KR100222829B1 - Hydraulic control system and its method of automatic transmission - Google Patents

Abstract

In order to reduce the shift shock and improve the feeling of shifting when shifting from the neutral range to the driving range, the neutral range to the reverse range, the driving range to the reverse range, and the reverse range to the driving range, the oil pressure generated from the oil pump Pressure control means to control the pressure, Manual valve for supplying hydraulic pressure selectively to the drive pressure or reverse pressure or the 2nd speed pipe and the 1st speed pipe in the corresponding range linked to the shifting lever, and the transformer to form a smooth shift mode during shifting. Hydraulic control means having a solenoid supply valve for supplying a reference pressure to solenoid valves that are duty controlled or on / off controlled by the mission control unit, damper clutch control means for damper clutch operation of the torque converter, and each friction element. Shift valves and clutch valves to distribute hydraulic supply to And a hydraulic distribution means for holding the first clutch valve for controlling the rear second friction element with the hydraulic pressure coming out through the ND control valve, and the hydraulic pressure coming out through the first clutch valve. Branching of the 2-3 and 4-3 shift valves for controlling the release of the first friction element and the operation of the third friction element, and the hydraulic line from the manual valve, the fourth friction element with the hydraulic pressure supplied through the branch line. It is connected to the 2 speed line pressure pipeline to move the valve spool to switch ports, and is connected to the pipeline of the ND control valve, characterized in that it consists of a 1-2 shift valve to control the first friction element Provide hydraulic control system of transmission.

Description

Hydraulic control system of automatic transmission and its control method

1 is a hydraulic circuit diagram showing an application state of an embodiment of the present invention.

Figure 2 is an enlarged cross-sectional view of the main part of the embodiment according to the present invention.

3 is a hydraulic circuit diagram showing the conversion from the neutral range to the traveling range of another embodiment of the present invention.

4 is a hydraulic circuit diagram showing the conversion from the neutral range to the reverse range of the embodiment according to the present invention.

5 is a hydraulic circuit diagram showing the conversion from the reverse range to the traveling range of the embodiment according to the present invention.

6 is a hydraulic circuit diagram showing the conversion from the traveling range to the reverse range of the embodiment according to the present invention.

The present invention relates to a hydraulic control system of the automatic transmission and a control method thereof, and more particularly, to a neutral range to a traveling range, a neutral range to a reverse range, a traveling range to a reverse range, a reverse range to a traveling range. The present invention relates to a hydraulic control system of an automatic transmission and a control method thereof for improving the transmission feeling at the time of low gear shift and increasing the reliability of the automatic transmission.

In general, an automatic transmission for a vehicle has a torque converter and a multistage shift mechanism connected to the torque converter, and hydraulically operated friction for selecting one of the gear stages of the transmission gear mechanism according to the driving condition of the vehicle. Contains an element.

The hydraulic control system of the automatic transmission for a vehicle operates the hydraulic pressure generated from the oil pump through a control valve to select and operate a friction element so that an appropriate shift can be automatically performed according to the driving state of the vehicle.

The hydraulic control system is a pressure control means for regulating the hydraulic pressure generated from the oil pump, manual and automatic shift control means that can form a shift mode, and shifting speed and response to form a smooth shift mode during shifting Hydraulic control means, damper clutch control means for actuating the damper clutch of the torque converter, and hydraulic distribution means for distributing a proper hydraulic supply to each friction element.

On the other hand, the friction element includes a first friction element and a friction element operating in the driving range second speed hold state, a third friction element and a fourth friction element operating in the reverse range state.

The first friction element is made of a band brake, and the second, third and fourth friction elements are made of a conventional multi-plate clutch.

Particularly, when shifting from the neutral range to the driving range, the third friction element with small rotational inertia is preferentially operated, and the fourth friction element with large rotational inertia is controlled later. There is a drawback to this.

In addition, there is a problem that a plurality of friction elements operate when shifting from the reverse range to the forward range so that a shift shock occurs when the shift is completed.

The present invention has been made to solve the problems of the prior art as described above, the object of the present invention is a neutral range to the driving range, the neutral range to the reverse range, the driving range to the reverse range, the driving range in the reverse range It is to provide a hydraulic control system of an automatic transmission that reduces shift shock and improves a shifting feeling at the time of shifting.

