KR19980036513A - Hydraulic Control System for Automatic Transmission - Google Patents

Abstract

In the four-speed automatic transmission, the line pressure control means for adjusting the hydraulic pressure supplied from the hydraulic pressure generating means to the line pressure in order to improve the shift response and the feeling of shifting by controlling each friction element independently in all the gear stages, the line pressure control Damper clutch control means for supplying / discharging the hydraulic pressure supplied from the means to the lubrication portion and the torque converter of the power train to operate / release the damper clutch, and to reduce the hydraulic pressure supplied from the line pressure control means to supply the solenoid valve control pressure. Range control means for converting port to supply hydraulic pressure supplied from the line pressure control means to the flow path corresponding to each selected range in conjunction with the operation of the shifting lever, the transmission control unit comprising a plurality of solenoid valves ON / OFF according to the control signal of (TCU) Shift control means for controlling the supply of the hydraulic pressure supplied from the range control means to be cut off corresponding to each shift stage, and operation of each friction element under the control of the transmission control unit (TCU); Hydraulic control means for controlling the release pressure, the hydraulic control means is installed on the conduit connecting the friction element and the friction element is controlled by the hydraulic pressure supplied / blocked from the shift control means to selectively supply / from the hydraulic control means and the shift control means A hydraulic control system for an automatic transmission comprising hydraulic distribution means for supplying / discharging the discharged hydraulic pressure to the selected friction element to activate / release the friction element.

Description

Hydraulic Control System for Automatic Transmission

The present invention relates to a hydraulic control system for a four-speed automatic transmission, and more particularly, to a hydraulic control system for an automatic transmission that improves shift response and shifting feeling by controlling each friction element with electronic logic.

In general, an automatic transmission for a vehicle is configured to convert the rotational power of the engine to a torque converter and to convert the converted rotational power according to the engine speed and the driving state of the vehicle in a multi-stage gear mechanism composed of a planetary gear device. have.

In order to convert the rotational power in the planetary gear unit as described above, the automatic transmission is fixedly fixed to the transmission housing so that it can be operated as a reaction force element through a brake means, which is a friction element, to a specific element of the planetary gear unit, It is provided with a hydraulic control system which is variably connected to the input shaft so as to operate as an input element via another friction element, a clutch means, and operates and releases the friction elements.

The hydraulic control system of the automatic transmission uses the hydraulic pressure generated by the mutual drive of the drive gear mounted on the oil pump drive hub driven together with the pump impeller of the torque converter and the driven gear engaged thereto. It is configured to supply the lubrication portion of the planetary gear device, the damper clutch mounted to the torque converter and the respective friction elements for controlling each element of the planetary gear device.

Although many hydraulic control systems for automatic transmissions as described above are known, shift responsiveness and shifting feelings are controlled by applying hydraulic logic to control the friction elements operated and released at specific gear stages by the control pressure of other friction elements. There is a disadvantage of lowering.

Therefore, the present invention has been invented to solve the above problems, an object of the present invention is to provide a hydraulic control system for an automatic transmission to improve the shift response and shifting feeling by independently controlling each friction element with electronic logic at all shift stages. To provide.

In order to realize this, the hydraulic control system for an automatic transmission according to the present invention includes a line pressure control means for adjusting the oil pressure supplied from the oil pressure generating means to line pressure, and the oil pressure supplied from the line pressure control means to the lubrication portion and torque of the power train. Damper clutch control means for operating / releasing the damper clutch by supplying / discharging to the converter, reducing pressure control means for reducing the hydraulic pressure supplied from the line pressure control means and supplying it to the solenoid valve control pressure, and selected in conjunction with the operation of the shift lever. Range control means for port conversion to supply the hydraulic pressure supplied from the line pressure control means to the flow path corresponding to each range, consisting of a plurality of solenoid valves are controlled on / off in accordance with the control signal of the transmission control unit (TCU) From the range control means A shift control means for shutting off the supplied hydraulic pressure corresponding to each shift stage, and a hydraulic control for adjusting the hydraulic pressure supplied from the range control means to actuation / release pressure of each friction element according to the control of the transmission control unit (TCU) Means, the hydraulic pressure is provided on the pipeline connecting the hydraulic control means and the friction element and controlled by the hydraulic pressure supplied / disconnected from the shift control means to supply the hydraulic pressure selectively supplied / discharged from the hydraulic control means and the shift control means to the selected friction element. Hydraulic distribution means for supplying / discharging to actuate / release the friction element.

