JP2010276187A - Method for manufacturing sealing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a sealing device that can reduce working man-hours while securing the required strength of a piston seal and a cancel plate. <P>SOLUTION: The sealing device includes the piston seal axially moved in a housing by oil pressure to carry out pressing operation of a multiple disc clutch, and the annular cancel plate disposed facing the piston seal. The method for manufacturing the sealing device includes a forging process for forging intermediate materials of the piston seal and cancel plate formed of an annular metal material to obtain roughly formed products of the piston seal and cancel plate respectively, and a cutting process for obtaining the piston seal and cancel plate by forming portions, requiring working accuracy higher than working accuracy in the forging process, of the roughly formed products by cutting. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a method of manufacturing a sealing device used as a clutch piston for an automatic transmission such as an automobile.

An automatic transmission such as an automobile has a power interrupting mechanism having a multi-plate clutch for each of a plurality of planetary gear sets for determining a gear ratio, and each of the power interrupting mechanisms has a multi-plate clutch. A sealing device with the function of a clutch piston for actuating is incorporated.
The sealing device constitutes a hydraulic chamber with a housing provided in the power connection portion, and is disposed on the inner peripheral side of the piston seal that can move in the axial direction within the housing by hydraulic pressure. And an annular cancel plate, and a return spring that abuts between the piston seal and the cancel plate and biases them both in the axial direction. The piston seal and the cancel plate are formed by performing sheet metal pressing using a hot-rolled steel plate, a high-tensile steel plate, or the like (see, for example, Patent Document 1).

JP 2008-256056 A

Since the piston seal and the cancel plate constitute a piston that moves in the axial direction in the housing by the hydraulic pressure in the hydraulic chamber, the shape of the piston seal and the cancel plate is complicated and relatively high accuracy is required. In addition, the piston seal and the cancel plate are required to have an appropriate strength because the hydraulic pressure acts in a state in which the piston seal and the cancel plate are biased in the direction away from each other by the return spring.
On the other hand, when the piston seal and the cancel plate are to be formed by sheet metal pressing as in the above-described conventional example, the shape is complicated, and thus a large number of pressing steps are required to form the final shape. Become. For this reason, enormous man-hours are required to form the piston seal and the cancel plate.
Furthermore, when the piston seal and cancel plate are formed by sheet metal pressing, it is difficult to stably form the thickness of the parts that require strength, or stress and plasticity that repeatedly act in the process of performing many pressing processes. There is also a problem that the fatigue strength of a hot-rolled steel sheet or the like, which is a raw material, decreases due to deformation, and it may be difficult to satisfy the strength required for the piston seal and the cancel plate.
This invention is made | formed in view of such a situation, and it aims at providing the manufacturing method of the sealing device which can reduce a process man-hour, ensuring the required intensity | strength of a piston seal and a cancellation plate. .

  In order to achieve the above object, the present invention includes an annular piston seal that presses and operates the clutch mechanism by moving in the housing in the axial direction by hydraulic pressure, and an annular cancel plate that is disposed to face the piston seal. A method for manufacturing a sealing device for an automatic transmission, wherein the piston seal is made by forging an intermediate material of the piston seal made of an annular metal material and an intermediate material of the cancel plate made of an annular metal material, respectively. Forging process to obtain a rough molding material of the seal and a rough molding material of the cancel plate, and forming a portion of the rough molding material that requires higher processing accuracy than processing accuracy in the forging step by cutting, And a cutting process for obtaining a piston seal and the cancel plate. There.

According to the method of manufacturing a sealing device for an automatic transmission configured as described above, a rough molded material is obtained by forging an intermediate material made of an annular metal material. The number of processing steps required to form the plate can be reduced as compared with the conventional sheet metal pressing.
Furthermore, parts that require higher processing accuracy than forging are formed by cutting after the forging process, so that the parts that require a predetermined strength stably are secured by cutting. Can be formed with high accuracy in the thickness and shape required. As a result, the necessary strength can be secured for the piston seal and the cancel plate as a whole.

