Sealing member

Abstract

A sealing member 10 seals a gap between an inner member 5 that rotates coaxially with respect to an outer member 2 and a constant velocity joint 8 that is connected to the inner member, wherein: the sealing member 10 includes a core body 11 having a core body cylindrical portion 12a that is provided on one side in an axial direction and is fitted to an outer peripheral surface 40 of the inner member, and a bent portion 12e that is bent radially inward from an extended end portion 12d that extends from the core body cylindrical portion toward the constant velocity joint on the other side in the axial direction, and a sealing portion 14 made of a resilient body including an annular main body portion 15 and a resilient contacting portion 13 that comes into resilient contact with an outer peripheral surface 8a of the constant velocity joint; the main body portion is fixed to an outer surface 12ea of the bent portion on the other side in the axial direction, and is formed so as to extend farther from the outer surface to the constant velocity joint side; and the resilient contacting portion protrudes from the main body portion toward the outer peripheral surface and is provided so as not to overlap the bent portion in the radial direction.

Description

Sealing member

[0001] The present invention relates to a sealing member that seals between an inner member that rotates coaxially with respect to an outer member and a constant velocity joint connected to the inner member.

[0002] Conventionally, a sealing member that seals between an inner member of a bearing device and a constant velocity joint connected to the inner member has been known. For example, Patent Document 1 and Patent Document 2 disclose a sealing member including a core metal fixed to an inner member and a sealing lip that elastically contacts the outer peripheral surface of a constant velocity joint.

[0003] Japanese Patent Application Laid-Open No. 2012-187957 Japanese Patent Application Laid-Open No. 2021-169833

[0004] The sealing lips disclosed in Patent Document 1 and Patent Document 2 are both located in the vicinity of the end portion on the constant velocity joint side of the core metal and are shaped to be easily elastically deformed. Such a sealing lip has the advantage of being easily elastically deformed following the eccentricity of the constant velocity joint. However, on the other hand, since it is difficult to maintain the reaction force acting on the sealing lip, depending on the degree of eccentricity, the lip may bend with respect to the elastic contact surface, and a gap may occur between the elastic contact surface and the lip, which may affect the sealing performance.

[0005] The present invention has been made in view of the above circumstances, and an object thereof is to provide a sealing member that is less likely to be affected by the sealing performance even when the constant velocity joint is eccentric or the like.

[0006] To achieve the above objective, the present invention provides a sealing member for sealing the space between an inner member that rotates coaxially with respect to an outer member and a constant velocity joint connected to the inner member, comprising: a core body having a cylindrical core portion provided on one axial side and fitted to the outer circumferential surface of the inner member, and a bent portion that bends toward the inner diameter from an extended end extending from the cylindrical core portion toward the constant velocity joint on the other axial side; an annular body portion; and an elastic sealing portion having an elastic contact portion that elastically contacts the outer circumferential surface of the constant velocity joint, wherein the body portion is fixed to the outer surface of the bent portion on the other axial side and extends further toward the constant velocity joint from the outer surface, and the elastic contact portion protrudes from the body portion toward the outer circumferential surface and is provided so as not to overlap radially with the bent portion.

[0007] In the above configuration, the radial dimension of the seal portion may be larger than the radial dimension of the bent portion, and the elastic contact portion may be provided further inward than the inner diameter end of the bent portion. Also in the above configuration, the main body portion may be formed in a rectangular shape in cross-section, and its outer diameter corner portion may be displaced outward as the elastic contact portion makes elastic contact with the outer surface of the constant velocity joint. In this case, the main body portion may have a tapered portion that slopes from the inner diameter corner portion toward the elastic contact portion.

[0008] Because the sealing member of the present invention has the above-described configuration, its sealing performance is less affected even if the constant velocity joint is eccentric or otherwise misaligned.

[0009] This is a schematic cross-sectional view showing an example of a bearing unit to which a sealing member according to one embodiment of the present invention is applied. (a) is a diagram illustrating the process of assembling a constant velocity joint to the bearing unit, and (b) is an enlarged view of part X in Figure 1. This is a cross-sectional view illustrating the state in which the constant velocity joint is eccentric in the bearing unit. (a) and (b) are schematic partial cross-sectional views illustrating a modified example of the sealing member. (a) and (b) are schematic partial cross-sectional views illustrating a modified example of the sealing member. This is a schematic cross-sectional view illustrating a modified example of the sealing member. The results of comparative tests regarding sealing performance are summarized in the table.

