JP7000972B2 - Seal ring, cross shaft joint and steering device - Google Patents

Description

The present application relates to a seal ring incorporated in a cross shaft joint used for a shaft connecting portion for transmitting the steering force of a steering device, a cross shaft joint provided with the seal ring, and a steering device provided with the cross shaft joint. be.

Conventionally, there is a seal ring that seals a gap formed between a bearing cup of a radial bearing that is externally fitted to the end of a cross shaft constituting a cross shaft joint and a shaft portion of the cross shaft.

Such a seal ring has an elastic seal portion and a reinforcing ring embedded in the elastic seal portion, as in Patent Document 1 below.

Utility Model Registration No. 3041732

When molding the elastic seal portion described in Patent Document 1, it is necessary to position the reinforcing ring inside the mold, but when the entire reinforcing ring is embedded in the elastic seal portion, the reinforcing ring may be brought into contact with the mold. It cannot be done and the moldability is poor.

Further, when a part of the reinforcing ring is brought into contact with the mold for positioning, the elastic seal portion does not adhere to the portion of the reinforcing ring in contact with the mold, and the reinforcing ring is exposed, so that the sealing property may deteriorate. There is.

In view of the above, it is an object of the present invention to provide a seal ring, a cross-shaped shaft joint and a steering device having excellent moldability and sealability.

In order to solve the above problems, the present application has a central portion and four shaft portions extending from the central portion in four directions, respectively, and the central portion is in the radial direction of the shaft portion from the base end of the shaft portion. Used with a cross axis that forms a stepped surface that extends outward
A seal ring that is externally fitted to the shaft portion and is arranged between the radial bearing attached to the tip end portion of the shaft portion and the stepped surface.
With a ring-shaped core metal,
It has an elastic portion fixed to the core metal and has an elastic portion.
The elastic portion has a bearing-side seal lip that contacts the radial bearing over the entire circumference.
The core metal has a positioning portion exposed inward in the radial direction, and has a positioning portion.
The core metal has an inclined portion that passes through the shaft portion in the radial direction and whose inner diameter and outer diameter become smaller toward the radial bearing side in the central axis direction of the shaft portion, and the shaft portion in the central axis direction of the shaft portion. It has a flange portion extending radially outward from the end portion of the inclined portion on the step surface side over the entire circumference.
The inclined portion has a penetrating portion penetrating in the direction of the central axis of the shaft portion.
The elastic portion is fixed to the radial bearing side and the stepped surface side of the inclined portion.
Provided is a seal ring characterized in that a portion of the elastic portion on the radial bearing side and the stepped surface side is integrally formed through the penetration portion.

Preferably , the penetrating portion is a recess recessed from the inside in the radial direction to the outside in the radial direction.

Further, preferably, the penetrating portion is a hole portion.
Further, in order to solve the above-mentioned problems, the present application has a central portion and four shaft portions extending from the central portion in four directions, respectively, and the central portion is from the base end of the shaft portion to the shaft portion. Used with a cross axis that forms a stepped surface that extends outward in the radial direction.
A seal ring that is externally fitted to the shaft portion and is arranged between the radial bearing attached to the tip end portion of the shaft portion and the stepped surface.
With a ring-shaped core metal,
It has an elastic portion fixed to the core metal and has an elastic portion.
The elastic portion has a bearing-side seal lip that contacts the radial bearing over the entire circumference.
The core metal has a positioning portion exposed inward in the radial direction, and has a positioning portion.
The core metal has a cylindrical portion that passes the shaft portion inward in the radial direction and a flange portion that extends radially outward from the cylindrical portion on the stepped surface side in the central axis direction of the shaft portion. Have and
The elastic portion has an inner sealing portion fixed to the inside of the cylindrical portion in the radial direction on the radial bearing side in the central axis direction of the shaft portion.
The cylindrical portion provides a seal ring characterized in that a portion on the stepped surface side in the central axis direction of the shaft portion constitutes the positioning portion.
Further, preferably, the inner seal portion forms an inclined surface whose inner diameter increases as the portion on the stepped surface side approaches the stepped surface side in the central axis direction of the shaft portion.

Further, preferably, the elastic portion has a seal lip on the stepped surface side that protrudes in an annular shape on the stepped surface side.

