JP2020106128A - Hub unit bearing - Google Patents

Abstract

To provide a hub unit bearing which can discharge water droplets that has entered into a radial outer space of a contact lip to the outside or prevent sticking of the contact lip to a slide contact surface.SOLUTION: Multiple protrusions 40 are formed in at least one of a contact lip 33 of a seal member 16 and a cover part 36 at the radial outer side of the contact lip 33. Further, multiple protrusions 40 are formed at multiple lips 91 to 93 of a seal member 16C and a cover part 94 between the contact lips 91 to 93.SELECTED DRAWING: Figure 2

Description

The present invention relates to a hub unit bearing, and more particularly to a seal member for a hub unit bearing.

In a hub unit bearing that rotatably supports an automobile wheel with respect to a suspension device, a rotating airflow is generated around an outer ring formed in a substantially cylindrical shape by a hub flange that rotates together with the wheel when the vehicle is traveling.

Then, during running of the vehicle such as in rainy weather, the water droplets (rainwater) that are wound up by the rotating wheels are entrained in the rotating airflow and orbit the outer ring. Then, when the speed of the vehicle slows down or stops, the water droplets adhere to the outer ring due to the disappearance of the rotating airflow.

As a conventional hub unit bearing, an outboard-side sealing member that seals between the outer ring and the hub ring is provided, and the outboard-side sealing member projects in an annular weir portion that projects radially outward from the outer diameter surface of the outer ring. And a non-contact lip projecting from the weir portion to the outboard side and forming a labyrinth seal between the flange portion of the hub wheel and the side surface on the inboard side, and two contact lips that slidably contact the outer diameter surface of the hub wheel. There is known one having, (for example, refer to Patent Document 1).

International Publication No. 2017/061242

However, in the outboard-side sealing member described in Patent Document 1 described above, the non-contact lip prevents the water droplets taken into the rotating air flow from coming close to the sliding contact of the contact lip, but the non-contact lip is exceeded. The water droplets that entered the space radially outside the contact lip were taken into the rotating airflow generated in that space and were difficult to discharge. Further, due to the laminar flow of the rotating airflow generated in the space between the two contact lips, the pressure in the space may be reduced, and sticking of the contact lip to the sliding contact surface may occur.

The present invention has been made in view of the above-described problems, and an object thereof is to be able to discharge water droplets that have entered the space on the radially outer side of the contact lip to the outside, or to the sliding contact surface of the contact lip. It is an object of the present invention to provide a hub unit bearing capable of preventing sticking of the hub unit.

The above object of the present invention is achieved by the following configurations.
(1) An outer ring member, an inner ring member rotatably provided with respect to the outer ring member via a plurality of rolling elements, a retainer that holds the plurality of rolling elements at substantially equal intervals in the circumferential direction, and the outer ring A seal unit for closing at least one of an outboard side and an inboard side of a bearing internal space between a member and the inner ring member, wherein the seal member is provided on an inner diameter surface of the outer ring member. An annular cored bar to be fixed and an elastic seal part fixed to the cored bar are provided, and the elastic seal part is formed on the inner diameter side of the cored bar and is in sliding contact with the inner ring member. At least one of the contact lip and a cover formed to cover a side surface of the core bar, and at least one of the at least one contact lip and the cover radially outside the at least one contact lip. A hub unit bearing, wherein a plurality of protrusions are formed on the.
(2) The elastic seal portion further has a non-contact lip provided radially outside the at least one contact lip, and the plurality of protrusions are formed on the non-contact lip. The hub unit bearing according to (1).
(3) The plurality of protrusions are formed on the at least one contact lip, the non-contact lip, and the covering portion facing a space radially outside the at least one contact lip (2) ) Hub unit bearing described in.
(4) The plurality of protrusions are vortex generators that turbulently generate a rotating airflow generated in a space radially outside the at least one contact lip when the inner ring member rotates (1) ~ The hub unit bearing according to any one of (3).
(5) Outer ring member, inner ring member rotatably provided to the outer ring member via a plurality of rolling elements, a retainer that holds the plurality of rolling elements at substantially equal intervals in the circumferential direction, and the outer ring A seal unit for closing at least one of an outboard side and an inboard side of a bearing internal space between a member and the inner ring member, wherein the seal member is provided on an inner diameter surface of the outer ring member. An annular cored bar to be fixed and an elastic seal part fixed to the cored bar are provided, and the elastic seal part is formed on the inner diameter side of the cored bar and has a plurality of contacts slidably contacting the inner ring member. A plurality of contact lips and a plurality of protrusions are formed on at least one of the plurality of contact lips and the plurality of contact lips between the plurality of contact lips. Hub unit bearing characterized in that
(6) The hub unit bearing according to (5), wherein the plurality of protrusions are formed on the plurality of contact lips and the covering portion facing the space between the plurality of contact lips.
(7) The plurality of protrusions are vortex generators that turbulently generate a rotating airflow generated in a space between the plurality of contact lips when the inner ring member rotates (5) or (6). Hub unit bearing described in.