[0010] An example of a sealing member according to this embodiment will be described below with reference to the drawings. Note that some of the detailed reference numerals used in other figures have been omitted in some of the figures. Also, in the figures, the sealing portion shown by the dashed line represents the shape in its natural state before elastic deformation.

[0011] The sealing member 10 seals the space between the inner members 5 (3, 4), which rotate coaxially with respect to the outer member 2, and the constant velocity joint 8, which is connected to the inner members 5. The sealing member 10 comprises a core body 11 and a sealing portion 14. The core body 11 has a cylindrical core body portion 12a provided on one axial side and fitted onto the outer circumferential surface 40 of the inner ring member 4, and a bent portion 12e that bends inward from an extended end 12d that extends from the cylindrical core body portion 12a toward the constant velocity joint 8 on the other axial side. The sealing portion 14 has an annular main body portion 15 and an elastic contact portion 13 that elastically contacts the outer circumferential surface 8a of the constant velocity joint 8. The main body portion 15 is fixed to the outer surface 12ea on the other axial side of the bent portion 12e and extends further toward the constant velocity joint 8 from the outer surface 12ea. The elastic contact portion 13 protrudes from the main body portion 15 toward the outer peripheral surface 8a and is provided so as not to overlap radially with the bent portion 12e. A detailed explanation follows below.

[0012] As shown in Figure 1, the bearing unit 1 supports a wheel (not shown) of a vehicle such as an automobile so that it can rotate around an axis. The bearing unit 1 is broadly composed of an outer ring 2 corresponding to the outer member described above, an inner ring 5 corresponding to the inner member described above, and two rows of rolling elements (balls) 6... interposed between the outer ring 2 and the inner ring 5. The inner ring 5 is composed of a hub ring 3 and an inner ring member 4, and the inner ring member 4 is fitted integrally with the vehicle body side of the hub ring 3. The inner ring 5 is rotatable around an axis L relative to the outer ring 2. The outer ring 2 and the inner ring 5 form two members that rotate relative to each other, forming an annular space S. Within the annular space S, the two rows of rolling elements 6... are interposed so that the raceway ring 2a of the outer ring 2, the hub ring 3, and the raceway rings 3a and 4a of the inner ring member 4 can roll, while being held by a retainer 6a. The hub wheel 3 has a cylindrical hub wheel body 3b and a hub flange 3d formed to extend outward from the hub wheel body 3b via a rising base portion 3c. The wheel is attached and fixed by bolts and nuts (not shown) inserted through insertion holes 3e in the hub flange 3d. The inner ring member 4 may be provided such that its vehicle body side end is located closer to the vehicle body than the outer ring 2. The corner of the inner ring member 4 on the vehicle body side has an inward-facing step formed in the circumferential direction, and the outer circumferential surface 40 is composed of two stepped surfaces: a first outer circumferential surface 4b and a second outer circumferential surface 4d (see Figure 2(a), etc.). An end face 4c, which is a radially upright surface, is provided between the first outer circumferential surface 4b and the second outer circumferential surface 4d.

[0013] The hub wheel 3 has a flange-shaped crimped portion 3f, where the vehicle-side end of the hub wheel body 3b is crimped to the vehicle-side end face of the inner ring member 4. The vehicle-side end of this crimped portion 3f is provided with a face spline 3g, which has axial irregularities formed alternately in the circumferential direction. The constant velocity joint 8 is provided with a face spline 8b at the wheel-side end facing the crimped portion 3f in the axial direction, which has irregularities that engage with the irregularities of the face spline 3g of the hub wheel 3. In addition, the radial center of the constant velocity joint 8 is provided with an insertion hole 8c that penetrates axially. This insertion hole 8c is formed as a female screw hole. With the face splines 3g and 8b of the hub wheel 3 and constant velocity joint 8 engaged, a bolt 7 inserted from the wheel side of the hub wheel 3 (hub wheel body 3b) is fastened into the insertion hole 8c of the constant velocity joint 8, thereby connecting the inner wheel 5 (hub wheel 3) and the constant velocity joint 8 with the head of the bolt 7 in contact with the wheel-side end face of the hub wheel 3 (hub wheel body 3b). As a result, the inner wheel 5 (hub wheel 3 and inner wheel member 4) is connected to a drive source (drive transmission unit) not shown via the constant velocity joint 8.

