JP5119962B2 - Constant velocity joint sealing structure and constant velocity joint sealing method - Google Patents

Description

  The present invention relates to a constant velocity joint sealing structure and a constant velocity joint sealing method.

2. Description of the Related Art Conventionally, there is a constant velocity joint that connects two shafts of a drive shaft and a driven shaft and can transmit torque at a constant speed even when the two shafts are not coaxial. For example, in Patent Document 1, a large-diameter end portion of a joint cover is fitted on the first end portion side of a cylindrical outer race, and the driven shaft comes into contact with the joint cover to form a driving shaft and a driven shaft. There is disclosed a constant velocity joint in which a working angle is limited to prevent a ball or the like disposed between an outer race and an inner race from falling off. In this type of constant velocity joint, as shown in FIG. 6A, a seal member (for example, an O-ring) 73 is interposed between the outer race 71 and the joint cover 72 to fill the inside of the joint. Prevents leakage of grease.
Japanese Utility Model Publication No. 7-1336

  By the way, the joint cover 72 is assembled to the outer race 71 after the large-diameter cylindrical portion 74 of the joint cover 72 is externally fitted to the outer race 71 and then caulked. On the other hand, as shown in FIG. 6B, the seal member 73 is provided in the annular groove 76 of the outer race 71 in a state of partially protruding from the outer peripheral surface 75 of the outer race 71, and is pressed by the joint cover 72. The space between the outer race 71 and the joint cover 72 is sealed. Therefore, when the joint cover 72 is assembled to the outer race 71, for example, the joint cover 72 may be caught by the seal member 73 and cut off. As a result, there arises a problem that the space between the outer race and the joint cover cannot be sealed.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a constant velocity joint sealing structure and a sealing method thereof that can reliably seal between the outer race and the joint cover. There is.

In order to achieve the above object, according to the first aspect of the present invention, there is provided an accommodating portion formed on the outer peripheral surface of the outer race by fitting the large-diameter cylindrical portion of the joint cover to the first end portion side of the cylindrical outer race. A seal structure of a constant velocity joint that seals between the outer race and the joint cover by an annular seal member provided in the outer race, wherein the housing is located closer to the first end than the housing portion in the outer race. A flange portion having a diameter larger than the outer diameter of the seal member in a state provided in the portion is formed, and the housing portion is adjacent to the housing portion and between the housing portion and the flange portion in the outer race. stepped portion of small diameter is formed than the outer diameter of the seal member provided on the sea together with the large-diameter cylindrical portion abuts on the step portion is fitted to the flange portion And gist that swaged to have a pressing portion for pressing continuously over the member the entire circumference.

According to the said structure, since the flange part is formed larger diameter than the outer diameter of the seal member in the state provided in the accommodating part, the joint cover is fitted on the outer race without contacting the seal member. The large-diameter cylindrical portion is caulked so as to have a pressing portion that continuously presses the seal member over the entire circumference after the external fitting, and the space between the outer race and the seal member is sealed. Therefore, when the joint cover is assembled to the outer race, the joint cover is prevented from being cut by being caught by the seal member, and the gap between the outer race and the joint cover can be reliably sealed. Further, since the step portion is formed to have a smaller diameter than the outer diameter of the seal member, the seal member is pressed against the large diameter cylindrical portion by caulking the large diameter cylindrical portion so as to contact the step portion, and the outer race And the seal member are sealed. Therefore, for example, when the large-diameter cylindrical portion is caulked directly against the seal member, the seal member can be prevented from being damaged by caulking, and the assemblability of the joint cover can be improved.

  The invention according to claim 2 is characterized in that, in the seal structure of the constant velocity joint according to claim 1, the large-diameter cylindrical portion is formed so that a part of the seal member is exposed. According to the above configuration, since a part of the seal member is exposed, the seal member can be visually recognized from the outside, unlike the case where the seal member is completely covered as in the related art. Thereby, it is possible to easily find a defective product with an incomplete seal such as a seal member being cut.

