JP2015110963A - Disc spring and hydraulic clutch equipped with its disc spring - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a disc spring which prevents the coming-off of a snap ring by decreasing a number of components, and a hydraulic clutch equipped with the disc spring.SOLUTION: A hydraulic clutch 100 has an inner-diameter wall portion 22, an outer-diameter wall portion 24, a clutch drum 20 having an intermediate wall portion 26, a piston 30, and a clutch hub 40. On an outer periphery of the inner-diameter wall portion 22 of the clutch drum 20, a disc spring 10 is fitted. A snap ring 12 is attached adjacent to the disc spring 10, and position in an axial direction of the disc spring 10 is prevented from coming off by the snap ring 12. The disc spring 10 has a plurality of lever portions 16 and slits 18 in a circumferential direction, and is formed with a protrusion 14 by partially folding an inner-diameter side of a part of the lever portion. The protrusion 14 is provided at a position capable of contacting with an outer peripheral side surface 12a of the snap ring 12, so that the snap ring can be prevented from coming off, without a coming-off preventive ring which is a separated body from the snap ring 12.

Description

  The present invention mainly belongs to the technical field of a disc spring used as a return spring for a piston of a hydraulic clutch.

  Some clutches transmit torque using frictional engagement between a friction plate and a mating member. Such a clutch is usually provided with a spring that urges the mating member in a direction of pressing the mating member against the friction plate, or conversely, urges the mating member in a direction of separating the mating member from the friction plate. A disc spring may be used as the spring, and examples thereof include the following.

Japanese Utility Model Publication No. 02-11228 JP 2006-283940 A

  Patent Document 1 discloses a hydraulic clutch having a plurality of friction plates, which urges a piston in a direction in which the pressure plate and the friction plate are separated from each other when the hydraulic pressure is released. One having disc springs arranged in a sheet is disclosed. The disc spring is prevented from coming off by a snap ring mounted on the outer periphery of the input hub adjacent to the disc spring.

  Patent Document 2 discloses a torque transmission device having two disc springs arranged in the axial direction for urging a pressure plate engaged with a friction plate in the direction of the friction plate. The disc spring is also prevented from coming off in the axial direction by a snap ring attached on the outer periphery of the release device adjacent to the disc spring. Further, in order to prevent the snap ring from opening and coming off from the release device as a result of the centrifugal force acting on the snap ring due to the rotation of the release device, a drop-off prevention ring is provided separately.

  If no measures are taken to prevent the snap ring from falling off as in Patent Document 1, the snap ring may come off, which is a problem. On the other hand, if a snap ring and a separate drop prevention ring are provided as in Patent Document 2, the axial compactness is reduced by that amount, and the number of parts increases, resulting in an increase in assembly man-hours and manufacturing costs. There is a problem of increasing.

  SUMMARY OF THE INVENTION In view of the above-described problems of the prior art, it is an object of the present invention to reduce the number of parts to prevent the snap ring from falling off, and to provide a hydraulic clutch having the same.

The present invention relates to a disc spring that is fitted to a rotating shaft and is retained by a snap ring.
The above-mentioned problem has been solved by a disc spring, wherein the disc spring has a projection for preventing the snap ring from falling off.

  According to the present invention, even if the snap ring is opened by the rotation of the rotating shaft, the protrusion provided on one surface of the disc spring comes into contact with the outer peripheral side surface of the snap ring and suppresses further opening of the snap ring. Therefore, it is possible to prevent the snap ring from falling off the rotating shaft. Further, since a conventional drop-off prevention ring and a snap-off prevention ring are unnecessary, it is more compact in the axial direction than that provided with a drop-off prevention ring. Moreover, since the number of parts is small, the number of assembly steps is small, and the manufacturing cost can be reduced.

  Further, by providing three or more protrusions in the circumferential direction of the disc spring, it is possible to improve the reliability of preventing the snap ring from falling off.

  Moreover, if the disc spring of this invention is applied as a return spring of the piston of a hydraulic clutch, it can be set as a hydraulic clutch compact in an axial direction.

The longitudinal cross-sectional view of the radial direction half of the principal part of the hydraulic clutch to which 1st embodiment of this invention is applied. FIG. 2 is a view taken along line 2-2 in FIG. 1. The front view of the radial direction half of the disk spring of 2nd Embodiment of this invention.

  An embodiment of the present invention will be described with reference to FIGS. However, the present invention is not limited to this embodiment.

  FIG. 1 is a longitudinal sectional view of a radial half of a main part of a hydraulic clutch 100 to which a disc spring 10 of the present invention is applied. The hydraulic clutch 100 is vertically symmetric about the center line X. Of course, the disc spring 10 of the present invention can be applied to a clutch or the like using a disc spring as well as the hydraulic clutch 100 described below.