[0014] A sealing device 9 is installed between the wheel-side end of the outer ring 2 and the inner ring 5 (hub ring 3). Additionally, a sealing device 20 is installed between the vehicle-side end of the outer ring 2 and the cylindrical core portion 12a of the seal member 10 fitted to the first outer peripheral surface 4b of the inner ring member 4. These sealing devices 9 and 20 seal both axial sides of the annular space S, preventing the intrusion of foreign matter such as muddy water into the annular space S and preventing the leakage of lubricant (grease, etc.) filled in the annular space S to the outside.

[0015] The configuration and shape of the sealing device 20 are not particularly limited, but as shown in Figures 2(a) and 2(b), it comprises a double-cylindrical slinger member 21, a core member 23 with a substantially L-shaped cross-section that fits inside the inner circumferential surface 2b of the outer ring 2, and an elastic seal lip portion 24 that slides against the slinger member 21. The slinger member 21 has an inner diameter cylindrical portion 21a, a ring portion 21b, and an outer diameter cylindrical portion 21c, and an encoder 22 is provided on the vehicle body side of the ring portion 21b, in which N poles and S poles are magnetized alternately and continuously in the circumferential direction. The encoder 22 is made of magnetic rubber or a plastic magnet, and a detection mechanism is configured that can detect the rotation speed of the inner ring 5, etc., when the encoder 22 faces a magnetic sensor 30 provided on the vehicle body, etc. If the encoder 22 is made of an elastic material such as magnetic rubber, the inner diameter end 22a of the encoder 22 can be elastically brought into contact with the outer circumferential surface 12aa of the core cylindrical portion 12a, thereby preventing foreign matter such as muddy water from entering between the inner diameter cylindrical portion 21a and the outer circumferential surface 12aa.

[0016] The slinger member 21 is assembled by fitting its inner diameter cylindrical portion 21a onto the first outer peripheral surface 4b of the inner ring member 4 with the core cylindrical portion 12a of the seal member 10 interposed between them. Therefore, the seal member 10 is firmly fixed to the inner ring member 4 because the core cylindrical portion 12a is fitted onto the first outer peripheral surface 4b of the inner ring member 4, and the inner diameter cylindrical portion 21a of the slinger member 21 is fitted onto the outer peripheral surface 12aa of the core cylindrical portion 12a.

[0017] The sealing member 10 is an annular member that prevents dust, muddy water, etc. from entering the connection portion between the inner ring 5 and the constant velocity joint 8 (between the face splines 3g and 8b that mesh with each other). As shown in Figures 1 and 2(b), the sealing member 10 is provided so as to cover the outer circumference of the connection portion between the inner ring 5 and the constant velocity joint 8 (face splines 3g and 8b).

[0018] The sealing member 10 comprises a core body 11 and a sealing portion 14. The core body 11 is formed by press-forming a steel plate such as SPCC or SUS, and the portion other than the portion that fits onto the first outer peripheral surface 4b of the inner ring member 4 is provided in a non-contact manner with respect to the inner ring 5 and the constant velocity joint 8. The core body 11 has a core body cylindrical portion 12a, a stepped portion 12b, an extended cylindrical portion 12c, and a bent portion 12e. The core body cylindrical portion 12a is formed in a cylindrical shape that extends in the axial direction and fits onto the first outer peripheral surface 4b of the inner ring member 4. The stepped portion 12b is formed by bending inward from the other axial end of the core body cylindrical portion 12a. The extended cylindrical portion 12c is formed extending from the stepped portion 12b toward the constant velocity joint 8. The bent portion 12e is formed by bending inward from the extended end 12d of the extended cylindrical portion 12c on the constant velocity joint 8 side (vehicle body side). The bent portion 12e is formed with radial dimensions such that it does not contact the constant velocity joint 8 when the core body 11 is mounted on the inner ring member 4, and is configured at a distance from the core body cylindrical portion 12a that is fitted into the inner ring member 4.

