KR100448378B1 - Hydraulic control system of automatic transmission - Google Patents

Abstract

In order to independently control the engagement clutch and the release clutch when shifting 2 → 3 and 4 → 3, the shift control is easy, the shifting feeling is improved, and the 1 ↔ 3 speed skip shift is possible;

The hydraulic pressure supplied from the first and second pressure control valves and the manual valve linked to the selector lever operated by the driver, the shift control valve controlled by the two solenoid valves, and the pressure control valves are moved forward. Rear clutches operating in 2 and 3 speeds, kick-down brakes operating in 2nd and 4th forwards, front clutches operating in 3rd and 4th forwards, end clutches operating in 3rd and 4th forwards, and reverse Including a plurality of spool valve to selectively supply hydraulic pressure to the low-reverse brake operating in

A 2-3 / 4-3 shift valve which is controlled by three speeds and four speeds and switches the flow path so as to selectively supply the hydraulic pressure of the third speed or the second pressure control valve to the rear clutch and the front clutch; And a 4-3 shift valve for supplying the hydraulic pressure supplied from the 2-3 / 4-3 shift valve to the rear clutch via the rear clutch release valve while being controlled by the operating pressure of the end clutch and the operating pressure of the front clutch. Provides a hydraulic control system of an automatic transmission for a vehicle.

Description

HYDRAULIC CONTROL SYSTEM OF AUTOMATIC TRANSMISSION}

The present invention relates to a hydraulic control system of an automatic transmission.

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

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

Referring to the conventional configuration of such a hydraulic control system, as shown in Figure 9, the hydraulic pressure generated from the oil pump 200 is a pressure regulating valve 202, a torque converter control valve 204, a damper clutch control valve ( 206).

In addition, a part of the hydraulic pressure generated from the oil pump 200 is supplied to the reducing valve 208 and the manual valve 210, the constant pressure reduced in the reducing valve 208 is the first pressure control valve ( 212 and the second pressure control valve 214 is controlled to the control pressure of the speed change stage.

A part of the hydraulic pressure supplied to the first and second pressure control valves 212 and 214 is supplied to the NR control valve 216, and the hydraulic pressure flows when the manual valve 210 is in the travel (D) range. The pipeline 218 is connected to a shift control valve 220 for switching the flow path under the control of the first solenoid valve S1 and the second solenoid valve S2, and is configured to be manually and automatically shifted together with the manual valve 210 described above. Control is made.

The first speed pipe 222 is branched on the pipe 218 and connected to the first and second pressure control valves 212 and 214 controlled by the third and fourth solenoid valves S3 and S4. Supply pressure.

The shift control valve 220 is connected to the second speed pipeline 224, the third speed pipeline 226, the fourth speed pipeline 228, the second speed pipeline 224 is a 1-2 shift valve 230 and the control It is connected to the switch valve 232 and the fail-safe valve 234, the three-speed pipeline 226 is branched into two pipelines 236, 238 so that the first branch pipeline 236 is a pipeline 2-3 The fourth branch line 238 supplies hydraulic pressure to the control switch valve 232 and the end clutch valve 242.

In addition, the four-speed pipeline 228 is connected to the rear clutch release valve 244 and the 2-3 / 4-3 shift valve 240, and part of the pressure regulating valve 202 through the high-low pressure valve 246 ) To adjust the line pressure.

The timing control channel 248 of the manual valve 210 is connected to the control switch valve 232 and the high-low pressure valve 246 and controlled by the fifth solenoid valve S5.

In addition, when the manual valve 210 is in the reverse (R) range, the hydraulic pressure supplied to the reverse first control conduit 250 is transferred through the rear clutch release valve 244 and the 2-3 / 4-3 shift valve 240. The hydraulic pressure can be supplied to the release side chamber of the front clutch C4 and the kick-down servo C2, and a control pressure of the fail-safe valve 234 is supplied.

