JP2018100684A - Bearing device for wheel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bearing device for a wheel capable of holding grease sealed to lubricate a rolling element at a position of a rolling face of the rolling element, and achieving reduction of a grease sealing amount and elongation of a bearing.SOLUTION: In a bearing device for a wheel, including an outer ring 2 as an outer member, a hub ring 3 and an inner ring 4 as inner members, and a seal member 6 for sealing between the outer member and the inner member, a shoulder portion 4c of which a diameter is expanded to a radial outer side with respect to a fixing face to a cylindrical portion 8a, of the inner ring 4 is disposed on an outer peripheral face at an inner-side opening portion 2a with respect to an inner rolling face 4a of the inner ring 4, an annular storage lip 10 composed of an elastic member is disposed on an end portion opposed to the shoulder portion 4c of the cylindrical portion 8a, and the storage lip 10 is brought into contact with the shoulder portion 4c and bent to a radial outer side by fitting a slinger 8 to an outer peripheral portion of the inner ring 4 so that a tip of the storage lip 10 is projected to the radial outer side with respect to the outer peripheral face of the shoulder portion 4c.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a wheel bearing device. More specifically, the present invention relates to a wheel bearing device including a seal member that holds grease sealed inside at a position where a rolling surface of a rolling element is provided.

  2. Description of the Related Art Conventionally, a wheel bearing device that rotatably supports a wheel in a suspension device such as an automobile is known. In a wheel bearing device, a hub wheel (inner member) connected to a wheel is rotatably supported by an outer member via a rolling element. Grease that promotes lubrication of the rolling elements is enclosed in the rolling surface on which the rolling elements are disposed. If the grease is reduced or rainwater or dust enters, the rolling elements and rolling surface will be damaged and the bearing life will be shortened. For this reason, in the wheel bearing device, an outer member and an inner member are provided to prevent leakage of grease sealed in the rolling surface of the rolling element and to prevent rainwater and dust from entering from the outside. A seal member is provided therebetween.

  In such a wheel bearing device, there is one in which a sealing member is provided with a plurality of sealing mechanisms to improve sealing performance. With this configuration, the seal mechanism forms a labyrinth, and the labyrinth suppresses rainwater and dust from entering the tip of the seal lip, prevents damage to the tip of the seal lip, and improves the sealing performance. For example, as described in Patent Document 1.

  The wheel bearing device described in Patent Document 1 includes a cylindrical outer member, an inner ring constituting the inner member, a rolling element that rotatably supports the inner ring, and a seal member that seals the opening. To do. A shoulder is provided on the inner ring. The seal member is composed of a pack seal in which a seal plate fitted to the outer member and a slinger fitted to the inner ring are arranged to face each other. The seal plate is formed with an oil retaining seal lip that protrudes in the axial direction toward the space where the rolling elements are installed. The labyrinth is constituted by the seal member with the oil lip seal lip opposed to the shoulder stepped surface through a slight radial gap. The seal member is provided with a plurality of seal lips so that muddy water or the like that has passed through the non-contact labyrinth does not enter the inside of the bearing device. As described above, the wheel bearing device is configured so that the sealing performance is improved by the plurality of seal lips so that muddy water or the like that has passed through the labyrinth does not enter the inside of the bearing device.

Japanese Patent No. 5821437

  However, in the wheel bearing device, the grease was scraped out by the rolling elements and easily moved to the inner side. Further, in the seal member described in Patent Document 1, even when the oil lip seal lip is provided, the grease scraped out by the rotation of the rolling elements is separated from the outer peripheral surface of the oil lip seal lip and the outer ring. Since it moves to the storage space formed by the inner peripheral surface of the axial end portion and the side surface of the seal plate on the inner space side, it is difficult to hold the grease at the position where the rolling surface of the rolling element is provided. It was. When the amount of grease charged on the rolling surface of the rolling element decreases, attention must be paid to wear and damage on the rolling surface of the rolling element of the wheel bearing device when the axle is rotated.

  The present invention has been made in view of the above situation, and the grease sealed for lubricating the rolling element is held at the position where the rolling surface of the rolling element is provided, and leakage of grease to the outside is prevented. An object of the present invention is to provide a bearing device for a wheel to prevent.

