Sealing device

Abstract

A hub seal (1) is provided with a seal body (3) and a slinger (4). The slinger (4) is provided with a flange section (31) and a cylindrical section (32). An outer cylinder surface (3a) is formed on the seal body (3). The labyrinth lip (40) extends toward the cylindrical section (32) of the slinger (4) on the outer peripheral side of the side lip (21). The cylindrical section (32) of the slinger (4) has a weir section (33). A first gap (S1) and a second gap (S2) are formed between the outer cylinder surface (3a) and the cylinder part (32). A third gap (S3) is formed between the weir portion (33) and a portion of the elastic body portion (20). A fourth gap (S4) is formed between the labyrinth lip (40) and the cylinder part (32). A space (S5) between the cylindrical section (32) and the side lip (21) communicates with the outside of the second gap (S2) via the fourth gap (S4), the third gap (S3), the first gap (S1), and the second gap (S2).

Description

Technical Field

[0001] This invention relates to a sealing device. Background Technology

[0003] In vehicles, such as automobiles, wheel hub bearings that rotatably support the wheels have traditionally been equipped with hub seals as sealing devices to achieve a seal in the gap formed between the outer and inner rings. Hub seals seal the lubricant inside the wheel hub bearing while preventing foreign matter from entering. Wheel hub bearings are exposed to harsh environments directly from rainwater, mud, dust, and other foreign matter; therefore, improved sealing performance against foreign matter is required for hub seals. Furthermore, based on requirements such as low fuel consumption, it is necessary to reduce the sliding resistance (torque resistance) exerted by the sealing lip on the wheel hub bearing for hub seals. While increasing the sealing lip is considered to improve the sealing performance of the hub seal, this increases the torque resistance. Therefore, a solution has been proposed that improves the sealing performance against foreign matter by using an oil slinger to form a labyrinth seal, without increasing the torque resistance of the hub seal (for example, see Invention Patent Document 1).

[0004] Existing technical documents Invention Patent Documents Invention Patent Document 1: Japanese Patent Application Publication No. 2010-91036 Summary of the Invention

[0005] The problem that the invention aims to solve As described above, since hub bearings are used in harsh environments where they are directly exposed to foreign matter such as rainwater, mud, and dust, even hub seals with labyrinth seals as disclosed in Patent Document 1 can still allow foreign matter to enter through the labyrinth seal. In particular, liquid foreign matter such as rainwater, mud, or rainwater or mud containing dust can enter through the labyrinth seal. Therefore, hub seals require further improvements in their sealing performance against liquid foreign matter. Thus, for sealing devices used in bearings such as hub bearings that involve the entry of liquid foreign matter and are used in harsh environments, a configuration that improves the sealing performance against liquid foreign matter is required.

[0006] The present invention was made in view of the above-mentioned problems, and its object is to provide a sealing device that can improve the sealing performance against liquid foreign matter.

[0007] Methods for solving problems To achieve the above objectives, the sealing device of the present invention is a sealing device that seals the gap between an outer peripheral component and an inner peripheral component that are rotatable relative to each other about their axes, wherein the inner peripheral component is at least partially surrounded by the outer peripheral component. The sealing device comprises: a sealing device body fixed to the outer peripheral component; and an oil-slinging ring fixed to the inner peripheral component. The sealing device body includes: an annular reinforcing ring surrounding the axis; and an annular... The oil-slinger ring comprises an elastomer portion formed of an elastomer, the elastomer portion being an annular portion extending radially around the axis; and a cylindrical portion extending along the axis in the axial direction from the outer peripheral end of the annular portion. An outer cylindrical surface is formed on the sealing device body, the outer cylindrical surface being an annular portion extending along the axis. The elastomer portion has a side lip and a labyrinth lip, and the cylindrical portion of the oil-slinger ring is located further than the labyrinth lip. At a position near the outer periphery, the side lip extends toward the other side in the axial direction and contacts the oil slinger ring. The labyrinth lip extends toward the cylindrical portion of the oil slinger ring further outward than the side lip. The cylindrical portion of the oil slinger ring has a weir at one end, the weir being an annular portion extending toward the outer periphery. The outer cylindrical surface of the sealing device body faces at least a portion of the end of the cylindrical portion of the oil slinger ring containing the weir from the outer periphery, forming a first gap between the end with the weir. Additionally, at the position of the cylindrical portion... A second gap is formed between the portion of the outer cylinder that is not the end of the weir facing the outer cylinder surface. The weir faces the portion of the elastic body from the other side, and a third gap is formed between the portion of the elastic body and the weir. A portion of the labyrinth lip faces the cylinder of the oil slinger from the inner circumferential side, and a fourth gap is formed between the labyrinth lip and the cylinder of the oil slinger. The space between the cylinder of the oil slinger and the side lip communicates with the outside of the second gap via the fourth gap, the third gap, the first gap, and the second gap.

[0008] In one aspect of the sealing device of the present invention, the radial width of the fourth gap is the width for forming a labyrinth seal against liquid foreign matter.

[0009] In one aspect of the sealing device, the labyrinth lip is inclined relative to the cylindrical portion of the oil-slinging ring in such a manner that the radial width of the fourth gap at the front end is minimized.

[0010] In a sealing device according to one aspect of the present invention, the radial width of the first gap is narrower than the radial width of the second gap.

[0011] In a sealing device according to one aspect of the present invention, the radial width of the first gap is the width that forms a labyrinth seal for liquid foreign matter, and the radial width of the second gap is the width that does not form a labyrinth seal for liquid foreign matter.

[0012] In one aspect of the sealing device of the present invention, foreign matter flowing into the second gap can be discharged from the second gap.

[0013] In a sealing device according to one aspect of the present invention, the weir portion has a weir surface, which is an annular surface extending from the end toward the inner circumferential side and facing the other side around the axis, and the cylindrical portion has an inner cylindrical surface, which is a cylindrical surface extending from the end of the weir surface on the inner circumferential side toward the other side and facing the outer circumferential side.

[0014] In one aspect of the sealing device of the invention, the end of the weir is an annular surface facing the outer peripheral side around the axis.

[0015] In a sealing device according to one aspect of the invention, the elastomeric portion has an intermediate lip extending toward the oil-slinging ring on a more inner circumferential side than the side lip.

[0016] In a sealing device according to one aspect of the invention, the elastomeric portion has a grease lip extending from a side further than the intermediate lip and contacting the oil-slinging ring.

[0017] In one aspect of the sealing device according to the present invention, the one side is the inner side, and the sealing device is the outer side sealing device.

[0018] In one aspect of the sealing device according to the present invention, the side is the outer side, and the sealing device is an inner side sealing device.

[0019] The effects of the invention The sealing device according to the present invention can improve the sealing performance against liquid foreign matter. Attached Figure Description

[0021] Figure 1 This is a cross-sectional view showing a hub bearing as an example, based on a plane including the axis.

[0022] Figure 2 yes Figure 1 The image shows a partially enlarged cross-sectional view near the hub seal according to the first embodiment of the present invention.

[0023] Figure 3 yes Figure 2 A partially enlarged cross-sectional view of the hub seal in the image.

[0024] Figure 4 yes Figure 2 A cross-sectional view of a modified example of a hub seal shown.

[0025] Figure 5 yes Figure 2 A partially enlarged cross-sectional view of another variation of the hub seal shown.

