JP2015183801A - wheel bearing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wheel bearing device which includes a seal with improved seal performance and consequently can maintain bearing performance for a long period of time.SOLUTION: A metal ring 12 comprises: a fitting part 12a which externally fits onto a shoulder part 4e of a hub ring 4; a curved part 12b formed into a circular shape; a disc part 12c which extends radially outward, and is brought into close contact with a side surface 6c of a wheel mounting flange 6; and a bent part 12d which separates from the outside diameter part of the disc part 12c with respect to the side surface 6c, and extends radially outward. A synthetic rubber-made circular deflector member 15 is joined to the bent part 12d by vulcanization adhesion, and the deflector member 15 comprises a bevel part 16 having: an outside diameter surface 16a which covers an external peripheral face 2c of a cylindrical end part of an outer member 2, and is formed into a tapered shape so as to gradually diametrically reduce toward an inner side from a base part 15a of the deflector member 15; and an inside diameter part 16b which is formed into a cylindrical surface. A labyrinth clearance δ is formed between the inside diameter surface 16b and the external peripheral face 2c of the outer member 2.

Description

  The present invention relates to a wheel bearing device for rotatably supporting a wheel of an automobile or the like, and more particularly to a wheel bearing device with improved sealing performance.

  2. Description of the Related Art Conventionally, a wheel bearing device for supporting a wheel of an automobile or the like is such that a hub wheel for mounting a wheel is rotatably supported via a rolling bearing, and there are a drive wheel and a driven wheel. For structural reasons, an inner ring rotation method is generally used for driving wheels, and an inner ring rotation method and an outer ring rotation method are generally used for driven wheels. As the wheel bearing device, a double-row angular ball bearing having a desired bearing rigidity, exhibiting durability against misalignment, and having a small rotational torque from the viewpoint of improving fuel efficiency is often used. On the other hand, double row tapered roller bearings are used in vehicles such as off-road cars and trucks that have a heavy vehicle body weight.

  Since this type of wheel bearing device is disposed at a site where muddy water or the like is likely to be applied, a seal device is mounted to seal between the outer member and the inner member. Generally, in a sealing device, a sealing member having a sealing lip is attached to an outer member serving as a stationary member, and the sealing lip is slidably contacted with an outer peripheral surface of the inner member.

  An example of such a wheel bearing device is shown in FIG. The wheel bearing device 50 includes an outer member 51 that is non-rotatably attached to the vehicle body side, and an inner member 52 that is rotatably supported by the outer member 51 via a ball 60. ) Is fixed to the inner member 52 and is rotatable with respect to the vehicle body. And since the wheel bearing apparatus 50 is arrange | positioned in the place where muddy water etc. are easy to apply, it is comprised so that the sealing device may be arrange | positioned and the space between the inner member 52 and the outer member 51 may be sealed.

  This sealing device includes a seal 53 fitted to the inner periphery of the end of the outer member 51 and a metal ring 57 fitted to the base 56 of the wheel mounting flange 55 of the hub wheel 54. The seal 53 includes a seal member 58 made of an elastic member such as an annular synthetic rubber, and a core metal 59 that holds the seal member 58. The seal member 58 has a pair of side lips 58a, 58b and a grease lip 58c, and the lips 58a, 58b, 58c are arranged so as to be in sliding contact with the metal ring 57, respectively.

  The metal ring 57 includes a cylindrical fitting portion 57a that is fitted on the shoulder portion 54a of the hub wheel 54, a curved portion 57b that is formed in an arc shape corresponding to the base portion 56 that is formed in an arc shape, A disc portion 57c that extends radially outward from the curved portion 57b and is in close contact with the side surface 55a of the wheel mounting flange 55, and is spaced apart from the outer diameter portion of the disc portion 57c in the axial direction with respect to the wheel mounting flange 55. And an umbrella portion 57d that extends and a bent portion 57e that protrudes radially outward from the umbrella portion 57d.

  The base portion 56 is formed in a circular arc surface having a predetermined radius of curvature r at a corner portion between the shoulder portion 54 a of the hub wheel 54 and the wheel mounting flange 55. Corresponding to the arc surface, the curved portion 57b of the metal ring 57 is formed of an arc surface having a predetermined radius of curvature R, and the respective curvature radii R and r are set such that R ≧ r. Thereby, when the metal ring 57 is fitted to the base portion 56, the curved portion 57b of the metal ring 57 is prevented from interfering with the arc surface of the base portion 56 and rising. Therefore, a gap is prevented from being generated between the side surface 55a of the wheel mounting flange 55 and the disc portion 57c of the metal ring 57, and the both are brought into close contact with each other, and stable sealing is achieved by suppressing variations in the side lips 58a and 58b. Sex can be secured.

  Further, a tapered surface 51 a having a predetermined inclination angle θ <b> 1 is formed on the outer periphery of the end portion of the outer member 51. On the other hand, the umbrella portion 57d of the metal ring 57 has a predetermined inclination angle θ2 corresponding to the tapered surface 51a of the outer member 51, and is formed in a tapered shape that gradually increases in diameter toward the end portion. And the cyclic | annular clearance gap A is formed between the taper surfaces 51a, and the labyrinth seal is comprised. The inclination angles θ1 and θ2 are set in a range of 15 ° to 30 ° so as to be the same angle, and the gap A is set in a range of 0.05 to 1.0 mm (diameter).

  Thus, the labyrinth effect formed by the inner peripheral surface of the umbrella portion 57d and the tapered surface 51a of the outer member 51 prevents muddy water or the like from entering the sliding contact portion between the seal 53 and the metal ring 57. In addition, even if muddy water or the like enters the inside of the metal ring 57 from this gap A, it is easily discharged to the outside by the centrifugal force accompanying the rotation of the metal ring 57 as shown by the arrows in the figure. It does not stay on the lip 58a. Therefore, muddy water or the like can be prevented from adhering to the sliding contact surface of the side lip 58a and worn, and a stable sealing performance can be maintained over a long period of time (see, for example, Patent Document 1).

