JP2616201B2 - Lock-up clutch control device - Google Patents

Description

The present invention relates to a lock-up clutch control device.

(B) Conventional technology A conventional lock-up clutch control device is disclosed in Japanese Patent Publication No. 2-9225. A lock-up clutch piston for connecting or releasing the cover member integrated with the pump impeller and the turbine runner so as to rotate integrally is provided in the torque converter shown therein. A pump impeller on the apply chamber side, which is one chamber defined by the lock-up clutch piston,
A turbine runner and a stator are arranged, and an apply chamber supply oil path for supplying oil pressure to the apply chamber and an apply chamber discharge oil path for discharging oil pressure from the apply chamber are provided. A release chamber supply / discharge passage is connected to a release chamber, which is the other chamber defined by the lock-up clutch piston. The oil pressure is always supplied from the supply chamber supply oil passage to the apply chamber, and the oil pressure is constantly discharged from the apply chamber discharge oil passage to maintain the application chamber at a predetermined oil pressure. When the lock-up clutch piston is released, the release chamber is supplied with oil pressure higher than the oil pressure of the apply chamber from the oil supply / drain passage of the release chamber.When the clutch is engaged, the oil pressure in the release chamber is discharged. An oil pressure slightly lower than the oil pressure is supplied.

(C) Problems to be Solved by the Invention However, such a conventional lock-up clutch control device has a problem that a sufficient transmission torque capacity cannot be obtained when the lock-up clutch is completely engaged. That is, the transmission torque capacity of the lock-up clutch changes according to the pressing force from the apply chamber to the release chamber. If the oil pressure in the release chamber is 0, it changes according to the oil pressure in the apply chamber. In the Apply room,
Oil pressure is supplied from the supply chamber supply oil passage and discharged from the apply chamber discharge oil passage, and the oil is always flowing. The effective oil pressure acting on the lock-up clutch piston in the apply chamber is lower than the oil pressure in the supply chamber supply oil passage and higher than the oil pressure in the apply chamber discharge oil passage, that is, an intermediate value between the oil pressures in both oil passages. . As described above, since the oil pressure in the supply chamber supply oil passage does not directly act on the lock-up clutch piston, a sufficient transmission torque capacity of the lock-up clutch cannot be obtained. An object of the present invention is to solve such a problem.

(D) Means for Solving the Problems The present invention solves the above problems by closing the apply chamber discharge oil passage when the lock-up clutch is fully engaged. That is, in the fluid transmission device (50) targeted by the present invention, the cover member (60) integral with the pump impeller (52) and the turbine runner (54) are connected or released so as to rotate integrally. An lock chamber (82) is provided with a lock-up clutch piston (58), and is one chamber defined by the lock-up clutch piston.
A pump impeller and a turbine runner are arranged on the side, and an oil supply passage (9) for supplying oil pressure to the apply chamber is provided.
2) and an apply chamber discharge oil passage (94) for discharging hydraulic pressure from the apply chamber. A release chamber supply / discharge passage is provided in the release chamber (80), which is the other chamber defined by the lock-up clutch piston. (83) is connected.
The lock-up control valve (10) supplies oil pressure from the supply chamber supply oil passage to the apply chamber when the lock-up clutch piston is released and half-clutch control, and discharges the oil pressure from the apply chamber discharge oil passage to divide the apply chamber into a predetermined state. The release chamber is configured to supply a hydraulic pressure equal to or higher than the hydraulic pressure of the apply chamber or slightly lower than the hydraulic pressure of the apply chamber to the release chamber from the supply / discharge oil passage of the release chamber. Assuming such a configuration, the lock-up control valve according to the present invention supplies the hydraulic pressure to the apply chamber from the supply chamber supply oil path and closes the apply chamber discharge oil path when the lock-up clutch is completely engaged, and closes the release chamber. It is characterized in that the oil pressure is discharged through a supply / discharge oil passage of a release chamber. In addition, the code | symbol in a parenthesis shows the corresponding member of the Example mentioned later.