The hydraulic control system for an automatic transmission configured as described above controls the hydraulic distribution means by the shift control means to form a flow path, and then independently selects the friction elements selected by the hydraulic pressure controlled by the hydraulic control means and the hydraulic pressure supplied from the shift control means. To activate / release.

BEST MODE Hereinafter, preferred configurations and operations of the present invention will be described in detail with reference to the accompanying drawings.

1 is a hydraulic circuit diagram formed in the 1-2 shift process of the hydraulic control system for automatic transmission according to the present invention.

Figure 2 is a hydraulic circuit diagram formed in the 2-3 shift process of the hydraulic control system for automatic transmission according to the present invention.

Figure 3 is a hydraulic circuit diagram formed in the 3-4 shift process of the hydraulic control system for automatic transmission according to the present invention.

Figure 4 is a hydraulic circuit diagram formed in the 4-3 shift process of the hydraulic control system for automatic transmission according to the present invention.

5 is a hydraulic circuit diagram formed in the 3-2 shift process of the hydraulic control system for automatic transmission according to the present invention.

Figure 6 is a hydraulic circuit diagram formed in the 2-1 shift process of the hydraulic control system for automatic transmission according to the present invention.

7 is a hydraulic circuit diagram formed in a 4-2 skip shifting process of the hydraulic control system for an automatic transmission according to the present invention.

1 is a hydraulic circuit diagram formed in the D range 1-2 shifting process of the hydraulic control system for an automatic transmission according to the present invention, supplying the hydraulic pressure generated by the hydraulic generating means to each friction element corresponding to each shift stage. It is configured to realize automatic transmission by independently operating / releasing selected friction elements while discharging / discharging.

That is, the oil pump 3 mounted on the pump dry hub of the torque converter 1 continuously generates hydraulic pressure at the same time as the engine is driven, so that the oil pump 3 can be supplied to the regulator valve 5 which is a line pressure control means. Is connected.

The regulator valve 5 is a torque converter control valve of a damper clutch control means installed to control the hydraulic pressure supplied to the line pressure line 7 to the lubrication portion of the transaxle and the damper clutch built in the torque converter 1. (9), damper clutch control valve (11) and torque converter (1) are connected by conduits (13, 15, 17, 19, 21) for supply / discharge.

On the other hand, the reducing valve 23 of the reducing pressure control means connected to the line pressure line 7 and supplied with the line pressure adjusted by the regulator valve 5 transmits the damper clutch control valve 11 to the transmission control unit (TCU). Damper clutch control solenoid valve 25 to control in accordance with the control signal of the) and the hydraulic pressure control means are connected to the pipeline 27, 29 so that the reducing pressure can be supplied.

The conduit 27 is connected so that the regulator valve 5 can supply hydraulic pressure to the high-low pressure valve 31 which controls the line pressure to high / low, and the high-low valve 31 is a damper clutch. The control solenoid valve 25 is connected to the conduit 33 so as to be activated / inactive as the on / off operation is performed. The hydraulic pressure supplied from the valve 37 can be actuated / non-actuated to the regulator valve 5.

In addition, the line pressure line 7 is connected to a manual valve 37 which forms a flow path corresponding to each range in conjunction with the operation of the shift lever, and the manual valve 37 is parked (P) and reversed (R). It is configured to select the neutral (N) and traveling (D, 2, L) ranges.

In addition, the manual valve 37 supplies hydraulic pressure to the regulator valve 5 when selecting the forward and backward directions so that the regulator valve 5 can be adjusted to the appropriate line pressure for each range. Is connected.

