JP3454061B2 - Lockup control device for automatic transmission - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lockup engagement capacity (engagement force) between torque converter input / output elements inserted in a transmission system of an automatic transmission during vehicle deceleration.
The present invention relates to a lock-up control device for an automatic transmission, which controls so that engine strel is not generated.

[0002]

2. Description of the Related Art Conventionally, such a lockup control device for an automatic transmission is disclosed in, for example, Japanese Patent Laid-Open No. 5-223164. In such a lockup control device for an automatic transmission, the lockup control amount is stored based on the lockup control amount stored at a time point that is a predetermined delay time after the engine speed increase is detected. The lockup control amount corresponding to the minimum engagement force that prevents the up clutch from slipping is learned.

[0003]

As an effective means for avoiding engine stall due to sudden deceleration during deceleration lockup, there is lockup engagement capacity reduction control during deceleration. This reduces the lock-up engagement capacity to suppress deformation of the lock-up clutch, the torque converter cover, etc., and improves the lock-up engagement release response.

However, if the lock-up engagement capacity is reduced too much, slip rotation occurs and the fuel consumption effect due to deceleration lock-up is reduced. Therefore, in lockup engagement capacity control during deceleration, the lockup engagement capacity during deceleration is divided into a predetermined range by dividing the low engagement capacity side by the slip occurrence area and the high engagement capacity side by the engine stall avoidable area. Must fit in.

However, the lock-up control command value-engagement capacity characteristic generally has large individual variation, and it is difficult to keep the lock-up engagement capacity during deceleration within a predetermined range without any adjusting means.

Detecting the asymptotic approach to the low engagement capacity side, which is the slip occurrence region, can be easily realized by monitoring the occurrence of slip. However, since the occurrence of engine stall cannot be permitted even once, it is difficult to detect the asymptotic approach to the high engagement capacity side, which is the engine stall avoidable region. Therefore, real-time feedback control and learning control on the high engagement capacity side are not possible.

Therefore, although the initial value of the lock-up engagement capacity is learned and controlled by detecting the occurrence of slip on the slip occurrence side, the learning result may gradually approach the high engagement capacity side due to changes over time. 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 learning is performed near the occurrence of slip where learning becomes possible, that is, on the low engagement capacity side. . At this time, if it seems that slips occur frequently,
There are many problems such as deterioration of fuel efficiency and discomfort.

The lockup control device for an automatic transmission according to the first and the fourth aspects, when the lockup engagement capacity during deceleration in the lockup engagement learning control for avoiding the engine stall is learned and corrected to the low engagement capacity side. It solves the problem that slips occur frequently.

The lockup control device for an automatic transmission according to claims 2 and 5 must prohibit learning correction of the lockup engagement capacity when the lockup engagement capacity learning condition during deceleration is not satisfied. It solves the problem.

The lock-up control device for the 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.

According to another aspect of the present invention, in the lock-up control device for an automatic transmission, when the lock-up engagement capacity in the original decelerated traveling state is insufficient, the lock-up engagement capacity in the next decelerated traveling state is more appropriate. It solves the problem of needing learning correction.

[0012]

According to a first aspect of the present invention, there is provided a lockup control device for an automatic transmission according to the present invention. In the lock-up control device for an automatic transmission, the lock-up clutch engagement capacity control means that can arbitrarily set the engagement capacity of the lock-up clutch, the slip detection means that detects slip of the lock-up clutch, and the motion state of the vehicle The vehicle includes a motion state detecting unit for detecting and a lockup engagement / release determining unit for determining lockup engagement or release according to the motion state of the vehicle, and the motion state detecting unit determines the motion state of the vehicle in a decelerating traveling state. Is detected and the lockup is performed by the lockup fastening / releasing means. When it is detected that the lockup clutch is in the state to be released, and the slip detection means does not confirm the slip of the lockup clutch, the lockup engagement is performed by a predetermined amount before the normal lockup release control is started. Performing a control to reduce the capacity, as a result of the lockup engagement capacity reduction control, when the slip of the lockup is detected by the slip detection means, the lockup engagement capacity before the lockup engagement capacity reduction control is stored, On the other hand, when the slip-up slip is not detected by the slip detection means, the lock-up engagement capacity after the lock-up engagement capacity lowering control is stored, and the lock-up engagement capacity in the next decelerated traveling state is learned and corrected. It is characterized by being configured as described above.