In order to realize the object of the present invention, the pressure adjusting means for regulating the hydraulic pressure generated from the oil pump to a constant line pressure, and the drive pressure or reverse pressure or two-speed pipeline and the first-speed pipeline in the range linked to the shift lever Hydraulic control means having a manual valve for selectively supplying hydraulic pressure and a solenoid supply valve for supplying a reference pressure to solenoid valves that are duty controlled or on / off controlled by a transmission control unit to form a smooth shift mode during shifting. And hydraulic distribution means for holding damper clutch control means for operating the damper clutch of the torque converter, shift valves and clutch valves for distributing the hydraulic pressure supply suitable for each friction element, and the hydraulic distribution means for ND control. First clutch for controlling the rear second friction element with hydraulic pressure through the valve Branching of the latch valve, the 2-3 and 4-3 shift valves for controlling the release of the first friction element and the operation of the third friction element with the hydraulic pressure coming out through the first clutch valve, and the hydraulic pipeline from the manual valve. The fourth friction element is controlled by the hydraulic pressure supplied through the branch pipe line, and the port friction is made by moving the valve spool connected to the second-speed line pressure line and connected to the pipeline of the ND control valve to connect the first friction element. It provides a hydraulic control system of an automatic transmission, characterized in that consisting of 1-2 shift valve to control.

In addition, the 1-2 shift valve has a first port through which a storage space is formed and a second speed pressure is input to one end, a second port configured to input a line pressure in a neutral state, and a low pressure through a pressure control valve. A third port through which a controlled control pressure is input, a fourth port for supplying hydraulic pressure introduced into the second port to operate the fourth friction element, and a fourth port for controlling the fourth friction element. A first discharge port formed for discharging the introduced hydraulic pressure, a fifth port for supplying hydraulic pressure introduced into the third port to the first friction element, and configured to selectively discharge the hydraulic pressure to the fifth port A valve node formed with a second discharge port; A first land that slides under the pressure of the hydraulic pressure introduced into the first port and closes or opens the second port and the fourth port, and a second land that selectively opens and closes the fourth port and the exhaust port; A third land for selectively opening and closing the fifth port for supplying hydraulic pressure to operate the third port and the first friction element, and selectively opening and closing the third port, the fifth port, the third port, and the second discharge port. A valve spool including a fourth land for discharging or drawing in the hydraulic pressure of the fifth port; It provides a hydraulic control system of an automatic transmission, characterized in that consisting of.

In addition, the bypass line is formed by branching the pipe connecting the fourth port and the fourth friction element of the 1-2 shift valve, and the hydraulic pressure is cut off from the 1-2 shift valve to the fourth friction element on the bypass channel. In the reverse direction, a hydraulic control system of an automatic transmission is provided, which is equipped with a check valve so that hydraulic pressure can flow freely.

A pressure regulating means for regulating the hydraulic pressure generated from the oil pump to a constant line pressure, a manual valve for selectively supplying hydraulic pressure to a drive pressure or a reverse pressure or a 2-speed pipe and a 1-speed pipe in a corresponding range in conjunction with a shift lever; Hydraulic control means having a solenoid supply valve for supplying a reference pressure to solenoid valves that are duty controlled or on / off controlled by a transmission control unit to form a smooth shift mode during shifting, and a damper clutch of a torque converter A method of controlling a hydraulic control system of an automatic transmission, comprising: a damper clutch control means for the engine; and hydraulic distribution means for retaining clutch valves and shift valves for distributing a proper hydraulic supply to each friction element. Activate the friction element, and the second friction when shifting from the neutral range to the driving range After operating by controlling the small, the pressure control solenoid valve is duty controlled by the transmission control unit (TCU) to release the fourth friction element, and when shifting from the neutral range to the reverse range, the fourth friction element is operated. The reverse friction is achieved by operating the third friction element while the second friction element is activated, and when shifting from the reverse range to the driving range, the second friction element is activated and after the third friction element is discharged, the fourth friction element is discharged to It provides a control method of the hydraulic control system of the automatic transmission, characterized in that the shift is made.

The hydraulic control system and the control method of the automatic transmission of the present invention operates a friction element having a large rotational inertia in the neutral range and minimizes the friction element that is operated at the forward and reverse range shifts.

With reference to the accompanying drawings, preferred embodiments of the present invention will be described in more detail.

1 is an oil pressure circuit diagram showing an embodiment according to the present invention, an oil pump 2 for pumping oil by a driving force of an engine, a torque converter 4 for transmitting engine power to an input shaft of a transmission, and A damper clutch (6) installed in the torque converter (4) to increase power transmission efficiency, a regulator valve (7) for varying the hydraulic pressure generated by the oil pump (2) according to the driving condition of the vehicle, and the pressure adjusting means described above. Torque converter control means for receiving the hydraulic pressure passing through to control the torque converter 4 and damper clutch control means for controlling the damper clutch 6 by receiving the hydraulic pressure passing through the torque converter control means.