In addition, the manual valve 37 is connected to the first, second and third shift control solenoid valves 43, 45, 47 and the conduit 49 of the shift control means so as to supply / discharge the hydraulic pressure to the shift control means and the hydraulic control means. The first and second pressure control valves 51 and 53 of the hydraulic control means are connected to the conduit 55 and connected to the NR control valve 57 and the conduit 59, respectively.

The first, second, and third shift control solenoid valves 43, 45, and 47 are arranged to be turned on / off according to a control signal of a transmission control unit (TCU) to control respective valves of the hydraulic distribution means. .

The first and second pressure control valves 51 and 53 of the hydraulic control means are operated by the first and second pressure control solenoid valves 61 and 63 which are duty controlled according to the control signal of the transmission control unit TCU. consist of.

On the other hand, the first and second pressure control valves 51 and 53 and the NR control valve 57 are supplied with the reducing pressure reduced by the reducing valve 23 by the first and second pressure control solenoid valves 61 and 63. It is connected to the reducing valve 23 and the above-described conduit 29 so as to be controlled.

The hydraulic pressure controlled by the first and second pressure control valves 51 and 53 and the NR control valve 57 operated by the first and second pressure control solenoid valves 61 and 63 as described above is used to select hydraulic pressure. Hydraulic distribution means for forming a flow path by the first, second and third shift control solenoid valves 43, 45 and 47 are provided between the hydraulic control means and the friction element so as to be supplied / discharged.

The hydraulic distribution means includes a plurality of spool valves capable of changing the flow path.

That is, the rear clutch discharge valve 65 is connected to the pipeline 69 branched from the pipeline 49 connected to the second pressure control valve 53 and the pipeline 67 and connected to the manual valve 37. It is connected to the release valve 71 and the conduit 73 and is connected to the rear clutch 75 and the conduit 77.

Accordingly, the rear clutch discharge valve 65 is controlled by the first shift control solenoid valve 43 to supply the hydraulic pressure supplied to the conduit 67 to the rear clutch 75 or the hydraulic pressure supplied to the conduit 69. It is configured to include a valve spool 79 for supplying the hydraulic pressure supplied to the conduit 67 at the same time as the supply (75) to the servo release valve 71 through the conduit (73).

The servo application valve 81 is provided with a low reverse brake / servo supply valve 87 for supplying the hydraulic pressure supplied from the first pressure control valve 51 to the servo application 85 of the kickdown band brake 83. It is connected to the conduit 89, connected to the pipelines 91 and 93 branched from the conduit 49 connected to the manual valve 37, and is connected to the end clutch valve 95 and the conduit 97.

Therefore, the servo application valve 81 is controlled by the third shift control solenoid valve 47 to supply the hydraulic pressure supplied to the conduit 89 to the servo application 85 and the hydraulic pressure supplied to the conduit 93. Supply to the end clutch valve 95 connected to the conduit 97 or the hydraulic pressure supplied to the conduit 91 to the servo application 85 and at the same time the hydraulic pressure supplied to the conduit 89 through the conduit 97 It consists of a structure including a valve spool 98 to be supplied to the end clutch (95).

The end clutch valve 95 is connected to the servo release valve 71 for supplying / discharging hydraulic pressure to the servo release 99 by a conduit 101 and is connected to the servo release 99 by a conduit 103. .

Therefore, the end clutch valve 95 supplies the hydraulic pressure supplied from the conduit 97 to the end clutch 105 and simultaneously supplies the hydraulic pressure supplied to the conduit 101 to the conduit 103 to act on the servo release 99. To discharge the hydraulic pressure for operating the servo release 99 to the conduit 103 and to discharge the hydraulic pressure for operating the end clutch 105 to the servo release valve 71 connected to the conduit 101. And a valve spool 107 for releasing 105.

The servo release valve 71 is controlled by the second shift control solenoid valve 45 to end-clutch the hydraulic pressure supplied to the conduits 67 and 73 communicated by the operation of the rear clutch discharge valve 65. It includes a valve spool 109 to supply the servo release 99 or to discharge the hydraulic pressure supplied to the pipelines 101 and 103 communicated by the operation of the valve 95.