Further, preferably, the seal lip on the stepped surface side has a shape that spreads outward in the radial direction in a state of being assembled to the cross axis.

Further, preferably, the inclined portions are arranged at substantially equal intervals in the circumferential direction, and have three or more inner ends arranged on the innermost side in the radial direction.

Further, in order to solve the above-mentioned problems, the present application provides a cross-shaped shaft joint characterized by having the above-mentioned seal ring.

Further, in order to solve the above problems, the present application provides a steering device characterized in that the ten o'clock shaft joint is provided.

In view of the above, it is an object of the present invention to provide a seal ring, a cross-shaped shaft joint and a steering device having excellent moldability and sealability.

FIG. 1 is a side view showing a steering device according to an embodiment of the present application. FIG. 2 is a perspective view showing an intermediate shaft and a cross-shaped shaft joint according to an embodiment of the present application. FIG. 3 is a cross-sectional view of a cross shaft, a radial bearing, and a seal ring according to an embodiment of the present application. FIG. 4 is an enlarged cross-sectional view of the periphery of the seal ring according to the first embodiment of the present application. FIG. 5 is a cross-sectional view of the seal ring according to the first embodiment of the present application. FIG. 6A is a plan view showing the core metal of the seal ring according to the first embodiment of the present application. FIG. 6B is a cross-sectional view of the core metal according to the first embodiment of the present application on the XX cut surface shown in FIG. 6A. FIG. 7A is a plan view showing the core metal of the seal ring according to the second embodiment of the present application. FIG. 7 (b) is a cross-sectional view of the seal ring according to the second embodiment of the present application on the YY cut surface shown in FIG. 7 (a). FIG. 8A is a plan view showing the core metal of the seal ring according to the third embodiment of the present application. FIG. 8 (b) is a cross-sectional view of the seal ring according to the third embodiment of the present application on the ZZ cut surface shown in FIG. 8 (a). FIG. 9 is a cross-sectional view of the seal ring according to the fourth embodiment of the present application. FIG. 10 is a cross-sectional view of the seal ring according to the fifth embodiment of the present application. FIG. 11 is an enlarged cross-sectional view of the periphery of the seal ring according to the fifth embodiment of the present application.

Hereinafter, embodiments of the present application will be described with reference to the drawings. FIG. 1 is a side view showing a steering device 100 common to the first to third embodiments of the present application.

As shown in FIG. 1, the steering device 100 includes a steering wheel 1, a steering shaft 2, a steering column 3, a vehicle body side bracket 4, a first cross shaft joint 5, an intermediate shaft 6, and a second. It has a cross shaft joint 7, a pinion gear 8, and a rack shaft 9. The steering wheel 1 is fixed to a steering shaft 2 that transmits its rotation. The steering shaft 2 passes through the inside of the steering column 3 and is rotatably supported by the steering column 3 about the central axis. The steering column 3 is attached to the vehicle body 200 by the vehicle body side bracket 4. The rotation of the steering shaft 2 is transmitted to the intermediate shaft 6 by the first cross shaft joint 5. The rotation of the intermediate shaft 6 is transmitted to the pinion gear 8 by the second cross shaft joint 7. The pinion gear 8 rotates to move the rack shaft 9 in the vehicle width direction. The rack shaft 9 moves a knuckle arm (not shown) via a tie rod (not shown) to steer a front wheel (not shown).

FIG. 2 is a perspective view showing an intermediate shaft 6, a first cross-shaped shaft joint 5, and a second cross-shaped shaft joint 7, which are common to the first to third embodiments of the present application.

The first cross-shaped shaft joint 5 includes a first yoke 11 and a second yoke 12. The second cross-shaped shaft joint 7 includes a third yoke 13 and a fourth yoke 14. The first yoke 11 has a pair of arms 11a formed in a bifurcated shape. The second yoke 12 has a pair of arms 12a formed in a bifurcated shape. The first yoke 11 and the second yoke 12 are connected to each other via a pair of arms 11a and a cross axis 16 described later held by the pair of arms 12a. Similarly, the third yoke 13 and the fourth yoke 14 are also connected by a cross axis 16 described later, which is held by a pair of arms 13a and a pair of arms 14a.