A lockup control device for an automatic transmission according to a second aspect of the present invention determines a lockup engagement capacity learning condition during deceleration, and if the lockup engagement capacity learning condition during deceleration is not satisfied, the above is established. It is characterized in that a deceleration lockup engagement capacity learning condition determining means for prohibiting learning correction of the lockup engagement capacity is provided.

According to a third aspect of the present invention, in the lock-up control device for an automatic transmission according to the present invention, the slip detection means is such that 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 large. Is detected below the predetermined threshold value, the slip of the lock-up clutch is detected when the time that has elapsed exceeds a predetermined waiting time.

A lockup control device for an automatic transmission according to a fourth aspect of the present invention is an automatic transmission having a torque converter in a transmission system capable of establishing a lockup state in which input and output are directly connected by a lockup clutch. In a lockup control device, a lockup clutch engagement capacity control means capable of arbitrarily setting an engagement capacity of a lockup clutch, a slip detection means for detecting slip of the lockup clutch, and a motion state detection means for detecting a motion state of a vehicle. And lockup engagement / release determination means for determining lockup engagement or release depending on the vehicle motion state, and the vehicle motion state may shift to the deceleration traveling state by the motion state detection means. It is detected and the lockup is fastened by the lockup fastening / releasing means. When it is detected that the lockup clutch is in the proper state and the slip detection means does not confirm the slip of the lockup clutch after a predetermined time has elapsed from the end of the lockup transition control during deceleration, the lockup engagement capacity is a predetermined amount. When a 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 slip-up slip is not detected by the slip detection means, the lock-up engagement capacity after the lock-up engagement capacity lowering control is stored, and the lock-up engagement capacity in the next decelerated traveling state is learned and corrected. It is characterized by being configured in.

A lockup control device for an automatic transmission according to a fifth aspect of the present invention determines a lockup engagement capacity learning condition during deceleration, and if the lockup engagement capacity learning condition during deceleration is not satisfied, the above-mentioned condition is satisfied. It is characterized in that a deceleration lockup engagement capacity learning condition determining means for prohibiting learning correction of the lockup engagement capacity is provided.

According to a sixth aspect of the present invention, in the lock-up control device for an automatic transmission according to the sixth aspect, the slip detection means causes the slip-up of the lock-up clutch to occur before a lapse of a predetermined time after the completion of the lock-up transition control during deceleration. If it is confirmed and the deceleration lock-up engagement capacity learning condition determination 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. The lock-up engagement capacity in the decelerated traveling state is learned and corrected, and the lock-up engagement / release determination means releases the lock-up during deceleration.

In a lockup control device for an automatic transmission according to a seventh aspect of the present invention, the slip amount of the lockup clutch is larger than a predetermined threshold value, and the slip amount of the lockup clutch is less than a predetermined threshold value. The slip of the lock-up clutch is detected when the elapsed time exceeds a predetermined waiting time.

[0019]

According to the lock-up control device for an automatic transmission of the first aspect of the present invention, it is detected that the motion state of the vehicle is the decelerating traveling state and the lock-up state is to be released. In addition, when the slip of the lockup clutch is not confirmed, control is performed to reduce the lockup engagement capacity by a predetermined amount before starting the normal lockup release control. As a result of the lock-up engagement capacity reduction control, when a lock-up slip is detected, the lock-up engagement capacity before the lock-up engagement capacity reduction control is stored. On the other hand, when the lockup slip is not detected, the lockup engagement capacity after the lockup engagement capacity reduction control is stored. Based on the stored lock-up engagement capacity, the lock-up engagement capacity in the next decelerated traveling state is learned and corrected.

In this way, when it is detected that the vehicle is in the deceleration running state and the lockup is to be released, and the slip of the lockup clutch is not confirmed, the lockup engagement capacity is learned. By the correction, it is possible to significantly suppress the slip at the time of lockup in the coasting state that occurs due to the reduction of the lockup engagement capacity.

According to the lock-up control device for an automatic transmission according to the second aspect of the present invention, the lock-up engagement capacity learning condition for deceleration is determined, and when the lock-up engagement capacity learning condition for deceleration is not satisfied. Prohibits learning correction of lock-up engagement capacity. In this way, by determining whether or not to perform the learning correction of the lockup engagement capacity based on the deceleration lockup engagement capacity learning condition, it is possible to perform the suitable deceleration lockup engagement capacity learning.