The hydraulic pressure supplied to the reverse second control pipe 252 supplies the hydraulic pressure to the low-reverse brake C5 through the NR control valve 216 and the 1-2 shift valve 230, and the second pressure control. An accumulator AC is disposed on the flow path connecting the valve 214 and the rear clutch release valve 244 to perform a buffering role when the hydraulic pressure is supplied to the rear clutch C1.

However, in the hydraulic control system as described above, since all friction elements except for the rear clutch are controlled by the first pressure control valve, the coupling clutch and the release clutch are controlled by the first pressure control valve during shifting. As a result, it is difficult to precisely control the quality variation or the temperature due to the dependence of the dependent structure by the mechanical orifice.

In addition, the hydraulic pressure supplied to the front clutch among the friction elements operating at three speeds is controlled by the first pressure control valve and supplied through a 2-3 / 4-3 shift valve controlled by the three-speed pipeline hydraulic pressure of the shift control valve. In addition, there is a problem that the shifting speed is reduced and the 1 ↔ 3 speed skipping shift is impossible.

Therefore, the present invention has been invented to solve the above-mentioned conventional problems, and an object of the present invention is to facilitate the shift control by allowing the coupling side clutch and the release side clutch to be independently controlled during 2 → 3 and 4 → 3 shifts. In addition, the present invention provides a hydraulic control system of an automatic transmission for a vehicle that improves a feeling of shifting and enables a 1 ↔ 3 speed skip shift.

1 is an N-range hydraulic circuit diagram of a hydraulic control system according to the present invention.

Figure 2 is an excerpt of the main portion of the present invention.

3 is a D range 1 speed hydraulic circuit diagram of a hydraulic control system according to the present invention;

4 is a D-range 2-speed hydraulic circuit diagram of a hydraulic control system according to the present invention.

5 is a D-range three-speed hydraulic circuit diagram of the hydraulic control system according to the present invention.

Figure 6 is a D range four-speed hydraulic circuit diagram of the hydraulic control system according to the present invention.

7 is an L range hydraulic circuit diagram of a hydraulic control system according to the present invention.

8 is a hydraulic circuit diagram in the R range of the hydraulic control system according to the present invention.

9 is a hydraulic circuit diagram of a conventional hydraulic control system.

In order to realize this, the present invention converts a flow path by a shift control valve controlled by two solenoid valves, a manual valve linked to a select lever operated by a driver, and hydraulic pressure supplied from first and second pressure control valves. At the same time, these hydraulic pressures are applied to the rear clutches operating in forward 1,2,3 speeds, kick-down brakes operating in 2nd and 4th forwards, front clutches operating in 3rd forward and reverse, and 3rd and 4th forwards. And a plurality of spool valves for selectively supplying hydraulic pressure to the low-reverse brake operating in reverse,

A 2-3 / 4-3 shift valve which is controlled by three speeds and four speeds and switches the flow path so as to selectively supply the hydraulic pressure of the third speed or the second pressure control valve to the rear clutch and the front clutch;

And a 4-3 shift valve for supplying the hydraulic pressure supplied from the 2-3 / 4-3 shift valve to the rear clutch via the rear clutch release valve while being controlled by the operating pressure of the end clutch and the operating pressure of the front clutch. Provides a hydraulic control system of an automatic transmission for a vehicle.

Hereinafter, with reference to the accompanying drawings, preferred embodiments of the present invention that can specifically realize the above object will be described in detail.

1 is a hydraulic circuit diagram of a hydraulic control system according to the present invention. The torque converter 2 receives power from an engine and converts torque to a transmission side, and an oil pump 4 is required for the torque converter and the shift stage control. It generates and discharges oil and oil necessary for lubrication.

The oil pressure generated from the oil pump 4 includes a pressure regulating valve 6 which makes the oil pressure constant, a torque converter control valve 8 which constantly adjusts the torque converter and lubrication oil pressure, and a power of the torque converter. It is supplied to a damper clutch control valve 10 to increase the transmission efficiency.

