JPH0538249Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a clutch cover assembly with a diaphragm spring.

(Prior art) In this type of clutch cover assembly,
There is a great demand for longer lifespans of clutches in taxis, commercial vehicles, etc. One example of an attempt to extend clutch life is to increase the effective working thickness of the facings by securing the facings to the clutch disk without the use of rivets or the like.

However, a general clutch cover assembly has a structure as shown in FIG. 7, for example, and the wear-in distance D is secured by the load characteristics as shown in FIG. 8. However, since there is a limit to the width of the wear-in allowance D, when the amount of wear on the facing 6 increases, the pressing load changes from the initial set position Ps, passes a peak (an increase in pedal force), and then gradually decreases. Finally, as the diaphragm spring 8 tilts significantly toward the pressure plate, the pressing load becomes insufficient and slippage occurs, making it impossible to utilize the facing 6 to its maximum wear amount.

In order to extend the life of the facing and stabilize the pressing load by increasing the wear-in distance, the applicant of the present application has proposed, for example, in JP-A-63-270925 that the height of the fulcrum is automatically adjusted as the facing wears. We are proposing a clutch cover assembly that can increase the That is, the fulcrum that contacts the diaphragm spring is divided into two inner and outer Fulcrum rings, and as the facing wears, the action of the slide key and spring automatically pushes the Fulcrum ring toward the diaphragm spring. ing.

However, there are many parts and assembly is time consuming, and since the slide key is fitted to the pressure plate so that it can move in the radial direction, centrifugal force due to clutch rotation affects the Fulcrum ring. It may push up too much, making it difficult to adjust the weight of the Fulcrum ring and slide key.

(Purpose of the invention) The present invention aims to extend the life of the clutch and stabilize its performance by automatically maintaining the initial set load in accordance with the amount of wear on the facing, and also to reduce the number of parts. It is intended to be.

(Technical means for achieving the object) In order to achieve the above object, the present invention arranges inner and outer Fulcrum rings around the outer periphery of the support thread formed on the pressure plate,
Both Fulcrum rings have supporting points that contact the diaphragm spring spaced apart from each other in the radial direction, and a stepped portion that restricts the height of the outer supporting point from being higher than the inner supporting point. The height of the inner fulcrum is increased by rotating the inner peripheral thread of the inner fulcrum ring in the direction opposite to the direction of clutch rotation relative to the pressure plate. The inner peripheral thread of the outer Fulcrum ring is rotated in the direction opposite to the direction of clutch rotation relative to the inner Fulcrum ring. In order to increase the height of the fulcrum of the outer Fulcrum ring, each Fulcrum ring is screwed onto the outer peripheral thread of the inner Fulcrum ring, and each Fulcrum A ratchet mechanism is provided that allows the ram ring to rotate relative to the pressure plate only in the direction of rotation in which the fulcrum of the ram ring becomes higher.

(Embodiment) FIG. 1 is a longitudinal cross-sectional view of a clutch cover assembly to which the present invention is applied, in which a clutch cover 2 is fixed to the rear surface of a flywheel 1 on the input side and extends axially forward. clutch cover 2
A facing 6 of a clutch disk 3, a pressure plate 7, and a diaphragm spring 8 are arranged between the front end wall of the clutch disk 3 and the flywheel 1 in this order from the flywheel 1 side (rear side). The diaphragm spring 8 is held between two wire rings 9, and the wire rings 9 are connected to a plurality of stud pins 10.
The stud pin 10 is fixed to the end wall of the clutch cover 2. Although not shown, the inner peripheral end of the diaphragm spring 8 faces a release bearing, and the release action of the release bearing causes the outer peripheral end of the diaphragm spring 8 to move forward with the wire ring 9 as a pivot point. There is.

The pressure plate 7 has a plurality of outer peripheral protrusions 20
The protrusion 20 is connected to the clutch cover 2 via a strap plate 21 so as to be movable in the axial direction. pressure plate 7
An annular support portion 7a that protrudes forward is provided on the front surface of the
An inner fulcrum ring 14 having an inner fulcrum part 23 at the front end is disposed on the outer peripheral surface side of the support part 7a, and An outer Fulcrum ring 15 having an outer fulcrum portion 24 at its front end is arranged.

A support screw portion 1 is provided on the outer peripheral surface of the support portion 7a.
1 is formed, and an inner peripheral threaded part 26 is formed on the inner peripheral surface of the inner Fulcrum ring 14 to be screwed into the support threaded part 11, and these threaded parts 11, 2
6 is configured to move the inner fulcrum ring 14 rearward by rotating the inner fulcrum ring 14 relative to the pressure plate 7 in the clutch rotation direction R side.
In other words, by rotating the inner fulcrum ring 14 relative to the pressure plate 7 in the clutch rotation direction R side and the opposite direction N side, the inner fulcrum ring 14 moves forward and inward. The height of the fulcrum portion 23 is increased.