According to the lock-up control device for an automatic transmission according to a 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 is less than the predetermined threshold value. When the elapsed time exceeds the predetermined waiting time, the slip of the lockup clutch is detected. By detecting the slip of the lockup clutch in this way,
The slip of the lockup clutch can be confirmed accurately.

According to the lock-up control device for an automatic transmission according to claim 4 of the present invention, it is detected that the motion state of the vehicle shifts to the decelerating traveling state and the lock-up state is to be engaged, and When slippage of the lockup clutch is not confirmed after a predetermined time has elapsed from the end of the lockup transition control during deceleration, control is performed to reduce the lockup engagement capacity by a predetermined amount. When a lockup slip is detected as a result of the lockup engagement capacity reduction control, the lockup engagement capacity before the lockup engagement capacity reduction control is stored. On the other hand, when the lockup slip is not detected, the lockup engagement capacity after the lockup engagement capacity reduction control is stored. Based on the stored lock-up engagement capacity, the lock-up engagement capacity in the next decelerated traveling state is learned and corrected.

In this way, it is detected that the motion state of the vehicle shifts to the decelerating traveling state and that the lockup is to be engaged, and the lockup occurs after a predetermined time has elapsed after the end of the deceleration lockup shift control. If the slip of the clutch is not confirmed, by learning and correcting the lock-up engagement capacity, it is possible to significantly suppress the slip at the lock-up in the coasting state caused by the reduction of the lock-up engagement capacity. it can.

According to the lock-up control device for an automatic transmission of the fifth aspect of the present invention, the lock-up engagement capacity learning condition during deceleration is determined, and when the lock-up engagement capacity learning condition during deceleration is not satisfied. Prohibits learning correction of lock-up engagement capacity. In this way, by determining whether or not to perform the learning correction of the lockup engagement capacity based on the deceleration lockup engagement capacity learning condition, it is possible to perform the suitable deceleration lockup engagement capacity learning.

According to the lock-up control device for an automatic transmission according to claim 6 of the present invention, the slip-up of the lock-up clutch is confirmed before the elapse of a predetermined time after the completion of the lock-up transition control during deceleration, and the deceleration is performed. When it is determined that the 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, and the deceleration is performed. When unlocked.
By this control, when the lockup engagement capacity in the original deceleration running state is insufficient, the lockup engagement capacity in the next deceleration running state can be learned and corrected more appropriately, and as a result, the lockup engagement capacity can be corrected. It is possible to further greatly suppress the slip at the time of lockup in the inertia running state caused by the decrease of

According to the lockup control device for an automatic transmission according to claim 7 of the present invention, the slip amount of the lockup clutch is larger than a predetermined threshold value, and the slip amount of the lockup clutch is less than the predetermined threshold value. When the elapsed time exceeds the predetermined waiting time, the slip of the lockup clutch is detected. By detecting the slip of the lockup clutch in this way,
The slip of the lockup clutch can be confirmed accurately.

[0028]

BEST MODE FOR CARRYING OUT THE INVENTION 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 the automatic transmission 1 receives the power of the engine 3 via the torque converter 2, shifts the input rotation at a gear ratio according to the selected gear, and transmits the power to the output shaft 4.

Here, the automatic transmission 1 is equipped with various valves and regulates a line pressure which is an operating hydraulic pressure, or a constant pressure (pilot pressure) used for gear shift control or lockup control based on the line pressure. ) Is included in the control valve 5. The selected shift speed is determined by the combination of ON and OFF of the shift solenoids 6 and 7 in the control valve 5, and the torque converter 2 is also input / output element by the duty control of the lockup solenoid 8 in the control valve 5. Lockup clutch between (not shown)
And the relative rotation (slip amount) between them can be limited.

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

ON / OFF of the shift solenoids 6 and 7,
The drive duty D (lock-up clutch engagement pressure command value) of the lock-up solenoid 8 is controlled by the transmission controller 9, and the transmission controller 9 controls the throttle opening to detect the throttle opening TVO of the engine 3. Engine speed sensor 11 for detecting the signal from the speed sensor 10 and the engine speed Ne of the engine 3.
From the turbine rotation sensor 12 that detects the input rotation speed (turbine rotation speed) Nt of the automatic transmission 1, and the transmission output rotation sensor 13 that detects the output rotation speed No of the transmission output shaft 4. And the signal from the 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 other situations when determining whether the motion state of the vehicle is the deceleration state. be able to.

