Sealing device

Abstract

To inhibit increase in costs and achieve improvement of the quality.SOLUTION: A sealing device 1 includes: an annular piston 100 which is provided in an annular space R0 in a reciprocating manner and switches between power transmission by a clutch 400 and stop of the transmission in conjunction with reciprocating motion according to an oil pressure in an oil pressure chamber R1 formed at one end side of the annular space R0; and a cancel plate 200 which is disposed at the opposite side of the oil pressure chamber R1 across the annular piston 100 and forms a cancel chamber R2 with the annular piston 100. The cancel plate 200 includes: a plate body 210 formed by processing a metal material with a die; a press working part 230 which is formed by pressing an inner periphery side end part 211 at the side in a die removal direction S2 of the plate body 210; and a third seal lip 220 provided at an outer periphery end part 212 of the plate body 210.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a sealing device. [Background technology]

[0002] Conventionally, automatic transmission piston seals have been known as sealing devices used in automatic transmissions for vehicles such as automobiles. In order to operate a multi-plate clutch used for shifting, automatic transmission piston seals reciprocate a piston housed inside a housing to control engagement and release of the multi-plate clutch (see, for example, Patent Document 1). Automatic transmission piston seals are composed of an annular piston that holds pressure and a cancel plate that relieves the centrifugal oil pressure applied to the piston. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2020-180683 A Summary of the Invention [Problem to be solved by the invention]

[0004] Incidentally, when the cancel plate is manufactured by extracting the metal annular plate body from the die, burrs or fracture surfaces may occur at the corners of the inner peripheral end of the plate body. Depending on the shape of the plate body or the conditions of use, the cancel plate may experience the maximum principal stress at the corners of the inner peripheral end of the plate body. In such a case, even if the plate body is below the allowable strength value, stress concentration may occur at the corners, causing the burrs or fracture surfaces to become the starting point of cracks and causing damage. For this reason, the direction in which the plate body is extracted from the die is determined so as to prevent burrs or fracture surfaces from occurring at the corners of the inner peripheral end.

[0005] However, in the conventional sealing device, burrs or fractured surfaces may occur at the corners of the inner peripheral end due to constraints of the manufacturing process. In such cases, in the conventional manufacturing process of the sealing device, the burrs or fractured surfaces are removed by post-processing such as cutting after the plate body is removed from the mold, which causes an increase in costs.

[0006] The present invention has been made in consideration of the above-mentioned problems, and has an object to provide a sealing device that can improve quality while suppressing increases in costs. [Means for solving the problem]

[0007] In order to achieve the above-mentioned object, the sealing device of the present invention comprises an annular piston that is provided so as to be able to move back and forth within an annular space and that switches between transmitting and releasing power by a clutch by pressing or releasing a clutch plate as it moves back and forth in response to the oil pressure in a hydraulic chamber formed on one end side of the annular space, and a cancel plate that is arranged on the opposite side of the hydraulic chamber across the annular piston and forms a cancel chamber between the annular piston and the annular piston that generates oil pressure that offsets the centrifugal oil pressure generated in the hydraulic chamber, and the cancel plate comprises a plate body formed by processing a metal material with a die, a press-processed portion formed by press-processing the inner circumferential end portion of the plate body on the removal direction side of the die, and a seal lip provided on the outer circumferential end portion of the plate body.

[0008] In the sealing device according to one aspect of the present invention, the press-formed portion is an inclined surface formed on an inner peripheral end portion of the plate body on the side facing the removal direction.

[0009] In order to achieve the above object, the manufacturing method of the sealing device according to the present invention is a manufacturing method of a sealing device including: an annular piston that is provided so as to be freely movable back and forth within an annular space, and that switches between transmitting and releasing power by a clutch by pressing or releasing a clutch plate as it moves back and forth in response to the hydraulic pressure within a hydraulic chamber formed on one end side of the annular space; and a cancel plate that is disposed on the opposite side of the hydraulic chamber across the annular piston and forms a cancel chamber between the annular piston and the cancel chamber, which generates hydraulic pressure that offsets the centrifugal hydraulic pressure generated within the hydraulic chamber. In the manufacturing process of the cancel plate, the following steps are carried out: forming a plate body by processing a metal material with a metal die; releasing the plate body from the metal die; and pressing an inner circumferential end portion of the plate body after release in the removal direction of the metal die to form a pressed portion.