According to the present invention, the contact lip of the seal member and the plurality of protrusions serving as a vortex generator formed on at least one of the covering portions radially outside the contact lip cause a radial direction of the contact lip when the inner ring member rotates. The rotating airflow generated in the outer space can be made turbulent. Therefore, the laminarization of the rotating airflow in the space radially outside the contact lip prevents water droplets from being taken into the vicinity of the portion where the airflow is the fastest and rotationally moving, and the space outside the contact lip in the radial direction is prevented. Water droplets that have entered the can be discharged to the outside.

Further, according to the present invention, the plurality of contact lips of the seal member and the plurality of protrusions serving as a vortex generator formed on at least one of the covering portions between the plurality of contact lips make a plurality of contact when the inner ring member rotates. The rotating airflow generated in the space between the lips can be made turbulent. For this reason, it is possible to prevent the pressure drop in the space between the plurality of contact lips, and thus to prevent the contact lips from sticking to the sliding contact surface.

It is sectional drawing explaining 1st Embodiment of the hub unit bearing which concerns on this invention. It is an expanded sectional view of the periphery of the 1st sealing member by the side of the outboard shown in FIG. It is an expanded sectional view of the periphery of the 2nd seal member by the side of the inboard shown in FIG. It is an expanded sectional view explaining the modification of the 1st seal member of a 1st embodiment. It is an expanded sectional view of the circumference of the 1st seal member by the side of an outboard explaining the 2nd embodiment of the hub unit bearing concerning the present invention. It is an expanded sectional view of the circumference of the 2nd seal member by the side of the inboard of a 2nd embodiment. It is an expanded sectional view of the circumference of the 1st seal member by the side of an outboard explaining the 3rd embodiment of the hub unit bearing concerning the present invention. It is an expanded sectional view of the circumference of the 2nd seal member by the side of the inboard of a 2nd embodiment.

Hereinafter, embodiments of the hub unit bearing according to the present invention will be described in detail with reference to the drawings.

(First embodiment)
First, a first embodiment of a hub unit bearing according to the present invention will be described with reference to FIGS.

The hub unit bearing 10 of the present embodiment is a hub unit bearing for drive wheels, and as shown in FIG. 1, an outer ring member 11, a hub ring 12 that is an inner ring member, and an inner ring that is a separate body from the hub ring 12. A plurality of members, which are arranged in two rows so as to be rollable between the inner ring 13 integrally fixed to the hub wheel 12 and the inner diameter surface of the outer ring member 11 and the outer diameter surfaces of the hub wheel 12 and the inner ring 13. No. balls (rolling elements) 14, a pair of cages 15 respectively holding the two rows of balls 14 at equal intervals in the circumferential direction, an outer ring member 11 and an inner ring member (hub ring 12, inner ring 13). The first seal member 16 that closes the outboard side of the bearing internal space 10a and the second seal member 17 that closes the inboard side of the bearing internal space 10a. Note that the drawings are to be viewed in the direction of the reference numerals, the outboard side is the left side of each drawing that is the outer side in the width direction when assembled in an automobile, and the inboard side is the center side in the width direction. It is the right side of each figure.