[0019] The seal portion 14 is made of rubber or a soft resin material and has an annular body portion 15, a protruding portion 17, and an elastic contact portion 13 that elastically contacts the outer circumferential surface 8a of the constant velocity joint 8. The radial dimension of the seal portion 14 is formed to be larger than the radial dimension of the bent portion 12e, and the elastic contact portion 13 is provided further inward than the inner diameter end 12eb of the bent portion 12e. The body portion 15 of the seal portion 14 is fixed so as to cover the entire outer surface 12ea on the other axial side (vehicle body side) of the bent portion 12e and the inner diameter end 12eb of the bent portion 12e. The body portion 15 is formed to extend further from the outer surface 12ea toward the constant velocity joint 8 and is formed in a substantially rectangular shape in cross-section. In the illustrated example, the body portion 15 is formed in a rectangular shape that is long in the axial direction in cross-section. The inner diameter corner portion 15b on the other axial side of the main body portion 15 is formed to be slightly inward in diameter or at approximately the same position as the inner diameter end portion 12eb of the bent portion 12e.

[0020] A triangular ridge 17 is integrally provided on the inner diameter side of the main body 15 when viewed in cross-section. This ridge 17 is formed in a continuous annular shape along the circumferential direction of the main body 15, and the triangular inner diameter tip (apex) is the elastic contact portion 13. The elastic contact portion 13 is provided on the ridge 17 that protrudes from the main body 15 toward the outer peripheral surface 8a, and the elastic contact portion 13 is provided in a position that does not overlap radially with the bent portion 12e. Specifically, the elastic contact portion 13 is provided on the other side (vehicle side) of the axial center of the main body 15. The surface of the ridge 17 on one side (wheel side) of the elastic contact portion 13 has an inclined portion 18 that slopes toward the outer diameter side from the elastic contact portion 13, and the surface of the ridge 17 on the other side of the elastic contact portion 13 has a tapered portion 16 that slopes toward the elastic contact portion 13 from the corner portion 15b of the main body 15.

[0021] The sealing member 10 will be further explained with reference to Figures 2 and 3. Figure 2(a) shows the process of assembling the constant velocity joint 8 to the bearing unit 1, and Figure 2(b) shows the state in which the bearing unit 1 and the constant velocity joint 8 are connected and the assembly is completed (enlarged view of part X in Figure 1). Figure 3 shows the state in which the constant velocity joint 8 is slightly eccentric in the bearing unit 1 (the axis of the bearing unit 1 is indicated by L, and the axis of the constant velocity joint 8 is indicated by L1). Note that the dashed line showing the sealing portion 14 in Figure 2(b) shows the state before the constant velocity joint 8 is assembled.

[0022] As shown in Figure 2(a), the sealing member 10 is attached to the inner ring member 4 by fitting its core cylindrical portion 12a onto the first outer peripheral surface 4b of the inner ring member 4. In this state, the constant velocity joint 8 is assembled toward the hub wheel 3 from the other axial side. At this time, if the sealing portion 14 is a lip portion (102) as shown in the comparative example, sealing member 100, in Figure 7, the lip portion will elastically deform from the other axial side to the one side. Therefore, in this case, the deformation direction of the lip portion is not opposed to the inflow direction of dust etc. flowing in from the other side, making it vulnerable to dust attack. According to the sealing member 10 of this embodiment, the sealing portion 14 can be made less prone to elastic deformation in the direction in which the constant velocity joint 8 is assembled (from the other side to the one side). In addition, the sealing portion 14 is configured with a tapered portion 16 that slopes from the inner diameter side corner portion 15b of the main body portion 15 toward the elastic contact portion 13, so that the sealing portion 14 does not reverse when the constant velocity joint 8 is assembled. In other words, as is clear from comparing the shape of the seal portion 14 shown in Figure 2(a) with the shape of the seal portion 14 shown in Figure 2(b), when the elastic contact portion 13 makes elastic contact with the outer peripheral surface 8a of the constant velocity joint 8, the outer diameter corner portion 15a of the main body portion 15 of the seal portion 14 is displaced outward from the extended end portion 12d, but the shape of the seal portion 14 itself does not deform significantly. Therefore, the seal portion 14 can be positioned facing the direction of inflow of dust, etc., flowing in from the other side, and a seal that is resistant to attacks from dust, muddy water, etc. can be constructed. Furthermore, the radial dimension of the seal portion 14 is formed to be larger than the radial dimension of the bent portion 12e, and the elastic contact portion 13 is provided further inward from the inner diameter end portion 12eb of the bent portion 12e, so a seal portion 14 with high reaction force and surface pressure can be constructed. Furthermore, as is clear from comparing the seal portion 14 shown by the dashed line and the seal portion 14 shown by the solid line in Figure 2(b), the amount of movement of the elastic contact portion 13 before and after assembly of the constant velocity joint 8 can be suppressed. Therefore, the seal member 10 can be applied to a bearing unit 1 equipped with a constant velocity joint 8 in which the area of ​​the outer peripheral surface 8a that the elastic contact portion 13 contacts is narrow.