[0026] Figure 6 yes Figure 1 The image shows a partially enlarged cross-sectional view near the hub seal according to the second embodiment of the present invention.

[0027] Figure 7 yes Figure 6 A partially enlarged cross-sectional view of the hub seal in the image.

[0028] Figure 8 yes Figure 2 A cross-sectional view of a modified example of a hub seal shown.

[0029] Symbol Explanation 1, 2 Hub seal (sealing device), 3 Sealing body (sealing device body), 3a Outer cylinder surface, 4, 6 Oil slinger ring, 5 Sealing gasket, 10 Reinforcing ring, 11 Fitting part, 11a Outer peripheral surface, 12 Lip support part, 12a Return part, 12b Lip flange part, 13 Flange part, 20 Elastomer part, 21 Side lip, 22 Middle lip, 23 Grease lip, 24 Base part, 24a Outer peripheral facing part, 24b Facing part, 25 Ring protrusion part, 25a Inner end, 26, 27 Sealing gasket part, 31, 35 Flange part (circular part), 31a, 35a Contact surface, 31b Inner peripheral surface, 32 Cylinder part, 32a Inner cylinder peripheral surface, 33 Weir part, 33a End, 33b Weir surface, 33c Side side, 34 Fitting part, 34a Contact surface, 40 Labyrinth lip, 41 Front end, 100 Hub bearing, 100a Clearance, 101 Outer ring, 101a Inner opening, 101b Outer opening, 101c Inner circumferential surface, 101d Outer circumferential surface, 101e Inner end face, 101f Inner circumferential surface, 101g Outer circumferential surface, 101h Outer end face, 102 Inner ring, 103 Bearing ball, 104 Inner ring component, 104a Outer circumferential surface, 105 Hub ring, 105a Shaft part, 105b Wheel mounting flange, 105c Transition part, 105d Inner circumferential surface, 105e Outer circumferential surface, 105f Side surface, 106 Retainer, 107 Through hole, G Grease, L1, L2, L3 Length, S1, S4 Labyrinth gap (first gap), S2 discharge gap (second gap), S2a opening, S3 gap, x-axis, W1, W2, W3 widths. Detailed Implementation

[0031] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

[0032] The sealing device of this invention is a sealing device that seals the gap between an outer peripheral component and an inner peripheral component that are rotatable relative to each other with respect to their axes. The inner peripheral component is at least partially surrounded by the outer peripheral component. The sealing device of this invention is applicable, for example, to wheel hub bearings. Figure 1 This is a cross-sectional view showing a hub bearing 100 as an example, based on a plane including the axis. (See attached image.) Figure 1 As shown, the wheel hub bearing 100 is a conventionally known wheel hub bearing, installed in vehicles such as automobiles, and rotatably supports the wheel in the axle or suspension system. It should be noted that the sealing device involved in this invention is not limited to wheel hub seals, and its application is not limited to wheel hub bearings.

[0033] Specifically, such as Figure 1 As shown, the wheel hub bearing 100 includes: an annular outer ring 101, which is an outer peripheral component and has an axis x as its central axis or approximately its central axis; an inner ring 102, which is an inner peripheral component and has an axis x as its central axis or approximately its central axis, and is partially surrounded by the outer ring 101 and is capable of rotating relative to the outer ring 101; and a plurality of bearing balls (rolling elements) 103 disposed between the outer ring 101 and the inner ring 102. In the operating state of the wheel hub bearing 100 installed in a vehicle or the like, the outer ring 101 is fixed, and the inner ring 102 is capable of rotating relative to the outer ring 101. Specifically, the inner ring 102 has an inner ring component 104 and a hub ring 105, the hub ring 105 having a cylindrical or approximately cylindrical shaft portion 105a extending along the axis x and a wheel mounting flange 105b. The wheel mounting flange 105b is a disc-shaped portion extending from one end of the axle portion 105a toward the outer periphery. It is the portion for mounting a brake disc rotor (not shown) and a tire wheel via multiple hub bolts (not shown). The axle portion 105a and the wheel mounting flange 105b are smoothly connected on the inner periphery. The transition portion 105c, where the axle portion 105a and the wheel mounting flange 105b are connected on the inner periphery, has a profile with a smooth, arc-shaped or curved profile drawn on a cross-section based on a plane containing the axis x. The inner ring component 104 fits into the end of the axle portion 105a of the hub ring 105 to hold the bearing balls 103 within the gap 100a between the outer ring 101 and the inner ring 102. The bearing balls 103 are held by a retainer 106 within the gap 100a between the outer ring 101 and the inner ring 102.

[0034] The outer ring 101 has a through hole 107 extending in the x-axis direction. The shaft portion 105a of the inner ring 102's hub ring 105 is inserted into this through hole 107. An annular gap 100a extending along the x-axis is formed between the shaft portion 105a and the through hole 107. As described above, bearing balls 103 are accommodated and held by a retainer 106 within this gap 100a, and lubricant is applied or injected. A sealing device 1 is installed in the inner opening 101a of the outer ring 101, which forms an opening that opens the gap 100a between the inner ring component 104 and the shaft portion 105a and the through hole 107 from the inside. On the other hand, a sealing device 2 is installed in the outer opening 101b of the outer ring 101, which forms an opening that opens the gap 100a from the outside.

[0035] Sealing device 1 is the sealing device according to the first embodiment of the present invention, and is an internal hub seal. On the other hand, sealing device 2 is the sealing device according to the second embodiment of the present invention, and is an external hub seal. Through sealing devices 1 and 2, the gap 100a between the shaft portion 105a of the hub ring 105 and the inner ring component 104 and the outer ring 101 is sealed, preventing lubricant in the gap 100a from leaking to the outside, and preventing foreign matter such as rainwater, mud, and dust from entering the gap 100a from the outside. It should be noted that the configuration of the hub bearing to which sealing devices 1 and 2 are applied is not limited to the configuration of the hub bearing 100 described above. In the following description, the sealing device applied to the hub bearing will also be referred to as a hub seal.

[0036] Next, the hub seal 1 according to the first embodiment of the present invention will be described. Figure 2 yes Figure 1 A partially enlarged cross-sectional view near the hub seal 1 in the image. Figure 3 yes Figure 2 A partially enlarged cross-sectional view of the hub seal 1 in the image. Figure 2 The diagram shows one side of the hub seal 1 in its service state, based on a cross-section of a plane including the axis x. It should be noted that, in the service state, the sealing body 3 and the oil slinger ring 4 are mounted on the hub bearing 100 in a predetermined relative position.

