JP3202879B2 - Friction plate - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a friction plate having a friction damping force applied to, for example, a clutch disk of an automobile.

[0002]

2. Description of the Related Art As a conventional friction plate of this type, for example, as shown in FIG. 14, there is a friction plate applied to a clutch disk 100 used for an automobile or the like.

[0003] Generally, this clutch disc 100
In order to absorb torsional shock and vibration during power transmission,
Clutch plate 101, retaining plate 10
2. An input side member including a cushioning plate 103, a friction facing 104, etc., capable of inputting a rotational force from the engine side, and a spline serving as an output side member for outputting a rotational force to an output shaft (not shown). Hub 1
05 is resiliently and relatively rotatably assembled by a torsion spring 106.

A ring-shaped friction member, which is a friction plate which is always slidably pressed against the clutch plate 101 and the retaining plate 102, is provided between the flange 105A which is formed integrally with the spline hub 105 and which protrudes to the outer peripheral side, and the clutch plate 101 and the retaining plate 102. A friction washer 107 as a plate body is interposed. That is, the friction washer 107 is formed by the flange 105A of the spline hub 105, the clutch plate 101, and the retaining plate 10.
2 when the clutch disc 100 is interrupted by the friction damping force generated when the clutch disc 100 slides.
The torsional vibration (shock) caused by the expansion / contraction operation of the damper 06 is attenuated (torque fluctuation in the torsional direction is absorbed).

[0005]

However, the friction washer 107 of the prior art described above slides with a high load on the flange 105A of the spline hub 105, which is a metal part of the mating member, to absorb torque fluctuations in the torsional direction. Therefore, the state (surface roughness and the like) of the sliding surface 108 changes,
Generally, as the wear progresses, the friction coefficient of the material itself increases, and since the shape is rectangular in cross section as shown in FIG. 13, the radial width of the sliding surface 108 does not change with the progress of wear. Since the sliding radius r does not change,
The coefficient of friction associated with the shape hardly changes. Therefore, as the wear progresses, the friction coefficient of the material of the friction washer 107 itself only increases, and the sliding torque increases. As a result, the power transmission performance when the clutch disc 100 is connected is impaired.

[0006] The present invention has been made to solve the above-mentioned problems of the prior art.
An object of the present invention is to provide a friction plate capable of suppressing an increase in sliding torque regardless of progress of wear.

[0007]

In order to achieve the above object, according to the present invention, in a friction plate having a ring-shaped friction plate main body, a sliding radius on a sliding surface of the friction plate main body is as follows. It is characterized in that the shape gradually becomes inner as the wear progresses in the axial direction.

Preferably, at least the inner peripheral shape of the inner and outer peripheral shapes of the friction plate main body is such that the sliding radius on the sliding surface is gradually inward as the wear progresses in the axial direction.

[0009]

In the friction plate having the above-described structure, the ring-shaped friction plate body is formed such that the sliding radius on the sliding surface becomes gradually inward as the wear progresses in the axial direction. In this stage, the sliding radius becomes outside and the generated sliding torque increases. Thereafter, as the friction plate body wears in the axial direction due to use, the sliding radius gradually becomes inward, so that it acts in a direction to suppress the generated sliding torque. On the other hand, since the friction coefficient of the material itself increases due to the surface roughness of the sliding surface due to wear, the sliding torque acts in a direction to increase. As described above, the increase in the sliding torque is suppressed by the opposing action of the shift of the sliding radius toward the inside and the increase in the friction coefficient of the material itself, and the increase ratio with the initial sliding torque can be reduced. That is, it is possible to suppress the increase in the sliding torque regardless of the progress of the wear.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the illustrated embodiments. 1 to 4 show a friction plate according to an embodiment of the present invention. This friction plate is applied to a clutch disk 2 used in a torque transmission 1 as a power transmission device for an automobile or the like as shown in FIG.