In addition, the low reverse brake / servo application valve 87 is connected to the first pressure control valve 51 by a conduit 111, and is connected to the NR control valve 57 by a conduit 113, and a low reverse brake 115. ) Is connected to the pipeline 117 to supply the hydraulic pressure or to discharge the supplied hydraulic pressure.

In addition, the low reverse brake / servo application valve 87 is connected to the conduit 119 to receive a control pressure from the manual valve 37 when the L range is selected, and is supplied to the conduit 39 when the reverse direction is applied to the front clutch 121. It is connected to the pipeline 123 branched from the pipeline 39 to receive the hydraulic pressure to operate the.

Therefore, the low reverse brake / servo application valve 87 supplies the hydraulic pressure supplied to the conduit 111 when the D range is selected to the conduit 89, and is controlled by the hydraulic pressure supplied to the conduit 123 when the reverse range is NR controlled. The hydraulic pressure supplied to the conduit 113 connected to the valve 57 is supplied to the servo application 85 through the conduit 87, and is controlled by the hydraulic pressure supplied to the conduit 119 when the L range is selected. It includes a valve spool 125 to supply the hydraulic pressure supplied to the pipe line 117 to operate the low reverse brake (115).

The hydraulic control system for an automatic transmission configured as described above is automatically operated as the transmission control unit (TCU) controls each solenoid valve on / off or duty according to the operation of the manual valve 37 and the opening speed of the vehicle speed and the throttle valve. Shifting is realized.

When the engine is first started, the oil pressure generated by the oil pump 3 is controlled to a constant line pressure in the regulator valve 5, and is supplied to the line pressure line 7 and is simultaneously supplied to the torque converter control valve 9.

As the transmission control unit (TCU) controls the damper clutch control solenoid valve 25 according to the driving condition of the vehicle, the reducing pressure supplied to the conduit 27 from the reducing valve 23 is applied to the damper clutch control valve ( 11) to actuate / deactivate the damper clutch control valve 11 while supplying / discharging or discharging / supplying hydraulic pressure to the conduits 17 and 19 to release / actuate the damper clutch.

(1-2 shift)

When the vehicle speed and the throttle valve opening ratio increase in the D range 1 speed state, as shown in FIG. 1, the transmission control unit (TCU) includes the first, second, and third shift control solenoid valves 43, 45, and 47. Control all on.

Therefore, the hydraulic pressure supplied to the conduit 49 connected to the manual valve 37 does not exert an acting force on the valve spools 79, 109, 107, 98 of the respective valves 65, 71, 81, 95 of the hydraulic distribution means.

Therefore, the rear clutch discharge valve 65 communicates the conduits 67 and 77, and the servo application valve 81 communicates the conduit 89 with the servo application 85.

At the same time, the transmission control unit TCU controls the second pressure control solenoid valve 63 in the off state, and duty control the first pressure control solenoid valve 61 from on to off.

Accordingly, the second pressure control valve 53 continuously supplies hydraulic pressure to the conduits 67 and 77 communicated by the rear clutch discharge valve 65 as in the first speed so that the rear clutch 75 continues to operate.

The first pressure control valve 51 is operated by the first pressure control solenoid valve 61 to communicate the conduits 55 and 111.

Therefore, the hydraulic pressure supplied from the manual valve 37 is passed through the conduits 55 and 111, the low reverse brake / servo application valve 87, and the conduits 111 and 89 communicated by the servo application valve 81. It is supplied to the servo application 85 of the kickdown band brake 83, and the kickdown band brake 83 is operated to realize the second speed.

That is, the servo application 85 of the kickdown band brake 83 is operated controlled by the duty control pressure of the first pressure control solenoid valve 61.

(2-3 shifts)

When the vehicle speed and the throttle valve opening ratio increase in the second speed state as described above, as shown in FIG. 2, the transmission control unit TCU may include the first, second, and third shift control solenoid valves 43, 45, and 47. ) From on to off.

