JPH03186624A - Hydraulic clutch control device - Google Patents

Abstract

PURPOSE:To reduce the load of a bearing by disposing, in a first circuit, a valve for controlling the hydraulic pressure of a second circuit and a valve for setting the pressure in a clutch cover to a predetermined pressure, and by providing a cut-off valve for reducing this hydraulic pressure in association with an increase in cylinder hydraulic pressure. CONSTITUTION:An oil pump 900 is connected thereto with first and second circuits 110, 120, and a first pressure control solenoid valve 130 controls the hydraulic pressure of the second circuit communicated with a cylinder 10. Further, a back pressure valve 140 sets the hydraulic pressure in a clutch cover 1 to a predetermined constant value. A second pressure control solenoid valve 150 for feeding and discharging hydraulic oil to and from the cylinder 10 controls the engagement of a clutch. When this hydraulic pressure increases, hydraulic pressure is led from a pipe line 400 to a cut-off valve 500 which is therefore opened to decrease the pressure in the clutch cover. Accordingly, the thrust force acting upon the transmission side is decreased, thereby it is possible to reduce the load of a bearing.

Description

DETAILED DESCRIPTION OF THE INVENTION <Field of Industrial Application> The present invention relates to a control device for a hydraulic clutch of an automobile.

<Conventional technology> A clutch disc mounted on the input shaft of a flywheel fixed to the engine's crankshaft is pressed in the direction of clutch engagement by a hydraulically actuated piston mounted on the back of the flywheel, and the spring force A hydraulic clutch in which a clutch disc is biased in the direction of clutch disengagement is known, for example, from Japanese Utility Model Application No. 59-88524.

In the above-mentioned hydraulic clutch, a hydraulically actuated piston is used to engage the clutch, but a spring is used to disengage the clutch, so there is a problem in the responsiveness of clutch engagement and disengagement.

Further, the above-mentioned hydraulic clutch is a so-called dry type, and requires measures to prevent wear of the clutch disk, which is repeatedly and severely pressed by a hydraulic piston.

In order to improve these problems, the inside of the clutch cover in which the clutch disc and hydraulic piston are installed is sealed, and oil at a predetermined pressure supplied from an oil pump is circulated within this sealed space. A hydraulic clutch is provided in which pressure oil always acts on a hydraulic piston in a backward direction to disengage the clutch, and a hydraulic pressure higher than the oil pressure in the sealed space is applied to the hydraulic piston to connect the clutch. .

<Problems to be Solved by the Invention> In the wet hydraulic clutch in which the latch cover is filled with pressure oil as described above, the lubricating action of the clutch disk by the pressure oil and the clutch... However, the pressure oil inside the clutch cover applies thrust force to the clutch cover ffi engine and transmission sides, which causes unnecessary load on the bearings on the engine and transmission sides. There is.

Means for Solving the Problems The present invention has been made to solve the above-mentioned problems, and its characteristic configuration is that a clutch is installed in a clutch cover connected to the engine crankshaft. In a hydraulic clutch that includes a disc and a piston that presses the clutch disc in the clutch engagement direction, and in which pressure oil that presses the piston in the clutch disengagement direction is constantly circulated and supplied in the clutch cover, the oil in the oil tank is The oil pump includes an oil pump that sucks and discharges oil, a first circuit that communicates with the discharge side of the oil pump and a pressure oil supply side into the clutch cover, and a second circuit that communicates with the cylinder of the piston. A first pressure control solenoid valve that controls the rise and fall of the pressure in the circuit and a back pressure valve that controls the pressure oil pc2 supplied into the clutch cover to a constant pressure are provided, and a discharge circuit for the pressure oil pc2 supplied into the clutch cover is provided. , directing pressure oil pcl to the cylinder of the piston;
A cut-off valve is provided to reduce the pressure of the pressure oil pc2 from the set value of the back pressure valve in accordance with the pressure increase of the pressure oil pc1.

