JP2002081536A - Control device for automatic transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To converge racing in a short time in an automatic transmission for changing speed by changing engagement of different friction engagement elements while controlling accumulator back pressure. SOLUTION: When generation of racing is detected at the time of up-shifting from a second gear speed to a third gear speed for engaging a high clutch H/C simultaneously as a brake band 2 and 4/B is released, a shift solenoid (B) is returned to an ON-state in the second gear speed to supply D-range pressure to the release side, and accumulator back pressure on the release side is increased by correction control to a 2 and 4/B duty solenoid, while a 2 and 4/B timing solenoid to control a timing valve to decide drain timing of the release side accumulator back pressure is turned OFF for prohibiting the drain action. By detecting convergence of racing, the correction control condition to racing is restored to a normal condition.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for an automatic transmission, and more particularly, to a technique for suppressing the occurrence of idling during speed change control.

[0002]

2. Description of the Related Art Conventionally, there has been known an automatic transmission configured to perform a shift by changing a friction engagement element that simultaneously performs engagement control and release control of two different friction engagement elements. As a shift control device for performing the shift change of the friction engagement element, for example, Japanese Patent Laid-Open No. 11-03032
As disclosed in Japanese Patent Laid-Open No. 4 (1999) -1994, an accumulator is provided in a supply path of oil to each friction engagement element, and a gradient of an increase or a decrease in hydraulic pressure is suppressed by controlling a back pressure of the accumulator. There was something.

[0003] On the other hand, in the above-described shift control device for performing a shift change of the friction engagement element, as a technique for suppressing the occurrence of idling at the time of shifting, Japanese Patent Laid-Open Nos. 7-012210, 5-039843 and JP 2000
There was one disclosed in Japanese Patent Application Publication No. 055180. In the device disclosed in Japanese Patent Application Laid-Open No. H07-122210, a pressure switch detects an increase in the hydraulic pressure of the engagement-side frictional engagement element and determines the timing for releasing the hydraulic pressure of the release-side frictional engagement element. I have.

[0004] Further, in Japanese Patent Laying-Open No. 5-039843, when the slip amount of the disengagement side frictional engagement element is equal to or more than a threshold value, the hydraulic pressure of the disengagement side frictional engagement element is increased. When the rate of change of the slip amount is 0 or less, the hydraulic pressure of the disengagement-side friction engagement element is reduced. Further, in Japanese Patent Application Laid-Open No. 2000-0555180, the stroke completion of the engagement-side friction engagement element is predicted, and the line pressure is reduced by timing the stroke completion.

[0005]

However, the configuration using a pressure switch has a problem that the system cost of the automatic transmission increases because the pressure switch is generally expensive. In the configuration in which the hydraulic pressure is controlled in accordance with the slip amount of the release-side friction engagement element, the shift time is extended because the hydraulic pressure of the release-side friction engagement element is controlled to converge so as to maintain the small slip amount. As a result, there is a possibility that the shifting performance is deteriorated.

Further, in a configuration in which the line pressure is reduced by timing the completion of the stroke of the engagement-side frictional engagement element,
Due to a prediction error at the time of completion of the stroke, the occurrence of idling cannot be suppressed stably, and a decrease in the line pressure (original pressure) in the torque phase causes a decrease in the responsiveness of the clutch hydraulic pressure. There was a possibility that it would promote the blowing.

Further, as disclosed in Japanese Patent Application Laid-Open No. H11-030324, the timing of draining the accumulator back pressure of the disengagement side frictional engagement element is controlled based on the accumulator back pressure of the engagement side frictional engagement element. In this configuration, the torque capacity on the release side can be reduced at the timing when the torque capacity on the engagement side is secured by setting the back pressure on the accumulator on the engagement side optimally. Since the oil in the joint element and the hydraulic path escapes, the hydraulic response on the engagement side is slowed down at the time of shifting for the first time after the start of the operation, and there is a possibility that a large air blow is generated.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and in an automatic transmission for performing a shift change by controlling the back pressure of an accumulator, the cost does not increase and the shift time is not prolonged. It is an object of the present invention to be able to stably suppress the occurrence of air blowing.

[0009]

Therefore, according to the first aspect of the present invention, while controlling the back pressure of the accumulator, the frictional engagement element for simultaneously performing the engagement control and the release control of two different frictional engagement elements is controlled. In a control device for an automatic transmission configured to perform a shift by changing a gear, when an idling is detected during the shift, oil pressure is supplied to the disengagement-side friction engagement element, and the release-side friction engagement element is controlled. The accumulator back pressure is increased and corrected.