FIG. 3 is a cross-sectional view of a cross shaft 16, a radial bearing 21, and a seal ring 26 common to the first to third embodiments of the present application. A cross section cut in a direction perpendicular to the central axis of the intermediate shaft 6 is shown.

The cross-shaped shaft 16 has a central portion 17 and four columnar shaft portions 18 extending from the central portion 17 in four directions, respectively. Specifically, the cross axis 16 includes a first shaft portion 18 extending in one direction from the central portion 17, and a first shaft portion 18 and a first shaft portion 18 having a common central axis with the first shaft portion 18. A second shaft portion 18 extending to the opposite side, a third shaft portion 18 extending from the center portion 17 in a direction perpendicular to the first and second shaft portions 18, and a third shaft portion 18 and a center. It has a fourth shaft portion 18 extending from the central portion 17 to the side opposite to the third shaft portion 18 with a common axis line. Since the configuration around the shaft portion 18 is common to the four shaft portions 18, only one location will be described, and the description of the configuration around the other shaft portions 18 will be omitted. A radial bearing 21 is fitted on the tip of the shaft portion 18. As the radial bearing 21, a needle bearing can be used. The radial bearing 21 has a bearing cup 22 and a roller 23. The bearing cup 22 is fitted in the circular holes formed in the pair of arms 11a to 14a of the yokes 11 to 14 described above. A plurality of rollers 23 are arranged between the bearing cup 22 and the shaft portion 18 of the cross shaft 16 in a direction substantially parallel to the shaft portion 18 in the circumferential direction.

An insertion hole 18a is formed in the central portion of the shaft portion 18 from the tip end side toward the base portion side. A synthetic resin pin 24 is inserted inside the insertion hole 18a. A seal ring 26 is fitted on the base of the shaft portion 18. The seal ring 26 prevents foreign matter from entering the radial bearing 21 through the gap between the bearing cup 22 and the shaft portion 18. The pin 24 is interposed between the bearing cup 22 and the shaft portion 18 to prevent the bearing cup 22 from moving toward the base portion of the shaft portion 18. As a result, it is possible to prevent the seal ring 26 from being compressed by the bearing cup 22 and impairing the sealing property. The seal ring 26 may not be provided in the cross-shaped shaft joint provided in the vehicle interior as in the first cross-shaped shaft joint 5 shown in FIG.

FIG. 4 is an enlarged cross-sectional view of the periphery of the seal ring 26 according to the embodiment of the present application. The portion shown in FIG. 4 has a similar cross-sectional shape over the entire circumference.

The seal ring 26 has a core metal 127 and an elastic portion 28. The core metal 127 is made of metal and has a ring shape. The elastic portion 28 is made of an elastomer and is fixed to the core metal 127. The elastic portion 28 also has a circular ring shape. The central portion 17 of the cross shaft 16 has a larger dimension than the shaft portion 18 in the radial direction of the shaft portion 18, and forms a stepped surface 17a extending radially outward from the base end of the shaft portion 18. There is. The step surface 17a is arranged at a substantially right angle to the central axis of the shaft portion 18. The elastic portion 28 comes into contact with the bearing cup 22 and the stepped surface 17a to prevent foreign matter such as muddy water from entering the bearing cup 22.

(First Embodiment)
FIG. 5 is a cross-sectional view of the seal ring 26 according to the first embodiment of the present application. The seal ring 26 has a similar cross-sectional shape over the entire circumference.

The core metal 127 can be formed by bending a metal plate. The core metal 127 is arranged inside in the radial direction, and has a conical inclined portion 127a whose inner diameter and outer diameter become smaller toward the radial bearing 21 side in the central axis direction of the shaft portion 18, and the central axis of the shaft portion 18. It has a flange portion 127b protruding radially outward from the end portion of the inclined portion 127a on the stepped surface 17a side in the direction over the entire circumference.

