Wheel bearing device

Abstract

To provide a wheel bearing device capable of maintaining a bearing performance for a long time by ensuring suppression of movement of a slinger in an axial direction and sealability without requiring an additional processing step.SOLUTION: A wheel bearing device comprises: an inner member consisting of an outer ring 2 including double rows of outside raceway surfaces 2a and 2a in an inner periphery, a hub ring 3 including one inside raceway surface 3d opposed to the outside raceway surface 2a and a wheel fitting flange 3b in an outer periphery and an inner ring 4 coupled to the hub ring 3 and including another inside raceway surface 4a opposed to the outside raceway surface 2a in an outer periphery; double rows of rolling bodies 5 stored between both the raceway surfaces so as to be freely rolled; and an inner side seal member 6 and an outer side seal member 7 sealing the outer ring 2, the hub ring 3 and the inner ring 4. The outer side seal member 7 includes an annular slinger 17, which is fitted to the hub ring 3, and in the slinger 17, a projection 17e formed from an elastic member is provided.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to a wheel bearing device. [Background technology]

[0002] 2. Description of the Related Art Wheel bearing devices that rotatably support wheels in suspension systems for vehicles such as automobiles are known.

[0003] A conventional wheel bearing device comprises an outer ring as an outer member, a hub wheel and an inner ring as inner members, two rolling rows (an inner ball row and an outer ball row), an inner seal member and an outer seal member.

[0004] The inner seal member and the outer seal member are sealing mechanisms that seal (close) the gap between the opening of the outer member and the outer peripheral surface of the inner member, and are, for example, configured as a two-side lip type seal in which two seal lips are in contact or close to each other. The outer seal member is known to have a configuration having an annular slinger. The slinger is formed by bending the outer and inner edge portions of an annular steel plate by press working, so that the slinger is formed into a substantially L-shape in cross section viewed in a direction perpendicular to the axial direction. Specifically, the slinger is configured as an annular member having a cylindrical portion and a standing portion extending radially outward from an end of the cylindrical portion.

[0005] In order to prevent the slinger from moving in the axial direction (toward the inner side) when repeatedly subjected to load or vibration, in conventional patent documents, a movement prevention part is provided on the fitting surface on the inner member side or on the cylindrical part of the slinger. For example, a configuration in which a slip-out prevention part is formed on the hub wheel shoulder part and protrudes radially beyond the slinger fitting part is known (for example, see Patent Document 1).

[0006] As a movement prevention portion, for example, a configuration in which a protrusion is formed on the hub wheel shoulder portion so that a slip-out prevention portion that protrudes radially beyond the cylindrical portion of the slinger can be formed by crimping the protrusion is known (see, for example, Patent Document 2).

[0007] In addition, a known configuration for preventing movement is one in which the slinger cylindrical portion has a bent portion, and a slip-out prevention portion is formed in the hub wheel shoulder portion, protruding radially beyond the slinger fitting portion (see, for example, Patent Document 3). [Prior art documents] [Patent documents]

[0008] [Patent Document 1] JP 2014-240679 A [Patent Document 2] Patent Publication No. 2021-085412 [Patent Document 3] JP 2017-129197 A Summary of the Invention [Problem to be solved by the invention]

[0009] However, as in the conventional document, when a protruding retaining portion is formed on the shoulder of the hub wheel as a movement prevention portion, the cylindrical portion of the slinger may undergo plastic deformation in the radial direction, which may reduce the engagement force with the hub wheel. In addition, in the configuration in which the slinger is crimped after being pressed in, the process becomes more complicated, which increases costs. In addition, when a bent portion is formed on the cylindrical portion, the rigidity of the slinger increases, which increases the press-in force when it passes the retaining portion. In addition, the slinger may be scraped off by the step of the small diameter portion of the hub wheel, which may allow foreign matter to enter the inside of the bearing. In addition, when the slinger moves to the inner side in the axial direction, muddy water may enter through the gap between the hub wheel and the slinger, which may cause rust or cause muddy water to enter the inside of the bearing through the fitting portion.