[0010] According to this configuration, the state in which the hydraulic pressure on the release side is drained is switched to the state in which the hydraulic pressure is supplied to the release side, and the release side accumulator back pressure is increased and corrected, so that the frictional engagement element on the release side is increased. The squeezing pressure is raised with good response to achieve the convergence of the idling condition due to insufficient torque capacity. According to the second aspect of the invention, the shift solenoid that switches on and off the supply and discharge of oil to and from each friction engagement element and the back pressure of the accumulator interposed in the oil supply path to each friction engagement element A duty solenoid to be controlled, a timing valve for determining a timing for draining the accumulator back pressure of the release-side friction engagement element in accordance with a rise in the operating pressure of the engagement-side friction engagement element, and a permission / prohibition of drain processing in the timing valve. A timing solenoid for switching prohibition, the control device for an automatic transmission, comprising: when the occurrence of idling is detected during shifting, the shift solenoid is returned to a state before the start of shifting, and the timing solenoid controls the shift solenoid. Drain processing in the timing valve is prohibited, and the accumulator back pressure of the release side frictional engagement element is On the other hand, when the convergence of the idling is detected, the shift solenoid is returned to a state corresponding to a shift request, and the timing solenoid permits drain processing in the timing valve, and releases the shift solenoid. The accumulator back pressure of the side friction engagement element is reduced stepwise.

According to this configuration, when the idling occurs during the shift, the hydraulic pressure of the release-side friction engagement element is increased in order to increase the torque capacity of the release-side friction engagement element. Since the hydraulic pressure is switched to the side where the hydraulic pressure is drained by the shift solenoid, the hydraulic pressure cannot be increased as it is. Therefore, the shift solenoid is returned to the state where the hydraulic pressure before the start of the shift is supplied, and
After ensuring the state in which the accumulator back pressure can be controlled by prohibiting drain processing in the timing valve, the accumulator back pressure of the disengagement-side friction engagement element is increased stepwise. Then, when the blowing is converged, the accumulator back pressure of the shift solenoid, the timing solenoid, and the disengagement side frictional engagement element is returned to the normal state.

According to the third aspect of the invention, the accumulator back pressure increase correction amount is determined in accordance with at least one of the engine speed and the temperature of the hydraulic oil.
According to this configuration, the correction amount when the accumulator back pressure of the disengagement side frictional engagement element is increased and corrected is adjusted to the engine rotational speed and / or the viscosity of the hydraulic oil correlated to the discharge amount of the oil pump driven by the engine. Determined according to the correlated oil temperature.

According to a fourth aspect of the present invention, the accumulator back pressure of the engagement-side frictional engagement element is controlled to the maximum hydraulic pressure for a predetermined period from the start of gear shifting, while the predetermined period is controlled by the engine rotational speed and the temperature of the hydraulic oil. Is determined in accordance with at least one of the above. According to such a configuration, the precharge control for controlling the accumulator back pressure of the engagement-side friction engagement element to the maximum hydraulic pressure only for a predetermined period from the start of the shift,
Filling the engagement side frictional engagement element with oil, and setting the period of the precharge control to an engine speed correlated with a discharge amount of an oil pump driven by the engine, and / or
Alternatively, it is determined according to the oil temperature correlated with the viscosity of the hydraulic oil.

According to the fifth aspect of the invention, the occurrence of idling is determined by comparing the input shaft rotation speed of the transmission mechanism with the reference input shaft rotation speed calculated from the output shaft rotation speed of the transmission mechanism and the gear ratio before shifting. The detection is performed according to the deviation. According to this configuration, from the output shaft rotation speed and the gear ratio before shifting,
The input shaft rotation speed when the gear ratio of the transmission mechanism maintains the gear ratio before the gear shift is calculated, and the calculated input shaft rotation speed (reference turbine rotation speed) is used as the actual input shaft rotation speed (turbine rotation speed). And when the actual input shaft rotation speed exceeds the reference input shaft rotation speed by a predetermined value or more, the occurrence of idling is detected.

According to the sixth aspect of the present invention, the convergence of the idling is determined by comparing the input shaft rotation speed of the transmission mechanism with the reference input shaft rotation speed calculated from the output shaft rotation speed of the transmission mechanism and the gear ratio before shifting. The detection is performed based on the differential value of the deviation. According to this configuration, whether the actual input shaft rotation speed is deviating from the reference input shaft rotation speed, which is the input shaft rotation speed when the gear ratio of the transmission mechanism maintains the gear ratio before the shift, or the reference input shaft rotation speed It is determined whether the actual input shaft rotation speed is approaching based on the differential value of the difference between the actual input shaft rotation speed and the reference input shaft rotation speed to detect the convergence of the airflow.

