JPH0480250B2 - - Google Patents

Description

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

<Prior Art> Hydraulic clutches for automatically controlling automobile clutches using hydraulic piston mechanisms are well known.

Since this hydraulic piston mechanism is installed inside the clutch body, rotation of the clutch causes centrifugal force to act on the oil in the hydraulic chamber of the hydraulic piston mechanism, and the piston is pushed in the direction of clutch engagement by the centrifugal force of the oil. However, there is a problem of poor clutch disengagement.

In order to eliminate the adverse effects caused by the centrifugal force of oil, for example, Japanese Patent Application Laid-open No. 106725/1983 has been proposed.

<Problems to be Solved by the Invention> The above-mentioned Japanese Patent Application Laid-open No. 59-106725 discloses that a reaction force body is fitted onto the input shaft of a transmission so as to be movable in the axial direction, and a clutch is attached to the front surface of this reaction force body. A piston in contact with a pressing body that presses a plate against a flywheel is provided to form a displacement chamber, a chamber is formed on the rear surface of the reaction force body, and a counter piston integral with the pressing body is disposed, and a counter piston is disposed integrally with the pressing body. Both chambers are always filled with the same working fluid, and the hydraulic pressure due to the centrifugal force generated in the displacement chamber is balanced with the hydraulic pressure due to the centrifugal force generated in the chamber.

In this case, the hydraulic actuation mechanism is provided on the clutch cover side, and includes a reaction body, a pressing body, a counter piston, a spring and a pin that apply force to the reaction body in the axial direction, and a spring and pin that apply force to the reaction body in the axial direction. The two sleeves that control the hydraulic passage, the spring and pin that are interposed between the counter piston and the flywheel are essential parts of the clutch, and as a result, the structure is complex and the entire clutch is large. In addition to increasing the size and weight, there are also problems in that it takes time to process and assemble due to the large number of parts, which increases costs.

The purpose of the present invention is to solve such problems and provide a hydraulic clutch that eliminates the influence of centrifugal force of oil. <Means for Solving the Problems> The characteristic configuration includes a flywheel fixed to the end of the engine crankshaft, a clutch cover attached to the flywheel, and a transmission input interposed between the flywheel and the clutch cover. The clutch disk connected to the shaft and the front and rear end surfaces provided on the outer periphery of the flywheel so as to be movable in the axial direction to press the clutch disk against the clutch cover have approximately the same pressure receiving area, and are similar to the flywheel. A concentric ring-shaped piston, hydraulic chambers with substantially equal volumes at the front and rear of the piston to move the piston forward and backward, and pressure oil supplied to the front and rear hydraulic chambers provided in the flywheel and input shaft. It is equipped with two hydraulic passages for discharging hydraulic pressure, and a directional switching valve connected to these two hydraulic passages for supplying and discharging hydraulic pressure to both of the hydraulic chambers.

<Operation> With the above configuration, by supplying pressure oil to the rear hydraulic chamber provided in the flywheel, the hydraulic piston moves forward and presses the clutch disc against the clutch cover to bring the clutch into a connected state, and the oil is supplied to the rear hydraulic chamber. When the engine rotates at high speeds where centrifugal force acts, pressure oil is also introduced into the front hydraulic chamber, and the front and rear hydraulic pressure is maintained even if the hydraulic pressure fluctuates due to centrifugal force due to the piston having approximately equal pressure receiving areas on the front and rear end faces and the front and rear hydraulic chambers having approximately equal volume. This ensures that the piston is balanced in the chamber and suppresses the forward action of the piston pressing against the clutch disc.

<Examples> Examples of the present invention will be described below based on the drawings. In FIG. 1, 1 is a crankshaft of an engine, 2 is a flywheel fixed to one end of the crankshaft with bolts 5, and 15 is a clutch cover attached to the flywheel 2. A clutch disk 9 connected to the input shaft 6 of the transmission is interposed between the flywheel 2 and the clutch cover 15. 10 is a pressure plate that is in contact with the clutch disk 9.

In the present invention, the flywheel 2 is provided at a position corresponding to the clutch disk 9 of the flywheel 2.
A concentric annular hydraulic cylinder 3 is provided in the axial direction, and a piston 4 whose front and rear end surfaces have substantially equal pressure receiving areas is fitted in the hydraulic cylinder 3 so as to be movable forward and backward,
The piston 4 makes the volumes of the hydraulic cylinder 3 substantially equal to the rear hydraulic chamber 11a and the front hydraulic chamber 11.
b.

The flywheel 2 also includes the rear hydraulic chamber 1.
1a, and a front hydraulic chamber passage 8b, which communicates with the front hydraulic chamber 11b, are provided within the shaft of the input shaft 6, and which communicate with the rear hydraulic chamber passage 8a. The first passage 7a
A second passage 7b is provided which communicates with the front hydraulic chamber passage 8b.