[0037] like Figure 2 , 3As shown, the hub seal 1 includes: a sealing body 3 fixed to the outer ring 101 as the main body of the sealing device; and an oil slinger ring 4 fixed to the inner ring 102. The sealing body 3 includes: an annular reinforcing ring 10 surrounding the axis x; and an annular elastic body portion 20 formed of an elastic body mounted on the reinforcing ring 10 and surrounding the axis x. The oil slinger ring 4 includes: a flange portion 31 as an annular portion, which is an annular portion extending radially around the axis x; and a cylindrical portion 32, which is a cylindrical portion extending along the axis x from the outer peripheral end of the flange portion 31 in the direction of the axis x toward one side (outer side). An outer cylindrical surface 3a is formed on the sealing body 3, which is an annular cylindrical surface extending along the axis x. The elastic body portion 20 has a side lip 21 and a labyrinth lip 40. The cylindrical portion 32 of the oil slinger ring 4 is located further outward than the labyrinth lip 40. The side lip 21 extends toward the other side (inner side) in the x-axis direction and contacts the oil slinger ring 4. The labyrinth lip 40 extends toward the cylindrical portion 32 of the oil slinger ring 4 from a more peripheral side than the side lip 21. The cylindrical portion 32 of the oil slinger ring 4 has a weir portion 33 at its outer end, which is an annular portion extending toward the outer peripheral side. The outer cylindrical surface 3a of the sealing body 3 faces at least a portion of the end 33a of the cylindrical portion 32 of the oil slinger ring 4 that includes the weir portion 33 from the outer peripheral side, forming an annular first gap S1 between the sealing body 3 and the end 33a of the weir portion 33. In addition, an annular second gap S2 is formed between the sealing body 32 and the portion of the cylindrical portion 32 that does not face the end 33a of the weir portion 33. The weir portion 33 faces a portion of the elastomer portion 20 from the inner side, forming an annular third gap S3 between the sealing body 3 and the portion of the elastomer portion 20. A portion of the labyrinth lip 40 faces the cylindrical portion 32 of the oil slinger 4 from its inner circumferential side, forming an annular fourth gap S4 between it and the cylindrical portion 32 of the oil slinger 4. The space S5 between the cylindrical portion 32 of the oil slinger 4 and the side lip 21 communicates with the outer side of the second gap S2 via the fourth gap S4, the third gap S3, the first gap S1, and the second gap S2. The configuration of the hub seal 1 will be described in detail below.

[0038] It should be explained that, for example Figure 1 As shown, the outer side refers to the side in the direction of arrow a along the x-axis. On the other hand, as... Figure 1 As shown, the inner side refers to the side in the direction of arrow b along the x-axis. In the wheel hub bearing 100 mounted on a vehicle, the outer side is the wheel side, and the inner side is the chassis side. Furthermore, radial direction refers to the direction orthogonal to the x-axis. Additionally, the outer peripheral side refers to the side of the wheel hub bearing 100 that is radially away from the x-axis, such as... Figure 1 As shown, this is the side in the direction of arrow c. The inner circumferential side refers to the side of the hub bearing 100 that is radially closer to the axis x. Figure 1As shown, this is the side in the direction of arrow d. Furthermore, the axis x of the hub seal 1 mounted on the hub bearing 100 is aligned with or approximately aligned with the axis of the hub bearing 100. For ease of explanation, the axis of the hub bearing 100 is designated as axis x.

[0039] like Figure 2 As shown, the reinforcing ring 10 is, for example, a ring-shaped metal component with the axis x as its central axis or approximately its central axis, formed by being pressed into and fitted into the through hole 107 of the outer ring 101 of the hub bearing 100. By pressing the reinforcing ring 10 into the outer ring 101, the sealing body 3 is fixed to the outer ring 101. Figure 2 As shown, the reinforcing ring 10 has, for example, a cylindrical fitting portion 11; a lip support portion 12 that bends inward from the outer end of the fitting portion 11 and extends towards the inner periphery; and an annular plate-shaped flange portion 13 that extends outward from the inner end of the fitting portion 11.

[0040] The fitting part 11 is, for example, a cylindrical or approximately cylindrical part with the axis x as its central axis or approximately its central axis, such as... Figure 1 , 2 As shown, the outer peripheral surface 11a, which is the outer peripheral side, is pressed into the inner opening 101a of the outer ring 101 and fitted with its inner peripheral surface 101c. The lip support portion 12 is, for example, shaped to position the side lip 21, the intermediate lip 22 (described later), and the grease lip 23 in the hub seal 1 relative to the oil slinger ring 4 at a desired position. Figure 2 As shown, the lip support portion 12 has, for example, a return portion 12a and a lip flange portion 12b. The return portion 12a is, for example, a portion that bends inward from the outer end of the fitting portion 11. The lip flange portion 12b is, for example, an annular, plate-like portion extending inward from the inner end of the return portion 12a. Figure 2 As shown, the flange portion 13 is, for example, an annular, plate-like portion extending radially about or approximately centered on the axis x. The reinforcing ring 10 is, for example, a component formed integrally from a metal sheet by stamping or forging. The fitting portion 11, the lip support portion 12, and the flange portion 13 are integrally formed from the same material and are continuous. Examples of metal materials for the reinforcing ring 10 include stainless steel and SPCC (cold-rolled steel).

[0041] As described above, the elastomer portion 20 is mounted on the reinforcing ring 10, such as Figure 2 As shown, for example, it is integral with the reinforcing ring 10 by covering it from the inside. In addition to the side lip 21, the elastomer portion 20 also has, for example, a middle lip 22 and a grease lip 23. The side lip 21, the middle lip 22, and the grease lip 23 are annular sealing lips surrounding the axis x. Figure 2As shown, the middle lip 22 extends inward, for example, further inward than the side lip 21, and contacts the oil-slinging ring 4. Figure 2 As shown, the grease lip 23 extends outward from, for example, the middle lip 22 and contacts the oil slinger ring 4. The side lip 21 and the middle lip 22 contact the flange portion 31 of the oil slinger ring 4 to prevent foreign matter from entering the gap 100a of the hub bearing 100, and also to prevent lubricant from flowing out of the gap 100a. Furthermore, the grease lip 23 prevents lubricant from flowing out of the gap 100a of the hub bearing 100.

[0042] Additionally, the elastomer portion 20 may have, for example, a base portion 24. Figure 2 As shown, the intermediate lip 22 and the grease lip 23 extend from the inner circumferential end of the base portion 24, respectively. Additionally, as... Figure 2 As shown, the side lip 21 is radially separated from the middle lip 22, for example, on a more peripheral side than the middle lip 22, and extends from the base portion 24. The base portion 24 is a portion of the elastomeric portion 20 that extends into the inner surface of the reinforcing ring 10 through the flange portion 13, the fitting portion 11, and the lip support portion 12 of the reinforcing ring 10. Figure 2 , 3 As shown, the base portion 24 has an outer peripheral facing portion 24a that extends as a cylindrical portion along the fitting portion 11 of the reinforcing ring 10, and the aforementioned outer cylindrical surface 3a is formed on the outer peripheral facing portion 24a of the base portion 24. The outer cylindrical surface 3a is, for example, a cylindrical surface or a substantially cylindrical surface with the axis x as its central axis or approximately its central axis. The outer cylindrical surface 3a is not limited to a surface that depicts a straight line parallel to the axis x on a cross-section based on a plane containing the axis x. On a cross-section based on a plane containing the axis x, the outer cylindrical surface 3a may, for example, be a surface that depicts a straight line inclined relative to the axis x, or a surface that depicts a curve, or a surface that depicts a line composed of a combination of a straight line and a curve. Specifically, for example, the outer cylindrical surface 3a may also be a conical surface or a substantially conical surface with the axis x as its central axis or approximately its central axis, which expands inward in the direction of the axis x.