According to a seventh aspect of the present invention, the occurrence and convergence of the idling are detected based on a comparison between a gear ratio calculated from the input shaft rotation speed and the output shaft rotation speed of the transmission mechanism and a predetermined value. did. According to this configuration, the gear ratio is calculated from the input shaft rotation speed and the output shaft rotation speed of the transmission mechanism,
When the input shaft rotation speed increases with respect to the output shaft rotation speed and the gear ratio (gear ratio = input shaft rotation speed / output shaft rotation speed) exceeds a predetermined value, occurrence of idling is detected and the input shaft is detected. When the gear ratio becomes smaller than a predetermined value due to a decrease in the rotation speed, the convergence of the wind blow is detected.

[0017]

According to the first aspect of the present invention, when an idling occurs, the torque capacity of the disengagement side frictional engagement element is increased with good response, and the idling can be converged early. There is. According to the invention described in claim 2,
When an idling occurs, the torque capacity of the disengagement side frictional engagement element can be increased responsively and reliably to suppress the idling, while returning to the normal disengaging control state with the converging of the idling. In addition, it is possible to avoid an excessive correction of the torque capacity of the disengagement side frictional engagement element, and it is possible to stably suppress the occurrence of the idling without increasing the cost or extending the shift time.

According to the third aspect of the present invention, the control for increasing the back pressure of the accumulator is optimally controlled in accordance with the change in the discharge amount of the oil pump and the viscosity of the hydraulic oil, so that the torque capacity of the disengagement side frictional engagement element is controlled. Can be increased without excess or deficiency. According to the fourth aspect of the present invention, by pre-charging the oil to the engagement-side friction engagement element, it is possible to secure the responsiveness of the hydraulic pressure in the engagement-side friction engagement element, thereby more effectively reducing the occurrence of idling. This has the effect of being able to be suppressed in an effective manner.

According to the fifth aspect of the present invention, it is possible to detect the occurrence of idling with high accuracy and response even if the vehicle speed changes. According to the sixth aspect of the invention, there is an effect that the convergence of the idling can be detected with good response and high accuracy as a point in time at which the input shaft rotation speed switches to a tendency to approach the rotation speed before the shift.

According to the seventh aspect of the present invention, there is an effect that the occurrence and convergence of the idling can be easily detected regardless of a change in the vehicle speed.

[0021]

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 103 is connected to an output shaft of an engine 101 via a torque converter 102, and the output shaft of the automatic transmission 103 is shown in FIG. The driving wheels of the vehicle that do not rotate are driven.

The automatic transmission 103 includes a transmission mechanism 10
3A and a control valve section 103B. The control valve section 103B is controlled by an A / T controller 104. The A / T controller 104 incorporates a microcomputer, and includes an A / T oil temperature sensor 105, an accelerator opening sensor 106, a vehicle speed sensor 1
07, a turbine rotation sensor 108, an engine rotation sensor 109, an arithmetic processing of detection signals from the air flow meter 110, etc., to output a control signal to the control valve section 103B.

FIG. 2 is a skeleton showing the transmission mechanism 103A. The transmission mechanism 103A 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),
It is composed of 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 composed of 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.

The ring gear r1 of the planetary gear set G1 and the carrier c2 of the planetary gear set G2 are directly and integrally connected to the output shaft OUT. In the transmission mechanism 103A having the above configuration, the first to fourth speeds of forward movement and the reverse movement are realized by a combination of engagement states of the respective clutches and brakes, as shown in FIG.

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 & R at the first speed is used.
The fastening state indicated by the black circle of / B indicates fastening only in one range. As shown in the combination of the engagement states of the clutches and brakes shown in FIG.
When upshifting from third gear to third gear, the low clutch L /
While maintaining the fastening state of C, brake bands 2 & 4 /
At the same time when B is released, the high clutch H / C is engaged. As described above, a shift in which the engagement and disengagement of the clutch / brake (friction engagement element) is simultaneously controlled to switch the friction engagement element is referred to as a shift shift.

FIG. 4 shows the control valve section 103.
4 shows details of B. The control valve section 103B shown in FIG. 4 includes a shift valve (A) 1, a shift valve (B) 2, an accumulation control valve 3 for L / C & H / C, an accumulation control valve 4 for 2 & 4 / B, and L / C timing valve (A) 5 and L / C
Timing valve (B) 6, 2 & 4 / B timing valve (A) 7, 2 & 4 / B timing valve (B) 8
, L / C accumulator 9, 2 & 4 / B accumulator unit 10, and H / C accumulator unit 1.
1 is provided.