On the inner diameter surface of the outer ring member 11, two rows of outer ring raceway surfaces 11a, 11a parallel to each other are formed separately. Inner ring raceway surfaces 12a and 13a are formed on the outer diameter surfaces of the hub wheel 12 and the inner ring 13 respectively corresponding to the outer ring raceway surfaces 11a and 11a of the outer ring member 11. A plurality of balls 14 rotatably held by a cage 15 are arranged at equal intervals in the circumferential direction on the two rows of raceways composed of the outer ring raceway surfaces 11a, 11a and the inner ring raceway surfaces 12a, 13a. There is.

The plurality of balls 14 contact each other with the outer ring raceway surfaces 11a, 11a and the inner ring raceway surfaces 12a, 13a at a contact angle of a back surface combination type (DB) to form a double-row angular ball bearing. As a result, the hub wheel 12 and the inner wheel 13 can rotate with respect to the outer wheel member 11.

A small-diameter step portion 12b is formed at an end portion of the hub wheel 12 on the inboard side. After the inner ring 13 is externally fitted to the small-diameter step portion 12b, the end portion of the small-diameter step portion 12b is caulked outward in the radial direction. By doing so, the inner ring 13 is fixed to the hub ring 12. Further, by pressing the inner ring 13 by caulking, an appropriate preload is applied.

The hub wheel 12 is a substantially columnar member, and a plate-shaped flange portion 12c extending outward in the radial direction from the outer diameter surface is formed at the end portion on the outboard side thereof. The flange portion 12c is provided with a plurality of hub bolts 12d for fastening a tire wheel, a brake rotor, and the like (not shown) at equal intervals in the circumferential direction.

As shown in FIG. 2, the first seal member 16 includes an annular core metal 20 press-fitted and fixed to the inner diameter surface of the outer ring member 11 at the end portion on the outboard side, and a rubber or elastomer fixed to the core metal 20. And an elastic seal portion 30.

The cored bar 20 is formed by subjecting a metal plate such as a steel plate to press working such as punching and bending, and the cylindrical portion 21 fixed to the inner diameter surface of the outer ring member 11 and the outboard of the cylindrical portion 21. It has an outer diameter flange portion 22 that extends radially outward from the side end portion, and an inner diameter flange portion 23 that is folded back from the inboard side end portion of the cylindrical portion 21 toward the outboard side and that extends radially inward. The cored bar 20 has its cylindrical portion 21 press-fitted and fixed to the inner peripheral surface of the outer ring member 11, and the side surface of the outer diameter flange portion 22 on the inboard side is elastically connected to the end surface of the outer ring member 11 on the outboard side. It abuts with a part of the seal portion 30 interposed.

The elastic seal portion 30 has first to third contact lips 31 to 33, one non-contact lip 34, one dam portion 35, and a covering portion 36.

The first contact lip 31 is formed so as to be inclined from the inner diameter side end portion of the inner diameter flange portion 23 of the cored bar 20 toward the inboard side and the radially inner side. The second contact lip 32 is formed to be inclined from the inner diameter side end portion of the inner diameter flange portion 23 of the cored bar 20 toward the outboard side and the radially outer side. The third contact lip 33 is provided on the outer side in the radial direction with respect to the second contact lip 32, and is formed to be inclined from the side surface of the inner diameter flange portion 23 of the cored bar 20 toward the outboard side and the outer side in the radial direction. The first to third contact lips 31 to 33 are formed over the entire circumference of the first seal member 16. The tip ends of the first to third contact lips 31 to 33 are in sliding contact with the outer diameter surface and the axial side surface of the hub wheel 12 over the entire circumference. In addition, the shape of the contact lip of each figure including the 1st-3rd contact lip 31-33 of FIG. 1 and FIG. 2 has shown the free state.

