JP3475481B2 - Hydraulic 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 hydraulic control system for an automatic transmission, and more particularly to reducing shift shock of the automatic transmission.

[0002]

2. Description of the Related Art Conventionally, as a prior art document related to a hydraulic control device for an automatic transmission, one disclosed in Japanese Patent Application Laid-Open No. 2-203068 is known.

The schematic construction of one system of the hydraulic control system in this system is represented by a block diagram as shown in FIG. In FIG. 12, the electric signal path is shown by a broken line, and the hydraulic path is shown by a solid line.

In FIG. 12, 1 is an oil pump, 2 is a pressure regulating valve, and the hydraulic path from the oil pump 1 is connected to the IN side of the pressure regulating valve 2. 3 is an ECU (Electronic
A control unit: an electronic control unit), and a signal indicating a physical quantity such as a throttle opening, a vehicle speed, a turbine speed of an automatic transmission, etc., which is changed according to an operating state of an internal combustion engine, is input to the ECU 3. 4 is an ON / OFF solenoid, and the IN side of the ON / OFF solenoid 4 is the O of the pressure regulating valve 2.
It is connected to the hydraulic path from the UT side. This ON / O
A control signal from the ECU 3 is input to the FF solenoid 4. Further, 5 is an accumulator, and the IN side of the accumulator 5 is the OUT of the ON / OFF solenoid 4.
It is connected to the hydraulic path from the side. Further, 6 is an electromagnetic pressure regulating valve, and the IN side of the electromagnetic pressure regulating valve 6 is the OUT of the pressure regulating valve 2.
The hydraulic path from the ON / OFF solenoid 4 from the side is connected to another hydraulic path. The hydraulic path from the OUT side of the electromagnetic pressure regulating valve 6 is connected to the back pressure side of the accumulator 5. A control signal from the ECU is input to the electromagnetic pressure regulating valve 6. Furthermore, 7 is a clutch that constitutes a friction element, and is connected to a hydraulic path from the OUT side of the accumulator 5.

The oil discharged from the oil pump 1 is adjusted to the line oil pressure PL by the pressure adjusting valve 2. Here, the ECU 3 based on physical quantities such as the throttle opening, the vehicle speed, and the turbine speed of the automatic transmission, which changes in accordance with the operating state of the internal combustion engine.
ON / OFF solenoid 4 is selectively opened /
It is closed. ON / OFF by signal from ECU3
When the solenoid 4 is turned on, the pressure is regulated by the pressure regulating valve 2
One line hydraulic pressure PL1 of the system passes through the ON / OFF solenoid 4 and is applied to the IN side of the accumulator 5 as a clutch hydraulic pressure PC. Further, the electromagnetic pressure regulating valve 6 is operated by the signal SLA from the ECU 3. Then, the other line hydraulic pressure P of the two systems regulated by the pressure regulating valve 2
L2 passes through the electromagnetic pressure regulating valve 6 to be a predetermined hydraulic pressure Pa, which is applied to the back pressure side of the accumulator 5. The accumulator 5 utilizes the pressure applied to the back pressure side (predetermined hydraulic pressure Pa) and the elastic action of a built-in spring or the like to increase the clutch hydraulic pressure PC 'to the OUT side clutch 7 against the pressure increase on the IN side. It is intended to moderate the increase in pressure. As a result, the clutch hydraulic pressure PC '[kg f / cm ² ] is shown in FIG.
As shown in the time chart for increasing the pressure, it is possible to control the pressure increase within a predetermined control range.

[0006]

By the way, in the above-mentioned one, the accumulator is used in order to prevent the sudden increase in the hydraulic pressure and to reduce the shift shock when the clutch hydraulic pressure rises. However, the pressure applied to the back pressure side of the accumulator is controlled. It is impossible to accurately set the predetermined clutch hydraulic pressure and to widen the hydraulic control range by only using this, and there was a limit to the reduction of shift shock.