  That is, in a wheel bearing device, an outer member in which a double row outer rolling surface is integrally formed on the inner periphery, a hub wheel in which a small-diameter step portion extending in the axial direction is formed on the outer periphery, and the hub wheel An inner member having at least one inner ring press-fitted into the small-diameter step portion, and an outer member formed with a double row inner rolling surface facing the double row outer rolling surface on the outer periphery, and the outer member For a wheel provided with a double row rolling element housed between the rolling surfaces of the inner member so as to roll freely, and a seal member that seals between the outer member and the inner member. In the bearing device, the seal member includes a seal plate including a fitting portion fitted into the opening of the outer member and an inner diameter portion extending radially inward from the end portion, and an outer peripheral portion of the inner member. A cylindrical portion fitted to the end portion and extending radially outward from the end thereof, and arranged closer to the opening than the inner diameter portion. And at least one seal lip made of an elastic body is provided on the inner diameter portion, and the outer lip and the inner member are formed by contacting the seal lip with the slinger. The outer ring surface of the inner ring is closer to the opening side than the inner raceway surface of the inner ring, and a shoulder portion whose diameter is increased radially outward from the fitting surface with the cylindrical portion of the inner ring is provided. An annular storage lip made of an elastic member is provided at an end of the slinger facing the shoulder, and the slinger is fitted to the outer periphery of the inner member. Thus, it comes into contact with the shoulder and bends radially outward, and the tip of the storage lip projects radially outward from the outer peripheral surface of the shoulder.

  In the wheel bearing device, the peripheral surface of the shoulder facing the storage lip is formed in a shape having a curvature in the axial cross section.

  In the wheel bearing device, the diameter is increased from the proximal end portion on the cylindrical portion side toward the distal end side.

  In the wheel bearing device, a groove is provided at the base end portion of the outer peripheral surface of the storage lip.

  In the wheel bearing device, a plurality of grooves are provided on the outer peripheral surface of the storage lip.

  In the wheel bearing device, the seal plate includes a cylindrical portion that protrudes in the axial direction from the standing plate portion, and the cylindrical portion and the storage lip overlap in a radial view.

  As effects of the present invention, the following effects can be obtained.

  That is, according to the present invention, a weir that inhibits the movement of grease is formed by the shoulder portion and the storage lip, and the grease scraped from the rolling surface by the rolling element is inhibited from moving to the inner side. Thereby, the grease sealed for lubricating the rolling elements can be held at the position where the rolling surfaces of the rolling elements are provided.

  According to the present invention, since the peripheral surface of the shoulder portion facing the storage lip is formed in a shape having a curvature in the axial cross section, when the slinger is fitted to the outer peripheral portion of the inner member. In contact with the shoulder, the outer peripheral surface of the outer end of the storage lip is guided radially outward. Thereby, it becomes easy to form the weir by the storage lip, and the grease scraped off from the rolling surface by the rolling element can be prevented from moving to the inner side.

  According to the present invention, since the inner diameter of the storage lip is inclined in the direction of increasing the diameter from the cylindrical portion side end toward the other end, the slinger is fitted to the outer peripheral portion of the inner member. In contact with the shoulder, the outer peripheral surface of the outer end of the storage lip is guided radially outward. Thereby, it becomes easy to form the weir by the storage lip, and the grease scraped off from the rolling surface by the rolling element can be prevented from moving to the inner side.

  According to the present invention, since the first groove is provided on the outer peripheral surface on the base end side of the storage lip, the base of the storage lip is easily bent. Thereby, it becomes easy to form the weir by the storage lip, and the grease scraped off from the rolling surface by the rolling element can be prevented from moving to the inner side.

  According to the present invention, since the plurality of second grooves are provided on the outer peripheral surface of the storage lip, it is easy to bend in the direction of expanding the diameter in the range where the second groove is provided in the storage lip. Thereby, it becomes easy to form the weir by the storage lip, and the grease scraped off from the rolling surface by the rolling element can be prevented from moving to the inner side.

  According to the present invention, since the cylindrical portion and the storage lip inhibit the flow of grease, it is possible to prevent the grease scraped out by the rolling elements from moving to the seal lip side.

The perspective view which shows the whole structure in 1st embodiment of the wheel bearing apparatus which concerns on this invention. Sectional drawing which shows the whole structure in 1st embodiment of the wheel bearing apparatus which concerns on this invention. The expanded sectional view which shows the structure of the inner ring | wheel, the outer ring | wheel, and a sealing member in 1st embodiment of the wheel bearing apparatus which concerns on this invention. (A) Enlarged sectional view showing the configuration of the sealing member in the middle of fitting the slinger to the outer peripheral portion of the inner ring in the first embodiment of the wheel bearing device according to the present invention, (B) Enlarging also shows the configuration of the storage lip Sectional drawing. The expanded sectional view which shows the structure of the inner ring | wheel and the seal member of the state which made the storage lip contact the shoulder part in 1st embodiment of the wheel bearing apparatus which concerns on this invention. The expanded end elevation which shows the structure of the inner ring | wheel, the outer ring | wheel, and a sealing member in 2nd embodiment of the wheel bearing apparatus which concerns on this invention. (A) The expanded sectional view which shows the structure of the sealing member in 4th embodiment of the wheel bearing apparatus which concerns on this invention, (B) The expanded sectional view which similarly shows the structure of a storage lip.