The non-contact lip 34 is provided radially outside the third contact lip 33, and is formed to be inclined from the outer diameter side end of the outer diameter flange portion 22 of the cored bar 20 toward the outboard side and the diameter outer side. Has been done. The non-contact lip 34 is formed over the entire circumference of the first seal member 16. The tip of the non-contact lip 34 closely opposes the inboard side surface of the flange portion 12c of the hub wheel 12 to form a labyrinth seal with the flange portion 12c.

The dam portion 35 is formed radially outward from the outer diameter side end portion of the outer diameter flange portion 22 of the cored bar 20. The dam portion 35 is formed so as to project radially outward from the outer diameter surface of the end portion on the outboard side of the outer ring member 11. The dam portion 35 is formed over the entire circumference of the first seal member 16. The side surface on the inboard side of the outer diameter flange portion 22 is abutted against the outboard side end surface of the outer ring member 11 with a part of the dam portion 35 interposed.

The covering portion 36 is formed so as to cover the side surface of the cored bar 20 on the outboard side. The covering portion 36 is formed over the entire circumference of the first seal member 16.

Then, as shown in FIG. 2, the outer diameter surface of the third contact lip 33, the inner diameter surface of the non-contact lip 34, and the outer board side surface of the covering portion 36 radially outside the third contact lip 33 are provided on the outer board side surface. , A plurality of protrusions 40 are formed. The plurality of protrusions 40 are vortex generators that turbulently generate the rotating airflow generated in the space S radially outside the third contact lip 33 when the hub wheel 12 that is the inner ring member rotates (when the vehicle is traveling). is there. That is, the plurality of protrusions 40 are provided on the outer diameter surface of the third contact lip 33 facing the space S radially outside the third contact lip 33, the inner diameter surface of the non-contact lip 34, and the outboard side of the covering portion 36. It is formed on the side surface.

The plurality of protrusions 40 formed on the third contact lip 33 are arranged in two rows at substantially equal intervals in a zigzag pattern over the entire circumference of the third contact lip 33. The plurality of protrusions 40 formed on the non-contact lip 34 are arranged in one row at substantially equal intervals over the entire circumference of the non-contact lip 34. The plurality of protrusions 40 formed on the covering portion 36 are arranged in two rows in a staggered manner at substantially equal intervals over the entire circumference of the covering portion 36. Further, in the covering portion 36, a plurality of protrusions 40 in two rows are formed at two positions on the side surface on the outboard side of the outer diameter flange portion 22 and the side surface on the outboard side of the inner diameter flange portion 23, respectively, in a radial direction. Has been done.

Then, the protrusion 40 serving as a vortex generator is formed in a partial spherical shape (substantially hemispherical shape). The shape of the protrusion 40 is not limited to the partial spherical shape (substantially hemispherical shape), and various shapes such as a cylindrical shape, a cylindrical shape, a polygonal pillar shape, and an embossed character can be selected. Further, the arrangement of the protrusions 40 is not limited to the form in which the plurality of protrusions 40 are formed at substantially equal intervals over the entire circumference. For example, a predetermined number (for example, three) of protrusions 40 is set as one group and a plurality of (for example, The four groups may be formed intermittently in the circumferential direction.

As shown in FIG. 3, the second seal member 17 includes an annular core metal 50 that is press-fitted and fixed to the inner diameter surface of the inboard side end of the outer ring member 11, and rubber or elastomer that is fixed to the core metal 50. And an elastic seal portion 60.

The cored bar 50 is formed by subjecting a metal plate such as a steel plate to press working such as punching and bending, and the cylindrical portion 51 fixed to the inner diameter surface of the outer ring member 11 and the outboard of the cylindrical portion 51. And a flange portion 52 that extends radially inward from the side end portion.

The elastic seal portion 60 has first to third contact lips 61 to 63 and a covering portion 64.