The elastic portion 28 has a cross-sectional shape shown in FIG. 5 in a natural state where it is not attached to the cross shaft 16. The elastic portion 28 includes a main body 29, a first seal lip 31 on the bearing side, a second seal lip 32 on the bearing side, a third seal lip 33 on the bearing side, and a fourth seal lip 33 on the stepped surface 17a side. It has a seal lip 34. The main body 29 of the elastic portion 28 is fixed to the core metal 127 except for the inner end 127c in the radial direction of the inclined portion 127a and the surface of the flange portion 127b on the stepped surface 17a side in the central axis direction of the shaft portion 18. .. The exposed portion of the core metal 127 to which the main body 29 is not fixed can be used to contact the core metal 127 with the mold when molding the elastic portion 28 to position the core metal 127. In particular, the exposed portion of the radial inner end 127c of the inclined portion 127a constitutes a positioning portion that can be used for the automatic centering of the core metal 127 by hitting the mold at the time of molding the elastic portion 28.

The main body 29 of the elastic portion 28 extends radially outward of the shaft portion 18 from the core metal 127 over the entire circumference, and rises toward the radial bearing 21 side (upper side in FIG. 5) in the central axis direction of the shaft portion 18. The first seal lip 31 projects radially inward over the entire circumference from the portion of the main body 29 located closest to the radial bearing 21 in the central axis direction of the shaft portion 18. As shown in FIG. 4, the first seal lip 31 is pressed against the outer peripheral surface of the bearing cup 22.

The second seal lip 32 projects radially inward from the portion of the main body 29 near the first seal lip 31 between the core metal 127 and the first seal lip 31. The second seal lip 32 has a conical surface shape that is inclined with respect to the central axis so that the inner diameter and the outer diameter become smaller toward the radial bearing 21 side in the direction of the central axis of the shaft portion 18. As shown in FIG. 4, the second seal lip 32 is pressed against the outer peripheral surface of the bearing cup 22 of the radial bearing 21.

The third seal lip 33 projects from the portion of the main body 29 on the radial bearing 21 side of the core metal 127 in the central axis direction of the shaft portion 18 toward the radial bearing 21 over the entire circumference. The third seal lip 33 has a conical surface shape that is inclined with respect to the central axis so that the inner diameter and the outer diameter increase toward the radial bearing 21 side in the axial direction. As shown in FIG. 4, the third seal lip 33 is pressed against the inner curved portion 22a of the bearing cup 22.

The fourth seal lip 34 on the stepped surface 17a side is annular from the elastic body 28 on the stepped surface 17a side in the central axis direction of the shaft portion 18 to the central portion 17 side (lower side of FIG. 5) of the cross shaft 16. It stands out. The fourth seal lip 34 on the step surface 17a side is arranged radially outside the flange portion 127b of the core metal 127. The fourth seal lip 34 protrudes toward the center portion 17 of the cross axis 16 from the surface of the flange portion 127b on the step surface 17a side in the direction of the center axis of the shaft portion 18, but as shown in FIG. When attached to the shaft 16, it is elastically deformed and the flange portion 127b comes into contact with the stepped surface 17a. The fourth seal lip 34 may have a shape in which the inner diameter and the outer diameter increase toward the stepped surface 17a in the central axis direction of the shaft portion 18. This makes it possible to prevent the fourth seal lip 34 from being caught between the flange portion 127b and the stepped surface 17a when the seal ring 26 is assembled to the cross shaft 16.

FIG. 6A is a plan view showing the core metal 127 of the seal ring 26 according to the first embodiment of the present application. FIG. 6B is a cross-sectional view of the core metal 127 according to the first embodiment of the present application on the XX cut surface shown in FIG. 6A.

The inclined portion 127a has a plurality of recesses 127e recessed from the inside to the outside in the radial direction at regular intervals in the circumferential direction. The recess 127e forms a penetrating portion that penetrates the inclined portion 127a in the direction of the central axis of the shaft portion 18, and is a step between the elastic portion 28 arranged on the radial bearing 21 side of the inclined portion 127a and the inclined portion 127a. It plays a role of integrating the elastic portion 28 arranged on the surface 17a side. In the present embodiment, the number of recesses 127e is four, but the number of recesses 127e is not limited to this. Further, the size and shape of the recess 127e are not limited to those shown in this embodiment. The recess 127e can be set to any number, size, and shape as long as it serves as a penetrating portion as described above.