Therefore, the hydraulic pressure supplied to the conduit 49 connected to the manual valve 37 exerts an acting force on the valve spools 79, 109, 107, 98 of the respective valves 65, 71, 81, and 95 of the hydraulic distribution means. (79, 109, 107, 98) are all moved to the right as seen in the drawing.

Therefore, the rear clutch discharge valve 65 communicates the conduits 69 and 77 and at the same time communicate the conduits 67 and 73, the servo application valve 81 communicates the conduits 73 and 101, and the end clutch The valve 95 communicates the conduits 101 and 103 and at the same time communicates the conduit 97 to the end clutch 105, and the servo application valve 81 connects the conduit 91 to the servo application 85. At the same time, the pipes 89 and 97 are communicated.

Accordingly, the rear clutch 75 is continuously operated by the hydraulic pressure supplied from the conduit 49 to the branched conduit 69, and the servo application 85 is supplied from the conduit 49 to the branched conduit 91. It continues to work.

At the same time, the transmission control unit TCU duty-controls the second pressure control solenoid valve 63 from off to on to off to operate the second pressure control valve 53.

Therefore, the hydraulic pressure supplied to the conduit 55 is controlled by the second pressure control valve 53, and the controlled hydraulic pressure is supplied to the rear clutch discharge valve 65, the servo release valve 71, and the end clutch valve 95. It is supplied to the servo release 99 through the communication lines (67, 73, 101, 103) communicated with each other to release the kickdown band brake (83).

That is, the servo release 99 for releasing the kickdown band brake 83 is operated controlled by the duty control pressure of the second pressure control solenoid valve 63.

In addition, the transmission control unit TCU controls the first pressure control solenoid valve 61 from off to on to off duty to operate the first pressure control valve 51.

Accordingly, the hydraulic pressure supplied to the conduit 55 is controlled by the first pressure control valve 51, and the controlled hydraulic pressure is controlled by the low reverse brake / servo application valve 87 and the conduits 111 and 89 and the servo. It is supplied to the end clutch 105 through the pipelines 89 and 97 and the end clutch valve 95 communicated by the applicator valve 81, and operates to realize the third speed.

That is, the end clutch 105 is operationally controlled by the duty control pressure of the first pressure control solenoid valve 61.

(3-4 shifts)

When the vehicle speed and the throttle valve opening ratio increase in the three speed state as described above, as shown in FIG. 3, the transmission control unit TCU turns off the first and third shift control solenoid valves 43 and 47 from the off state. It controls to ON, and controls the 2nd shift control solenoid valve 45 to OFF.

Therefore, the hydraulic pressure supplied to the conduit 49 connected to the manual valve 37 exerts an acting force only on the servo release valve 71 of the hydraulic distribution means and the valve spools 109 and 107 of the end clutch valve 95. The spools 109 and 107 are both moved to the right as seen in the drawing, and no acting force is applied to the valve spools 79 and 98 of the rear clutch discharge valve 65 and the servo application valve 81. Valve spools 79 and 98 of 65 and 85 are moved to the left in the figure.

Therefore, the rear clutch discharge valve 65 communicates the conduits 67 and 77 and at the same time communicates the conduit 73 to the discharge port EX.

Therefore, the hydraulic pressure supplied to the servo release 99 is discharged through the pipelines 103, 101, and 73 to release it, and the transmission control unit (TCU) turns the second pressure control solenoid valve 63 off to on. Since the duty control operates the second pressure control valve 53, the hydraulic pressure which operated the rear clutch 75 is discharged through the pipelines 77 and 67 and the second pressure control valve 53 to release it.

That is, the rear clutch 75 is released controlled by the duty control pressure of the second pressure control solenoid valve 63.

At the same time, the transmission control unit TCU duty-controls the first pressure control solenoid valve 61 from off to on to off to operate the first pressure control valve 51.

Therefore, the hydraulic pressure supplied to the conduit 55 is supplied to the servo application 85 through the connected conduits 111 and 89 to operate the kickdown band brake 83 to realize the four speeds.