The first contact lip 61 is formed so as to be inclined from the inner diameter side end of the flange 52 of the core metal 50 toward the outboard side and the inner side in the radial direction. The second contact lip 62 is formed so as to be inclined from the inner diameter side end of the flange portion 52 of the core metal 50 toward the inboard side and the inner side in the radial direction. The third contact lip 63 is provided radially outward of the second contact lip 62, and is formed to incline from the side surface of the flange portion 52 of the cored bar 50 toward the inboard side and radially outward. The first to third contact lips 61 to 63 are formed over the entire circumference of the second seal member 17. The tip end portions of the first to third contact lips 61 to 63 are in sliding contact with the outer diameter surface and the axial side surface of the slinger 70 fixed to the outer diameter surface of the inner ring 13 over the entire circumference.

The slinger 70 is formed by subjecting a metal plate such as a steel plate to press working such as punching and bending, and the cylindrical portion 71 fixed to the outer diameter surface of the inner ring 13 and the inboard side of the cylindrical portion 71. It has a collar portion 72 that extends radially outward from the end portion, and a magnetic encoder 73 that is attached to the side surface of the collar portion 72 on the inboard side. The slinger 70 constitutes a part of the inner ring 13 which is the inner ring member.

The covering portion 64 is formed so as to cover the side surface of the cored bar 50 on the inboard side. The covering portion 64 is formed over the entire circumference of the second seal member 17.

Then, as shown in FIG. 3, a plurality of protrusions 40 are formed on the outer diameter surface of the third contact lip 63 and on the inboard side surface of the covering portion 64 radially outside the third contact lip 63. ing. Then, the plurality of protrusions 40 turbulence the rotating airflow generated in the space S radially outside the third contact lip 63 when the inner ring 13 (slinger 70) that is the inner ring member rotates (during vehicle traveling). It is a vortex generator. That is, the plurality of protrusions 40 are formed on the radially outer surface of the third contact lip 63 facing the space S radially outside the third contact lip 63 and the inboard side surface of the covering portion 64.

The plurality of protrusions 40 formed on the third contact lip 63 are arranged in two rows in a staggered manner at substantially equal intervals over the entire circumference of the third contact lip 63. The plurality of protrusions 40 formed on the covering portion 64 are arranged in one row at substantially equal intervals over the entire circumference of the covering portion 64 that covers the side surface of the collar portion 52 on the inboard side. Further, in the covering portion 64, two rows of the plurality of protrusions 40 in a row are formed so as to be separated from each other in the radial direction.

As described above, according to the hub unit bearing 10 of the present embodiment, the third contact lip 33 of the first seal member 16, the non-contact lip 34, and the covering portion 36 radially outside of the third contact lip 33. The plurality of protrusions 40 serving as vortex generators formed on the outer peripheral surface can turbulently rotate the rotating airflow generated in the space S radially outside the third contact lip 33 when the hub wheel 12 that is the inner ring member rotates. .. Therefore, the laminarization of the rotating airflow in the space S prevents the waterdrops from being taken into the vicinity of the portion where the airflow is the fastest and rotating, so that the waterdrops entering the space S are exposed to the outside (the outer ring member 11). Can be discharged to the outer diameter surface side). Therefore, since it is possible to prevent the water droplets from adhering to the sliding contacts of the first to third contact lips 31 to 33, deterioration of the lubrication state of the first to third contact lips 31 to 33 and the sliding contact surface. It is possible to prevent the generation of rust and improve the life of the seal.

Further, according to the hub unit bearing 10 of the present embodiment, a plurality of vortex generators are formed on the third contact lip 63 of the second seal member 17 and the covering portion 64 radially outward of the third contact lip 63. By the protrusion 40, the rotating airflow generated in the space S radially outside the third contact lip 63 when the inner ring 13 (slinger 70) which is the inner ring member rotates can be made turbulent. Therefore, the laminarization of the rotating airflow in the space S prevents the waterdrops from being taken into the vicinity of the portion with the fastest airflow and rotating, and the waterdrops entering the space S are exposed to the outside (from the slinger 70). Can also be discharged to the inboard side). Therefore, since it is possible to prevent the water droplets from adhering to the sliding contacts of the first to third contact lips 61 to 63, deterioration of the lubrication state of the first to third contact lips 61 to 63 and the sliding contact surface. It is possible to prevent the generation of rust and improve the life of the seal.