Therefore, the present invention has been made in order to solve such a problem, and by making the shift time for engaging the clutch variable, the shift shock generated against the driver's intention is further reduced. An object of the present invention is to provide a hydraulic control device for an automatic transmission that can perform the above.

[0008]

According to a first aspect of the present invention, there is provided a hydraulic control device for an automatic transmission, which includes a detecting means for detecting a changing speed of a physical quantity which changes in accordance with an operating state of an internal combustion engine, and a gear having a plurality of gears. Coupling state control means for controlling the coupling state by directly electronically controlling the operating pressure of the friction element arranged between the rows, and the initial value of the control signal based on the changing speed detected by the detecting means Is set, and the shift speed when shifting down
Is lower than the final turbine speed at
In After reaching the turbine rotational speed, the fluctuation time of the control signal for controlling the working pressure by the coupling state control means
The changing speed detected by the detecting means instead of the initial value
And a working pressure control means for appropriately changing the correction value based on the above.

According to a second aspect of the present invention, in addition to the means provided in the first aspect, the hydraulic pressure control device for an automatic transmission is characterized in that the change speed detected by the detecting means at the time of shift-up is changed by the operating pressure control means. The slower the time, the longer the fluctuation time of the operating pressure.

[0010]

According to the present invention, the physical quantity changing according to the operating state of the internal combustion engine is detected by the detecting means, and the operating pressure control means sets the initial value of the control signal based on the changing speed.
The operating pressure is controlled directly and electronically by the coupling state control means for controlling the coupling state of the friction elements arranged between the gear trains of the plurality of shift speeds, and the maximum operation at the shift speed during downshifting is performed.
Turbine rotation lower than the final turbine speed by a specified value
After reaching the number, the operating pressure depends on the initial value of the control signal.
Based on the correction value based on the change speed detected by the detection means
The operating pressure is taken as the operating pressure, and the fluctuation time of the operating pressure just before the end of the shift is extended.
It is changed as appropriate. Therefore, the required fluctuation of the operating pressure can be obtained according to the operating state.

In addition to the operation of claim 1 , the operating pressure control means of the hydraulic control device for an automatic transmission according to claim 2 has a variation time of the operating pressure as the changing speed detected by the detecting means at the time of shift-up is slower. Is lengthened and the coupling of the friction elements is slowly controlled.

[0012]

EXAMPLES The present invention will be described below based on specific examples.

FIG. 1 is a block diagram showing a schematic structure of one system of a hydraulic control system in a hydraulic control system for an automatic transmission according to one embodiment of the present invention, in which electric signal paths are indicated by broken lines and each hydraulic path is indicated by solid lines. Are shown respectively. It should be noted that the same reference numerals and symbols are given to those having the same configuration or corresponding portions as those of the above-described conventional apparatus.

In FIG. 1, 1 is an oil pump, 2 is a pressure regulating valve, and the hydraulic path from the oil pump 1 is a pressure regulating valve 2.
Is connected to the IN side of. 3 is an ECU, and the ECU
Signals such as a throttle opening, a vehicle speed, and a turbine speed of the automatic transmission, which are physical quantities that change in accordance with the operating state of the internal combustion engine, are input to 3. Further, 6 is an electromagnetic pressure regulating valve, and the IN side of the electromagnetic pressure regulating valve 6 is connected to a hydraulic path from the OUT side of the pressure regulating valve 2. Then, the control signal SC from the ECU 3 is input to the electromagnetic pressure regulating valve 6. Furthermore,
Reference numeral 7 is a clutch that constitutes a friction element, and is an electromagnetic pressure regulating valve 6
The hydraulic path from the OUT side of is connected.