In addition, the damper clutch control means is such that the port change is made by a damper clutch control solenoid valve S1 that is duty controlled by the transmission control unit (TCU).

On the other hand, the hydraulic pressure from the oil pump 2 is reduced in pressure and introduced to the damper clutch control means side or input to the N-R control valve 8 and the pressure control means side.

The pressure regulating means composed of the N-R control valve 8 and the pressure regulating valve 10 has a structure controlled by a pressure control solenoid valve S2 which is duty controlled by the transmission control unit TCU.

And the hydraulic pressure from the oil pump (2) is drawn into the manual valve (12).

The manual valve 12 has a structure in which the parking, reversing, neutral, and running range can be selected at the driver's will.

The manual valve 12 draws the hydraulic pressure drawn from the oil pump 2 toward the regulator valve 7 so that the pressure discharged through the oil pump 2 is constantly adjusted.

In addition, the manual valve 12 has a structure capable of drawing the hydraulic pressure received from the oil pump 2 to the shift control valve 14 side, the hydraulic distribution through the manual valve 12 and the shift control valve 14. It is made of a structure that can control a plurality of friction elements via means.

The hydraulic distribution means is composed of a first clutch valve 16, 2-3 and 4-3 shift valves 18, a second clutch valve 20, a 1-2 shift valve 22 and the like.

The first clutch valve 16 is connected to the four-speed pressure line 24 of the shift control valve 14, the reverse pressure line 26 of the manual valve 12, and the hydraulic line coming out of the nd control valve 28. It has a structure for controlling the second friction element 30 that operates in the running range one speed.

The 2-3 and 4-3 shift valves 18 are connected to the 3-speed pressure line 32 of the shift control valve 14 and the first clutch valve 16 and the 1-2 shift valve 22 in the reverse range. It has a structure for controlling the third friction element 34 to operate.

In addition, the 1-2 shift valve 22 has a structure in which a valve spool is movable by connecting the second speed pipe 36 coming out of the shift control valve 14 to one side, and having a manual valve 12 and an ND control valve ( It is made of a structure that can control the fourth friction element 38 that operates in the neutral range and the reverse range by branching the pipe connected to 28).

In addition, the 1-2 shift valve 22 is connected to the hydraulic line from the N-D control valve 28 has a structure for controlling the first friction element (40).

2 is an enlarged cross-sectional view of an essential part of an embodiment according to the present invention, in which a valve body 52 forming an appearance and a valve spool 54 slidably movable on one side of the valve body 52 are interposed. It is made of structure.

The valve body 52 has a structure in which a plurality of hydraulic ports are formed. The first port 56 is connected to the second speed pipeline 36 of the shift control valve 14 to move the valve spool 54. ), The second port 58 receiving the hydraulic pressure by branching the pipeline connecting the manual valve 12 and the ND control valve 28, and the hydraulic pressure discharged through the pipeline from the ND control valve 28 side are introduced. A third port 60, a fourth port 62 formed to control the fourth friction element 38 through the second port 58, and hydraulic pressure drawn in through the third port 60 A fifth port 64 for controlling the first friction element 40 is formed.

On the other hand, the first discharge port 66 is formed to release the hydraulic pressure introduced through the fourth port 62, and the second discharge port 68 is for discharging the hydraulic pressure introduced into the fifth port 64. ) Is formed.

In addition, the valve spool 54 which selectively opens and closes the port of the valve body 52 and slides therein moves the valve spool 54 under the pressure of the hydraulic pressure introduced from the second speed pipeline 36. The first land 70 is configured to selectively open and close the port 58 and the fourth port 62 to control the fourth friction element 38, and is spaced apart from the first land 70 by a predetermined distance. A second land 72 for selectively opening and closing the fourth port 62 and the first discharge port 66, and a third land for selectively opening and closing the third port 60 and the first discharge port 66 ( 74 and a fourth land 76 for selectively opening and closing the third port 60 and the fifth port 64 and the third port 60 and the second discharge port 68. .

On the other hand, the check valve is installed so that one side of the pipe connecting the fourth port 62 and the fourth friction element 38 is installed and the bypass pipe 78 is installed so that the hydraulic pressure can pass only in one direction on the bypass pipe 78. The structure which attaches 80 is comprised.

The check valve 80 has a structure in which the hydraulic pressure is blocked on the fourth friction element 38 side and the hydraulic pressure is freely flowed in the reverse direction.