Next, as a modified example of the present embodiment, as shown in FIG. 4, a first seal member 16B may be used instead of the first seal member 16. The first seal member 16B includes an annular core metal 80 press-fitted and fixed to the inner diameter surface of the outer ring member 11 on the outboard side end, and an elastic seal member 90 fixed to the core metal 80 and made of rubber or elastomer. , Is provided.

The cored bar 80 is formed by subjecting a metal plate such as a steel plate to press working such as punching and bending, and the cylindrical portion 81 fixed to the inner diameter surface of the outer ring member 11 and the outboard of the cylindrical portion 81. A flange portion 82 that is folded back from the side end portion toward the inboard side and extends radially inward.

The elastic seal portion 90 has first to third contact lips 91 to 93 and a covering portion 94.

The first contact lip 91 is formed to incline from the inner diameter side end of the flange portion 82 of the cored bar 80 toward the inboard side and the radially inner side. The second contact lip 92 is formed so as to be inclined from the inner diameter side end portion of the flange portion 82 of the core metal 80 toward the outboard side and the radially inner side. The third contact lip 93 is provided radially outward of the second contact lip 92, and is formed so as to be inclined from the side surface of the flange portion 82 of the cored bar 80 toward the outboard side and radially outward. The first to third contact lips 91 to 93 are formed over the entire circumference of the first seal member 16B. The tip ends of the first to third contact lips 91 to 93 are in sliding contact with the outer diameter surface and the axial side surface of the hub wheel 12 over the entire circumference.

The covering portion 94 is formed so as to cover the side surface of the cored bar 80 on the outboard side. The covering portion 94 is formed over the entire circumference of the first seal member 16B.

Then, as shown in FIG. 4, a plurality of protrusions 40 are formed on the outer diameter surface of the third contact lip 93 and the outer board side surface of the covering portion 94 radially outside the third contact lip 93. ing. The plurality of protrusions 40 are vortex generators that turbulently rotate the rotating airflow generated in the space S radially outside the third contact lip 93 when the hub wheel 12 that is the inner ring member rotates (when the vehicle is traveling). is there. That is, the plurality of protrusions 40 are formed on the outer diameter surface of the third contact lip 93 facing the space S radially outside the third contact lip 93 and the side surface of the covering portion 94 on the outboard side.

The plurality of protrusions 40 formed on the third contact lip 93 are arranged in two rows at substantially equal intervals in a zigzag pattern over the entire circumference of the third contact lip 93. The plurality of protrusions 40 formed on the covering portion 94 are arranged in two rows in a staggered manner at substantially equal intervals over the entire circumference of the covering portion 94.

According to this modification, the inner ring member includes the third contact lip 93 of the first seal member 16</b>B and the plurality of protrusions 40 serving as a vortex generator formed on the covering portion 94 radially outward of the third contact lip 93. The rotating airflow generated in the space S radially outside the third contact lip 93 when the hub wheel 12 is rotated can be made turbulent. Therefore, the laminarization of the rotating airflow in the space S prevents the waterdrops from being taken into the vicinity of the portion where the airflow is the fastest and rotating, so that the waterdrops entering the space S are exposed to the outside (the outer ring member 11). Can be discharged to the outer diameter surface side). Therefore, since it is possible to prevent the water droplets from adhering to the sliding contacts of the first to third contact lips 91 to 93, deterioration of the lubrication state of the first to third contact lips 91 to 93 and the sliding contact surface. It is possible to prevent the generation of rust and improve the life of the seal.

(Second embodiment)
Next, a second embodiment of the hub unit bearing according to the present invention will be described with reference to FIGS. 5 and 6. In addition, about the same or equivalent part as the said 1st Embodiment, the same code|symbol is attached|subjected to drawing and the description is abbreviate|omitted or simplified.

In the present embodiment, as shown in FIG. 5, a first seal member 16C is used instead of the first seal member 16B of the modified example of the first embodiment described above. The first seal member 16C has the same configuration as the first seal member 16B except for the positions where the plurality of protrusions 40 are formed.

