JPH0746820Y2 - Hydraulic operating clutch - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulically operated clutch provided between an engine and a transmission in an automobile.

[0002]

2. Description of the Related Art FIG. 3 is a side sectional view showing a conventional hydraulically operated clutch. A clutch disc 4a is connected to an input shaft 4 of a transmission (not shown).
The pressure receiving body 6 is screwed to a flywheel body 5 directly connected to an engine (not shown), and the cylinder body 5d fitted to the pressure receiving body 6 so as to be slidable in the axial direction is a flywheel body. 5, the presser plate 5a is screwed to the cylinder body 5d, and the ring-shaped piston 7 is slid in the axial direction between the pressure receiving body 6 and the cylinder body 5d. Moveable fit, which allows displacement B
And C are formed. The illustration of the pressure oil passage to each of the displacement chambers B and C is omitted.

The operation of FIG. 3 will be described below.
In a state where the flywheel body 5 directly connected to the engine is rotating and the rotation of the input shaft 4 in the transmission is stopped, the pressure oil is supplied to the displacement chamber B to displace the displacement chamber C. Is opened to a reservoir (not shown), the piston 7 pushes the pressure plate 5a to the left due to the hydraulic pressure generated in the displacement chamber B. As a result, the clutch disc 4a has the clutch surface 5e.
And pressure plate 5a for grip (gri
p) It will be done. Then, the rotational force of the flywheel body 5, that is, the output torque from the engine is changed to the clutch surface 5e.
And, the torque is transmitted from the pressure plate 5a to the clutch disc 4a, that is, the clutch is engaged, and the torque is transmitted to the input shaft 4 to start the automobile.

Contrary to the above case, the operation of disengaging the clutch opens the displacement chamber B to the reservoir and supplies the pressure oil to the displacement chamber C. Then, the hydraulic pressure generated in the displacement chamber C pushes and shifts the cylinder body 5d to the right side with respect to the pressure receiving body 6, and returns the pressure plate 5a to the right side. As a result, the clutch disc 4a and the flywheel body 5 are disengaged, and the power transmission between the engine and the drive wheels of the automobile is cut off. Further, the operation at the time of engaging or disengaging the clutch at the time of shifting the transmission is similarly performed.

In the above-mentioned operation, when the pressure plate 5a is operated, the clutch is engaged when the pressure oil is supplied to the displacement chamber B, and the pressure oil is supplied to the displacement chamber C as described above. Then, the engagement of the clutch is released. In this case, the displacement chambers B and C are
Since the flywheel body 5 rotates integrally with the flywheel body 5, the hydraulic oil in the displacement chambers B and C has a hydraulic component generated by the rotational centrifugal force. Therefore, if there is a difference in the hydraulic components generated by the rotational centrifugal force in each of the displacement chambers B and C, a disturbance will be given to the clutch engagement control.

However, in FIG. 3, the outer diameter d and the inner diameter e of the displacement chamber B match the outer diameter d and the inner diameter e of the displacement chamber C, respectively.
Therefore, the hydraulic components due to the centrifugal force generated in the two displacement chambers B and C are equal.

[0007]

[Problems to be Solved by the Invention] FIG.
In the above configuration, the hydraulic components due to the centrifugal force generated in the two displacement chambers B and C are equal. However, in order to equalize the centrifugal force components, the cylinder body 5d that slides in the axial direction and the displacement chamber C having the same size as the displacement chamber B are configured, which complicates the configuration and The result is increased weight. It is an object of the present invention to provide a hydraulically operated clutch that improves the complexity and weight of such a construction.

[0008]

SUMMARY OF THE INVENTION The present invention is a flywheel body that rotates integrally with a flywheel body that rotates integrally with an engine output shaft and is capable of sliding in the axial direction, and a flywheel thereof. -It is an improvement of the conventional clutch in which a clutch disc interlocked with the input shaft is interposed between the clutch body and the clutch surface in the axial direction. Also, the conventional clutch is a type in which the pressure plate is hydraulically operated.

The improvement is as follows. On the side opposite to the clutch disc in the axial direction of the pressure plate, a cylinder is cut in the flywheel body so as to enclose the radial direction of the input shaft, and the cylinder can slide in the axial direction. The piston is fitted to.
A pressure oil passage communicates with the first displacement chamber formed by the cylinder and the piston from the fixed portion through the flywheel body. That is, the clutch can be engaged by sending pressure oil from the pressure oil passage to the first displacement chamber, and by opening the first displacement chamber to the reservoir or the atmosphere,
The engagement is released.