The oil discharged from the oil pump 1 is adjusted to the line oil pressure PL by the pressure adjusting valve 2. The line oil pressure PL regulated by the pressure regulating valve 2 is applied to the IN side of the electromagnetic pressure regulating valve 6. A control signal S calculated by the ECU 3 based on signals such as throttle opening, vehicle speed and turbine speed of the automatic transmission.
C is input to the electromagnetic pressure regulating valve 6. And the electromagnetic pressure regulating valve 6
Is controlled by the control signal SC, the line hydraulic pressure PL applied from the pressure regulating valve 2 side to the IN side of the electromagnetic pressure regulating valve 6 becomes the clutch hydraulic pressure PC applied to the clutch 7 from the OUT side of the electromagnetic pressure regulating valve 6. It is regulated.

FIG. 4 is a time chart showing a situation in which a shift judgment at the time of upshift occurs in the hydraulic control device for an automatic transmission according to one embodiment of the present invention. The solid line indicates the behavior of the throttle opening TA when the changing speed of the throttle opening is fast, and the broken line indicates the behavior when the changing speed of the throttle opening TA is slow.

In FIG. 4, a shift determination (in this embodiment,
When the shift up from 2nd to 3rd) is performed at time t1, based on the map shown in FIG. 5, the electromagnetic pressure regulating valve 6 for the throttle opening change speed which is the inclination component (differential value) of the throttle opening TA at time t1 Initial value F of control signal SC of
The DUT is set. That is, the initial value FD of the control signal SC
UT is set to be small when the absolute value of the inclination of the throttle opening TA is steep, and is set to be large when the absolute value of the inclination of the throttle opening TA is gentle. Then, the clutch hydraulic pressure PC is F / B controlled so that the time from the time t2 or t3 at which the change of the turbine speed NT starts to the end of the change becomes the target shift time TH. That is, based on the map shown in FIG. 6, the target shift time TH of the turbine speed NT with respect to the throttle opening change speed at time t1 is set. That is, the target shift time TH of the turbine speed NT is
When the absolute value of the inclination of the throttle opening TA is steep, it is set small, and when the absolute value of the inclination of the throttle opening TA is gentle, it is set large. Here, the relationship between the duty ratio of the control signal SC of the electromagnetic pressure regulating valve 6 and the clutch hydraulic pressure PC is shown in FIG.
As shown in the characteristic diagram in Fig. 1, the clutch oil pressure PC is high in the vicinity of the duty ratio of the control signal SC being 0, and the control signal S
When the duty ratio of C exceeds a certain value, the clutch hydraulic pressure PC gradually decreases in inverse proportion to the increase of the control signal SC, and the characteristic that the clutch hydraulic pressure PC becomes 0 when the duty ratio of the control signal SC is 100%. Have

In this way, the clutch hydraulic pressure PC is directly controlled electronically by the signal from the ECU 3 by the electromagnetic pressure regulating valve 6, so that the clutch hydraulic pressure PC [kg f /
As for the control range of [cm ² ], as shown in FIG. 8, the clutch hydraulic pressure PC can be controlled gently from the lower range side compared to the conventional control range (the control range shown in the time chart of FIG. 13). Since the hydraulic control range can be expanded, the shift time for hydraulic control can be extended.

FIG. 9 is a time chart showing a situation in the hydraulic control device for an automatic transmission according to one embodiment of the present invention when a gear shift judgment is made at the time of kick down and shift down. When the throttle opening TA changes to the open side due to a sudden depression and downshifting is performed, that is,
The behavior during kickdown is shown by the solid line, and the throttle opening T
A broken line shows the behavior during normal downshift when A gradually changes to the closing side.

In FIG. 9, the shift determination (in this embodiment,
When the kickdown from the 3rd to the 2nd or the normal downshift is performed at time t11, the throttle opening change speed that is the inclination component (differential value) of the throttle opening TA at time t11 based on the map shown in FIG. The initial value FDUT of the control signal SC of the electromagnetic pressure regulating valve 6 for is set. That is, the initial value FDUT of the control signal SC is set to be large when the absolute value of the inclination of the throttle opening TA is steep and small when the absolute value of the inclination of the throttle opening TA is gentle. Then, the clutch hydraulic pressure PC is controlled from time t12 or time t14 when the change of the turbine speed NT starts.