  In the manufacturing method of the sealing device, the sealing device further includes a return spring that abuts between the piston seal and the cancel plate and biases both in the axially separating direction. The part formed by the cutting process includes a pressing surface that presses the clutch mechanism in the piston seal, and an abutting part that contacts the return spring in each of the piston seal and the cancel plate. Is preferred.

  In this case, since the pressing force of the return spring acts on the clutch mechanism, the pressing surface and the contact portion that are required to be relatively stronger than other parts are cut by cutting after the forging process. Since it forms, it can form accurately in the thickness and shape which are required in order to ensure required intensity | strength in the said part.

  In the manufacturing method of the sealing device, an annular first seal member that seals between the piston seal and the housing is fixed to the piston seal, and the cancel plate and the piston are fixed to the cancel plate. An annular second seal member that seals between the inner peripheral wall of the seal is fixed, and a first seal member in the piston seal is fixed to a portion formed by cutting in the cutting step. And a second fixing portion to which the second seal member of the cancel plate is fixed.

  In this case, since the first and second sealing members to which the dimensional accuracy is required to secure the sealing performance are also formed by cutting after the forging process, the sealing as the sealing device is performed. Can increase the sex.

  According to the manufacturing method of the sealing device of the present invention, it is possible to reduce the number of processing steps while ensuring the necessary strength of the piston seal and the cancel plate.

It is sectional drawing which shows the power interruption mechanism of the automatic transmission for motor vehicles in which the sealing device manufactured by this invention is used. It is the figure which showed the manufacturing process of the piston seal and cancellation plate of a sealing device. It is sectional drawing of the rough molded product obtained by a forge process, (a) is sectional drawing of the rough molded product of a piston seal, (b) is sectional drawing of the rough molded product of a cancellation plate.

Next, preferred embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a cross-sectional view showing a power interrupt mechanism of an automobile automatic transmission in which a sealing device manufactured according to the present invention is used.
In FIG. 1, a power transmission mechanism 1 includes a multi-plate clutch C for interrupting transmission of power to a planetary gear set (not shown), and a seal having the function of a clutch piston for operating the multi-plate clutch C. The apparatus 10 and the housing 20 which accommodates these inside are provided.
The housing 20 is an annular member formed in a concave cross section that opens to one side in the axial direction by sheet metal press molding or the like using, for example, a hot-rolled steel plate, and the cylinder portion 21 in which the annular sealing device 10 is inserted. And an outer cylindrical portion 22 that extends from one end in the axial direction of the outer peripheral wall 21a of the cylinder portion 21 and accommodates the multi-plate clutch C. The sealing device 10 is disposed inside the cylinder portion 21.

  The sealing device 10 is inserted into the inside of the cylinder portion 21, and is disposed in an axially opposed manner to the annular piston seal 11 that defines the first oil chamber R <b> 1 with the cylinder portion 21. An annular cancel plate 12 and a return spring 13 that abuts between the piston seal 11 and the cancel plate 12 are provided.

  The piston seal 11 is an annular member having a concave cross section formed by hot die forging and cutting using steel for machine structure, for example, and an annular portion 11a facing the bottom wall 21b of the cylinder portion 21. An inner cylindrical portion 11b extending from the inner peripheral edge of the annular portion 11a to the one axial side along the inner peripheral wall 21c of the cylinder portion 21, and an axial direction from the outer peripheral edge of the annular portion 11a along the outer peripheral wall 21a of the cylinder portion 21. And an outer cylindrical portion 11c extending to one side.

