KR20200029676A - Clutch piston in automatic transmission clutch unit - Google Patents

Abstract

The present invention relates to a clutch piston for an automatic transmission clutch unit. The clutch piston for an automatic transmission clutch unit provides a sealing chamber in the lower part of a disk unit and can ascend or descend in the lower part of a support ring unit and the disk unit of a clutch housing having a holder unit, the disk unit, and the support ring unit. The clutch piston for an automatic transmission clutch unit includes: a piston body inserted into the holder unit, wherein a part of the piston body passes through the lower part of the support ring unit and is extended in a radius direction; a first rib body bonded and fixed to one side of the upper surface of the piston body, wherein the first rib body seals the piston body and the support ring unit; a first frictional force reducing unit fixed to the first rib body and reducing the frictional force of the first rib body about the support ring; a second rib body bonded and fixed to the other side of the upper surface of the piston body, wherein the second rib body seals a gap between the piston body and the holder unit; and a second frictional force reducing unit connected to the second rib body and being in contact with the holder unit with the first rib body, wherein the second frictional force reducing unit reduces the frictional force of the second rib body about the holder unit. According to the present invention, the clutch piston for an automatic transmission clutch unit prevents tilting of the clutch piston and can provide excellent responsiveness. Also, the clutch piston for an automatic transmission clutch unit can prevent the impact of changing speed or vibration and one-sided wear. Therefore, the clutch piston for an automatic transmission clutch unit can improve assemblability and reduce the whole length by reducing an interference rate and having a small cross-section.

Description

Clutch piston in automatic transmission clutch unit

The present invention relates to a clutch piston that enters inside a clutch unit of an automatic transmission, and more particularly, to a clutch piston for an automatic transmission clutch unit having little shift shock due to reduction in friction during operation and excellent responsiveness and improved assembly. will be.

The so-called automatic transmission, which automatically shifts to an appropriate transmission stage according to the driving state of the vehicle, includes a ring gear, a sun gear, a planetary gear, a carrier that constitutes a planetary gear device, and various types of electric means and power shut-off to operate them. Means, hydraulic control system, and the like.

The friction clutch included in the automatic transmission serves to transmit power of the engine to each operation member of the planetary gear set, or to mediate power transmission between the operation members. In addition, the brake serves to stop the working member of the rotating planetary gear set.

In addition, the shift in the automatic transmission is implemented by controlling the clutch and brakes determined according to each shift stage to be engaged or released by the hydraulic control system.

The clutch transmits the power of the engine to the actuating member of the planetary gear set or mediates the power transmission between the actuating members, and its internal configuration takes the form shown in FIG. 1.

1 is a cross-sectional view showing a clutch unit 10 to which the conventional clutch piston 13 is applied.

As shown in Fig. 1, the conventional clutch unit 10 includes a clutch housing 11, a clutch piston 13, a spring 15, and a clutch 17.

The clutch housing 11 is located on the bottom of the outer portion of the disc portion 11k and the disc portion 11k integrally formed at the upper end portion of the holder portion 11h, the holder portion 11h on which the shaft coupling hole 11a is formed. It has a support ring portion (11g) on which the oil inlet (11b) is formed. The shaft coupling hole 11a is a hole into which a shaft (not shown) for transmitting the rotational force of the engine is fitted.

In the clutch housing 11, the outer circumferential surface of the holder portion 11h is the first inward surface 11d, the bottom surface of the disk portion 11k is the third inward surface 11f, and the inner surface of the support ring portion 11g is It is the second inwardly facing surface 11e.

A portion of the clutch piston 13 is fitted in the inner regions of the first, second, and third inward surfaces 11d, 11e, and 11f. The space between the clutch piston 13 and the inwardly facing surfaces 11d, 11e, and 11f constitutes a chamber 11c sealed from the outside. When oil is pressurized into the chamber 11c, the clutch piston 13 descends and pressurizes and transfers the clutch 17 downward, and when the oil is drained, the clutch piston 13 is raised by the action of the spring 15.

