JPH0222505Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a pull-type clutch having an inertia brake that brakes rotation of an output shaft when the clutch is disengaged.

(Prior art) A concentric pressure plate is provided on the outer ring of the release bearing of a pull type clutch, and the pressure plate and the inner circumference of the clutch housing are connected to the central output shaft so as to be slidable in the center line direction. A configuration is already known in which a brake disc is arranged, a disc-shaped member is arranged on the inner peripheral side of the clutch housing of the brake disc, and a coil spring is arranged behind the disc-shaped member.
No. 47-34738, Special Publication No. 59-33771).

However, with this configuration, a cushioning effect is simply obtained by the coil spring, and it is inevitable that the inertia braking force will change significantly, and in extreme cases, there is a risk that the vehicle will stop. Therefore, skill is required to perform the operation in order to obtain an appropriate braking force. Furthermore, if the clutch is held in a disengaged state for a certain period of time, for example when the vehicle is coasting down a small slope, the friction plate tends to become hot due to the strong inertia braking force, causing the inertia brake to This may cause seizure or accelerated wear.

(Problems to be Solved by the Invention) The above-mentioned conventional configuration has a problem in that the inertia braking force varies greatly, requiring skill in operating the clutch pedal. In addition, if the clutch is held in a disengaged state for a certain period of time, the strong inertia braking force tends to cause the friction plates to become hot, which may cause the inertia brake to seize or accelerate wear. There is a problem that operation cannot be obtained.

The present invention attempts to solve the above problems.

(Means for solving the problem) The present invention is to provide a concentric pressure plate on the outer ring of the release bearing of a pull type clutch; Brake disks connected so as to be slidable in the centerline direction are arranged; a friction plate is provided on at least the inner peripheral side of the clutch housing among both sides of the brake disk; the friction plate is elastically biased from the clutch housing side. In a pull type clutch with an inertia brake that is equipped with a spring mechanism and brakes the output shaft when the clutch is disengaged; in order to increase the release stroke, the spring mechanisms are arranged symmetrically so that their inner peripheries abut each other. be done 2
It is composed of two cone springs; and is equipped with an inertia brake characterized in that the combined load of both cone springs is set to reach a maximum value approximately in the middle between the set position of both cone springs and the stroke end. It is a pull type clutch.

(Example) In FIG. 1 (arrow F points forward), the outer periphery of a clutch cover 12 is fixed to the flywheel 11 on the engine side, and the internal space formed by the flywheel 11 and the clutch cover 12 is The flywheel 1 is connected from the clutch cover 12 side by a coil spring 13 compressed in the direction of the center line.
Concentric pressure plate 14 biased toward the first side
is provided. Two clutch disks 15 are provided between the flywheel 11 and the pressure plate 14, and a pressure plate 16 is provided between the two clutch disks 15. The section is spline-fitted to the central output shaft 17. The output shaft 17 extends rearward and is rotatably supported by a transmission case 18 via a bearing 19, and is connected to a transmission gear (not shown) provided within the transmission case 18. The transmission case 18 has a clutch cover 1
2. The rear end of the clutch housing 20 that covers the clutch body including the clutch disk 15 and the like is fixed, and the front end of the clutch housing 20 is fixed to the crankcase of the engine (not shown).

A pressure plate 1 is attached to the clutch cover 12.
A support bolt 21 protruding to the 4 side is fixed, and a release lever 22 with the support bolt 21 as a fulcrum is arranged in the radial direction of the clutch. Also, by connecting the pressure plate 14 to the middle part of the release lever 22, the release lever 22
By moving the inner circumferential end of 2 in the reverse F direction, the pressure plate 14 can be forcibly moved in the reverse F direction against the spring force of the coil spring 13. . Release lever 22
The inner peripheral end of the sleeve 23 is in contact with a flange integrally formed at the front of the cylindrical sleeve 23.
3 fits into the front end of a cylindrical shaft 24 which rotatably fits into the output shaft 17, and its forward movement is restricted by a flange integrally formed at the front end of the cylindrical shaft 24. An inner ring of a release bearing 25 fits into the rear end of the cylinder shaft 24 and is fixed by a snap spring. Release bearing 2
The front part of a bearing cover 26 is fitted into the outer ring of the bearing 25, and is fixed to the outer ring of the bearing 25 by an inward flange formed at the front end of the bearing cover 26 and a snap spring. The bearing cover 26 integrally has a protrusion 27 that protrudes outward in the diametrical direction (in a direction perpendicular to the plane of the drawing), and the bifurcated tip of the yoke 28 (only one is shown) is attached to the front end surface of the protrusion 27. are in contact. York 2
The base of 8 is fitted and fixed to a support shaft 29 extending perpendicular to the plane of the paper, and the support shaft 29 is connected to a clutch pedal (not shown). Note that when the clutch pedal is depressed, the support shaft 29 rotates in the direction of arrow R.