[0010] In the step of forming the press-processed portion in the manufacturing method for a sealing device according to one aspect of the present invention, the press-processed portion is formed as an inclined surface formed on the inner peripheral end portion of the plate body on the removal direction side. Effect of the Invention

[0011] According to the sealing device of the present invention, it is possible to improve quality while suppressing an increase in cost. [Brief description of the drawings]

[0012] [Figure 1] 1 is a cross-sectional view showing a schematic configuration of a sealing device according to an embodiment of the present invention. [Diagram 2] 2 is a partially enlarged cross-sectional view showing the sealing device shown in FIG. 1 in the removal direction from the mold. [Diagram 3] 1. FIG. 4 is a partially enlarged cross-sectional view showing another direction in which the sealing device shown in FIG. 1 is removed from the mold. [Figure 4] 2 is a partially enlarged cross-sectional view showing a molding step and a demolding step of a plate body of the cancel plate in the manufacturing method of the sealing device shown in FIG. 1. FIG. [Diagram 5] 2 is a partially enlarged cross-sectional view showing a plate body before a press-processed portion is formed in a manufacturing method of the sealing device shown in FIG. 1. [Figure 6] 2 is a partially enlarged cross-sectional view showing a step of forming a press-processed portion of a plate body of a cancel plate in a manufacturing method of the sealing device shown in FIG. 1. FIG. [Figure 7] 2 is a partially enlarged cross-sectional view showing a plate body after a press-processed portion forming step in the manufacturing method of the sealing device shown in FIG. 1. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0014] FIG. 1 is a cross-sectional view showing a schematic configuration of a sealing device 1 according to an embodiment of the present invention.

[0015] For ease of explanation, in the axial direction indicated by x, the direction of arrow a (see FIG. 1) (one side in the axial direction) is defined as one end side, and the direction of arrow b (see FIG. 1) (the other side in the axial direction) is defined as the other end side. Also, in the direction perpendicular to the axis x (hereinafter also referred to as the "radial direction"), the direction away from the axis x (the direction of arrow c in FIG. 1) is defined as the outer periphery side, and the direction approaching the axis x (the direction of arrow d in FIG. 1) is defined as the inner periphery side.

[0016] As shown in Fig. 1, the sealing device 1 according to the embodiment of the present invention includes an annular piston 100 that is provided reciprocally in an annular space R0 and that switches between transmission and release of power by a clutch 400 by pressing or releasing a clutch plate 410 as the annular piston 100 reciprocates in response to the hydraulic pressure in a hydraulic chamber R1 formed on one end side of the annular space R0, and a cancel plate 200 that is disposed on the opposite side of the hydraulic chamber R1 across the annular piston 100 and forms a cancel chamber R2 between the annular piston 100 and the annular piston 100, which generates hydraulic pressure that offsets the centrifugal hydraulic pressure generated in the hydraulic chamber R1. In the sealing device 1, the cancel plate 200 includes a plate body 210 formed by processing a metal material with a die, a pressed part 230 formed by pressing an inner peripheral end 211 of the plate body 210 on the die removal direction side (arrow S2 direction side shown in Fig. 3), and a third seal lip 220 provided at an outer peripheral end 212 of the plate body 210. The sealing device 1 will be specifically described below.

[0017] The hydraulic actuator according to this embodiment includes an annular cylinder 300, an annular piston 100 provided so as to be capable of reciprocating within an annular space R0 provided in the annular cylinder 300, and a cancel plate 200. The annular piston 100 and the cancel plate 200 are main components of the sealing device 1 as described above.

[0018] The annular piston 100 reciprocates in response to the hydraulic pressure in a hydraulic chamber R1 formed at one end of the annular space R0, thereby pressing or releasing the clutch plate, thereby switching between transmitting and releasing power through the clutch 400. A cancel plate 200 is disposed on the other end of the annular piston 100 opposite the hydraulic chamber R1. Between the cancel plate 200 and the annular piston 100, a cancel chamber R2 is formed that generates hydraulic pressure that offsets the centrifugal hydraulic pressure generated in the hydraulic chamber R1. A plurality of springs 500 are provided between the annular piston 100 and the cancel plate 200 at intervals in the circumferential direction.