(E) Operation During lock-up clutch piston release and half-clutch control, oil flows through the apply chamber as in the conventional case. When the lock-up clutch piston is completely engaged, the hydraulic pressure in the release chamber is discharged and the oil discharge passage in the apply chamber is closed. Therefore, the flow of the oil passing through the apply chamber is stopped, and the hydraulic pressure of the supply chamber supply oil passage acts on the apply chamber as it is. Since the lock-up clutch piston is pressed by the high oil pressure in the apply chamber, the transmission torque capacity when the lock-up clutch piston is completely engaged can be increased.

(F) Embodiment FIG. 1 shows an embodiment. The torque converter 50, which is a fluid transmission device with a lock-up mechanism, has a pump impeller 5
2. It has a turbine runner 54, a stator 56 and a lock-up clutch piston 58. The pump impeller 52 is welded to the cover shell 60, and the two form a casing of the torque converter 50. Stator 56
Are supported by a stator shaft 64 via a one-way clutch 66. The hub 68 of the turbine runner 54 is a shaft
It is connected by a spline so as to rotate integrally with 70. A lock-up clutch piston 58 is arranged between the turbine runner 54 and the cover shell 60. The inner diameter of the lock-up clutch piston 58 is supported by the shaft of the hub 68 so as to be movable in the axial direction. The lock-up clutch piston 58 and the turbine runner 54 are connected via a spring 74 so as to transmit a radial force. Cover shell 60 of lock-up clutch piston 58
A facing 76 is adhered to the outer peripheral surface on the side facing the surface. The interior of the torque converter 50 is divided into two chambers by the lock-up clutch piston 58, that is, the cover shell 60.
It is divided into a release chamber 80 on the side and an apply chamber 82 on the opposite side. The release chamber 80 communicates with a release chamber oil supply / discharge passage 83 formed by an axial hole provided at the center of the shaft 70. On the other hand, the apply chamber 82 is in communication with an apply chamber supply oil passage 92 formed by an annular portion between the inner diameter of the converter sleeve 91 integrated with the pump impeller 52 and the outer diameter of the stator shaft 64, and Through a hole penetrating the inner and outer diameters of the stator shaft 64, it also communicates with an apply chamber discharge oil passage 94 formed by an annular portion formed between the inner diameter portion of the stator shaft 64 and the outer diameter portion of the shaft 70. I have.

The lock-up control valve 10 for controlling the oil pressure in the release chamber 80 and the apply chamber 82 has a spool 12 having three lands 12a, 12b and 12c, and a spring 14 for pushing the spool 12 rightward in FIG. ing. Spool 12 is port 16
It is axially movably fitted within a valve bore having a, 16b, 16c, 16d, 16e, 16f and 16g. The port 16a is connected to the oil passage 18. The oil passage 18 is connected via an orifice 22 to an oil passage 20 to which a constant pressure is always supplied. The oil pressure in the oil passage 18 can be controlled by a solenoid 24. That is, the solenoid 24 can adjust the oil pressure of the oil passage 18 by controlling the open / close state of the orifice 26 provided so that the oil pressure of the oil passage 18 can be discharged. The port 16b is a drain port. The port 16c is connected to the release chamber oil supply / discharge passage 83 described above. The port 16d is connected to the supply chamber supply oil passage 92 described above and is also connected to the oil passage 28 to which the torque converter supply pressure is always supplied. port
16e is drained through cooler 30. Port 16f
Is connected to the aforementioned application chamber discharge oil passage 94. Port 16g is connected to port 16c.

Next, the operation of this embodiment will be described. When the lock-up clutch piston 58 is released, hydraulic pressure is supplied as follows. That is, the solenoid 24 closes the orifice 26 to bring the oil pressure in the oil passage 18 to the highest state. Therefore, the spool 12 is at the position shown in the lower half of FIG. 1, and the port 16c communicates with the port 16d, and the port 16e communicates with the port 16f. Therefore, the torque converter supply pressure is supplied from the port 16c to the release chamber 80 via the release chamber supply / discharge oil passage 83. On the other hand, the hydraulic pressure supplied from the supply chamber supply oil passage 92 to the apply chamber 82 is
Discharge through 94, port 16f, port 16e and cooler 30. As a result, the oil pressure in the release chamber 80 becomes higher than the oil pressure in the apply chamber 82, and the lock-up clutch piston
58 is released.

