JP6014875B2 - Hydraulic control device for automatic transmission - Google Patents

Description

  The present invention relates to a hydraulic control device for an automatic transmission mounted on a vehicle, and more particularly to a device for controlling the hydraulic pressure of a friction element that is fastened during a reverse shift.

  A hydraulic control device for this type of automatic transmission is disclosed in Patent Document 1, for example. In the hydraulic control device for an automatic transmission disclosed in the literature 1, a sequence valve and a B2 pressure control valve are operated in order to suppress an engagement shock of a friction element (B2 brake) during reverse shift. In these valves, the B2 pressure control valve and the B2 brake are communicated with each other by switching the sequence valve to the reverse shift transient state (the state where the spool is in the right position in FIG. 3 of the same document 1). The hydraulic pressure adjusted so as to rise relatively gently by the control valve is supplied to the B2 brake, thereby suppressing the engagement shock of the friction element. After the B2 brake is engaged, the sequence valve is switched to the reverse shift completed state (the state where the spool is in the left position in FIG. 3 of the document 1), and the line pressure is supplied to the B2 brake. When the B2 brake is engaged, the third solenoid valve is de-energized and the hydraulic pressure supply from the B2 pressure control valve is stopped.

Japanese Patent No. 3387811

  By the way, when the reverse shift is performed, if the sequence valve sticks in a reverse shift transient state due to some cause (for example, influence of chips remaining in the valve body), the B2 brake is supplied from the B2 pressure control valve. Although the engagement is temporarily performed by the applied hydraulic pressure, the hydraulic pressure supply from the B2 pressure control valve is promptly stopped after the engagement, so that the engagement state returns to the release state again. As a result, the shift state becomes a neutral state, and the vehicle cannot travel in reverse.

  The present invention has been made in view of such a problem, and even if a reverse control valve (sequence valve) sticks in a reverse shift transient state, the vehicle is supplied with hydraulic pressure to a friction element to be fastened at the time of reverse shift. It is an object of the present invention to provide a hydraulic control device for an automatic transmission that can reverse-drive a vehicle.

  The hydraulic control device for an automatic transmission according to the present invention, when a reverse shift operation is performed, the hydraulic pressure adjusted by the hydraulic control valve with respect to the friction element to be engaged is passed through the reverse control valve in the reverse shift transient state. On the assumption that the reverse control valve is switched to the reverse shift completion state and a constant hydraulic pressure is supplied to the friction element when it is determined that the friction element is substantially engaged. And a stick determination means for determining that the reverse control valve has stuck in a reverse shift transient state, and when the means determines that the reverse control valve has stuck in a reverse shift transient state, Hydraulic supply restarting means for restarting the supply of the hydraulic pressure regulated by the hydraulic control valve. It is.

  According to the hydraulic control device for an automatic transmission having such a configuration, when the reverse control valve is stuck in the reverse shift transient state, the supply of hydraulic pressure to the friction element to be engaged is temporarily stopped and then restarted. Can do reverse running.

  According to the present invention, even if the reverse control valve sticks in a reverse shift transient state, the vehicle can be driven in reverse.

It is a figure which shows schematic structure of the automatic transmission in embodiment of this invention. 4 is an operation table showing whether each friction element of the automatic transmission according to the embodiment of the present invention is in an engaged state or an unengaged state at each shift stage. It is a figure which shows the hydraulic control system of the automatic transmission in embodiment of this invention.

  A hydraulic control device for an automatic transmission according to an embodiment of the present invention will be described below with reference to the drawings. As shown in FIG. 1, the automatic transmission according to the present embodiment includes a torque converter 1, an input shaft 2 to which engine power is transmitted via the torque converter 1, three clutches C1 to C3, two brakes B1, B2, the one-way clutch F, the Ravigneaux type planetary gear mechanism 4, the output gear 5, the output shaft 7, and the differential gear 8 are provided.

