Sealing device and sealing structure

Abstract

To provide a sealing device which can inhibit entry of foreign objects such as mud water, and to provide a sealing structure.SOLUTION: A sealing device 10 seals an annular space S formed between an outer member 2 and an inner member 5 which rotate relative to each other and includes: a first member 11 attached to the outer member; and a second member 24 attached to the inner member. The second member has an inner slinger member 25 and an outer slinger member 31. The inner slinger member includes: an inner cylindrical part 26 configured to be fitted in an outer peripheral surface of the inner member; and an outer cylindrical part 29 provided at the outer diameter side relative to the inner cylindrical part. The outer slinger member includes: a fitting cylindrical part 32 fitted in an outer peripheral surface of the outer cylindrical part; and a first circular-ring part 33 which is formed extending from one end of the fitting cylindrical part in a radial direction and forms a first labyrinth seal R1 with the first member.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a sealing device and a sealing structure.

Background Art

[0002] Conventionally, a sealing device for suppressing the intrusion of foreign matters such as muddy water into an annular space formed by an outer member and an inner member has been known. For example, Patent Document 1 below discloses a seal including an outer case fitted to the outer race of a bearing and a carrier having an inner axial wall fitted to the thrust rib of the inner race of the bearing. The carrier of this seal includes an outer radial wall that is continuous with the inner axial wall and extends outside the outer-facing surface of the outer race, and an inclined return wall that extends axially from this outer radial wall and surrounds the end of the outer race. It includes a plurality of radial walls extending in the radial direction and connection walls extending in the axial direction, and the cross-sectional shape is formed in a meandering shape.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the seal disclosed in Patent Document 1 above, the structure of the carrier that realizes the fluid barrier by the outer case fitted to the outer race of the bearing tends to be complicated, and further improvement is desired.

[0005] The present invention has been made in view of the above circumstances, and an object thereof is to provide a sealing device and a sealing structure capable of suppressing the intrusion of foreign matters such as muddy water.

Means for Solving the Problems

[0006] In order to achieve the above object, Configuration 1 of the sealing device of the present invention is a sealing device that seals an annular space formed between a relatively rotating outer member and an inner member, and includes a first member attached to the outer member and a second member attached to the inner member. The second member has an inner slinger member and an outer slinger member, the inner slinger member includes an inner cylindrical portion fitted to the outer peripheral surface of the inner member and an outer cylindrical portion provided on the outer diameter side of the inner cylindrical portion, and the outer slinger member includes a fitting cylindrical portion fitted to the outer peripheral surface of the outer cylindrical portion and a first annular portion formed to extend radially from one end portion of the fitting cylindrical portion and constituting a first labyrinth seal with the first member.

[0007] The following description of the embodiments discloses that the sealing device according to the present invention may have the following dependent configurations. <Configuration 2> In Configuration 1, the fitting cylindrical portion may constitute a second labyrinth seal with a peripheral member provided around the sealing device. <Configuration 3> In Configuration 1, the outer slinger member has a first annular portion formed to extend from the fitting cylindrical portion toward the outer diameter side and a second annular portion formed to extend toward the inner diameter side, and the second annular portion may constitute a second labyrinth seal with a peripheral member provided around the sealing device. <Configuration 4> In any one of Configurations 1 to 3, with the inner slinger member and the outer slinger member attached to the inner member, the end portion on the external space side in the axial direction of the fitting cylindrical portion may protrude to the external space side more than the outer cylindrical portion. <Configuration 5> In any one of Configurations 1 to 4, the inner slinger member may include a magnetic body that constitutes a magnetic encoder. <Configuration 6> In any one of Configuration 1 to Configuration 5, the first member may be provided on the inner diameter side of the first labyrinth seal and may be provided with a seal lip formed to extend so that the tip thereof is close to or in sliding contact with the second member.

[0008] In order to achieve the above object, a sealing structure of the present invention is a sealing structure for sealing an annular space formed between a relatively rotating outer member and an inner member by a sealing device, the sealing device including a first member attached to the outer member and a second member attached to the inner member, the second member having an inner slinger member and an outer slinger member, the inner slinger member including an inner cylindrical portion fitted to the outer peripheral surface of the inner member and an outer cylindrical portion provided on the outer diameter side of the inner cylindrical portion, the outer slinger member including a fitting cylindrical portion fitted to the outer peripheral surface of the outer cylindrical portion and a first annular portion formed to extend in the radial direction from one end portion of the fitting cylindrical portion and constituting a first labyrinth seal with the first member, and constituting a second labyrinth seal with a peripheral member provided around the sealing device.

Advantages of the Invention

[0009] Since the sealing device and the sealing structure of the present invention are configured as described above, it is possible to suppress the intrusion of foreign matters such as muddy water.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Mode for Carrying Out the Invention

[0011] Hereinafter, an example of a sealing device and a sealing structure of an embodiment will be described with reference to the drawings. In some of the drawings, some of the detailed reference numerals attached to other drawings are omitted. Also, in each drawing, the two-dot chain line of the seal portion indicates the shape before elastic deformation. FIG. 1 and FIG. 2 are views showing an example of a sealing device and a sealing structure according to the first embodiment and an example of a bearing device to which the sealing device is attached.