JP 2010-32013 A

  In such a conventional sealing device for the wheel bearing device 50, the labyrinth effect formed by the inner peripheral surface of the umbrella portion 57 d of the metal ring 57 and the tapered surface 51 a of the outer member 51, the seal 53 and the metal ring 57 are separated. It has a feature that can prevent muddy water or the like from entering the sliding contact portion. Here, the labyrinth gap A between the metal ring 57 and the tapered surface 51a of the outer member 51 can be further reduced to further improve the muddy water resistance. However, since the labyrinth seal is made of metal made of the metal ring 57 and the outer member 51 formed by pressing, there is variation in manufacturing dimensions, and the labyrinth gap A is set to be narrow. There is a limit. Further, since the metal ring 57 is fixed to the hub ring 54 serving as a rotating member, the rotation of the hub ring 54 causes the umbrella portion 57d of the metal ring 57 to swell due to centrifugal force, and the labyrinth gap A becomes larger during operation. It is difficult to maintain a stable sealing property over a long period of time.

  The present invention has been made in view of such circumstances, conceived of a deflector seal that can minimize the influence of the centrifugal force of the metal ring, and can set the labyrinth gap with the outer member more narrowly. An object of the present invention is to provide a wheel bearing device capable of improving the performance and maintaining the bearing performance over a long period of time.

  In order to achieve such an object, the invention according to claim 1 of the present invention has a vehicle body mounting flange integrally attached to the suspension on the outer periphery, and a double row outer rolling surface integrally on the inner periphery. The formed outer member, a wheel mounting flange for mounting the wheel at one end, and an inner rolling surface facing one of the double-row outer rolling surfaces on the outer periphery, and the inner rolling A hub ring formed with a small-diameter step portion extending in the axial direction from the surface, and an inner ring fitted to the hub ring and having an inner rolling surface facing the other of the outer rolling surfaces of the double row on the outer periphery, or An inner member composed of an outer joint member of a constant velocity universal joint, a double row rolling element accommodated between both rolling surfaces of the inner member and the outer member, and the outer member A seal mounted on both side openings of the annular space formed between the inner member and the inner member. The seal on the outer side of the seal is composed of a core metal fitted to the inner periphery of the end of the outer member, and a seal member integrally joined to the core metal, and the base on the inner side of the wheel mounting flange Is formed in a circular arc shape in cross section, a metal ring is fitted to the base, and the seal member is slidably contacted with the metal ring, the metal ring is fitted on the shoulder of the hub ring. A cylindrical fitting portion that is formed, a curved portion that is formed in a cross-section arc shape corresponding to the base portion that is formed in a cross-section arc shape, and extends radially outward from the curved portion, An annular deflector member made of synthetic rubber is joined to the metal ring, and the deflector member extends to the inner side from the joined portion, and Outside the outer edge of the member It includes a valve head that covers the surface, a labyrinth seal is formed between an outer peripheral surface of the outer member and the umbrella portion.

  Thus, the outer side seal is composed of a core metal fitted to the inner periphery of the end of the outer member, and a seal member integrally joined to the core metal, and the base part on the inner side of the wheel mounting flange is In a third or fourth generation wheel bearing device having a circular arc cross section, a metal ring fitted to the base, and a seal member in sliding contact with the metal ring, the metal ring is a shoulder of the hub ring. A cylindrical fitting portion that is externally fitted to the portion, a curved portion that is formed in an arc shape corresponding to the base portion that is formed in an arc shape in cross section, and a wheel mounting that extends radially outward from the curved portion. An annular deflector member made of synthetic rubber and joined to the metal ring, and the deflector member extends to the inner side from the joint portion, and is an outer member. An umbrella part covering the outer peripheral surface of the outer end of the Since the labyrinth seal is formed between the outer surface of the umbrella portion and the outer member, it is possible to prevent the muddy water or the like from entering the sliding contact portion between the seal and the metal ring. In addition, the labyrinth seal is not made of metal composed of a metal ring and an outer member formed by press working as in the prior art, but the deflector member is vulcanized and molded into a metal ring with synthetic rubber. Therefore, variations in manufacturing dimensions can be suppressed, the labyrinth gap can be set narrow, and, for example, the outer member is tilted or the outer peripheral surface is deformed when the vehicle turns, and the umbrella portion comes into contact with the umbrella portion. However, there is no fear that the outer member and the deflector member are damaged only by the elastic deformation of the umbrella portion. Accordingly, it is possible to provide a wheel bearing device capable of improving the sealing performance of the seal and maintaining the bearing performance over a long period of time.

  Preferably, if the umbrella part of the deflector member is formed in the shape of a spire as in the invention described in claim 2, the mass of the umbrella part decreases as the distance from the base part decreases, and the centrifugal force decreases. The influence can be minimized and the labyrinth gap can be prevented from expanding.

  If the annular groove is formed on the outer diameter surface of the umbrella portion of the deflector member as in the invention described in claim 3, the intrusion occurs between the side surface of the wheel mounting flange and the disk portion of the metal ring. Foreign matters such as muddy water to be flowed can be reduced by flowing into the lower portion through the annular groove, and rusting of the base portion and the mounting portion of the metal ring can be prevented.

  According to a fourth aspect of the present invention, an annular step is formed on the outer periphery of the outer side end of the outer member, and the deflector member extends from the base to the inner side, An umbrella portion covering the step portion of the side member, and an annular gap between the inner diameter surface of the umbrella portion and the step portion, and an axial direction between the tip portion of the umbrella portion and the wall surface of the step portion. If a gap is formed and an L-shaped labyrinth seal is formed, the labyrinth effect is further exerted by the L-shaped labyrinth seal formed by the umbrella portion and the stepped portion of the outer member. Can be improved.

  Moreover, if the base part of the said deflector member is formed thickly like invention of Claim 5, the rigidity of an umbrella part will become high and the influence of the centrifugal force accompanying rotation of a metal ring will be minimized. Can be suppressed.

  According to a sixth aspect of the present invention, the metal ring has a bent portion that extends radially outward from the outer diameter portion of the disc portion in an axial direction with respect to the wheel mounting flange. If the deflector member is integrally joined from the bent portion to the distal end portion, the tip end portion is inclined and extended radially outward from the bent portion. And the rigidity of the umbrella is increased, and the influence of centrifugal force accompanying the rotation of the metal ring can be minimized.

  According to a seventh aspect of the present invention, the deflector member includes an elastic lip that extends from the base portion to the outer side and has a triangular cross section, and the elastic lip is an inner side of the wheel mounting flange. If it is in elastic contact with the side surface of the metal ring, foreign matter can be prevented from entering between the side surface of the wheel mounting flange and the disk part of the metal ring, and rusting of the base part and the metal ring mounting part can occur over a long period of time. Can be prevented.