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

Regarding the lockup control, for example, from the throttle opening TVO and the output rotational speed No for each specific shift speed or each shift speed, a lockup region in which the torque increasing function and the torque fluctuation absorbing function by the torque converter 2 are unnecessary. In the control area such as whether it is operating in the
The drive control of the lockup solenoid 8 controls the torque converter 2 to be in a lockup state in the lockup region, and to release the torque converter 3 in the converter region to bring the torque converter 3 into the converter state. To do.

In order to detect the slip of the lockup 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 to them is used. It can be used, and here, the transmission controller 9 receives the engine speed Ne input to the transmission controller 9.
And the turbine rotation speed Nt are monitored, and a check is made to determine whether or not the value is close to a value at which the engagement of the L / U can be confirmed.

As an indication of the operating state of the vehicle,
In addition to the vehicle speed V calculated from the output rotation speed No, the throttle opening TVO, the engine rotation speed Ne, the engine intake air amount, the engine intake negative pressure, the auxiliary machine drive state, the differential state of the braking device, or these are obtained. Any one of the changing speed, the vehicle running load, and the engine torque is used.

FIG. 2 is a flow chart for explaining the first embodiment of the lock-up control device for an automatic transmission according to the present invention. This routine is for learning-correcting the lock-up engaging force when it is determined that the vehicle is in the decelerating traveling state and the lock-up off control is performed, and the slip rotation does not occur. First, in step S1, it is determined whether or not lockup off control should be performed. When performing the lockup off control, it is determined in step S2 whether or not the deceleration-time lockup engaging force learning flag is turned on, that is, whether or not the deceleration-time lockup clutch engaging force learning control is performed.

The lockup engagement force learning flag during deceleration is set to O.
If NO, it is confirmed in step S3 whether or not the deceleration lockup engagement force learning condition is satisfied. In the present embodiment, the transmission operating oil temperature obtained by the signal from the oil temperature sensor 14 (FIG. 1), its line pressure, the pilot pressure, and the control power supply voltage are used to indicate the lockup engagement force learning condition during deceleration. And either of

If the lock-up engagement force learning condition during deceleration is satisfied, it is determined in step S4 whether or not a learning start flag indicating that learning control is started is turned on, that is, a predetermined amount is locked. It is determined whether or not the up fastening force has been reduced. If the learning start flag is not ON, that is, it is OFF, step S5
At, the difference between the current lockup engagement force learning value during deceleration and the lockup engagement force reduction learning range during deceleration is updated as the new lockup engagement force learning value during deceleration, and the lockup engagement force learning value during deceleration is updated. I do. That is, control is performed to reduce the lock-up engagement force only once with a predetermined correction width (lock-up engagement force reduction learning width during deceleration).

Next, in step S6, the learning waiting time (this is the learning waiting time) to elapse before the slip occurrence confirmation control (which will be described later in step S14) is performed.
It is used in the subsequent step S11. ) Is read. In this case, the learning waiting time is set to a predetermined time in consideration of a delay in the change in the hydraulic pressure of the hydraulic system of the automatic transmission 1 (FIG. 1) after the lockup engagement force during deceleration is corrected to the open side by the reduced learning amount. Then, in step S7, the slip occurrence confirmation threshold value used in the subsequent step S14 (more specifically, step S61 in 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.
After the learning start flag is turned ON in step S9, that is, in steps S1 to
After it is decided to start the learning control in S9 and the data processing for that is completed, the deceleration lockup control for learning is performed in step S10 using the newly updated learning value.

After the deceleration lockup control for learning is completed, the learning waiting time measured by the learning waiting time timer (not shown) in step S11 is equal to the learning waiting time read in step S6. Determine if it has passed. That is, it is determined whether or not a predetermined time has elapsed, which allows for a delay in the hydraulic pressure change of the hydraulic system of the automatic transmission 1 (FIG. 1) after the lockup engagement force during deceleration is corrected to the open side by the learned amount.