[0043] like Figure 2 As shown, the side lip 21 specifically extends in a ring shape from the base portion 24 toward the inward side, for example, with the axis x as the central axis or approximately the central axis. Additionally, as... Figure 2 As shown, in the operating state of the hub seal 1, where the sealing body 3 and the oil slinger ring 4 are mounted on the hub bearing 100 in a predetermined relative position, the side lip 21 is formed such that its front end has a predetermined tightening allowance and contacts the flange portion 31 of the oil slinger ring 4. Figure 2 As shown, the side lip 21 has, for example, a conical or generally conical shape that expands in diameter toward the inward side in the x-axis direction.

[0044] like Figure 2As shown, the intermediate lip 22 specifically extends inward from the base portion 24 in a ring shape, for example, with the axis x as the central axis or approximately the central axis. Furthermore, in the operating state of the hub seal 1, the intermediate lip 22 is formed such that its front end has a predetermined tightening allowance and contacts the flange portion 31 of the oil slinger ring 4. The intermediate lip 22, for example, has a conical or approximately conical shape that expands inward along the axis x direction. The intermediate lip 22 may extend parallel to the side lip 21, and furthermore... Figure 2 As shown, the intermediate lip 22 may not be parallel to the lateral lip 21; for example, its inclination relative to the axis x may be gentler than that of the lateral lip 21. Conversely, the intermediate lip 22 may also have a stronger inclination relative to the axis x than that of the lateral lip 21. Figure 2 As shown, the grease lip 23 extends in a ring shape from the base portion 24 toward the outer and inner circumferential sides, for example, with the axis x as the central axis or approximately the central axis. The grease lip 23 is formed such that, in the operating state of the hub seal 1, the front end has a predetermined tightening allowance and contacts the fitting portion 34 of the oil slinger ring 4 from the outer circumferential side.

[0045] In addition, such as Figure 2 As shown, an annular protrusion 25 is formed, for example, on the elastomer portion 20. The annular protrusion 25 is an annular protrusion that protrudes inward and surrounds the axis x, located on the outer periphery of the outer cylinder surface 3a. Figure 2 As shown, the annular protrusion 25 extends from the portion of the base portion 24 along the flange portion 13 of the reinforcing ring 10. Figure 2 , 3 As shown, in the operating state of the hub seal 1, the annular protrusion 25 is located further outward than the second gap S2, and the inner end 25a, which is the inner front end, is located further inward than the opening S2a inside the second gap S2. Furthermore, the annular protrusion 25 protrudes obliquely from the outer peripheral end of the base portion 24 towards both the inner and outer peripheral sides.

[0046] In addition, such as Figure 2 As shown, the elastomer portion 20, for example, has a sealing pad portion 26 on a side further outward than the annular protrusion 25. This sealing pad portion 26 is an annular portion protruding outward. Figure 2 As shown, the sealing gasket 26 is formed to contact the outer peripheral surface 101d of the inner opening 101a of the outer ring 101 in the operating state of the hub seal 1. Furthermore, as... Figure 2 As shown, the sealing gasket portion 26 is formed, for example, in a manner that covers the end of the outer peripheral side of the flange portion 13 of the reinforcing ring 10. Additionally, as... Figure 2 As shown, the elastomer portion 20, for example, has a sealing gasket portion 27 that at least partially covers the outer surface of the flange portion 13 of the reinforcing ring 10. The sealing gasket portion 27 extends annularly about the axis x and connects to the inner end of the sealing gasket portion 26. Figure 2As shown, the sealing gasket 27 is formed in such a way that it contacts the inner end face 101e of the inner opening 101a of the outer ring 101 when the hub seal 1 is in use.

[0047] Furthermore, as described above, the elastomer portion 20 has a labyrinthine lip 40. For example... Figure 2 As shown, the labyrinth lip 40 is radially separated from the side lip 21 on a more peripheral side than the side lip 21, and extends from the base portion 24. The labyrinth lip 40 extends toward the barrel portion 32 of the oil-slinging ring 4. Furthermore, the portion of the labyrinth lip 40 on the front end 41 side faces the barrel portion 32 from the inner peripheral side, and a fourth gap S4, forming an annular gap, is formed between this portion of the labyrinth lip 40 on the front end 41 side and the barrel portion 32. Figure 2 As shown, the labyrinthine lip 40 extends in a ring shape from the base portion 24 toward the cylindrical portion 32, for example, with the axis x as the central axis or approximately the central axis. Additionally, as... Figure 2 As shown, in the operating state of the hub seal 1, where the sealing body 3 and the oil slinger ring 4 are mounted on the hub bearing 100 in a predetermined relative position, a labyrinth lip 40 is formed such that the radial width W4 between the front end 41 and the inner circumferential surface 32 of the cylindrical portion 32 (described later) is a predetermined width. The labyrinth lip 40 is inclined relative to the cylindrical portion 32 of the oil slinger ring 4, for example, such that the radial width W4 of the fourth gap S4 at the front end 41 is minimized. Figure 2 As shown, the labyrinth lip 40 specifically has, for example, a conical or generally conical shape that expands inward along the x-axis. The labyrinth lip 40 may extend parallel to the side lip 21, and additionally, as... Figure 2 As shown, the labyrinthine lip 40 may not be parallel to the lateral lip 21; for example, its inclination relative to the axis x may be gentler than that of the lateral lip 21. Alternatively, the labyrinthine lip 40 may be more strongly inclination relative to the axis x than that of the lateral lip 21.

[0048] The elastomer portion 20 is integrally mounted on the reinforcing ring 10. The labyrinth lip 40, side lip 21, middle lip 22, grease lip 23, base portion 24, ring protrusion 25, sealing gasket portion 26, and sealing gasket portion 27 are all integrally formed from the same material and are continuously integrated. Various rubber materials can be used as the elastomer of the elastomer portion 20. Examples of such rubber materials include nitrile rubber (NBR), hydrogenated nitrile rubber (H-NBR), acrylic rubber (ACM), and fluororubber (FKM), among other synthetic rubbers. The elastomer portion 20 is mainly integrally mounted on the reinforcing ring 10 at the base portion 24.

[0049] The oil slinger ring 4 is a ring-shaped or approximately ring-shaped metal plate component with the axis x as its central axis or approximately its central axis, such as... Figure 1 , 2As shown, it is formed such that the inner ring component 104 is pressed into the inner ring 102 of the hub bearing 100 and thus fitted into the inner ring component 104. Figure 2 As shown, the oil slinger 4, for example, in addition to the flange portion 31 and the barrel portion 32, also has a fitting portion 34 formed in such a way that it faces the barrel portion 32 via the flange portion 31.

[0050] like Figure 2 As shown, the fitting portion 34 is, for example, a cylindrical or substantially cylindrical portion with the axis x as its central axis or approximately its central axis, formed in such a way that it is fitted into the outer peripheral surface 104a of the inner ring member 104. Additionally, as... Figure 2 As shown, the contact surface 34a, which faces the outer peripheral side of the fitting portion 34, is, for example, a cylindrical surface or a generally cylindrical surface with the axis x as its central axis or approximately its central axis. The flange portion 31 is a circular or generally circular plate-shaped portion that extends radially with the axis x as its central axis or approximately its central axis, such as... Figure 2 As shown, an annular portion is formed that protrudes radially from the outer peripheral surface 104a of the inner ring member 104. The contact surface 31a, which is the surface facing the inner side of the flange portion 31, is, for example, a surface that extends on a plane that is parallel or substantially parallel to a plane orthogonal to the coaxial axis x.