The shift valve (A) 1 and the shift valve (B) 2 are operated at the first speed through the OFF position of the shift solenoid (A) 21 and the shift solenoid (B) 22.
The oil passage is switched in accordance with the combination of the engagement and the release corresponding to each of the fourth speeds (OD). Specifically, as shown in FIG. 5, the ON / O of the shift solenoid (A) 21 and the shift solenoid (B) 22 is previously set for each gear position.
A combination of FFs is determined. For example, at the time of an upshift from the second speed to the third speed, the shift solenoid (A)
21 is continuously turned OFF, and the shift solenoid (B) 22 is switched from ON to OFF.

When the shift solenoid (A) 21 and the shift solenoid (B) 22 are OFF, the shift valves (A) 1 and (B) 2 have a pair of oil paths branched from one oil path. The lower side is selected, and conversely, when the shift solenoid (A) 21 and the shift solenoid (B) 22 are in the ON state, the upper side of the pair of oil passages is selected.

Therefore, at the time of the upshift from the second speed to the third speed, the hydraulic supply path to the brake band 2 & 4 / B is connected to the drain side (indicated by X in FIG. 4) while the low clutch L / The D range pressure PD supply side is connected to the hydraulic pressure supply paths of C and the high clutch H / C. L / C
& H / C accumulation control valve 3 is a solenoid pressure generated by PL duty solenoid 23.
The line pressure PL is reduced according to the size of PSOLA, and L / C
Accumulator 9 and H / C accumulator unit 1
Output the accumulation control pressure PACCMA for adjusting the back pressure of 1.

The solenoid pressure PSOLA generated by the PL duty solenoid 23 is a pressure modifier valve (P.MF.V) that regulates a modifier pressure which is a signal pressure of a line pressure PL generated by a pressure regulator valve (not shown). ). Accumulation control valve 4 for 2 & 4 / B
Is the line pressure P according to the magnitude of the solenoid pressure PSOLB generated by the 2 & 4 / B duty solenoid 24.
L is reduced, and the accumulator control pressure PACCMB for adjusting the back pressure of the 2 & 4 / B accumulator unit 10 is output.

The L / C timing valve (A) 5
L / C when the L / C timing solenoid 25 is OFF
This is a switching valve in which the signal pressure oil passage in the timing valve (B) 6 is set to the drain side, and when turned on, the signal pressure oil passage is set to the communication side. The L / C timing valve (B) 6 controls the operation of the L / C accumulator 9 when shifting up to the fourth speed or downshifting from the fourth speed, that is, at the time of shifting to release or engage the low clutch L / C. Perform back pressure control.

The 2 & 4 / B timing valve (A) 7
Is a switching valve that sets the signal pressure oil passage in the 2 & 4 / B timing valve (B) 8 to the drain side when the 2 & 4 / B timing solenoid 26 is OFF, and sets the signal pressure oil passage to the communication side when it is ON. The 2 & 4 / B timing valve (B) 8 is used when shifting up to third speed or shifting down from third speed, that is, when the brake band 2
The back pressure control of the 2 & 4 / B accumulator 10 is performed at the time of shifting for releasing or engaging & 4 / B.

In the L / C accumulator 9, the accumulator control pressure PACCMA is guided to the back pressure chamber via an L / C timing valve (B) 6, and the low clutch L / C is smoothly engaged and released. The 2 & 4 / B accumulator unit 10 has an accumulator control pressure PACC via a 2 & 4 / B timing valve (B) 8 in its back pressure chamber.
MB is guided to smooth the fastening and release of brake band 2 & 4 / B.

The 2 & 4 / B accumulator unit 10 incorporates a piston and a spring in a cylinder and sets the directions of the springs to be opposite to each other with respect to the back pressure to obtain two-stage accumulator characteristics having different shelf pressure levels. It is composed of two accumulators 10A and 10B. In the H / C accumulator unit 11, the accumulator control pressure PACCMA is directly guided to the back pressure chamber, and the engagement and release of the high clutch H / C are smoothed.

This H / C accumulator unit 11
Also, the piston and the spring are incorporated in the cylinder and the directions of the springs are set opposite to each other with respect to the back pressure, and are constituted by two accumulators 11A and 11B which obtain two-stage accumulator characteristics having different shelf pressure levels. here,
In the shift control for automatically shifting the first to fourth speeds in the D range, a shift command is issued in accordance with a shift schedule set in advance based on the throttle opening and the vehicle speed. In accordance with the ON / OFF command of the shift solenoid for each shift speed shown in FIG.
The control is performed by issuing an ON or OFF command to the shift solenoid (A) 21 and the shift solenoid (B) 22 from the / T control unit 20.