The clutch piston 13 (also referred to as a bonded piston seal 'BPS') is installed to be lifted under the disc portion 11k of the clutch housing 11 and upward by a spring 15 It is elastically supported.

The clutch piston 13 is a piston body 13a manufactured by pressing a metal plate, a first sealing lip 13b fixedly fixed to the upper outer surface of the clutch piston 13, and an upper inner surface of the clutch piston 16 It is composed of a second sealing lip (13c) fixed to the adhesive. The first sealing lip 13b is interviewed so as to be slidable to the second inwardly facing surface 11e, and the second sealingly lip 13c is slidable to the first inwardly facing surface 11d and maintains a closed state.

Therefore, when oil is pressurized into the chamber 11c through the oil inlet 11b, the clutch piston 13 is pushed downward to move the clutch 17 under pressure. In addition, as described above, when the oil pressure does not act, the clutch piston 13 is raised again by the action of the spring 15.

By the way, the above-described conventional clutch piston 13, the overall horizontal elevation of the clutch piston 13, due to the imbalance of the frictional force generated during the sliding movement of the first sealing lip 13b and the second sealing lip 13c The movement is not smooth, so it is easily tilted, and the responsiveness of pressing and releasing the clutch 17 is poor.

When the clutch piston 13 is operated in a tilted state, shift shock, vibration, and uneven wear of the first and second sealing lips 13b and 13c are inevitable. In order to solve this problem, when the thicknesses of the first and second sealing lips 13b and 13c are thickened, the frictional force is further increased to increase the response time and increase the overall size.

Korean Patent Publication No. 10-2004-0108185 (Installation structure of clutch piston for automatic transmission) Korean Patent Registration No. 10-0956682 (Clutch piston, clutch having the same and automatic transmission having the clutch) Korean Patent Registration No. 10-1393764 (Piston control device for multi-chamber structure clutch)

The present invention was created to solve the above problems, and since the tilting phenomenon of the clutch piston is prevented, responsiveness is good, shift shock and vibration can be prevented, and abrasion can be prevented. It is an object of the present invention to provide a clutch piston for an automatic transmission clutch unit capable of reducing the overall length.

Clutch piston for an automatic transmission clutch unit of the present invention for achieving the above object, the holder portion is formed with a shaft coupling hole, a disc portion integrally formed on the upper end of the holder portion, a disc portion, the outer surface of the outer portion It is integrally formed on the lower portion of the disc portion and the support ring portion of the clutch housing having a support ring portion formed with an oil inlet, the holder portion and the support ring portion can be elevated while being interviewed, and provides a closed chamber under the disc portion, A piston body fitted to the holder portion and partially extending through the lower portion of the support ring portion in a radial direction; A first lip body fixedly attached to one side of the upper surface of the piston body to be slidably movable on the support ring portion, and sealing a gap between the piston body and the support ring portion; First friction force reducing means fixed to the first lip body and interviewing the support ring portion together with the first lip body, and reducing frictional force of the first lip body against the support ring; A second lip body fixed to the other side of the upper surface of the piston body to be slidable to the holder portion, and sealing a gap between the piston body and the holder portion; It is coupled to the second lip body, and includes a second friction body and second friction force reducing means for interviewing the holder portion to reduce the frictional force of the second lip body against the holder portion.

In addition, the first frictional force reducing means takes the form of a ring having a certain diameter, is an inelastic tilting prevention ring surrounding the first lip body, and the second frictional force reducing means has a form of a ring having a constant diameter. It may be taken, and may be an inelastic tilting prevention ring surrounding the holder.

In addition, the tilting prevention ring may be made of any one of Teflon, acetal, acrylic, bakelite, and polycarbonate.

In addition, the tilting prevention ring, through the first and second lip body, extends to the piston body side to physically contact the piston body, a supporter portion receiving a support force from the piston body may be further formed.