That is, the servo application 85 for operating the kickdown band brake 83 is controlled by the duty control pressure of the first pressure control solenoid valve 61.

(4-3 shift)

When the vehicle speed and the throttle valve opening ratio are reduced in the above four speed state, as shown in FIG. 4, the transmission control unit (TCU) shifts the first and third shift control solenoid valves 43 and 47 while shifting. After shifting to ON, it controls to OFF and always controls the 2nd shift control solenoid valve 45 to OFF.

The transmission control unit TCU duty-controls the second pressure control solenoid valve 63 from on to off when the gear is shifted first, that is, while the first and third shift control solenoid valves 43 and 47 are on. Activate the pressure control valve (53).

Therefore, the hydraulic pressure supplied to the conduit 55 is supplied to the rear clutch 75 through the conduits 67 and 77 communicated by the rear clutch discharge valve 65 to operate it.

That is, the rear clutch 75 is operated controlled by the duty control pressure of the second pressure control solenoid valve 63.

At the same time, the transmission control unit TCU duty-controls the first pressure control solenoid valve 61 from off to on to off to operate the first pressure control valve 51.

Therefore, the hydraulic pressure supplied to the conduit 55 is supplied to the servo application 85 through the conduits 11 and 89 and the servo application valve 81 communicated by the low reverse brake / servo application valve 87. It works.

The hydraulic pressure supplied to the conduit 49 is supplied to the end clutch 105 through the conduit 97 communicated by the conduit 93 and the servo application valve 81 branched from the conduit 49 to continue operation thereof. Let's do it.

In this state, the transmission control unit (TCU) controls the first and second shift control solenoid valves 43 and 47 from on to off so that the valve spool 79 of the rear clutch discharge valve 65 and the servo application valve ( The valve spool 98 of 81 is moved to the right as seen in the drawing.

Therefore, the rear clutch 75 is continuously operated by the hydraulic pressure supplied to the branched conduit 69 from the conduit 49 connected to the manual valve 37.

In addition, the duty-controlled hydraulic pressure in the second pressure control valve 53 is a conduit 67, 73, 101, 103 communicated by the rear clutch discharge valve 65, the servo release valve 71, and the end clutch valve 95. Is supplied to the servo release 99 to release the kick-down band brake 83 to realize the third speed.

That is, the servo release 99 for releasing the kickdown band brake 83 is operated controlled by the duty control pressure of the second pressure control solenoid valve 63.

The servo applicator 85 continues to be operated by the hydraulic pressure supplied to the conduit 91, and the hydraulic pressure controlled by the first pressure control valve 51 is the low reverse brake / servo applicator 87 and the servo aer. It is supplied to the conduits 111, 89, 97 communicated by the fly valve 81 and the end clutch valve 95 to continue to operate the end clutch 105.

(3-2 shift)

When the vehicle speed and the throttle valve opening ratio are reduced in the three-speed state as described above, as shown in FIG. 5, the transmission control unit TCU may include the first, second, and third shift control solenoid valves 43, 45, and 47. ) From off to on.

Therefore, the hydraulic pressure supplied to the conduit 49 fails to exert an acting force on the valve spools 79, 109, 107, and 98 of the valves 43, 71, 79, and 81 of the hydraulic distribution means, and thus the valve spools 79, 109, and 107. , 98) are shifted to the left in the drawing.

Therefore, the rear clutch discharge valve 65 communicates the conduits 67 and 77, and the servo release valve 71 blocks the conduits 73 and 101, and simultaneously communicates the conduit 101 to the discharge port EX. In addition, the end clutch valve 95 communicates the conduit 101 with the end clutch 105 and simultaneously communicates the conduit 103 with the discharge port EX, and the servo application valve 81 opens the conduit 89. It communicates with the servo application 85.