Here, in a normal downshift,
At time t15 when the difference between the turbine speed NT in the middle of the change and the final speed becomes equal to or less than a preset predetermined value,
A correction value for the throttle opening change speed at time t11 is set on the basis of the map shown in FIG. 11, and the control signal SC of the electromagnetic pressure regulating valve 6 is changed from the initial value FDUT to a smaller correction value. Therefore, the decrease of the clutch hydraulic pressure PC is delayed by the amount of the change, and the shift shock at the time of downshifting is reduced.

Next, the processing procedure at the time of upshift of the ECU 3 used in the hydraulic control system for the automatic transmission according to the embodiment of the present invention will be described with reference to the flow charts of FIGS. This will be described with reference to the time chart and FIGS. 5 and 6.

<< Electromagnetic Pressure Regulator Control Main Routine: See FIG. 2 >> In step S101, the vehicle speed and throttle opening at that time are read, and whether or not there is a shift determination based on a map (not shown) stored in advance To be judged. Step S10
If there is a shift determination (time t1 in FIG. 4) in step 1, the process proceeds to step S102, and the throttle opening change amount ΔT, which is the difference between the read previous value and the current value of the throttle opening.
A is calculated. Next, in step S103, the initial value FDUT of the control signal SC of the electromagnetic pressure regulating valve 6 for the throttle opening change speed based on the throttle opening change amount ΔTA is set based on the map shown in FIG. Next, the process proceeds to step S104, the target shift time TH for the throttle opening change speed is set based on the map shown in FIG. 6, and the process proceeds to step S105. On the other hand, step S
If there is no shift determination in 101, step S102.
~ Step S104 is skipped and Step S10 is performed.
Go to 5. In step S105, it is determined whether or not gear shifting is in progress. If gear shifting is not in progress, this program ends.

On the other hand, if gear shifting is in progress in step S105, the process proceeds to step S106 and F / B (feedback) is performed.
It is determined whether it is during the period. In this hydraulic pressure F / B control period,
Feedback control is performed by the control signal SC of the electromagnetic pressure regulating valve 6, that is, the turbine speed NT at which the clutch hydraulic pressure PC is read so that the target shift time TH of the turbine speed NT shown in FIG. 6 is achieved. In step S106, it is determined whether or not the F / B period is in progress. If the gear change is in progress and the F / B period is not in progress, the process proceeds to step S107, and the initial value FDUT calculated from the map of FIG. 5 is set to the control value SC. Then, the process proceeds to step S112.

On the other hand, when the F / B period is in progress in step S106, the process proceeds to step S108, and the first time,
That is, it is determined whether the F / B control has just started. When the determination in step S108 is established, step S10
9, the turbine rotation speed change amount DNT is calculated by multiplying the output rotation speed NO by the gear ratio iA after shifting and subtracting from the current turbine rotation speed NT. Next, the process proceeds to step S110, and the target turbine rotation speed change TDNT is calculated by dividing the turbine rotation speed change amount DNT calculated in step S109 by the target shift time TH.
When the determination in step S108 is not established,
The processes of steps S109 and S110 are skipped. Next, the process proceeds to step S111, and the turbine rotation speed change amount DNT calculated in step S109 is changed to the target turbine rotation speed change T calculated in step S110.
After PID control which will be described later to be DNT, the process proceeds to step S112, and the control value SC after the PID control is performed.
Is output and this routine ends.

<PID Control Subroutine: See FIG. 3> Next, the PID control subroutine of step S111 described above will be described.