[0010] Therefore, the present invention has been made in consideration of the above-mentioned circumstances, and provides a wheel bearing device that does not require additional processing steps, suppresses axial movement of the slinger, ensures sealing, and can maintain bearing performance over a long period of time. [Means for solving the problem]

[0011] That is, the wheel bearing device is a wheel bearing device comprising an inner member composed of an outer member having a double-row outer raceway surface on its inner circumference, a hub wheel having on its outer circumference one inner raceway surface facing the outer raceway surface and a wheel mounting flange for mounting a wheel, and a raceway surface forming member connected to the hub wheel and having on its outer circumference the other inner raceway surface facing the outer raceway surface, double-row rolling elements accommodated so as to roll freely between both raceway surfaces of the outer member and the inner member, and a seal member for sealing between the outer member and the inner member, wherein the seal member is an outer side seal member and has a circular slinger that fits into the hub wheel, and a protrusion is provided at the inner side end of the fitting surface of the slinger with the hub wheel, and the protrusion is formed from an elastic member. Effect of the Invention

[0012] According to the present invention, by providing the slinger with a protrusion formed from an elastic material, no additional processing steps are required, and axial movement of the slinger can be suppressed and sealing performance can be ensured, thereby maintaining bearing performance over a long period of time. [Brief description of the drawings]

[0013] [Figure 1] 1 is a side cross-sectional view showing a wheel bearing device according to an embodiment of the present invention. [Diagram 2] FIG. 2 is an enlarged cross-sectional view of a hub wheel according to a first embodiment, where (A) is an enlarged cross-sectional view of a hub wheel provided with a recess, and (B) is a side cross-sectional view of a hub wheel without a recess. [Diagram 3] FIG. 2 is an enlarged side view showing an outer seal member according to the first embodiment. [Figure 4]3 is a side cross-sectional view showing the hub wheel and outer seal member according to the first embodiment. FIG. [Diagram 5] 2 is a side cross-sectional view showing the hub wheel, outer seal member, and outer ring according to the first embodiment. FIG. [Figure 6] 5(A) to 5(C) are side cross-sectional views showing a process of press-fitting the slinger into the hub wheel according to the first embodiment. [Figure 7] FIG. 3 is an enlarged cross-sectional view showing a recess according to the first embodiment. [Figure 8] FIG. 2A is a side cross-sectional view showing a slinger according to a first embodiment, and FIG. 2B is a side cross-sectional view showing a slinger according to a second embodiment. [Figure 9] 13 is a side cross-sectional view showing a hub wheel, an outer seal member, and an outer ring according to a third embodiment. FIG. [Figure 10] FIG. 2 is a side cross-sectional view showing a wheel bearing device having a fourth-generation structure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.

[0015] [Wheel bearing device] The overall configuration of the wheel support bearing device 1 will be described with reference to Figure 1. In the following description, the inner side refers to the vehicle body side of the wheel support bearing device 1 when it is attached to the vehicle body, and the outer side refers to the wheel side of the wheel support bearing device 1 when it is attached to the vehicle body. The axial direction refers to the direction along the rotation axis of the wheel support bearing device 1. The radial direction refers to the direction perpendicular to the rotation axis. The axial outer side is synonymous with the outer side, and the axial inner side is synonymous with the inner side.

[0016] As shown in Fig. 1, a wheel bearing device 1 rotatably supports a wheel in a suspension system of a vehicle such as an automobile. The wheel bearing device 1 includes an outer ring 2 as an example of an outer member, a hub ring 3 and an inner ring 4 as examples of inner members, a rolling element 5, an inner seal member 6, and an outer seal member 7. The outer member and the inner member are examples of raceways.

[0017] The outer ring 2 supports the hub ring 3 and the inner ring 4. An inner circumferential surface at an inner end 2g of the outer ring 2 is provided with an inner fitting surface 2b into which an inner seal member 6 is fitted. An inner circumferential surface at an outer end 2f of the outer ring 2 is provided with an outer fitting surface 2c into which an outer seal member 7 is fitted. A vehicle body mounting flange 2d for mounting to a knuckle of a suspension system is integrally formed on an outer circumferential surface 2e of the outer ring 2. Double row outer raceways 2a·2a are provided circumferentially on the inner and outer sides of the inner circumferential surface of the outer ring 2.