  According to a third aspect of the present invention, in the seal structure of the constant velocity joint according to the second aspect, the large-diameter cylindrical portion is such that the seal member is opposite to the first end portion in the axial direction of the outer race. The gist is that the second end portion is formed so as to be exposed over the entire circumference. According to the said structure, since the sealing member is exposed over the perimeter, it can discover reliably the defective product in which sealing is incomplete, such as the sealing member being cut.

According to a fifth aspect of the present invention, in the constant velocity joint seal structure according to any one of the first to third aspects, the distal end of the large-diameter cylindrical portion is bent toward the radially outer side. The gist is that the expanded diameter portion is formed. According to the said structure, since a large diameter cylindrical part is guided to the outer periphery of an outer race by an enlarged diameter part, a joint cover can be easily fitted over. Further, when the distal end side of the large-diameter cylindrical portion presses the seal member (for example, the configuration according to claim 3), the distal end surface of the large-diameter cylindrical portion is not in contact with the seal member due to the enlarged diameter portion. Since the sealing member is pressed only by the inner peripheral surface of the large diameter cylindrical portion, it is possible to prevent the sealing member from being damaged by the large diameter cylindrical portion.

According to a sixth aspect of the present invention, an annular sealing member is provided in a housing portion formed on the outer peripheral surface of the outer race by fitting the large-diameter cylindrical portion of the joint cover to the first end portion side of the cylindrical outer race. The constant velocity joint sealing method for sealing between the outer race and the joint cover, wherein the large-diameter cylindrical portion is formed on the first end side of the outer race before the housing portion is formed. The outer portion of the seal member in the state of being provided in the storage portion is externally fitted to the flange portion, and is formed between the storage portion and the flange portion in the outer race and provided in the storage portion. The gist is to contact the stepped portion having a diameter smaller than the outer diameter of the sealing member in a state and to press the sealing member continuously over the entire circumference.

According to the above configuration, when the joint cover is assembled to the outer race, the joint cover is prevented from being cut by being caught by the seal member, and the gap between the outer race and the joint cover can be reliably sealed. Further, for example, when the large-diameter cylindrical portion is caulked directly against the seal member, the seal member can be prevented from being damaged by caulking, and the assembling property of the joint cover can be improved.

  ADVANTAGE OF THE INVENTION According to this invention, the seal structure of the constant velocity joint which can seal between an outer race and a joint cover reliably, and its sealing method can be provided.

Hereinafter, an embodiment in which the present invention is embodied in a cross groove type constant velocity joint will be described with reference to the drawings.
As shown in FIG. 1, the constant velocity joint 11 includes an outer race 13 connected to the drive shaft 12 and an inner race 15 connected to the driven shaft 14. In addition, the constant velocity joint 11 is interposed between the outer race 13 and the inner race 15, and a plurality of (six in this embodiment) balls 16 that transmit torque therebetween, and the balls 16 are connected to each other. The cage 17 to hold | maintain is provided.

  The outer race 13 has a bottom with an opening on the first end 18 side (right side in FIG. 1) and a closed second end 19 that is opposite to the first end 18 in the direction of the rotation axis L1 of the drive shaft 12. It is formed in a cylindrical shape. The drive shaft 12 is formed integrally with the second end portion 19. A plurality of first ball grooves 21 inclined in opposite directions with respect to the rotation axis L1 are formed on the inner surface 20 of the outer race 13 at equal intervals in the circumferential direction. On the other hand, the inner race 15 is formed in a substantially annular shape, and the driven shaft 14 is splined to the inner periphery thereof. A plurality of second ball grooves 23 inclined in opposite directions with respect to the rotation axis L2 of the driven shaft 14 are formed on the outer surface 22 of the inner race 15 so as to be paired with the first ball grooves 21, respectively. ing. The cage 17 is formed in a substantially annular shape and is disposed between the outer side surface 22 of the inner race 15 and the inner side surface 20 of the outer race 13. In the cage 17, the same number of ball holding windows 24 as the balls 16 are formed at equal intervals in the circumferential direction. Each ball 16 is interposed in the intersection of the first ball groove 21 and the second ball groove 23 while being accommodated in the ball holding window 24 of the cage 17.