[0051] like Figure 2 , 3 As shown, the cylindrical portion 32 of the oil slinger 4 is, for example, a generally cylindrical portion extending outward from the outer peripheral end of the flange portion 31, with the axis x as its central axis or approximately its central axis. Figure 3 As shown, the cylindrical portion 32 has an inner cylindrical surface 32a facing the outer periphery. The inner cylindrical surface 32a is, for example, a cylindrical surface or a substantially cylindrical surface with the axis x as its central axis or approximately its central axis. As described above, an annular weir portion 33 protruding outwards is provided at the inner end of the cylindrical portion 32. Figure 3 As shown, the weir 33 is, for example, located on the outer side of the inner cylinder surface 32a and connected to the outer end of the inner cylinder surface 32a. Figure 3 As shown, the weir portion 33 protrudes further outward than the inner cylinder surface 32a, and a weir surface 33b is formed between the end 33a and the inner cylinder surface 32a. The weir surface 33b is an annular surface extending inward from the end 33a around the axis x, facing inward. Additionally, as... Figure 3 As shown, the weir portion 33 has a side surface 33c that is an annular surface facing outwards. The side surface 33c is the surface facing away from the weir surface 33b. The end 33a of the weir portion 33 is the front end of the weir portion 33, as shown... Figure 3 As shown, for example, it is an annular surface facing the outer periphery; specifically, it is a cylindrical surface or a roughly cylindrical surface with the axis x as its central axis or approximately its central axis. Furthermore, the weir surface 33b and the side surface 33c are, for example, surfaces extending on a plane parallel or substantially parallel to a plane orthogonal to the coaxial axis x.

[0052] like Figure 3 As shown, the end 33a of the weir 33 faces the outer cylinder surface 3a of the sealing body 3 radially from the inner circumferential side, and an annular first gap S1 is formed between the end 33a of the weir 33 and the outer cylinder surface 3a. Furthermore, as... Figure 3 As shown, the inner cylinder surface 32a of the cylinder portion 32 faces the outer cylinder surface 3a radially from the inner circumferential side, and an annular second gap S2 is formed between the inner cylinder surface 32a and the outer cylinder surface 3a of the cylinder portion 32. Figure 3 As shown, the outer cylinder surface 3a faces the entire end 33a of the weir 33 and the inner cylinder surface 32a of the cylinder 32 in the radial direction. It should be noted that the outer cylinder surface 3a may also face a portion of the end 33a of the weir 33 and the inner cylinder surface 32a of the cylinder 32 in the radial direction.

[0053] like Figure 3 As shown, the radial width of the first gap S1 is width W1. On the other hand, the radial width of the second gap S2 is width W2. The width W1 of the first gap S1 is narrower than the width W2 of the second gap S2. It should be noted that the width of the gap is, for example, the width at a specific location of the gap (such as the maximum or minimum gap position), or the average value of the widths of gaps at a specified number of locations, etc. Furthermore, as... Figure 3 As shown, the length of the first gap S1 in the x-direction is L1. Conversely, the length of the second gap S2 in the x-direction is L2. The length L1 of the first gap S1 corresponds to the width of the end 33a in the x-direction, and the length L1 of the first gap S1 is the same as the width of the end 33a. Similarly, the length L2 of the second gap S2 corresponds to the width of the inner cylinder surface 32a in the x-direction, and the length L2 of the second gap S2 is the same as the width of the inner cylinder surface 32a.

[0054] Specifically, the width W1 and length L1 of the first gap S1 are the width and length of the labyrinth seal formed facing the liquid foreign object. Thus, the first gap S1 becomes a labyrinth gap S1. It should be noted that the liquid foreign object is rainwater, muddy water, rainwater or muddy water containing dust, etc. The labyrinth seal formed by the gap prevents the liquid foreign object from entering the gap, creating a resistance effect that hinders the liquid foreign object from entering the gap. The width W1 and length L1 of the labyrinth gap S1 are values ​​that generate the aforementioned resistance effect on the liquid foreign object assuming the hub seal 1 is exposed, depending on the applicable object of the hub seal 1. The width W1 and length L1 of the labyrinth gap S1 are set, for example, based on the physical properties of the liquid foreign object assuming the hub seal 1 is exposed, depending on the applicable object of the hub seal 1. These physical properties include, for example, the viscosity or surface tension of the liquid foreign object, the size of the solid foreign objects contained in the liquid foreign object, etc. The aforementioned resistance effect can be confirmed, for example, through tests under simulated operating conditions of the hub seal 1.

[0055] On the other hand, the width W2 and length L2 of the second gap S2 are such that a labyrinth seal is not formed for liquid foreign matter. The second gap S2 can discharge liquid foreign matter flowing into it, thus becoming a discharge gap S2. Specifically, as described above, the discharge gap S2 is formed by dividing the inner cylinder surface 32a of the cylinder 32, the weir surface 33b of the weir 33, the labyrinth gap S1, and the outer cylinder surface 3a. Downstream of the flow of foreign matter flowing into the discharge gap S2, the discharge gap S2 is blocked by the weir surface 33b and the labyrinth gap S1. Therefore, the foreign matter that has flowed into the discharge gap S2 mainly moves downstream along the inner cylinder surface 32a of the cylinder 32 and is bounced back by the weir surface 33b and the labyrinth gap S1. Furthermore, the width W2 and length L2 of the discharge gap S2 are such that a labyrinth seal is not formed for liquid foreign matter. Specifically, the width W2 and length L2 of the discharge gap S2 are values ​​that allow liquid foreign matter bounced back from the weir surface 33b and the labyrinth gap S1 to flow toward the opening S2a of the discharge gap S2. The width W2 and length L2 of the discharge gap S2 are preferably values ​​that suppress interference between the liquid foreign matter bounced back from the weir surface 33b and the labyrinth gap S1 and foreign matter flowing into the discharge gap S2 and moving downstream. Thus, the discharge gap S2 has a discharge function that discharges liquid foreign matter flowing into the discharge gap S2 and bounced back from the weir surface 33b and the labyrinth gap S1 from the opening S2a to the outside of the discharge gap S2. The discharge gap S2 also discharges foreign matter that is not liquid. It should be noted that the discharge gap S2 may also not discharge foreign matter that is not liquid. This discharge function can be confirmed, for example, through tests under simulated operating conditions of the hub seal 1.

[0056] like Figure 3 As shown, the side surface 33c of the weir portion 33 faces the opposing portion 24b from the inside in the x-axis direction. The opposing portion 24b is the part of the base portion 24 extending along the lip flange portion 12b of the reinforcing ring 10. An annular third gap S3 is formed between the side surface 33c of the weir portion 33 and the opposing portion 24b of the base portion 24. The third gap S3 communicates with the labyrinth gap S1. The third gap S3, for example, is a gap that forms a labyrinth seal for liquid foreign matter, similar to the labyrinth gap S1. Specifically, for example, the width W3 in the x-axis direction and the radial length L3 of the third gap S3 are the width and length for forming a labyrinth seal for liquid foreign matter. It should be noted that the length L3 of the third gap S3 corresponds to the radial width of the side surface 33c, and the length L3 of the third gap S3 is the same as the width of the side surface 33c. In this case, the labyrinth gap S1 and the third gap S3 form a labyrinth seal. It should be noted that the third gap S3 can also be a gap that does not form a labyrinth seal for liquid foreign matter.