  First, the hydraulic clutch 100 will be described. The hydraulic clutch 100 includes an inner diameter wall portion 22, an outer diameter wall portion 24, a clutch drum 20 having an intermediate wall portion 26, a piston 30, and a clutch hub 40. The clutch drum 20 is connected to the rotation shaft by spline fitting the boss 28 to the rotation shaft (not shown). Therefore, in the case of the hydraulic clutch 100, the inner wall 22 of the clutch drum 20 is connected to the rotation shaft. Can be equated with. A mating member 50 made up of a pressure plate 52, an intermediate plate 54, and an end plate 56 is spline-fitted inside the outer diameter wall portion 24 of the clutch drum 20, and a friction material is stuck between both sides. A friction plate 42 is provided. The friction plate 42 is splined to the clutch hub 40.

  A hydraulic chamber 60 is provided inside the clutch drum 20, and the piston 30 is fitted in the hydraulic chamber 60. A force transmission member 32 is formed integrally with the piston 30, and the force transmission member 32 extends radially outward to a position where it abuts on the pressure plate 52 of the mating member 50, and the mating member engaging portion 34, And a step 36.

  A disc spring 10 is fitted on the outer periphery of the inner diameter wall portion 22 of the clutch drum 20, and a C-shaped snap ring 12 is attached adjacent to the disc spring 10. Thus, the axial position of the disc spring 10 is secured and fixed in a state where a preload is applied by the snap ring 12. Note that the outer peripheral end of the disc spring 10 is in contact with the inner diameter side of the step portion 36 of the force transmission member 32 and urges the force transmission member 32 and the piston 30 toward the hydraulic chamber 60.

  When hydraulic oil is supplied to the hydraulic chamber 60, the piston 30 moves in the axial direction (rightward in FIG. 1), compresses the disc spring 10, and the mating member engaging portion 34 pushes the pressure plate 52, thereby mating the mating spring. The member 50 and the friction plate 42 are frictionally engaged. Thus, torque transmission between the clutch drum 20 and the clutch hub 40 is realized. When the hydraulic pressure due to the hydraulic oil is released, the piston 30 is pushed back toward the hydraulic chamber 60 by the elastic force of the disc spring 10 that is the return spring of the piston 30, and the frictional engagement between the counterpart member 50 and the friction plate 42 is released. The

  Next, prevention of the snap ring 12 from falling off will be described. The snap ring 12 shown in FIG. 1 has a general C shape. As shown in FIG. 2, the disc spring 10 has a plurality of lever portions 16 and slits 18 in the circumferential direction, and a part on the inner diameter side of some lever portions is bent to form a protrusion 14. . The protrusion 14 is provided at a position where it can come into contact with the outer peripheral side surface 12 a of the snap ring 12 attached to the inner diameter wall portion 22 of the clutch drum 20. When the clutch drum 20 rotates and the snap ring 12 is opened by centrifugal force, the outer peripheral side surface 12a of the snap ring 12 comes into contact with the protrusion 14 and the protrusion 14 prevents the snap ring 12 from opening further. Can be prevented from falling off from the inner diameter wall portion 22. This configuration eliminates the need for a separate drop-off prevention ring from the snap ring 12, and thus can be made compact in the axial direction, and the number of assembly steps can be reduced and the manufacturing cost can be reduced.

  As shown in FIG. 2, it is preferable to provide a plurality of protrusions 14 in the circumferential direction. In particular, by providing three or more protrusions 14 in the circumferential direction, the certainty of preventing the snap ring 12 from falling off can be enhanced.

  Moreover, as shown in FIG. 3, you may make it form the processus | protrusion 14a by bend | folding all the inner diameter sides of some lever parts 16 of the disc spring 10a. As a result, the contact area between the protrusion 14a and the outer peripheral side surface 12a (see FIG. 2) of the snap ring 12 can be increased, so that the snap ring 12 can be easily pressed and the snap ring 12 can be prevented from falling off. be able to.

  The protrusions 14 and 14a of the disc springs 10 and 10a shown in FIGS. 2 and 3 are formed by bending a part of the lever portion 16 by pressing, but may be formed by another processing method. Also good. Even when no slit is formed on the inner diameter side of the disc spring, the protrusions can be evenly arranged in the circumferential direction of the disc spring.

  As described above, according to the present invention, the snap ring can be prevented from falling off by the disc spring which is compact in the axial direction and has a small number of parts.

10, 10a Belleville spring
12 Snap ring 14, 14a Protrusion 20 Clutch drum 22 Inner diameter wall (rotating shaft)
24 outer diameter wall portion 30 piston 32 force transmission member 40 clutch hub 42 friction plate 50 mating member 60 hydraulic chamber

Claims (3)

In a Belleville spring that is fitted into a rotating shaft and is retained by a snap ring,
The disc spring has a projection for preventing the snap ring from falling off,
Disc spring.   The disc spring according to claim 1, wherein three or more protrusions are provided in the circumferential direction of the disc spring.   A hydraulic clutch comprising the disc spring according to claim 1 or 2 as a return spring for a piston.

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