[0019] The annular piston 100 includes a metal piston body 110, a seal lip (hereinafter referred to as a "first seal lip 120") provided on the inner peripheral surface side of the piston body 110, and a seal lip (hereinafter referred to as a "second seal lip 130") provided on the outer peripheral surface side of the piston body 110. The piston body 110 is obtained by punching and press-forming a metal plate such as a steel plate. The piston body 110 includes a substantially flat plate-shaped flat plate portion 111, an inner cylinder portion 112 provided on the inner peripheral side of the flat plate portion 111, a flange portion 113 provided at the tip of the inner cylinder portion 112, and an outer cylinder portion 114 provided on the radially outer side of the flat plate portion 111.

[0020] The first seal lip 120 is provided at the tip of the flange portion 113. The second seal lip 130 is provided near the boundary between the flat plate portion 111 and the outer cylinder portion 114. The first seal lip 120 and the second seal lip 130 are made of an elastic body such as rubber. The first seal lip 120 and the second seal lip 130 can be provided integrally with the piston body 110, for example, by insert molding the piston body 110 as an insert part.

[0021] The cancel plate 200 comprises a metal plate body 210, a seal lip (hereinafter referred to as the third seal lip 220) provided at the outer circumferential end 212 of the plate body 210, and a press-formed portion 230 provided at the inner circumferential end 211 of the plate body 210.

[0022] The plate body 210 is obtained by, for example, punching and press-forming a metal plate such as a steel plate using a press die. In addition to the inner peripheral end portion 211 and the press-processed portion 230 described above, the plate body 210 has an outer peripheral end portion 212, an inner peripheral flat portion 213, an outer peripheral flat portion 214, a connecting portion 215, and a snap ring protrusion portion 216. The inner peripheral flat portion 213 is a flat or substantially flat portion extending in a radial direction perpendicular to the axial direction. The outer peripheral flat portion 214 is a flat or substantially flat portion extending in a radial direction and provided on the outer peripheral side of the inner peripheral flat portion 213. The connecting portion 215 is a flat or substantially flat portion parallel or substantially parallel to the axis x between the inner peripheral flat portion 213 and the outer peripheral flat portion 214. The snap ring protrusion 216 is a protrusion formed by punching the inner circumferential flat portion 213 in the axial direction, for example, from one end side to the other end side, at a position near the inner circumferential end portion 211 of the inner circumferential flat portion 213. The snap ring protrusion 216 is a protrusion for positioning the snap ring 313 fixed to the inner circumferential wall surface 310 of the annular cylinder 300. The inner circumferential end portion 211 of the plate body 210 is supported in a positioned state on the inner circumferential wall surface 310 by the snap ring 313 and the snap ring protrusion 216.

[0023] A third seal lip 220 is provided at the outer peripheral end 212 of the plate body 210. The third seal lip 220 is made of an elastic body such as rubber. The third seal lip 220 can be provided integrally with the plate body 210, for example, by insert molding the plate body 210 as an insert part.

[0024] The annular cylinder 300 is provided with a first oil passage 311 for introducing hydraulic pressure to the hydraulic chamber R1 and a second oil passage 312 for introducing hydraulic pressure to the cancel chamber R2. The first oil passage 311 and the second oil passage 312 are both provided as openings in a wall surface 310 on the inner circumferential side of the annular cylinder 300.

[0025] The clutch 400 includes a plurality of clutch plates 410 that are circumferentially engaged with an outer peripheral wall surface 320 of the annular cylinder 300 while being axially movable relative to the outer peripheral wall surface 320 .

[0026] According to the hydraulic actuator configured as above, when the hydraulic pressure in the hydraulic chamber R1 increases due to the hydraulic pressure sent from the first oil passage 311, the annular piston 100 moves toward the cancel plate 200 against the pressing force of the spring 500. As a result, the tip 115 of the outer cylinder portion 114 of the piston body 110 in the annular piston 100 presses the clutch plate 410 downward in FIG. 1. As a result, the clutch plate 410 moves downward in FIG. 1, and the multiple clutch plates 410 are frictionally engaged. As a result, the clutch 400 is in a power transmission state, and the driving torque of the driving shaft (not shown) is transmitted to the driven shaft (not shown) via the annular piston 100 and the clutch 400. Then, when the hydraulic pressure in the hydraulic chamber R1 decreases, the annular piston 100 returns to its original position due to the pressing force of the spring 500, and the pressing state of the annular piston 100 against the clutch plate 410 is released, and the frictional engagement state between the multiple clutch plates 410 is also released. This also releases the transmission of power from the drive shaft to the driven shaft.