[0012] As shown in FIG. 2, the sealing device 10 according to the first embodiment seals an annular space S formed between a relatively rotating outer member 2 and an inner member 5. The sealing device 10 includes a first member 11 attached to the outer member 2 and a second member 24 attached to the inner member 5. The second member 24 has an inner slinger member 25 and an outer slinger member 31. With such a configuration, since the second member 24 is composed of two members, an inner slinger member 25 and an outer slinger member 31, each member can realize a shape that is difficult to configure with only one member while having a simple configuration. The inner slinger member 25 includes an inner cylindrical portion 26 fitted to the outer peripheral surface of the inner member 5 and an outer cylindrical portion 29 provided on the outer diameter side of the inner cylindrical portion 26. The outer slinger member 31 includes a fitting cylindrical portion 32 fitted to the outer peripheral surface of the outer cylindrical portion 29 and a first ring portion 33 formed to extend radially from one end portion of the fitting cylindrical portion 32 and constituting a first labyrinth seal R1 with the first member 11. With such a configuration, the intrusion of foreign matters such as muddy water can be suppressed by the first labyrinth seal R1. Further, since the outer slinger member 31 is fitted to the outer cylindrical portion 29 of the inner slinger member 25, displacement of the inner slinger member 25 fitted to the inner member 5 can be suppressed.

[0013] Further, as shown in FIG. 2, the sealing structure according to the first embodiment is a structure in which an annular space S formed between the relatively rotating outer member 2 and inner member 5 is sealed by a sealing device 10. The sealing device 10 includes a first member 11 attached to the outer member 2 and a second member 24 attached to the inner member 5. The second member 24 has an inner slinger member 25 and an outer slinger member 31. The inner slinger member 25 includes an inner cylindrical portion 26 fitted to the outer peripheral surface of the inner member 5 and an outer cylindrical portion 29 provided on the outer diameter side of the inner cylindrical portion 26. The outer slinger member 31 includes a fitting cylindrical portion 32 fitted to the outer peripheral surface of the outer cylindrical portion 29 and a first annular portion 33 formed to extend radially from one end portion of the fitting cylindrical portion 32 and constituting a first labyrinth seal R1 with the first member 11, and constitutes a second labyrinth seal R2 with a peripheral member provided around the sealing device 10. With such a configuration, the same effects as those of the above-described sealing device 10 can be achieved. Further, the second labyrinth seal R2 can suppress the intrusion of foreign matters such as muddy water from entering between the outer slinger member 31 and the peripheral member. Hereinafter, an example of a specific configuration will be described.

[0014] FIG. 1 shows a bearing device 1 that rotatably supports a wheel (not shown) of a vehicle such as an automobile about an axis. The bearing device 1 generally includes an outer ring 2 corresponding to the above-described outer member 2, an inner ring 5 corresponding to the above-described inner member 5, 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 and integrated with the hub ring 3 on the vehicle body side. A drive shaft 7 is coaxially spline-fitted to the hub ring 3, and the drive shaft 7 is connected to a drive source (drive transmission section) not shown via a constant velocity joint 8. The drive shaft 7 is integrated with the hub ring 3 by a nut 9 to prevent it from falling off the hub ring 3. The inner ring 5 (hub ring 3 and inner ring member 4) is rotatable about the axis L with respect to the outer ring 2, and the outer ring 2 and the inner ring 5 constitute two relatively rotating members, forming an annular space S. In the annular space S, two rows of rolling elements 6... are rotatably interposed between the raceway ring 2a of the outer ring 2 and the raceway rings 3a, 4a of the hub ring 3 and the inner ring member 4 while being held by a retainer 6a. The hub ring 3 has a cylindrical hub ring body 3b and a hub flange 3d formed to extend outward in diameter via a rising base 3c from the hub ring body 3b, and a wheel is attached and fixed to the hub flange 3d by bolts and nuts not shown. Further, a stepped portion 3e recessed toward the wheel side is provided in the hub flange 3d at a midway portion in the radial direction of the vehicle body side surface. This stepped portion 3e is composed of a circumferential surface substantially parallel to the axial direction and a side wall surface extending outward in diameter from the end on the wheel side of this circumferential surface. Further, as shown in FIG. 2, a chamfered corner portion 3f is formed at the end on the vehicle body side of the circumferential surface of the stepped portion 3e.

[0015] At both axial ends along the axial direction of the annular space S, between the outer ring 2 and the inner ring member 4 and between the outer ring 2 and the hub ring 3, sealing devices 10, 40 described later are mounted to seal both axial ends along the axial direction of the annular space S. This suppresses the intrusion of foreign matter such as mud and water into the annular space S and the leakage of the lubricant (such as grease) filled in the annular space S to the outside.