[0018] The hub wheel 3 rotatably supports a wheel and a brake rotor (or a brake drum) of a vehicle (not shown). An axially extending small-diameter step 3a is provided at the inner end of the outer circumferential surface of the hub wheel 3. A wheel mounting flange 3b for mounting a wheel is integrally provided at the outer end of the hub wheel 3. A hub bolt for fastening the hub wheel 3 to a wheel or a brake device is press-fitted into the wheel mounting flange 3b.

[0019] The wheel mounting flange 3b may also be provided with tapped holes for fastening hub bolts. The outer peripheral surface of the outer side of the hub wheel 3 is provided with an inner raceway surface 3d that faces the outer raceway surface 2a. In other words, the inner raceway surface 3d is formed by the hub wheel 3 on the outer side of the inner member. The base side of the wheel mounting flange 3b of the hub wheel 3 is provided with a fitting surface 3e into which the outer seal member 7 fits. Strictly speaking, the fitting surface 3e is the surface into which the fitting portion 17a of the slinger 17 constituting the outer seal member 7 fits.

[0020] 2, the fitting surface 3e is formed on the outer peripheral surface of the hub wheel 3, and an outer side portion 3h of the fitting surface 3e of the outer side seal member is formed continuous with a base portion 3f of the wheel mounting flange 3b, and an inner side end portion 3i is formed continuous with the inner raceway surface 3d. The base portion 3f is formed into an arcuate cross section at the corner between the fitting surface 3e of the hub wheel 3 and the wheel mounting flange 3b.

[0021] The outer diameter dh1 of the outer portion 3h of the fitting surface 3e of the outer seal member is larger than the inner diameter of the fitting portion 17a of the slinger 17.

[0022] The outer diameter dh2 at the inner end 3i of the fitting surface 3e of the hub wheel 3. The outer diameter dh2 at the inner end 3i is a portion having a smaller diameter than the inner diameter of the fitting portion 17a of the slinger 17.

[0023] Therefore, the outer diameter dh1 of the outer side portion 3h of the hub wheel 3 and the outer diameter dh2 of the inner side end portion 3i are dh1>dh2 Satisfy the relationship.

[0024] 2(A), a recess 3j may be provided in the axial midway portion of the fitting surface 3e. That is, the recess 3j is provided between the inner end portion of the outer portion 3h and the outer side of the inner end portion 3i.

[0025] The outer diameter of the recess 3j is dh3. The outer diameter dh2 of the inner end portion 3i and the outer diameter dh3 of the recess 3j are dh2>dh3 Satisfy the relationship. With this configuration, the outer diameter dh3 of the recess 3j can be formed in the middle of the fitting surface 3e to be smaller than the outer diameter dh2 of the other portions, particularly the inner end portion 3i.

[0026] 2(B), a configuration may be adopted in which no recess is provided in the axial midway portion of the fitting surface 3e. In this case, the inner end portion of the outer portion 3h and the outer end portion of the inner end portion 3i are connected by an inclined portion 3k.

[0027] In this way, by making the outer diameter dh2 of the inner end portion 3i smaller than the outer diameter of the outer portion 3h of the hub wheel 3, elastic-plastic deformation in the radial direction when the slinger 17 is pressed in can be reduced.

[0028] The inner ring 4 is an example of a raceway surface forming member, and is press-fitted into the small diameter step portion 3a of the hub wheel 3. The inner ring 4 applies a preload to the rolling elements 5. The outer circumferential surface of the inner ring 4 is provided with an inner raceway surface 4a that faces the outer raceway surface 2a. In other words, the inner raceway surface 4a is formed by the inner ring 4 on the inner side of the inner member. Also, the outer circumferential surface at the inner end portion 4c of the inner ring 4 is provided with a fitting surface 4b into which the inner seal member 6 is fitted. Also, at the inner end portion of the hub wheel 3, a crimped portion 3l is formed by crimping the inner end face of the inner ring 4.