In the following, the operation at the time of shifting will be described by taking an example of an upshift from the second speed to the third speed. When the upshift from the second speed to the third speed is performed, the shift solenoid (A) 1 is continuously turned off. On the other hand, the shift solenoid (B) 22 is turned on.
, The D range pressure PD is continuously supplied to the low clutch L / C, while the hydraulic pressure supply path to the brake bands 2 & 4 / B is drained,
The D range pressure PD is supplied to the high clutch H / C which has been drained until then, and the brake band 2
& 4 / B and the high clutch H / C
Is switched to the fastened / disengaged state of the frictional engagement element,
An upshift from the third gear to the third gear is performed.

When the brake band 2 & 4 / B is released with an upshift from the second speed to the third speed, the back pressure of the 2 & 4 / B accumulator unit 10 is drained by the 2 & 4 / B timing valves 7 and 8. The timing at which it is performed is controlled. FIG.
As shown in the time chart of FIG. 5, during the upshift from the second speed to the third speed, the shift solenoid (A) 1 is kept OFF continuously while the shift solenoid (B) 22
Is switched from ON to OFF, and the 2 & 4 / B timing solenoid 26 is switched from OFF to ON.

2 & 4 / B timing solenoid 26 is O
In the case of FF, the signal pressure to the 2 & 4 / B timing valve (B) 8 is drained, and the 2 & 4 / B timing valve (B) 8 is biased leftward in FIG. Accumulator unit 1
The accum control pressure PACCMB is directly guided to the back pressure chamber 0, and the drain process by the 2 & 4 / B timing valve (B) 8 is prohibited.

On the other hand, 2 & 4 / B timing solenoid 2
When the valve 6 is turned on, the 2 & 4 / B timing valve (A) 7 switches the signal pressure oil passage from the drain side to the communication side, and changes the signal pressure oil passage on the fastening side as a signal pressure acting in the direction of draining the 2 & 4 / B accumulator back pressure. The high clutch pressure PHC is supplied so that the drain processing by the pressure balance can be performed.

On the other hand, a 2 & 4 / B timing valve (B)
In FIG. 8, the accumulator control pressure PACCMA on the fastening side is supplied as a signal pressure acting in the direction of supplying the 2 & 4 / B accumulator back pressure. As a result, the differential pressure ΔP between the accumulator control pressure PACCMA, which is the back pressure of the accumulator on the engagement side, and the high clutch pressure PHC, which is the operating pressure on the engagement side, becomes the set differential pressure (set by the spring load and the spool pressure receiving area). And 2 &
4 / B The spool of the timing valve (B) 8 is 2 & 4 /
The B accumulator back pressure is switched to the drain side.

When the spool of the 2 & 4 / B timing valve (B) 8 is switched to the side for draining the 2 & 4 / B accumulator back pressure, the D range pressure P is applied as a signal pressure acting in the direction of draining the 2 & 4 / B accumulator back pressure.
D is supplied, whereby the drain state of the 2 & 4 / B accumulator back pressure is maintained. The operating pressure of the high clutch H / C, which is the engagement side, increases after the stroke of the clutch piston ends, and with the increase of the operating pressure, the first clutch pressure characteristic by the piston stroke operation of the accumulator 11B is exhibited.
When the operation shifts to the second shelf pressure characteristic due to the piston stroke operation of A and the stroke operation by the accumulator 11A ends, the engagement pressure immediately increases to the line pressure level, and the high clutch H / C is engaged.

On the other hand, the brake bands 2 & 4 on the release side
/ B decreases from the engagement pressure based on the line pressure level to the accumulator back pressure level at once, and when the high clutch pressure PHC, which is the engagement side operating pressure, becomes the switching pressure of the 2 & 4 / B timing valve (B) 8, 2 & 4 / B. When the back pressure of the accumulator is drained, the brake band pressure P
24B drops at a large gradient to reach the release pressure level, releasing brake band 2 & 4 / B.

At the time of the release control, the solenoid pressure PSOLB previously generated by the 2 & 4 / B duty solenoid 24 is reduced from the maximum line pressure PL to the target solenoid pressure PSOLB corresponding to the input shaft torque at that time. After that, the shift solenoid (B) 22 is switched from ON to OFF to reduce the fastening pressure of the brake bands 2 & 4 / B to the accumulator back pressure level corresponding to the input shaft torque.

Similarly, when the low clutch L / C is disengaged and the brake band 2 & 4 / B is engaged, and the upshift from the third speed to the fourth speed is performed, the L / C timing valve (B) 6 operates in the same manner as described above. Drain timing control of the low clutch accumulator back pressure is performed. As described above, if the drain timing of the accumulator back pressure of the disengagement side frictional engagement element is controlled, it is possible to optimally control the drain timing regardless of the variation of the frictional engagement element and the hydraulic pressure fluctuation. In particular, during the first shift after the vehicle has been left for a long time, the oil in the clutch pack is completely drained and normal hydraulic response cannot be obtained, resulting in insufficient torque capacity at the time of changing gears, causing idling. There is.

