JP2002106596A - Friction facing and friction disc - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce malfunctions such as a breakage of a friction facing used for a friction disc of a clutch disk, etc. SOLUTION: The friction facing and the friction disc are characterized in that the friction facing 11, 12 is pressed to a flywheel to make it possible to frictionally engage therewith and is provided with an annular plate having a main face making a friction block 11h. Holes 11a, 12a fixing a plurality of rivets are formed in the annular plate and recesses 11f, 12f surrounding the holes 11a, 12a are formed in the main face.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a friction facing and a friction disk using the same.

[0002]

2. Description of the Related Art A clutch disk used in a vehicle clutch device is a disk-shaped and annular member disposed between a friction surface of a flywheel and a pressure plate. The clutch disk is mainly composed of two friction facings and a core plate disposed therebetween. The core plate includes, for example, a mounting portion on the outer peripheral side,
And a fixing portion fixed to the damper portion on the inner peripheral side. Friction facing is fixed to the mounting portion via, for example, rivets. A plurality of rivet fixing holes are formed in each friction facing. These holes are formed side by side on the same circle. In addition, a plurality of grooves are formed on a main surface of the friction facing (a plane that forms a friction surface facing the flywheel or the pressure plate).

A plurality of grooves are formed on the main surface of the friction facing shown in Japanese Utility Model Publication No. 56-12. The concave groove is a shallow groove slightly recessed from the friction surface. The type of groove is
It comprises a plurality of radial grooves extending in the radial direction and a circumferential groove extending in the circumferential direction.

[0004]

The circumferential groove formed in the main surface of the friction facing shown in Japanese Utility Model Publication No. 56-12 is formed so as to cover a rivet fixing hole of the friction facing.

[0005] For this reason, the portion of the circumferential groove that is in contact with the fixing hole has a low strength and is easily peeled off by a clutch operation or the like. The peeled portion is caught between the flywheel and the clutch disk, for example, and causes problems such as hindering the operation when the clutch disk separates from the flywheel (clutch disengagement failure).

It is an object of the present invention to reduce problems such as breakage of friction facings used for friction disks such as clutch disks.

[0007]

According to a first aspect of the present invention, there is provided a friction facing which is capable of being frictionally engaged by being pressed against another rotating member and having an annular plate having a main surface constituting a friction surface. I have. A plurality of fixing holes are formed in the annular plate, and a recess surrounding the fixing hole is formed in the main surface.

In this friction facing, since the fixing hole is surrounded by the concave portion, the edge portion such as the concave groove does not touch. Therefore, damage to the friction facing at the fixing hole portion is less likely to occur.

In the friction facing according to the second aspect,
In claim 1, a circumferential groove is formed on the main surface,
The recess forms a part of the circumferential groove. Here, the circumferential groove is a groove extending at least in the circumferential direction of the friction facing, and includes an annular groove (a perfect circle, an ellipse, etc.) and a plurality of arc-shaped grooves.

In this friction facing, the recess of the circumferential groove surrounds the fixing hole. In other words, the fixing hole is formed in a recess in the circumferential groove. As described above, since the edge portion such as the concave groove does not cover the fixing hole, breakage of the friction facing in the fixing hole portion hardly occurs.

According to a third aspect of the present invention, there is provided a clutch disc according to the first or second aspect, a core plate disposed between the two friction facings, and a friction facing disposed in a fixing hole of the friction facing. And a fixing member for fixing the core plate.

[0012]

1 and 2 show a clutch device 1 including a clutch disk assembly 2 according to one embodiment of the present invention. The clutch device 1 is a device for transmitting and interrupting torque from a flywheel 90 on the engine side to an input shaft (not shown) of a transmission. The axis OO in FIG. 1 is the rotation axis of the clutch device 1. This rotation axis OO is a flywheel 90
Are orthogonal to the friction engagement surface 90a. Further, an arrow R1 in FIG. 2 is the positive side (drive side) in the rotational direction of the clutch device 1, and an arrow R2 is the negative side in the rotational direction.

The flywheel 90 has a flat and annular friction engagement surface 90a facing the transmission side in the axial direction. Further, a hole 90b is formed in the flywheel 90 so as to penetrate in the axial direction in order to discharge abrasion powder.

<Structure of clutch device> Clutch device 1
Is mainly composed of a clutch disk assembly 2 and a clutch cover assembly 3 fixed to the flywheel 90.