The clutch piston for the automatic transmission clutch unit of the present invention made as described above, since the tilting phenomenon of the clutch piston is prevented, it has good responsiveness, and it is possible to prevent shift wear and vibration as well as wear and tear, and reduce the amount of interference and reduce the cross section. It improves the assembly and allows the battlefield to be reduced.

1 is a cross-sectional view for explaining the problem of the conventional clutch piston.
2 is a cross-sectional view of a clutch piston for an automatic transmission clutch unit according to an embodiment of the present invention.
3 is an enlarged view of part A of FIG. 2.
4 is an enlarged view of part B of FIG. 2.
5 and 6 are partial cross-sectional views showing the structure of another type of anti-tilting ring that can be applied to a clutch piston for an automatic transmission clutch unit according to an embodiment of the present invention.

Hereinafter, one embodiment according to the present invention will be described in more detail with reference to the accompanying drawings.

Basically, the clutch piston 40 according to the present embodiment, which will be described later, has tilting prevention rings 43b and 45b at an interview portion with the clutch housing 11. Tilting prevention rings (43b, 45b), by reducing the friction of the clutch piston 40 against the clutch housing 11, to facilitate the lifting movement of the clutch piston 40 and also serves to prevent the tilting in particular .

The clutch piston 40 of this embodiment, the disk portion (11k), which is integrally formed on the upper end of the holder portion (11h), the holder portion (11h) on which the shaft coupling hole (11a) is formed, the disk portion (11k), the disc In the lower portion of the disk portion 11k and the support ring portion 11g of the clutch housing 11 having the support ring portion 11g, which is integrally formed on the bottom surface of the outer portion of the portion 11k and has an oil inlet 11b, the holder It is possible to elevate in the state of being interviewed with the part and the support ring part, and to provide a closed chamber at the bottom of the disc part, the piston body 41 fitted in the holder part and partially extending in the radial direction through the lower part of the support ring part Wow; A first lip body (43a) fixed to one side of the upper surface of the piston body (41), having an interview to be slidably movable in the support ring portion, and sealing a gap between the piston body and the support ring portion; First friction force reducing means fixed to the first lip body and interviewing the support ring portion together with the first lip body to reduce frictional force of the first lip body against the support ring; A second lip body (45a) fixed to the other side of the upper surface of the piston body, slidable to the holder portion, and sealing a gap between the piston body and the holder portion; It is coupled to the second lip body, and may have a basic structure including a second friction body and a second friction force reducing means for interviewing the holder portion to reduce the frictional force of the second lip body against the holder portion.

Figure 2 is a cross-sectional view showing a clutch piston 40 for an automatic transmission clutch unit 30 according to an embodiment of the present invention, Figure 3 is an enlarged view of part A of Figure 2, Figure 4 is part B of Figure 2 It is an enlarged drawing.

The same reference numerals as the above-mentioned reference numerals refer to the same members having the same function.

As shown, the clutch piston 40 according to the present embodiment is installed to be able to elevate between the clutch housing 11 and the clutch 17, the piston body 41, the first sealing lip 43 , Second sealing lip (45).

The clutch housing 11 is a member that passes a shaft (not shown) of the engine through the shaft coupling hole 11a, and has a holder portion 11h, a disc portion 11k, and a support ring portion 11g. In the following description, the outer circumferential surface of the holder portion 11h (as mentioned above) is the first inward face 11d, the bottom face of the disk portion 11k is the third inward face 11f, and the support ring portion ( The inner circumferential surface of 11g) will be referred to as the second inner surface 11e.

The first, second, and third inward surfaces 11d, 11e, and 11f together with the clutch piston 40 constitute one closed chamber 11c. Thus, for example, when oil is pressed into the chamber 11c through the oil inlet 11b, the clutch piston 40 descends under the pressure of the oil and moves the clutch 17 downward. The description of the clutch housing 11 and the clutch 17 will be omitted because it has been described through FIG. 1.