Therefore, the rear clutch 75 continues to be operated by the hydraulic pressure supplied to the conduits 67 and 77, and the hydraulic pressure which has been operated on the end clutch 105 passes through the end clutch valve 95 and the conduit 101 through the servo release valve. Discharged to 71 to release it, the hydraulic pressure acting on the servo release 99 is discharged through the pipeline 103 and the end clutch valve 95 to release it.

At the same time, the transmission control unit (TCU) duty-controls the first pressure control solenoid valve from off to on to off to communicate with the low reverse brake / servo application valve 87 and the servo application valve 81. The two speeds are realized by supplying the servo application 85 through the conduits 111 and 89 to operate the kickdown band brake 83.

That is, the servo application 85 for operating the kickdown band brake 83 is operated controlled by the duty controlled hydraulic pressure in the first pressure control solenoid valve 61.

(2-1 shift)

When the vehicle speed and the throttle valve opening rate decrease in the second speed state as described above, as shown in FIG. 6, the transmission control unit TCU may include the first, second, and third shift control solenoid valves 43, 45, and 47. ) To keep everything on.

Therefore, the hydraulic distribution means forms the same flow path as in the second speed.

In this state, the transmission control unit TCU duty-controls the first pressure control solenoid valve 61 from off to on to operate the first pressure control valve 51.

Therefore, the hydraulic pressure that operated the servo applicator 85 is the first reverse pressure control valve 51 and the conduits 111 and 89 communicated by the low reverse brake / servo applicator valve 87 and the servo application valve 81. It discharges through and releases the servo application 85, and releases the kickdown band brake 83, and implement | achieves one speed | rate.

In other words, the servo application 85 for releasing the kickdown band brake 83 is released controlled by the duty control pressure of the first pressure control solenoid valve 61.

(4-2 skip shifting)

When the vehicle speed and the throttle valve opening rate suddenly increase in the four-speed state as described above, as shown in FIG. 7, the first and second shift control solenoid valves 43 and 45 during the transmission control unit TCU are shifted. ) Are controlled on and off, and after shifting, the control is turned off and on, and the third sift control solenoid valve 47 is always controlled to be off.

When the gear shift is first performed, that is, when the first and third shift control solenoid valves 43 and 47 are on and off, respectively, the servo application 85 is continuously operated by the hydraulic pressure supplied to the conduit 91. The mission control unit TCU duty-controls the first pressure control solenoid valve 61 from off to on to operate the first pressure control valve 51.

Therefore, the hydraulic pressure for operating the end clutch 105 is controlled by the pipelines 97, 89, 111 formed by the end clutch valve 95, the servo application valve 81, and the low reverse brake / servo application valve 87. 1 is discharged through the pressure control valve 51 to release the end clutch 105.

That is, the end clutch 105 is released controlled by the duty control pressure of the first pressure control solenoid valve 61.

The transmission control unit TCU duty-controls the second pressure control solenoid valve 63 from on to off to operate the second pressure control valve 53.

Therefore, the hydraulic pressure supplied to the conduit 55 is supplied to the rear clutch 75 through the conduits 67 and 77 communicated by the rear clutch discharge valve 65 to operate it to realize the 4-2 skip shift.

That is, the rear clutch 75 is operated controlled by the duty control pressure of the second pressure control solenoid valve 63.

In this state, the transmission control unit (TCU) controls the first and second shift control solenoid valves 43 and 45 to be on and off, respectively, so that the valve spool 79 of the rear clutch discharge valve 65 can be seen in the drawing. The valve spools 109 and 107 of the servo release valve 71 and the end clutch valve 95 are moved to the left side in the drawing.

Accordingly, the rear clutch 75 is continuously operated by the hydraulic pressure supplied to the conduits 69 and 77 communicated by the rear clutch discharge valve 65.

As described above, the hydraulic control system for an automatic transmission according to the present invention independently controls each friction element at all shift stages by hydraulic control means, and enables 4-2 skip shifting, thereby improving shifting response and shifting feeling. have.