The clutch disk assembly 2 comprises an inner peripheral damper portion 2a and an outer peripheral clutch disk 2b. The input shaft of the transmission is spline-engaged with the inner peripheral portion of the damper portion 2a. The clutch disk assembly 2 will be described later in detail.

The clutch cover assembly 3 is an assembly for pressing the clutch disc 2b against the flywheel 90 to frictionally connect or disconnect the connection. The clutch cover assembly 3 mainly includes the clutch cover 31
, A pressure plate 32, and a pressure plate moving mechanism 33.

The clutch cover 31 is an annular member, and the outer peripheral portion is fixed to the flywheel 90. As shown in FIG. 1, the pressure plate 32 is arranged such that the friction engagement surface on the flywheel 90 side faces the friction engagement surface 90a of the flywheel 90 with the clutch disc 2b interposed therebetween. This pressure plate 32
Are supported by the clutch cover 31 so as to be relatively non-rotatable and movable in the axial direction.

The pressure plate moving mechanism 33 mainly includes a plurality of coil springs 33a and a release lever 33b. Coil spring 3
3a extends in the direction of the rotation axis OO, one end of which abuts the clutch cover 31, and the other end thereof
It is in contact with 2. The coil spring 33a applies a pressing force to the pressure plate 32 on the flywheel 90 side. The release lever 33b is a member that raises the pressure plate 32 to the side opposite to the flywheel 90 in conjunction with the movement of a clutch operating mechanism (not shown). When a release device (not shown) of the clutch operating mechanism applies a force on the flywheel 90 side to the inner end of the release lever 33b, the pressure plate 32 connected to the outer end of the release lever 33b becomes
It moves to the side opposite to flywheel 90.

<Detailed Configuration of Clutch Disk Assembly> The details of the clutch disk assembly 2 will be described below. (Damper part) The damper part 2a on the inner peripheral side of the clutch disk assembly 2 is a structure that plays a role of absorbing and attenuating the torque fluctuation.
Clutch plate 22 and retaining plate 23
And a torsion spring 24.

The spline hub 21 has a spline hole 21a at the center thereof which meshes with spline teeth of the input shaft of the transmission. The spline hub 21 is integrally formed with a flange 21b extending outward from a cylindrical main body. A window hole is formed in the flange 21b, and the torsion spring 24 is accommodated in the window hole.

A clutch plate 22 and a retaining plate 23 are arranged so as to sandwich the flange 21b of the spline hub 21. These plates 22,
23 are a pair and are non-rotatably connected by pins. These plates 22 and 23 also have window holes 22a and 23 corresponding to the window holes of flange 21b.
a is formed. These window holes 22a, 23a
The torsion spring 24 is cut and raised so as to cover it from the outside, and the torsion spring 24 is housed therein.

The two ends of the torsion spring 24 are in contact with both plates 22, 23 and both ends of the window hole of the flange 21b, and the two plates 22, 23 and the spline hub 21 are connected.
The torque is transmitted between and.

A friction washer 2 is provided between the inner periphery of the clutch plate 22 and the inner periphery of the flange 21b.
5 are arranged. A friction washer 26, a friction plate 27, and a cone spring 28 are arranged between the inner periphery of the flange 21b and the inner periphery of the retaining plate 23. By sliding these friction washers 25 and 26 between the flange 21b and the plates 22 and 23, a predetermined frictional force (hysteresis torque) for attenuating torque fluctuation (torsional vibration) during compression of the torsion spring 24.
Occurs.

The outer peripheral portion 22 of the clutch plate 22
b is a portion to which the inner peripheral portion 10a of the core plate 10 of the clutch disc 2b is fixed, and a plurality of holes are formed at equal intervals in the circumferential direction.

(Clutch Disk) The clutch disk 2b disposed on the outer peripheral side of the clutch disk assembly 2
It mainly comprises a core plate 10 and two types of friction facings 11 and 12. Friction facing 1
1 is disposed on the pressure plate 32 side, and the friction facing 12 is disposed on the flywheel 90 side.

A plurality of core plates 10 are arranged at equal intervals in the circumferential direction. Each core plate 10 has an inner peripheral portion 10a and a mounting portion 10 located outside the inner peripheral portion 10a.
b. The inner peripheral portion 10a is a portion that overlaps with the outer peripheral portion 22b of the clutch plate 22,
It is fixed to the outer peripheral portion 22b with rivets 40. The mounting portion 10b is a portion where the friction facings 11 and 12 are mounted on both surfaces thereof.