[0016] Next, an example of the specific configuration of the sealing device 10 according to the first embodiment mounted at the wheel-side end of the annular space S will be described. The first member 11 includes a core body 12 and a seal portion 17. The core body 12 is formed by pressing a steel plate such as SPCC or SUS. The core body 12 includes a first core body cylindrical portion 13 that is fitted to the inner peripheral surface of the outer ring 2. The core body 12 includes a first core body circular ring portion 14 that extends inward from the end of the first core body cylindrical portion 13 on the vehicle body side. The core body 12 includes a second core body circular ring portion 15 that extends outward from the end of the first core body cylindrical portion 13 on the wheel side and is provided to cover the end face of the outer ring 2 on the wheel side. The core body 12 includes a second core body cylindrical portion 16 that extends axially toward the vehicle body side from the outer diameter side end of the second core body circular ring portion 15.

[0017] The seal portion 17 is made of an elastic body such as a rubber material and is integrally formed by vulcanizing and adhering to the core body 12. The seal portion 17 is fixed so as to cover the entire surface of the core body 12 on the wheel side (outer space side). Further, the seal portion 17 wraps around the inner diameter side end of the first core body circular ring portion 14 and covers a part of the inner diameter side of the vehicle body side surface of the first core body circular ring portion 14, and wraps around the end of the second core body cylindrical portion 16 on the vehicle body side and covers the inner peripheral surface of the second core body cylindrical portion 16. With such a configuration, it is possible to prevent the seal portion 17 from being peeled off from the core body 12. Further, an annular protrusion 21 is formed on the seal portion 17, which is provided on the inner peripheral side of the second core body cylindrical portion 16, protrudes inward, and elastically contacts the outer peripheral surface of the outer ring 2. By mounting the first member 11 on the outer ring 2 with the annular protrusion 21 elastically contacting the outer peripheral surface of the outer ring 2, it is possible to prevent foreign matter such as mud and water from entering the fitting portion between the outer peripheral surface of the outer ring 2 and the first member 11.

[0018] On the inner diameter side of the first labyrinth seal R1 in the first member 11, a seal lip is provided which extends so that its tip is in sliding contact with the second member 24. With such a configuration, even if foreign matter such as muddy water enters the sealing device 10, further entry can be suppressed by the seal lip. In the present embodiment, one axial lip 18 and one grease lip 19, which are seal lips, are provided respectively. The axial lip 18 is formed to extend from the base of the seal portion 17 toward the wheel side in the axial direction, and has a shape that is inclined toward the outer diameter side as it extends toward the wheel side in the axial direction. In the illustrated example, the axial lip 18 is in elastic contact with an inner ring portion 28 of the inner slinger member 25, which will be described later.

[0019] The grease lip 19 is provided on the inner diameter side of the first core ring portion 14, is formed to extend from the base of the seal portion 17 toward the inner diameter side, and is inclined toward the vehicle body side in the axial direction as it goes toward the inner diameter side. The grease lip 19 is provided on the inner diameter side of the axial lip 18 and is in elastic contact with the inner cylindrical portion 26 of the inner slinger member 25. With such a configuration, the grease lip 19 can suppress the grease in the annular space S from entering the sealing device 10.

[0020] The seal portion 17 includes a weir portion 20 provided on the outer diameter side of the second core cylindrical portion 16. The weir portion 20 has a substantially rectangular shape in a radial cross-sectional view, and the wheel side surface faces the first ring portion 33 of the outer slinger member 31 in the axial direction with a gap therebetween to form the first labyrinth seal R1. By providing the weir portion 20 in a state of protruding to the outer diameter side of the outer peripheral surface of the outer ring 2, foreign matter such as muddy water flowing along the outer peripheral surface of the outer ring 2 can be blocked to suppress entry into the sealing device 10. The wheel side surface of the weir portion 20 is provided to be flush with the wheel side surface of the portion covering the wheel side of the second core ring portion 15 in the seal portion 17.

[0021] The second member 24 includes an inner slinger member 25 and an outer slinger member 31 formed by pressing a steel plate such as SPCC or SUS. The inner slinger member 25 includes an inner cylindrical portion 26 that fits onto the hub ring 3. The inner slinger member 25 includes a bent portion 27 that slopes outward in diameter as it extends axially toward the wheel side from the end of the inner cylindrical portion 26 on the wheel side in the axial direction. The inner slinger member 25 includes an inner ring portion 28 that extends outward in diameter from the end of the bent portion 27 on the outer diameter side and is provided along the side wall surface of the hub flange 3d. The inner slinger member 25 includes an outer cylindrical portion 29 that extends toward the vehicle body side from the end of the inner ring portion 28 on the outer diameter side. This outer cylindrical portion 29 is provided so as to overlap axially with the corner portion 3f that is the chamfered portion of the stepped portion 3e of the hub flange 3d when the inner slinger member 25 is mounted on the inner ring 5.