When the learning waiting time measured by the learning waiting time timer (not shown) has not passed the learning waiting time read at step S6, the learning waiting time timer (not shown) at step S12. No.) is incremented. On the other hand, when the learning waiting time has elapsed, in step S13, it is in a waiting state for slip occurrence confirmation in subsequent step S14 (more specifically, steps S63 and S65 in FIG. 4). It is determined whether or not the slip occurrence confirmation waiting flag is turned on.

After completion of step S12 or step S13
If it is determined that the slip occurrence confirmation wait 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 is performed. (More details will be described in step S67 of FIG. 4.) It is determined whether or not it is ON. That is, in step S15, it is determined whether or not slip rotation has occurred as a result of updating the lockup engagement force learning value during deceleration in S5, that is, the lockup engagement force reduction learning during deceleration. Note that this step S14
Will be described in detail later using the routine of FIG.

The slip occurrence confirmation flag is OFF,
That is, when the occurrence of slip rotation is not confirmed, this logic is ended. On the other hand, if the slip occurrence confirmation flag is ON, it is considered that slip rotation has occurred because the lockup engagement force learning value during deceleration was updated in step S5, and in the next step S16,
The sum of the lockup engagement force learning value during deceleration updated in step S5 and the lockup engagement force reduction learning range during deceleration (that is, the lockup engagement force learning value before deceleration before update) is used as the lockup value during the next deceleration. By setting the fastening force learning value, the result of the current deceleration lockup fastening force reduction learning (that is, the deceleration lockup fastening force learning value updated in step S5) is rejected.

If it is determined in step S13 that the slip occurrence confirmation wait flag is OFF, that is, it is not in the slip occurrence confirmation waiting state, it is determined that slip rotation has not occurred, and lockup engagement force learning during deceleration is performed. The result (that is, the lockup engagement force learning value during deceleration updated in step S5) is used as the lockup engagement force learning value during deceleration for the next lockup control during deceleration.

When it is determined in step S13 that the slip occurrence confirmation waiting flag is OFF or after the processing in step S16, the main learning control end processing in steps S17 to S20 is started. In this case, first, in step S17, the lockup engagement force learning flag during deceleration is turned off.
Then, in step S18, the slip occurrence confirmation waiting flag is turned off, and then in step S19.
At step S20, the slip occurrence confirmation flag is turned off, and then at step S20, the learning start flag is turned off.
And then this logic ends.

When the lockup engaging force learning flag during deceleration is OFF in step S2, or in step S3
If the lockup engagement force learning condition during deceleration is not satisfied in (in this case, the lockup engagement force learning flag during deceleration is ON, that is, the vehicle is in the deceleration state and the lockup off control is performed. Even if), it is determined that the main learning control is not performed, and step S21
To turn off the lockup engagement force learning flag during deceleration,
Then, 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 lockup engagement force reduction learning width added to the deceleration lockup engagement force learning value updated in step S5 is added. By setting the lockup engagement force learning value at the next deceleration,
The result of the current deceleration lockup engagement force reduction learning is rejected, and thereafter, in step S24, the learning start flag is turned off, and the learning control is interrupted.

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

When it is determined in step S1 that lockup off control is not to be performed, it is determined in step S26 whether or not lockup control during deceleration is to be performed. When it is determined that the lockup control during deceleration is performed, the lockup engagement force learning flag during deceleration is turned on in step S27, the slip occurrence confirmation flag is turned off in step S28, and the lockup off control is performed. Prepare Then, step S29
At, the lockup control during deceleration is performed, and then this logic is ended.

If it is determined in step S26 that lockup control during deceleration is not performed, other lockup control is performed in step S30.

According to the present embodiment, when it is determined that the vehicle motion state is the deceleration running state and the lockup off control is performed, and the slip rotation does not occur, the current deceleration lockup engagement force learning value is used. , Decrease lock-up engaging force reduction during deceleration The difference between the learning width and the new lock-up engaging force learning value during deceleration is used as the new lock-up engaging force learning value during deceleration to reduce the lock-up engaging force. It is possible to significantly suppress the slip that occurs at the time of lockup in the inertia running state.

When the deceleration lock-up engagement force learning condition is judged, and if the deceleration lock-up engagement capacity learning condition is not satisfied, the learning correction of the lock-up engagement force is prohibited, so that a suitable deceleration time is obtained. The lock-up fastening force can be learned.