The control method of the hydraulic control system of the automatic transmission made as described above is as follows when looking at the operating state in the N-D, N-R, R-D, D-R range.

<N range>

When the shift lever is moved to the N range position, as shown in FIG. 1, the valve spool of the manual valve 12, which operates in conjunction with the shift lever (not shown), moves and exits the oil pump 2. Hydraulic pressure is supplied to the ND control valve 28 side.

In addition, the hydraulic pressure is also introduced into the second port 58 side of the 1-2 shift valve 22 through the branch pipe line connected from the manual valve 12 to the N-D control valve 28 side.

The hydraulic pressure introduced into the second port 58 side of the 1-2 shift valve 22 actuates the fourth friction element 38 through the fourth port 62.

Therefore, the fourth friction element 38 is maintained at the neutral range.

<N → D range>

When the shift lever is moved and the shift lever is moved to the traveling range, the valve spool of the manual valve 12 linked thereto is moved, and as shown in FIG. 3, the manual valve 12 is positioned at the traveling range. The 1st speed | pressure which comes out is drawn in to the pressure control valve 10 side, and this 2nd friction element 30 is operated via the 1st clutch valve 16 via the ND control valve 28 via this pressure control valve 10. Let's go.

As described above, the duty control of the shift control solenoid S3 is controlled by the transmission control unit TCU with the line pressure drawn into the shift control valve 14 through the manual valve while the second friction element 30 is operating. While the hydraulic pressure is temporarily supplied to the second speed pressure pipe 36 of the shift control valve 14, the valve spool 54 of the 1-2 shift valve 22 is moved to the right in the drawing.

Then, the fourth friction element 38 operating in the neutral range is discharged through the first discharge port 66 of the 1-2 shift valve 22 to be released.

Therefore, only the second friction element 30 is operated in the driving range, so that the driving range 1 speed is fixed.

<N to R range>

When the shift lever is moved in the neutral range state, as shown in FIG. 4, the valve spool of the manual valve 12 linked thereto is moved to fix the reverse range state.

The reverse pressure from the manual valve 12 is then drawn into the first clutch valve 16.

At the same time, the pipeline leading to the first clutch valve 16 into the manual valve 12 is branched into the 2-3 and 4-3 shift valve 18.

The hydraulic pressure supplied to the 2-3 and 4-3 shift valves 18 actuates the third friction element 34 and at the same time acts as a release pressure of the first friction element 40.

Therefore, the reverse range is made by operating the third and fourth friction elements 34 and 38. When the reverse range is shifted, the fourth friction element 38 having a large rotational inertia maintains the operating state and the rotational inertia is relatively high. By operating only the small third friction element 34 is to reduce the shift shock.

<R → D range>

When the driver moves the shift lever to switch from the reverse range state to the forward range state, as shown in FIG. 5, the valve spool of the manual valve 12 linked with the shift lever moves to the driving range. It is fixed in a state.

Then, the first speed line pressure is introduced into the N-D control valve 28 through the pressure control valve 10 through the manual valve 12.

The hydraulic pressure introduced into the N-D control valve 28 controls the second friction element 30 through the first clutch valve 16.

And the hydraulic pressure acting on the third friction element 34 is discharged to the discharge port formed in the manual valve 12 through the 2-3 and 4-3 shift valve (18).

After the third friction element 34 is discharged, the hydraulic pressure acting on the fourth friction element 38 is released. This is because the shift control solenoid valve S3 is duty controlled by the transmission control unit TCU. The second speed pressure acts instantaneously on the shift control valve 14 so that the second speed pressure moves the valve spool of the 1-2 shift valve 22 to open the first discharge port 66 of the 1-2 shift valve 22. Through the discharge of the hydraulic is made.

Therefore, only the second friction element 30 acts in the driving range 1 speed fixed state.

<D → R range>

When the driver moves the shift lever to the reverse range according to the driving state, as described above, the manual valve is interlocked so that the valve spool is fixed to the reverse range.

The third and fourth friction elements are then operated in the same manner as described above in the N → R range.

In addition, as shown in FIG. 6, the second friction element operated in the driving range is released, and the pressure control solenoid valve S2 is turned on from the off state to the transmission control unit TCU. Duty controlled by the valve spool of the pressure control valve 10 is moved to the left in the figure.

Therefore, the line pressure drawn from the manual valve 12 side is cut off, and the hydraulic port drawn into the ND control valve 28 side communicates with the hydraulic port formed inside the pressure control valve 10 to discharge the hydraulic pressure. do.