In addition, a part of the oil generated from the oil pump 4 is a manual valve for switching the flow path while interlocking with the reducing valve 12 and the selector lever in the driver's seat to keep the pressure always lower than the line pressure. The constant hydraulic pressure supplied to the valve 14 and reduced in the reducing valve 12 is supplied to the control pressure of the first pressure control valve 16 and the second pressure control valve 18.

A part of the hydraulic pressure supplied to the first and second pressure control valves 16 and 18 is supplied to the NR control valve 20 which reduces shift shock when the mode is changed from the neutral range to the reverse range. When 14 is in the travel (D) range, the hydraulic passage flows through the channel 22 under the action of the first solenoid valve S1 and the second solenoid valve S2 controlled on / off by the transmission control unit. The switching shift control valve 24 communicates with each other to achieve manual and automatic shift control together with the manual valve 14 described above.

In addition, a first-speed pipe line 26 is branched on the pipe line 22 to supply line pressure to the first and second pressure control valves 16 and 18, and the first and second pressure control valves 16 are provided. 18, the flow path is switched by the control pressure of the third and fourth solenoid valves S3 and S4.

As described above, the control pressure of the first pressure control valve 16 among the pressure control valves controlled by the third and fourth solenoid valves S3 and S4 branches through the 1-2 shift valve 28 so that a part of the pressure is low. Supplied to reverse brake C5, partly branched back from control switch valve 30, partly to end clutch C3, and partly to kickdown brake C2 via failsafe valve 32 Supplied.

The control pressure of the second pressure control valve 18 is controlled by the rear clutch via the 2-3 / 4-3 shift valve 34, the 4-3 shift valve 36, and the rear clutch release valve 38. It is supplied to C1), the accumulator (AC) is disposed on the conduit connecting the 4-3 shift valve 36 and the rear clutch release valve 48 to cushion the hydraulic pressure flowing through the flow path thereof.

The shift control valve 24 is connected to the second speed line 40, the third speed line 42, and the fourth speed line 44. The second speed line 40 controls the 1-2 shift valve 28. Simultaneously with the supply of pressure, the operating pressure of the kick-down brake C2 is supplied through the control switch valve 30 and the fail-safe valve 32.

The third speed pipe 42 supplies the control pressure of the 2-3 / 4-3 shift valve 34 and optionally the rear clutch C1 via the 2-3 / 4-3 shift valve 34. The supply pressure is supplied, and some of the hydraulic pressure is supplied to the end clutch C3 via the end clutch valve 46 and the control switch valve 30.

In addition, the four-speed pipeline 44 supplies the control pressure of the rear clutch release valve 38 and is supplied to the pressure regulating valve 6 at the fourth forward speed through the high-low pressure valve 48 to regulate the line pressure. Done.

The manual valve 14 is connected to the timing control conduit 50 and uses hydraulic pressure flowing along the conduit as the control pressure of the control switch valve 30 and the high-low pressure valve 48. Controlled by a fifth solenoid valve S5 disposed on 50.

When the manual valve 6 is in the reverse R range, the hydraulic pressure supplied to the reverse first control pipe line 52 is supplied to the control pressure of the rear clutch release valve 38 and at the same time, a 2-3 / 4-3 shift valve. Through 34 is supplied to the release side chamber of the front clutch C4, the kick-down servo C2, and the control pressure of the fail-safe valve 32.

The hydraulic pressure supplied to the reverse second control conduit 54 is passed to the low-reverse brake C5 acting as a reaction element at the reverse shift stage via the 1-2 shift valve 28 through the NR control valve 20. Supplied.

The 2-3 / 4-3 shift valve 34 is selectively controlled to supply the hydraulic pressure of the third speed control valve or the second pressure control valve 18 to the rear clutch C1 and the front clutch C4 while being controlled by the third speed pressure. Done.

Further, the 4-3 shift valve 36 controls the hydraulic pressure supplied from the 2-3 / 4-3 shift valve 34 while being controlled by the operating pressure of the end clutch C3 and the operating pressure of the front clutch C4. It is supplied to the rear clutch C1 via the rear clutch release valve 38.