  A substantially cylindrical joint cover 25 made of a metal material is fitted on the first end 18 side of the outer race 13, and the joint cover 25 has a bellows-like shape that covers the space between the outer race 13 and the driven shaft 14. Boots 26 are attached. The joint cover 25 includes a large-diameter cylindrical portion 27 fitted on the outer race 13, a small-diameter cylindrical portion 28 having a smaller diameter than the large-diameter cylindrical portion 27, and an intermediate connecting the large-diameter cylindrical portion 27 and the small-diameter cylindrical portion 28. Part 29. In the present embodiment, the large-diameter cylindrical portion 27 is externally fitted to the outer race 13 in a press-fit state, so that rattling is suppressed. The boot 26 is fixed to the outer periphery of the small-diameter cylindrical portion 28 and the driven shaft 14 by fastening bands 30 and 31, respectively. The boot 26 is formed to be easily elastically deformable and stretchable. The outer race 13 has a space between the outer peripheral surface 32 and the large-diameter cylindrical portion 27 sealed by a seal member 34 inserted into an annular groove 33 as a receiving portion formed on the outer peripheral surface 32. The inner part surrounded by is filled with a lubricant such as grease.

  In the constant velocity joint 11 configured as described above, the driven shaft 14 connected to the inner race 15 can swing (tilt) with respect to the outer race 13 through the movement of each ball 16. Further, when the driven shaft 14 abuts on the joint cover 25, the driven shaft 14 is prevented from tilting more than a predetermined angle, and the balls 16 and the like are prevented from falling off the outer race 13. . FIG. 1 shows a state where the tilt angle is 0 °. On the other hand, since the displacement of the ball 16 in the circumferential direction is restrained by the side walls of the first and second ball grooves 21 and 23, the axis of the outer race 13 (drive shaft 12) and the inner race 15 (driven shaft 14). Relative rotation around is restricted. By such a constant velocity joint 11, the drive shaft 12 and the driven shaft 14 are coupled so as to be capable of relative tilting while maintaining constant rotation transmission.

Next, the seal structure between the outer race 13 and the joint cover 25 will be described.
As shown in FIG. 2, the seal member 34 is formed in an annular shape, and is formed in a rectangular section with a long width (length in the direction of the rotation axis L <b> 1, that is, length in the left-right direction in FIG. 2). . A flange portion 41 having a diameter larger than the outer diameter of the seal member 34 inserted in the annular groove 33 is formed on the outer peripheral surface 32 on the first end portion 18 side (right side in FIG. 2) from the annular groove 33. ing. The large-diameter cylindrical portion 27 is caulked so as to have a pressing portion 42 that continuously presses the entire circumference of the seal member 34.

  In the present embodiment, the large-diameter cylindrical portion 27 is configured such that the pressing portion 42 presses the first end portion 18 side (the right side in FIG. 2) of the outer race 13 in the seal member 34 over the entire circumference and the outer race in the seal member 34. 13 is formed so that the second end portion 19 side (left side in FIG. 2) is exposed. A stepped portion 43 adjacent to the annular groove 33 and having a smaller diameter than the outer diameter of the seal member 34 inserted into the annular groove 33 is formed between the annular groove 33 and the flange portion 41 on the outer peripheral surface 32 of the outer race 13. The large-diameter cylindrical portion 27 is caulked so as to contact the stepped portion 43. Furthermore, a diameter-expanded portion 44 that is bent outward in the radial direction is formed at the tip of the large-diameter cylindrical portion 27.

Next, a sealing method between the outer race 13 and the joint cover 25 will be described.
First, the seal member 34 is inserted into the annular groove 33 of the outer race 13. Subsequently, as shown in FIG. 3, the joint cover 25 is assembled to the outer race 13 without contacting the seal member 34 by externally fitting the large-diameter cylindrical portion 27 to the flange portion 41. In the present embodiment, since the large-diameter cylindrical portion 27 is guided to the outer periphery of the outer race 13 by the enlarged-diameter portion 44, the joint cover 25 can be easily fitted over. Then, the large diameter cylindrical portion 27 is caulked so as to contact the stepped portion 43. Then, since the stepped portion 43 is adjacent to the annular groove 33 and is formed to have a smaller diameter than the outer diameter of the seal member 34, the seal member 34 is formed by the large-diameter cylindrical portion 27 (pressing portion 42) as shown in FIG. Is pressed, and the space between the outer race 13 and the joint cover 25 is sealed.