An outer circumferential threaded portion 27 is formed on the outer circumferential surface of the inner Fulcrum ring 14, and an outer circumferential threaded portion 27 is formed on the inner circumferential surface of the outer Fulcrum ring 15.
An inner circumferential threaded portion 28 is formed to be screwed into the outer circumferential threaded portion 27 of No. 4, and these threaded portions 27 and 28 rotate the outer fulcrum ring 15 toward the clutch rotation direction R side with respect to the inner fulcrum ring 14. The outer Fulcrum ring 15 is configured to be moved rearward by relative rotation. In other words, by rotating the outer Fulcrum ring 15 relative to the inner Fulcrum ring 14 in the clutch rotation direction R side and the opposite direction N side, the outer Fulcrum ring 15 moves forward. The height of the outer fulcrum portion 24 is increased.

The annular fulcrum portions 23 and 24 of both Fulcrum rings 14 and 15 are formed so as to be spaced apart from each other by a small distance in the radial direction. In addition, step portions 18 and 19 are formed in the fitting portion between both Fulcrum rings 14 and 15, and both step portions 18 and 19 are opposed to each other.
Inner Fulcrum ring 1 due to contact between 8 and 19
4 to prevent the outer Fulcrum ring 15 from shifting forward, and both fulcrum parts 23, 2
4 are maintained in substantially the same vertical plane.

Between each Fulcrum ring 14, 15 and the pressure plate 7, each Fulcrum ring 1
A ratchet mechanism 29 that allows rotation relative to the pressure plate 7 only in the direction of rotation in which the fulcrum portions 23 and 24 of 4 and 15 become higher, that is, in the N side.
30 are provided respectively. Each ratchet mechanism 29, 30 engages with inner and outer annular ratchet teeth 31, 32 formed on the front surface of the pressure plate 7 as shown in FIG. It consists of ratchet pawls 37 and 38 fixed to rings 14 and 15.

To explain the structure of the inner ratchet mechanism 29 in detail, an annular recess 35 is formed on the rear end surface of the inner fulcrum ring 14, and a rivet 45 is attached to the bottom of the annular recess 35 to attach a leaf spring material to the ratchet, as shown in FIG. A claw 37 is fixed. The free end of the ratchet pawl 37 is inclined so as to be rearward as it goes toward the rotation direction R side, and the free end portion of the ratchet pawl 37
1 is engaged. The inner ratchet pawl 37 is the fourth
As shown in the figure, a plurality of them are arranged at equal intervals in the rotation direction. In addition, in the portions of the annular recess 35 corresponding to the respective ratchet claws 37, insertion holes 39 are formed for inserting a jig for pressing the ratchet claws 37 against the bottom side of the recess 35 when the Fulcrum ring is attached. ing.

The outer ratchet mechanism 30 shown in FIG. 1 has a similar structure to the inner ratchet mechanism 29, and the outer ratchet pawl 38 made of a leaf spring material is fixed to the bottom of the annular recess 36 of the outer fulcrum ring 15 with a rivet. There is. The free end of the ratchet pawl 37 is inclined toward the rear in the direction of rotation R, and engages with the outer ratchet tooth 32.
Further, in the portions of the annular recess 36 corresponding to the respective ratchet pawls 38, insertion holes are inserted for inserting a jig for holding the ratchet pawls 38 against the bottom side of the recess 36 when the Fulcrum ring is attached, as shown in FIG. Hole 3
9a are formed respectively.

Explain the operation. FIG. 1 shows an initial set state, for example, the peak position Ps' shown in FIG. 8 is set. When the release is operated in the initial state shown in FIG. 1, the pressure plate 7 moves forward due to the reaction force of the strut plate 21.
Although the diaphragm spring 8 is tilted so that the outer peripheral end is on the front side, the outer fulcrum ring 15 is not pushed forward due to the engagement of the stepped portions 18 and 19, and both fulcrum portions 23 and 24 are substantially the same. It remains aligned in the vertical plane.

FIG. 5 shows the state when the facing 6 is worn out due to use, that is, when it is worn-in.
Since the diaphragm spring 8 is inclined so that its outer peripheral end is rearward, it is supported only by the fulcrum part 24 of the outer fulcrum ring 15, and the fulcrum part 23 of the inner fulcrum ring 14 and the diaphragm spring 8 are supported by the fulcrum part 24 of the outer fulcrum ring 15. There will be a gap between them. In other words, the inner fulcrum ring 14 is free to rotate relative to the pressure plate 7, so it receives changes in engine speed as an external force, and the inner fulcrum ring 14 is pressed due to the amount of inertia. It rotates in the rotational direction R and the opposite direction N relative to the shear plate 7, thereby moving the inner supporting point 23 forward until it comes into contact with the diaphragm spring 8 and becomes higher. At that time, the stepped portions 18, 19
A gap C is created between them.