  The forward sun gear 4a and the input shaft 2 of the planetary gear mechanism 4 are connected via a C1 clutch, and the rear sun gear 4b and the input shaft 2 are connected via a C2 clutch. The carrier 4c is connected to the intermediate shaft 3, and the intermediate shaft 3 is connected to the input shaft 2 via a C3 clutch. The carrier 4c is connected to the transmission case 6 via a B2 brake and a one-way clutch F that allows only forward rotation (in the engine rotation direction) of the carrier 4c. The carrier 4c supports two types of pinion gears 4d and 4e, the forward sun gear 4a meshes with a long pinion 4d having a long shaft length, and the rear sun gear 4b meshes with the long pinion 4d via a short pinion 4e having a short shaft length. . A ring gear 4f that meshes only with the long pinion 4d is coupled to the output gear 5. The output gear 5 is connected to the differential device 8 via the output shaft 7.

  The automatic transmission realizes four forward speeds and one reverse speed as shown in FIG. 2 by operating the clutches C1, C2, C3, the brakes B1, B2 and the one-way clutch F. In FIG. 2, ● represents the action state of hydraulic pressure. The B2 brake is engaged at the time of reverse and the first speed, but is engaged at the first speed only in the L range (indicated by a broken line circle in FIG. 2).

  FIG. 3 shows a part of the hydraulic control device used in the automatic transmission (main part according to the embodiment of the present invention). 10 is an oil pump, 11 is a regulator valve, 12 is a manual valve, 13 is a reverse control valve, 14 is a B2 pressure control bubble (hydraulic control valve), 15 is a first solenoid valve, 16 is a second solenoid valve, and 17 is an ECU. It is.

  The regulator valve 11 adjusts the discharge pressure of the oil pump 10 to a predetermined line pressure PL. The regulated line pressure PL is supplied to the manual valve 12, the B2 pressure control valve 14, the first and second solenoid valves 15 and 16, and other valves (not shown).

  In the manual valve 12, the spool 12a is switched to each of the L, 2, D, N, R, and P ranges according to manual operation of the shift lever. The line pressure PL input from the input port 12b of the manual bubble 12 is selectively output from the forward output port 12c or the reverse output port 12d. The oil passages and valves connected to the forward output port 12c are not shown.

  As shown in FIG. 3, the reverse control valve 13 switches the oil passage when the spool 13b moves to the right position or the left position. The reverse control valve 13 includes a spool 13b urged to the left by a spring 13a. The signal pressure of the first solenoid valve 15 is input to the right end signal port 13c, the predetermined pressure is supplied to the left end ports 13d and 13i, and the hydraulic pressure adjusted from the B2 pressure control valve 14 is supplied to the port 13e. Supplied. The port 13g communicates with the B2 brake, and the line pressure is supplied to the ports 13h and 13f. In the figure, “EX” is a drain port.

  The B2 pressure control valve 14 is a valve for adjusting the line pressure PL and supplying it to the B2 brake. The B2 pressure control valve 14 includes a spool 14b urged to the left by a spring 14a. A signal pressure is input from the second solenoid valve 16 to the port 14c. The port 14 e communicates with the port 13 e of the reverse control valve 13. Line pressure is supplied to the port 14f. In the figure, “EX” is a drain port.

  The first solenoid valve 15 turns on / off the signal pressure input to the signal port 13 c of the reverse control valve 13 in accordance with a command from the ECU 17. As the first solenoid valve 15, an ON / OFF switching valve can be used.

  The second solenoid valve 16 outputs a signal pressure to the B2 pressure control valve 14 in accordance with a command from the ECU 17. Since the second solenoid valve 16 is required to perform delicate hydraulic control, a duty control valve or a linear solenoid valve is used.

  When the shift range is P, N, etc., no signal pressure is input from the first solenoid valve 15 to the signal port 13c, and the reverse control valve 13 is in a state where the spool 13b is in the right position. The second solenoid valve 16 turns off the signal pressure, and the B2 pressure control valve 14 is in a state where the spool 14b is in the left position. In this case, the port 13g and the port 13e of the reverse control valve 13 do not communicate with each other, and the port 14f of the B2 pressure control bubble 14 is closed, so that hydraulic pressure is supplied from the B2 pressure control bubble 14 to the port 13e of the reverse control valve 13. No hydraulic pressure is supplied to the B2 brake. Further, when the shift range is P, N, etc., no line pressure is supplied from the reverse output port 12d of the manual valve 12, and therefore no hydraulic pressure is supplied to the C1 clutch.