[0023] Figure 3 shows the case where the constant velocity joint 8 is eccentric upward (radially). As shown in the enlarged view of section Y in Figure 3, as the outer peripheral surface 8a of the constant velocity joint 8 tilts outward in the radial direction, when the elastic contact portion 13 of the seal portion 14 elastically contacts the outer peripheral surface 8a, the position of the outer diameter side corner portion 15a of the main body portion 15 is displaced upward (towards the outer diameter) more than the position of the elastic contact portion 13 of the seal portion 14 shown in the enlarged view of section Z in Figure 3. However, in this case, since the bent portion 12e of the core body 11 and the elastic contact portion 13 of the seal portion 14 do not overlap radially, the seal member 10 maintains its shape even when the tightening allowance of the elastic contact portion 13 of the seal portion 14 increases without being constrained by the core body 11, while the position of the outer diameter side corner portion 15a of the main body portion 15 is displaced upward (towards the outer diameter). Therefore, even if eccentricity occurs in the constant velocity joint 8, the reaction force acting on the elastic contact portion 13 of the seal portion 14 is easily maintained, without impairing the sealing performance, and the joint can follow the eccentricity while maintaining its sealing properties.

[0024] Next, a modified example of the sealing member according to the above embodiment will be described with reference to Figures 4 to 6. Note that only the differences from the above embodiment will be described, and explanations of common effects and features will be omitted or simplified.

[0025] The sealing members 10A and 10B shown in Figures 4(a) and 4(b) are examples in which the bending angle of the bent portion 12e of the core body 11 differs from that of the above embodiment. In the above embodiment, the sealing member 10 is formed by bending it to approximately 90 degrees, and the length of the bent portion 12e is approximately the same as the radial dimension of the main body portion 15 of the sealing portion 14. However, this bending angle and the length of the bent portion 12e are not particularly limited. For example, as shown in Figure 4(a), the bent portion 12e may be slightly bent, and the length of the bent portion 12e may also be small. Also, as shown in Figure 4(b), the bending angle of the bent portion 12e may be approximately 120 degrees, and the length of the bent portion 12e may be approximately half the length of the main body portion 15 of the sealing portion 14.

[0026] The sealing members 10C and 10D shown in Figures 5(a) and 5(b) are examples in which the bending angle of the bent portion 12e of the core body 11 is the same as in the above embodiment, but the configuration of the sealing portion 14 differs from the above embodiment. In the sealing member 10C shown in Figure 5(a), the sealing portion 14 is similar in that the elastic contact portion 13 is provided further inward than the inner diameter end 12eb of the bent portion 12e, but it differs from the above embodiment in that multiple elastic contact portions 13 are provided. The radial dimension of the sealing portion 14 is larger than the radial dimension of the bent portion 12e, but it is not the dimension that covers the extended end 12d as in the above embodiment. Specifically, the main body portion 15 of the sealing portion 14 is fixed so as to cover the inner diameter end 12eb of the bent portion 12e, as well as the outer surface 12ea on the other axial side (vehicle body side) of the bent portion 12e. The main body portion 15 is formed extending further from the outer surface 12ea toward the constant velocity joint 8, and is formed in a substantially rectangular shape in cross-section, and is formed in a rectangular shape that is elongated in the axial direction in cross-section. The inner diameter corner portion 15b on the other axial side of the main body portion 15 is formed to be slightly inward in diameter or at approximately the same position as the inner diameter end portion 12eb of the bent portion 12e.