  Further, as in the invention according to claim 8, if the labyrinth gap between the umbrella portion of the deflector member and the outer peripheral surface of the outer member is set in a range of 0.2 to 1.0 mm (diameter). Further, due to dimensional variation or eccentricity of the umbrella part or the outer member, there is no possibility that the inner diameter surface of the umbrella part interferes with the outer member, and muddy water or the like can be effectively prevented from entering.

  A wheel bearing device according to the present invention has an outer member integrally formed with a vehicle body mounting flange for mounting to a suspension device on the outer periphery, and an outer member formed integrally with a double row outer rolling surface on the inner periphery, and one end A wheel mounting flange for mounting the wheel on the part, an inner rolling surface facing one of the outer rolling surfaces of the double row on the outer periphery, and a small diameter step portion extending in the axial direction from the inner rolling surface And an outer joint member of an inner ring or a constant velocity universal joint that is fitted to the hub ring and has an inner rolling surface facing the other of the outer rolling surfaces of the double row on the outer periphery. Formed between the outer member and the inner member, a double row rolling element housed between the rolling surfaces of the inner member and the outer member. And seals mounted on both side openings of the annular space. And a base member fitted to the inner periphery of the end portion of the outer member and a seal member integrally joined to the core member, and a base portion on the inner side of the wheel mounting flange has an arcuate cross section. In the wheel bearing device formed and fitted with a metal ring on the base, and the seal member is slidably contacted with the metal ring, the metal ring has a cylindrical shape fitted on the shoulder of the hub ring. A fitting portion, a curved portion formed in a cross-section arc shape corresponding to the base portion formed in a cross-section arc shape, and extending radially outward from the curved portion, on the side surface on the inner side of the wheel mounting flange An annular deflector member made of synthetic rubber is joined to the metal ring, and the deflector member extends to the inner side from the joined portion, and is attached to the outer side of the outer member. It has an umbrella part that covers the outer peripheral surface of the end part. Since part labyrinth seal between the outer peripheral surface of the outer member is formed, it is possible to prevent the muddy water or the like from entering the sliding contact portion between the seal and the metal ring. In addition, the labyrinth seal is not made of metal composed of a metal ring and an outer member formed by press working as in the prior art, but the deflector member is vulcanized and molded into a metal ring with synthetic rubber. Therefore, variations in manufacturing dimensions can be suppressed, the labyrinth gap can be set narrow, and, for example, the outer member is tilted or the outer peripheral surface is deformed when the vehicle turns, and the umbrella portion comes into contact with the umbrella portion. However, there is no fear that the outer member and the deflector member are damaged only by the elastic deformation of the umbrella portion. Accordingly, it is possible to provide a wheel bearing device capable of improving the sealing performance of the seal and maintaining the bearing performance over a long period of time.

It is a longitudinal section showing one embodiment of a wheel bearing device concerning the present invention. It is a principal part enlarged view which shows the seal part of FIG. The deformation | transformation state by the centrifugal force of the deflector member which concerns on this invention is shown, (a) is a schematic diagram which shows a comparative example, (b) is a schematic diagram which shows the deflector member of FIG. It is a principal part enlarged view which shows the modification of the deflector member of FIG. It is a principal part enlarged view which shows the modification of the deflector member of FIG. It is a principal part enlarged view which shows the other modification of the deflector member of FIG. It is a principal part enlarged view which shows the modification of the deflector member of FIG. It is a principal part enlarged view which shows the modification of the deflector member of FIG. It is a principal part enlarged view which shows the modification of the metal ring of FIG. It is a principal part enlarged view which shows the sealing device of the conventional wheel bearing apparatus.

  An outer member integrally having a vehicle body mounting flange to be attached to the suspension device on the outer periphery, a double row outer rolling surface formed integrally on the inner periphery, and a wheel mounting flange for attaching a wheel to one end And a hub wheel in which an inner rolling surface facing one of the double row outer rolling surfaces and a small-diameter step portion extending in the axial direction from the inner rolling surface are formed on the outer periphery, and the hub An inner member composed of an inner ring that is fitted to a ring and has an inner race surface on the outer periphery that faces the other of the outer rows of the double row, and both the inner member and the outer member. A plurality of rolling elements accommodated in a freely rolling manner between the surfaces, and seals mounted on both side openings of the annular space formed between the outer member and the inner member. Outer side seal is a metal core fitted to the inner periphery of the end of the outer member, and the metal core A base member on the inner side of the wheel mounting flange is formed in an arc shape in cross section, and a metal ring formed by pressing from a steel plate is fitted to the base part. In the wheel bearing device in which the side lip of the seal member is slidably contacted, the metal ring includes a cylindrical fitting portion that is fitted on a shoulder portion of the hub wheel, and the base portion that is formed in an arc shape. Corresponding to the curved portion, a disc portion extending radially outward from the curved portion and being in close contact with the inner side surface of the wheel mounting flange, and an outer diameter of the disc portion And a bent portion extending radially outward from the wheel mounting flange in the axial direction, and an annular deflector member made of synthetic rubber is integrally joined to the bent portion by vulcanization adhesion This deflector member is The outer surface of the outer member is covered with a cylindrical outer peripheral surface, and is formed on a cylindrical surface and an outer diameter surface formed in a tapered shape that gradually decreases in diameter from the base of the deflector member toward the inner side. An umbrella portion having an inner diameter surface is provided, and a labyrinth gap is formed between the inner diameter surface and the outer peripheral surface of the outer member.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
1 is a longitudinal sectional view showing an embodiment of a wheel bearing device according to the present invention, FIG. 2 is an enlarged view of a main part showing a seal portion of FIG. 1, and FIG. 3 is a centrifugal view of a deflector member according to the present invention. FIG. 4A is a schematic diagram showing a comparative example, FIG. 4B is a schematic diagram showing the deflector member of FIG. 2, and FIG. 4 is a main part showing a modified example of the deflector member of FIG. FIG. 5 is an enlarged view of a main part showing a modification of the deflector member in FIG. 4, FIG. 6 is an enlarged view of a main part showing another modification of the deflector member in FIG. 2, and FIG. FIG. 8 is a main part enlarged view showing a modification of the deflector member of FIG. 7, and FIG. 9 is a main part enlarged view showing a modification of the metal ring of FIG. is there. In the following description, the side closer to the outer side of the vehicle when assembled to the vehicle is referred to as the outer side (left side in FIG. 1), and the side closer to the center is referred to as the inner side (right side in FIG. 1).