(Second Embodiment)
Next, the second embodiment of the present application will be described with reference to FIGS. 7 (a) and 7 (b). FIG. 7A is a plan view showing the core metal 227 of the seal ring according to the second embodiment. FIG. 7 (b) is a cross-sectional view of the seal ring according to the second embodiment on the YY cut surface shown in FIG. 7 (a). In the second embodiment, a part of the shape of the core metal 227 is different from the first embodiment, and the other configurations are the same as those in the first embodiment. Therefore, the description of the same parts as those of the first embodiment will be omitted, and the parts different from those of the first embodiment will be described. For the portion corresponding to the portion of the first embodiment, the reference code of the number obtained by adding "100" to the reference code of the first embodiment is used. For example, the inclined portion of the second embodiment corresponding to the inclined portion 127a of the first embodiment will be described with "227a".

The core metal 227 of the second embodiment forms a plurality of elongated holes 227f long in the circumferential direction in the inclined portion 227a in place of the recess 127e of the first embodiment. The elongated hole 227f forms a penetrating portion that penetrates the inclined portion 227a in the central axis direction of the shaft portion 18, and has a portion of the elastic portion 28 arranged on the radial bearing 21 side and a stepped surface 17a side of the inclined portion 227a. It plays a role of integrating the elastic portions 28 arranged in the above. The penetrating portion is not limited to the elongated hole 227f shown in FIG. 7 as long as it is a hole in which the elastic portion 28 can be integrally formed. For example, in the present embodiment, the number of elongated holes 227f is eight, but the number of elongated holes 227f is not limited to this, and may be seven or less, or nine or more. Further, the size and shape of the elongated hole 227f are not limited to those shown in FIG. 7, and may be a round hole or a square hole.

(Third Embodiment)
Next, the third embodiment of the present application will be described with reference to FIGS. 8 (a) and 8 (b). FIG. 8A is a plan view showing the core metal 327 of the seal ring according to the third embodiment. FIG. 8B is a cross-sectional view of the ZZ cut surface shown in FIG. 8A of the seal ring according to the third embodiment. In the third embodiment, a part of the shape of the core metal 327 is different from that of the first embodiment, and the other configurations are the same as those of the first embodiment. Therefore, the description of the same parts as those of the first embodiment will be omitted, and the parts different from those of the first embodiment will be described. For the portion corresponding to the portion of the first embodiment, the reference code of the number obtained by adding "200" to the reference code of the first embodiment is used. For example, the inclined portion of the third embodiment corresponding to the inclined portion 127a of the first embodiment will be described with "327a".

In the core metal 327 of the third embodiment, instead of the inner end 127c of the first embodiment, the tips of the three protrusions 327g separated at substantially equal intervals in the circumferential direction are the most from the central axis in the radial direction. The inner end 327c at a close position is used. The protruding portion 327g protrudes in a semicircular shape from the radial inner portion of the inclined portion 327a. The inner ends 327c, which are separated at approximately equal intervals in the circumferential direction, are positioned so that the core metal 327 can be automatically centered with higher accuracy by applying it to the mold when molding the elastic portion 28. To configure. If three or more inner ends 327c separated in the circumferential direction can be arranged so that the automatic centering of the core metal 327 can be performed with high accuracy in this way, FIG. 8 (a) shows. The protrusion is not limited to 327 g. For example, the curvature of a part of the curved portion inside the inclined surface 327a in the radial direction may be reduced so as to project inward in the radial direction.

(Fourth Embodiment)
Next, the fourth embodiment of the present application will be described with reference to FIG. FIG. 9 is a cross-sectional view of the seal ring 426 according to the fourth embodiment. In the fourth embodiment, the core metal and a part of the elastic portion are different from the first embodiment, and the other configurations are the same as those in the first embodiment. Therefore, the description of the same parts as those of the first embodiment will be omitted, and the parts different from those of the first embodiment will be described. For the portion corresponding to the portion of the first embodiment, the reference code of the number obtained by adding "400" to the reference code of the first embodiment is used. For example, the core metal of the fourth embodiment corresponding to the core metal 27 of the first embodiment will be described with "427".