A female thread is formed on the rear inner peripheral surface of the bearing cover 26, and a male thread of a cylindrical portion 32 formed at the front part of the pressure plate 31 is screwed into the female thread. Further, the cylindrical portion 32 is formed with a split groove 33 that is long in the center line direction and opens toward the front.
As shown in the figure, a plurality of grooves 33 (for example, six) are provided at equal intervals in the circumferential direction. On the other hand, as shown in FIG. 1, a radial internal thread is formed at the rear end of the bearing cover 26, into which a lock bolt 34 is screwed from the outer circumferential side. In the illustrated state, the tip of the lock bolt 34 protrudes inward from the bearing cover 26 and fits into the split groove 33. The pressure plate 31 has a disk shape extending in the radial direction of the clutch, and a hole formed in the center fits into the output shaft 17 with a small interval therebetween. A protrusion 35 protruding rearward is provided on the rear end surface of the pressure plate 31.
A plurality of protrusions 35 are provided at equal intervals in the circumferential direction, and the rear end surfaces of the protrusions 35 are arranged on the same plane in the clutch radial direction.

A brake case 40 located behind the pressure plate 31 is a generally cylindrical member, and its rear end is fixed to the transmission case 18 with a bolt. A groove 41 that is long in the direction of the center line is formed in the cylindrical portion formed at the front of the mission case 18, and the front end of the groove 41 is open toward the front. A plurality of split grooves 41 are provided at equal intervals in the circumferential direction, and a friction plate 42 disposed inside the brake case 40 is provided in the split grooves 41.
The outer peripheries of the two are slidably engaged in the direction of the center line.
The friction plate 42 is an annular plate member extending in the radial direction of the clutch, and a plurality of friction plates (for example, three) are arranged. A brake disk 43 is arranged between each friction plate 42, and in order to match the thickness of the brake disk 43, the inner peripheral part of the friction plate 42 is offset in the center line direction with respect to the outer peripheral part. Annular facings made of friction material are fixed to both sides of the brake disc 43, and the inner peripheral end is spline-fitted to a spline formed on the outer peripheral surface of the output shaft 17, so that the facing can slide only in the direction of the center line. It is in a state of freedom.

Friction plate 42 located at the front end
A snap spring 44 disposed in front of the brake case 40 engages with the inner circumferential surface of the brake case 40, thereby restricting its forward movement. Further, the friction plate 42 disposed at the rear end is restricted from moving forward by a snap spring 45 disposed in front of it engaging with the inner circumferential surface of the brake case 40. Two cone springs 46 are arranged symmetrically behind the friction plate 42 so that their inner peripheries abut each other, and the outer periphery of the cone springs 46 is connected to a step formed on the inner periphery of the brake case 40. It is in a contracted state between the front end and the friction plate 42 at the rear end.
Curve A in FIG. 3 shows an example of the relationship between the compression stroke S of the cone spring 46 and the load P, and is a smooth curve having a maximum value a1 and a minimum value a2 between the compression strokes of the spring. In the state shown in FIG. 1, the forward movement of the rear end friction plate 42 is restricted by the snap spring 45, so the cone spring 46 is already compressed to the set position s1 in FIG. , the cone spring 46 is given an initial load indicated by p1 in FIG.

Next, the operation will be explained. Figure 1 shows the clutch ON (connected), and the coil spring 13
The clutch disk 15 is held between the flywheel 11 and the pressure plates 14 and 16 by urging the pressure plate 14 toward the flywheel 11, and the clutch disk 15 is held between the flywheel 11 and the pressure plates 14 and 16. Torque is flywheel 1
1. It is transmitted to the gear in the transmission case 18 via the clutch disk 15 and the output shaft 17. The generated torsional torque vibrations are absorbed by a damper mechanism provided on the clutch disk 15. Furthermore, as the flywheel 11 rotates, the cylinder shaft 24 also rotates via the clutch cover 12, support bolt 21, and sleeve 23, but the release bearing 25
Since the bearing cover 26 is provided with
The rotation is not transmitted to. On the other hand, in the state shown in FIG. 1, the bearing cover 26 is located at the front, and a clearance is formed between the projection 35 and the friction plate 42. Therefore, the brake disc 43 is not in pressure contact with the friction plate 42.