[0022] The outer slinger member 31 includes a fitting cylindrical portion 32 that fits onto the outer peripheral surface of the outer cylindrical portion 29 of the inner slinger member 25, and a first ring portion 33 that extends outward in diameter from the end of the fitting cylindrical portion 32 on the vehicle body side in the axial direction. The fitting cylindrical portion 32 is formed to have a larger axial dimension than the outer cylindrical portion 29 and fits onto substantially the entire outer peripheral surface of the outer cylindrical portion 29. The fitting cylindrical portion 32 is provided such that, when the inner slinger member 25 and the outer slinger member 31 are mounted on the inner ring 5, the end on the external space side (the wheel side in the axial direction in FIG. 2) in the axial direction projects to the external space side more than the outer cylindrical portion 29. With such a configuration, since the end of the fitting cylindrical portion 32 on the wheel side in the axial direction projects to the external space side more than the outer cylindrical portion 29, it is possible to reduce the possibility that foreign matter such as mud and water directly adheres to the inner slinger member 25 due to the fitting cylindrical portion 32.

[0023] This fitting cylindrical portion 32 forms a second labyrinth seal R2 with a peripheral member provided around the sealing device 10. With such a configuration, it is possible to suppress the intrusion of foreign matters such as muddy water toward the space between the fitting cylindrical portion 32 and the peripheral member. In the illustrated example, with the inner slinger member 25 and the outer slinger member 31 mounted on the hub ring 3, the fitting cylindrical portion 32 forms the second labyrinth seal R2 between the axially wheel-side end portion and the chamfered corner portion 3f provided at an intermediate portion in the radial direction of the hub flange 3d. With such a configuration, it is possible to suppress the intrusion of foreign matters such as muddy water toward the space between the hub flange 3d and the inner slinger member 25. In the illustrated example, an example in which the wheel-side end portion of the fitting cylindrical portion 32 is brought close to the corner portion 3f is shown. The gap between the wheel-side end portion of the fitting cylindrical portion 32 forming the second labyrinth seal R2 and the corner portion 3f may be set to an appropriate dimension so as to suppress the intrusion of foreign matters.

[0024] The first annular portion 33 that forms the first labyrinth seal R1 with the weir portion 20 is provided so as to face the first member 11 in the axial direction. The gap between the first annular portion 33 forming the first labyrinth seal R1 and the first member 11 may be set to an appropriate dimension so as to suppress the intrusion of foreign matters. This first annular portion 33 is formed so as to protrude to the outer diameter side from the first member 11 (the weir portion 20 of the seal portion 17). With such a configuration, since the first annular portion 33 is provided so as to cover the outer space side (wheel side) of the weir portion 20 via the axial gap, it is possible to suppress foreign matters such as muddy water scattered from the outside from directly adhering to the weir portion 20, and to suppress the intrusion of foreign matters into the first labyrinth seal R1. In the illustrated example, the first annular portion 33 includes the weir portion 20 of the seal portion 17 of the first member 11, and is provided so as to face in the axial direction the portion covering the outer diameter side portion of the second core annular portion 15 in the seal portion 17.

[0025] As described above, the second member 24 shown in FIG. 2 is composed of two members, an inner slinger member 25 and an outer slinger member 31. While forming the first labyrinth seal R1 with the first member 11, it is possible to form a second labyrinth seal R2 with a peripheral member provided around the sealing device 10.

[0026] Next, the sealing device 10A according to the second embodiment will be described with reference to FIG. 3. Note that the description will mainly focus on the configurations different from those of the sealing device 10 according to the first embodiment described above, and the description of the common configurations and effects will be omitted as appropriate. The sealing device 10A according to the present embodiment is a sealing device mounted on the wheel side end of the annular space S, as described above. This sealing device 10A is mainly different from the sealing device 10 according to the first embodiment described above in the configuration of the seal portion 17A of the first member 11A and the inner slinger member 25A and the outer slinger member 31A of the second member 24A.

[0027] The seal portion 17A is configured substantially the same as that of the first embodiment in terms of the axial lip 18A, the grease lip 19A, and the annular protrusion 21A. The seal portion 17A includes a wheel side protrusion 34 that protrudes axially toward the wheel side from the outer diameter side end of the weir portion 20A. The seal portion 17A includes an inner diameter side protrusion 36 that protrudes inward in diameter from the wheel side end of the wheel side protrusion 34, and a step portion 35 that protrudes outward in diameter from the wheel side end of the wheel side protrusion 34 and extends toward the wheel side from this protruding portion and is radially opposed to the first ring portion 33A of the outer slinger member 31A.

[0028] The inner slinger member 25A includes a curved portion 27A that is recessed and curved outward in diameter as it extends axially toward the wheel side from the axial wheel side end of the inner cylindrical portion 26A. The inner slinger member 25A includes an inner ring portion 28A that extends outward in diameter from the outer diameter side end of the curved portion 27A, and an outer cylindrical portion 29A that extends toward the vehicle body side from the outer diameter side end of the inner ring portion 28A. The inner slinger member 25A includes an outer ring portion 30 that extends outward in diameter from the axial vehicle body side end of the outer cylindrical portion 29A. The outer slinger member 31A is different from the first embodiment in that the first ring portion 33A is formed so as to extend outward in diameter from the end of the fitting cylindrical portion 32A on the wheel side in the axial direction. The fitting cylindrical portion 32A is fitted to the outer peripheral surface of the outer cylindrical portion 29A in a state of being in contact with the wheel side surface of the outer ring portion 30 of the inner slinger member 25A. The outer ring portion 30 of the inner slinger member 25A is provided so as to project to the outside in diameter from the outer peripheral surface of the fitting cylindrical portion 32A, and the outer ring portion 30, the first ring portion 33A, and the fitting cylindrical portion 32A define a concave groove for receiving the inner diameter side end portion of the inner diameter side projecting portion 36 of the seal portion 17A.