[0029] The rolling elements 5 are balls. The inner rolling elements 5 and the outer rolling elements 5 are held by cages 51, respectively. The inner rolling elements 5 are rollably sandwiched between the inner raceway surface 4a of the inner ring 4 and the outer raceway surface 2a of the outer ring 2. The outer rolling elements 5 are rollably sandwiched between the inner raceway surface 3d of the hub ring 3 and the outer raceway surface 2a of the outer ring 2. That is, the inner rolling elements 5 and the outer rolling elements 5 are rollably accommodated between the raceway surfaces of the outer member and the inner member. In this way, in the wheel bearing device 1, the outer ring 2, the hub ring 3, the inner ring 4, and the double-row rolling elements 5 form a double-row angular ball bearing. Note that the wheel bearing device 1 may be formed of a double-row tapered roller bearing instead of the double-row angular ball bearing.

[0030] The inner side seal member 6 and the outer side seal member 7 are seal members that close the open ends of the annular space S formed by the outer member and the inner member. The inner side seal member 6 is attached to the inner side open end of the annular space S formed between the outer ring 2 and the inner ring 4. On the other hand, the outer side seal member 7 is attached to the outer side open end of the annular space S formed between the outer ring 2 and the hub wheel 3.

[0031] [Sealing material composition] The inner seal member 6 is configured as a so-called pack seal, which is made up of a slinger 11 and an annular seal plate 12, which are arranged opposite each other. The slinger 11 is made of an austenitic stainless steel plate (JIS standard SUS304, etc.) or an anti-rust treated cold rolled steel plate (JIS standard SPCC, etc.) and formed by pressing to have a substantially L-shaped cross section, and is made up of a cylindrical portion 11a that is press-fitted into the inner ring 4, and a standing plate portion 11b that extends radially outward from the cylindrical portion 11a.

[0032] On the other hand, the seal plate 12 is attached to the inner fitting surface 2b of the outer ring 2 facing the slinger 11, and is formed with a generally L-shaped cross section. It comprises a core metal 13 that is fitted into the end of the inner fitting surface 2b, and a seal portion 14 that is vulcanization bonded to the core metal 13. The core metal 13 is formed by pressing an austenitic stainless steel plate or a rust-proofed cold-rolled steel plate.

[0033] The seal portion 14 is made of synthetic rubber such as NBR (acrylonitrile-butadiene rubber), is bonded integrally to the core metal 13 by vulcanization adhesion, and has a side lip and a radial lip that come into sliding contact with the slinger 11.

[0034] In addition, examples of the material for the seal portion 14 include, in addition to the above-mentioned NBR, HNBR (hydrogenated acrylonitrile butadiene rubber) and EPDM (ethylene propylene rubber), which have excellent heat resistance, as well as ACM (polyacrylic rubber), FKM (fluororubber), and silicone rubber, which have excellent heat and chemical resistance.

[0035] 3, the outer seal member 7 is configured as an integrated seal consisting of a core 15 that is press-fitted onto the inner circumference of the outer ring 2, and a seal portion 16 that has multiple seal lips and is integrally joined to the core 15 by vulcanization adhesion. In this embodiment, a slinger 17 is fitted to the base of the inner side of the wheel mounting flange 3b, and the seal portion 16 is disposed so as to face this slinger 17.

[0036] The core bar 15 is formed by pressing a corrosion-resistant steel plate, such as an austenitic stainless steel plate or a rust-proofed cold-rolled steel plate, and has a cylindrical fitting portion 15a that is fitted into the outer fitting surface 2c of the outer ring 2 and is bent so as to overlap, and an inner portion 15b that is bent from this fitting portion 15a and extends radially inward.

[0037] On the other hand, the seal portion 16 is made of synthetic rubber such as NBR and is fixed to the range extending from the inner end of the inner portion 15b of the core metal 15 to the fitting portion 15a. The seal portion 16 is formed at an inclination radially outward from the inner portion 15b of the core metal 15, and has a first side lip 16a facing a disk portion 17c of the slinger 17 described later, a second side lip 16b in sliding contact with the slinger 17 with a predetermined axial interference, and a radial lip 16c extending at an inward inclination radially from the inner diameter side end of the inner portion 15b. This radial lip 16c is in sliding contact with the outer circumferential surface of the fitting portion 17a of the slinger 17 with a predetermined radial interference, and prevents the grease sealed inside the bearing from leaking out to the outside.