  When the shift range is switched from P, N, etc. to the R range (that is, when a reverse shift operation is performed), line pressure is supplied from the reverse output port 12d of the manual valve 12 to the C1 clutch, and the C1 clutch is engaged.

  Further, since the first solenoid valve 15 inputs a signal pressure to the signal port 13c of the reverse control valve 13, the reverse control valve 13 is in a state where the spool 13b is in the left position (reverse shift transient state). Further, when the second solenoid valve 16 inputs the signal pressure to the B2 pressure control valve 14, the B2 pressure control valve 14 supplies the hydraulic pressure adjusted so as to rise gently to the port 13 e of the reverse control valve 13. The regulated hydraulic pressure is supplied to the B2 brake through the port 13e and the port 13g of the reverse control valve 13, and the B2 brake is gradually engaged or substantially engaged (the brake slippage is a predetermined percentage or less).

  When the ECU 17 detects the engaged state or the substantially engaged state of the B2 brake, the first solenoid valve 15 is turned off. As a result, the signal pressure input to the port 13c of the reverse control valve 13 is stopped, so that the spool 13b is moved to the right side (reverse shift completed state) by the hydraulic pressure supplied to the port 13d. The port 13h and the port 13g communicate with each other, and a line pressure (an original pressure of a constant hydraulic pressure) is supplied to the B2 brake. Further, the second solenoid valve 16 is turned off to stop the output of the signal pressure, and the B2 pressure control valve 14 stops the supply of hydraulic pressure to the port 13e of the reverse control valve 13.

  However, if for some reason the spool 13b of the reverse control valve 13 is stuck (fixed) at the left position and cannot move to the right, the shift range is switched from P, N, etc. to the R range, the ECU 17 Even if the first solenoid valve 15 is turned OFF after detecting the brake engagement state or the substantially engagement state, the spool 13b does not move in the left position, and the line pressure is not supplied to the B2 brake. Further, since the B2 pressure control valve 14 stops the supply of the hydraulic pressure to the port 13e of the reverse control valve 13, the hydraulic pressure is not supplied from anywhere to the B2 brake, and the B2 brake once engaged or substantially engaged is released again, and the engine rotation The number suddenly rises.

  However, when the ECU 17 detects that the turbine rotational speed has exceeded a predetermined value (for example, 3000 rpm) even though the output rotational speed is not greater than a predetermined value (for example, 100 rpm), the reverse control valve 13 performs reverse shift. It is determined that the stick is made in a transient state. When the ECU 17 makes this determination, it outputs a signal pressure to the second solenoid valve 16, restarts the supply of the hydraulic pressure regulated by the B2 pressure control valve 14, and reverse control valve sticking in the reverse shift transient state. The hydraulic pressure is supplied to the B2 brake through the 13 ports 13e and 13g. As a result, the B2 brake changes from the released state to the engaged state, and the vehicle can reverse travel.

  Thus, according to the hydraulic control device for an automatic transmission according to the embodiment of the present invention, even if the reverse control valve 13 is stuck in the reverse shift transient state, the hydraulic pressure is supplied to the B2 brake, and the vehicle runs in reverse. It can be carried out.

  The present invention can be suitably applied as, for example, a hydraulic control device for an automatic transmission of an automobile.

13 Reverse control valve 14 B2 pressure control valve (hydraulic control valve)
15 1st solenoid valve 16 2nd solenoid valve 17 ECU
B2 Brake (Friction element)

Claims (1)

When a reverse shift operation is performed, the hydraulic pressure adjusted by the hydraulic control valve with respect to the friction element to be engaged is supplied to the friction element via the reverse control valve in a reverse shift transient state, and the friction element In the hydraulic control device for an automatic transmission that switches the reverse control valve to a reverse shift completed state and determines that a constant hydraulic pressure is supplied to the friction element when it is determined that it is substantially engaged.
Stick determination means for determining that the reverse control valve has stuck in a reverse shift transient state;
When the means determines that the reverse control valve has stuck in a reverse shift transient state, hydraulic supply restarting means for restarting the supply of the hydraulic pressure regulated by the hydraulic control valve to the friction element;
A hydraulic control device for an automatic transmission, comprising:

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