  This wheel bearing device is for a drive wheel called a third generation, and is an outer member 1 and an outer member inserted on the inner member 1 via double-row rolling elements (balls) 3. And a member 2. The inner member 1 includes a hub ring 4 and an inner ring 5 fixed to the hub ring 4.

  The hub wheel 4 integrally has a wheel mounting flange 6 for mounting a wheel (not shown) at an end portion on the outer side, and has one (outer side) inner rolling surface 4a on the outer periphery and the inner rolling surface. A cylindrical small-diameter step portion 4b extending in the axial direction from the surface 4a is formed, and a serration (or spline) 4d for torque transmission is formed on the inner periphery. Hub bolts 6a are planted on the wheel mounting flange 6 at equal intervals in the circumferential direction.

  The inner ring 5 is formed with the other (inner side) inner rolling surface 5a on the outer periphery, and is press-fitted into the small-diameter step portion 4b of the hub wheel 4 through a predetermined shimiro, and the end portion of the small-diameter step portion 4b is radially outward. It is fixed to the hub wheel 4 in the axial direction in a state where a predetermined bearing preload is applied by a caulking portion 4c formed by plastic deformation in the direction.

  The hub wheel 4 is made of medium and high carbon steel containing 0.40 to 0.80 wt% of carbon such as S53C, and has a surface hardness by induction quenching from the base 6b on the inner side of the wheel mounting flange 6 to the small diameter step 4b. Is cured in the range of 58 to 64 HRC. The caulking portion 4c is an unquenched portion while maintaining the surface hardness after forging. This has sufficient mechanical strength against the rotational bending load applied to the wheel mounting flange 6, improves the fretting resistance of the small-diameter stepped portion 4b serving as the fitting portion of the inner ring 5, and performs caulking. It is possible to prevent micro cracks and the like from occurring in the crimped portion 4c due to processing.

  The outer member 2 integrally has a vehicle body mounting flange 2b to be attached to a knuckle (not shown) on the outer periphery, and faces the double row inner rolling surfaces 4a and 5a of the inner member 1 on the inner periphery. Double row outer rolling surfaces 2a, 2a are integrally formed. The outer member 2 is formed of medium-high carbon steel containing 0.40 to 0.80 wt% of carbon such as S53C, and at least the double row outer rolling surfaces 2a and 2a have a surface hardness of 58 to 64 HRC by induction hardening. Hardened to range.

  On the other hand, the inner ring 5 is made of high carbon chrome steel such as SUJ2, and is hardened in the range of 58 to 64 HRC up to the core part by quenching. Further, the rolling element 3 is made of high carbon chrome steel such as SUJ2, and is hardened in the range of 62 to 67 HRC up to the core by quenching. And the double row rolling elements 3 and 3 are accommodated between both rolling surfaces of the outer member 2 and the inner member 1, and are held by the cages 7 and 7 so as to roll freely. It constitutes a ball bearing.

  Further, seals 8 and 9 are attached to the opening of the annular space formed between the outer member 2 and the inner member 1. These seals 8 and 9 prevent the grease sealed inside the bearing from leaking outside and preventing rainwater, dust, and the like from entering the bearing from the outside. The inner side seal 9 constitutes a so-called pack seal composed of an annular seal plate 10 and a slinger 11 which are opposed to each other with an L-shaped cross section.

  In the present embodiment, the metal ring 12 is fitted to the inner side base portion 6 b of the wheel mounting flange 6, and the outer side seal 8 is disposed so as to be in sliding contact with the metal ring 12. Specifically, as shown in an enlarged view in FIG. 2, the seal 8 includes a metal core 13 fitted to the inner periphery of the outer side end of the outer member 2, and vulcanization adhesion or the like to the metal core 13. The seal member 14 is integrally joined. The core metal 13 is formed in a U-shaped section by cold pressing from a cold-rolled steel sheet (such as JIS standard SPCC system) because the metal ring 12 is not subjected to muddy water, but has a rust-proof austenitic stainless steel. A steel plate (JIS standard SUS304 or the like) may be used.

  On the other hand, the seal member 14 is made of synthetic rubber such as NBR (acrylonitrile-butadiene rubber), and is joined to the outer peripheral portion of the core metal 13 and extends sideward lip 14a and dust lip 14b extending in a radially outward direction, and the core metal. 13 has a grease lip 14c which is joined to the inner edge of the bearing 13 and extends incliningly toward the bearing inner side. The side lip 14a, the dust lip 14b, and the grease lip 14c are in sliding contact with the metal ring 12 fitted to the base 6b on the inner side of the wheel mounting flange 6. A seal member 14 is wrapped around and joined to the outer portion of the cored bar 13 to form a so-called half metal structure. Thereby, the airtightness of the fitting part between the outer member 2 and the cored bar 13 is improved, and foreign matter such as muddy water is prevented from entering the bearing.

  As the material of the seal member 14, in addition to the exemplified NBR, for example, HNBR (hydrogenated acrylonitrile butadiene rubber), EPDM (ethylene propylene rubber), etc. having excellent heat resistance, heat resistance, chemical resistance, etc. Examples thereof include ACM (polyacrylic rubber), FKM (fluororubber), and silicon rubber, which are excellent in the above.

  The metal ring 12 is formed by pressing from a corrosion-resistant steel plate, for example, an austenitic stainless steel plate, a ferritic stainless steel plate (JIS standard SUS430 series, etc.), or a rust-proof cold-rolled steel plate. A cylindrical fitting portion 12a fitted on the shoulder portion 4e of the ring 4, a curved portion 12b formed in an arc shape corresponding to the base portion 6b formed in an arc shape, and a radial direction from the curved portion 12b A disk portion 12c that extends outward and is in close contact with the inner side surface 6c of the wheel mounting flange 6, and is radially separated from the wheel mounting flange 6 in the axial direction from the outer diameter portion of the disk portion 12c. A bending portion 12d extending outward. The bent portion 12d is a portion where a later-described deflector member 15 is joined, and the rigidity of the metal ring 12 can be improved and the size and shape accuracy of the metal ring 12 can be increased.