[0029] The first labyrinth seal R1 is configured in a bent shape with the second member 24A and the seal portion 17A facing each other with a gap therebetween. The first labyrinth seal R1 includes a gap between the outer diameter side end of the first ring portion 33A of the outer slinger member 31A and the inner peripheral surface of the stepped portion 35, a gap between the vehicle body side surface of the first ring portion 33A and the wheel side surface of the wheel side projecting portion 34, a gap between the outer peripheral surface of the fitting cylindrical portion 32A and the inner diameter side end portion of the inner diameter side projecting portion 36, and a gap between the outer ring portion 30 of the inner slinger member 25A and the vehicle body side surface of the inner diameter side projecting portion 36, which are communicated with each other. The sealing device 10A shown in FIG. 3 does not form a second labyrinth seal R2 with the peripheral member provided around it, but a complicated bent first labyrinth seal R1 is formed as compared with the first embodiment, and the intrusion of foreign matters such as muddy water into the sealing device 10A can be more effectively suppressed.

[0030] Next, a sealing device 40 according to the third embodiment mounted on the vehicle body side end of the annular space S will be described with reference to FIG. 4. The first member 41 includes a core body 42 and a seal portion 47 fixed to the core body 42. The core body 42 includes a first core body cylindrical portion 43 fitted to the inner peripheral surface of the outer ring 2. The core body 42 includes a first core body ring portion 44 extending inward in diameter from the end of the first core body cylindrical portion 43 on the wheel side, which is on the annular space S side. The core body 42 includes a second core body ring portion 45 extending outward in diameter from the end of the first core body cylindrical portion 43 on the vehicle body side and provided so as to cover the vehicle body side end surface of the outer ring 2. A concave portion 46 in which a part of the outer diameter side is recessed toward the vehicle body side is provided on the wheel side surface of the second core body ring portion 45.

[0031] The seal portion 47 is vulcanized and adhered to the core body 42 to be integrally formed. The seal portion 47 is fixed so as to cover the entire vehicle body side surface of the core body 42. The seal portion 47 wraps around the inner diameter side end of the first core body ring portion 44 and covers a part of the inner diameter side of the wheel side surface of the first core body ring portion 44, and wraps around the outer diameter side end of the second core body ring portion 45 and covers the recess 46 of the second core body ring portion 45, and is fixed. The seal portion 47 is provided with an annular protrusion 48 protruding toward the wheel side from the surface contacting the vehicle body side surface of the outer ring 2. When the first member 41 is mounted on the outer ring 2 in a state where the annular protrusion 48 is elastically in contact with the vehicle body side surface of the outer ring 2, it is possible to suppress foreign matters such as muddy water from entering the contact portion between the vehicle body side surface of the outer ring 2 and the first member 41.

[0032] On the inner diameter side of the first labyrinth seal R1 in the first member 41, a first axial lip 49 is provided which is formed to extend so that the tip is close to the second member 52. The first axial lip 49 is inclined toward the outer diameter side as it goes toward the vehicle body side, and further bends toward the outer diameter side so that the tip portion is substantially parallel to the radial direction. Even if foreign matters such as muddy water invade the sealing device 40, they are blocked by the tip portion of the first axial lip 49 bent toward the outer diameter side, and further invasion can be reduced. On the inner diameter side of the first axial lip 49, a second axial lip 50 is provided which protrudes toward the vehicle body side from the base portion of the seal portion 47, is inclined toward the outer diameter side as it goes toward the vehicle body side, and is close to the second member 52. On the inner diameter side of the second axial lip 50, a grease lip 51 is provided which is inclined toward the wheel side as it extends from the base portion of the seal portion 47 toward the inner diameter side.