Therefore, according to the present invention, the above-mentioned blowing is performed as shown in FIG.
In the following, the idling suppression control will be described with reference to the time chart of FIG. The flowchart of FIG. 7 is executed when an upshift from the second speed to the third speed is requested, and in step S1, the brake bands 2 & 4
/ B to release and engage the high clutch H / C,
Switch the shift solenoid (B) 22 from ON to OFF, and turn on the 2 & 4 / B timing solenoid 26
To

In step S2, it is determined whether or not an idling has occurred during the upshift from the second speed to the third speed by the above control. The determination of the occurrence of the idling is made based on a detection signal (output shaft rotation speed) of the vehicle speed sensor 107 that extracts a rotation signal from the output shaft of the automatic transmission and a gear ratio at the second speed before the shift, and a reference turbine rotation speed NtS ( The reference input shaft rotation speed) is calculated, and the actual turbine rotation speed Nt (input shaft rotation speed) detected by the turbine rotation sensor 108 is calculated as follows:
When it becomes higher than the reference turbine rotation speed Nts + predetermined value HYS (1) (Nt> NtsS + HYS (1)),
Detects the occurrence of air blowing.

Further, a gear ratio (gear ratio = input shaft rotation speed / output) is obtained from a detection signal (output shaft rotation speed) of the vehicle speed sensor 107 and a turbine rotation speed Nt (input shaft rotation speed) detected by the turbine rotation sensor 108. (Shaft rotation speed) is calculated, and when the gear ratio becomes larger than a reference gear ratio (1) set based on the gear ratio in the second speed before the shift, the occurrence of idling is detected. May be.

When the occurrence of the idling is detected in step S2, the process proceeds to step S3, in which the 2 & 4 / B timing solenoid 26 is turned off, and the release side 2 & 4 /
The B accumulator back pressure is prevented from being drained by the action of the 2 & 4 / B timing valve (B) 8. Also,
In step S4, the control duty of the 2 & 4 / B duty solenoid 24 is corrected in order to increase the 2 & 4 / B accumulator back pressure. Specifically, the base duty corresponding to the input shaft torque is corrected by a predetermined correction amount, and the correction amount is set according to the engine speed and the oil temperature as shown in FIG. The correction amount increases as the engine speed decreases and the oil temperature decreases.

In this embodiment, the oil pump for supplying the hydraulic oil is driven by the engine, and the lower the engine speed, the smaller the discharge amount of the oil pump.
The lower the engine speed, the greater the correction amount,
The torque capacity on the release side is rapidly increased. In addition, when the temperature of the hydraulic oil is low, the hydraulic response is slow. Therefore, the correction amount is increased as the oil temperature is low, so that the torque capacity on the release side is quickly increased.

In step S5, brake bands 2 & 4
/ B hydraulic pressure supply path is drained from D range pressure P
OFF according to an upshift request from 2nd gear to 3rd gear to return to the state where D is supplied, that is, the state at 2nd gear
The shift solenoid (B) 22 is turned ON.
As described above, the 2 & 4 / B accumulator back pressure is increased, and the shift solenoid (B) 22 is turned on to release the D range pressure PD to the brake band 2 & 4 / B, thereby releasing the brake band. By increasing the fastening pressure (torque capacity) of the brake bands 2 & 4 / B on the side, the idling state due to insufficient torque capacity is eliminated.

It is to be noted that the amount of oil discharged from the clutch pack of the brake band 2 & 4 / B can be limited to some extent only by increasing the back pressure of the 2 & 4 / B accumulator, but it is insufficient for the early convergence of the idling. Therefore, the shift solenoid (B) 22 is turned ON to switch the brake band 2
D range pressure PD is supplied to the & 4 / B clutch pack.

In step S6, it is determined whether or not the blowing has converged. The convergence of the wind blow is determined when the differential value of the difference between the turbine rotation speed Nt and the reference turbine rotation speed Nts becomes smaller than a predetermined value HYS (2) (for example, 0) (d / dt (Nt-NtS). ) <HYS
(2)) It is possible to adopt a configuration for detecting the convergence of the blowing. According to this, when the turbine rotation speed Nt changes from a tendency to depart from the reference turbine rotation speed NtS to a tendency to return toward the reference turbine rotation speed NtS, it is possible to detect the convergence of the air blowing.

The detection signal of the vehicle speed sensor 107 and the turbine rotation speed N detected by the turbine rotation sensor 108
The gear ratio (gear ratio = input shaft rotation speed / output shaft rotation speed) is calculated from t and the gear ratio is larger than the reference gear ratio (2) set based on the gear ratio in the second speed before the gear shift. When it becomes smaller, the convergence of the blowing may be detected.