The core metal 427 of the fourth embodiment is composed of a cylindrical portion 427h and a flange portion 427b having a common central axis with the seal ring 426. The flange portion 427b extends radially outward from the portion of the cylindrical portion 427h on the stepped surface side (lower side of FIG. 9) of the cross axis over the entire circumference. In the direction of the central axis of the seal ring 426, the inner seal portion 435 is fixed as a part of the elastic portion 428 to the inside in the radial direction of the cylindrical portion 427h on the radial bearing side (upper side in FIG. 9), and the step surface side (step surface side (upper side in FIG. 9)). The portion of the cylindrical portion 427h (lower side of FIG. 9) constitutes the positioning portion 427i exposed inward in the radial direction.

According to the fourth embodiment, when the elastic portion 428 is molded, the positioning portion 427i is applied to the mold, so that the automatic centering of the core metal 427 can be performed with high accuracy.

(Fifth Embodiment)
Next, the fifth embodiment of the present application will be described with reference to FIGS. 10 and 11. FIG. 10 is a cross-sectional view of the seal ring 526 according to the fifth embodiment. FIG. 11 is an enlarged cross-sectional view around the seal ring 526 according to the fifth embodiment. In the fifth embodiment, the core metal and a part of the elastic portion are different from the first embodiment, and the other configurations are the same as those in the first embodiment. Therefore, the description of the same parts as those of the first embodiment will be omitted, and the parts different from those of the first embodiment will be described. For the portion corresponding to the portion of the first embodiment, the reference code of the number obtained by adding "500" to the reference code of the first embodiment is used. For example, "527" is used for the core metal of the fifth embodiment corresponding to the core metal 27 of the first embodiment.

The core metal 527 of the fifth embodiment is composed of a cylindrical portion 527h and a flange portion 527b having a common central axis with the seal ring 526. The flange portion 527b extends radially outward from the portion of the cylindrical portion 527h on the stepped surface 517a side of the cross axis over the entire circumference. In the direction of the central axis of the seal ring 526, the inner seal portion 536 is fixed to the inside of the cylindrical portion 527h on the radial bearing 521 side in the radial direction as a part of the elastic portion 528, and the cylindrical portion 527h on the stepped surface 517a side. The portion constitutes a positioning portion 527i exposed inward in the radial direction. The inner seal portion 536 forms an inclined surface 536a whose inner diameter increases as the step surface 571a side approaches the step surface 571a in the central axis direction of the seal ring 526.

As shown in FIG. 11, the fourth seal lip 534 spreads outward in the radial direction when the seal ring 526 is assembled to the cross axis, and expands outward in the radial direction when assembled to the cross axis. It is configured. This makes it possible to prevent the fourth seal lip 534 from getting caught between the flange portion 527b and the stepped surface 517a when the seal ring 526 is assembled to the cross shaft. As one aspect of such a configuration, the fourth seal lip 534 may have a shape in which the inner diameter and the outer diameter increase toward the stepped surface 517a side in the central axis direction of the shaft portion 518.

According to the fifth embodiment, when the elastic portion 528 is molded, the positioning portion 527i is applied to the mold, so that the self-aligning of the core metal 527 can be performed with high accuracy. Further, since the inner seal portion 536 has the inclined surface 536a, the portion of the mold for molding the inclined surface 536a also becomes the inclined surface. Therefore, when the core metal 527 is set in the mold, the core metal 527 is formed by the inclined surface of the mold. Is easily placed in place.

According to the above embodiment of the present application, it is possible to provide a seal ring, an intermediate shaft and a steering device having excellent moldability and sealability.

The invention of the present application is not limited to the above embodiment. For example, instead of the pin 24, a protrusion protruding toward the shaft portion 18 may be provided at the center of the bottom of the bearing cup 22 facing the end surface of the shaft portion 18, and the shaft portion 18 may not be provided with the insertion hole 18a.

Further, the number of seal lips of the seal ring 26 is not limited to four, and it suffices if there is a seal lip in contact with the central portion 17 of the cross shaft 16 and a seal lip in contact with the bearing cup 22. It may be one or more.

Further, the penetrating portion may include both the recess portion described in the first and third embodiments and the hole portion described in the second embodiment.

