JP2002340162A - Oil pressure control device for automatic transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To linearly change the oil supply quantity in response to a change of the continuous time for periodical oil supply in the air discharge control for discharging the air mixed in a hydraulic circuit by periodically supplying the oil to a friction engaging element to be released. SOLUTION: When termination timing of the continuous time does not coincide with the repeat period t1, a requested supply time t3 corresponding to the odd time is computed on the basis of the time rate in relation to the period t1. When the termination timing comes during the supply of the oil, the oil is continuously supplied for the requested supply time t3 to supply the oil of under supply after the termination timing. When termination timing comes during the non-supply of the oil, the oil is supplied for the requested supply time t3 after the supply starting timing.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic control device for an automatic transmission, and more particularly, to a technique for controlling a supply amount of oil to a friction engagement element by periodically controlling oil supply.

[0002]

2. Description of the Related Art Conventionally, in a hydraulic control device for an automatic transmission that hydraulically controls the engagement and disengagement of a friction engagement element, a friction engagement element to be released from a request for a shift speed at that time is provided. There is known a configuration in which oil mixed in a hydraulic circuit of the friction engagement element is discharged by periodically supplying oil within a range not reaching a fastening state (Japanese Patent Application Laid-Open No. 10-1).
69964).

[0003]

In the above-described air discharge control, when the supply time of the oil is controlled by controlling the duration of the periodical supply of the oil, the oil supply is controlled from the start of the oil supply. The control is stopped when the elapsed time reaches a predetermined time. However, a slight difference in the end timing causes a large deviation in the oil supply amount (oil pressure). There was a problem that it was difficult to do.

For example, as shown in FIG. 9, the periodical oil supply is terminated at the timing "A" immediately after the oil supply is stopped, and the period "B" immediately before the start of the next oil supply. ), The period of time during which the periodic oil supply is performed is different, but the sum of the oil supply times is the same, so the oil supply amount (oil pressure)
Will be the same.

[0005] Further, the oil is supplied between the case where the oil supply is terminated at the timing "B" immediately before the start of supply and the case where the oil supply is terminated at the timing "C" immediately after the supply of the oil is performed. Since the total sum of the time periods differs, even if the time difference between “A” and “B” is almost the same, the amount of supplied oil (oil pressure) will greatly differ. As described above, the dead zone of the oil supply amount (oil pressure) with respect to the change in the duration is large, and the oil supply amount (oil pressure) is greatly changed stepwise. (Hydraulic pressure) cannot be finely adjusted based on the duration.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has an automatic transmission in which the amount of oil supply (oil pressure) can be finely controlled by controlling the duration of periodic oil supply. To provide a hydraulic control device for the machine.

[0007]

According to the first aspect of the present invention, the oil is supplied to the friction engagement element for a predetermined time every predetermined repetition period, and the duration of the periodic supply control of the oil is controlled. In the hydraulic control device for an automatic transmission configured to control an oil supply amount to the friction engagement element based on the oil supply time, the oil supply time is corrected and controlled according to an end timing of the continuation time with respect to the repetition cycle. And

According to this configuration, the sum of the supply times up to the end timing greatly differs depending on whether the end timing of the duration with respect to the repetition period is immediately after the supply is stopped or immediately before the start of the supply. Therefore, by correcting and controlling the supply time according to the end timing, the total of the supply time can be more finely changed with respect to the change in the duration.

According to the second aspect of the present invention, the ratio of the time from the beginning of the repetition period to the end timing of the continuation time with respect to the repetition period is calculated, and the supply time of the oil is corrected and controlled according to the ratio. The configuration was adopted. According to such a configuration, the time from the beginning of the repetition cycle to the end timing of the duration is measured, and the ratio of the measurement time to the repetition cycle is calculated. The supply time is corrected and controlled based on the time ratio indicating the request.