In step S201, the current turbine revolution speed change amount NDNT is calculated by subtracting the previous turbine revolution speed NTOLD from the present turbine revolution speed NTNEW.
Next, the process proceeds to step S202, and the current deviation E
RRNEW is calculated by subtracting the target turbine rotation speed change rate TDNT calculated in step S110 from the turbine rotation speed change amount NDNT calculated in step S201. Next, the process proceeds to step S203 and step S20.
Each correction term of PID control for the deviation ERRNEW calculated in 2 (ΔP: proportional term, ΔI: integral term, ΔD: derivative term)
Is calculated by the following equations (1) to (3).

ΔP = KP × ERRNEW (1) ΔI = KI × ∫ERRNEW dt (2) ΔD = KD × (ERRNEW-ERROLD) (3) where KP, KI, and KD are It is the gain for calculating each correction term, and ERROLD is the previous deviation. Based on these correction terms, the control correction amount ΔSC is calculated by the following equation (4).

ΔSC = ΔP + ΔI + ΔD (4) Next, the process proceeds to step S204, where the present turbine rotation speed NTNEW is the previous turbine rotation speed NTOLD, the current deviation ERRNEW is the previous deviation ERROLD, and the current control is also After the value SC is stored as the previous control value SCOLD, the process proceeds to step S205. Step S20
In 5, the control value SC is calculated by adding the control correction amount ΔSC calculated in step S203 to the previous control value SCOLD.

By executing the above-described control, as shown in FIG. 4, when the speed of change of the throttle opening TA is large, that is, when the speed at which the driver depresses the accelerator pedal is high, the target shift time is from the time t1. It is as short as time t4, and when the driver depresses the accelerator pedal slowly, the target shift time is lengthened from time t1 to time t5. Therefore, at the time of upshifting, the shift shock is reduced as the driver demands a smoother driving state.

Here, when it is determined in the shift determination in step S101 that it is during kickdown, the routine is withdrawn from this routine and t11 of the time chart shown in FIG.
From the beginning of the time point, the duty ratio of the control signal SC of the electromagnetic pressure regulating valve 6 is set to 100%, and the clutch hydraulic pressure PC is controlled as quickly as possible. That is, in this case, the driver anticipates the occurrence of a shift shock, the shift time is reduced as much as possible, the clutch 7 is connected, and the agile shift is performed while preparing for the shift shock. is there.

When it is determined in the shift determination in step S101 that the shift is down, the routine is withdrawn from this routine, and from the beginning of time t11 in the time chart shown in FIG. 9, from the map of FIG. 10 by another routine not shown. The initial value FDUT of the control signal SC of the electromagnetic pressure regulating valve 6 is calculated and used as the control signal SC of the electromagnetic pressure regulating valve 6. Then, it is determined whether or not the turbine speed has reached a turbine speed lower by a predetermined value than the final turbine speed in the shift stage at the time of downshifting, and after this arrival, a correction value is calculated from the map of FIG. Control signal S for electromagnetic pressure regulating valve 6
C Therefore, the shift time is slightly lengthened, and the shift shock that occurs when the clutch 7 is finally engaged is reduced by extending the falling time of the clutch hydraulic pressure PC by the correction value of the control signal SC of the electromagnetic pressure regulating valve 6.

As described above, the hydraulic control system for the automatic transmission according to the present embodiment detects the change speed of the throttle opening TA in the physical quantity that changes according to the operating state of the internal combustion engine.
The engagement state can be controlled by directly electronically controlling the operating pressure, which is the clutch hydraulic pressure PC of the friction element composed of the detecting means achieved by U3 and the clutch 7 arranged between the gear trains of the plurality of shift stages. Based on the changing speed detected by the detecting means and the connection state control means including the electromagnetic pressure regulating valve 6
Set the initial value FDUT of the control signal SC and shift down
For the final turbine speed NT at the gear
After reaching the turbine rotational speed NT lower by a fixed value, the clutch hydraulic pressure PC is controlled by the engagement state control means.
EC instead of the initial value FDUT for the fluctuation time of the control signal SC
Operation of the internal combustion engine detected by the detection means achieved in U3
Of the physical quantities that change depending on the rolling state, the throttle opening T
And an operating pressure control means achieved by the ECU 3 that appropriately changes the correction value based on the changing speed of A.
This can be the embodiment of claim 1.