When the release operation is performed from the state shown in FIG. 5, the outer peripheral end of the diaphragm spring 8 moves forward as shown in FIG.
A gap is created between the diaphragm spring 8 and the diaphragm spring 8. That is, since the outer fulcrum ring 15 is in a free state in which it can rotate relative to the pressure plate 7 and the inner fulcrum 23, it receives changes in engine speed as an external force, and due to its inertia, the outer fulcrum ring 15 is rotated freely. The aluminium ring 15 rotates in the rotational direction R and the opposite direction N relative to the pressure plate 7 and the inner aluminium ring 14, so that the outer fulcrum 24 is pushed forward. , filling the gap C (FIG. 5), and filling the stepped portion 18,
It is locked by the engagement of 19.

That is, at the time of wear-in, both fulcrum portions 23 and 24 automatically move forward (increase in height) by an amount corresponding to the amount of wear on the facing 6 by the release operation, thereby returning the set state of the diaphragm spring 8 to its initial state.

(Effects of the invention) As explained above, according to the invention: (1) Just by performing a normal release operation during wear-in, the rotational force of the engine can be changed, the screw connection and the ratchet mechanism 29, 30 can be used. By the relative rotation of the ram rings 14 and 15, the heights of the fulcrum portions 23 and 24 can be automatically increased according to the amount of wear on the facing 6.

Therefore, the facing can be fully used up to its wear limit without any maintenance, the period until clutch replacement can be extended, and the life of the clutch can be improved.

(2) Since the fulcrum portions 23 and 24 are automatically raised in accordance with the amount of wear on the facing 6, the set load can always be kept at a constant value during the period of use.

That is, by setting the set load at the peak of the load characteristics at the time of assembly, the same set load can always be maintained as at the time of assembly, regardless of wear of the facing, and the torque transmission performance of the clutch does not change.

(3) Since the fulcrum parts 23 and 24 are automatically raised in accordance with the amount of wear on the facing 6, the attitude (inclination) of the diaphragm spring 8 does not change when the clutch is connected, and the release characteristics do not change. .

Therefore, the camera can always be released using the same release operation.

(4) The inner Fulcrum ring 14 is screwed to the pressure plate 7, the outer Fulcrum ring 15 is screwed to the inner Fulcrum ring 14, and both Fulcrum rings 14,1
Since only the ratchet mechanisms 29 and 30 are provided between the 5 and the pressure plate 7, the number of parts can be reduced compared to, for example, a case where a slide key, a spring for pushing up, etc. are provided.

[Brief explanation of the drawing]

Figure 1 is a vertical sectional view showing the initial set state of the clutch cover assembly to which the present invention is applied, Figure 2 is an enlarged partial cross-sectional view of Figure 1, and Figure 3 is the pressure plate of Figure 2. arrow view, 4th
The figure is an arrow view of the Fulcrum ring in Fig. 2, Fig. 5 is a longitudinal cross-sectional view showing the state when worn in, and Fig. 6 is a longitudinal sectional view showing the condition when worn in.
The figure is a longitudinal sectional view showing the release state during wear-in, FIG. 7 is a longitudinal sectional view of a conventional example, and FIG. 8 is a load characteristic diagram. 6... Facing, 7... Pressure plate, 8... Diaphragm spring,
11...Support thread part, 14...Inner Fulcrum ring, 15...Outer Fulcrum ring,
23...Inner fulcrum part, 24...Outer fulcrum part, 26
...Inner circumference threaded part, 27...Outer circumference threaded part, 28...
Inner circumference threaded portion, 29, 30... Ratchet mechanism.

Claims (1)

[Scope of utility model registration request] Inner and outer Fulcrum rings are placed around the outer periphery of the support thread formed on the pressure plate, and both Fulcrum rings have supporting points that contact the diaphragm springs, spaced apart from each other in the radial direction. At the same time, a stepped portion is formed to prevent the outer fulcrum from being higher than the inner fulcrum, and the inner circumferential threaded portion of the inner Fulcrum ring is placed inwardly with respect to the pressure plate. The inner peripheral thread of the outer Fulcrum ring is screwed onto the support thread so that the height of the inner fulcrum becomes higher when the Fulcrum ring rotates in the opposite direction to the clutch rotation direction. , the inner Fulcrum ring is rotated in a direction opposite to the clutch rotation direction relative to the inner Fulcrum ring, so that the fulcrum height of the outer Fulcrum ring becomes higher. It is screwed into the outer circumferential thread, and between each Fulcrum ring and the pressure plate, the rotation relative to the pressure plate is limited only in the direction of rotation in which the fulcrum of each Fulcrum ring becomes higher. A clutch cover assembly characterized by being provided with a latch mechanism that allows the clutch to move freely.