According to the third aspect of the present invention, oil is additionally supplied after the end of the duration according to the end timing. According to this configuration, by supplying the oil after the end of the duration, the supply time is additionally corrected for the total of the supply times up to the end timing, and the supply time after the end timing is changed according to the difference in the end timing. Change the total of the supply time including that.

According to the present invention, the ratio of the elapsed time from the immediately preceding supply stop to the end of the continuation time to the repetition cycle is calculated, and the required supply time is calculated from the ratio and the predetermined time. The oil is additionally supplied after the end of the duration based on the required supply time. According to such a configuration, when the oil is supplied for a fixed time per repetition cycle,
The supply time corresponding to a period shorter than one cycle is obtained by multiplying the ratio of the actual elapsed time to one cycle by the supply time per cycle, and this is set as a required supply time. Is added after the end of the duration.

In the invention described in claim 5, when the end timing is during the oil supply period, the oil is continuously supplied after the end timing for a time obtained by subtracting the supply time up to the required supply time. On the other hand, when the end timing is during the oil non-supply period, the oil is supplied for the required supply time from the next supply start timing.

According to this configuration, if the end timing is during the oil supply period, the required supply time corresponding to the last period of less than one cycle, excluding the supply time up to the end timing, is calculated after the end timing. If the supply is continued, the oil is supplied for the required supply time. On the other hand, if the end timing is during the non-supply period of oil, it means that the oil was not supplied within the last period of less than one cycle. The oil is supplied only for the supply time.

According to the present invention, when the friction engagement element is to be released, the oil is supplied by the periodic supply control of the oil, and the supply of the oil causes the oil pressure of the friction engagement element to be released. It is configured to discharge air mixed in the circuit. According to this configuration, when the oil is supplied to the friction engagement element by the periodic oil supply control and the air mixed in the hydraulic circuit of the friction engagement element is discharged, the periodic supply control is continued. The oil supply time is corrected according to the end timing of the time.

[0015]

According to the first aspect of the invention, the supply time is corrected in accordance with the difference in the end timing of the periodic supply control, so that the total of the supply time can be calculated with respect to the difference in the duration.
That is, there is an effect that the supply amount of oil can be finely controlled. According to the second aspect of the present invention, the length of the duration is less than the last one cycle,
There is an effect that the oil supply time can be accurately corrected, and the oil supply time can be more finely controlled with respect to a change in the duration.

According to the third aspect of the present invention, by the oil supply control after the end of the duration, fine adjustment is added to the stepwise change of the total of the supply time within the duration. Thus, there is an effect that the supply time of the oil can be more finely controlled with respect to the change in the duration time. According to the fourth aspect of the present invention, the fraction of the duration that is less than the repetition period is converted into the oil supply time, so that the total oil supply time changes linearly with the change in the duration. There is an effect that can be.

According to the fifth aspect of the present invention, by judging the correlation between the end timing of the duration and the regular repetition cycle, it is possible to supply the additional oil in accordance with the repetition cycle. effective. According to the invention described in claim 6, the supply amount of oil for discharging the air mixed in the hydraulic circuit can be finely controlled based on the duration of the periodic oil supply control, and the oil supply is released. There is an effect that the air can be reliably discharged without fastening the frictional engagement elements to be fastened.

[0018]

Embodiments of the present invention will be described below. FIG. 1 shows a drive system of a vehicle according to an embodiment. An automatic transmission 3 is connected to an output shaft of an engine 1 via a torque converter 2.
The drive shaft of the vehicle (not shown) is driven to rotate by the output shaft of the vehicle.

FIG. 2 is a skeleton showing a transmission mechanism of the automatic transmission 3. The transmission mechanism includes two sets of planetary gears G1, G2 and three sets of multi-plate clutches (high clutch H
/ C, reverse clutch R / C, low clutch L /
C) One set of brake bands 2 & 4 / B, one set of multiple disc brakes (low & reverse brake L & R / B), and one set of one-way clutch L / OWC.