As shown in FIG. 2, a plurality of mounting holes 10c are formed in the mounting portion 10b. Specifically, a total of four mounting holes 10c are formed in each mounting portion 10b. The mounting holes 10c are arranged so as to form substantially square vertices. Two mounting holes 1 on one side in the rotation direction (in this embodiment, on the side of rotation R1) in each mounting portion 10b.
0c is a rivet 41 fixed to the friction facing 11
Are mounted, and the two mounting holes 10c on the opposite side in the rotation direction (the rotation direction R2 side in the present embodiment) are
Is attached. Each mounting part 10
The two mounting holes 10c on the inner peripheral side of b are arranged on the circle A, that is, at the same radial position. Each mounting part 10
The two mounting holes 10c on the outer peripheral side of b are arranged on the circle B, that is, at the same radial position. Circle A and Circle B
Is a perfect circle centered on the center O, and the circle B has a larger diameter than the circle A.

The friction facings 11 and 12 are annular disk-shaped members. The friction facings 11 and 12 are attached to the mounting portion 10 of the core plate 10 by a plurality of rivets 41.
b is mounted on both sides. Friction facings 11 and 12 are attached to both sides of one core plate 10, respectively. Friction facing 11,12
The mounting portion 10b on which is mounted the friction facing 11,
12 together with the frictional engagement portion, and becomes a target to be sandwiched between the flywheel 90 and the pressure plate 32. (Friction facing) Holes 11a and 12a are formed in the friction facings 11 and 12 at positions corresponding to the mounting holes 10c of the core plate 10. In each mounting portion 10b, the rivet 41 arranged in the mounting hole 10c on the rotation direction R1 side is fixed to the hole 11a of the friction facing 11. In each mounting part 10b, the rotation direction R1
The rivet 41 arranged in the mounting hole 10 c on the side is fixed to the hole 12 a of the friction facing 12. As shown in FIG. 4, the head of each rivet 41 on the side of the core plate 10 is arranged in a friction facing hole on the side not fixed by the rivet.

The main surfaces of the friction facings 11 and 12 (planes opposite to the core plate 10, the plane facing the pressure plate 32 in the friction facing 11, and the frictional engagement surface of the flywheel 90 in the friction facing 12 90a) functions as a friction surface.

The main surfaces of the friction facings 11 and 12 include:
A plurality of radial grooves 11b and 12b extending in the radial direction are formed. The radial grooves 11b and 12b are shallow grooves slightly lower than the friction surface portion of the main surface, and communicate from the radial inner edge to the radial outer edge of the annular main surface. A total of 36 radial concave grooves 11b and 12b are formed. As a result, the friction surface on the main surface is reduced, and the negative pressure suction effect can be reduced.

Further, the main surfaces of the friction facings 11 and 12 are provided with a plurality of circumferential grooves (11) extending in the rotational direction.
c, 12c to 11e, 12e) are formed. The circumferential grooves (11c, 12c to 11e, 12e) are, like the radial grooves 11b, 12b, shallow grooves slightly lower than the friction surface portion of the main surface. Circumferential groove (1
1c, 12c to 11e, 12e) are, in order from the inner peripheral side, first circumferential grooves 11c, 12c, second circumferential grooves 11d, 12d, and third circumferential grooves 11e, 12e. Has become. The first circumferential grooves 11c and 12c are formed at substantially the same radial position as the above-described first circle A, and the second circumferential grooves 11d and 12d are formed in the radial direction between the first circle A and the second circle B. The third circumferential concave grooves 11e, 12e are formed at intermediate positions.
e is formed at the same radial position as the second circle B.

The first circumferential grooves 11c and 12c and the third circumferential grooves 11e and 12e are annularly continuous in the circumferential direction, while the second circumferential grooves 11d and 12d are annular. It is composed of a plurality of arc-shaped concave grooves. In other words, the plurality of second circumferential grooves 11d, 12d are
h block each other in the direction of rotation.

Further, the first to third circumferential grooves 11c, 11c,
12c to 11e and 12e are formed in an elliptical shape.
Specifically, the first to third circumferential grooves 11c, 12c,
In the ellipses corresponding to 11e and 12e, the major axis is located in the vertical direction in FIG. 3, and the minor axis is located in the horizontal direction in FIG. As a result, the major axis of the ellipse coinciding with the first circumferential grooves 11c, 12c is larger than the diameter of the first circle A, and the minor axis is the first circle A.
Smaller than the diameter of Further, the third circumferential groove 11e, 1
The major axis of the ellipse corresponding to 2e is larger than the diameter of the first circle A, and the minor axis is smaller than the diameter of the first circle A.