An annular first seal member 14 that seals between the piston seal 11 and the cylinder portion 21 is fixed to the piston seal 11. The first seal member 14 is vulcanized and bonded to the side surface of the annular portion 11a on the first oil chamber R1 side using an elastic member such as synthetic rubber, and is formed so as to cover the side surface of the annular portion 11a. 14a, an outer peripheral side seal lip 14b that is in sliding contact with the inner peripheral surface of the outer peripheral wall 21a by extending from the outer peripheral end of the annular portion 11a to the outer peripheral side, and an inner peripheral side from the tip of the inner cylindrical portion 11b. It has an inner peripheral side seal lip 14c that is in sliding contact with the outer peripheral surface of the inner peripheral wall 21c.
The first seal member 14 seals the first oil chamber R <b> 1 by sealing between the piston seal 11 and the cylinder portion 21.

  The inner peripheral wall 21c of the cylinder part 21 is provided with a supply port 21c1 for supplying hydraulic oil to the first oil chamber R1. The piston seal 11 can be reciprocated in the axial direction in the cylinder portion 21 by controlling the hydraulic pressure of the hydraulic oil supplied from the supply port 21c1 to the first oil chamber R1.

  A bent portion 11 d for pressing the multi-plate clutch C is formed at the distal end portion of the outer cylindrical portion 11 c of the piston seal 11. The piston seal 11 reciprocates in the cylinder portion 21 in the axial direction by the hydraulic pressure of the hydraulic oil, thereby pressing the multi-plate clutch C with the pressing surface 11d1 of the bent portion 11d or releasing the pressing. The plate clutch C is operated.

  Similar to the piston seal 11, the cancel plate 12 is an annular member formed by die forging and cutting using steel for machine structure, and the second oil chamber R <b> 2 is formed between the piston seal 11 and the housing 20. Defined. The cancel plate 12 includes a large-diameter annular portion 12a located on the inner peripheral side of the piston seal 11, a small-diameter annular portion 12b located on one end side in the axial direction of the large-diameter annular portion 12a, and a cylindrical portion that connects these in the axial direction. 12c.

The inner peripheral end of the small-diameter annular portion 12b is externally fitted and fixed to the inner cylindrical portion 23 of the housing 20, and the movement to one side in the axial direction is restricted by the stopper 15 fixed to the inner cylindrical portion 23. ing.
An annular second seal member 16 that seals between the cancel plate 12 and the piston seal 11 is fixed to the outer peripheral end of the large-diameter annular portion 12a. The second seal member 16 is vulcanized and bonded to the outer peripheral end portion of the large-diameter annular portion 12a using an elastic member such as synthetic rubber, and extends to the outer peripheral side so that the inner periphery of the outer cylindrical portion 11c of the piston seal 11 can be obtained. It has a seal lip 16a in sliding contact with the surface.
The second seal member 16 seals the second oil chamber R2 by sealing between the cancel plate 12 and the piston seal 11.

  The return spring 13 comes into contact with the contact portion 11e formed on the annular portion 11a of the piston seal 11 and the contact portion 12d formed on the small-diameter annular portion 12b of the cancel plate 12, so that the piston seal 11 and the cancel spring 13 are canceled. It is interposed between the plates 12 and urges them in the direction of separating them in the axial direction. When the release spring 13 is released from the state in which the piston seal 11 moves to one side in the axial direction and presses the multi-plate clutch C, the return spring 13 promptly moves the piston seal 11 to the other side in the axial direction. Move to.

  The multi-plate clutch C is configured by superimposing a large number of friction plates C1, and when pressed by the piston seal 11, the friction plates C1 are pressed and transmit power to the planetary gear set. On the other hand, when the pressing is released, the power transmission is cut off. That is, the sealing device 10 can operate the multi-plate clutch C by the reciprocating movement of the piston seal 11 in the axial direction to intermittently transmit power by the multi-plate clutch C, and can serve as a clutch piston in the power transmission mechanism 1. It has the function of

Next, a method for manufacturing the sealing device 10 will be described.
FIG. 2 is a diagram illustrating a manufacturing process of the piston seal 11 and the cancel plate 12 of the sealing device 10. In FIG. 2, first, rough forming is performed by hot die forging an intermediate material in which mechanical structural steel is formed into an annular shape of a predetermined dimension, and a rough molded product of the piston seal 11 (cancelling plate 12) is obtained (step S1). , Forging process).