The two sets of planetary gears G1 and G2 are simple planetary gears including sun gears S1 and S2, ring gears r1 and r2, and carriers c1 and c2, respectively. The sun gear S1 of the planetary gear set G1 has a reverse clutch R /
C is configured to be connectable to the input shaft IN, and is configured to be fixable by the brake bands 2 & 4 / B.

The sun gear S2 of the planetary gear set G2 is directly connected to the input shaft IN. The carrier c1 of the planetary gear set G1 is configured to be able to be coupled to the input shaft IN by a high clutch H / C, while the ring gear r2 of the planetary gear set G2 is connected to the carrier of the planetary gear set G1 by a low clutch L / C. The carrier c1 of the planetary gear set G1 can be fixed by a low & reverse brake L & R / B.

A ring gear r1 of the planetary gear set G1 and a carrier c2 of the planetary gear set G2 are directly and integrally connected to the output shaft OUT. In FIG. 2, reference numeral 21 denotes an oil pump (hydraulic pump) driven by the engine 1 and supplying hydraulic oil to the automatic transmission. In the transmission mechanism having the above-described structure, the first to fourth forward speeds
As shown in FIG. 3, the speed and the reverse R are realized by a combination of the engaged / released state of each clutch / brake (friction engagement element).

In FIG. 3, a circle indicates a fastened state, and a part without a symbol indicates a released state. In particular, the low & reverse brake L at the first speed is used.
The fastening state indicated by a black circle of & R / B indicates fastening only in one range. The engagement / disengagement logic of the friction engagement element is realized by a combination of ON / OFF of the shift solenoid (A) 5 and the shift solenoid (B) 6 inserted in the shift control valve 4 shown in FIG. (See FIG. 4).

A line pressure solenoid 7 is inserted in the control valve 4, and the line pressure of the control valve 4 is controlled by the line pressure solenoid 7. The shift solenoid (A) 5, the shift solenoid (B) 6, and the line pressure solenoid 7 are controlled by an A / T controller 11. The A / T controller 11 includes an ATF temperature sensor 12 for detecting the temperature of an ATF (Automatic Transmission Fluid (hereinafter, referred to as ATF)), and a throttle valve for interlocking an accelerator pedal (not shown) to throttle the intake of the engine 1. 8
, An output shaft rotation sensor 14 for detecting an output shaft rotation speed No of the automatic transmission, a turbine rotation sensor 15 for detecting a turbine rotation speed Nt (input shaft rotation speed), a shift knob The detection signal is input from the inhibitor switch 16 for detecting the range position selected by the operation described above.

The A / T controller 11
While performing normal shift control based on the various detection signals described above, by executing a control program shown in the flowchart of FIG. 5, the hydraulic pressure of the predetermined friction engagement element (high clutch H / C in the present embodiment) is increased. Control to discharge air (bubbles) mixed into the circuit. In the flowchart of FIG. 5, in step S1, it is determined whether or not an execution permission condition of the air discharge control is satisfied.

For example, the following conditions (1) to (3) are determined as the execution permission conditions. (1) N first after the ignition switch is turned on
D range (drive range) switched from the range (neutral range). (2) Line pressure control (ND select control) performed at a predetermined time immediately after switching from the N range to the D range
Has been completed.

(3) The first speed is steady when there is no shift request. When it is determined that all of the above conditions (1) to (3) are satisfied, the process proceeds to step S2. In step S2, a repetition period t1 when hydraulic pressure is periodically supplied for air discharge control, a hydraulic pressure supply time t2 per the repetition period t1, and a duration T for performing periodic hydraulic pressure supply are set. .

The repetition cycle t1, the supply time ratio, and the continuation time T are set, for example, according to the oil temperature. In step S3, it is determined whether or not the continuation time T has elapsed since the execution condition was satisfied. If it is determined in step S3 that the continuation time T has not elapsed, the process proceeds to step S3.
4 and the repetition period t set in step S2
1. On the basis of the supply time t2, oil is periodically supplied to the high clutch H / C, which is a friction engagement element to be released in the first speed state.