  In addition, as for this metal ring 12, the surface roughness of the steel plate used as a raw material is set to the range of Ra0.2-0.6. Thereby, a favorable seal sliding contact surface can be obtained, lip wear can be suppressed, and the sealing performance of the seal 8 can be maintained even when used in a poor environment. Note that Ra is one of JIS roughness shape parameters (JIS B0601-1994), and is an arithmetic average roughness, which means an average value of absolute value deviations from an average line.

  The base portion 6 b is formed in a cross-sectional arc surface having a predetermined radius of curvature r at a corner portion between the shoulder portion 4 e of the hub wheel 4 and the wheel mounting flange 6. Corresponding to the arc surface, the curved portion 12b of the metal ring 12 is formed of an arc surface having a predetermined radius of curvature R, and the respective curvature radii R and r are set such that R ≧ r. Thereby, when the metal ring 12 is fitted to the base portion 6b, the curved portion 12b of the metal ring 12 is prevented from interfering with the arc surface of the base portion 6b and rising.

  An annular deflector member 15 is integrally joined to the bent portion 12d of the metal ring 12 by vulcanization adhesion. The deflector member 15 is made of a synthetic rubber such as NBR, and extends from the base (joining portion) 15a to the outer side, and has an elastic lip 15b having a triangular cross section, and extends from the base 15a to the inner side. The umbrella part 16 which covers the cylindrical outer peripheral surface 2c of the edge part of the outer side is provided. The elastic lip 15b is elastically brought into contact with the side surface 6c of the wheel mounting flange 6 to prevent foreign matter from entering from between the side surface 6c of the wheel mounting flange 6 and the disk portion 12c of the metal ring 12, and the base portion 6b and the metal ring. The rusting of the 12 mounting portions can be prevented over a long period of time.

  The umbrella section 16 has a spire-shaped cross section, and includes an outer diameter surface 16a formed in a tapered shape that gradually decreases in diameter toward the inner side, and an inner diameter surface 16b formed in a cylindrical surface. An annular labyrinth gap δ is formed between the inner diameter surface 16b and the cylindrical outer peripheral surface 2c of the outer member 2, thereby forming a labyrinth seal. The labyrinth gap δ is set in a range of 0.2 to 1.0 mm (diameter). When the labyrinth gap δ is less than 0.2 mm, the inner diameter surface 16b of the umbrella portion 16 may interfere with the outer member 2 due to dimensional variation or eccentricity of the umbrella portion 16 or the outer member 2, and If it exceeds 0 mm, it is not preferable because muddy water or the like easily enters.

  As described above, the labyrinth effect formed by the inner diameter surface 16 b of the umbrella portion 16 and the outer peripheral surface 2 c of the outer member 2 prevents muddy water or the like from entering the sliding contact portion between the seal 8 and the metal ring 12. be able to. In addition, the labyrinth seal is not composed of metals that are formed by press working and an outer member as in the prior art, but the deflector member 15 is vulcanized to the metal ring 12 with synthetic rubber. Since it is molded, variations in manufacturing dimensions can be suppressed, the labyrinth gap δ can be set narrow, and, for example, the outer member 2 is tilted or the outer peripheral surface 2c is deformed when the vehicle turns. Even if it comes into contact with the umbrella part 16, the outer part 2 and the deflector member 15 are not damaged only by the elastic deformation of the umbrella part 16. Therefore, it is possible to provide a wheel bearing device capable of improving the sealing performance of the seal 8 and maintaining the bearing performance over a long period of time.

  Furthermore, in this embodiment, since the outer diameter surface 16a of the umbrella portion 16 of the deflector member 15 is formed in a tapered shape that gradually decreases in diameter toward the inner side, the influence of centrifugal force accompanying the rotation of the metal ring 12 is reduced. Can be minimized. That is, as schematically shown in FIG. 3 (a), when the umbrella portion 16 has a cylindrical shape with a constant thickness, the rotation by the centrifugal force (F1 = F2 = F3) during rotation increases as the distance from the base portion 15a increases. The moment around the axis P increases and swells and expands as shown by the broken line in the figure, and the labyrinth gap δ expands and mud water and the like easily enter, but this embodiment shown in FIG. Thus, if the umbrella part 16 is formed in a spire shape, the mass of the umbrella part 16 decreases as the distance from the base part 15a decreases, and the centrifugal force (F1> F2> F3) decreases to minimize the influence. The labyrinth gap δ can be prevented from expanding.

  In addition, although the 3rd generation structure by the side of a driven wheel was illustrated here as a wheel bearing apparatus, the wheel bearing apparatus which concerns on this invention is not limited to this, If it is an applicable structure, it is 4th generation. Also good. Furthermore, in the present embodiment, an example of a double-row angular contact ball bearing using balls as the rolling elements 3 is illustrated, but it is not limited to this, and a double-row tapered roller bearing using tapered rollers as the rolling elements is used. It may be configured.

  FIG. 4 shows a modification of the deflector member. This embodiment is basically the same as that of the above-described embodiment (FIG. 2) except that the shapes of the seal 8 and the umbrella portion 16 of the deflector member 15 and the outer member 2 are different. The parts and parts having the same reference numerals are given the same reference numerals, and detailed description thereof is omitted.

  Similar to the embodiment described above, the metal ring 12 is fitted to the inner side base 6 b of the wheel mounting flange 6, and the outer side seal 17 is disposed so as to be in sliding contact with the metal ring 12. The deflector member 18 is integrally joined to the bent portion 12d of the metal ring 12 by vulcanization adhesion.

  The seal 17 includes a cored bar 20 that is fitted to the inner periphery of the outer side end of the outer member 19 and a seal member 21 that is integrally joined to the cored bar 20 by vulcanization adhesion or the like. The core metal 20 is formed in a U-shaped cross section by press working from a cold rolled steel sheet. On the other hand, the seal member 21 is made of a synthetic rubber such as NBR, and is joined to the outer peripheral portion of the core metal 20 and joined to the pair of side lips 21a and 21b extending obliquely outward in the radial direction and the inner edge of the core metal 20. And has a grease lip 21c extending inclinedly toward the inner side of the bearing. These side lips 21 a and 21 b and the grease lip 21 c are in sliding contact with the metal ring 12 fitted to the base portion 6 b on the inner side of the wheel mounting flange 6. A seal member 21 is wrapped around and joined to the outer portion of the cored bar 20 to form a half metal structure.