In the drawing, reference numeral 3 designates a spline hub as an output side member which is spline-fitted to the output shaft 4 for the transmission 1 shown in FIG. 4, and the spline hub 3 is integrally formed with a flange 5 projecting to the outer peripheral side. Is formed. A plurality of stop pin notches 5A are formed on the outer periphery of the flange 5 at predetermined intervals, and a plurality of window holes 5B are formed on the inner periphery thereof at equal intervals in the circumferential direction. The torsion spring 6 is accommodated in each window hole 5B.

7A. Reference numeral 7B denotes a pair of friction facings slidably pressed against the flywheel 8 and the pressure plate 9 shown in FIG. 4, and a pressure plate 9 is provided between the friction facings 7A and 7B.
A plurality of cushioning plates 10 are interposed for buffering an impact when the is pressed against the friction facing 7A.

The cushioning plate 10 is formed into a corrugated shape by, for example, a steel plate as a metal part, and the front and back portions of the cushioning plate 10 are joined by friction rivets 11 to friction facings 7A and 7B.

Further, the cushioning plate 10 includes
An engaging portion 10A protruding inward is integrally formed, and the engaging portion 10A is connected to an outer peripheral edge of the clutch plate 13 by a cushioning rivet 12.

Reference numeral 14 denotes a retaining plate disposed opposite to the clutch plate 13. The retaining plate 14 is integrally connected to the clutch plate 13 via a stop pin 15. The stop pin 15 is arranged in the notch 5 </ b> A for the stop pin of the flange 5. With the stop pin 15, the clutch plate 13 and the retaining plate 14 are assembled so as to sandwich the flange 5 of the spline hub 3, and are relatively rotatable with respect to the spline hub 3.

In addition, window holes 13A, 14A are formed in the clutch plate 13 and the retaining plate 14, respectively, corresponding to the window holes 5B of the flange 5 of the spline hub 3. Eaves 13B, 14B are formed at the radially outer and inner edges of the window holes 13A, 14A so as to cover the torsion spring 6 from the outside.
A torsion spring 6 for absorbing a large impact in the torsional direction of the clutch disc 2 is accommodated in the eave portions 13B, 14B and the window hole 5B so as to be compressible in the circumferential direction.

Between the flange 5 of the spline hub 3 and the radially inner portion of the retaining plate 14, a friction as a ring-shaped friction plate main body is interposed via a ring-shaped cone spring 16 and a friction plate 17. A washer 18 is provided. Further, a friction washer 18 as a ring-shaped friction plate main body is disposed between the flange 5 and a radially inner portion of the clutch plate 13. These friction washers 18 are constantly slidably pressed against the flange 5, the clutch plate 13 and the retaining plate 14, and the flange 5, the clutch plate 13 and the retaining plate 1 are slidably pressed.
4 generates a sliding torque when relatively rotating.

As shown in FIG. 1, the friction washer 18 has a substantially trapezoidal cross section and an inverted conical shape on the sliding surface side of the spline hub 3 with respect to the flange 5. More specifically, the outer peripheral portion is a flat portion 18A having a predetermined width and a tapered portion 18B whose inner peripheral shape is reduced in diameter inward in the radial direction.

Next, the operation will be described with reference to the pull type transmission 2 shown in FIG.

When the diaphragm spring 20 is pushed toward the engine by the withdrawal lever 19, the friction facing 7B is joined to the flywheel 8 by the pressure plate 9, and the clutch disc 2 is connected (see FIG. 4A). . In this connection, the clutch plate 13 is connected via the friction facings 7A and 7B.
And the torque is transmitted to the retaining plate 14.
Then, the transmitted torque is transmitted to the flange 5 via the torsion spring 6, and the spline hub 3
To the output shaft 4.

At this time, the torsion spring 6 repeats the expansion and contraction operation. Further, in the twisting operation until the clutch plate 13 and the retaining plate 14 rotate integrally with the flange 5, relative rotation occurs between the clutch plate 13 and the retaining plate 14, and the friction washers 18, 18 and the cone spring 1 are rotated.
The hysteresis torque according to 6 is obtained.

On the other hand, when the withdrawal lever 19 is pulled toward the transmission, the pressure plate 9 separates from the friction facing 7A and the clutch disc 2
Is in a disconnected state (see FIG. 4B).