Next, when a clutch pedal (not shown) is depressed, the support shaft 29 rotates in the R direction. This rotation causes the yoke 28 to push the protrusion 27 rearward, and the bearing cover 26 moves rearward. As a result, the inner peripheral part of the release lever 22 rotates rearward around the pin of the support bolt 21 via the release bearing 25, the cylinder shaft 24, and the sleeve 23, and the coil spring 1
The pressure plate 14 is forcibly moved rearward against the spring force of 3. As a result, the clutch disk 15 is released from the flywheel 11 and the pressure plates 14, 16, and the clutch is placed in the OFF state (disconnected state). However, the outer periphery of the clutch disk 15 is
1. Slight contact with the pressure plates 14 and 16 will not completely release the torque transmission. Particularly in a multi-plate clutch like the one shown in FIG. 1, such co-rotation is likely to occur.

On the other hand, as the bearing cover 26 moves rearward, the pressure plate 31 integrally moves rearward. The protrusion 35 abuts against the front end friction plate 42, and further abuts against the pressure plate 31.
moves backward, each friction plate 4
The brake disc 43 is held between the two, and then the cone spring 46 begins to be compressed. The stroke end is set, for example, to s2 in Fig. 3, and the brake disc 43
The load received by (Fig. 1) travels on the curve A from p1 to the maximum value a1 during the stroke of the spring, and then p
Changes to 2. As can be seen from the shape of curve A,
The change in load P in this case is smaller than, for example, when a coil spring is used. That is, a substantially constant load suitable for braking the output shaft 17 can be obtained regardless of the degree to which the clutch pedal is depressed. Moreover, at the stroke end s2, the load that once increased to the local maximum value a1 decreases to p2. That is, by passing through the maximum value a1, a reliable braking force is once applied to the output shaft 17. Therefore, even if the present invention is applied to a multi-plate clutch that is likely to cause rotation, the output shaft 17 can be reliably braked, and abnormal noises in the transmission can be prevented. Furthermore, when the clutch is held in the OFF state for a certain period of time, for example when the vehicle is driven by coasting on a downhill slope with a small inclination, the load at the stroke end s2 is lower than the maximum value a1. No large friction force is generated on the brake disc 43. As a result, the inertia brake portion does not become hot, and the inertia brake does not seize or accelerate wear. In addition, since the brake disc 43 is directly clamped by the friction plate 42, the pressure plate 3
1, the rotation of the output shaft 17 is not transmitted from the brake disc 43. Therefore, strong twisting between the yoke 28 and the bearing cover 26 will not occur, and uneven wear will be prevented.

When the clutch pedal is released from the clutch OFF state, the coil spring 13 causes the flywheel 11 and the pressure plate 1 to move again.
The clutch disk 15 is clamped between the clutches 4 and 4, and the clutch shifts to the ON state. Pressure plate 14
Since the bearing cover 26 moves forward as the bearing cover 26 moves toward the flywheel 11 side, the pressure plate 31 also moves forward integrally.
Return to the position shown in Figure 1. As a result, the brake disk 43 is released from the friction plate 42, and the cone spring 46 extends from s2 to s1 in FIG.

Next, due to long-term use, the clutch disk 1
As the friction facing provided on the outer circumference of the pressure plate 5 wears out, the stopping position of the pressure plate 14 changes when the clutch is in the ON state. It becomes necessary to adjust the change in clearance between the two. In this case, when the vehicle is stopped, the lock bolt 34 is unscrewed and the lock bolt 34 is disengaged from the groove 33 of the pressure plate 31. Next, rotate the pressure plate 31 around the center line, and while unscrewing the cylindrical portion 32 from the bearing cover 26, remove the protrusion 35.
move backwards. When the clearance between the protrusion 35 and the friction plate 42 reaches an appropriate value, the lock bolt 34 is screwed in again to engage the split groove 33 and the pressure plate 31 is fixed to the bearing cover 26. Thereby, the clearance between the protrusion 35 and the friction plate 42 can be easily adjusted.