Specifically, the shift solenoid (A)
The switch 5 and the shift solenoid (B) 6 are both turned off for a predetermined time t2 at a constant repetition cycle t1 (see FIG. 6). In first gear, the shift solenoid (A)
The shift solenoid (A) 5 and the shift solenoid (B) 6 are controlled to be in the ON state, the high clutch H / C is released, and the low clutch L / C is engaged. B) The state where both 6 are OFF corresponds to the state of the third speed, and at the third speed, the low clutch L /
C and the high clutch H / C are engaged (see FIGS. 3 and 4).

Accordingly, the shift solenoid (A) 5 and the shift solenoid (B) 6 are both turned off for the supply time t2 at every repetition cycle t1, thereby enabling the high clutch H / C to be released at the first speed. On the other hand, the supply of the hydraulic pressure is periodically repeated, and the air supplied to the hydraulic circuit of the high clutch H / C is discharged by the periodic supply of the hydraulic pressure.

In step S5, the repetition period t1
The elapsed time from the timing when the supply of the hydraulic pressure to the high clutch H / C is stopped (start of the cycle) to the present time is measured, and the ratio R of the measurement time to the repetition cycle t1 is calculated. On the other hand, if it is determined in step S3 that it is the end timing of the duration T, the process proceeds to step S3.
6, the oil is supplied only for the supply time t2, and the shift solenoid (A) 5 and the shift solenoid (B) 6 are turned on.
It is determined whether or not the timing of returning to the state (repetition cycle) matches the end timing of the duration T.

Here, when the end timing of the continuation time T coincides with the oil supply stop timing by the ordinary repetitive control, the routine proceeds to step S7, where the periodic supply of oil is immediately stopped. On the other hand, when the end timing of the continuation time T does not coincide with the oil supply stop timing by the normal repetitive control, step S
Proceed to 8.

In step S8, it is determined whether or not the end time of the continuation time T has been reached in the oil supply state by the normal repetitive control. In step S8, when it is determined that the end time of the duration T has come in a state where the oil is not supplied by the normal repetitive control, step S9 is performed.
Proceed to. In step S9, the supply time t2 in the repetitive control is multiplied by the ratio R, and the result is set as a required supply time t3. From the next supply start timing corresponding to the repetition period t1, the required supply time t3 is calculated. Shift solenoid (A) 5 and shift solenoid (B)
6, the oil is supplied to the high clutch H / C for the required supply time t3 after the continuation time T (see FIG. 7).

For example, from the time when the shift solenoid (A) 5 and the shift solenoid (B) 6 are returned to the ON state (when the hydraulic pressure supply is stopped), the repetition period t1
When half (50%) of the time has elapsed, the duration time T ends, and if the supply of oil to the high clutch H / C is stopped at that time, the repetition period t1
The shift solenoid (A) 5 and the shift solenoid (B) 6 are both turned off for a required supply time t3, which is half the supply time t2, from the start timing immediately after the end of the duration T according to the above.

If it is determined in step S8 that the end time of the duration T has come in the oil supply state by the normal repetitive control, the process proceeds to step S10.
In step S10, the supply time t in the repetitive control
2 is multiplied by the ratio R, and the result is set as a required supply time t3. The oil supply is continuously stopped after the end timing so that the supply of the oil is stopped after the required time t3 from the start of the current supply state. (See FIG. 8).

For example, when 75% of the repetition period t1 has elapsed, the duration T ends, and at that time, the supply of oil to the high clutch H / C is performed for 50% of the original time t2. , The required supply time t3 is calculated as 75% of the original supply time t2, and the oil has been supplied by 50% by that time.
The oil is continuously supplied for the time corresponding to 5% even after the end of the duration time T.