Accordingly, the 2-3 / 4-3 shift valve 34 includes a first port 60 to receive a control pressure at a third speed and a second port 62 to receive a reverse pressure as shown in FIGS. 1 and 2. And the third port 64 supplied with the hydraulic pressure from the second pressure control valve 18, the fourth port 66 supplied with the third speed pressure, and the hydraulic pressure supplied to the second port 62. The fourth port 68 for supplying hydraulic pressure to the release chamber of the brake C2 and the front clutch C4, and the hydraulic pressure supplied to the third and fourth ports 64 and 66 are supplied to the 4-3 shift valve ( A valve body including a sixth port 70 to be supplied to 36 and a seventh port 72 to be supplied at four speed pressures through the rear clutch release valve 38 are provided.

The valve spool embedded in the valve body connects the first land 74 acting by the control pressure of the first port 60 and the third port 64 to the fifth port 68 selectively. A second land 76 and a third land 78 that selectively connects the fourth port 66 to the sixth port 70. 80) is burnt.

In addition, the 4-3 shift valve 36 is a first port 82 to receive the end clutch operating pressure as a control pressure, and a second to receive hydraulic pressure from the 2-3 / 4-3 shift valve 34. The port 84, the third port 86 which receives the operating pressure of the front clutch C4 as the control pressure, and the hydraulic pressure supplied to the second port 84 are rearward through the rear clutch release valve 38. A valve body including a fourth port 88 for supplying the clutch C1 is retained.

The valve spool embedded in the valve body includes a first land 90 acting on a control pressure supplied to the first port 90, and second and fourth ports 84 together with the first land 90. And a second land 92 which selectively connects the 88 to each other, and a spring 94 is supported on the second land 92.

According to the hydraulic control system of the present invention as described above, as shown in FIG. 3, the shift is performed while the rear clutch C1 is operated and controlled at the first forward speed, and at the second forward speed, as shown in FIG. 4, the rear clutch C1 and The shift is performed while the kick-down brake C2 is operated and controlled.

In the third forward speed, the shift is performed while the rear clutch C1, the end clutch C3, and the front clutch C4 are operated and controlled, as shown in FIG. The shift is made while the end clutch C3 is operated and controlled.

Further, in the L range, the shift is performed while the rear clutch C1 and the low-reverse brake C5 are operated as in FIG. 7, and in the reverse shift stage, the front clutch C4 and the low-reverse are as shown in FIG. 8. The shift is made while the brake C5 is operated and controlled.

Due to the change of the flow path of the 2-3 / 4-3 shift valve 34 and the addition of the 4-3 shift valve 36 in the above-described shifting process, when shifting from 2 to 3 speeds, as shown in FIG. As the valve spool of the 2-3 / 4-3 shift valve 34 moves to the right in the drawing due to the high pressure, the control pressure of the second pressure control valve 18 is released to the release side chamber and the front clutch of the kick-down brake C2. It is supplied at the working pressure of (C4).

The rear clutch C1, which is supplied with the control pressure of the second pressure control valve 18 in the forward 1,2, is converted to the third speed pressure.

In addition, at the time of 3 → 4 shifting, as shown in FIG. 6, the fourth speed pressure is supplied at the control pressure of the 2-3 / 4-3 shift valve 34, whereby the valve of the 2-3 / 4-3 shift valve 34 is provided. While the spool moves to the left in the figure, it blocks the third speed pressure supplied to the 4-3 shift valve 36 and supplies the pressure of the second pressure control valve 18, but due to the operating pressure of the end clutch C3, The valve spool of the shift valve 36 moves to the left to block the hydraulic pressure supplied to the rear clutch C1.

Then, the operating pressure supplied to the rear clutch C1 is discharged through the discharge port of the rear clutch release valve 38 by the port change of the rear clutch release valve 38 by the four speed pressure, and the shift to the fourth speed is completed. .

At the time of 4 → 3 shifting, the valve spool of the 2-3 / 4-3 shift valve 34 moves to the right in the drawing by the 3 speed pressure as shown in FIGS. 5 and 6 while the second pressure control valve 18 The control pressure is supplied to the operating pressure of the release chamber of the kick-down brake C2 and the front clutch C4, and the rear clutch C1 is operated while being supplied with the third speed pressure.