Therefore, the throttle opening TA is determined by the ECU
Is detected by the detection means is achieved by 3, in operation pressure control means is accomplished by ECU3 on the basis of the change rate, E
The initial value FDUT of the control signal SC from the CU3 is set.
Accordingly, the clutch hydraulic pressure PC by the engagement state control means including the electromagnetic pressure regulating valve 6 for controlling the engagement state of the friction element including the clutch 7 arranged between the gear trains of the plurality of shift stages is directly
Electronically controlled by a control signal SC from the ECU 3, Schiff
For the final turbine speed NT at the gear position during downshift
After reaching the turbine speed NT lower by a predetermined value,
Is the clutch hydraulic pressure according to the initial value FDUT of the control signal SC
Changes in the throttle opening TA detected by the detection means from PC
The clutch hydraulic pressure PC is based on the correction value based on the
Variation time of the clutch oil pressure PC is changed as appropriate.

Therefore, the required fluctuation of the operating pressure can be obtained according to the operating state , that is, the operating state is opposite to the initial operating pressure.
By being displayed, it is possible to change the fluctuation time of the operating pressure after that.
It is possible to reduce the shift shock that satisfies the requirements in the end.
End , that is, the end of shifting that greatly affects the occurrence of shifting shock
The fluctuation time of the operating pressure just before is extended, and the shift shock is appropriately reduced.

The operating pressure control means achieved by the ECU 3 of the hydraulic control system for the automatic transmission according to the present embodiment is the operating state of the internal combustion engine detected by the detection means achieved by the ECU 3 during upshifting. slower the rate of change of the throttle opening degree TA of the physical quantity that changes in accordance with the clutch
It is intended to increase the variation time of the oil pressure PC, according to this
The example of item 2 can be used.

[0037] Therefore, the variation time of the detected Slower rate of change of the throttle opening degree TA clutch oil pressure PC by the detection means at the time of shift-up is prolonged.

Therefore, the shift shock reduction ratio is increased as the smoother driving condition is required, and the drivability is improved.

By the way, in the above-described embodiment, the throttle opening T is set as the physical quantity that changes in accordance with the operating state of the internal combustion engine.
Although the clutch oil pressure PC is controlled based on the throttle opening change speed, which is the change speed of A, the same control is performed by using the change speed of the intake air amount, the engine speed, etc. as the physical quantity. , The same action and effect can be obtained.

[0040]

As described above, according to the hydraulic control system for an automatic transmission of the first aspect, the physical quantity that changes in accordance with the operating state of the internal combustion engine is detected by the detecting means, and based on the changing speed thereof. The operating pressure control means sets the initial value of the control signal.
The operating pressure is controlled electronically directly by the coupling state control means for controlling the coupling state of the friction elements arranged between the gear trains of a plurality of shift speeds, and the operating pressure control means shifts down.
Predetermined value for the final turbine speed at the gear
After reaching a low turbine speed, the initial control signal
Based on the speed of change detected by the detection means from the operating pressure
Based on the correction value, the operating pressure is changed, and the fluctuation time of the operating pressure is appropriately changed. As a result, the change in the operating pressure required according to the driving state, that is, the shift time is set by reflecting the driver's intention , that is, the driving state is the initial operation.
By being reflected in the pressure, the change in the operating pressure fluctuation time
And the reduction of shift shock that is finally required.
Satisfaction, i.e., the fluctuation time of the working pressure just before the end of the shift is extended
As a result, shift shock is reduced.

According to the hydraulic control device for an automatic transmission of claim 2 , in addition to the effect of claim 1 , the slower the changing speed detected by the detecting means at the time of shift-up by the operating pressure control means, the lower the operating pressure. The fluctuation time is lengthened and the coupling state of the friction elements is controlled slowly. As a result, the reduction rate of the shift shock increases as the smoother driving condition is required, and the drivability can be improved.