Further, the flywheel body forms a chamber in which the clutch disc is enclosed and in which hydraulic oil is always present, and the chamber is communicated with the external reservoir. This means the following. When the clutch is engaged or disengaged, the piston is operated to displace the hydraulic fluid in the chamber. Therefore, the displaced hydraulic oil requires exchange of hydraulic oil with any of the spaces. In this case, the exchange is performed with an external reservoir or the like communicating with the chamber.

The first feature is that hydraulic oil is always present in the chamber. This means the following. The first displacement chamber rotates with the flywheel body that rotates integrally with the engine, so that the first displacement chamber is open to the reservoir even when the first displacement chamber is open to the reservoir. In the chamber, hydraulic pressure is generated in the hydraulic oil in the displacement chamber by the rotating centrifugal force. Further, since the chamber also rotates due to the rotation of the flywheel body, the hydraulic oil in the chamber also produces hydraulic pressure due to the rotational centrifugal force. Therefore, the force by which the piston tends to be displaced to the chamber side by the hydraulic pressure of the centrifugal force component generated in the displacement chamber and the force that tends to push the piston back by the hydraulic pressure of the centrifugal force component generated in the chamber are This has the advantage of canceling out, that is, the direction in which the hydraulic component of the rotational centrifugal force in the first displacement chamber and the hydraulic component of the rotational centrifugal force in the chamber are in equilibrium.

However, there is a clutch disk in the above chamber, which has a different rotational speed when the clutch is not engaged. Therefore, the rotating speed of the hydraulic oil in the chamber is different from the rotating speed of the displacement chamber, and the pressure balance of the rotational centrifugal force component cannot be perfectly achieved. Therefore, in the present invention, further, on the clutch disc side in the axial direction of the presser plate, a sub-piston axially opposed to the piston is fitted in the flywheel body and the first displacement is performed. The second feature is that a second displacement chamber communicating with the chamber is provided.
That is, the hydraulic pressure component of the rotational centrifugal force in the first displacement chamber cannot be balanced with the hydraulic pressure component of the rotational centrifugal force in the chamber, and the hydraulic pressure component of the rotational centrifugal force generated in the second displacement chamber is added. The counterbalanced force of the sub-piston achieves the above equilibrium.

[0013]

1 is a side sectional view of a hydraulically operated clutch according to the present invention, in which a clutch disc 1a is connected to an input shaft 1 of a transmission (not shown) and an engine (not shown) is connected. The pressure plate 2a is fitted to the spline 2m of the flywheel body 2 which is directly connected, and the shaft 2f fixed to the flywheel body 2 has the bearing member 3
The shaft 2f is rotatably and slidably fitted to the shaft 2f. Grooves 2h and 2g are formed on the circumference of the shaft 2f, and the bearing member 3 is fixed to the casing of the transmission. A piston 2c is fitted to the cylinder 2b formed in a ring shape on the flywheel body 2 so as to be slidable in the axial direction, and the first displacement chamber 2d is bored 2
e, a groove 2h cut on the circumference of the shaft 2f, and a hole 3a are connected to a hydraulic switching valve (not shown).

The chamber A enclosing the clutch disc 1a is always filled with hydraulic oil, and the chamber A communicates with the external reservoir through the perforations 2i. In the flywheel body 2, the sub-piston 2j, which sandwiches the pressure plate 2a and opposes the piston 2c, is fitted into the second displacement chamber 2k so as to be slidable in the axial direction, and the displacement chamber 2k. 2k communicates with the displacement chamber 2d. Also, the pressure plate 2
A spring 2p is provided between a and the flywheel body 2.