When the connection and disconnection of the clutch disk 2 are performed in this manner, the flat portion 18A of the friction washer 18 serving as the sliding surface 18C with the flange 5 is worn in the axial direction. Normally, as the friction washer 18 wears in the axial direction, the sliding torque increases, and the power transmission performance when the clutch disc 2 is connected is impaired.

However, the shape of the friction washer 18 according to one embodiment of the present invention is such that the outer peripheral portion is flat.
A, and the inner peripheral shape thereof is an inverted conical tapered portion 18B.
Accordingly, as the wear progresses in the axial direction, the inner peripheral surface of the flat portion 18A gradually moves radially inward. Therefore, the sliding surface 18C increases toward the inside in the radial direction, and the sliding radius becomes inside.

That is, at the initial stage, the sliding radius r is on the outer peripheral side, and the sliding radius r gradually shifts inward as the wear progresses in the axial direction (see the two-dot chain line portion in FIG. 1). Thus, in the initial stage, since the sliding radius r is outside, the generated sliding torque can be set large. Then, as the wear progresses in the axial direction, the sliding radius r gradually becomes inside, so that it acts in a direction to suppress the generated sliding torque. On the other hand, the sliding surface 18 due to the progress of wear
The coefficient of friction of the material itself increases due to the surface roughness of C and the like, which acts in the direction of increasing the sliding torque. The opposing effects of these two can suppress the increase in the sliding torque, and can reduce the increase ratio with respect to the initial sliding torque. As described above, the increase in the sliding torque of the friction washer 18 is suppressed, so that the power transmission at the time of connecting the clutch disk 2 is always reliably performed.

Next, a comparative example will be described in which the frictional washer 18 according to the present embodiment and the frictional washer 107 according to the conventional example are increased in sliding torque due to axial wear.

As shown in FIG. 5, the dimensions of the flexure washer 18 of the present embodiment, which is a sample for the test, have an outer diameter D.
1: φ69mm, inner diameter D2: φ53mm, flat part 18A
Inner diameter D3: φ67 mm, that is, the width W of the flat portion 18A: 1 mm, the thickness T: 3.25 mm, the angle α of the tapered portion 18B: 1 ° 40 ′, that is, the axial length L of the tapered portion 18B: 0.2 mm. is there. On the other hand, the dimensions of the conventional flexure washer 107 are, as shown in FIG.
Since it does not have B, the outer diameter D1: φ69 mm, the inner diameter D2: φ53 mm, and the thickness T: 3.25 mm.

A schematic configuration of the test apparatus 200 will be described with reference to FIG. The test apparatus 200 includes a turntable 20 on which the friction washers 18 and 107 are mounted as samples.
1 and a mating member 202 which is a fixed member on which the friction washers 18 and 107 slide.
The frictional washers 18 and 107 are mounted on the mating member 01 with the sliding surface facing the mating member 202, a load is applied to the mating member 202 and pressed, and the turntable 201 is rotated to measure the sliding torque. Table 1 below shows the test conditions.

[0029]

[Table 1] The results of the test performed as described above are shown in Table 2 below.

[0030]

[Table 2] As shown in Table 2, the friction washer 18 of the present embodiment is better than the conventional friction washer 107.
, The increase ratio of the sliding torque is smaller. That is, an improvement of about 30% was obtained as compared with the conventional shape.

In the above-described embodiment, the friction washer is formed as an inverted cone having a flat portion as an example. However, as shown in FIG. The shape may be a quadratic curved surface shape in accordance with the progression, as shown in FIG. 8, a straight line having a predetermined length in the axial direction, and then an inverted conical shape.
As shown in FIG. 1, a concave portion having a circular cross section may be used.
It is also possible to adopt a stepped shape as shown in FIG. These are only the inner peripheral shape changed. However, as shown in FIG. 11, the outer peripheral shape may be a conical tapered portion 18B ′ in which the angle of the inverted conical inner peripheral tapered portion 18B is larger than that of the inverted conical inner peripheral taper portion 18B. good. Further, as shown in FIG. 12, the inner peripheral shape on both sides in the axial direction may be an inverted conical tapered portion 18B. With such a shape, it is possible to cope with sliding in both directions, and it is not necessary to distinguish the sliding surface side for mounting, and mounting is facilitated.