  Below, the wheel bearing apparatus 1 which is 1st embodiment of the wheel bearing apparatus which concerns on this invention using FIGS. 1-3 is demonstrated.

  As shown in FIGS. 1 and 2, the wheel bearing device 1 supports a wheel rotatably in a suspension device of a vehicle such as an automobile. The wheel bearing device 1 includes an outer ring 2 that is an outer member, a hub ring 3 that is an inner member, an inner ring 4, two rows of inner side balls 5a (see FIG. 2) that are rolling rows, and an outer side ball row. 5b (refer FIG. 2), the inner side sealing member 6, and the outer side sealing member 9 (refer FIG. 2) are comprised.

  As shown in FIG. 2, the outer ring 2 that is an outer member supports a hub ring 3 and an inner ring 4 that are inner members. The outer ring 2 is made of, for example, a medium-high carbon steel containing 0.40 to 0.80 wt% of carbon such as S53C formed in a substantially cylindrical shape. In the outer ring 2, an inner side opening 2 a into which the inner side seal member 6 can be fitted is formed at the inner side end of the outer ring 2 arranged on the vehicle body side when the vehicle is mounted. In the outer ring 2, an outer side opening 2 b into which the outer side seal member 9 can be fitted is formed at an outer side end disposed on the wheel side when the vehicle is mounted. Here, the inner side represents the vehicle body side of the wheel bearing device 1 when attached to the vehicle body, and the outer side represents the wheel side of the wheel bearing device 1 when attached to the vehicle body.

  On the inner peripheral surface of the outer ring 2, an annular outer side rolling surface 2 c and an outer side outer rolling surface 2 d are formed in parallel to each other in the circumferential direction. The outer rolling surface 2d on the outer side is formed so that the inner side outer rolling surface 2c and the pitch circle diameter are equal or larger. A hardened layer having a surface hardness in the range of 58 to 64 HRC is formed, for example, by induction hardening on the inner side outer raceway 2c and the outer side outer raceway 2d. On the outer peripheral surface of the outer ring 2, a vehicle body attachment flange 2e for attaching to a knuckle of a suspension device (not shown) is integrally formed in the vicinity of the inner side opening 2a.

  The hub wheel 3 constituting the inner member rotatably supports a vehicle wheel (not shown). The hub ring 3 is formed in a bottomed cylindrical shape, and is made of, for example, medium-high carbon steel containing 0.40 to 0.80 wt% of carbon such as S53C. In the hub wheel 3, a small-diameter step portion 3a having a reduced diameter on the outer peripheral surface is formed at an inner side end portion disposed on the vehicle body side when the vehicle is mounted. In the hub wheel 3, a wheel mounting flange 3 b for mounting a wheel is integrally formed at an outer side end disposed on the wheel side when the vehicle is mounted. The wheel mounting flange 3b is provided with hub bolts 3d at equal circumferential positions. The hub wheel 3 is disposed such that the inner rolling surface 3 c formed on the outer side faces the outer rolling surface 2 d on the outer side of the outer ring 2.

  The hub wheel 3 is hardened to a surface hardness of 58 to 64 HRC by induction hardening from the inner-side small-diameter step portion 3a to the outer-side inner rolling surface 3c to the lip contact surface of the outer-side seal member 9. ing. Thereby, the hub wheel 3 has sufficient mechanical strength against the rotational bending load applied to the wheel mounting flange 3b, and the durability of the hub wheel 3 is improved. The hub ring 3 is provided with an inner ring 4 constituting an inner member in a small diameter step portion 3a. The inner rolling surface 4 a formed on the inner ring 4 at the inner side end portion faces the outer rolling surface 2 c on the inner side of the outer ring 2, and the inner rolling surface 3 c formed on the outer side is the outer ring 2 of the outer ring 2. The hub wheel 3 is disposed so as to face the outer rolling surface 2d on the side.

  The inner ring 4 constituting the inner member is a rolling train that preloads the inner side ball row 5a arranged on the vehicle body side when mounted on the vehicle and the outer side ball row 5b arranged on the wheel side when mounted on the vehicle side. is there. The inner ring 4 is formed in a cylindrical shape. The inner ring 4 is made of, for example, high carbon chrome bearing steel such as SUJ2, and is hardened in the range of 58 to 64 HRC up to the core portion by quenching. On the outer peripheral surface of the inner ring 4, an annular inner rolling surface 4a is formed in the circumferential direction. The inner ring 4 is integrally fixed to the inner side end portion of the hub wheel 3 by caulking while a predetermined preload is applied by press fitting. That is, the inner raceway 4 a is formed by the inner race 4 on the inner side of the hub race 3. Further, a shoulder portion 4c having a diameter increased radially outward is provided on the outer peripheral surface of the inner ring 4 and on the outer peripheral surface on the inner side opening 2a side than the inner rolling surface 4a. Details of the shoulder 4c will be described later.