If the convergence of the blowing is detected based on the differential value of the difference between the turbine speed Nt and the reference turbine speed NtS, the time when the blowing is reversed to the convergence tendency is detected with good response. Thus, it is preferable to a configuration in which it is possible to converge the air blow in a short time while avoiding excessive correction, and to detect the convergence of the air blow based on the gear ratio.

When the convergence of the blowing is detected in step S6, the processes in steps S7 to S9 are performed in order to return to the normal shift control state from the second speed to the third speed. In step S7, the 2 & 4 / B accumulator back pressure on the release side is turned on by turning on the 2 & 4 / B timing solenoid 26.
The 2 & 4 / B timing valve (B) 8 is made to be drained.

In step S8, the control for increasing the 2 & 4 / B accumulator back pressure is stopped, and the 2 & 4 / B accumulator back pressure is returned to the base value. In step S9, the shift solenoid (B) 22 is turned off to return to the third speed state in which the hydraulic supply path of the brake bands 2 & 4 / B is drained. When the occurrence of the idling is detected as described above, the shift solenoid is returned to the original control state at the second speed, and
If the & 4 / B accumulator back pressure is increased, the fastening pressure (torque capacity) of the brake band 2 & 4 / B can be increased in a responsive manner, and the idling can be converged in a short time.
In addition, the correction amount for increasing the back pressure of the 2 & 4 / B accumulator is
The engine speed, which correlates to the oil pump output,
By setting according to the oil temperature indicating the viscosity of the hydraulic oil, the brake band 2 & 4 /
The fastening pressure (torque capacity) of B can be increased enough to converge the idling.

Since the occurrence of idling is presumed to be caused by a delay in the hydraulic response on the engagement side, precharging is performed on the high clutch H / C on the engagement side by controlling the back pressure. The precharge control will be described with reference to the flowchart of FIG. In the flowchart of FIG.
Then, it is determined whether or not the upshift from the 2nd speed to the 3rd speed is started, and when the upshift from the 2nd speed to the 3rd speed is started, the process proceeds to step S12.

In step S12, a precharge time TIM1 is set according to the engine speed and the oil temperature.
As shown in FIG. 10, the precharge time TIM1 is set to be longer as the engine speed is lower and the oil temperature is lower. This is because, similarly to the setting characteristic of the correction amount, the lower the engine speed, the smaller the discharge amount of the oil pump, and the lower the temperature of the hydraulic oil, the lower the hydraulic response.

In step S13, a timer for measuring an elapsed time from the start of the upshift from the second speed to the third speed is counted up. In step S14, the time measured by the timer is shorter than the precharge time TIM1. It is determined whether or not. If the time measured by the timer is shorter than the precharge time TIM1, the process proceeds to step S15, and the precharge for the high clutch H / C on the engagement side is executed.

The precharge is performed by increasing the back pressure of the H / C accumulator to the maximum pressure.
By controlling the PL duty solenoid 23, the accumulation control pressure PACCMA is set to the line pressure which is the maximum pressure. Then, the precharge which sets the H / C accumulator back pressure to the maximum pressure is performed by the precharge time T.
If only IM1 is continued, steps S14 to S
Proceeding to 16, the precharge is stopped, and the H / C accumulator back pressure is returned to a value corresponding to the input shaft torque.

In the above-described embodiment, when an idling occurs during the upshift from the second gear to the third gear, the torque capacity is increased by the back pressure correction control only on the brake band 2 & 4 / B, which is the release side, and the idle capacity is increased. Although the convergence of the blow is configured, the back pressure on the high clutch H / C side, which is the engagement side, may be corrected and controlled at the same time. Specifically, 2 &
In the section where the 4 / B accumulator back pressure is increased,
The H / C accumulator back pressure only needs to be increased by controlling the PL duty solenoid 23, and the increase correction amount of the H / C accumulator back pressure is similar to the case where the 2 & 4 / B accumulator back pressure is increased. What is necessary is just to set from oil temperature.

[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 hydraulic circuit diagram showing a control valve unit in the embodiment.

FIG. 5 is a diagram showing a combination of ON / OFF of shift solenoids A and B at each shift speed in the embodiment.

FIG. 6 is a time chart showing control at the time of a second-speed to third-speed upshift in the embodiment.

FIG. 7 is a flowchart showing release-side control during a second-speed to third-speed upshift in the embodiment.

FIG. 8 is a diagram showing characteristics of a correction amount of a back pressure control amount in the embodiment.