FIG. 3 is a flow chart for explaining the second embodiment of the lockup control device for an automatic transmission according to the present invention. This routine is to learn and correct the lock-up engaging force when it is determined that the vehicle is in the decelerating traveling state and the lock-up control is being performed, and the slip rotation does not occur. Also, this is
If the occurrence of slip rotation is confirmed before the lapse of a predetermined time after the completion of the lockup transition control during deceleration and it is determined that the lockup engagement force learning condition during deceleration is satisfied, the lockup engagement is performed by the predetermined amount. The control for increasing the force is performed, the lockup engagement capacity in the next decelerating traveling state is learned and corrected, and the lockup is turned off during deceleration.

First, in step S31, it is determined whether or not lockup control during deceleration is to be performed. When it is determined that the lockup control during deceleration should be performed, it is confirmed in step S32 whether or not this routine is the first time since the lockup control during deceleration is started. 1
If it is the first time, in step S33, the learning waiting time (which will be used in step S35 later) that should 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 the hydraulic pressure change of the hydraulic system of the automatic transmission 1 (FIG. 1) after the lockup engagement force during deceleration is corrected to the open side by the reduced learning amount. Then, in step S34, a learning waiting time timer (not shown) for measuring the current learning waiting time is initialized to perform initialization for starting learning control.

When it is determined in step S32 that it is not the first time, that is, it is the second time or more after the lockup control during deceleration is started, steps S3 and S4.
Skip. Therefore, the learning waiting time is not read and the learning waiting time timer (not shown) is not initialized.

If it is determined in step S32 that it is not the first time or after the learning waiting time timer (not shown) is initialized in step S34, it is measured by the learning waiting timer (not shown) 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 elapsed, which allows for a delay in the hydraulic pressure change of the hydraulic system of the automatic transmission 1 (FIG. 1) after the lockup engagement force during deceleration is corrected to the open side by the learned amount.

When the learning waiting time measured by the learning waiting time timer (not shown) has not passed the learning waiting time read at step S33, the learning waiting time timer (not shown) at step S36. No.) is incremented and time elapses. On the other hand, when the learning waiting time has elapsed, in step S37, it is confirmed whether or not the deceleration lockup engagement force learning condition is satisfied. Also in this embodiment, the transmission operating oil temperature obtained by a signal from the oil temperature sensor 14 (FIG. 1), its line pressure, pilot pressure, and control power supply voltage are used as the conditions for learning the lockup engagement force during deceleration. And either of

If the lockup engagement force learning condition during deceleration is not satisfied, the lockup engagement force learning flag during deceleration, which indicates whether or not to learn the engagement force of the lockup clutch during deceleration, is turned off in step S38. And then
The learning control thereafter is canceled. On the other hand, when the deceleration lock-up engagement force learning condition is satisfied, whether or not the learning start flag indicating that the learning control is started is turned on in step S39, that is, a predetermined amount is locked. It is determined whether or not the up fastening force has been reduced. If the learning start flag is not ON, that is, it is OFF, in step S40, the difference between the current deceleration lockup engagement force learning value and the deceleration lockup engagement force decrease learning width is set to the new deceleration lock. As the up-engagement force learning value, the lock-up engagement force learning value during deceleration is updated. That is, control is performed to reduce the lock-up engagement force only once with a predetermined correction width (lock-up engagement force reduction learning width during deceleration).

Next, in step S41, the slip occurrence confirmation threshold value used in the subsequent step S46 (more specifically, step S61 in FIG. 4) is read, and in step S42, the lockup engagement force learning flag during deceleration. Is turned on, and in step 43, the learning start flag is turned on to initialize the learning control and set the flag. 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 in steps S31 to S43 is completed, that is, after the learning waiting time timer (not shown) is incremented in step S36, and the lockup engagement force flag during deceleration is turned off in step S38. , The learning start flag is set to O in step S39.
After it is determined to be FF or after the learning start flag is turned on in step S43, lockup control during deceleration is performed in step S44.

Then, in step S45, it is confirmed whether or not the lockup engagement force learning flag during deceleration is ON, and it is determined whether or not the lockup engagement force learning during deceleration is carried out. When 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 ON, that is, if it is determined that lockup during deceleration is to be performed for learning, slip generation confirmation control is performed in step S46 to determine whether or not slip rotation is currently occurring. To do. Note that this step S46 will be described later in detail using the routine of FIG.