  The inner side ball row 5a and the outer side ball row 5b, which are rolling rows, support the hub wheel 3 rotatably. The inner side ball row 5a and the outer side ball row 5b are obtained by holding a plurality of balls, which are rolling elements, in an annular shape by a cage. The inner side ball row 5a and the outer side ball row 5b are made of, for example, high carbon chrome bearing steel such as SUJ2, and are hardened in a range of 58 to 64 HRC to the core portion by quenching. The inner side ball row 5a is sandwiched between the inner raceway surface 4a of the inner ring 4 and the outer raceway surface 2c on the inner side of the outer race 2 so as to be freely rollable. The outer side ball row 5b is sandwiched between the inner raceway surface 3c of the hub wheel 3 and the outer raceway surface 2d on the outer side of the outer ring 2 so as to be freely rollable. That is, the inner side ball row 5 a and the outer side ball row 5 b support the hub wheel 3 and the inner ring 4 so as to be rotatable with respect to the outer ring 2.

  In the wheel bearing device 1, a double-row angular ball bearing is constituted by an outer ring 2, a hub ring 3, an inner ring 4, an inner side ball row 5 a and an outer side ball row 5 b. In the present embodiment, the wheel bearing device 1 is configured with a double-row angular contact ball bearing, but is not limited thereto, and may be configured with a double-row tapered roller bearing or the like.

  As shown in FIGS. 2 and 3, the inner side sealing member 6 closes a gap between the inner side opening 2 a of the outer ring 2 that is an outer member and the inner ring 4 that is an inner member. The inner side sealing member 6 includes a substantially cylindrical sealing plate 7 and a substantially cylindrical slinger 8.

  As shown in FIG. 3, the seal plate 7 is composed of a core metal 7a and a seal lip 7b. The core 7a is made of a ferritic stainless steel plate (JIS standard SUS430 or the like), an austenitic stainless steel plate (JIS standard SUS304 or the like), or a rust-proof cold rolled steel plate (JIS standard SPCC or the like). It is composed of The core metal 7a is formed in a substantially L shape in an axial cross-sectional view by bending an outer edge portion of an annular steel plate by press working. Thereby, the metal core 7a includes a fitting portion 7c that can be fitted into the inner side opening 2a of the outer ring 2, and an annular inner diameter portion 7d that extends from the end portion toward the axial center. A seal lip 7b, which is an elastic member, is vulcanized and bonded to a part of the outer peripheral surface of the fitting portion 7c fitted to the inner side opening 2a. A radial lip 7e (grease lip), an axial lip 7f (side lip) and an annular portion 7g constituting the seal lip 7b are integrally vulcanized and bonded to one side surface of the inner diameter portion 7d. Radial lip 7e, axial lip 7f, and ring portion 7g are NBR (acrylonitrile-butadiene rubber), HNBR (hydrogenated acrylonitrile-butadiene rubber), EPDM (ethylene propylene rubber), heat resistance, chemical resistance. It is made of synthetic rubber such as ACM (polyacrylic rubber), FKM (fluororubber), or silicon rubber, which is excellent in. The seal plate 7 has a fitting portion 7 c fitted into the inner side opening 2 a of the outer ring 2 with the inner diameter portion 7 d facing the inner side (outer side) of the outer ring 2. The annular portion 7g is in the vicinity of the radially inner end of the inner diameter portion 7d and protrudes toward the outer side.

  The slinger 8 is made of a steel plate equivalent to the seal plate 7. The slinger 8 is formed in a substantially L shape in an axial cross-sectional view by bending an outer edge portion and an inner edge portion of an annular steel plate by press working. Thereby, the slinger 8 has a cylindrical portion 8a that can be fitted to the outer peripheral surface 4b that is a fitting surface of the inner ring 4, and an annular upright plate portion 8b that extends radially outward from the end of the cylindrical portion 8a. It is composed of In the slinger 8, the cylindrical portion 8 a is fitted to the outer peripheral surface 4 b of the inner ring 4 with the standing plate portion 8 b facing the outer side (inner side) of the outer ring 2. The slinger 8 is fixed to the inner ring 4 at a position outside the outer ring 2 relative to the seal plate 7. At this time, the slinger 8 is disposed so that the inner side surface (outer side surface) of the upright plate portion 8 b faces the outer side surface (inner side surface) of the inner diameter portion 7 d of the seal plate 7. Further, the standing plate portion 8 b is formed to have an outer diameter smaller than the inner diameter of the fitting portion 7 c of the seal plate 7. That is, the standing plate portion 8b is arranged inside the fitting portion 7c. A magnetic encoder 8c is provided on the outer surface of the upright plate portion 8b.