[0027] Multiple triangular ridges 17, 17 are integrally provided on the inner diameter side of the main body portion 15 when viewed in cross-section. These ridges 17 are formed in a continuous annular shape along the circumferential direction of the main body portion 15, and the triangular inner diameter side tips (tops) are elastic contact portions 13. The elastic contact portions 13 are provided on the ridges 17 that protrude from the main body portion 15 toward the outer peripheral surface 8a, and the elastic contact portions 13 are provided in a position that does not overlap radially with the bent portion 12e. Specifically, multiple elastic contact portions 13 are provided in parallel on one side (wheel side) and the other side (vehicle body side) of the axial center of the main body portion 15, and the seal member 10C in the illustrated example has two ridges 17, 17 and two elastic contact portions 13, 13. Of the two protruding portions 17, 17, on one side (wheel side) of the protruding portion 17, the surface on one side (wheel side) of the elastic contact portion 13 has an inclined portion 18 that slopes to one side in the axial direction as it moves from the elastic contact portion 13 toward the outer diameter, and the surface on the other side of the elastic contact portion 13 has a tapered portion 16 that slopes to the other side in the axial direction as it moves from the elastic contact portion 13 toward the outer diameter. Of the two protruding portions 17, 17, on the other side (vehicle body side) of the protruding portion 17, the surface on one side (wheel side) of the elastic contact portion 13 of the other side has an inclined portion 18 that slopes to one side in the axial direction as it moves from the elastic contact portion 13 toward the outer diameter, and the surface on the other side of the elastic contact portion 13 has a tapered portion 16 that slopes to the other side in the axial direction as it moves from the elastic contact portion 13 toward the outer diameter. According to the above configuration, by providing multiple elastic contact points 13, the number of contact points with the constant velocity joint 8 is increased, and the sealing performance of the sealing member 10C can be improved.

[0028] The sealing member 10D shown in Figure 5(b) differs in that it is equipped with a spring 50, and the shape of the main body 15 is not substantially rectangular, but has a locking portion 15c for locking the spring 50. In Figure 5(b), the boundary between the main body 15 and the protruding portion 17 is shown with a dashed line to make the configuration of the main body 15 and the protruding portion 17 easier to understand, but in reality they are formed integrally and the main body 15 and the protruding portion 17 are not separated into separate parts. The main body 15 of the sealing portion 14 is fixed so as to cover the outer surface 12ea of ​​the extended end 12d and the bent portion 12e, and the inner diameter end 12eb of the bent portion 12e. The main body 15 is formed extending further toward the constant velocity joint 8 from the outer surface 12ea, and a locking portion 15c is provided on its outer diameter side, which is recessed so as to lock the spring 50. The inner diameter corner portion 15b on the other axial side of the main body portion 15 is formed to be slightly on the outer diameter side than the inner diameter end portion 12eb of the bent portion 12e.

[0029] The inner diameter side of the main body 15 has a triangular projection 17 integrally provided in cross-section. This projection 17 is formed in a continuous annular shape along the circumferential direction of the main body 15, and the tip (apex) of the triangular inner diameter side is the elastic contact portion 13. The elastic contact portion 13 is provided on the projection 17 that protrudes from the main body 15 toward the outer peripheral surface 8a, and the elastic contact portion 13 is provided in a position that does not overlap radially with the bent portion 12e. Specifically, the elastic contact portion 13 is provided on the other side (vehicle side) of the axial center of the main body 15. The surface of the projection 17 on one side (wheel side) of the elastic contact portion 13 has an inclined portion 18 that slopes toward the outer diameter side from the elastic contact portion 13, and the surface of the projection 17 on the other side of the elastic contact portion 13 has a tapered portion 16 that slopes toward the elastic contact portion 13 from the corner portion 15b of the main body 15. With the above configuration, the spring 50 ensures that the elastic contact portion 13 can reliably make elastic contact with the constant velocity joint 8. Therefore, it becomes easier to follow eccentricity and vibrations of the constant velocity joint 8, and the sealing performance of the sealing member 10D can be improved.