1 Steering wheel 2 Steering shaft 3 Steering column 4 Body side bracket 5 First cross shaft joint 6 Intermediate shaft 7 Second cross shaft joint 8 Pinion gear 9 Rack shaft 11 First yoke 12 Second yoke 13 Third Yoke 14 Fourth yoke 11a, 12a, 13a, 14a Pair of arms 16 Cross shaft 17 Center 17a Stepped surface 18 Shaft 18a Insertion hole 21 Radial bearing 22 Bearing cup 23 Roller 24 Pin 26, 426, 526 Seal ring 28, 428, 528 Elastic part 29 Main body 31 First seal lip 32 Second seal lip 33 Third seal lip 34 Fourth seal lip 100 Steering device 127, 227, 327, 427, 527 Core metal 127a, 227a, 327a Inclined part 127b, 227b, 327b, 427b, 527b Bearing part 127c, 327c Inner end 127e, 327e Recessed part 227f Long hole 327g Protruding part 427h, 527h Cylindrical part 435, 536 Inner sealing part 536a Inclined surface 200 Vehicle body

Claims (10)

A cross having a central portion and four shaft portions extending in four directions from the central portion, each of which forms a stepped surface in which the central portion extends radially outward from the base end of the shaft portion. Used with the shaft,
A seal ring that is externally fitted to the shaft portion and is arranged between the radial bearing attached to the tip end portion of the shaft portion and the stepped surface.
With a ring-shaped core metal,
It has an elastic portion fixed to the core metal and has an elastic portion.
The elastic portion has a bearing-side seal lip that contacts the radial bearing over the entire circumference.
The core metal has a positioning portion exposed inward in the radial direction, and has a positioning portion.
The core metal has an inclined portion that passes through the shaft portion in the radial direction and whose inner diameter and outer diameter become smaller toward the radial bearing side in the central axis direction of the shaft portion, and the shaft portion in the central axis direction of the shaft portion. It has a flange portion extending radially outward from the end portion of the inclined portion on the step surface side over the entire circumference.
The inclined portion has a penetrating portion penetrating in the direction of the central axis of the shaft portion.
The elastic portion is fixed to the radial bearing side and the stepped surface side of the inclined portion.
A seal ring characterized in that a portion of the elastic portion on the radial bearing side and the stepped surface side is integrally formed through the penetration portion . The seal ring according to claim 1 , wherein the penetrating portion is a recess recessed from the inside in the radial direction to the outside in the radial direction. The seal ring according to claim 1 , wherein the penetrating portion is a hole portion. A cross having a central portion and four shaft portions extending in four directions from the central portion, each of which forms a stepped surface in which the central portion extends radially outward from the base end of the shaft portion. Used with the shaft,
A seal ring that is externally fitted to the shaft portion and is arranged between the radial bearing attached to the tip end portion of the shaft portion and the stepped surface.
With a ring-shaped core metal,
It has an elastic portion fixed to the core metal and has an elastic portion.
The elastic portion has a bearing-side seal lip that contacts the radial bearing over the entire circumference.
The core metal has a positioning portion exposed inward in the radial direction, and has a positioning portion.
The core metal has a cylindrical portion that passes the shaft portion inward in the radial direction and a flange portion that extends radially outward from the cylindrical portion on the stepped surface side in the central axis direction of the shaft portion. Have and
The elastic portion has an inner sealing portion fixed to the inside of the cylindrical portion in the radial direction on the radial bearing side in the central axis direction of the shaft portion.
The cylindrical portion is a seal ring characterized in that a portion on the stepped surface side in the central axis direction of the shaft portion constitutes the positioning portion. The fourth aspect of the present invention is characterized in that the inner seal portion forms an inclined surface whose inner diameter increases as the portion on the stepped surface side approaches the stepped surface side in the central axis direction of the shaft portion. The described seal ring. The seal ring according to any one of claims 1 to 5 , wherein the elastic portion has a seal lip on the step surface side protruding in an annular shape on the step surface side. The seal ring according to claim 6 , wherein the seal lip on the stepped surface side has a shape that spreads outward in the radial direction in a state of being assembled to the cross axis. The aspect according to any one of claims 1 to 3 , wherein the inclined portions are arranged at substantially equal intervals in the circumferential direction and have three or more inner ends arranged on the innermost side in the radial direction. Seal ring. A cross-shaped shaft joint comprising the seal ring according to any one of claims 1 to 8 . A steering device including the cross-shaped shaft joint according to claim 9 .

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