  Thus, the inner side seal member 6 is disposed so that the seal plate 7 fitted to the inner side opening 2a of the outer ring 2 and the slinger 8 fitted to the inner ring 4 face each other, thereby constituting a pack seal. doing. The radial lip 7e of the seal plate 7 is in contact with the cylindrical portion 8a of the slinger 8 through an oil film, thereby preventing leakage of grease inside the wheel bearing device 1 to the outside. The axial lip 7f of the seal plate 7 is in contact with the standing plate portion 8b of the slinger 8 via an oil film to prevent entry of muddy water or the like from the outside of the wheel bearing device 1. The inner side sealing member 6 is configured to be slidable with respect to the slinger 8 when the radial lip 7e and the axial lip 7f of the seal plate 7 contact the slinger 8 through an oil film. Thereby, the inner side sealing member 6 prevents the leakage of grease from the inner side opening 2a of the outer ring 2 and the entry of rainwater, dust and the like from the outside.

  As shown in FIG. 2, the outer side sealing member 9 closes the gap between the outer side opening 2 b of the outer ring 2 and the hub ring 3. The outer side seal member 9 is configured as an integral seal in which a seal lip 9b is vulcanized and bonded to a substantially cylindrical cored bar 9a.

  The core 9a of the outer side seal member 9 is made of a ferritic stainless steel plate (JIS standard SUS430 or the like), an austenitic stainless steel plate (JIS standard SUS304 or the like), or a rust-proof cold rolled steel plate (JIS). Standard SPCC system). The core metal 9a is formed in a substantially L shape in an axial cross-sectional view by bending an outer edge portion of an annular steel plate by press working. Seal lip 9b is NBR (acrylonitrile-butadiene rubber), HNBR (hydrogenated acrylonitrile-butadiene rubber) with excellent heat resistance, EPDM (ethylene propylene rubber), ACM (polyacrylic rubber) with excellent heat resistance and chemical resistance , FKM (fluoro rubber), or synthetic rubber such as silicon rubber.

  The cored bar 9 a is fitted in the outer side opening 2 b of the outer ring 2. At this time, the outer side seal member 9 is disposed so that the seal lip 9 b contacts the seal sliding surface of the hub wheel 3. The outer side seal member 9 is configured to be slidable with respect to the seal sliding surface when the seal lip 9b comes into contact with the seal sliding surface of the hub wheel 3 through the oil film. Thereby, the seal lip 9b of the outer side seal member 9 prevents leakage of grease from the outer side opening 2b of the outer ring 2 and entry of rainwater, dust, and the like from the outside.

  In the wheel bearing device 1 configured as described above, the hub wheel 3 and the inner ring 4 are rotatably supported by the outer ring 2 via the inner side ball row 5a and the outer side ball row 5b. In the wheel bearing device 1, the gap between the inner side opening 2 a of the outer ring 2 and the inner ring 4 is closed by the inner side seal member 6, and the gap between the outer side opening 2 b of the outer ring 2 and the hub ring 3 is closed. The outer side sealing member 9 is closed. Thus, in the wheel bearing device 1, the hub ring 3 and the inner ring 4 supported by the outer ring 2 rotate while preventing leakage of grease from the inside and entry of rainwater, dust, and the like from the outside.

Next, the seal plate 7, slinger 8 and inner ring 4 constituting the inner side seal member 6 will be described in detail with reference to FIGS. 3 and 4.
As shown in FIG. 3 and FIG. 4 (A), the grease inside the wheel bearing device 1 is held on the outer peripheral surface of the inner ring 4 at the position where the rolling surface of the rolling element (here, ball) is provided. A shoulder portion 4c is formed. The shoulder portion 4c is formed in an annular shape having a larger outer diameter than the outer peripheral surface 4b that is a fitting surface into which the cylindrical portion 8a of the slinger 8 is fitted. That is, the shoulder 4 c protrudes in the radial direction as compared with the outer peripheral surface 4 b of the inner ring 4. The shoulder 4c has an outer peripheral surface 4d and an inner peripheral surface 4e. The outer side peripheral surface 4d is a peripheral surface formed continuously with the inner rolling surface 4a in an axial sectional view, and is formed so as to incline toward the outer side as it goes radially outward.