Effect〉 With the above configuration, clutch pressing is performed using pressure, that is, pressure oil p.
As the pressure of cI increases, the internal pressure inside the clutch cover, that is, the pressure of pressure oil pc2, is reduced by the operation of the cut-off valve below the pressure set by the back pressure valve, and a thrust force is applied to the engine side or transmission side of the clutch cover. This reduces the

<Example of actual tumor> Examples of the present invention will be described below based on the drawings. FIG. 1 shows the overall structure of a hydraulic clutch, where l is an engine crankshaft, 2 is an input shaft, and a clutch disc 3 is connected to the input shaft 2 by splines. 6 is a clutch cover disposed on the input shaft 2 in a sealed manner. The clutch disc 3 is inside this clutch cover 6.
is arranged, and a piston 11 for pressing the clutch disc 3 against the clutch cover 6 is provided. 10 is a cylinder that slidably holds the piston 11, and 12 is a rotation preventing member that allows the piston 11 to slide and restricts the rotation direction.

4 is a flex plate fixed to the crankshaft 1; A ring galley connected to the stator motor is attached to its outer diameter end. A ring gear 7 for power transmission is fixed to the flex plate 4, and a ring gear 8 that meshes with the ring gear 7 is fixed to the outer surface of the clutch cover 6.

13 is an oil pump, and 14 is a control pulp.

The control valve 14 includes a boat 16 that supplies pressure oil gc1 to the back chamber of the piston 11 via an oil passage 15;
Pressure oil pc2 is introduced into the space 17 in the clutch cover 6 through the oil passage 18.
It has a boat 19 for supplying pressure oil through the space 17, and a boat 20 for returning the pressure oil PC2 in the space 17 to the oil pump 13 through the gap between the front surface of the piston 11 and the clutch disc 3.

The present invention is a device for controlling the hydraulic clutch configured as described above, and its configuration will be explained with reference to FIG. 2. 80 is an oil tank, and a filter 180 is installed inside the oil tank.

Reference numeral 900 denotes an oil pump corresponding to the variable displacement oil pump 13, and its suction [9a and the oil tank 80 are connected through a conduit 190. Further, a first circuit 110 communicating with the boat 19 of the hydraulic clutch and a second circuit 120 communicating with the boat 16 are branched and connected to the discharge 1*9b of the oil pump 900.

The first circuit 110 includes a first pressure control solenoid valve 130 that controls the rise and fall of the pressure in the second circuit 120, and a space inside the clutch cover 1 between the first pressure control solenoid valve 130 and the boat 19. A back pressure valve 140 is provided for controlling the constantly supplied pressure oil PC2 to a constant pressure. 200
is a conduit connecting the first circuit 110 and the conduit 190 via the back pressure valve 140.

On the other hand, the second circuit 120 is provided with a second pressure control solenoid valve 150 that controls the supply and discharge of pressure oil PC1 to and from the cylinder 10 of the piston 11.

Incidentally, all of the pressure oil discharged from the 1.2 pressure control solenoid valves 130 and 150 and the back pressure valve 140 is returned to the oil tank 80.

In addition, the space 17 inside the clutch cover 1 and the oil tank 8
It is connected to the filter 180 inside 0 through a discharge pipe 160, and an oil cooler 170 is installed in the discharge pipe 160. A cut-off valve 500 is provided in the discharge pipe 160 in front of the oil cooler 170, and a signal pressure oil is supplied to the cut-off valve 500 from the supply line 300 connecting the second pressure solenoid control valve 150 and the boat 16. A conduit 400 is connected thereto for guiding the air. This cut-off valve 500 is closed by a spring when the pressure oil pc1 is at a low pressure, and opens as the pressure of the pressure oil pc1 increases.

Next, the operation of the above configuration will be explained. oil pump 9
Since 00 is a variable displacement type, the eccentricity of the cam ring 93 is controlled in proportion to the flow rate of pressure oil by the piston 90 of the cylinder 92, which adjusts the eccentricity of the cam ring 93, so that the flow rate is constant regardless of fluctuations in the rotation speed. Discharges pressurized oil.

The first pressure control solenoid valve 130 is normally wide open,
The pressure oil discharged from the oil pump 900 flows into the first circuit 110 and is controlled to a constant pressure by the back pressure valve 140. Pressure oil PC2 controlled to this constant pressure is supplied from the boat 19 into the space 17 and moves the piston 11. Press in the direction of clutch disengagement.