[0038] Furthermore, the seal portion 16 is provided with an outer diameter side fitting protrusion 16d that protrudes radially outward from the axially outer (outer side) end of the fitting portion of the core metal 15. The outer diameter side fitting protrusion 16d is a portion that fits into the outer side fitting surface 2c of the outer ring 2 while elastically deforming, and is a member that enhances sealing performance and also has a function of preventing it from coming off. The outer diameter side fitting protrusion 16d is tapered so that the axial end face is inclined. This makes it possible to reduce resistance when fitting the core metal 15 and the seal portion 16 into the outer side fitting surface 2c of the outer ring 2.

[0039] The slinger 17 is formed by pressing a corrosion-resistant steel plate, such as an austenitic stainless steel plate, a ferritic stainless steel plate (such as JIS standard SUS430 series), or a rust-proofed cold-rolled steel plate, and has a cylindrical fitting portion 17a that is fitted onto the fitting surface 3e of the hub wheel 3, a bent portion 17b that connects the fitting portion 17a and the disc portion 17c, and a disc portion 17c that extends radially outward from the bent portion 17b and is in close contact with the inner side surface of the wheel mounting flange 3b.

[0040] The surface roughness of the steel plate used for the slinger 17 is set to a range of Ra 0.2 to 0.6. This makes it possible to obtain a good seal sliding surface, suppress lip wear, and maintain the sealing performance of the outer seal member 7 even when used in a poor environment. Furthermore, by subjecting the surface of the slinger 17 to a friction coefficient reduction treatment such as molybdenum coating, lip wear can be further suppressed and the seal torque can be reduced. Note that Ra is one of the JIS roughness shape parameters (JIS B0601-1994), and refers to the arithmetic mean roughness, which means the average value of the absolute deviation from the mean line.

[0041] Furthermore, a protrusion 17e is fixed to the inner end of the fitting portion 17a of the slinger 17. The protrusion 17e is a portion that protrudes toward the inner diameter side from a protrusion base 17f that is bonded to the slinger 17. The protrusion 17e and the protrusion base 17f are made of synthetic rubber such as NBR or FKM and are integrally formed.

[0042] Furthermore, a step 17h is provided on the inner end surface of the slinger 17 where the protrusion base 17f is provided. A part of the protrusion base 17f is wedged into the step 17h. This improves the adhesive strength of the protrusion base 17f and the protrusion 17e, which are made of an elastic member, to the slinger 17. The protrusion 17e is formed in an annular shape and protrudes further inward than the fitting portion 17a.

[0043] The inner diameter ds1 of the end surface of the inner diameter side of the protrusion portion 17e and the inner diameter ds2 of the end surface of the inner diameter side of the protrusion base portion 17f are ds2 ≧ ds1 Here, the inner diameter side end face of the protrusion base 17f is the inner circumferential surface of the slinger 17 in this embodiment. In other words, a configuration may be adopted in which only the thickness of the protrusion base 17f protrudes to the inner diameter side without providing a protrusion. In this case, the protrusion is constituted only by the protrusion base 17f.

[0044] 4, protrusion base 17f covers the inner end surface of fitting portion 17a of slinger 17 and forms pressing portion 17g. Pressing portion 17g is formed by winding an elastic member extending from the inner end portion of protrusion base 17f toward the outer diameter side, around the inner end surface of fitting portion 17a of slinger 17. This makes it possible to prevent the elastic member from peeling off from the slinger when slinger 17 is pressed into place.

[0045] When the fitting portion 17a is fitted onto the fitting surface 3e of the hub wheel 3, the protrusion 17e fits into a recess 3j provided on the fitting surface 3e, thereby suppressing axial movement of the slinger 17 by the fitting force.

[0046] Next, a description will be given of the arrangement of the projection 17e and the fitting surface 3e of the hub wheel 3. With reference to Figures 4 and 5, a description will be given of the arrangement when a recess 3j is formed on the fitting surface 3e.