At this time, the rear clutch C1 is end clutch C3 supplied at the control pressure of the 4-3 shift valve 34 even though the port switching of the 2-3 / 4-3 shift valve 34 is performed and the third speed pressure is supplied. Since the flow path is formed only when the working pressure of the release is made later than the operation of the front clutch (C4).

As described above, according to the hydraulic control system of the present invention, the control of the second pressure control valve 18 is not subordinated by one first pressure control valve 16 in a 2 → 3, 4 → 3 shifting process. By independent control by pressure and 3,4 speed pressure, precise control is possible, and the mechanical subordinate structure by the orifice can be avoided, and the shifting feeling can be greatly improved.

In addition, since the front clutch C4 is capable of independent control from the rear clutch C1 and the end clutch C4, it is possible to perform a skip shift of 1 → 3, 3 → 1.

That is, by operating the front clutch C4 independently so that all the friction elements except the rear clutch C1 are controlled by the control pressure of the first pressure control valve, it is operated at each shift stage. Independent control is achieved without the friction elements being released dependent.

As described above, according to the present invention, it is possible to independently control the hydraulic pressure supplied to the release chamber and the front clutch of the kick-down brake at the third forward speed, thereby greatly improving the shifting feeling during the shift of 2 → 3, 4 → 3. , 1 → 3, 3 → 1 is the invention to enable the skip shift.

Claims (3)

The hydraulic pressure supplied from the first and second pressure control valves and the manual valve linked to the selector lever operated by the driver, the shift control valve controlled by the two solenoid valves, and the pressure control valves are moved forward. Rear clutches operating in 2 and 3 speeds, kick-down brakes operating in 2nd and 4th forwards, front clutches operating in 3rd and 4th forwards, end clutches operating in 3rd and 4th forwards, and reverse Including a plurality of spool valve to selectively supply hydraulic pressure to the low-reverse brake operating in A 2-3 / 4-3 shift valve which is controlled by three speeds and four speeds and switches the flow path so as to selectively supply the hydraulic pressure of the third speed or the second pressure control valve to the rear clutch and the front clutch; And a 4-3 shift valve for supplying the hydraulic pressure supplied from the 2-3 / 4-3 shift valve to the rear clutch via the rear clutch release valve while being controlled by the operating pressure of the end clutch and the operating pressure of the front clutch. Hydraulic control system of the automatic transmission for a vehicle, characterized in that made. The shift valve according to claim 1, wherein the 2-3 / 4-3 shift valve includes a first port receiving a control pressure at a third speed, a second port supplied with a reverse pressure, and a second hydraulic pressure supplied from the second pressure control valve. A third port, a fourth port supplied with three speed pressures, a fifth port for supplying hydraulic pressure to the release chamber of the kick-down brake and the front clutch, and the third and fourth ports. A valve body having a sixth port for supplying supplied hydraulic pressure to the 4-3 shift valve and a seventh port for receiving four-speed pressure through the rear clutch release valve; A first land acting by the control pressure of the first port, a second land selectively connecting the third port to the fifth port, and a second link selectively connecting the fourth port to the sixth port. Consists of three lands, the third land comprises a valve spool spring is carried, characterized in that the hydraulic control system for an automatic transmission for a vehicle. The 4-3 shift valve according to claim 1, wherein the 4-3 shift valve includes a first port supplied with the end clutch operating pressure as a control pressure, a second port supplied with hydraulic pressure from the 2-3 / 4-3 shift valve, and a front clutch. A valve body having a third port for receiving an operating pressure as a control pressure and a fourth port for supplying hydraulic pressure supplied to the second port to the rear clutch through a rear clutch release valve; And a first land acting on the control pressure supplied to the first port, and a second land selectively connecting the second and fourth ports together with the first land, wherein the spring is provided in the second land. Hydraulic control system for an automatic transmission for a vehicle, characterized in that it comprises a valve spool that is supported.