The operation of the above embodiment will be described below. When the transmission is set to the first speed, the hydraulic pressure switching valve is switched, and the hydraulic pressure source communicates with the perforation 3a, the pressure oil in the hydraulic pressure source passes through the perforation 3a, the groove 2h, and the perforation 2e, and the displacement chamber 2d and It is pumped to 2k. Here, the pressure receiving area of the piston 2c in the displacement chamber 2d is larger than the pressure receiving area of the sub piston 2j in the displacement chamber 2k. Therefore, even if the same hydraulic pressure is sent to both the displacement chambers 2d and 2k as described above, the pressure oil sent to the displacement chamber 2d pushes the piston 2c to the right to move the pressure plate 2a. It urges to the clutch surface 2n side. As a result, the clutch disc 1 is formed by the clutch surface 2n and the pressure plate 2a.
a is in a gripped clutch engagement state, the rotational force of the flywheel body 2, that is, the power from the engine is transmitted to the gripped clutch disc 1a and the input shaft 1, and the automobile starts. . Further, as the piston 2c moves to the right, the hydraulic oil in the chamber A is displaced, and the displaced hydraulic oil is passed through the perforations 2i, the grooves 2g and the perforations 3b to the external reservoir. -Open to Ba.

Contrary to the above operation, when the clutch is disengaged, the hydraulic pressure switching valve is switched to open the displacement chamber 2d to the reservoir, and the pressure prepress by the urging force of the spring 2p. 2a is pushed back to the left and the clutch engagement is released. The above explanation
Although the clutch engagement and disengagement at the time of starting the vehicle have been described, the same applies to the clutch engagement or disengagement operation at the time of gear shifting of the transmission.

Further, in the above operation, the spring 2p
Has a function of pushing back the pressure plate 2a when the clutch is disengaged, but even if the spring 2p is omitted, basically the clutch can be disengaged. If the displacement chamber 2d is opened to the reservoir, the pressure plate 2a will move to the clutch disc 1.
This is because a cannot be gripped and the clutch can be disengaged. However, if the pressure plate remains in contact with the clutch plate 1a when it is disengaged, a drag torque to the clutch disc 1a due to the rotation of the pressure plate 2a is generated on the transmission side, so that the transmission shifts during shifting. You will have to increase the operating force. For this reason, when it is necessary to reduce the shift operation force, the spring 2p is provided as such. Further, the spring 2p for pushing back may be pushed back by a hydraulic piston or the like.

The hydraulic operation clutch of FIG. 1 is operated as described above, but the following phenomenon occurs in the action during the operation. For example, as described above, when the vehicle starts, the clutch disc 1
a stops its rotation at the beginning of its start. Therefore, the pressure plate 2a
End face a of the clutch disc 1a and end face b of the clutch disc 1a
The distribution of the flow velocity of the hydraulic oil in the rotational circumferential direction between and is as shown in FIG. That is, the rotational circumferential flow velocity of the hydraulic oil in contact with the end surface a of the pressure plate 2a is the pressure.
The rotation speed of the plate 2a matches that of the clutch disc 1
The rotational circumferential flow velocity of the hydraulic oil in contact with the end surface b of a coincides with the stopped zero rotational speed of the clutch disc 1a.
In addition, the flow velocity distribution of the hydraulic oil between a and b changes uniformly from the state where the flow velocity of the end face b is zero toward the rotational speed of the end face a in proportion to the distance between the end faces a and b. It is ready to go.

From the above, the average flow velocity between the end face a and the end face b corresponds to 1/2 of the rotation speed of the pressure plate 2a. On the other hand, the hydraulic oil in the displacement chamber 2d is the pressure plate 2a.
It rotates at the same rotation speed as. Also, input shaft 1
The pressure increase due to the rotational centrifugal force of the hydraulic oil on the same radius from has a property proportional to the square of the rotational speed at which the hydraulic oil rotates around the input shaft 1. Therefore,
In the state where the rotation of the clutch disc 1a is stopped, the average pressure increase of the hydraulic oil between the end surfaces a and b due to the rotational centrifugal force thereof is 1 / the amount of the hydraulic pressure increase due to the rotational centrifugal force of the displacement chamber 2d. 4 (1/2 of square of the operating oil rotational speed n in the displacement chamber 2d, that is, 1/4) will increase the hydraulic pressure. Thus, when the rotational speed of the clutch disc 1a is lower than the rotational speed of the flywheel body 2, the displacement chamber 2d
There is a state in which the amount of increase in pressure due to the rotational centrifugal force at is larger than the value in the chamber A.