  A tapered surface 19a having a predetermined inclination angle β1 is formed on the outer periphery of the outer end of the outer member 19. The deflector member 18 is made of synthetic rubber such as NBR, extends from the base portion 15a to the outer side, has an elastic lip 15b having a triangular cross section, extends from the base portion 15a to the inner side, and has a tapered surface 19a of the outer member 19 The umbrella part 22 to cover is provided. The umbrella portion 22 is formed in a spire shape in cross section, and includes an outer diameter surface 22a formed on a cylindrical surface, and an inner diameter surface 22b formed in a tapered shape that gradually increases in diameter toward the inner side. The inner diameter surface 22b is provided with a predetermined inclination angle β2 corresponding to the tapered surface 19a of the outer member 19, and an annular labyrinth gap δ is formed between the inner surface 22b and the tapered surface 19a to constitute a labyrinth seal. .

  As described above, the labyrinth effect formed by the inner diameter surface 22 b of the umbrella portion 22 and the tapered surface 19 a of the outer member 19 prevents muddy water from entering the sliding contact portion between the seal 17 and the metal ring 12. In addition, since the deflector member 18 is formed by vulcanization molding of the metal ring 12 with synthetic rubber, variations in manufacturing dimensions can be suppressed, and the labyrinth gap δ can be set narrow. Further, even if muddy water or the like enters the inside of the metal ring 12 from the labyrinth gap δ, it is easily discharged to the outside by the centrifugal force accompanying the rotation of the metal ring 12 as shown by the arrow in the figure, and on the side lip 21a. It will not stay in. Therefore, muddy water or the like can be prevented from adhering to the sliding contact surface of the side lip 21a and worn, and a stable sealing performance can be maintained over a long period of time.

  The inclination angles β1 and β2 are set in a range of 15 ° to 30 ° so as to be substantially the same angle. If the inclination angles β1 and β2 exceed 30 °, mud water or the like easily enters, and if it is less than 15 °, mud water or the like that has entered through the labyrinth seal becomes difficult to drain by centrifugal force, which is not preferable. The abbreviation “substantially the same” as used herein means, for example, a design target value that is substantially free from an angular difference, that is, an angular difference caused by a processing error or the like should be allowed. .

  Furthermore, since the inner diameter surface 22b of the umbrella portion 22 is formed in a tapered shape that gradually increases in diameter toward the inner side, the influence of centrifugal force accompanying the rotation of the metal ring 12 is minimized as in the above-described embodiment. Can be suppressed.

  Next, other modified examples of the deflector member are shown in FIGS. The embodiment shown in FIG. 5 basically differs from the above-described embodiment (FIG. 4) only in that the shape of the umbrella portion 22 of the deflector member 18 is different. Parts are denoted by the same reference numerals and detailed description thereof is omitted.

  Similar to the embodiment described above, the metal ring 12 is fitted to the inner side base 6 b of the wheel mounting flange 6, and the outer side seal 17 is disposed so as to be in sliding contact with the metal ring 12. The deflector member 23 is integrally joined to the bent portion 12d of the metal ring 12 by vulcanization adhesion.

  The deflector member 23 is made of synthetic rubber such as NBR, extends from the base portion 15a to the outer side, has an elastic lip 15b having a triangular cross section, extends from the base portion 15a to the inner side, and the tapered surface 19a of the outer member 19 A covering umbrella portion 24 is provided. The umbrella portion 24 is formed in a spire-like cross section, and includes an outer diameter surface 24a in which an annular groove 25 having an arc-shaped cross section is formed, and an inner diameter surface 22b formed in a tapered shape that gradually increases in diameter toward the inner side. ing.

  As described above, in this embodiment, the sliding between the seal 17 and the metal ring 12 is performed by the labyrinth effect formed by the inner diameter surface 22b of the umbrella portion 24 and the tapered surface 19a of the outer member 19 as in the above-described embodiment. It is possible to prevent intrusion of muddy water or the like into the contact portion, and since the deflector member 23 is vulcanized and molded to the metal ring 12 with synthetic rubber, it is possible to suppress variations in manufacturing dimensions and to reduce the labyrinth gap δ. Since the inner diameter surface 22b of the umbrella portion 24 is formed in a tapered shape that gradually increases in diameter toward the inner side, the influence of centrifugal force associated with the rotation of the metal ring 12 is minimized. Can be suppressed. Furthermore, since the annular groove 25 is formed in the outer diameter surface 24a of the umbrella portion 24, foreign matter such as muddy water that is about to enter between the side surface 6c of the wheel mounting flange 6 and the disc portion 12c of the metal ring 12 is removed. This annular groove 25 can be reduced by flowing into the lower portion (road surface side), thereby preventing rusting of the base 6b and the mounting portion of the metal ring 12.

  The embodiment shown in FIG. 6 is basically the same part or the same part other than the umbrella member 16 and the outer member 2 of the deflector member 15 of the above-described embodiment (FIG. 2). Parts and parts having functions are denoted by the same reference numerals, and detailed description thereof is omitted.

  Similar to the above-described embodiment, the metal ring 12 is fitted to the inner side base portion 6 b of the wheel mounting flange 6, and the outer side seal 8 is disposed so as to be in sliding contact with the metal ring 12. The deflector member 26 is integrally joined to the bent portion 12d of the metal ring 12 by vulcanization adhesion.

  An annular step portion 28 is formed on the outer periphery of the outer end portion of the outer member 27. The deflector member 26 is made of synthetic rubber such as NBR, and extends from the base portion 15a to the outer side, and has an elastic lip 15b having a triangular cross section, and extends from the base portion 15a to the inner side. Umbrella part 29 which covers 28 is provided. The umbrella part 29 includes an outer diameter surface 29a in which an annular groove 25 having an arcuate cross section is formed, and an inner diameter surface 16b formed in a cylindrical surface. An annular labyrinth gap δ is formed between the inner diameter surface 16 b and the step portion 28 of the outer member 27, and an axial labyrinth is formed between the tip portion of the umbrella portion 29 and the wall surface 28 a of the step portion 28. A gap δa is formed to constitute an L-shaped labyrinth seal. Here, the labyrinth gap δa in the axial direction is set in a range of 0.2 to 1.0 mm. When the labyrinth gap δa is less than 0.2 mm, the tip end surface of the umbrella part 29 may interfere with the wall surface 28a of the outer member 27 due to dimensional variation or eccentricity of the umbrella part 29 or the outer member 27, and the like. If it exceeds 1.0 mm, it is not preferable because muddy water or the like easily enters.