[0057] like Figure 3As shown, the inner circumferential surface 32b, which is the inner circumferential side facing the cylindrical portion 32, faces radially from the inner circumferential side towards the front end 41 side of the labyrinth lip 40. A fourth gap S4 is formed between the front end 41 side of the labyrinth lip 40 and the cylindrical portion 32. The fourth gap S4 communicates with the third gap S3. The fourth gap S4, for example, is a labyrinth gap that forms a labyrinth seal against liquid foreign matter, similar to the labyrinth gap S1. Specifically, for example, the radial width W4 of the labyrinth gap S4 at the front end 41 of the labyrinth lip 40 is made such that a labyrinth seal is formed at least at the front end 41 of the labyrinth lip 40 that the width of the labyrinth gap S4 at the front end 41 of the labyrinth lip 40 is the width for forming a labyrinth seal against liquid foreign matter. When the third gap S3 forms a labyrinth seal, the labyrinth gap S1, the third gap S3, and the labyrinth gap S4 form a labyrinth seal.

[0058] As described above, a space S5 is formed between the side lip 21 and the cylindrical portion 32 of the oil slinger 4. Specifically, as Figure 2 As shown, space S5 is formed by the cylindrical portion 32 and a portion of the flange portion 31 of the oil-slinging ring 4, the side lip 21, a portion of the opposing portions 24b of the base portion 24, and the labyrinth lip 40. Figure 2 , 3 As shown, space S5 is connected to the outside of discharge gap S2 via labyrinth gap S4, third gap S3, labyrinth gap S1, and discharge gap S2. That is, in hub seal 1, the path to space S5 is formed by discharge gap S2, labyrinth gap S1, third gap S3, and labyrinth gap S4.

[0059] Furthermore, the oil slinger ring 4 is tightly attached to the inner ring component 104. Specifically, the fitting portion 34 of the oil slinger ring 4 and the inner ring component 104 are tightly attached to each other in such a way that no gap is formed between the fitting portion 34 and the inner ring component 104 that allows foreign matter to pass through. It should be noted that the oil slinger ring 4 and the inner ring component 104 may also be loosely attached as described above. In this case, for example, an annular sealing gasket may be provided between the oil slinger ring 4 and the inner ring component 104 to prevent foreign matter from entering the gap 100a between the outer ring 101 and the inner ring 102 through the gap between the oil slinger ring 4 and the inner ring component 104. For example, as Figure 4 As shown, an annular sealing gasket 5, formed of an elastomer and in contact with the outer peripheral surface 104a of the inner ring component 104, can also be provided on the inner peripheral surface 31b of the flange portion 31 of the oil slinger 4. Alternatively, this sealing gasket 5 can also function as an encoder. In this case, as... Figure 4 As shown, in the x-axis direction, the hub seal 1 is configured such that the sealing gasket 5 is covered by the outer cylindrical surface 3a from the outer peripheral side. It should be noted that the hub seal 1 can also be configured such that the sealing gasket 5 is not covered by the outer cylindrical surface 3a from the outer peripheral side, but protrudes further inward than the outer cylindrical surface 3a.

[0060] In addition, such as Figure 5As shown, the inner cylinder surface 32a of the cylinder portion 32 of the oil slinger 4 can also extend obliquely relative to the axis x direction. Specifically, as... Figure 5 As shown, for example, the cylindrical portion 32 of the oil slinger ring 4 can also be formed into a conical trapezoidal shape. That is, as... Figure 5 As shown, the cylindrical portion 32 of the oil slinger 4 can also be a conical or approximately conical cylindrical portion that expands outward in the x-axis direction, and the inner cylindrical surface 32a can also be a conical or approximately conical surface that expands outward in the x-axis direction with the x-axis as the central axis or approximately the central axis. Thus, if the cylindrical portion 32 of the oil slinger 4 is a conical trapezoid, and the inner cylindrical surface 32a of the cylindrical portion 32 is a conical surface that expands outward from the flange portion 31, the discharge effect of the discharge gap S2 can be strengthened.

[0061] The oil slinger ring 4 is integrally formed, for example, from a metal sheet of the same thickness by stamping or forging. The cylindrical portion 32, the flange portion 31, and the fitting portion 34 are integrally formed parts of the oil slinger ring 4. The metal material for the oil slinger ring 4 may include, for example, stainless steel or SPCC (cold-rolled steel). The weir portion 33 is formed, for example, by bending the outer end of the cylindrical portion 32.

[0062] The hub seal 1 has the configuration described above. In the path from the opening S2a of the discharge gap S2 to the space 100a of the hub bearing 100, a labyrinth gap S1 is provided upstream of the side lip 21 to resist the entry of liquid foreign matter. Therefore, the hub seal 1 can prevent liquid foreign matter from reaching the contact portion between the side lip 21 and the flange portion 31 of the oil slinger ring 4. Furthermore, a discharge gap S2 is provided upstream of the labyrinth gap S1 to discharge liquid foreign matter. This also prevents liquid foreign matter from reaching the contact portion between the side lip 21 and the flange portion 31 of the oil slinger ring 4. Additionally, when a labyrinth seal is formed by a third gap S3, the hub seal 1 can also prevent liquid foreign matter from reaching the contact portion between the side lip 21 and the flange portion 31 of the oil slinger ring 4 through this third gap S3. Furthermore, a labyrinth gap S4 is provided upstream of the side lip 21 to resist the entry of liquid foreign matter. Therefore, the hub seal 1 can also prevent liquid foreign matter from reaching the contact area between the side lip 21 and the flange 31 of the oil slinger 4 through the labyrinth gap S4.

[0063] As described above, in the hub seal 1, liquid foreign matter is prevented from reaching the contact portion between the side lip 21 and the flange portion 31 of the oil slinger 4, and the side lip 21 is prevented from being exposed to liquid foreign matter. Therefore, liquid foreign matter is prevented from reaching the contact portion between the intermediate lip 22 and the flange portion 31 of the oil slinger 4, and the intermediate lip 22 is prevented from being exposed to liquid foreign matter. This improves the sealing performance of the side lip 21 and the intermediate lip 22 against liquid foreign matter.

[0064] Thus, the hub seal 1 according to this embodiment can improve the sealing performance against liquid foreign matter.

[0065] Furthermore, the labyrinth gap S1, discharge gap S2, third gap S3, and labyrinth gap S4 prevent the sealing body 3 from contacting the oil slinger ring 4, thus inhibiting the entry of liquid foreign matter and improving the sealing performance of the hub seal 1 against liquid foreign matter. In other words, the hub seal 1 can improve its sealing performance against liquid foreign matter without increasing torque resistance.

[0066] Furthermore, as described above, the labyrinth gap S1, discharge gap S2, third gap S3, and labyrinth gap S4 inhibit liquid foreign matter from reaching the contact portions between the side lip 21 and the middle lip 22 and the flange portion 31 of the oil slinger 4. Therefore, there are cases where the necessary sealing performance can be maintained even with a reduced tightening allowance of the side lip 21 against the flange portion 31, and there are also cases where the necessary sealing performance can be maintained even with a reduced tightening allowance of the middle lip 22 against the flange portion 31. Thus, the hub seal 1 can reduce torque resistance while maintaining the necessary sealing performance.

[0067] In addition, as described above, the hub seal 1 has an annular protrusion 25, making it difficult for foreign objects to enter the discharge gap S2.