  The inner side peripheral surface 4e is a peripheral surface formed continuously with the outer peripheral surface 4b with which the cylindrical portion 8a is fitted in the axial sectional view, and is a peripheral surface on the side facing the storage lip 10 described later. The inner side peripheral surface 4e is formed in a shape having a curvature in an axial sectional view. In more detail, the inner side peripheral surface 4e is formed in the curved surface which becomes concave to an outer side and radial direction center part side. In other words, the inner peripheral edge surface 4e is formed as a curved surface that smoothly connects the outer peripheral surface 4b into which the cylindrical portion 8a is fitted and the radially outer tip of the shoulder portion 4c.

  The fitting part 7 c is fitted into the inner side opening 2 a of the outer ring 2 with the inner diameter part 7 d facing the inner side of the outer ring 2. That is, the outer peripheral surface of the fitting portion 7c is formed in a cylindrical shape with an outer diameter that allows the cored bar 7a to be fitted into the inner side opening 2a. The inner peripheral surface of the fitting portion 7 c is formed so that the inner diameter becomes larger toward the outer side of the outer ring 2. That is, the inner peripheral surface of the fitting portion 7c has a diameter from the inner side of the outer ring 2 on the base end side (outer side) to which the inner diameter portion 7d is connected to the outer side of the outer ring 2 on the distal end side (inner side). A seal lip 7b (a dark thin ink portion) covers the cored bar 7a so as to be inclined outward in the direction (see FIG. 3).

  In the slinger 8, a storage lip 10 (a dark thin ink portion) is provided at an end portion facing the shoulder portion 4 c of the cylindrical portion 8 a, in other words, an end portion on the outer side. The storage lip 10 is elastically deformed to expand radially outward to form a weir. The storage lip 10 holds the grease inside the wheel bearing device 1 on the rolling surface of the rolling element. The storage lip 10 is formed in an annular shape and is made of an elastic member. Specifically, the storage lip 10 is made of an elastic rubber which is the same material as the seal lip 7b, and is NBR (acrylonitrile-butadiene rubber), HNBR (hydrogenated acrylonitrile-butadiene rubber) excellent in heat resistance, It is composed of synthetic rubber such as EPDM (ethylene propylene rubber), ACM (polyacrylic rubber), FKM (fluorine rubber), or silicon rubber having excellent heat resistance and chemical resistance. The proximal end portion of the storage lip 10 and the outer end portion of the cylindrical portion 8a are bonded together by vulcanization adhesion.

  As shown in FIG. 4B, the inner diameter of the storage lip 10 increases from the end on the cylindrical portion 8a side toward the other end. More specifically, the inner peripheral surface 10c of the storage lip 10 is inclined at an angle θ1 outward in the radial direction from the proximal end portion toward the distal end portion (outer side) in the axial sectional view.

  4B, the outer diameter A of the storage lip 10 is configured to be smaller than the outer diameter B of the cylindrical portion 8a of the slinger 8. In addition, the outer diameter A of the storage lip 10 is the outer diameter of the outer peripheral surface excluding the protruding portion that protrudes radially outward of the tip portion. With this configuration, when the inner side seal member 6 is assembled by inserting the cylindrical portion 8a of the slinger 8 into the seal plate 7, the contact pressure between the outer peripheral surface of the storage lip 10 and the lip 7e of the seal plate 7 is reduced. It becomes small and workability | operativity can be improved.

  As shown in FIG. 4B, the outer peripheral surface of the storage lip 10 is provided with a first groove 10a and a plurality of second grooves 10b. The first groove 10a facilitates elastic deformation of the storage lip 10 outward in the radial direction. The 1st groove | channel 10a is provided in the base end part side of the storage lip 10, and is formed in circular arc shape in the axial cross section view. The first groove 10 a is formed on the entire outer peripheral surface of the storage lip 10. The second groove 10b facilitates elastic deformation of the storage lip 10 radially outward, and a plurality of the second grooves 10b are provided. The plurality of second grooves 10b are formed on the entire outer peripheral surface of the storage lip 10, and are formed in a sawtooth shape in an axial sectional view. By providing the plurality of second grooves 10b, fine irregularities are formed on the outer peripheral surface of the storage lip 10 in the axial sectional view.

  With this configuration, the storage lip 10 is easily elastically deformed radially outward, and by forming the weir, the grease can be held at the position where the rolling surface of the rolling element is provided. In the present embodiment, the storage lip 10 is formed with the first groove 10a and the second groove 10b. However, the present invention is not limited to this. For example, only the first groove 10a is provided. The structure formed may be sufficient, and the structure in which only the 2nd groove | channel 10b is formed may be sufficient.