  As described above, in this embodiment, muddy water is applied to the sliding contact portion between the seal 8 and the metal ring 12 by the labyrinth effect formed by the umbrella portion 29 and the step portion 28 of the outer member 27 as in the above-described embodiment. And the like, and the deflector member 26 is formed by vulcanization molding of the metal ring 12 with synthetic rubber, so that variations in manufacturing dimensions can be suppressed, and the labyrinth gap δ is set narrow. In addition, since the annular groove 25 is formed on the outer diameter surface 29a of the umbrella portion 29, muddy water or the like that is about to enter between the side surface 6c of the wheel mounting flange 6 and the disc portion 12c of the metal ring 12 or the like. The foreign matter can be reduced by flowing into the lower portion (road surface side) by the annular groove 25. Furthermore, in addition to these effects, the labyrinth effect is further exhibited by the L-shaped labyrinth seal formed by the umbrella portion 29 and the step portion 28 of the outer member 27, and the muddy water resistance can be improved. .

  The embodiment shown in FIG. 7 is basically the same as that of the same component, except that the shape of the umbrella portion 29 and the outer member 27 of the deflector member 26 of the above-described embodiment (FIG. 6) is different. Parts and parts having functions are denoted by the same reference numerals, and detailed description thereof is omitted.

  Similar to the above-described embodiment, the metal ring 12 is fitted to the inner side base portion 6 b of the wheel mounting flange 6, and the outer side seal 8 is disposed so as to be in sliding contact with the metal ring 12. The deflector member 30 is integrally joined to the bent portion 12d of the metal ring 12 by vulcanization adhesion.

  The outer peripheral end 31 of the outer member 31 has a cylindrical outer peripheral surface 31a, and an annular step 28 is formed at the end of the outer peripheral surface 31a. The deflector member 30 is made of synthetic rubber such as NBR, extends from the base portion 15a to the outer side, has an elastic lip 15b having a triangular cross section, extends from the base portion 15a to the inner side, and the outer peripheral surface of the outer member 31. An umbrella portion 32 that covers 31 a and the step portion 28 is provided. The umbrella portion 32 is formed in a tapered shape in which the outer diameter surface 32a of the tip portion is gradually reduced in diameter toward the inner side, and the inner diameter along the outer peripheral surface 31a of the outer member 31 and the outer shape of the step portion 28. Surfaces 32c and 32b are provided. An annular labyrinth gap δ is formed between the inner diameter surface 32 b and the step portion 28 of the outer member 31, and an axial labyrinth gap δa is formed between the umbrella portion 32 and the wall surface 28 a of the step portion 28. Further, since a labyrinth gap δ is formed between the outer peripheral surface 31a of the outer member 31 and the inner diameter surface 32c of the umbrella portion, a crank-shaped labyrinth seal is configured.

  As described above, in the present embodiment, in addition to the effects of the above-described embodiments, the influence of the centrifugal force accompanying the rotation of the metal ring 12 can be minimized, and the outer peripheral surfaces of the umbrella portion 32 and the outer member 31 can be reduced. The labyrinth section is extended by the crank-shaped labyrinth seal formed by 31a and the stepped portion 28, and the muddy water resistance can be further improved.

  The embodiment shown in FIG. 8 is basically the same as the same part or a part having the same function, except that the shape of the umbrella part 32 of the deflector member 30 of the above-described embodiment (FIG. 7) is different. Parts are denoted by the same reference numerals and detailed description thereof is omitted.

  Similar to the above-described embodiment, the metal ring 12 is fitted to the inner side base portion 6 b of the wheel mounting flange 6, and the outer side seal 8 is disposed so as to be in sliding contact with the metal ring 12. The deflector member 33 is integrally joined to the bent portion 12d of the metal ring 12 by vulcanization adhesion.

  The deflector member 33 is made of a synthetic rubber such as NBR, and extends from the thick base 33a to the outer side, the elastic lip 15b having a triangular cross section, and extends from the base 33a to the inner side. An umbrella portion 34 is provided to cover the outer peripheral surface 31 a of 31 and the step portion 28. The umbrella portion 34 has an outer diameter surface 34a formed in a tapered shape that gradually decreases in diameter toward the inner side, an outer diameter surface 31a of the outer member 31, and inner diameter surfaces 32c and 32b along the outer shape of the step portion 28. It is equipped with. An annular labyrinth gap δ is formed between the inner diameter surfaces 32c and 32b and the step portion 28 and the outer peripheral surface 31a of the outer member 31, and a shaft is provided between the umbrella portion 34 and the wall surface 28a of the step portion 28. A labyrinth gap δa in the direction is formed, and a crank-shaped labyrinth seal is configured.

  As described above, in this embodiment, in addition to the effects of the above-described embodiment, the base portion 33a of the deflector member 33 is formed thick in combination with the outer diameter surface 34a formed in a tapered shape. The rigidity of the portion 34 is increased, and the influence of the centrifugal force accompanying the rotation of the metal ring 12 can be minimized.

  The embodiment shown in FIG. 9 is basically the same for the same parts or parts having the same function or the same function, except that the metal ring 12 of the above-described embodiment (FIG. 8) is partially different. Reference numerals are assigned and detailed description is omitted.

  A metal ring 35 is fitted on the inner base 6 b of the wheel mounting flange 6, and the outer seal 8 is disposed so as to be in sliding contact with the metal ring 35. The metal ring 35 is formed by press working from a steel plate having corrosion resistance, such as an austenitic stainless steel plate, a ferritic stainless steel plate, or a cold-rolled steel plate that has been rust-proofed, and is attached to the shoulder portion 4e of the hub ring 4. A cylindrical fitting portion 12a to be fitted, a curved portion 12b formed in an arc shape corresponding to the base portion 6b formed in an arc shape, and a wheel mounting flange extending radially outward from the curved portion 12b. A disc portion 12c that is in close contact with the inner side surface 6c, and a bent portion 12d that extends radially outward from the outer diameter portion of the disc portion 12c in the axial direction with respect to the wheel mounting flange 6. And a distal end portion 35a extending from the bent portion 12d so as to be inclined outward in the radial direction. The deflector member 33 is integrally joined by vulcanization bonding from the bent portion 12d of the metal ring 35 to the tip portion 35a.