Further, in the above-described embodiment, an example in which the present invention is applied to a clutch disk of an automobile or the like has been described. However, the present invention can be similarly applied to other general-purpose clutch disks.

[0033]

The present invention has the above-described structure and operation, and slides the shape of the ring-shaped friction plate body (at least the inner peripheral shape of the inner and outer peripheral shapes) as the wear progresses in the axial direction. Since the sliding radius on the moving surface is gradually set to the inside, the sliding radius is set to the outside at the initial stage, and the generated sliding torque increases. Then, as the friction plate body wears in the axial direction due to use, the sliding radius gradually becomes inward, so that the acting sliding torque acts in a direction to suppress the generated sliding torque. On the other hand, since the friction coefficient of the material itself increases due to the surface roughness of the sliding surface due to wear, the sliding torque acts in a direction to increase. As described above, the increase in the sliding torque can be suppressed by the reciprocal action of the inward shift of the sliding radius and the increase in the friction coefficient of the material itself, and the increase ratio with the initial sliding torque can be reduced. As a result, it is possible to suppress an increase in sliding torque regardless of the progress of wear.

Therefore, when this friction plate is applied to a clutch disc, power transmission at the time of connection is always ensured, and the performance of the clutch disc is improved.

[Brief description of the drawings]

FIG. 1 is a half sectional view of a friction washer as a friction plate according to one embodiment of the present invention.

FIG. 2 is an overall sectional view of a clutch disk to which the friction washer of FIG. 1 is applied.

FIG. 3 is an exploded perspective view of the clutch disk shown in FIG. 2;

FIGS. 4A and 4B are cross-sectional views of main parts of a transmission using a clutch disk. FIG. 4A shows a state when the clutch disk is connected, and FIG. 4B shows a state when the clutch disk is disconnected. .

FIG. 5 is a sectional view of a friction washer used for the test.

FIG. 6 is a schematic sectional view of a test apparatus.

FIG. 7 is a sectional view of another shape of the friction washer according to the present invention.

FIG. 8 is a sectional view of another shape of the friction washer according to the present invention.

FIG. 9 is a sectional view of another shape of the friction washer according to the present invention.

FIG. 10 is a sectional view of another shape of the friction washer according to the present invention.

FIG. 11 is a sectional view of another shape of the friction washer according to the present invention.

FIG. 12 is a sectional view of another shape of the friction washer according to the present invention.

FIG. 13 is a half sectional view of a friction washer as a conventional friction plate.

FIG. 14 is an overall sectional view of a clutch disk to which the friction washer of FIG. 13 is applied.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Transmission 2 Clutch disk 3 Spline hub 4 Output shaft 5 Flange 5A Notch for stop pin 5B Window hole 6 Torsion spring 7A, 7B Friction facing 8 Flywheel 9 Pressure plate 10 Cushioning plate 10A Engagement part 11 Facing rivet 12 Cushioning rivet Clutch plate 13A Window hole 13B Eave portion 14 Retinig plate 14A Window hole 14B Eave portion 15 Stop pin 16 Cone spring 17 Friction plate 18 Friction washer (friction plate body) 18A Flat portion 18B Taper portion 18C Sliding surface 19 Withdrawal lever Reference Signs List 20 diaphragm spring 200 test apparatus 201 turntable 202 partner material

Continuation of the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) F16F 15/129 F16F 15/139 F16D 13/00-23/14

Claims (2)

(57) [Claims] 1. A friction plate having a ring-shaped friction plate main body, wherein a sliding radius of a sliding surface of the friction plate main body becomes gradually inward as wear progresses in an axial direction. Friction plate. 2. A friction plate according to claim 1, wherein at least the inner peripheral shape of the inner and outer peripheral shapes of the friction plate main body is such that the sliding radius on the sliding surface is gradually inward as the wear progresses in the axial direction. Item 2. The friction plate according to Item 1.