[0068] Next, the hub seal 2 according to the second embodiment of the present invention will be described. Figure 6 yes Figure 1 A partially enlarged cross-sectional view near the hub seal 2 in the image. Figure 7 yes Figure 6 A partially enlarged cross-sectional view of the hub seal 2 in the image. Figure 6 The diagram shows a cross-section of hub seal 2 relative to one side of the axis x. Hub seal 2 differs from hub seal 1 primarily in the shape of the oil slinger ring. Hereinafter, regarding the configuration of hub seal 2, configurations identical to or having the same function as hub seal 1 will be labeled with the same symbols and their descriptions will be omitted; different configurations will be described.

[0069] Hub seal 2 is the outer hub seal, such as... Figure 1 , 6 As shown, the outer opening 101b of the outer ring 101 of the hub bearing 100 is installed between the hub ring 105 and the outer ring 101. Therefore, the configurations of the hub seal 2 installed on the hub bearing 100 are reversed relative to the corresponding configurations of the hub seal 1 installed on the hub bearing 100, with the inner side becoming the outer side and the outer side becoming the inner side, and the orientation in the x-axis direction being opposite. Figure 6As shown, the hub seal 2 has a sealing body 3 and an oil slinger 6. The oil slinger 6 differs from the oil slinger 4 primarily in that it has a flange portion 35 with a different shape than the flange portion 31 of the oil slinger 4 in the hub seal 1. The sealing body 3 of the hub seal 2 corresponds to the structure of the portion of the hub bearing 100 to which it is mounted, and its specific dimensions and shape differ from those of the sealing body 3 of the hub seal 1. Similarly, the oil slinger 6 of the hub seal 2 corresponds to the structure of the portion of the hub bearing 100 to which it is mounted, and its specific dimensions and shape differ from those of the oil slinger 4 of the hub seal 1.

[0070] like Figure 6 , 7 As shown, the reinforcing ring 10 of the hub seal 2 is formed in such a way that it is pressed into and fitted into the through hole 107 of the outer ring 101 of the hub bearing 100. For example, the fitting part 11 is formed in such a way that it is pressed into the outer opening 101b of the outer ring 101 and fitted into its inner circumferential surface 101f.

[0071] like Figure 6 As shown, the side lip 21 and the middle lip 22 of the hub seal 2 extend outward from the base portion 24. In the operating state of the hub seal 2, where the sealing body 3 and the oil slinger ring 6 are mounted on the hub bearing 100 in a predetermined relative position, the side lip 21 and the middle lip 22 are formed such that their front ends have a predetermined tightening allowance and contact the flange portion 35 of the oil slinger ring 6. The grease lip 23 extends inward and towards the inner circumferential side from the base portion 24. The grease lip 23 is formed such that, in the operating state of the hub seal 2, its front end has a predetermined tightening allowance and contacts the fitting portion 34 of the oil slinger ring 6 from the outer circumferential side.

[0072] In addition, such as Figure 6 As shown, the labyrinth lip 40 extends from the base portion 24 toward the cylindrical portion 32. In the operating state of the hub seal 2, where the sealing body 3 and the oil slinger ring 6 are mounted on the hub bearing 100 in a predetermined relative position, the labyrinth lip 40 is formed such that the radial width W4 between the front end 41 and the inner circumferential surface 32b of the cylindrical portion 32 is a predetermined width. The labyrinth lip 40 is inclined relative to the cylindrical portion 32 of the oil slinger ring 4, for example, in such a way that the radial width W4 of the labyrinth gap S4 at the front end 41 is minimized.

[0073] In addition, such as Figure 6 As shown, the annular protrusion 25 protrudes outward, for example, from the end of the base portion 24 on the outer periphery side, protruding obliquely outward and towards the outer periphery side. Furthermore, in the operating state of the hub seal 2, the annular protrusion 25, as... Figure 6 As shown, for example, it is formed such that its front end faces the side 105f of the wheel mounting flange 105b with a gap between them. Figure 6As shown, the sealing gasket portion 26 of the hub seal 2 is formed in such a way that it contacts the outer peripheral surface 101g of the outer opening portion 101 of the outer ring 101 when the hub seal 2 is in use. Figure 6 As shown, the sealing gasket portion 27 of the hub seal 2 is formed in such a way that it contacts the outer end face 101h of the outer opening portion 101b of the outer ring 101 when the hub seal 2 is in use.

[0074] The oil slinger ring 6 is a ring-shaped or approximately ring-shaped metal plate component with the axis x as its central axis or approximately its central axis, such as... Figure 6 As shown, it is formed by pressing into and fitting into the inner ring 102 of the wheel hub bearing 100. Figure 6 As shown, the fitting portion 34 of the oil slinger 6 is formed, for example, by fitting into the outer peripheral surface 105e of the shaft portion 105a of the hub ring 105.

[0075] like Figure 6 As shown, the flange 35 of the oil slinger 6 has a shape corresponding to the side surface 105f near the root of the wheel mounting flange 105b of the hub rim 105. For example... Figure 6 As shown, for example, the cross-sectional shape of the flange portion 35 based on the plane including the axis x is a convex shape that is smoothly curved inward to the inner peripheral side. In addition, the cross-sectional shape of the contact surface 35a, which is the surface facing the inner and outer peripheral sides of the flange portion 35, based on the plane including the axis x, is a convex curve that is smoothly curved outward and inward to the inner peripheral side, and the contact surface 35a of the flange portion 35 is smoothly connected to the contact surface 34a of the fitting portion 34.

[0076] like Figure 6 , 7 As shown, the cylindrical portion 32 of the oil slinger 6 extends inward from the end of the outer periphery of the flange portion 35, for example. The cylindrical portion 32 has a weir portion 33, as is also present in the hub seal 2. Figure 6 , 7 As shown, the end 33a of the weir 33 faces the outer cylindrical surface 3a of the sealing body 3 radially from the inner circumference side, and an annular labyrinth gap S1 is formed between the end 33a of the weir 33 and the outer cylindrical surface 3a. Additionally, as... Figure 6 , 7 As shown, the inner cylinder surface 32a of the cylinder portion 32 faces the outer cylinder surface 3a radially from the inner circumferential side, and a discharge gap S2 is formed between the inner cylinder surface 32a and the outer cylinder surface 3a of the cylinder portion 32. In the hub seal 2, as... Figure 6 As shown, the outer cylinder surface 3a faces radially toward the end 33a of the weir 33 and a portion of the inner cylinder surface 32a of the cylinder 32. It should be noted that the outer cylinder surface 3a may also face radially toward the entire end 33a of the weir 33 and the inner cylinder surface 32a of the cylinder 32.

[0077] In addition, such as Figure 6 , 7 As shown, the side 33c of the weir portion 33 of the hub seal 2 faces inward, and the side 33c faces the opposing portion 24b of the base portion 24 from the outside in the x-axis direction. An annular third gap S3 is formed between the side 33c of the weir portion 33 and the opposing portion 24b of the base portion 24.