On the other hand, the clutch piston 40 according to the present embodiment is manufactured by bending a metal plate and adheres to one side of the piston body 41 and the upper surface of the piston body 41 through the holder portion 11h to the center thereof. It has a first sealing lip 43 to be fixed, and a second sealing lip 45 to be adhesively fixed to the other side.

The piston body 41 has a pressing portion 41a extending in a radial direction from the lower portion of the support ring portion 11g. The pressing portion 41a plays a role of pressing and moving the clutch 17 downward when the clutch piston 40 is lowered. The rise of the clutch piston 40 is made by a separate spring (not shown). For example, by installing a spring under the clutch piston 40, the clutch piston 40 is configured to move upward by the elastic force of the spring.

The first sealing lip 43 is composed of a first lip body 43a and a first tilt prevention ring 43b. The first lip body 43a is fixed to the piston body 41 by an adhesive method, and is a rubber member that seals the gap between the piston body 41 and the support ring portion 11g. The material of the first lip body 43a is the same as a general rubber for sealing.

The first lip body 43a is slidable in an interviewed state with respect to the second inwardly facing surface 11e. In other words, it is capable of sliding in close contact with the second inward facing surface 11e. However, even if it is possible to slide, the lip body itself is made of rubber, so the friction force is inevitably exerted.

The first tilting prevention ring 43b is a first friction force reducing means for reducing the frictional force of the first lip body 43a and takes the form of a ring having a certain diameter, and the first lip body 43a With the outer circumferential surface wrapped, the second inwardly facing surface 11e is interviewed together with the first lip body 43a. The first tilt prevention ring 43b can be made of any one of Teflon, acetal, acrylic, bakelite, and polycarbonate.

The first tilting prevention ring 43b is a member having a hardness greater than or equal to, and maintains a horizontal level in an interview with the second inwardly facing surface 11e and moves up and down. The first tilting prevention ring 43b has much less friction with respect to the second inwardly facing surface 11e, compared to the first lip body 43a, and has no deformation, so that the first lip body when the clutch piston 40 is elevated ( It acts as a standard for vertical motion in 43a). In other words, the first lip body 43a is moved in a state supported by the first tilting prevention ring 43b.

In addition, the second sealing lip 45 includes a second lip body 45a and a second tilt preventing ring 45b. The second rib body 45a is a rubber member that is fixed to the piston body 41 by an adhesive method, and seals the gap between the piston body 41 and the holder portion 11h. The material of the second lip body 45a may be configured as the first lip body 43a.

The second lip body 45a is slidable in an interviewed state with respect to the first inwardly facing surface 11d. It is capable of sliding while maintaining close contact with the first inward facing surface 11d. However, even if it is possible to slide (as in the first lip body), since the second lip body 45a itself is made of rubber, frictional force is inevitably exerted.

The second tilting prevention ring 45b is a first frictional force reducing means for reducing the frictional force of the second lip body 45a. The second tilting prevention ring 45b takes the form of a ring having a certain diameter and surrounds the outer circumferential surface of the holder portion 11h. The plane including the first tilt prevention ring 45b is orthogonal to the axial direction of the holder portion 11h. The second tilt prevention ring 45b can also be made of any one of Teflon, acetal, acrylic, bakelite, and polycarbonate.

The second tilting prevention ring 45b maintains a level in an interview with the first inwardly facing surface 11d and moves up and down. Since the second tilting prevention ring 45b has no mechanical deformation due to friction, it supports the vertical movement of the second rib body 45a when the clutch piston 40 is elevated. For example, the second lip body 45a is to move while being supported by the second tilting prevention ring 45b.

As a result, by the action of the first and second tilting prevention rings 43b and 45b, the first and second rib bodies 43a and 45a are not inclined when the clutch piston 40 is elevated and maintain a stable horizontal posture. do. Since there is no tilting phenomenon, it is natural that the abrasion does not occur or cause oil leakage.