In the main surfaces of the friction facings 11 and 12, portions corresponding to the holes 11a and 12a are provided with concave portions 11f and 11f.
12f is formed. As shown in FIG.
f, 12f are circumferential grooves (11c, 12c to 11c).
e, 12e) and the radial grooves 11b, 12b are shallow grooves slightly lower than the friction surface portion of the main surface. However, the concave portions 11f and 12f are formed in the circumferential concave grooves (1
1c, 12c to 11e, 12e) and radial grooves 11b,
While 12b is elongated in plan view,
It has a block shape having a constant circumferential width and radial width. The recesses 11f and 12f completely surround the holes 11a and 12a, and the edge of the recess 11f is
It does not affect a. Therefore, the strength of the edge portion of the concave portion 11f does not decrease, and breakage and the like hardly occur. That is, the disconnection failure of the clutch due to the peeled portion is unlikely to occur.

In each of the mounting portions 10b, 2
The two concave portions 11f corresponding to the one mounting holes 10c are formed continuously in the circumferential direction. The recesses 11f corresponding to the two mounting holes 10c on the inner peripheral side of each mounting portion 10b are
It is continuous with the circumferential grooves 11c and 12c. In other words, the concave portion 11f on the inner peripheral side is the first circumferential concave groove 11c,
It can be said that it constitutes a part of 12c. That is, the first circumferential grooves 11c and 12c are formed in the rivet holes 11a and 12a.
The width in the radial direction is increased in the portion, and the edge is
a, 12a. Also, two mounting holes 1 on the outer peripheral side of each mounting portion 10b.
0c is the third circumferential groove 11f.
e and 12e. In other words, it can be said that the concave portion 11f on the outer peripheral side forms a part of the third circumferential concave grooves 11e and 12e. That is, the third circumferential groove 11
The e and 12e may be regarded as having a larger width in the radial direction at the rivet holes 11a and 12a so that the edges do not cover the holes 11a and 12a.

The plurality of radial grooves 11b described above,
12b, circumferential grooves 11c, 12c to 11e, 12e
And the recess 11f, the friction facings 11, 12
Is divided into a plurality of small friction surface blocks 11h.

An opening 42 is provided between the clutch disk 2b and the damper portion 2a to allow the space SA on the flywheel 90 side to communicate with the space SB on the clutch cover assembly 3 side. Specifically, the opening 42 is provided between the rotation directions on the inner peripheral side of each core plate 10 and the clutch plate 2.
2 and a gap between the friction facings 11 and 12 in the radial direction.

The friction facings 11 and 12 are formed with positioning notches 11g and 12g. Notch 11
g and 12g are notch-shaped portions slightly concave on the inner peripheral side at the outer peripheral edges of the friction facings 11 and 12, and are formed at a plurality (three places) at equal intervals in the circumferential direction. By reading the notches 11g and 12g with a sensor, the holes 11a and 12a can be reliably formed in the recess 11f. To summarize the above, friction facing 1
1 and 12 have a mark portion for detecting a position or a posture for forming the holes 11a and 12a at predetermined positions.

<Operation of Clutch Device> Next, the operation of the clutch device 1 will be described. First, the operation of releasing the clutch connection from the clutch connection state will be described.

When the release device (not shown) of the clutch operating mechanism pushes the release lever 33b toward the flywheel 90 in accordance with the clutch operation, the pressure plate 3
2 moves to the opposite side of the flywheel 90. Then
The clutch connection state is released, and the clutch disk 2b of the clutch disk assembly 2 shifts to a state where it is separated from the flywheel 90 and the pressure plate 32. As a result, the clutch disc 2
b and the torque transmitted to the input shaft of the transmission via the damper portion 2a is interrupted at a portion transmitted from the flywheel 90 to the clutch disk 2b.

Next, the operation of connecting the clutch from the state in which the clutch is released will be described. When the release device (not shown) of the clutch operation mechanism returns the release lever 33b to the side opposite to the flywheel 90 according to the clutch operation, the pressure plate 32 is pressed toward the flywheel 90. Accordingly, the clutch disc 2b is gradually held between the flywheel 90 and the pressure plate 32, and the torque from the flywheel 90 is transmitted to the input shaft of the transmission via the clutch disc 2b and the damper portion 2a. Be transmitted.