[0033] The inner slinger member 53 of the second member 52 is provided with an inner cylindrical portion 54 that fits onto the outer peripheral surface of the inner ring member 4. A grease slip 51 is in sliding contact with this inner cylindrical portion 54. The inner slinger member 53 is provided with a bent portion 55 that slopes outward in diameter as it extends toward the vehicle body side in the axial direction from the end of the inner cylindrical portion 54 on the vehicle body side. The second axial lip 50 is close to the bent portion 55. The inner slinger member 53 is provided with an annular portion 56 that extends outward in diameter from the end of the bent portion 55 on the outer diameter side. This annular portion 56 is provided such that, when the sealing device 40 is mounted on the bearing device 1, the end on the outer diameter side is located on the inner diameter side of the inner peripheral surface of the outer ring 2. The inner slinger member 53 is provided with an outer cylindrical portion 57 that extends toward the wheel side from the end of the annular portion 56 on the outer diameter side. The outer cylindrical portion 57 is provided so as to be positioned between the first axial lip 49 of the first member 41 and the first core cylindrical portion 43, and is radially opposed to the seal portion 47 of the portion covering the inner peripheral surface of the first core cylindrical portion 43 with a gap therebetween. The end of the outer cylindrical portion 57 on the wheel side is axially opposed to the portion covering the first core annular portion 44 of the seal portion 47 with a gap therebetween. The tip of the first axial lip 49 faces the inner peripheral surface of the outer cylindrical portion 57 with a gap therebetween. Since the first axial lip 49 and the second axial lip 50 are close to the second member 52 (inner slinger member 53), it is possible to suppress the intrusion of foreign matter such as mud and water, and at the same time, reduce torque compared to a configuration in which a plurality of seal lips are in sliding contact. Further, since the grease slip 51 is in sliding contact with the inner cylindrical portion 54, it is possible to prevent grease or the like in the annular space S from entering the sealing device 40.

[0034] The inner slinger member 53 is provided with a magnetic body 58 that constitutes a magnetic encoder. The magnetic body 58 is fixed to the vehicle body side surfaces of the bent portion 55 and the annular portion 56 and is formed in an annular shape, with the N pole and the S pole magnetized alternately and continuously along the circumferential direction. By having the magnetic body 58 face a magnetic sensor G provided on the vehicle body or the like, a magnetic encoder for detecting the rotational speed of the inner ring 5 or the like can be constituted.

[0035] The outer slinger member 59 includes a fitting cylindrical portion 60 that fits onto the outer peripheral surface of the outer cylindrical portion 57 of the inner slinger member 53, and a first annular portion 61 that extends outward in the diameter direction from the wheel-side end of the fitting cylindrical portion 60. The first labyrinth seal R1 is configured such that the gap between the first annular portion 61 and the seal portion 47 facing in the axial direction, and the gap between the outer peripheral surface of the outer cylindrical portion 57 and the seal portion 47 facing the wheel-side end communicate with each other. As a result, the first labyrinth seal R1 is configured in a bent shape, and can effectively prevent foreign matter such as mud and water from entering the sealing device. The first annular portion 61 is provided so as to face a portion that extends outward in the diameter direction from the outer diameter-side end of the second core annular portion 45 in the seal portion 47 and a portion that covers the vehicle body side of the second core annular portion 45. In the illustrated example, the outer diameter-side end of the first annular portion 61 is formed so as to be located on the inner diameter side of the outer diameter-side end of the first member 41 (seal portion 47). However, similar to the first embodiment, it may be formed to protrude outward in the diameter direction from the first member 41 (seal portion 47).

[0036] The fitting cylindrical portion 60 is formed with a larger axial dimension than the outer cylindrical portion 57 and is fitted to a part of the outer peripheral surface of the outer cylindrical portion 57 on the vehicle body side. The fitting cylindrical portion 60 protrudes toward the vehicle body side from the outer cylindrical portion 57. With the inner slinger member 53 and the outer slinger member 59 attached to the inner ring member 4, a second labyrinth seal R2 is formed between the fitting cylindrical portion 60 and the constant velocity joint 8 which is a peripheral member. By forming the second labyrinth seal R2, the intrusion of foreign matters such as muddy water toward the gap between the fitting cylindrical portion 60 and the constant velocity joint 8 can be reduced, and the intrusion of foreign matters such as muddy water from the outside space side to the fitting portion between the inner cylindrical portion 54 and the inner ring member 4 can be reduced. In the illustrated example, the fitting cylindrical portion 60 is provided so as to overlap in the radial direction so as to cover the outer diameter side of the gap between the inner ring member 4 and the constant velocity joint 8 facing in the axial direction. The second labyrinth seal R2 is formed between the inner peripheral surface of the fitting cylindrical portion 60 and the outer peripheral surface of the constant velocity joint 8. By providing the fitting cylindrical portion 60 so as to cover the outer diameter side of the gap between the inner ring member 4 and the constant velocity joint 8, the fitting cylindrical portion 60 covers the end portion of the inner ring member 4 on the vehicle body side and the end portion of the constant velocity joint 8 on the wheel side like a shield, and the adhesion of foreign matters such as muddy water scattered from the outside can be reduced. Further, if the tip of the magnetic sensor G is provided between the fitting cylindrical portion 60 and the constant velocity joint 8, the adhesion of foreign matters such as muddy water scattered from the outside to the tip of the magnetic sensor G can be reduced.