5 and 6 are partial cross-sectional views showing the structure of another type of tilt prevention ring that can be applied to the clutch piston 40 for an automatic transmission clutch unit according to an embodiment of the present invention.

Referring to Figure 5, it can be seen that the supporter portion 43c is located behind the first tilting prevention ring 43b. The supporter portion 43c is integral with the first tilting prevention ring 43b and penetrates the first lip body 43a to extend toward the piston body 41 to physically contact the piston body. The supporter part 43c supports the first tilting prevention ring 43b in the direction of the arrow a while being supported by the piston body 41. By applying the supporter portion 43c in this way, there is no fear that the front surface of the first tilting prevention ring 43b will withdraw from the second inward surface 11e.

Also, as shown in FIG. 6, a supporter portion 45c is also formed on the second tilting prevention ring 45b. The supporter portion 45c penetrates through the second lip body 45a and extends toward the piston body 41 to be supported at the end of the piston body 41. The supporter portion 45c supports the second tilting prevention ring 45b in the direction of the arrow a, thereby preventing the second tilting prevention ring 45b from being opened from the first inward facing surface 11d.

As described above, the present invention has been described in detail through specific embodiments, but the present invention is not limited to the above embodiments, and various modifications can be made by those skilled in the art within the scope of the technical spirit of the present invention.

10: Clutch unit 11: Clutch housing 11a: Shaft fitting
11b: Oil outlet 11c: Chamber 11d: First inward surface
11e: 2nd inner side 11f: 3rd inner side 11g: Support ring
11h: Holder 11k: Disk 13: Clutch piston
13a: piston body 13b: first sealing tip 13c: second sealing tip
15: spring 17: clutch 30: clutch unit
40: clutch piston 41: piston body 41a: pressing part
43: first sealing tip 43a: first lip body 43b: first tilting prevention ring
43c: supporter section 45: second sealing tip 45a: second lip body
45b: Second tilt prevention ring 45c: Supporter part

Claims (5)

A disc of a clutch housing having a holder portion in which a shaft coupling hole is formed, a disc portion integrally formed on the upper end of the holder portion and taking the form of a disc, and a support ring portion integrally formed on the bottom surface of the outer portion of the disc portion and having an oil outlet. As the lower portion and the support ring portion, the holder portion and the support ring portion can be moved up and down in an interviewed state to provide a closed chamber under the disc portion,
A piston body fitted to the holder portion and partially extending through the lower portion of the support ring portion in a radial direction;
A first lip body fixedly attached to one side of the upper surface of the piston body to be slidably movable on the support ring portion, and sealing a gap between the piston body and the support ring portion;
First friction force reducing means fixed to the first lip body and interviewing the support ring portion together with the first lip body, and reducing frictional force of the first lip body against the support ring;
A second lip body fixedly attached to the other side of the upper surface of the piston body to be slidable to the holder, and sealing a gap between the piston body and the holder;
A clutch piston for an automatic transmission clutch unit comprising a second friction force reducing means coupled to the second lip body and interviewing the holder portion together with the second lip body to reduce frictional force of the second lip body against the holder portion. According to claim 1,
The first friction force reducing means, taking the form of a ring having a constant diameter, the clutch piston for an automatic transmission clutch unit that is an inelastic tilting prevention ring surrounding the first lip body. According to claim 1,
The second friction force reducing means, taking the form of a ring having a certain diameter, the clutch piston for an automatic transmission clutch unit that is an inelastic tilting prevention ring surrounding the holder portion. The method of claim 2 or 3,
The tilting prevention ring,
Clutch piston for automatic transmission clutch units made of either Teflon, acetal, acrylic, bakelite, or polycarbonate. The method of claim 2 or 3,
The tilting prevention ring,
The clutch piston for the automatic transmission clutch unit further penetrating the first and second lip bodies, extending toward the piston body and physically contacting the piston body, and further comprising a supporter part receiving a supporting force from the piston body.

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