JP2014092256A - Clutch seal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the durability, particularly the breakage resistance, of film parts which are made of a rubber-like elastic body and components of a clutch seal.SOLUTION: A clutch seal is an annular seal disposed between a clutch plate and a piston pressing the clutch plate in a dry clutch. The clutch seal includes: an intermediate ring between an outer ring and an inner ring which are secured to a clutch housing, the intermediate ring being secured to the piston; and film parts provided between the outer ring and the intermediate ring and between the inner ring and the intermediate ring. The clutch seal is characterized in that the intermediate ring is arranged at the intermediate position of a stroke thereof while being in the initial shape, and the flexible part of the film part has a shape with only one bulge rising toward one side in the axial direction.

Description

  The present invention relates to a clutch plate in a dry clutch and an annular clutch seal interposed between pistons that press the clutch plate. The clutch seal of the present invention is used in, for example, a hybrid driving force transmission device or an automatic transmission of a vehicle such as an automobile.

  Conventionally, as shown in FIG. 2, an annular seal 54 interposed between a clutch plate 52 in a dry clutch 51 and a piston 53 that presses the clutch plate 52, an outer ring 56 fixed to a clutch housing 55, and A clutch seal 54 having a middle ring 58 fixed to the piston 53 between the inner rings 57, and having film portions 59, 60 made of rubber-like elastic bodies between the outer ring 56 and the middle ring 58 and between the inner ring 57 and the middle ring 58, respectively. It has been known. The piston 53 is pushed by the hydraulic oil and moves to the right in the figure. When the clutch plate 52 is pressed, the clutch is turned on, and when the piston 53 returns to the left, the clutch is turned off. The seal 54 has a role of sealing the hydraulic oil so as not to enter the clutch plate 52 side.

  In the clutch seal 54, the membrane portions 59, 60 made of rubber-like elastic material are repeatedly elastically deformed with the stroke operation of the piston 53, and a centrifugal force constantly acts on the membrane portions 59, 60 during high-speed rotation. For this reason, efforts must be made to increase the durability of the membrane portions 59 and 60 as much as possible.

JP 2012-52562 A JP 2010-151312 A

  An object of this invention is to provide the clutch seal which can improve the durability of the film | membrane part which consists of a rubber-like elastic body which is a component of a seal in view of the above point.

  To achieve the above object, a clutch seal according to claim 1 of the present invention is an annular seal interposed between a clutch plate in a dry clutch and a piston that presses the clutch plate, and is fixed to the clutch housing. In the clutch seal having a middle ring fixed to the piston between the outer ring and the inner ring, and having a film part made of a rubber-like elastic body between the outer ring and the middle ring and between the inner ring and the middle ring, In the initial shape, the middle ring is disposed at an intermediate position of the stroke, and the flexible portion of the film portion is shaped to have only one bulge portion that bulges in one axial direction.

  The clutch seal according to claim 2 of the present invention is the clutch seal according to claim 1 described above, wherein the outer film portion disposed between the outer ring and the middle ring is an outer side fixed to the outer ring. An outer root portion, a bulge portion, and an inner root portion are integrally formed in this order between the fixing portion and the inner fixing portion fixed to the middle ring, and the outer membrane portion is hung from the top of the bulging portion to the outer root portion. The inner film portion disposed between the inner ring and the middle ring is provided with an inner fixed portion fixed to the inner ring and an outer side fixed to the middle ring. An inner root portion, a bulge portion, and an outer root portion are integrally formed in this order between the fixed portions, and the axial thickness from the top of the bulge portion to the inner root portion gradually increases in the inner membrane portion. Characterized by providing a gradual deformation .

  For example, in a dry clutch of a hybrid driving force transmission device in a vehicle such as an automobile, when a piston is stroked to engage and disengage the clutch, the middle ring of the seal follows this, so that the film portion made of a rubbery elastic body is elastically deformed. The part is elastically deformed between the stroke end and the other end of the middle ring. Therefore, if the middle ring is placed at the stroke end limit with the initial shape of the membrane part, the membrane part will elastically deform over the entire stroke until the middle ring reaches the stroke end limit, so the amount of elastic deformation (strain amount) will be A large internal stress is generated along with this, and this is repeated, so that the film portion fatigues early. On the other hand, in the present invention, since the middle ring is arranged at the middle position of the stroke in the initial shape of the film part, the elasticity of the film part is obtained even when the middle ring moves from the middle position toward one end of the stroke and toward the other end. The amount of deformation can be small and the generated internal stress can be small. Therefore, since the degree of fatigue of the film part is reduced, the durability of the film part is enhanced. The initial shape of the film portion refers to a shape when the film portion is formed by a mold and is not deformed by an external load. In addition, in the present invention, since the flexible part of the film part has a shape including only one bulge part that bulges in one axial direction, this also increases the durability of the film part. The flexible part of the film part is a part excluding the fixing part from the constituent elements of the film part, that is, a part that is elastically deformed during operation.