Therefore, the hydraulic pressure acting on the second friction element 30 is released while the hydraulic pressure is discharged to the discharge port of the pressure control valve 10 via the ND control valve 28 through the first clutch valve 16. .

Therefore, only the third and fourth friction elements 34 and 38 operate to maintain the reverse range.

In the hydraulic control system and the control method of the automatic transmission of the present invention, the rotational tube is small after the minimum friction element is operated at the time of shifting each shift stage, and the friction element having a large rotational inertia is preferentially operated. By allowing the friction element to operate, the shifting feeling at the time of shifting is formed and the reliability of the automatic transmission can be increased.

Claims (4)

Pressure control means for regulating the oil pressure generated from the oil pump to a constant line pressure, a manual valve that selectively supplies drive pressure or reverse pressure in the corresponding range linked to the shifting lever, and a transmission to form a smooth shift mode during shifting. Hydraulic control means having a solenoid supply valve for supplying reference pressure to solenoid valves which are duty controlled or on / off controlled by the control unit, damper clutch control means for damper clutch operation of the torque converter, and each friction element. Hydraulic distribution means for retaining shift valves and clutch valves for distributing an appropriate hydraulic pressure supply, said hydraulic distribution means comprising: a first clutch valve for controlling a second friction element with hydraulic pressure coming out through an ND control valve; A first friction element with hydraulic pressure coming out of the first clutch valve Branches of the 2-3 and 4-3 shift valves, which control the release and operation of the third friction element, and the hydraulic line from the manual valve, control the fourth friction element by the hydraulic pressure supplied through the branch line. A hydraulic control system of an automatic transmission having a 1-2 shift valve connected to a line pressure line to move a valve spool to perform port switching, and connected to a line of an ND control valve to control a first friction element. The 1-2 shift valve has a first port through which an accommodation space is formed and a second speed pressure is input to one side, a second port configured to input a line pressure in a neutral state, and a low pressure through a pressure control valve. A third port through which a control pressure to be controlled is input, a fourth port for supplying hydraulic pressure introduced into the second port to operate the fourth friction element, and a fourth port for controlling the fourth friction element. The first discharge port is formed to discharge the drawn hydraulic pressure, the fifth port for supplying the hydraulic pressure introduced into the third port to the first friction element, and the hydraulic pressure introduced into the fifth port can be selectively discharged. A valve body having a second discharge port is formed so that the first body, the first land to slide or move under the pressure of the hydraulic pressure introduced into the first port to close or open the second port and the fourth port, and the fourth port And the exhaust A second land for selectively opening and closing the groove, a third land for selectively opening and closing the fifth port for supplying hydraulic pressure to operate the third port and the first friction element, the third port and the fifth port, A valve spool including a fourth land configured to selectively open and close the third port and the second discharge port to discharge or retract the hydraulic pressure of the fifth port; Hydraulic control system of the automatic transmission equipped with. 3. The method of claim 2, wherein a bypass pipe is formed by branching a conduit connecting the fourth port and the fourth friction element of the 1-2 shift valve to the fourth friction element from the 1-2 shift valve. Is a hydraulic control system of an automatic transmission equipped with a check valve so that the hydraulic pressure is blocked and the hydraulic pressure can flow freely in the reverse direction. A pressure regulating means for regulating the oil pressure generated from the oil pump to a constant line pressure, a manual valve which is selectively connected with the shift lever to drive pressure or reverse pressure or a 2-speed pipeline and a 1-speed pipeline in a corresponding range; Hydraulic control means having a solenoid supply valve for supplying a reference pressure to solenoid valves that are duty controlled or on / off controlled by a transmission control unit to form a smooth shift mode during shifting, and for damper clutch operation of a torque converter. A control method for a hydraulic control system of an automatic transmission, comprising: damper clutch control means, hydraulic shifting means for holding shift valves and clutch valves for distributing a proper hydraulic supply to each friction element. To operate the vehicle and shift it from the neutral range to the driving range. After operating by controlling the friction element, the pressure control solenoid valve is duty controlled by the transmission control unit (TCU) to release the fourth friction element, and the fourth friction element is operated when shifting from the neutral range to the reverse range. The reverse shift is made by operating the third friction element in the state, the second friction element is activated when the shift range is changed from the reverse range to the driving range, and the fourth friction element is operated after the hydraulic pressure for operating the third friction element is discharged. A control method of a hydraulic system of an automatic transmission in which the hydraulic pressure is discharged to shift the driving range.