  Thus, in this embodiment, in addition to the effects of the above-described embodiment, the rigidity of the metal ring 35 is increased, and as a result, the umbrella portion is coupled with the increase in rigidity due to the thickening of the base portion 33a of the deflector member 33. The rigidity of 34 becomes high, and the influence of the centrifugal force accompanying the rotation of the metal ring 35 can be minimized.

  The embodiment of the present invention has been described above, but the present invention is not limited to such an embodiment, and is merely an example, and various modifications can be made without departing from the scope of the present invention. Of course, the scope of the present invention is indicated by the description of the scope of claims, and further, the equivalent meanings described in the scope of claims and all modifications within the scope of the scope of the present invention are included. Including.

  The wheel bearing device according to the present invention can be applied to a third-generation or fourth-generation wheel bearing device in which an inner rolling surface is directly formed on a hub wheel, regardless of whether it is for driving wheels or driven wheels. it can.

DESCRIPTION OF SYMBOLS 1 Inner member 2, 19, 27, 31 Outer member 2a Outer rolling surface 2b Car body mounting flange 2c, 31a Outer peripheral surface 3 Rolling body 4 Hub wheel 4a, 5a Inner rolling surface 4b Small diameter step part 4c Clamping part 4d Serration 4e Hub ring shoulder 5 Inner ring 6 Wheel mounting flange 6a Hub bolt 6b Base 6c Inner side surface 7 Cage 8, 17 Outer side seal 9 Inner side seal 10 Seal plate 11 Slinger 12, 35 Metal ring 12a Fitting Part 12b Curved part 12c Disc part 12d Bent part 13, 20 Core metal 14, 21 Seal member 14a, 21a, 21b Side lip 14b Dustrip 14c, 21c Grease lip 15, 18, 23, 26, 30, 33 Deflector member 15a 33a Deflector member base 15b Elastic lips 16, 22, 24, 29, 32, 34 Umbrella 16 , 22a, 24a, 29a, 32a, 34a Umbrella part outer diameter surface 16b, 22b, 32b, 32c Umbrella part inner diameter surface 25 Annular groove 28 Step part 28a Step part wall surface 35a Tip part 50 Wheel bearing device 51 Outside Member 51a Chamfered portion 52 Inner member 53 Seal 54 Hub wheel 54a Shoulder portion 55 Wheel mounting flange 55a Side surface 56 of wheel mounting flange Base 57 Metal ring 57a Fitting portion 57b Curved portion 57c Disc portion 57d Umbrella portion 57e Bent portion 58 Seal member 58a, 58b Side lip 58c Grease lip 59 Metal core 60 Ball A Annular gaps F1, F2, F3 Centrifugal force P Rotating shaft r Radius of curvature of base arc surface R Radius of curvature of metal ring β1 Outer member Inclination angle β2 of the inner surface of the umbrella portion δ, δa Labyrinth gap θ1 Inclination angle of the tapered surface of the outer member θ2 Inclination angle of the umbrella portion

Claims (8)

An outer member integrally having a vehicle body mounting flange to be attached to the suspension device on the outer periphery, and an outer rolling surface of a double row integrally formed on the inner periphery;
A wheel mounting flange for integrally mounting a wheel at one end, an inner rolling surface facing one of the outer rolling surfaces of the double row on the outer periphery, and a small diameter step extending in the axial direction from the inner rolling surface Hub ring formed with a portion, and an outer joint member of an inner ring or a constant velocity universal joint that is fitted to the hub ring and has an inner rolling surface that is opposed to the other of the double row outer rolling surfaces on the outer periphery. An inner member comprising:
A double row rolling element housed so as to be freely rollable between both rolling surfaces of the inner member and the outer member;
A seal mounted on both side openings of an annular space formed between the outer member and the inner member;
Among these seals, the outer seal is composed of a core metal fitted to the inner periphery of the end of the outer member, and a seal member integrally joined to the core metal,
In the wheel bearing device in which the base portion on the inner side of the wheel mounting flange is formed in an arc shape in cross section, a metal ring is fitted to the base portion, and the seal member is slidably contacted with the metal ring,
The metal ring includes a cylindrical fitting portion that is externally fitted to a shoulder portion of the hub wheel, a curved portion that is formed in a cross-section arc shape corresponding to the base portion that is formed in a cross-section arc shape, and the curve A disc portion extending radially outward from the portion and being in close contact with the inner side surface of the wheel mounting flange, and an annular deflector member made of synthetic rubber is joined to the metal ring. The deflector member extends from the inner part to the inner side, and includes an umbrella part that covers the outer peripheral surface of the outer side end of the outer member, and a labyrinth seal is formed between the umbrella part and the outer peripheral surface of the outer member A bearing device for a wheel, characterized in that   The wheel bearing device according to claim 1, wherein an umbrella portion of the deflector member is formed in a spire shape in cross section.   The wheel bearing device according to claim 1, wherein an annular groove is formed on an outer diameter surface of the umbrella portion of the deflector member.   An annular step portion is formed on the outer periphery of the outer side end portion of the outer member, and the deflector member includes an umbrella portion that extends from the base portion to the inner side and covers the step portion of the outer member, An annular gap is formed between the inner diameter surface of the umbrella part and the step part, and an axial gap is formed between the tip part of the umbrella part and the wall surface of the step part, thereby forming an L-shaped labyrinth seal. The wheel bearing device according to claim 1 or 3, wherein   The wheel bearing device according to claim 1, wherein a base portion of the deflector member is formed thick.   The metal ring has a bent portion extending radially outward from the outer diameter portion of the disc portion in an axial direction with respect to the wheel mounting flange, and further inclined radially outward from the bent portion. The wheel bearing device according to claim 1, further comprising: a tip portion extending in a bent manner, wherein the deflector member is integrally joined from the bent portion of the metal ring to the tip portion.   2. The deflector member according to claim 1, further comprising an elastic lip extending from an outer side of the deflector member and having a triangular cross section, and the elastic lip is in elastic contact with an inner side surface of the wheel mounting flange. Wheel bearing device.   The wheel bearing device according to claim 1, wherein a labyrinth gap between the umbrella portion of the deflector member and the outer peripheral surface of the outer member is set in a range of 0.2 to 1.0 mm (diameter).

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