[Brief description of drawings]

FIG. 1 is a block diagram showing a schematic configuration of one system of a hydraulic control system in a hydraulic control device for an automatic transmission according to an embodiment of the present invention.

FIG. 2 is a flowchart showing a processing procedure of an electromagnetic pressure regulating valve main routine at the time of an upshift of an ECU used in a hydraulic control device for an automatic transmission according to an embodiment of the present invention.

FIG. 3 is a flowchart showing a processing procedure of a PID control subroutine of the ECU used in the hydraulic control device for the automatic transmission according to the embodiment of the present invention.

FIG. 4 is a time chart showing a situation in which a shift determination at the time of upshift occurs in a hydraulic control device for an automatic transmission according to an embodiment of the present invention.

FIG. 5 is a diagram showing an initial value FD of a throttle opening change speed and an electromagnetic pressure regulating valve control signal used during upshift of a hydraulic control device for an automatic transmission according to an embodiment of the present invention.
It is a map which shows the relationship with UT.

FIG. 6 is a map showing the relationship between the target shift time TH and the throttle opening change speed used during upshift of the hydraulic control device for an automatic transmission according to one embodiment of the present invention.

FIG. 7 is a characteristic diagram showing a relationship between an electromagnetic pressure regulating valve control signal SC and a clutch hydraulic pressure PC in a hydraulic control device for an automatic transmission according to an embodiment of the present invention.

FIG. 8 is a clutch hydraulic pressure P at the time of upshift of the hydraulic control device for an automatic transmission according to one embodiment of the present invention.
It is a time chart which shows the control range of C.

FIG. 9 is a time chart showing a situation in the hydraulic control device for an automatic transmission according to one embodiment of the present invention, when a shift determination is made at the time of kick down and shift down.

FIG. 10 is a map showing the relationship between the throttle opening change speed and the initial value FDUT of the electromagnetic pressure regulating valve control signal used during downshifting of the hydraulic control device for an automatic transmission according to one embodiment of the present invention. Is.

FIG. 11 is a map showing a relationship between a throttle opening change speed and a correction value used during a downshift of a hydraulic control device for an automatic transmission according to an embodiment of the present invention.

FIG. 12 is a block diagram showing a schematic configuration of one system of a hydraulic control system in a conventional hydraulic control system for an automatic transmission.

FIG. 13 is a time chart showing a control range of the clutch hydraulic pressure PC when the hydraulic control device for a conventional automatic transmission is upshifted.

[Explanation of symbols]

1 oil pump 2 Pressure regulator 3 ECU 6 Solenoid pressure regulator 7 clutch

Continuation of front page (51) Int.Cl. ⁷ identification code FI F16H 103: 14 F16H 103: 14 (58) Fields investigated (Int.Cl. ⁷ , DB name) F16H 59/00-61/12 F16H 61 / 16-61/24 F16H 63/40-63/48

Claims (2)

(57) [Claims] 1. An electronic control unit for directly and electronically controlling the operating pressure of a friction element arranged between a plurality of gear trains of a gear and a detecting unit for detecting a changing speed of a physical quantity that changes in accordance with an operating state of an internal combustion engine. and a controllable coupling state control means coupled state, the control on the basis of the change rate detected by said detecting means
Set the initial value of the signal and set it to the gear position when shifting down.
Turbine lower than the final turbine speed by a specified value
After reaching the rotation speed, the variation time of the control signal for controlling the operating pressure by the coupling state control means is set to the initial value.
Instead of the change speed detected by the detecting means.
A hydraulic control device for an automatic transmission, comprising: an operating pressure control means for appropriately changing the correction value to a correction value . 2. The operating pressure control means makes the fluctuation time of the operating pressure longer as the changing speed detected by the detecting means during upshifting is slower.
The hydraulic control device for the automatic transmission according to claim 1 .