That is, the supply time t per repetition cycle t1
2 is determined, the required supply time that should correspond to an odd time less than one cycle immediately before the end timing of the duration T is multiplied by the ratio of the odd time to one cycle and the original supply time t2. To be determined. If the supply of the oil is performed at the end timing of the duration T, the shortage is continuously supplied. If the supply of the oil is not performed at the end timing of the duration T, the next start is performed. The oil is supplied only for a time corresponding to an odd time from the timing.

According to the above configuration, even if the duration T is changed with a resolution of one cycle or less, the total oil supply time can be changed linearly with respect to the change in the duration T.
By setting the duration time T, the amount of oil supply to the friction engagement element can be finely controlled, and the optimal amount of oil for air discharge can be supplied to the friction engagement element (high clutch). .

In the above-described embodiment, in the periodic oil supply control for air discharge, the supply time is corrected in accordance with the end timing. However, the same correction control is performed except for the air discharge. Obviously, the present invention can be applied to the periodic supply control of the target oil.

[Brief description of the drawings]

FIG. 1 is a system diagram showing a vehicle drive system according to an embodiment.

FIG. 2 is a skeleton diagram showing a transmission mechanism in the embodiment.

FIG. 3 is a diagram showing combinations of engagement states of frictional engagement elements at each shift speed in the embodiment.

FIG. 4 is a diagram showing a combination of ON and OFF of shift solenoids A and B at each shift speed in the embodiment.

FIG. 5 is a flowchart illustrating an embodiment of air discharge control.

FIG. 6 is a time chart showing basic control of a shift solenoid for discharging air.

FIG. 7 is a time chart showing correction control of the supply time when the end time of the duration is a non-supply state of oil.

FIG. 8 is a time chart showing supply time correction control when the end time of the duration is an oil supply state.

FIG. 9 is a time chart for explaining a conventional problem.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Engine 2 ... Torque converter 3 ... Automatic transmission 4 ... Control valve 5 ... Shift solenoid (A) 6 ... Shift solenoid (B) 11 ... A / T controller 12 ... ATF temperature sensor 13 ... Throttle opening degree sensor 14 ... Output Shaft rotation sensor 15 Turbine rotation sensor 16 Inhibitor switch G1, G2 Planetary gear H / C High clutch R / C Reverse clutch L / C Low clutch 2 & 4 / B Brake band L & R / B Low and reverse brake L / OWC… One-way clutch

Claims (6)

[Claims] An oil is supplied to a friction engagement element for a predetermined time every predetermined repetition period, and an amount of oil supplied to the friction engagement element based on a duration of the periodic supply control of the oil. A hydraulic control device for an automatic transmission, wherein the hydraulic supply time is corrected according to an end timing of the duration with respect to the repetition cycle. 2. The method according to claim 1, wherein a ratio of a time from a start of the repetition period to an end timing of the duration is calculated with respect to the repetition period, and the supply time of the oil is corrected and controlled according to the ratio. Item 2. A hydraulic control device for an automatic transmission according to Item 1. 3. The hydraulic control device for an automatic transmission according to claim 1, wherein an additional oil is supplied after the end of the duration according to the end timing. 4. A required supply time is calculated from the ratio of the elapsed time from the immediately preceding supply stop to the end timing of the continuation time to the repetition period, and the required supply time is calculated from the ratio and the predetermined time. 2. The hydraulic control device for an automatic transmission according to claim 1, wherein the oil is additionally supplied after the end of the duration based on the following. 5. When the end timing is during the oil supply period, oil is continuously supplied after the end timing for a time obtained by subtracting the supply time up to the required supply time from the required supply time. 5. The hydraulic control device for an automatic transmission according to claim 4, wherein when the oil is not supplied, the oil is supplied for the required supply time from the next supply start timing. 6. In a state in which the friction engagement element is to be released, oil is supplied by periodic supply control of the oil, and the air mixed in the hydraulic circuit of the friction engagement element by the supply of the oil is supplied. 2. The method according to claim 1, wherein the discharge is performed.
The hydraulic control device for an automatic transmission according to any one of claims 5 to 5.