[0027] Here, the annular piston 100 and the annular cylinder 300 rotate together with a drive shaft (not shown). Therefore, a centrifugal force of oil acts in the hydraulic chamber R1. Such centrifugal oil pressure can affect the operation of the annular piston 100. However, in this embodiment, oil that generates a centrifugal oil pressure equivalent to the above-mentioned centrifugal oil pressure is supplied from the second oil passage 312 to the cancel chamber R2. Therefore, since both the centrifugal oil pressure in the hydraulic chamber R1 and the centrifugal oil pressure in the cancel chamber R2 act on the annular piston 100, these oil pressures are offset. As a result, the centrifugal oil pressure does not affect the operation of the annular piston 100.

[0028] Fig. 2 is a partially enlarged cross-sectional view showing a direction in which the plate body 210 of the sealing device 1 is removed from a mold. Fig. 3 is a partially enlarged cross-sectional view showing another direction in which the plate body 210 of the sealing device 1 is removed from a mold.

[0029] The plate body 210 will be described with reference to Figs. 2 and 3. In Figs. 2 and 3, arrows S1 and S2 indicate the direction in which the die is removed from the plate body 210 (removal direction). When the plate body 210 is removed from the die in the manufacturing process, burrs may occur at the corners 217 of the inner circumferential end 211 in the removal direction. When the plate body 210 is removed from the die in the manufacturing process, a fracture surface may occur at the inner circumferential end surface 218 in the removal direction of the inner circumferential end 211. When the removal direction of the plate body 210 is the direction shown by arrow S2 in Fig. 3, the corners 217 where burrs occur on one end side in the axial direction and the inner circumferential end surface 218 where a fracture surface occurs are located on one end side in the axial direction. When a principal stress occurs in the plate body 210, stress concentration may occur at the corners 217. When stress concentration occurs at the corners 217, even if the stress is below the allowable strength value, the burrs or fractured surfaces may become the starting points for cracks, causing the plate body 210 to break.

[0030] Thus, the plate body 210 includes a pressed portion 230 formed by pressing on the inner circumferential end portion 211 on the drawing direction S2 side, i.e., on one end side in the axial direction in Fig. 2. The pressed portion 230 is an inclined surface formed on the inner circumferential end portion 211 on the drawing direction S2 side of the plate body 210.

[0031] Next, a manufacturing method of the above-mentioned sealing device 1 will be described.

[0032] Fig. 4 is a partially enlarged cross-sectional view showing a molding process and a demolding process of the plate body 210 of the cancel plate 200 in the manufacturing method of the sealing device 1. As shown in Fig. 4, in the manufacturing process of the plate body 210 of the cancel plate 200, a molding process is performed in which a metal material (metal plate) is processed by a metal die (press die) to form the plate body 210. In the process of manufacturing the cancel plate 200, after the molding process, a demolding process is performed in which the plate body 210 is demolded from the press die in the removal direction S2.

[0033] Fig. 5 is a partially enlarged cross-sectional view showing the plate body 210 before forming the pressed portion 230 in the manufacturing method of the sealing device 1. Also, Fig. 6 is a partially enlarged cross-sectional view showing a forming step of the pressed portion 230 of the plate body 210 of the cancel plate 200 in the manufacturing method of the sealing device 1.

[0034] A pressing step is performed in the process of manufacturing the cancel plate 200. As shown in Fig. 5 and Fig. 6, in the pressing step, a corner portion of the inner peripheral end portion 211 of the plate body 210 after demolding on the removal direction S2 side of the press die is pressed in the direction of the arrow P1 by a pressing surface 601 of a press die 600 through press processing.

[0035] Fig. 7 is a partially enlarged cross-sectional view showing the plate body 210 after a forming step of the pressed portion 230 in the manufacturing method of the sealing device 1. As shown in Fig. 7, in the process of manufacturing the cancel plate 200, the pressed portion 230 is formed by performing a pressing step.