Then, in step S47, it is determined whether or not the slip occurrence confirmation flag (in more detail, described in step S67 of 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 ending 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 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 lockup engagement force learning value during deceleration was updated in step S40, and the lockup engagement during deceleration updated in step S40. This time, the sum of the force learning value and the learning range for lockup engagement force reduction during deceleration (that is, the lockup engagement force learning value before deceleration before update) is set as the next lockup engagement force learning value during deceleration. The result of the deceleration lockup engagement force reduction learning (that is, the deceleration lockup 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 lockup engagement force learning value during deceleration is insufficient, and the original lockup engagement force learning value during deceleration is decelerated. The lockup engagement force increase learning during deceleration is performed by setting the sum of the time lockup engagement force increase learning width as the next lockup engagement force learning value during deceleration.

After rejecting the lockup engagement force reduction learning result during deceleration in step S49, or in step S50.
After the lockup engagement force increase learning during deceleration is performed in step S11, the main learning control ending process of steps S51 to S53 is performed. 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 deceleration lockup control is switched to the deceleration lockup off control to avoid slip rotation during the deceleration lockup control. finish.

If it is determined in step S31 that 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 next learning control during deceleration is performed. Prepare for

According to this logic, it is determined that the vehicle motion state is the deceleration running state and the lockup control is performed, and the slip rotation does not occur after a predetermined time has elapsed after the deceleration lockup transition control is completed. In this case, the difference between the current lockup engagement force learning value during deceleration and the lockup engagement force reduction learning range during deceleration is subtracted as the new lockup engagement force learning value during deceleration, and the lockup engagement force learning value during deceleration is updated. By performing the above, it is possible to significantly suppress the slip at the time of lockup in the coasting state that occurs due to the reduction of the lockup engagement force.

Further, when the deceleration lock-up engagement force learning condition is judged, and when the deceleration lock-up engagement capacity learning condition is not satisfied, the learning correction of the lock-up engagement force is prohibited, so that a suitable deceleration time is obtained. The lock-up fastening force learning can be performed.

Further, when the occurrence of slip rotation is confirmed before a predetermined time has elapsed after the end of the lockup transition control during deceleration, and it is determined that the lockup engagement capacity learning condition during deceleration is satisfied, the original The sum of the lockup engagement force learning value during deceleration and the lockup engagement force increase learning range during deceleration is used as the next lockup engagement force learning value during deceleration, and by switching to lockup off control during deceleration, It is possible to more appropriately learn and correct the lock-up engagement capacity in the decelerating traveling state, and by this, the slip at the lock-up in the coasting state that occurs due to the reduction of the lock-up engaging force is further significantly suppressed. be able to.

FIG. 4 is a flow chart for explaining the slip occurrence confirmation control in the flow charts of FIGS.
This logic is executed in step S14 of FIG. 2 and step S46 of FIG. 3, and it has elapsed after the slip rotation speed is greater than the slip occurrence confirmation threshold value and the slip rotation speed is less than the slip occurrence confirmation threshold value. The slip rotation is detected when the slip occurrence confirmation waiting time has elapsed.

First, in step S61, it is determined whether or not the current slip rotation speed is larger than a slip occurrence confirmation threshold value, which is a measure of slip rotation, and whether or not slip rotation has occurred is checked. If the current slip rotation speed 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, and then step S63. 2, the slip occurrence confirmation wait flag used in step S13 of FIG.
The control is transferred to the slip occurrence confirmation waiting state by setting N.

If the current slip rotation speed 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 waiting timer (not shown) is initialized. Then, in step S65, the slip occurrence confirmation wait flag is turned off to prepare for the occurrence of slip rotation.

After the slip occurrence confirmation wait flag is turned on in step S63, the time measured by the slip occurrence confirmation wait time timer (not shown) is compared with the slip occurrence wait time to determine the duration of slip rotation occurrence. Check. 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 the slip rotation occurrence is sufficiently continued, the slip occurrence confirmation flag is turned on in step S67. The occurrence of slip rotation shall be 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 the slip rotation occurrence is not sufficiently continued, step S68. At, the slip occurrence confirmation waiting time timer (not shown) is incremented to measure the duration. When the above control is completed, the process returns to the main routine of FIG.

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

[Brief description of 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 first embodiment of a lockup control device for an automatic transmission according to the present invention.