When performing the half-clutch control, the duty ratio of the solenoid 24 is controlled, and the hydraulic pressure of the port 16a is controlled to a predetermined state lower than the constant pressure of the oil passage 20. Because of this, the spool
12 moves slightly to the right from the position shown in the lower half of FIG. 1, and transfers a part of the oil supplied from port 16d to port 16b.
And the oil pressure at port 16c is fed back to port 16g.
And the pressure is adjusted according to the oil pressure. This regulated port
The hydraulic pressure of 16c is supplied to the release chamber 80. Therefore,
When the pressure adjustment value of the port 16c is slightly lower than the oil pressure of the apply chamber 82, the lock-up clutch piston 58
Becomes a half clutch state.

Next, when the lock-up clutch piston 58 is completely engaged, the orifice 26 is released to make the oil pressure in the oil passage 18 the lowest. As a result, the spool 12 becomes the first
In the position shown in the upper half in the figure, the port 16b communicates with the port 16c, and the port 16f is closed by the land 12c. As a result, the hydraulic pressure from the oil passage 28 is supplied to the apply chamber 82, but the port 16 communicating with the apply chamber discharge oil passage 94
Since the state f is shut off, the oil in the apply chamber 82 is not discharged, and the flow of the oil stops. That is, the oil pressure in the apply chamber 82 is the same as the oil pressure in the apply chamber supply oil passage 92. On the other hand, the hydraulic pressure of the release chamber 80 is drained via the release chamber supply / discharge passage 83, the port 16c, and the port 16b. Therefore, the lock-up clutch piston 58 is pressed against the cover shell 60 by the high oil pressure on the apply chamber 82 side, and a large transmission torque capacity can be obtained.

(G) Effect of the Invention As described above, according to the present invention, when the lock-up clutch piston is completely engaged, the oil flow passage in the apply chamber is closed to stop the flow of oil in the apply chamber. As a result, the hydraulic pressure in the apply chamber increases, and the transmission torque capacity of the lock-up clutch can be increased.

[Brief description of the drawings]

FIG. 1 is a diagram showing an embodiment of the present invention. 10: Lock-up control valve, 50: Torque converter (fluid transmission), 52: Pump impeller, 54: Turbine runner, 58: Lock-up clutch piston, 60
... cover member, 80 ... release chamber, 82 ... apply chamber, 83 ... release chamber supply / discharge oil path, 92 ... apply chamber supply oil path, 94 ... apply chamber discharge oil path.

Claims (1)

(57) [Claims] A lockup clutch piston for connecting or releasing a cover member integral with a pump impeller and a turbine runner so as to rotate integrally therewith is provided in the fluid transmission, and the lockup clutch piston is partitioned by the lockup clutch piston. A pump impeller and a turbine runner are disposed on the apply chamber side, which is one of the chambers, and an apply chamber supply oil path for supplying oil pressure to the apply chamber and an apply chamber discharge oil path for discharging oil pressure from the apply chamber are provided. The release chamber supply / discharge oil passage is connected to the release chamber, which is the other chamber partitioned by the lock-up clutch piston, and is used to release the lock-up clutch piston and control the half-clutch from the supply chamber supply oil passage. Supply hydraulic pressure to the apply chamber and discharge oil pressure from the A lock-up control that maintains the interior of the room at a predetermined oil pressure and supplies the release room with a hydraulic pressure that is higher than the hydraulic pressure of the apply chamber or slightly lower than the hydraulic pressure of the apply chamber from the oil supply / drain passage of the release chamber. In a lock-up clutch control device having a valve, the lock-up control valve supplies hydraulic pressure to the apply chamber from the apply chamber supply oil path and closes the apply chamber discharge oil path when the lock-up clutch piston is fully engaged,
A lock-up clutch control device configured to discharge a hydraulic pressure of a release chamber through a release chamber oil supply / discharge passage.