  In order to further enhance the durability of the film part, the following configuration is preferable.

(1) About the outer membrane part disposed between the outer ring and the middle ring (1-1) The outer membrane part is placed between the outer fixed part fixed to the outer ring and the inner fixed part fixed to the middle ring. The outer root portion, the bulge portion, and the inner root portion are integrally provided in this order.
(1-2) The following configuration is adopted so that strain does not concentrate on the outer base portion when the outer membrane portion is pulled back toward the stroke one end (piston side stroke end).
(1-2-1) The axial thickness from the top of the bulging portion to the outer root portion is a gradually deformed shape that gradually increases from the radially inner side to the outer side.
(1-2-2) The maximum axial direction thickness of the outer base portion is made larger than the thickness of the top portion of the bulge portion (for example, 1.2 to 3 times).
(1-3) Further, the bulge width of the bulge part is made smaller than the stroke amount of the middle ring so as to suppress the deformation of the film part due to the centrifugal force (for example, 1/4 to 2/3).

(2) About the inner membrane part arranged between the inner ring and the middle ring (2-1) This inner membrane part is placed between the inner fixed part fixed to the inner ring and the outer fixed part fixed to the middle ring. The inner root portion, the bulge portion, and the outer root portion are integrally provided in this order.
(2-2) The following configuration is adopted so that strain is not concentrated on the inner base portion when the inner membrane portion is pulled back toward the stroke one end (piston side stroke end).
(2-2-1) The thickness in the axial direction from the top of the bulging part to the inner root is gradually deformed so as to gradually increase from the radially outer side to the inner side.
(2-2-2) The maximum axial thickness of the inner root portion is made larger than the thickness of the top portion of the bulge portion (for example, 1.2 to 3 times).
(2-3) Further, the bulge width of the bulge part is made smaller than the stroke amount of the middle ring so as to suppress the deformation of the film part due to the centrifugal force (for example, 1/4 to 2/3).

  Each of the above configurations (1-1) to (2-3) was derived as a result of earnest research by the inventors of the present application, and according to these configurations, the durability of the film part can be further enhanced. it can. Further, it is preferable that the thickness of the top of the bulge portion in the film portion is as thin as 0.5 to 1.2 mm in actual size.

  The present invention has the following effects.

  That is, in the present invention, as described above, the middle ring is arranged at the stroke middle position in the initial shape of the membrane portion, and the shape having only one bulge portion that bulges the flexible portion of the membrane portion in the axial direction. In addition, by providing the outer and inner membrane portions with a gradually deforming shape in which the axial thickness from the top of the bulge portion to the root portion gradually increases, the durability of the membrane portion made of a rubber-like elastic body is enhanced. be able to.

Sectional drawing of the principal part of the seal for clutches based on the Example of this invention Sectional drawing which shows the mounting state of the seal for clutches which concerns on a prior art example

  Next, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 shows a clutch seal 11 according to an embodiment of the present invention. The clutch seal (bellows seal) 11 according to the embodiment presses the clutch plate 52 (see FIG. 2) in the dry clutch 51 (see FIG. 2) and the clutch plate 52 in a hybrid driving force transmission device of a vehicle such as an automobile. And an outer ring 12 and an inner ring 13 fixed to the clutch housing 55 (see FIG. 2), and an outer ring 12 and an inner ring 13. The middle ring 14 disposed between the outer ring 12 and the middle ring 14, the outer ring portion 15 made of a rubber-like elastic body disposed between the outer ring 12 and the middle ring 14, and the inner ring 13 and the middle ring 14. It has an annular inner membrane portion 16 made of a rubber-like elastic body, and further has the following configuration.