(Effect of the invention) Release bearing 25 of pull type clutch
A concentric pressure plate 31 is provided on the outer ring of;
Pressure plate 31 and clutch housing 2
A brake disc 43 slidably connected to the central output shaft 17 in the center line direction is arranged between the inner peripheral parts of the clutch housing 20; a friction plate 42 is disposed on at least the inner peripheral part side of the clutch housing 20 on both sides of the brake disc 43. provided; friction plate 4
2 is provided with a spring mechanism that elastically biases the output shaft 17 from the clutch housing 20 side; In a pull type clutch with an inertia brake that brakes the output shaft 17 when the clutch is disengaged; The mechanism is composed of two cone springs 46 arranged symmetrically so that their inner peripheries abut each other; Since it is set so that the maximum value a1 is shown in the middle part; (a) Compared to the conventional configuration that uses a coil spring, the inertia braking force is generally constant regardless of changes in the degree of clutch depression; Therefore, an appropriate braking force of the output shaft 17 can be easily obtained. Therefore, the conventional problem of requiring skill to operate the clutch pedal can be solved. Furthermore, problems such as the vehicle stopping due to excessively strong braking force do not occur.

(b) Even if the clutch is held in a disengaged state for a certain period of time, strong inertia braking force is not generated, so the friction plate is unlikely to become hot, and the inertia brake will not seize or accelerate wear. This allows for long-term stable operation.

(c) Since the spring mechanism is composed of two cone springs arranged symmetrically with their inner peripheries abutting each other, the release stroke becomes longer, making half-clutch operation easier. Therefore, the operability is improved from this point as well. Moreover, since it uses two cone springs that are arranged symmetrically with their inner peripheries abutting each other, even if this invention is adopted for industrial construction equipment where clutch connection/disconnection operations are frequently performed, the cone springs will There is no fear that it will bend back into the opposite position.

(d) Moreover, the combined load of both cone springs 46 is the set position s1 of both cone springs 46.
Since the maximum value a1 is set approximately in the middle between the stroke end s2 and the stroke end s2, the load that once increased to the maximum value a1 decreases to p2 at the stroke end s2. Therefore, a reliable braking force is once applied to the output shaft 17 by passing through the maximum value a1.
Therefore, even if the present invention is applied to a multi-plate clutch that is likely to cause rotation, the output shaft 17 can be reliably braked, and abnormal noises in the transmission can be prevented. Mata clutch OFF
When the state is held for a certain period of time, for example when the vehicle is coasting on a downhill slope with a small slope, the stroke end s2
Since the load at 43 is lower than the local maximum value a1, a large frictional force
It never occurs. As a result, the inertia brake portion does not become hot, and the inertia brake does not seize or accelerate wear.

(Another embodiment) (a) The compression characteristics of the cone spring 46 are not limited to the case shown in curve A in FIG. The curve C may have a characteristic in which the difference between the two is not large, and the stroke end s2 and the minimum value coincide with each other.
It may also have a characteristic like .

(b) The number of brake discs 43 is not limited to two, and may be one or three or more. Of course, it is necessary to change the number of friction plates 42 in accordance with the number of brake discs 43.

(c) The friction plate 42 on the pressure plate 31 side can also be omitted. However, if a friction plate 42 is provided on the pressure plate 31 side, the yoke 2 that drives the release bearing 25 when the inertia brake is activated
Unbalanced loads are no longer applied to members such as No. 8, and problems such as uneven wear do not occur.

(d) The present invention can be similarly applied to clutches having one clutch disc 15 or three or more clutch discs 15. However, it is particularly suitable for cases where there are two or more clutches that are likely to have poor disengagement.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view of a pull-type clutch according to the present invention, FIG. 2 is a partial cross-sectional view of FIG. 1, and FIG. 3 is a graph showing the relationship between compression stroke and load. 17... Output shaft, 20... Clutch housing, 25... Release bearing, 31...
...pressure plate, 42...friction plate, 43...brake disc, 46...cone spring (spring mechanism), a1...local maximum value,
P...load, S...compression stroke, s1...set position, s2...stroke end.

Claims (1)

[Scope of utility model registration request] A concentric pressure plate is provided on the outer ring of the release bearing of the pull-type clutch; a brake disc connected to the central output shaft so as to be slidable in the center line direction is arranged between the pressure plate and the inner circumference of the clutch housing. A friction plate is provided on at least the inner circumferential side of the clutch housing on both sides of the brake disc; a spring mechanism is provided that elastically biases the friction plate from the clutch housing side; the output shaft is braked when the clutch is disengaged; In such a pull type clutch with an inertia brake, in order to increase the release stroke, the spring mechanism is composed of two cone springs arranged symmetrically with their inner peripheries in contact with each other; both cone springs A pull-type clutch with an inertia brake, characterized in that the combined load of the two cone springs is set to reach a maximum value approximately midway between the set position of both cone springs and the stroke end.