Claims (8)

Line pressure control means for adjusting the oil pressure supplied from the oil pressure generating means to the line pressure, Damper clutch for operating / releasing the damper clutch by supplying / discharging the oil pressure supplied from the line pressure control means to the lubrication portion and the torque converter of the power train The control means, the reducing pressure control means for reducing the hydraulic pressure supplied from the line pressure control means and supplying the solenoid valve control pressure, the hydraulic pressure supplied from the line pressure control means with a flow path corresponding to each selected range in conjunction with the operation of the shift lever. It is composed of a range control means for converting the port so that it can be supplied, and a plurality of solenoid valves on / off control in accordance with the control signal of the transmission control unit (TCU) so that the hydraulic pressure supplied from the range control means corresponding to each shift stage Shift control to cut off the supply Means, hydraulic control means for adjusting the hydraulic pressure supplied from the range control means to the operation / release pressure of each friction element under the control of the transmission control unit (TCU), on the pipeline connecting the hydraulic control means and the friction element A hydraulic distribution means installed and controlled by hydraulic pressure supplied / disconnected from the shift control means to supply / discharge hydraulic pressure selectively supplied / discharged from the hydraulic control means and the shift control means to the selected friction element to operate / release the friction element. Hydraulic control system for automatic transmission comprising. The method according to claim 1, wherein the shift control means is controlled on / off by a transmission control unit (TCU) so as to inactivate / act the hydraulic pressure supplied from the manual valve of the range control means to each valve of the hydraulic distribution means; Hydraulic control system for automatic transmission with 2, 3 shift control solenoid valves. 2. The rear clutch discharge according to claim 1, wherein the hydraulic pressure distribution means distributes the hydraulic pressure supplied from the range control means and the hydraulic control means to the friction element and is connected to selectively supply or discharge the hydraulic pressure to the rear clutch. A valve, a servo application valve having a structure connected to supply or discharge the hydraulic pressure to a servo application of a kickdown band brake as a friction element, and connected to supply or discharge the hydraulic pressure to an end clutch as a friction element An end clutch valve having a structure, and a servo release valve having a structure that is connected to supply or discharge the hydraulic pressure supplied from the hydraulic control means to the servo release of the kick-down band brake, the hydraulic pressure supplied from the hydraulic control means Inn Low Reverse Lake and servo control low-reverse made of a structure which is connected so as to supply to the ply or exhaust brake / servo the applied hydraulic pressure control system for an automatic transmission comprising a valve. 4. The rear clutch discharge valve according to claim 3, wherein the rear clutch discharge valve selectively supplies hydraulic pressure supplied to the hydraulic control means to the rear clutch and the servo release valve, and when the hydraulic pressure supplied from the hydraulic control means is supplied to the servo release valve. A hydraulic control system for an automatic transmission comprising a valve spool controlled to supply hydraulic pressure supplied from the means to the rear clutch. 4. The servo control valve according to claim 3, wherein the servo application valve selectively supplies hydraulic pressure supplied from the hydraulic control means to the servo application and the end clutch valve, and when the hydraulic pressure supplied from the hydraulic control means is supplied to the end clutch valve. A hydraulic control system for an automatic transmission comprising a valve spool controlled to supply the hydraulic pressure supplied from the servo application. 4. The end clutch valve according to claim 3, wherein the end clutch valve supplies or discharges the hydraulic pressure supplied from the servo application to the end clutch, and the hydraulic pressure supplied from the servo release valve is supplied when the hydraulic pressure supplied from the servo application is supplied to the end clutch. Hydraulic control system for automatic transmission comprising a valve spool controlled to be supplied to the release. 4. The servo release valve according to claim 3, wherein the servo release valve controls the end clutch valve to supply the hydraulic pressure supplied from the rear clutch discharge valve to the servo release, or to control the servo release discharge hydraulic pressure from the end clutch valve. Hydraulic control system for an automatic transmission comprising a valve spool. 4. An automatic transmission according to Claim 3, wherein the low reverse brake / servo application valve includes a valve spool controlled to selectively supply the hydraulic pressure supplied from the hydraulic control means to the servo reverse valve and the low reverse brake which is a friction element. Hydraulic control system.