<Improvement of Negative Pressure Adsorption Phenomenon> Generally, the air pressure in the space SA on the flywheel 90 side of the clutch disc assembly 2 is reduced by the hole 90b of the flywheel 90 and the opening 42 of the clutch disc assembly 2 due to the clutch cover. The pressure may be lower than the pressure of the space SB on the assembly 3 side. In this case, a phenomenon occurs in which the clutch disk assembly 1 is attracted to the flywheel 90 due to a pressure difference, and a clutch drag torque may be generated.

However, in the structure of the above embodiment, due to the following characteristics, the phenomenon that the clutch disk assembly 2 is attracted to the flywheel 90 due to the pressure difference is suppressed, and the occurrence of clutch disconnection is less likely to occur.

A) Since the circumferential groove is elliptical,
During expansion due to frictional heat, the inner and outer peripheral portions of the friction facings 11 and 12 are bent at the boundary of the circumferential groove, and the planar contact with the flywheel 90 and the like is actively broken.
As a result, the disengagement of the clutch is improved.

B) Since a large number of radial concave grooves 11b are formed, the friction surface block 11h is divided into a large number in the circumferential direction to reduce negative pressure attraction. c) In the above embodiment, the combination of three or more circumferential grooves and a large number of radial grooves greatly reduces the clutch drag torque. The contents will be described in detail in the following embodiments.

[0046]

EXAMPLE A clutch drag torque was measured by the friction facing according to the present invention and the conventional friction facing.

In the experimental data shown in FIG.
In a structure having only about eight radial grooves (first prior art), the rotation speed changes up and down, and a structure in which about 16 to 18 radial grooves are provided with two circumferential grooves (second example). Conventional technology)
In this case, the change in the number of revolutions is small and the rotation speed is stable at 200 to 300 rpm. On the other hand, three circumferential grooves
A structure in which six radial grooves are provided (an experimental example according to the present invention)
Then, the rotation speed changes to almost 0. That is, the clutch drag torque becomes substantially zero.

As described above, the clutch drag torque can be reduced by a combination of 20 or more radial grooves, preferably 30 or more and 40 or less, and 3 or more and more preferably 4 or 5 or less circumferential grooves. It can be seen that the function of reducing has been dramatically improved. [Other Embodiments] In the above embodiment, the core plate has a flat plate shape, but may have a cushioning function capable of bending in the axial direction. Further, the core plate may be formed of a single member integrally formed in the circumferential direction.

The number, shape, and position of the grooves formed in the friction facing are not limited to the above-described embodiment.

[0050]

In the friction facing and the friction disk according to the present invention, since the fixing hole is surrounded by the concave portion, the edge portion such as the groove does not touch. Therefore, damage to the friction facing at the fixing hole portion is less likely to occur.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a clutch device including a clutch disk assembly according to one embodiment of the present invention.

FIG. 2 is a plan view of a clutch disk assembly.

FIG. 3 is a plan view of friction facing.

FIG. 4 is a longitudinal sectional view of friction facing.

FIG. 5 is a diagram showing comparative experimental data of clutch drag torque.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Clutch device 2 Clutch disk assembly 2b Clutch disk 3 Clutch cover assembly 10 Core plate 11,12 Friction facing 11a, 12a Hole (fixing hole) 11b, 12b Radial groove 11c, 12c ~ 11e, 12e Circumferential concave Groove 11f, 12f Recess 41 Rivets (fixing member)

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Hideyuki Imanaka 1-1-1 Kida Motomiya, Neyagawa-shi, Osaka F-term in EXEDY Corporation (reference) 3J056 AA58 AA62 BA01 BB12 BC01 BE01 CA04 CA09 CA15 CA18 EA02 EA05 EA16 GA02 GA12

Claims (3)

[Claims] 1. A friction facing capable of being frictionally engaged by being pressed against another rotating member, comprising: an annular plate having a main surface constituting a friction surface, wherein a plurality of fixing holes are formed in the annular plate. A friction facing, wherein a concave portion surrounding the fixing hole is formed in the main surface. 2. The friction facing according to claim 1, wherein a circumferential groove is formed in the main surface, and the recess forms a part of the circumferential groove. 3. The two friction facings according to claim 1 or 2, a core plate disposed between the two friction facings, and the two friction facings disposed in the fixing holes of the friction facings. A friction disc comprising: a friction facing of claim 1; and a fixing member for fixing the core plate.