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

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

[Explanation of symbols]

1 automatic transmission 2 Torque converter (T / C) 3 engine 4 output shafts 5 control valves 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 speed No Output shaft speed Nt turbine speed TVO throttle opening

─────────────────────────────────────────────────── ─── Continuation of front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) F16H 61/14

Claims (7)

(57) [Claims] 1. A lockup control device for an automatic transmission having a torque converter capable of establishing a lockup state in which input and output are directly connected by a lockup clutch in a transmission system, wherein an engagement capacity of the lockup clutch is arbitrarily set. Lockup clutch engagement capacity control means, slip detection means for detecting slip of the lockup clutch, motion state detection means for detecting the motion state of the vehicle, and lockup engagement or disengagement depending on the motion state of the vehicle. Lockup engagement / release determination means for determining, and the motion state detection means detects that the vehicle is in a decelerating traveling state, and the lockup engagement / release means should release the lockup. Is detected, and by the slip detection means, If slip of the lock-up clutch is not confirmed, before starting the normal lock-up release control, control is performed to reduce the lock-up engagement capacity by a predetermined amount, and as a result of the lock-up engagement capacity reduction control, When the slip-up slip is detected by the slip detection means, the lock-up engagement capacity before the lock-up engagement capacity lowering control is stored, and
When the slip 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 decelerated traveling state is learned and corrected. A lockup control device for an automatic transmission, which is characterized in that 2. A lockup engagement capacity during deceleration, which judges a lockup engagement capacity learning condition during deceleration, and prohibits learning correction of the lockup engagement capacity when the lockup engagement capacity learning condition during deceleration is not satisfied. 2. The lockup control device for an automatic transmission according to claim 1, further comprising learning condition determining means. 3. The slip detection means has a predetermined waiting time after 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. The lockup control device for an automatic transmission according to claim 1 or 2, wherein a slip of the lockup clutch is detected when the value exceeds the limit. 4. A lockup control device for an automatic transmission having a torque converter in a transmission system capable of establishing a lockup state in which input and output are directly connected by a lockup clutch, and an engagement capacity of the lockup clutch is arbitrarily set. Lockup clutch engagement capacity control means, slip detection means for detecting slip of the lockup clutch, motion state detection means for detecting the motion state of the vehicle, and lockup engagement or disengagement depending on the motion state of the vehicle. Lockup engagement / release determination means for determining, and the motion state detection means detects that the motion state of the vehicle shifts to a decelerating traveling state, and lockup is engaged by the lockup engagement / release means. It is detected that it is in a proper state, and the slip detecting means. Therefore, when slippage of the lockup clutch is not confirmed after a predetermined time has elapsed from the end of the lockup transition control during deceleration, control is performed to reduce the lockup engagement capacity by a predetermined amount, and the lockup engagement capacity decrease control is performed. As a result, when the slip-up slip is detected by the slip detector, the lock-up engagement capacity before the lock-up engagement capacity lowering control is stored, whereas the slip-up slip is not detected by the slip detector. In this case, the lock-up engagement capacity after the lock-up engagement capacity reduction control is stored, and the lock-up engagement capacity in the next decelerating traveling state is learned and corrected. apparatus. 5. A deceleration lockup engagement capacity learning condition for determining deceleration lockup engagement capacity, and prohibiting learning correction of the lockup engagement capacity when the deceleration lockup engagement capacity learning condition is not satisfied. The lockup control device for an automatic transmission according to claim 4, further comprising learning condition determination means. 6. The slip detection means confirms the slip of the lockup clutch before a predetermined time elapses after the completion of the deceleration lockup transition control, and the deceleration lockup engagement capacity learning condition determination means. When it is determined that the lockup engagement capacity learning condition during deceleration is satisfied, control is performed to increase the lockup engagement capacity by a predetermined amount, and the lockup engagement capacity in the next decelerated running state is learned and corrected, 6. The lockup control device for an automatic transmission according to claim 5, wherein the lockup engagement / release determination means is configured to release the lockup during deceleration. 7. The slip amount of the lock-up clutch is larger than a predetermined threshold value, and the time elapsed after the slip amount of the lock-up clutch falls below a predetermined threshold value exceeds a predetermined waiting time. 7. The lockup control device for an automatic transmission according to claim 4, wherein slip of the lockup clutch is detected.