In the first seal member 16C, a plurality of protrusions 40 are formed on the side surface of the first contact lip 91 on the outboard side and the inner diameter surface of the second contact lip 92. The plurality of protrusions 40 turbulently rotate the rotating airflow generated in the space S1 between the first contact lip 91 and the second contact lip 92 when the hub wheel 12 that is the inner ring member rotates (when the vehicle is traveling). It is a vortex generator that transforms. That is, the plurality of protrusions 40 are formed on the side surface on the outboard side of the first contact lip 91 facing the space S1 between the first contact lip 91 and the second contact lip 92, and the inner diameter surface of the second contact lip 92. Has been formed.

The plurality of protrusions 40 formed on the first contact lip 91 are arranged in one row at substantially equal intervals over the entire circumference of the first contact lip 91. The plurality of protrusions 40 formed on the inner diameter surface of the second contact lip 92 are arranged in two rows in a zigzag manner at substantially equal intervals over the entire circumference of the second contact lip 92.

Further, in the first seal member 16C, the outer diameter surface of the second contact lip 92, the inner diameter surface of the third contact lip 93, and the outboard of the covering portion 94 between the second contact lip 92 and the third contact lip 93. A plurality of protrusions 40 are formed on the side surface on the side. Then, the plurality of protrusions 40 turbulently rotate the rotating airflow generated in the space S2 between the second contact lip 92 and the third contact lip 93 when the hub wheel 12 that is the inner ring member rotates (when the vehicle is traveling). It is a vortex generator that transforms. That is, the plurality of protrusions 40 include the outer diameter surface of the second contact lip 92 facing the space S2 between the second contact lip 92 and the third contact lip 93, the inner diameter surface of the third contact lip 93, and the covering portion. It is formed on the side surface of the 94 on the outboard side.

The plurality of protrusions 40 formed on the outer diameter surface of the second contact lip 92 are arranged in three rows in a staggered manner at substantially equal intervals over the entire circumference of the second contact lip 92. The plurality of protrusions 40 formed on the third contact lip 93 are arranged in a staggered manner in eight rows at substantially equal intervals over the entire circumference of the third contact lip 93. Further, the plurality of projections 40 in eight rows are arranged continuously from the inner diameter surface of the third contact lip 93 to the covering portion 94. The plurality of protrusions 40 formed on the covering portion 94 between the second contact lip 92 and the third contact lip 93 are arranged in one row at substantially equal intervals over the entire circumference of the covering portion 94.

Further, in the present embodiment, as shown in FIG. 6, a second seal member 17B is used instead of the second seal member 17 of the first embodiment described above. The second seal member 17B has the same configuration as the second seal member 17 except the positions where the plurality of protrusions 40 are formed.

In the second seal member 17B, a plurality of protrusions 40 are formed on the inboard side surface of the first contact lip 61 and the inner diameter surface of the second contact lip 62. The plurality of protrusions 40 are the rotational airflow generated in the space S1 between the first contact lip 61 and the second contact lip 62 when the inner ring 13 (slinger 70) that is the inner ring member rotates (when the vehicle is traveling). Is a vortex generator that makes turbulence. That is, the plurality of protrusions 40 are formed on the inboard side surface of the first contact lip 61 facing the space S1 between the first contact lip 61 and the second contact lip 62 and the inner diameter surface of the second contact lip 62. Has been formed.

The plurality of protrusions 40 formed on the first contact lip 61 are arranged in one row at substantially equal intervals over the entire circumference of the first contact lip 61. The plurality of protrusions 40 formed on the inner diameter surface of the second contact lip 62 are arranged in one row at substantially equal intervals over the entire circumference of the second contact lip 62.