  Next, the process of fitting the inner side seal member 6 between the outer ring 2 and the inner ring 4 will be described with reference to FIGS. 3, 4, and 5. As shown in FIG. 4, the seal plate 7 and the slinger 8 constituting the inner side seal member 6 are inserted between the outer ring 2 and the inner ring 4 (see FIG. 4A, black arrows). The seal plate 7 and the slinger 8 are moved to the outer side, and the storage lip 10 provided at the end of the slinger 8 contacts the shoulder 4c of the inner ring 4. At this time, as shown in FIG. 5, the inner peripheral surface 4e is formed in a shape having a curvature, and the inner peripheral surface 10c is inclined at an angle θ1, so that the storage lip is in contact with the shoulder 4c. 10 advances to the outer side along the inner peripheral edge surface 4e (see the black arrow in FIG. 5).

  The storage lip 10 is bent outward in the radial direction when proceeding to the outer side along the inner peripheral edge surface 4e. When the storage lip 10 is bent radially outward, the groove width of the first groove 10a and the groove width of the second groove 10b provided on the outer peripheral surface thereof are reduced by elastic deformation (see arrows in FIG. 5). ). Specifically, when the storage lip 10 is bent radially outward, the outer peripheral surface of the storage lip 10 is compressed in the axial direction, and the inner peripheral surface is pulled in the axial direction. By providing the first groove 10a and the second groove 10b, the deformation on the outer peripheral side of the storage lip 10 is absorbed by the first groove 10a and the second groove 10b and is easily bent. As shown in FIG. 3, in the state in which the inner side seal member 6 is fitted between the outer ring 2 and the inner ring 4, the radial outer peripheral end of the storage lip 10 is more than the radial outer peripheral end of the shoulder 4c. Projects outward. The storage lip 10 has an inner peripheral surface 10c that is in close contact with the inner peripheral surface 4e.

  With this configuration, a weir is formed by the portion of the shoulder 4c and the storage lip 10 that protrudes outward in the radial direction. The weir functions as a weir that retains grease and is scraped by the inner side ball row 5a. Suppressed movement of the applied grease to the inner side. Further, the storage lip 10 is bent along the inner side peripheral surface 4e of the shoulder portion 4c, whereby the adhesion between the inner peripheral surface 10c of the storage lip 10 and the shoulder portion 4c is increased, and the slinger 8 and the inner ring 4 are The airtightness between them is improved.

  Moreover, the outer side edge part of the annular part 7g and the inner side peripheral surface of the part which protruded to the radial direction outer side of the storage lip 10 comprise the labyrinth 11 without contacting.

  With this configuration, in the wheel bearing device 1, the grease scraped out by the inner side ball row 5 a by the labyrinth 11 is a radial lip 7 e (grease lip) and an axial lip 7 f ( It prevents the flow toward the side lip) and prevents leakage of grease to the inner side. Further, the wheel bearing device 1 can improve the sealing performance without increasing the rotational torque. The sealing performance can be improved without increasing the effect of preventing the leakage of grease to the inner side and the rotational torque.

  Next, a wheel bearing device 21 which is a second embodiment of the wheel bearing device according to the present invention will be described with reference to FIG. The wheel bearing devices 21 and 23 according to the following embodiments are used in the description as being applied in place of the wheel bearing device 1 in the wheel bearing device 1 shown in FIGS. 1 to 5. By using names, figure numbers, and symbols, the same thing is pointed out, and in the following embodiments, specific explanations are omitted with respect to the same points as the embodiments already described, and different parts are mainly described. To do.

  As shown in FIG. 6, a cylindrical portion 7 h is provided at the radially inner end of the inner diameter portion 7 d of the seal plate 7. The cylindrical portion 7h is configured by bending a portion constituting the inner diameter portion 7d of the cored bar 7a by press working and forming an L shape in an axial sectional view. The cylindrical portion 7h is configured to overlap the storage lip 10 in the radial direction. The cylindrical portion 7 h constitutes the labyrinth 22 together with a portion protruding outward in the radial direction of the storage lip 10.

  With this configuration, the grease scraped out by the inner side ball row 5a by the labyrinth 22 flows toward the radial lip 7e (grease lip) and the axial lip 7f (side lip) constituting the seal lip 7b. This prevents the leakage of grease to the inner side. Moreover, the wheel bearing apparatus 1 can improve sealing performance.

  In the present embodiment, the cylindrical portion 7h constitutes the labyrinth 22 without contacting the storage lip 10, but is not limited thereto. For example, the cylindrical portion 7h is connected to the storage lip 10. It is good also as a structure which contacts. By comprising in this way, the clearance gap between the cylindrical part 7h and the storage lip | rip 10 is lose | eliminated, and the flow of grease can be prevented reliably.