[0030] The sealing member 10E shown in Figure 6 differs from the above embodiment in that the core body 11 does not have a stepped portion 12b and an extended cylindrical portion 12c, and the core body 11 is fitted to the second outer peripheral surface 4d instead of the first outer peripheral surface 4b. The sealing member 10E also differs in that the outer peripheral surface 12aa of the core body cylindrical portion 12a is covered with an elastic portion 19. The configuration of the sealing device 20 is the same as in the above embodiment, but differs in that the inner diameter side cylindrical portion 21a of the slinger member 21 is fitted directly to the first outer peripheral surface 4b without going through the core body 11. The configuration of the sealing portion 14 is the same as the sealing portion 14 of the sealing member 10 shown in Figure 2, etc. The core body 11 in the illustrated example is formed by bending into a substantially Z shape in cross-sectional view. The core body 11 has a core body cylindrical portion 12a, a bent portion 12e, and a second bent portion 12f. The core cylindrical portion 12a is formed in a cylindrical shape extending in the axial direction and is fitted onto the second outer peripheral surface 4d of the inner ring member 4. The bent portion 12e is formed by bending inward from the extended end 12d of the core cylindrical portion on the constant velocity joint 8 side (vehicle body side), which extends to directly above the constant velocity joint 8 in the assembled state. The bent portion 12e is formed with radial dimensions such that it does not contact the constant velocity joint 8 when the core 11 is mounted on the inner ring member 4. The end of the core cylindrical portion 12a on the inner ring member 4 side is provided with a second bent portion 12f formed by bending along the end face 4c. The end 12fa of the second bent portion 12f is configured such that it does not protrude radially outward from the first outer peripheral surface 4b when mounted on the inner ring member 4. The elastic portion 19 is fixed so as to cover the entire outer peripheral surface 12aa of the core cylindrical portion 12a and the outer surface 12fb of the second bent portion 12f. The elastic portion 19 has a contact portion 19a that covers the end fa of the second bent portion 12f, and the contact portion 19a is formed to elastically contact the inner diameter end 22a (lower end surface) of the encoder 22. With the above configuration, the core body 11 can be reinforced by covering the core body cylindrical portion 12a and the second bent portion 12f with the elastic portion 19, and deformation of the sealing member 10E can be suppressed even if the constant velocity joint 8 etc. becomes eccentric. In addition, the contact portion 19a can prevent muddy water etc. from entering between the inner diameter side cylindrical portion 21a and the first outer peripheral surface 4b.

[0031] Next, with reference to Figure 7, a comparative test between the sealing member 10 according to the above embodiment (example) and the sealing member 100 according to the comparative example will be described. This comparative test supports the above-mentioned effects of the sealing member 10. Note that the configuration of the core body 11 is the same, so the same reference numerals are used and the explanation is omitted.

[0032] In the comparative test, two types of sealing members, the sealing member 100 shown in the upper part of the table in Figure 7 and the sealing member 10 shown in the lower part of the table in Figure 7, were used, and the reaction forces of the comparative example and the embodiment were compared by changing the interference fit (d1 to d3). In addition, since the contact width changes when the interference fit is changed, the contact width was also compared between the comparative example and the embodiment. The sealing member 100 used as the comparative example comprises a sealing portion 101 fixed to the bent portion 12e and a lip portion 102 formed to extend inward from the inner diameter end of the sealing portion 101. The lip portion 102 is formed in the shape of a tongue that inclins to one side as it extends inward. In its natural state before elastic deformation (shown by the dashed line in Figure 7), this lip portion 102 is formed to overlap radially with the bent portion 12e of the core body 11. When the seal member 100 according to the comparative example is attached to the inner ring (not shown in Figure 7), the lip portion 102 elastically deforms so that the inner diameter side tip bends to one side.