[0047] As shown in Figures 4 and 5, when the slinger 17 is fitted to the fitting surface 3e of the hub wheel 3, the protrusion 17e of the slinger 17 fits into the recess 3j. That is, the inner diameter side end of the protrusion 17e is fitted into the recess 3j while contacting the recess 3j. This seals the annular space S. For example, even if a gap is created between the fitting surface 3e of the hub wheel 3 and the fitting portion 17a of the slinger 17 when a load is applied, the protrusion 17e formed of an elastic member elastically deforms within the recess 3j and follows the gap, thereby preventing muddy water and the like from entering the annular space S.

[0048] As shown in FIG. 5, the protrusion 17e is a portion that protrudes toward the inner diameter side to fit into the recess 3j. The inner diameter ds1 of the end face on the inner diameter side of the protrusion 17e and the outer diameter dh2 of the inner side end portion 3i are dh2>ds1 Satisfy the relationship. With this configuration, even if the slinger 17 moves in the axial direction, the sealing properties of the protrusion 17e, which is an elastic member, are exhibited, making it possible to prevent the intrusion of muddy water and the like into the annular space S. Furthermore, even if the slinger 17 attempts to move toward the inner side, the protrusion 17e gets caught on the inner-side end portion 3i, making it possible to suppress the movement of the slinger 17. Even if the slinger 17 moves slightly toward the axial inner side while the protrusion 17e is elastically deforming within the recess 3j, forming a small gap between the hub wheel 3 and the slinger 17, the sealing properties of the protrusion 17e can suppress the intrusion of muddy water into the inside of the bearing.

[0049] As shown in FIG. 2B, in the case where a recess is not provided in the axial midway portion of the fitting surface 3e, the outer diameter dh2 of the inner end portion 3i, the inner diameter ds1 of the end face on the inner diameter side of the protrusion portion 17e, and the inner diameter ds2 of the end face on the inner diameter side of the protrusion base portion 17f are dh2>(ds1,ds2) Satisfy the relationship. With this configuration, the axial movement of the slinger 17 can be restricted by the fitting force between the fitting surface 3e of the hub wheel 3 and the protrusion 17e and / or the protrusion base 17f.

[0050] 4, when protrusion 17e is fitted into recess 3j, a gap A2 is formed between recess 3j and protrusion 17e. Even if fitting portion 17a of slinger 17 is scraped off by fitting surface 3e of the hub wheel when slinger 17 is pressed in, generating foreign matter such as burrs, the foreign matter remains in gap A2, thereby preventing the foreign matter from entering the annular space.

[0051] Furthermore, the inner diameter ds1 of the end surface on the inner diameter side of the protrusion 17e and the outer diameter dh3 of the end surface on the outer diameter side of the recess 3j shown in FIG. dh3>ds1 As a result, the inner diameter side end face of the protrusion 17e comes into contact with the outer circumferential surface of the recess 3j while being crushed, improving the fitting force. The outer diameter side end face of the recess 3j is the part that is most recessed (has the smallest diameter).

[0052] Next, the process of press-fitting the slinger 17 into the hub wheel 3 will be described with reference to FIG. As shown in FIG. 6(A), the slinger 17 penetrates into the hub wheel from the axially inner side. At this time, as shown in FIG. 6(A), pressure is applied to the pressing portion 17g of the protrusion base 17f. The provision of the pressing portion 17g makes it easier to apply pressure to the inner side end face of the slinger 17, improving the press-fitting property. In addition, since the outer diameter dh2 of the inner side end portion 3i is configured to be smaller than the outer diameter dh1 of the outer side portion 3h, the slinger 17 can be press-fitted while suppressing resistance during fitting. However, if the axial thickness of the pressing portion 17g is too thick, deformation of the pressing portion 17g increases when the slinger is pressed in, reducing the press-fitting property. Therefore, it is preferable to make the axial thickness of the pressing portion 17g thinner than the radial thickness of the protrusion base 17f.