As described above, when the average rotational circumferential flow velocity of the hydraulic oil in the chamber A is slower than the rotational speed of the displacement chamber 2d, even if the pressure oil is not pumped into the displacement chamber 2d, as described above. If the hydraulic pressure of the rotational centrifugal force component in the displacement chamber 2d becomes larger than the hydraulic pressure of the rotational centrifugal force component in the chamber A, and assuming that the displacement chamber 2k does not exist now, the piston 2c will be urged to the right. It will be.

From the above, in the present invention, the second aspect of the present invention deals with the imbalance between the hydraulic pressure due to the rotational centrifugal force generated in the displacement chamber 2d and the hydraulic pressure due to the rotational centrifugal force generated in the chamber A. The displacement chamber 2k is provided, and the sub-piston 2j is fitted into the displacement chamber 2k. That is, even when the pressure oil is not being sent to the displacement chamber 2k, as in the displacement chamber 2d and the chamber A, the rotation centrifugal of the hydraulic oil is performed in the displacement chamber 2k by the rotation of the flywheel body 2. Oil pressure is being generated by force. Moreover, since the generated hydraulic pressure is disposed at a position farther in the radial direction than the displacement chamber 2d, the hydraulic pressure due to the rotational centrifugal force in the displacement chamber 2k becomes higher than that in the displacement chamber 2d by that amount.

In consideration of the high value of the hydraulic pressure as described above, the shortage of pressure increase due to the rotational centrifugal force generated in the chamber A is compensated for, and the rotational centrifugal force component generated in the displacement chamber 2k. The sub-piston 2j by the hydraulic pressure of
I try to push it back to the side. As a result, both the hydraulic pressure increase due to the rotational centrifugal force of the chamber A and the hydraulic pressure increase component due to the rotational centrifugal force of the displacement chamber 2k are added to the displacement chamber 2k.
The oil pressure increase component of the rotational centrifugal force at d will be canceled out.

[0023]

As is apparent from the above description, the hydraulically operated clutch according to the present invention cancels the hydraulic component due to the rotational centrifugal force with respect to the displacement chamber and the piston for hydraulically operating the displacement chamber. It is not necessary to provide an auxiliary displacement chamber C of the same size, and the rotation is made possible by simply filling the chamber A with hydraulic oil and fitting the sub piston 2j into the auxiliary small displacement chamber 2k. It is possible to almost balance the hydraulic pressure by the centrifugal force. In addition, such a small size of the auxiliary displacement chamber 2k reduces the component weight of the flywheel body 2, and the reduction in weight does not require the rotational inertia moment of the flywheel body 2. It also solves the problem of making it bigger. Further, enabling the oil pressure to be balanced by the rotational centrifugal force is achieved by the first displacement chamber 2d.
When the pressure and hydraulic pressure is automatically controlled, the disturbance due to the rotational centrifugal force component can be prevented, and the control becomes easy.

[Brief description of drawings]

FIG. 1 is a side sectional view of a hydraulically operated clutch according to the present invention.

2 is a chamber A between the end faces a and b in FIG.
3 shows the rotational velocity distribution of the working oil inside.

FIG. 3 is a side sectional view showing a conventional hydraulic operation clutch.

[Explanation of symbols]

1 input shaft, 1a clutch disc, 2 flywheel body, 2a pressure plate, 2b
Cylinder, 2c piston, 2d displacement chamber,
2e drilling, 2j sub-piston, 2k displacement chamber, 2n clutch surface, 2p spring, A
Room.

Claims (1)

[Scope of utility model registration request] 1. A pressure plate that rotates integrally with a flywheel body that rotates integrally with an engine output shaft and is slidable in the axial direction, and a clutch surface of the flywheel body. A clutch disc interlocked with the input shaft is interposed between the axial directions, and the clutch disc in the axial direction of the presser plate is provided so as to surround the radial direction of the input shaft on the side opposite to the clutch disc. A piston is fitted to the cylinder cut into the flywheel body so as to be slidable in the axial direction, and a flywheel is fixed from a fixed portion to a first displacement chamber formed by the cylinder and the piston. A first pressure oil passage communicates with the external reservoir via the valve body, and the flywheel body communicates with the external reservoir in a state of enclosing the clutch disc and in a state where hydraulic oil is always present. To form a chamber,
On the side of the clutch disc in the axial direction of the plate, a sub-piston that axially opposes the piston is fitted in the flywheel body and
A hydraulically operated clutch having a second displacement chamber communicating with the displacement chamber.