The first and second passages 7a and 7b are connected to a hydraulic pump 14 which is interlocked with the flywheel 2 through gears, and a switching valve 12 which supplies and discharges hydraulic pressure to the rear hydraulic chamber 11a and the front hydraulic chamber 11b. ing. This switching valve 12 supplies hydraulic pressure to the rear hydraulic chamber 11a,
First port 13 for discharging the hydraulic pressure from the front hydraulic chamber 11b
a, a second port 13b that supplies hydraulic pressure to the rear hydraulic chamber 11a and the front hydraulic chamber 11b, and the front hydraulic chamber 11b.
and a third port 13c that supplies hydraulic pressure to the rear hydraulic chamber 11a and discharges hydraulic pressure from the rear hydraulic chamber 11a.

FIG. 2 shows another embodiment of the invention. In this other embodiment, a cover plate 16 is attached to the flywheel 2 on the front end side of the piston 4 to form a front hydraulic chamber 11b, and a sealing material is applied to the outer peripheral surface of the cover plate 16 from the front end side of the piston 4. A connecting member 17 is provided which extends slidably and closely through the connecting member 17, and the connecting member 17 and the pressure plate 10 are connected with bolts.The other structure is substantially the same as that in FIG. The same is true.

Since the present invention has the above-described structure, normally the switching valve 12 is switched to supply pressure oil to the rear hydraulic chamber 11a to move the piston 4 forward, and the piston 4 is moved forward via the pressure plate 10 to the clutch disk. 9 to the clutch cover 1 integrated with the flywheel 2
5 to connect the clutch.

Further, by discharging the pressure oil supplied to the rear hydraulic chamber 11a by switching the switching valve 12, the pressing force of the piston 4 against the clutch disc 9 is reduced, and the clutch disc 9 and the clutch cover 15 are caused to slip. The clutch then cuts off the transmission of rotational power and enters a so-called clutch disengaged state.

Therefore, it is also possible to control the clutch into a half-clutch state by controlling the discharge amount of the pressure oil supplied to the rear hydraulic chamber 11a.

Therefore, when pressurized oil is supplied to the rear hydraulic chamber 11a and the clutch is connected, when the engine rotates at high speed and a large centrifugal force acts on the flywheel 2, the switching valve 12 also supplies pressurized oil to the front hydraulic chamber 11b. Pressure oil is supplied to the front hydraulic chamber 11b. As a result, even if the pressure of the pressure oil in the rear hydraulic chamber 11a and the front hydraulic chamber 11b increases due to centrifugal force, the pressure receiving area of both end surfaces of the piston 4 and the volumes of the rear hydraulic chamber 11a and the front hydraulic chamber 11b are approximately equal. Because of the relationship, the piston 4 is balanced in the pressed state with the clutch connected, and the piston 4
inhibits forward movement. As a result, fluctuations in the transmission torque of the clutch due to changes in engine rotational speed are prevented, the clutch disengages well at high engine rotational speeds, and delicate automatic control of half-clutching is facilitated.

<Effects of the Invention> As described above, in the present invention for eliminating the adverse effects caused by the centrifugal force of oil in a hydraulic clutch, a ring-shaped piston for pressing the clutch disk against the clutch cover is attached to the outer circumference of the flywheel in the axial direction. The piston is provided so as to be movable forward and backward, the pressure receiving areas of the front and rear end surfaces of the piston are approximately equal, and in order to move the piston forward and backward, hydraulic chambers having approximately equal volumes are formed at the front and rear of the piston, and the flywheel and input shaft are connected to each other. Since the structure includes a hydraulic passage for supplying and discharging pressure oil to the front and rear hydraulic chambers, the number of component parts is significantly smaller than that of the conventional clutch, and the structure is simple, and the overall shape of the clutch is reduced. This has the advantage that the performance of the hydraulic clutch can be improved without increasing the size or weight of the clutch, and it can be provided at low cost.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a main part of the present invention, and FIG. 2 is a sectional view of a main part showing another embodiment of the invention. 1... Crankshaft, 2... Flywheel, 3... Hydraulic cylinder, 4... Piston, 8a
... Rear hydraulic chamber passage, 8b... Front hydraulic chamber passage,
9...Clutch disk, 11a...Rear hydraulic chamber,
11b... Front hydraulic chamber, 16... Lid plate, 17... Connecting member.

Claims (1)

[Claims] 1 A flywheel fixed to the end of the crankshaft of the engine, a clutch cover attached to the flywheel, and a clutch interposed between the flywheel and the clutch cover and coupled to the input shaft of the transmission. A disk and a ring-shaped ring concentrically with the flywheel have substantially equal pressure receiving areas on the front and rear end surfaces provided on the outer circumference of the flywheel so as to be movable in the axial direction in order to press the clutch disk against the clutch cover. A piston, hydraulic chambers having substantially equal volumes at the front and rear of the piston for moving the piston forward and backward, and two hydraulic chambers provided in the flywheel and input shaft for supplying and discharging pressure oil to the front and rear hydraulic chambers. 1. A hydraulic clutch comprising: two hydraulic passages; and a directional control valve connected to the two hydraulic passages and supplying and discharging hydraulic pressure to both hydraulic chambers.