[0053] 6(B), when the slinger 17 is pressed in, the projection 17e comes into contact with the inner end 3i while the fitting portion 17a of the slinger 17 comes into contact with the fitting surface 3e of the hub wheel. The projection 17e generates elastic deformation, overcomes the inner end 3i, and fits into the recess 3j. As shown in FIG. 6(C), when the protrusion 17e is fitted into the recess 3j, the outer diameter dh3 of the outer diameter side end of the recess 3j is larger than the inner diameter ds1 of the inner diameter side end face of the protrusion 17e, so that the inner diameter side end face of the protrusion 17e comes into contact with the outer peripheral surface of the recess 3j while being crushed, thereby improving the fitting force.

[0054] 7, the recess 3j has tapered surfaces 3j1, 3j2 on a surface continuing with the inner end 3i and a surface continuing with the outer portion 3h. The tapered surface 3j1 on the axially inner side continues with the inner end 3i, and the tapered surface 3j2 on the axially outer side continues with the outer portion 3h.

[0055] The taper angle θ1 of the tapered surface on the inside of the axial direction is 0°≦θ1≦90° The taper angle θ1 of 0° corresponds to the case where the recess 3j is not provided and the inclined portion 3k is provided, and the taper angle of 90° corresponds to the case where the side surface and the bottom surface of the recess 3j are perpendicular to each other without a tapered surface.

[0056] With this configuration, the tapered surface 3j1 is formed, so that the protrusion 17e of the slinger 17 can easily fit into the recess 3j when pressed in. The taper angle θ1 is preferably 45° or more. By setting the taper angle θ1 to 45° or more, when the slinger 17 moves toward the inner side, the protrusion 17e can easily come into contact with the tapered surface 3j1, and the effect of preventing the slinger 17 from coming out can be fully achieved.

[0057] In addition, the taper angle θ2 of the tapered surface on the axial outer side (outer side) is 0°<θ2≦90° The taper angle of 90° corresponds to a case where there is no tapered surface and the side surface and bottom surface of the recess 3j are perpendicular to each other. With this configuration, even if excessive force is applied during press-fitting, it is possible to prevent the protrusion 17e from being broken by the recess 3j. The taper angle θ2 is preferably 45° or less. By setting the taper angle θ2 to 45° or less, in the event that the slinger 17 moves toward the outer side, the shear force applied when the protrusion 17e abuts against the taper is reduced, and the effect of preventing breakage is easily exerted sufficiently.

[0058] In the second embodiment, as shown in Fig. 8(B), a configuration may be adopted in which no step is provided on the inner end surface of the slinger 17. By not providing a step, the number of processing steps is reduced, making processing easier. Also, it becomes easier to apply pressure to the inner end surface, improving press-fitting properties.

[0059] 9, an outer disk portion 17j may be provided by extending the plate surface portion of the slinger 17 further in the radial direction. The outer disk portion 17j is disposed on the inner side of the disk portion 17c, and is formed so that a portion of the outer disk portion 17j overlaps with the outer end portion of the outer member in the axial direction. This allows an additional labyrinth shape to be provided by the slinger 17. The joining portion between the radially inner end portion of the outer disk portion 17j and the disk portion 17c, and the bonding portion with the inner side surface of the wheel mounting flange 3b, are in close contact with each other via an elastic member 21.

[0060] The elastic member 21 is made of synthetic rubber such as NBR and prevents foreign matter from entering between the wheel mounting flange 3b and the disc portion 17c of the slinger 17, and can prevent rusting of the mounting portion of the slinger 17 for a long period of time.

[0061] Incidentally, while the wheel bearing device configured as a double row angular contact ball bearing using balls as the rolling elements 5 has been exemplified here, the present invention is not limited to this, and may also be a double row tapered roller bearing using tapered rollers as the rolling elements 5. Furthermore, as long as the wheel bearing device according to the present invention is of the inner ring rotation type, other than the exemplified third generation structure, it may also be, for example, a so-called second generation structure in which a pair of inner rings are press-fitted into the small diameter step of the hub ring, or a fourth generation structure in which inner rolling surfaces are formed directly on the outer peripheries of the hub ring and the outer joint member of the constant velocity universal joint.