[0037] Next, the sealing device 40A according to the fourth embodiment will be described with reference to FIG. 5. Note that the description will mainly focus on the configurations different from those of the sealing device 40 according to the third embodiment described above, and the description of the common configurations and effects will be omitted as appropriate. The sealing device 40A according to the present embodiment is a sealing device mounted on the vehicle body side end of the annular space S as described above. The configuration of the outer slinger member 59A of the second member 52A of this sealing device 40A is mainly different from that of the third embodiment described above. The fitting cylindrical portion 60A of the outer slinger member 59A is formed to have an axial dimension smaller than that of the outer cylindrical portion 57. The fitting cylindrical portion 60A is formed with a dimension such that, in a state where the inner slinger member 53 and the outer slinger member 59A are mounted on the inner ring 5, the end on the vehicle body side is positioned axially between the magnetic body 58 and the constant velocity joint 8, and is configured not to overlap the constant velocity joint 8 in the radial direction. The outer slinger member 59A is similar to the sealing device 40 shown in FIG. 4 in that it includes a first annular portion 61A extending outward in the radial direction from the end on the wheel side of the fitting cylindrical portion 60A.

[0038] The outer slinger member 59A has a second annular portion 62 formed to extend inward in the radial direction from the fitting cylindrical portion 60A. The second annular portion 62 constitutes a second labyrinth seal R2 with a peripheral member provided around the sealing device 40A. With such a configuration, the intrusion of foreign matter such as muddy water toward the space between the second annular portion 62 and the peripheral member can be reduced. In the illustrated example, the second annular portion 62 extends inward in the radial direction from the end on the vehicle body side of the fitting cylindrical portion 60A, and the end on the inner diameter side axially overlaps the bent portion 55 of the inner slinger member 53. The second annular portion 62 axially overlaps the constant velocity joint 8 in a state where the inner slinger member 53 and the outer slinger member 59A are mounted on the inner ring 5. The sealing device 40A constitutes a second labyrinth seal R2 with a long gap in the radial direction between it and the constant velocity joint 8 due to the axial overlap of the second annular portion 62 and the constant velocity joint 8. Further, the second annular portion 62 is provided so as to cover the magnetic body 58 provided on the inner slinger member 53 with a gap therebetween. With such a configuration, it is possible to suppress the adhesion of foreign matter such as muddy water to the magnetic body 58 covered by the second annular portion 62. Also, the magnetic sensor G is provided so as to face the magnetic body 58 through the second annular portion 62.

[0039] Next, the sealing device 40B according to the fifth embodiment will be described with reference to FIG. 6. Note that mainly the configurations different from the sealing device 40 according to the third embodiment described above will be described, and the description of the common configurations and effects will be omitted as appropriate. Similar to the above, the sealing device 40B according to the present embodiment is a sealing device mounted on the end on the vehicle body side of the annular space S. The first member 41A includes a core 42A that is generally the same as described above. The seal portion 47A fixed to this core 42A includes an axial lip 49A that inclines toward the outer diameter side as it extends toward the vehicle body side, instead of the first axial lip 49 and the second axial lip 50 described above, and that is in sliding contact with the second member 52B. This axial lip 49A is in sliding contact with the annular portion 56A of the inner slinger member 53A. Even if foreign matter such as mud and water enters the sealing device 40B, it is possible to suppress the entry of further foreign matter and prevent it from reaching the sliding contact portion between the grease lip 51A and the inner cylindrical portion 54A. In the core 42A, the middle portion in the radial direction of the first core annular portion 44A is bent toward the vehicle body side more than the sealing device 40 shown in FIG. 4, and the inner diameter side portion is provided on the vehicle body side more than the sealing device 40 shown in FIG. 4. The axial lip 49A is formed to protrude from the seal portion 47A that covers the inner diameter side portion of the first core annular portion 44A. Note that the configurations of the first core cylindrical portion 43A, the second core annular portion 45A, and the recess 46A of the core 42A are substantially the same as those of the sealing device 40 shown in FIG. 4.

[0040] The inner slinger member 53A of the second member 52B has configurations of the inner cylindrical portion 54A and the bent portion 55A that are substantially the same as those of the sealing device 40 shown in FIG. 4. The annular portion 56A of the inner slinger member 53A is different from the sealing device 40 shown in FIG. 4 in that, when the inner slinger member 53A is mounted on the inner ring member 4, the outer diameter side end portion is positioned on the outer diameter side more than the inner peripheral surface of the outer ring 2 and axially overlaps with the end surface on the vehicle body side of the outer ring 2. Further, the outer cylindrical portion 57A of the inner slinger member 53A is provided at a position that axially overlaps with the second core annular portion 45A of the first member 41A. Further, the magnetic body 58A is provided on the vehicle body side surface of the annular portion 56A and does not cover the bent portion 55A, which is different from the configuration of FIG. 4.