3 is a cross-sectional view of a roughly molded product obtained in the forging process, FIG. 3 (a) is a cross-sectional view of the roughly molded product of the piston seal 11, and FIG. 3 (b) is a roughly molded product of the cancel plate 12. FIG.
In the drawing, a rough molded product 111 of the piston seal 11 is a finished product in order to secure a margin for cutting in a later process for a portion that requires higher processing accuracy than the processing accuracy in the die forging. It is formed thick with respect to a predetermined dimension as a certain piston seal 11, and other parts are formed with dimensions as a finished product.
Specifically, the parts that require higher processing accuracy than the processing accuracy in the die forging include a contact portion 11e that the return spring 13 contacts, a pressing surface 11d1 that presses the multi-plate clutch C, and the first seal member 14. Among the fixed portions to be fixed, there are an outer peripheral side end portion of the annular portion 11a where the outer peripheral side seal lip 14b is formed and a distal end portion of the inner cylindrical portion 11b where the inner peripheral side seal lip 14c is formed.

  Since the return spring 13 comes into contact with the contact portion 11e, a predetermined flatness is required, and a stable wall thickness is required in order to stably secure a predetermined strength. For this reason, high processing accuracy is required. Since the pressing surface 11d also presses the multi-plate clutch C, predetermined flatness and stable wall thickness are required, and high processing accuracy is required. The fixed portion of the first seal member 14 is required to have a high dimensional accuracy because the seal lips 14b and 14c that are in sliding contact with the housing 20 are required to have a predetermined dimensional accuracy.

  A rough molded product 111 of the piston seal 11 shown in FIG. 3A presses the multi-plate clutch C, a portion corresponding to the contact portion 11e with which the return spring 13 contacts (portion indicated by a broken line H3 in the drawing). A portion corresponding to the pressing surface 11d1 (a portion indicated by a broken line H4 in the drawing), and an outer peripheral side end of the annular portion 11a in which the outer peripheral side seal lip 14b is formed, among the fixed portions to which the first seal member 14 is fixed. A portion corresponding to the portion (portion indicated by a broken line H1 in the drawing) and a portion corresponding to the tip portion of the inner cylindrical portion 11b where the inner peripheral side seal lip 14c is formed (portion indicated by a broken line H2 in the drawing) The shaving margin is secured.

Further, the rough product 112 of the cancel plate 12 shown in FIG. 3 (b) is similar to the rough product 111 of the piston seal 11 with respect to a portion that requires higher processing accuracy than the die forging. The cutting margin for cutting is ensured by this.
Specifically, as the portions that require higher processing accuracy than the processing accuracy in the die forging, the contact portion 12d with which the return spring 13 contacts, the fixing portion to which the second seal member 16 is fixed, and the housing 20 There is an inner peripheral surface of a small-diameter annular portion 12b that is externally fitted to the inner cylindrical portion 23.

  The abutting portion 12d and the fixing portion to which the second seal member 16 is fixed are required to have high processing accuracy for the same reason as the piston seal 11. Since the inner peripheral surface of the small-diameter annular portion 12b is externally fitted to the inner cylindrical portion 23 of the housing 20, high processing accuracy is required.

  In the roughly molded product 112 of the cancel plate 12 shown in FIG. 3B, a portion corresponding to the contact portion 12d with which the return spring 13 abuts (a portion indicated by a broken line H5 in the drawing) and the second seal member 16 are fixed. A portion corresponding to a fixed portion (a portion indicated by a broken line H6 in the drawing) and a portion corresponding to the inner peripheral surface of the small-diameter annular portion 12b fitted to the inner cylindrical portion 23 of the housing 20 (a broken line in the drawing). For the portion indicated by H7, a margin for cutting is secured.