[0062] The fourth-generation structure is provided with a CVJ outer joint member 61 having a raceway surface on its outer diameter. As shown in Fig. 10, a raceway surface 62 that faces the outer raceway surface 2a is formed on the outer diameter of the outer joint member 61. The outer joint member 61 is made up of a stem portion 63 and a mouth portion 64, and the raceway surface 62 is provided on the outer diameter of the outer end portion of the mouth portion 64. The outer peripheral surface of the stem portion 63 and the inner diameter of the hub wheel 3 are fixed to each other by spline fitting so as not to rotate.

[0063] Although the embodiments of the present invention have been described above, the present invention is not limited to these embodiments, which are merely illustrative, and it goes without saying that the present invention can be embodied in various other forms without departing from the gist of the present invention. The scope of the present invention is indicated by the claims, and further includes the equivalent meanings set forth in the claims, and all modifications within the scope of the claims. [Explanation of symbols]

[0064] 1 Wheel bearing device 2 Outer ring (outer component) 2a Outer raceway surface 3 Hub wheel 3a Small diameter stepped section 3b Wheel mounting flange 3d inner raceway surface 3e Mating surface 3h Outer side part 3i Inner end 3j Recess 3j1 Tapered surface 3j2 Tapered surface 4. Inner Circle 4a Inner raceway surface 5 Rolling elements 6 Inner seal material 7 Outer seal material 11 Slinger 12 Seal plate 13 Core wire 14 Seal part 15 Core wire 16 Seal part 17 Slinger 17a Mating part 17b Bend part 17c Disc section 17e Protrusion 17f protrusion base 17g Pressing part 17h Step 17j Outer disc part 21 Elastic member 51 Cage

Claims

1. an outer member having a double row outer raceway surface on an inner periphery thereof; an inner member including a hub wheel having, on its outer periphery, one inner raceway surface facing the outer raceway surface and a wheel mounting flange for mounting a wheel; and a raceway surface forming member connected to the hub wheel and having, on its outer periphery, the other inner raceway surface facing the outer raceway surface; a double row of rolling elements rollably accommodated between the raceway surfaces of the outer member and the inner member; a seal member that seals between the outer member and the inner member; A wheel bearing device comprising: The seal member is an outer seal member and has an annular slinger that fits around the hub wheel. A protrusion is provided on an inner end of a fitting surface of the slinger with the hub wheel, The protrusion is formed of an elastic material. A wheel bearing device comprising:

2. The outer diameter dh1 of the outer side portion of the fitting surface of the outer side seal member of the hub wheel and the outer diameter dh2 of the inner side end portion are dh1>dh2 2. The wheel bearing device according to claim 1, wherein the following relationship is satisfied:

3. a recess that fits onto the protrusion is provided on a fitting surface of the outer seal member of the hub wheel; The outer diameter dh2 of the inner end of the fitting surface of the outer seal member and the outer diameter dh3 of the recess are dh2>dh3 2. The wheel bearing device according to claim 1, wherein the following relationship is satisfied:

4. An outer diameter dh2 of the inner end of the hub wheel; The inner diameter ds1 of the protrusion of the slinger dh2>ds1 3. The wheel bearing device according to claim 2, wherein the following relationship is satisfied:

5. The outer diameter dh3 of the recess; The inner diameter ds1 of the protrusion of the slinger dh3>ds1 4. The wheel bearing device according to claim 3, wherein the following relationship is satisfied:

6. An inner diameter ds1 of the protrusion of the slinger; The inner diameter ds2 of the inner peripheral surface of the slinger; ds2 ≧ ds1 2. The wheel bearing device according to claim 1, wherein the following relationship is satisfied:

7. The recess has tapered surfaces on the axial inner side and the axial outer side, The taper angle θ1 of the tapered surface on the axially inner side is 0°≦θ1≦90° 4. The wheel bearing device according to claim 3, wherein the following relationship is satisfied:

8. The taper angle θ2 of the tapered surface on the axially inner side is 0°<θ2≦90° 8. The wheel support bearing device according to claim 7, wherein the following relationship is satisfied:

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