  Thus, since the joint cover 25 is assembled to the outer race 13 without contacting the seal member 34, the joint cover 25 is prevented from being cut by being caught by the seal member 34, and the outer race 13 and the joint cover 25 are reliably connected. Can be sealed.

As described above, according to the present embodiment, the following effects can be obtained.
(1) The constant velocity joint 11 is an annular groove formed on the outer peripheral surface 32 of the outer race 13 by fitting the large-diameter cylindrical portion 27 of the joint cover 25 to the first end 18 side of the bottomed cylindrical outer race 13. The space between the outer race 13 and the joint cover 25 is sealed by an annular seal member 34 provided at 33. A flange portion 41 having a diameter larger than the outer diameter of the seal member 34 provided in the annular groove 33 is formed closer to the first end portion 18 than the annular groove 33 in the outer race 13. It crimped so that it might have the press part 42 which externally fits to the part 41 and presses the sealing member 34 continuously over the perimeter. As described above, since the flange portion 41 is formed to have a larger diameter than the outer diameter of the seal member 34 provided in the annular groove 33, the joint cover 25 does not come into contact with the seal member 34 and is not attached to the outer race 13. Fitted. And the large diameter cylinder part 27 is crimped so that it may have the press part 42 after external fitting, and the space between the outer race 13 and the joint cover 25 is sealed. Therefore, when the joint cover 25 is assembled to the outer race 13, the joint cover 25 is prevented from being cut by being caught by the seal member 34 and the outer race 13 and the joint cover 25 can be reliably sealed.

  (2) The large-diameter cylindrical portion 27 is formed so as to have the pressing portion 42 that continuously presses the sealing member 34 over the entire circumference, and the second end portion 19 side of the sealing member 34 is exposed over the entire circumference. did. Therefore, since the seal member 34 is exposed over the entire circumference, unlike the case where the seal member is completely covered as in the prior art, a defective product with an imperfect seal such as the seal member 34 being cut off is reliably ensured. Can be found.

  (3) A stepped portion 43 adjacent to the annular groove 33 and having a smaller diameter than the outer diameter of the seal member 34 provided in the annular groove 33 is formed between the annular groove 33 and the flange portion 41 in the outer race 13. The diameter cylinder portion 27 was caulked so as to contact the stepped portion 43. Accordingly, since the stepped portion 43 is formed to have a smaller diameter than the outer diameter of the seal member 34, the seal member 34 is caulked so as to abut on the stepped portion 43, whereby the seal member 34 is The space between the outer race 13 and the seal member 34 is sealed. Therefore, it is possible to prevent the sealing member 34 from being damaged by caulking, as in the case where the large-diameter cylindrical portion 27 is directly caulked against the sealing member, and the assembling property of the joint cover 25 can be improved.

  (4) At the tip of the large-diameter cylindrical portion 27, the enlarged-diameter portion 44 that is bent toward the radially outer side is formed. Therefore, when the distal end side of the large-diameter cylindrical portion 27 presses the seal member 34 as in this embodiment, the distal end surface of the large-diameter cylindrical portion 27 does not contact the seal member 34 due to the enlarged diameter portion 44. Furthermore, since the sealing member 34 is pressed only by the inner peripheral surface of the large diameter cylindrical portion 27, it is possible to prevent the large diameter cylindrical portion 27 from damaging the sealing member 34.

In addition, you may implement this embodiment in the following aspects.
-In this embodiment, although the level | step-difference part 43 was formed between the annular groove 33 and the flange part 41, not only this but the level | step-difference part 43 does not need to be formed, for example, as shown in FIG. The cylindrical portion 51 may be directly caulked against the seal member 52.