  That is, in order to reduce the amount of distortion of the film portions 15 and 16 at the stroke end position of the middle ring 14, the middle ring 14 is arranged at an intermediate position of the stroke in the initial shape of the film portions 15 and 16. Is set in the middle of the stroke, the initial shapes of the film portions 15 and 16 are set. The initial shapes of the film portions 15 and 16 are shapes when the film portions 15 and 16 are formed by a mold, and are shapes when the strain amount is zero or the minimum value.

  The intermediate position of the stroke in which the middle ring 14 is arranged in the initial shape of the membrane portions 15 and 16 is 25 to 25 in the stroke center position, for example, the stroke from the piston side stroke end of the middle ring 14 to the clutch plate side stroke end. In principle, the position is 75%. However, when the clutch 51 is used for a long time, the clutch plate 52 gradually wears, so that the stroke tends to gradually increase. Therefore, in consideration of the gradually increasing stroke of the middle ring 14 as described above, the initial position is longer toward the clutch plate side stroke end, that is, from the piston side stroke end of the middle ring 14 to the clutch plate side stroke end. It is preferable that it is a position of 25-95% in the stroke over the top, and it is still more preferable that it is a position of 55-90% exceeding 50%. According to these, even if the clutch plate 52 is worn, the middle ring 14 is disposed at an intermediate position of the stroke, so that the elastic deformation amount of the film portions 15 and 16 can be kept small.

  The flexible portions of the film portions 15 and 16 have a shape including only one bulge portion 15d and 16d that bulges in one axial direction (clutch plate side, upward in the drawing).

  Moreover, the film parts 15 and 16 set the bulging parts 15d and 16d formed by R as large as possible in the center part of the film parts 15 and 16 as a measure which reduces distortion as much as possible. is there. The outer diameter of the seal 11 is 110 to 120 mm, and the size of R is, for example, R2.0 to 3.0 mm on the convex surface side (clutch plate side) of the bulging portions 15 d and 16 d, and R1.0 to R on the concave surface side (piston side). 2.0 mm.

  Each of the outer membrane portion 15 and the inner membrane portion 16 has the following configuration.

(1) Regarding the outer membrane portion 15 disposed between the outer ring 12 and the middle ring 14 (1-1) The outer membrane portion 15 is an outer fixed portion (outer peripheral side outer side) fixed (vulcanized and bonded) to the outer ring 12. Between the fixed portion) 15a and the inner fixed portion (outer peripheral side inner fixed portion) 15b fixed (vulcanized and bonded) to the middle ring 14, the outer root portion (outer peripheral side outer root portion) 15c swells in one axial direction. A bulging portion (outer circumferential bulging portion) 15d and an inner root portion (outer circumferential inner root portion) 15e having an arcuate cross-sectional shape are integrally provided in this order.
(1-2) The following configuration is provided so that strain does not concentrate on the outer root portion 15c when the outer membrane portion 15 is pulled back toward one end of the stroke (on the piston side, downward in the drawing).
(1-2-1) Gradual deformation in which the axial thickness from the top of the bulging portion 15d (the top having an arcuate cross section) to the outer root portion 15c gradually increases from the radially inner side to the outer side. It is said that.
(1-2-2) The maximum axial thickness t _{1 of the} outer root portion 15c is 1.2 to 3 times the thickness t ₂ of the top of the bulging portion 15d. The thickness _{t 2} of the top of the bulge portion 15d is a 0.5~1.2mm to scale.
(1-3) Further, to suppress the deformation of the membrane portion 15 by centrifugal force, (axial projection length from the root portion) bulge width of the bulge 15d t ₃ is, the stroke amount of the middle ring 14 1 / 4 to 2/3.

(2) Regarding the inner membrane part 16 disposed between the inner ring 13 and the middle ring 14 (2-1) The inner membrane part 16 is an inner fixed part (inner peripheral side) fixed (vulcanized and bonded) to the inner ring 13 Between the inner fixing portion 16a and the outer fixing portion (inner peripheral side outer fixing portion) 16b fixed (vulcanized and bonded) to the middle ring 14, the inner root portion (inner peripheral side inner root portion) 16c is axially moved to one side. A bulging portion (inner circumferential side bulging portion) 16d and an outer root portion (inner circumferential side outer root portion) 16e having an arcuate cross section that bulges toward each other are integrally formed in this order.
(2-2) The following configuration is provided so that strain does not concentrate on the inner root portion 16c when the inner membrane portion 16 is pulled back toward one end of the stroke (on the piston side, downward in the drawing).
(2-2-1) Slowly deforming shape in which the axial thickness from the top of the bulging portion 16d (the top having an arcuate cross section) to the inner root portion 16c gradually increases from radially outward to inward. It is said that.
(2-2-2) the maximum axial thickness _{t 4} of the inner root portion 16c, there is a 1.2 to 3 times the thickness _{t 5} of the top of the bulge portion 16d. The thickness _{t 5} of the top of the bulge portion 16d is a 0.5~1.2mm to scale.
(2-3) Further, to suppress the deformation of the membrane portion 16 by centrifugal force, (axial projection length from the root portion) bulge width of the bulge 16d t ₆ is, the stroke amount of the middle ring 14 1 / 4 to 2/3.