[0078] In hub seal 2, also as Figure 7 As shown, the radial width and x-axis length of the labyrinth gap S1 are width W1 and length L1, respectively, and the labyrinth gap S1 acts as a resistance to liquid foreign matter. Similarly, the radial width and x-axis length of the discharge gap S2 are width W2 and length L2, respectively. The discharge gap S2 does not form a labyrinth seal for liquid foreign matter, but it discharges liquid foreign matter that flows into the discharge gap S2 and is bounced back by the weir surface 33b and the labyrinth gap S1 from the opening S2a to the outside of the discharge gap S2. Furthermore, the radial width of the labyrinth gap S4 at the front end 41 of the labyrinth gap 40 is width W4, and the labyrinth gap S4 acts as a resistance to liquid foreign matter. Finally, the width in the x-axis direction and the radial length of the third gap S3 are width W3 and length L3, respectively, and the third gap S3 forms a labyrinth seal for liquid foreign matter. It should be noted that the third gap S3 can also be a gap that does not form a labyrinth seal for liquid foreign matter.

[0079] As described above, hub seal 2 has the same structure as hub seal 1 and functions in the same way as hub seal 1.

[0080] Thus, the hub seal 2 according to this embodiment can improve the sealing performance against liquid foreign matter.

[0081] It should be noted that, similar to hub seal 1, as... Figure 8 As shown, the inner cylinder surface 32a of the cylinder portion 32 of the oil slinger 6 can also extend obliquely relative to the axis x in the cross-section. Specifically, as... Figure 8 As shown, for example, the cylindrical portion 32 of the oil slinger ring 6 can also be formed into a conical trapezoidal shape. That is, as... Figure 8 As shown, the cylindrical portion 32 of the oil slinger 6 can also be a conical or approximately conical cylindrical portion that expands inward along the x-axis in cross-section, and the inner cylindrical surface 32a can also be a conical or approximately conical surface that expands inward along the x-axis with the x-axis as its central axis or approximately its central axis. Thus, if the cylindrical portion 32 of the oil slinger 6 is a conical trapezoid, and the inner cylindrical surface 32a of the cylindrical portion 32 is a conical surface that slopes inward from the flange portion 31 toward the outer periphery, the discharge effect of the discharge gap S2 can be strengthened.

[0082] The present invention has been described above through the above embodiments, but the technical scope of the present invention is not limited to the scope described in the above embodiments. It will be apparent to those skilled in the art that various modifications or improvements can be made to the above embodiments. It is evident from the claims that such modifications or improvements can also be included within the technical scope of the present invention.

[0083] The embodiments described above are for the purpose of facilitating understanding of the present invention and are not intended to limit or explain the present invention. Furthermore, the above embodiments do not limit the scope of application of the present invention; the present invention can include all objects as its scope of application. The constituent elements, their arrangement, materials, conditions, shapes, and dimensions, etc., provided in the above embodiments are not limited to the examples and can be appropriately modified. For example, the present invention includes variations arising from manufacturing tolerances, etc. Furthermore, within the scope of technical non-contradiction, the constituent elements shown in different embodiments can be partially substituted or combined with each other. Additionally, the various components can be appropriately and selectively combined to achieve at least a portion of the aforementioned problems and effects.

[0084] For example, the outer cylinder surface 3a can also be formed by the fitting portion 11 of the reinforcing ring 10. In this case, the base portion 24 of the elastomer portion 20 does not have the outer peripheral facing portion 24a. Furthermore, for example, the elastomer portion 20 of the hub seals 1 and 2 may not have the annular protrusion 25, nor may it have the sealing gasket portion 26 or 27. Additionally, for example, if the elastomer portion 20 does not have the annular protrusion 25, the sealing gasket portion 26, and the sealing gasket portion 27, the reinforcing ring 10 of the hub seals 1 and 2 may also not have the flange portion 13.

Claims

1. A sealing device that seals a gap between an outer peripheral component and an inner peripheral component that are rotatable relative to each other about their axes, the inner peripheral component being at least partially surrounded by the outer peripheral component, the sealing device comprising: The sealing device body is fixed to the outer peripheral component; and An oil slinger ring, which is fixed to the inner circumferential component. The sealing device body comprises: an annular reinforcing ring surrounding the axis; and an annular elastomeric portion formed of an elastomeric body mounted on the reinforcing ring and surrounding the axis. The oil-slinging ring comprises: an annular portion, which is a ring-shaped portion extending radially around the axis; and a cylindrical portion, which is a cylindrical portion extending along the axis in the axial direction from the outer peripheral end of the annular portion. An outer cylindrical surface is formed on the main body of the sealing device. The outer cylindrical surface is an annular cylindrical surface extending along the axis. The elastomer portion has a lateral lip and a labyrinthine lip. The cylindrical portion of the oil-slinging ring is located on the outer periphery side of the labyrinth lip. The side lip extends toward the opposite side in the axial direction and contacts the oil-slinging ring. The labyrinth lip extends towards the cylindrical portion of the oil-slinging ring from a more peripheral side than the side lip. The cylindrical portion of the oil-throwing ring has a weir portion at one end, the weir portion being an annular portion extending toward the outer periphery. The outer cylindrical surface of the sealing device body faces at least a portion of the end of the cylindrical portion of the oil slinger ring, including the weir portion, from its outer peripheral side, forming a first gap between the outer cylindrical surface and the end of the weir portion. Additionally, a second gap is formed between the outer cylindrical surface and the portion of the cylindrical portion that is not the weir portion. The weir portion faces the portion of the elastic body portion from the other side, forming a third gap between the weir portion and the portion of the elastic body portion. A portion of the labyrinth lip faces the cylindrical portion of the oil-slinging ring from its inner circumferential side, forming a fourth gap between the labyrinth lip and the cylindrical portion of the oil-slinging ring. The space between the cylindrical portion of the oil-throwing ring and the side lip is connected to the outside of the second gap via the fourth gap, the third gap, the first gap, and the second gap.

2. The sealing device according to claim 1, wherein, The radial width of the fourth gap is the width required to form a labyrinth seal for liquid foreign matter.

3. The sealing device according to claim 2, wherein, The labyrinth lip is inclined relative to the cylindrical portion of the oil-slinging ring in such a way that the radial width of the fourth gap at the front end is minimized.

4. The sealing device according to claim 1, wherein, The radial width of the first gap is narrower than the radial width of the second gap.

5. The sealing device according to claim 4, wherein, The radial width of the first gap is the width required to form a labyrinth seal for the liquid foreign matter. The radial width of the second gap is such that it does not form a labyrinth seal against liquid foreign matter.

6. The sealing device according to claim 1, wherein, Foreign objects that flow into the second gap can be discharged from the second gap.

7. The sealing device according to claim 6, wherein, The weir has a weir surface, which is an annular surface extending from the end toward the inner circumference and surrounding the axis, facing the other side. The cylindrical portion has an inner cylindrical surface, which is a cylindrical surface extending from the inner circumferential side of the weir surface to the other side and facing the outer circumferential side.

8. The sealing device according to claim 1, wherein, The end of the weir is an annular surface facing outwards around the axis.

9. The sealing device according to claim 1, wherein, The elastomer portion has a middle lip extending toward the oil-slinging ring on a more inner circumferential side than the side lip.

10. The sealing device according to claim 9, wherein, The elastomer portion has a grease lip that extends from a side further than the intermediate lip and contacts the oil-slinging ring.

11. The sealing device according to claim 1, wherein, The one side is the inner side. The sealing device is an external sealing device.

12. The sealing device according to claim 1, wherein, The "one side" refers to the outer side. The sealing device is an internal sealing device.

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