  In the present embodiment, the large diameter cylindrical portion 27 is pressed against the first end 18 side of the outer race 13 in the seal member 34 by the pressing portion 42 over the entire circumference, and the second end portion of the outer race in the seal member 34. It was formed so that the 19 side was exposed. However, the present invention is not limited to this, and as shown in FIG. 5, the distal end of the large-diameter cylindrical portion 61 is positioned closer to the second end portion 19 than the annular groove 33, and the seal member 34 is exposed together with the pressing portion 62. An opening window 63 may be formed. Even if it does in this way, since a part of seal member 34 is exposed, it becomes possible to visually recognize the seal member 34 from the outside, and it is possible to easily find defective products such as the seal member being cut. it can.

-In this embodiment, although the enlarged diameter part 44 was formed in the front-end | tip of the large diameter cylinder part 27, it does not need to form not only this but an enlarged diameter part.
-In this embodiment, although the annular groove 33 was formed in the outer peripheral surface 32 of the outer race 13 as an accommodating part, it is not restricted to this, For example, an annular groove is not formed but a sealing member is provided on the surface flush with the outer peripheral surface 32. It may be provided.

  In the present embodiment, the bellows-like boot 26 is provided between the joint cover 25 and the driven shaft 14. However, the invention is not limited thereto, and a U-shaped boot used for a constant velocity joint for a propeller shaft is provided. You may do it.

  -In this embodiment, although this invention was applied to the cross-groove type constant velocity joint, it is not restricted to this, The other constant velocity joint which has a structure which provides a joint cover in the outer periphery of an outer race, and seals between it with a sealing member You may apply to.

Sectional drawing which shows schematic structure of a constant velocity joint. A partial sectional view of a constant velocity joint. A partial cross-sectional view of the outer race before fitting the joint cover, The partial cross section figure of another constant velocity joint. The partial side view of another constant velocity joint. (A) Partial sectional view of a conventional constant velocity joint, (b) Partial sectional view of an outer race before externally fitting a conventional joint cover.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 11 ... Constant velocity joint, 13 ... Outer race, 18 ... 1st end part, 19 ... 2nd end part, 25 ... Joint cover, 27, 51, 61 ... Large diameter cylindrical part, 32 ... Outer peripheral surface, 34, 52 ... Seal 41, flange part, 42, 62 ... pressing part, 43 ... step part, 44 ... enlarged diameter part.

Claims (5)

A large-diameter cylindrical portion of the joint cover is fitted on the first end portion side of the cylindrical outer race, and the outer race and the joint cover are provided by an annular seal member provided in a housing portion formed on the outer peripheral surface of the outer race. A constant velocity joint sealing structure that seals between
A flange portion having a larger diameter than the outer diameter of the seal member provided in the housing portion is formed on the first end portion side of the housing portion in the outer race.
Between the accommodating part and the flange part in the outer race, a step part adjacent to the accommodating part and having a diameter smaller than the outer diameter of the seal member provided in the accommodating part is formed.
The large-diameter cylindrical portion is caulked so as to have a pressing portion that is externally fitted to the flange portion and abuts against the stepped portion and presses the seal member continuously over the entire circumference. Fast joint seal structure.   The constant velocity joint seal structure according to claim 1, wherein the large-diameter cylindrical portion is formed so that a part of the seal member is exposed.   The large-diameter cylindrical portion is formed so that the seal member is exposed over the entire circumference on a second end side opposite to the first end portion in the axial direction of the outer race. The seal structure for a constant velocity joint according to claim 2. The constant velocity joint according to any one of claims 1 to 3 , wherein a diameter-expanded portion bent toward the radially outer side is formed at a tip of the large-diameter cylindrical portion. Seal structure. A large-diameter cylindrical portion of the joint cover is fitted on the first end portion side of the cylindrical outer race, and the outer race and the joint cover are provided by an annular seal member provided in a housing portion formed on the outer peripheral surface of the outer race. A constant velocity joint sealing method for sealing between
Outside said large-diameter cylindrical portion, the flange portion having a larger diameter than the outer diameter of the sealing member in the state provided in the housing's rating accommodating portion before being formed on the first end portion than portion in the outer race Fitted and contacts the stepped portion formed between the housing portion and the flange portion of the outer race and having a smaller diameter than the outer diameter of the seal member in the state of being provided in the housing portion. The constant velocity joint sealing method is characterized in that it is caulked so as to be continuously pressed.

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