrating a slip occurrence confirmation control in the flowcharts of FIGS. 2 and 3;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Automatic transmission 2 Torque converter (T / C) 3 Engine 4 Output shaft 5 Control valve 6,7 Shift solenoid 8 Lock-up solenoid 9 Transmission controller 10 Throttle opening sensor 11 Engine rotation sensor 12 Turbine rotation sensor 13 Transmission output Rotation sensor 14 Oil temperature sensor D Duty solenoid Ne Engine rotation speed No Output shaft rotation speed Nt Turbine rotation speed TVO Throttle opening

Claims (7)

[Claims] 1. A lock-up control device for an automatic transmission having a torque converter in a transmission system capable of establishing a lock-up state in which an input and an output are directly connected by a lock-up clutch, wherein an engagement capacity of the lock-up clutch is arbitrarily set. Lock-up clutch engagement capacity control means, a slip detection means for detecting slip of the lock-up clutch, a movement state detection means for detecting a movement state of the vehicle, and engagement or release of lock-up according to the movement state of the vehicle. Lock-up engagement / release determination means for determining, wherein the movement state detection means detects that the vehicle is in a deceleration running state and the lock-up engagement / release means should release lock-up. State is detected, and by the slip detecting means, If the slip of the lock-up clutch is not confirmed, a control for reducing the lock-up engagement capacity by a predetermined amount is performed before starting the normal lock-up release control, and as a result of the lock-up engagement capacity reduction control, When the slip of the lock-up is detected by the slip detection means, the lock-up engagement capacity before the lock-up engagement capacity reduction control is stored.
When the slip of the lock-up is not detected by the slip detecting means, the lock-up engagement capacity after the lock-up engagement capacity reduction control is stored, and the lock-up engagement capacity in the next deceleration driving state is learned and corrected. A lock-up control device for an automatic transmission. 2. A deceleration lock-up engagement capacity learning condition is determined. If the deceleration lock-up engagement capacity learning condition is not satisfied, the deceleration lock-up engagement capacity prohibits the learning correction of the lock-up engagement capacity. The lock-up control device for an automatic transmission according to claim 1, further comprising a learning condition determining unit. 3. The system according to claim 2, wherein the slip detecting means is configured to determine whether a time that has elapsed since the slip amount of the lock-up clutch is greater than a predetermined threshold value and the slip amount of the lock-up clutch falls below a predetermined threshold value is a predetermined waiting time. The lock-up control device for an automatic transmission according to claim 1 or 2, wherein the slip of the lock-up clutch is detected when the value exceeds the limit. 4. A lock-up control device for an automatic transmission having, in a transmission system, a torque converter capable of establishing a lock-up state in which an input and an output are directly connected by a lock-up clutch, wherein an engagement capacity of the lock-up clutch is arbitrarily set. Lock-up clutch engagement capacity control means, a slip detection means for detecting slip of the lock-up clutch, a movement state detection means for detecting a movement state of the vehicle, and engagement or release of lock-up according to the movement state of the vehicle. Lock-up engagement / release determination means for determining, wherein the movement state detection means detects that the movement state of the vehicle shifts to the deceleration traveling state, and lock-up is engaged by the lock-up engagement / release means. And the slip detecting means. If the slip of the lock-up clutch is not confirmed after a lapse of a predetermined time from the end of the deceleration-time lock-up shift control, control is performed to reduce the lock-up engagement capacity by a predetermined amount. As a result, when a lock-up slip is detected by the slip detection means, the lock-up engagement capacity before the lock-up engagement capacity reduction control is stored, whereas the lock-up slip is not detected by the slip detection means. The lock-up control of the automatic transmission is characterized in that the lock-up engagement capacity after the lock-up engagement capacity reduction control is stored and the lock-up engagement capacity in the next deceleration driving state is learned and corrected. apparatus. 5. A deceleration lock-up engagement capacity learning condition is determined. If the deceleration lock-up engagement capacity learning condition is not satisfied, the deceleration lock-up engagement capacity learning correction is prohibited. The lock-up control device for an automatic transmission according to claim 4, further comprising learning condition determination means. 6. The slip detection means confirms that the lock-up clutch has slipped before a predetermined time has elapsed from the end of the deceleration lock-up shift control, and the deceleration lock-up engagement capacity learning condition determining means determines the slip. When it is determined that the deceleration lock-up engagement capacity learning condition is satisfied, control is performed to increase the lock-up engagement capacity by a predetermined amount, and the lock-up engagement capacity in the next deceleration running state is learned and corrected, 6. A lock-up control device for an automatic transmission according to claim 5, wherein said lock-up engagement / release determination means releases lock-up during deceleration. 7. When the slip amount of the lock-up clutch is larger than a predetermined threshold and the time elapsed since the slip amount of the lock-up clutch falls below a predetermined threshold exceeds a predetermined waiting time, The lock-up control device for an automatic transmission according to any one of claims 4 to 6, wherein slippage of a lock-up clutch is detected.