[0033] <Results> In the comparative test, as shown in the table in Figure 7, the example seal member 10 and the comparative example seal member 100 were compared when the clamping allowance was d1 < d2 < d3. When the clamping allowance was d1, the reaction force of the example was three times that of the comparative example. When the clamping allowance was d2, the reaction force of the example was 2.5 times that of the comparative example. When the clamping allowance was d3, the reaction force of the example was 1.5 times that of the comparative example. Thus, the comparative test confirmed that under the same conditions, the reaction force of the example was greater than that of the comparative example. Furthermore, when the contact widths W1 to W3 of the lip portion 102 and the elastic contact portion 13 were measured for clamping allowances d1 to d3, it was confirmed that the difference in contact width between the example and the comparative example increased as the clamping allowance increased.

[0034] <Discussion> From the above, it was found that the embodiment had a higher reaction force even with the same overlap as the comparative example. This result indicates that the embodiment has higher sealing performance than the comparative example. Furthermore, the fact that the sealing performance is high even when the overlap is large supports the idea that even if the overlap of the sealing portion 14 increases due to the eccentricity of the constant velocity joint 8 explained in Figure 7, the sealing member 10 of the embodiment can improve sealing performance.

[0035] As described above, the sealing members 10, 10A to 10E are not limited to the configurations shown and explained as embodiments and their modifications. For example, a configuration in which the core body 11 shown in Figure 6 does not have a stepped portion 12b, or a configuration with an elastic portion 19, may be applied to the examples in Figures 2 to 5. Also, as shown in Figure 5(b), the main body portion 15 of the sealing portion 14 may be formed in a shape other than a rectangle in cross-section. Furthermore, the main body portion 15 is not limited to a configuration in which it is fixed to the entire outer surface 12ea of ​​the bent portion 12e, but may be fixed to a part of the outer surface 12ea. Also, the sealing portion 14 is not limited to a configuration in which a tapered portion 16 is provided, but may be, for example, a configuration in which the elastic contact portion 13 protrudes as a ridge. Furthermore, the bearing unit 1 to which the sealing member 10 is applied is not limited to a configuration in which the hub ring 3 and the constant velocity joint 8 are connected by face splines 3g and 8b. For example, the sealing member 10 may be applied to a bearing unit 1 in which a drive shaft, spline-fitted coaxially to a hub wheel 3, is connected to a drive source (drive transmission unit) via a constant velocity joint 8.

[0036] 2 Outer ring (outer member) 3 Hub ring (inner member) 4 Inner ring member (inner member) 40 Outer surface 5 Inner ring (inner member) 8 Constant velocity joint 8a Outer surface 10, 10A to 10E Seal member 11 Core body 12a Core body cylindrical portion 12d Extended end portion 12e Bent portion 12ea Outer surface 12eb Inner diameter side end portion 14 Seal portion 15 Main body portion 15a Outer diameter side corner portion 15b Inner diameter side corner portion 16 Tapered portion 13 Elastic contact portion

Claims

A sealing member that seals the space between an inner member that rotates coaxially with respect to an outer member and a constant velocity joint connected to the inner member, The device comprises a core body having a cylindrical core portion provided on one axial side and fitted to the outer circumferential surface of the inner member, and a bent portion that bends toward the inner diameter from an extended end extending from the cylindrical core portion toward the constant velocity joint on the other axial side, and an elastic seal portion having an annular body portion and an elastic contact portion that elastically contacts the outer circumferential surface of the constant velocity joint, The main body is fixed to the outer surface on the other axial side of the bent portion and extends further from the outer surface toward the constant velocity joint, The sealing member is characterized in that the elastic contact portion protrudes from the main body portion toward the outer peripheral surface and is provided so as not to overlap radially with the bent portion. 　 In claim 1, The radial dimension of the seal portion is formed to be larger than the radial dimension of the bent portion. The sealing member is characterized in that the elastic contact portion is provided further inward than the inner diameter end of the bent portion. 　 In claim 1 or claim 2, The main body is formed in a rectangular shape in cross-section. The sealing member is characterized in that the corner portion on the outer diameter side is displaced toward the outer diameter side as the elastic contact portion of the constant velocity joint makes elastic contact with the outer circumferential surface. 　 In claim 3, A sealing member characterized by having a tapered portion that slopes from the inner diameter corner of the main body toward the elastic contact portion.

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