[0036] As described above, according to the sealing device 1 manufactured by the manufacturing method for the sealing device 1 according to the embodiment of the present invention, the corners 217 and part of the inner peripheral end surface 218 at the inner peripheral end 211 on the drawing direction S2 side of the plate body 210 can be crushed by press working together with burrs and fractured surfaces. Furthermore, according to the plate body 210 having the press working part 230, even in a case where a principal stress is generated, the inner peripheral end 211 of the plate body 210 does not have corners, so that stress concentration can be mitigated geometrically. Therefore, according to the press working part 230, burrs and fractured surfaces can be removed without post-processing such as cutting, and damage to the plate body 210 can be prevented.

[0037] In addition, the press-processed portion 230 is not limited to a tapered inclined surface as shown in FIG. 1, and may be, for example, a curved shape (R chamfered) that does not have a right-angle or approximately right-angle corner portion between the inner periphery end face portion 218 and the inner periphery flat portion 213.

[0038] Although the embodiment of the present invention has been described above, the present invention is not limited to the above embodiment of the present invention, and includes all aspects included in the concept of the present invention and the scope of the claims. In addition, each configuration may be appropriately and selectively combined so as to achieve at least a part of the above-mentioned problems and effects. For example, the shape, material, arrangement, size, etc. of each component in the above embodiment may be appropriately changed depending on the specific use mode of the present invention.

[0039] For example, in the manufacturing method of the sealing device 1 according to the present embodiment, in the process of manufacturing the cancellation plate 200, the plate body 210 is formed by press processing using a press die, but the plate body 210 may also be formed by forging. [Explanation of symbols]

[0040] 1...sealing device, 100...annular piston, 110...piston body, 111...flat plate portion, 112...inner cylinder portion, 113...flange portion, 114...outer cylinder portion, 115...tip portion, 120...first seal lip, 130...second seal lip, 200...cancel plate, 210...plate body, 211...inner peripheral end portion, 212...outer peripheral end portion, 213...inner peripheral flat portion, 214...outer peripheral flat portion, 2 Reference Signs List 15...connecting portion, 216...snap ring protrusion, 217...corner portion, 218...inner peripheral end surface portion, 220...third seal lip, 230...pressed portion, 300...annular cylinder, 310...wall surface, 311...first oil passage, 312...second oil passage, 313...snap ring, 320...wall surface, 400...clutch, 410...clutch plate, 500...spring, 600...press die, 601...pressing surface

Claims

1. an annular piston that is provided in the annular space and is capable of reciprocating freely within the annular space, and that reciprocates in response to a hydraulic pressure in a hydraulic chamber formed on one end side of the annular space, thereby pressing or releasing a clutch plate, thereby switching between transmitting and releasing power by the clutch; a cancel plate that is disposed on the opposite side of the hydraulic chamber with the annular piston therebetween and that forms a cancel chamber between the annular piston and the cancel plate to generate hydraulic pressure that cancels out the centrifugal hydraulic pressure generated in the hydraulic chamber; Equipped with The cancellation plate is A plate body formed by processing a metal material using a die; a press-processed portion formed by pressing an inner peripheral end portion of the plate body in the removal direction of the die; a seal lip provided at an outer peripheral end of the plate body; Equipped with Sealing device.

2. The press-processed portion is an inclined surface formed on an inner peripheral end portion of the plate body in the drawing direction. The sealing device according to claim 1 .

3. an annular piston that is provided in the annular space and is capable of reciprocating freely within the annular space, and that reciprocates in response to a hydraulic pressure in a hydraulic chamber formed on one end side of the annular space, thereby pressing or releasing a clutch plate, thereby switching between transmitting and releasing power by the clutch; a cancel plate that is disposed on the opposite side of the hydraulic chamber with the annular piston therebetween and that forms a cancel chamber between the annular piston and the cancel plate to generate hydraulic pressure that cancels out the centrifugal hydraulic pressure generated in the hydraulic chamber; A method for manufacturing a sealing device comprising: In the step of manufacturing the cancellation plate, forming a plate body by processing a metal material with a metal mold; Releasing the plate body from the metal mold; a step of pressing an inner peripheral end portion of the plate body in the removal direction of the metal die after the mold release to form a pressed portion; Execute A method for manufacturing a sealing device.

4. In the step of forming the press-processed portion, the press-processed portion is formed as an inclined surface formed on an inner peripheral end portion of the plate body in the drawing direction. A method for manufacturing the sealing device according to claim 3.

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