[0041] With the inner slinger member 53A and the outer slinger member 59B attached to the inner ring member 4, the point that a second labyrinth seal R2 is formed between the fitting cylindrical portion 60B of the outer slinger member 59B and the outer peripheral surface of the constant velocity joint 8 which is a peripheral member is the same as that of the embodiment shown in FIG. 4. The outer slinger member 59B is different from the embodiment shown in FIG. 4 in that a first ring portion 61B is formed by extending radially inward from the wheel-side end of the fitting cylindrical portion 60B so as to pass between the second core cylindrical portion 45A of the first member 41A and the outer cylindrical portion 57A of the inner slinger member 53A. The first ring portion 61B is axially opposed to the portion covering the second core cylindrical portion 45A in the seal portion 47A with a gap therebetween. Further, the outer slinger member 59B includes a cylindrical portion 63 extending toward the wheel side from the inner diameter-side end of the first ring portion 61B. This cylindrical portion 63 is radially opposed to the portion covering the first core cylindrical portion 43A in the seal portion 47A with a gap therebetween. The first labyrinth seal R1 is formed by the first ring portion 61B and the cylindrical portion 63 of the outer slinger member 59B being opposed to the seal portion 47A with a gap therebetween, thereby forming the bent first labyrinth seal R1. In the embodiments of FIGS. 4 and 5, the inner slinger member and the outer slinger member are opposed to each other with a gap therebetween, thereby forming the bent first labyrinth seal R1. On the other hand, in the present embodiment, even if the inner slinger member 53A is not opposed to the seal portion 47A with a gap therebetween, the first ring portion 61B and the cylindrical portion 63 of the outer slinger member 59B are opposed to the seal portion 47A with a gap therebetween, so that the bent first labyrinth seal R1 can be formed.

[0042] The different configurations described in the above embodiments may be appropriately modified, recombined, and applied as necessary, or combined and applied. Further, each member is not limited to the configuration described above. For example, the outer slinger member may be configured to be provided with a cylindrical portion that covers the outer ring or the outer peripheral surface of the first member with a gap therebetween. Further, the inner slinger member may be configured not to be provided with a bent portion or a curved portion. In such a case, a ring portion extending radially outward from the end of the inner cylindrical portion may be provided.

Explanation of Reference Numerals

[0043] 1 Bearing device 2 Outer ring (outer member) 3 Hub ring (inner member) 4 Inner ring member (inner member) 5 Inner ring (inner member) 3D Hub flange (peripheral member) 8 Constant velocity joint (peripheral member) 10, 10A, 40, 40A, 40B Sealing device 11, 11A, 41, 41A First member 18, 18A, 49, 49A, 50 Axial lip (sealing lip) 19, 19A, 51, 51A Grease lip (sealing lip) 24, 24A, 52, 52A, 52B Second member 25, 25A, 53, 53A Inner slinger member 26, 26A, 54, 54A Inner cylindrical part 29, 29A, 57, 57A Outer cylindrical part 31, 31A, 59, 59A, 59B Outer slinger member 32, 32A, 60, 60A, 60B Fitting cylindrical part 33, 33A, 61, 61A, 61B First circular ring part 58, 58A Magnet 62 Second circular ring part R1 First labyrinth seal R2 Second labyrinth seal

Claims

1. A sealing device for sealing an annular space formed between a relatively rotating outer member and an inner member, comprising: a first member attached to the outer member and a second member attached to the inner member; the second member having an inner slinger member and an outer slinger member; the inner slinger member including an inner cylindrical portion fitted to the outer peripheral surface of the inner member and an outer cylindrical portion provided on the outer diameter side of the inner cylindrical portion; the outer slinger member including a fitting cylindrical portion fitted to the outer peripheral surface of the outer cylindrical portion and a first annular portion formed to extend radially from one end portion of the fitting cylindrical portion and constituting a first labyrinth seal with the first member.

2. In claim 1, the fitting cylindrical portion constitutes a second labyrinth seal with a peripheral member provided around the sealing device.

3. In claim 1, the outer slinger member has a first annular portion formed to extend outward in diameter from the fitting cylindrical portion and a second annular portion formed to extend inward in diameter; the second annular portion constitutes a second labyrinth seal with a peripheral member provided around the sealing device.

4. In any one of claims 1 to 3, in a state where the inner slinger member and the outer slinger member are attached to the inner member, an end portion of the fitting cylindrical portion on the external space side in the axial direction protrudes to the external space side more than the outer cylindrical portion.

5. In any one of claims 1 to 3, the inner slinger member includes a magnetic material constituting a magnetic encoder.

6. In any one of claims 1 to 3, on the inner diameter side of the first member relative to the first labyrinth seal, a seal lip is provided which extends such that its tip is close to or in sliding contact with the second member.

7. A sealing structure for sealing an annular space formed between a relatively rotating outer member and an inner member with a sealing device, comprising: the sealing device including a first member attached to the outer member and a second member attached to the inner member; the second member having an inner slinger member and an outer slinger member; The inner slinger member includes an inner cylindrical portion fitted to the outer peripheral surface of the inner member, and an outer cylindrical portion provided on the outer diameter side of the inner cylindrical portion. The outer slinger member includes a fitting cylindrical portion fitted to the outer peripheral surface of the outer cylindrical portion, and a first annular portion formed to extend radially from one end portion of the fitting cylindrical portion and constituting a first labyrinth seal with the first member. A second labyrinth seal is formed between the outer slinger member and a peripheral member provided around the sealing device.

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