Returning to FIG. 2, after obtaining a rough molded product by the forging process, cutting is performed on the rough molded product (step S2, cutting process).
In the cutting process, each part that requires the above-described high processing accuracy is formed by cutting the rough molded product. As a result, the piston seal 11 and the cancel plate 12 can be obtained.

  According to the manufacturing method of the sealing device for an automatic transmission configured as described above, the rough molded products 111 and 112 are obtained by forging an intermediate material made of an annular metal material. The number of processing steps required to form the seal 11 and the cancel plate 12 can be reduced as compared with the conventional sheet metal press processing.

Furthermore, parts that require higher processing accuracy than forging are formed by cutting after the forging process, so that the parts that require a predetermined strength stably are secured by cutting. Can be accurately formed to have the necessary thickness and shape, and as a result, the piston seal and the cancel plate as a whole can have the required strength.
Specifically, in this embodiment, since the multi-plate clutch C is pressed or the urging force of the return spring 13 acts, the pressing surface 11d1 and the abutting portion are required to be relatively stronger than other portions. Since 11e and 12d are formed by cutting after the forging process, they can be accurately formed in the thickness and shape required to ensure the necessary strength in the part.

  In the present embodiment, the first and second sealing members 14 and 16 to which the dimensional accuracy is required in order to ensure the sealing performance are also formed by cutting after the forging process. The dimensional accuracy of the seal lips 14b, 14c, 16a of the seal members 14, 16 can be increased, and the sealing performance as the sealing device can be improved.

The present invention is not limited to the above embodiments. Although the case where rough forming is performed by hot die forging in the forging step has been described in the above embodiment, the rough forming may be performed by warm die forging or cold die forging.
In addition, as the intermediate material, a suitable material (hot forging material, cold forging material) can be selected according to the processing employed in the forging process. In the above embodiment, the steel for machine structure is made annular. Although what was formed was used, aluminum alloy can also be used as an intermediate material.
Furthermore, a sintered body formed by sintering a predetermined raw metal powder can be used as an intermediate material.

DESCRIPTION OF SYMBOLS 10 Sealing device 11 Piston seal 11d1 Pressing surface 11e Contact part 12 Cancel plate 12d Contact part 13 Return spring C Multi-plate clutch

Claims (3)

Method of manufacturing sealing device for automatic transmission comprising annular piston seal that presses and operates clutch mechanism by moving in housing in axial direction by hydraulic pressure, and annular cancel plate arranged opposite to this piston seal Because
By forging the intermediate material of the piston seal made of an annular metal material and the intermediate material of the cancel plate made of an annular metal material, the rough formed material of the piston seal and the rough formed material of the cancel plate are obtained, respectively. Forging process;
A cutting step for obtaining the piston seal and the cancel plate by forming a portion of the rough forming material that requires higher processing accuracy than the processing accuracy in the forging step by cutting. A method for manufacturing a sealing device for an automatic transmission. The sealing device further includes a return spring that abuts between the piston seal and the cancel plate and biases both in the axially separating direction.
The portion formed by cutting in the cutting step includes a pressing surface for pressing the clutch mechanism in the piston seal, and a contact portion with which the return spring contacts each of the piston seal and the cancel plate. The manufacturing method of the sealing device for automatic transmissions of Claim 1. An annular first seal member that seals between the piston seal and the housing is fixed to the piston seal, and the cancel plate has a gap between the cancel plate and the inner peripheral wall of the piston seal. An annular second sealing member for sealing is fixed,
The part formed by the cutting process in the cutting step includes a first fixing part to which the first seal member in the piston seal is fixed, and a second fixing part to which the second seal member in the cancel plate is fixed. The manufacturing method of the sealing device for automatic transmissions of Claim 1 or 2 characterized by the above-mentioned.

Images