Then, the pressure oil PC2 in the space 17 is returned to the oil tank 80 via the pipe line 160.

That is, the hydraulic clutch uses pressure oil P passing through the first circuit 110.
C2 always biases the clutch into the disengaged state.

Therefore, the pressure is applied to the first pressure control solenoid valve 130 and the second pressure control solenoid valve 150, and the first pressure control solenoid valve 130 performs a throttle operation to increase the pressure of the pressure oil PC1 to the second circuit 120. The pressure increase of this pressure oil PC1 is controlled to be higher than that of pressure oil PC2. The second pressure control solenoid valve 150 is
Supplying pressure oil PC1 to the boat 16 according to the applied electromagnetic value,
The clutch is controlled to be connected slowly or quickly depending on the driving condition, etc.

When the clutch is released from the connected state, the second pressure control mTh magnetic valve 150 is switched to discharge the pressure oil Pct supplied to the cylinder 10 into the oil tank 80.

Therefore, when the pressure oil pc1 is at a low pressure (clutch disengaged), the cutoff valve 500 closes the discharge circuit of the pressure oil pc2 by the force of the spring, and the internal pressure in the space 17 in the clutch cover 1 is maintained at a constant level set by the back pressure valve 140. Holds pressure. However, as the pressure of the pressure oil pcl increases, the cutoff valve 500 opens the discharge circuit of the pressure oil pc2 due to the pressure oil pc1 guided from the pipe line 400 to the cutoff valve 500, and as shown in FIG. Control the pressure of pc2 to decrease. As a result, the internal pressure in the space 17 inside the clutch cover 1 is reduced to the back pressure valve 14.
This value is lower than the set value of 0, thereby reducing the thrust force of the clutch cover l toward the engine or transmission side.

<Effects of the Invention> As described above, according to the present invention, as the pressure of the clutch press increases, that is, the pressure of the pressure oil pc1 increases, the internal pressure in the clutch cover, that is, the pressure of the pressure oil pc2, is transferred to the discharge circuit of the pressure oil pc2. Since the provided cut-off valve is operated using the pressure oil PC1 as a signal pressure to reduce the pressure, the thrust force of the clutch cover toward the engine side or the transmission side is reduced, and the bearings on the engine side and the transmission side are reduced. Ensure durability.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a hydraulic clutch, FIG. 2 is a circuit diagram of a control device of the present invention, and FIG. 3 is a pressure oil control characteristic diagram of the present invention. 3...Kuraguchi disc, 6...Clutch cover 1
1...Piston, 17...Space, 110...1st
Circuit, 1? O...-second circuit, 130... first pressure control solenoid valve, 140... back pressure valve, 150... second pressure control solenoid valve, 160... discharge pipe, 400... pipe Road, 500...Cutoff valve. Patent applicant Hino Automatic Book Industry Co., Ltd. Agent Hirai Yu E.,.

Claims (1)

[Claims] A clutch cover connected to the engine crankshaft includes a clutch disc and a piston that presses the clutch disc in the direction of clutch engagement, and pressurized oil is constantly supplied within the clutch cover to press the piston in the direction of clutch disengagement. In a hydraulic clutch that circulates and supplies oil, there is an oil pump that sucks and discharges oil from an oil tank, a first circuit that communicates with the discharge side of this oil pump and a pressure oil supply side into the clutch cover, and a first circuit that communicates with the cylinder of the piston. a first pressure control solenoid valve for controlling the pressure in the second circuit to rise and fall; and a back pressure valve for controlling pressure oil pc2 supplied into the clutch cover to a constant pressure; The second circuit is provided with a second pressure control solenoid valve that controls the supply and discharge of pressure oil pc1 to the cylinder of the piston, and the second pressure control solenoid valve controls the supply and discharge of pressure oil pc1 to the cylinder of the piston.
Pressure oil pc to the cylinder of the piston is supplied to the discharge circuit of No. 2.
1, and in response to the pressure rise of this pressure oil pc1, the pressure oil pc
A control device for a hydraulic clutch, characterized in that a cut-off valve is provided to reduce the pressure of No. 2 from a set value of the back pressure valve.