Each of the film portions 15 and 16 is formed of a material selected from the following (a) to (f).
(B) Acrylic rubber with improved fatigue and low temperature properties (b) Chloroprene rubber with improved high temperature and oil resistance (c) Silicon rubber with improved oil resistance, rubber strength and fatigue properties (d) High temperature and fatigue properties Nitrile rubber with improved fatigue (e) Hydrogenated nitrile rubber with improved fatigue and low temperature (F) Fluoro rubber with improved fatigue and low temperature

  The outer ring 12, the inner ring 13 and the middle ring 14 are each formed by a press-formed metal ring.

  The outer ring 12 and the inner ring 13 are provided with metal fitting portions 12 a and 13 a that are fitted into the clutch housing 55.

  The outer ring 12 and the inner ring 13 are respectively attached (vulcanized and bonded) with rubber seal portions 15h and 16h that are in close contact with the clutch housing 55. These rubber seal portions 15h and 16h are part of the membrane portions 15 and 16, respectively. Is provided.

  Further, the rubber seal portion 15h attached to the outer ring 12 is a lip-shaped rubber seal portion inclined in one axial direction having a seal directivity.

  In the clutch seal 11 having the above-described configuration, as described above, the middle ring 14 is disposed at an intermediate position of the stroke in the initial shape of the membrane portions 15 and 16, and the flexible portions of the membrane portions 15 and 16 are axially arranged. It is made of a rubber-like elastic body by having a shape including only one bulge portion 15d, 16d that bulges on one side, and by adopting the above configurations (1-1) to (2-3). The durability of the film portions 15 and 16 can be increased. Further, the outer ring 12 and the inner ring 13 are metal-fitted to the clutch housing 55 as a press-molded metal ring, and the rubber seal portions 15h and 16h are provided on the film portions 15 and 16 so that the seal 11 with respect to the clutch housing 55 is provided. It is possible to increase the fixing force and maintain the sealing performance between the clutch housing 55 and the seal 11. Further, by using the lip-shaped rubber seal portion 15h inclined in one axial direction having the seal directionality, it is possible to effectively suppress the piston hydraulic oil from leaking to the clutch plate side.

11 Clutch seal 12 Outer ring 12a, 13a Metal fitting part 13 Inner ring 14 Middle ring 15 Outer membrane part 15a, 16b Outer fixing part 15b, 16a Inner fixing part 15c, 16g Outer root part 15d, 16d Swelling part 15e, 16e Inner Root part 15f, 16f Rubber seal part

Claims (2)

An annular seal interposed between a clutch plate in a dry clutch and a piston that presses the clutch plate, and has an outer ring fixed to the clutch housing and an intermediate ring fixed to the piston between inner rings, In the clutch seal having a film portion made of a rubber-like elastic body between the ring and the middle ring and between the inner ring and the middle ring,
The clutch is characterized in that the middle ring is arranged at an intermediate position of the stroke in the initial shape of the membrane portion, and the flexible portion of the membrane portion is formed in a shape having only one bulge portion that bulges in one axial direction. Seal for. The clutch seal according to claim 1,
The outer membrane portion disposed between the outer ring and the middle ring has an outer root portion, a bulge portion, and an inner root portion between the outer fixing portion fixed to the outer ring and the inner fixing portion fixed to the middle ring. In order to have integrally, in order to gradually increase the axial thickness from the top of the bulge portion to the outer root portion on the outer membrane portion,
The inner membrane portion disposed between the inner ring and the middle ring has an inner root portion, a bulge portion, and an outer root portion between the inner fixed portion fixed to the inner ring and the outer fixed portion fixed to the middle ring. A clutch seal characterized by having a gradually deforming shape in which the axial thickness from the top of the bulge portion to the inner root portion is gradually increased.

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