FIG. 9 is a flowchart showing engagement-side precharge control during a second-speed to third-speed upshift in the embodiment.

FIG. 10 is a diagram showing characteristics of a precharge time in the precharge control.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Shift solenoid (A) 2 ... Shift solenoid (B) 3 ... Accum control valve for L / C & H / C 4 ... Accum control valve for 2 & 4 / B 5 ... L / C timing valve (A) 6 ... L / C timing Valve (B) 7 ... 2 & 4 / B timing valve (A) 8 ... 2 & 4 / B timing valve (B) 9 ... L / C accumulator 10 ... 2 & 4 / B accumulator unit 11 ... H / C accumulator unit 21 ... Shift solenoid (A) 22: shift solenoid (B) 23: PL duty solenoid 24: 2 & 4 / B duty solenoid 25: L / C timing solenoid 26: 2 & 4 / B timing solenoid 101: engine 102: torque converter 103: automatic transmission 103A: transmission mechanism Part 103B ... Troll valve unit 104: A / T controller 105: A / T oil temperature sensor 106: accelerator opening sensor 107: vehicle speed sensor 108: turbine rotation sensor 109: engine rotation sensor 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 & reverse brake L / OWC ... one-way clutch

Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat II (reference) F16H 63:12 F16H 63:12 F term (reference) 3J552 MA02 MA12 NA01 NB01 PA24 QA04C QA26C QA34C QA48C RA13 RC09 RC15 SA07 SA08 TB03 TB07 VA07W VA32W VA37W VA48W VA50Z VA52W VA53Z VA74W VA76W VA77Z VA78W VB01Z VC01W VC05Z VD02Z

Claims (7)

[Claims] An automatic transmission configured to perform a shift by changing a friction engagement element that simultaneously performs engagement control and release control of two different friction engagement elements while controlling a back pressure of an accumulator. The automatic transmission according to claim 1, further comprising: supplying hydraulic pressure to the disengagement-side friction engagement element and increasing and correcting the accumulator back pressure of the disengagement-side friction engagement element when an idling is detected during the shift. Machine control device. 2. A control device for an automatic transmission configured to perform a shift by changing a friction engagement element that simultaneously performs engagement control and release control of two different friction engagement elements, wherein each friction engagement element includes: A shift solenoid that switches on and off the supply and discharge of oil to and from the element, a duty solenoid that controls a back pressure of an accumulator interposed in an oil supply path to each friction engagement element, and a engagement-side friction engagement element Automatic transmission having a timing valve for determining the timing of draining the accumulator back pressure of the disengagement side frictional engagement element in accordance with the rise of the operating pressure of the valve, and a timing solenoid for switching permission / prohibition of drain processing in the timing valve. In the control device of the engine, when the occurrence of idling is detected during the shift, the shift solenoid is returned to a state before the start of the shift, and The timing solenoid prohibits drain processing in the timing valve and raises the accumulator back pressure of the disengagement side frictional engagement element in a stepwise manner, while shifting the shift solenoid when the convergence of idling is detected. An automatic transmission characterized by returning to a state according to a request, permitting the drain processing in the timing valve by the timing solenoid, and reducing the accumulator back pressure of the disengagement side frictional engagement element in a stepwise manner. Machine control device. 3. The accumulator back pressure increase correction amount is:
3. The control device for an automatic transmission according to claim 1, wherein the control device determines the rotational speed based on at least one of an engine rotational speed and a temperature of hydraulic oil. 4. A structure in which the accumulator back pressure of the engagement-side frictional engagement element is controlled to the maximum hydraulic pressure for a predetermined period from the start of the shift, and the predetermined period is determined according to at least one of the engine speed and the temperature of the hydraulic oil. The control device for an automatic transmission according to any one of claims 1 to 3, wherein the control device is determined. 5. The occurrence of the idling is detected in accordance with a deviation between an input shaft rotation speed of a transmission mechanism and a reference input shaft rotation speed calculated from an output shaft rotation speed of the transmission mechanism and a gear ratio before shifting. The control device for an automatic transmission according to any one of claims 1 to 4, wherein: 6. The method according to claim 6, wherein the convergence of the idling is calculated as a differential value of a deviation between an input shaft rotation speed of the transmission mechanism and a reference input shaft rotation speed calculated from an output shaft rotation speed of the transmission mechanism and a gear ratio before shifting. The control apparatus for an automatic transmission according to any one of claims 1 to 5, wherein the detection is performed based on the control information. 7. The method according to claim 1, wherein the occurrence and convergence of the idling are detected based on a comparison between a gear ratio calculated from an input shaft rotation speed and an output shaft rotation speed of a transmission mechanism and a predetermined value. The control device for an automatic transmission according to any one of claims 1 to 4.