  Next, the wheel bearing device 23 which is a third embodiment of the wheel bearing device according to the present invention will be described with reference to FIG.

  FIG. 7A is an enlarged view of the storage lip 10. As shown in FIG. 7A, the inner peripheral surface 10c of the storage lip 10 is formed in a curved surface shape. More specifically, the inner peripheral surface 10c of the storage lip 10 is formed as a curved surface that protrudes toward the outer side and the central portion in the radial direction.

  With this configuration, as shown in FIG. 7B, when the storage lip 10 contacts the shoulder 4c of the inner ring 4, the storage lip 10 that contacts the shoulder 4c is bent radially outward. It becomes easy to move along the inner side peripheral surface 4e of the shoulder 4c. That is, the inner peripheral surface 10c of the storage lip 10 and the inner side peripheral surface 4e of the shoulder portion 4c are both formed in a curved shape, whereby the inner peripheral surface 10c of the storage lip and the inner side peripheral surface 4e of the shoulder portion 4c. The contact point can be moved smoothly while moving continuously. Thereby, the inner peripheral surface 10c of the storage lip 10 and the inner side peripheral surface 4e are more closely attached, the airtightness between the slinger 8 and the inner ring 4 is improved, and the grease that moves from the outer side to the inner side is added. Large movements can be suppressed.

  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. In the present embodiment, the wheel bearing devices 1, 21, and 23 have a third-generation wheel bearing device in which the inner raceway surface 3 c of the inner side ball row 5 a is directly formed on the outer periphery of the hub wheel 3. However, the present invention is not limited to this, and may be a second generation structure in which a pair of inner rings are press-fitted and fixed to the hub wheel 3 or a first generation structure.

DESCRIPTION OF SYMBOLS 1 Wheel bearing apparatus 2 Outer ring 2a Inner side opening part 3 Hub wheel 4 Inner ring 4b Outer peripheral surface 4c Shoulder part 4d Outer side peripheral surface 4e Inner side peripheral surface 5a Inner side ball row 5b Outer side ball row 6 Seal member 7 Seal plate 7c Fitting portion 7d Inner diameter portion 8 Slinger 8a Cylindrical portion 8b Standing plate portion 10 Storage lip 10a First groove 10b Second groove 10c Inner circumferential surface

Claims (6)

An outer member in which a double row outer rolling surface is integrally formed on the inner periphery;
A hub wheel having a small-diameter step portion extending in the axial direction on the outer periphery, and at least one inner ring press-fitted into the small-diameter step portion of the hub ring, and a plurality of outer rings facing the double-row outer rolling surface on the outer periphery. An inner member in which the inner rolling surface of the row is formed;
A double row rolling element housed in a freely rolling manner between the rolling surfaces of the outer member and the inner member;
In a wheel bearing device comprising: a seal member that seals between the outer member and the inner member;
The sealing member is
A sealing plate comprising a fitting portion fitted into the opening of the outer member and an inner diameter portion extending radially inward from the end portion;
A slinger comprising a cylindrical portion fitted to the outer peripheral portion of the inner member and a standing plate portion extending radially outward from the end portion and disposed on the opening side of the inner diameter portion;
At least one seal lip made of an elastic body is provided in the inner diameter portion, and the seal lip contacts the slinger to seal between the outer member and the inner member, so that the inner ring of the inner ring is turned. On the outer peripheral surface on the opening side of the running surface, a shoulder portion is provided that has a diameter that is larger on the radially outer side than the fitting surface with the cylindrical portion of the inner ring,
An annular storage lip made of an elastic member is provided at the end of the slinger facing the shoulder,
The storage lip is bent radially outward in contact with the shoulder when the slinger is fitted to the outer periphery of the inner member, and the tip of the storage lip is the outer peripheral surface of the shoulder. Wheel bearing device that protrudes outward in the radial direction.   The wheel bearing device according to claim 1, wherein a peripheral surface of the shoulder portion on a side facing the storage lip is formed in a shape having a curvature in an axial cross section.   3. The wheel bearing device according to claim 1, wherein an inner diameter of the storage lip is increased from a proximal end portion on the cylindrical portion side toward a distal end side.   The wheel bearing device according to any one of claims 1 to 3, wherein a groove is provided at a base end portion of an outer peripheral surface of the storage lip.   The wheel bearing device according to any one of claims 1 to 4, wherein a plurality of grooves are provided on an outer peripheral surface of the storage lip. The seal plate has a cylindrical portion protruding in the axial direction from the standing plate portion,
The wheel bearing device according to any one of claims 1 to 5, wherein the cylindrical portion and the storage lip overlap in a radial view.

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