Further, in the second seal member 17B, a plurality of protrusions 40 are formed on the inboard side end surface of the second contact lip 62 and the inner diameter surface of the third contact lip 63. The plurality of protrusions 40 are the rotational airflow generated in the space S2 between the second contact lip 62 and the third contact lip 63 when the inner ring 13 (slinger 70) that is the inner ring member rotates (during vehicle traveling). Is a vortex generator that makes turbulence. That is, the plurality of protrusions 40 are formed on the inboard side end surface of the second contact lip 62 facing the space S2 between the second contact lip 62 and the third contact lip 63 and the inner diameter surface of the third contact lip 63. Has been done.

The plurality of protrusions 40 formed on the end surface of the second contact lip 62 on the inboard side are arranged in one row at substantially equal intervals over the entire circumference of the second contact lip 62. The plurality of protrusions 40 formed on the third contact lip 63 are arranged in two rows in a staggered manner at substantially equal intervals over the entire circumference of the third contact lip 63.

As described above, according to the hub unit bearing 10 of the present embodiment, between the first to third contact lips 91 to 93 of the first seal member 16C and between the second contact lip 92 and the third contact lip 93. Due to the plurality of protrusions 40 serving as vortex generators formed on the coating portion 94 of the rotating airflow generated in the spaces S1 and S2 between the first to third contact lips 91 to 93 when the hub wheel 12 that is the inner ring member rotates. Can be turbulent. Therefore, the pressure drop in the spaces S1 and S2 can be prevented, so that the first to third contact lips 91 to 93 can be prevented from sticking to the sliding contact surface. Therefore, it is possible to prevent the first to third contact lips 91 to 93 from sticking to the sliding contact surface, and thus prevent the first to third contact lips 91 to 93 from being worn and the bearing torque from increasing. You can

Further, according to the hub unit bearing 10 of the present embodiment, the inner ring 13 that is the inner ring member is formed by the plurality of projections 40 that are vortex generators formed on the first to third contact lips 61 to 63 of the second seal member 17B. When the (slinger 70) rotates, the rotating airflow generated in the spaces S1 and S2 between the first to third contact lips 61 to 63 can be made turbulent. Therefore, the pressure drop in the spaces S1 and S2 can be prevented, so that the first to third contact lips 61 to 63 can be prevented from sticking to the sliding contact surfaces. Therefore, it is possible to prevent the first to third contact lips 61 to 63 from sticking to the sliding contact surfaces, and thus prevent the first to third contact lips 61 to 63 from being worn and the bearing torque from increasing. You can
Other configurations and operational effects are the same as those in the first embodiment.

(Third Embodiment)
Next, a third embodiment of the hub unit bearing according to the present invention will be described with reference to FIGS. 7 and 8. In addition, about the same or equivalent part as the said 1st and 2nd embodiment, the same code|symbol is attached|subjected to drawing and the description is abbreviate|omitted or simplified.

In the present embodiment, as shown in FIG. 7, a first seal member 16D is used instead of the first seal member 16C of the second embodiment described above. The first seal member 16D has the same configuration as that of the first seal member 16C except the formation positions of the plurality of protrusions 40 and the angle of intersection between the contact lip and the sliding contact surface.

In the first seal member 16D, the plurality of protrusions 40 formed on the side surface of the first contact lip 91 on the outboard side are arranged in one row at substantially equal intervals over the entire circumference of the first contact lip 91. ing. The plurality of protrusions 40 formed on the inner diameter surface of the second contact lip 92 are arranged in two rows in a zigzag manner at substantially equal intervals over the entire circumference of the second contact lip 92.

In addition, in the first seal member 16D, the plurality of protrusions 40 formed on the outer diameter surface of the second contact lip 92 are arranged in two rows in a staggered manner at substantially equal intervals over the entire circumference of the second contact lip 92. Has been done. The plurality of protrusions 40 formed on the inner diameter surface of the third contact lip 93 are arranged in a zigzag pattern in nine rows at substantially equal intervals over the entire circumference of the third contact lip 93. The plurality of projections 40 in nine rows are continuously arranged from the inner diameter surface of the third contact lip 93 to the covering portion 94. Further, in the present embodiment, the plurality of protrusions 40 are not formed on the covering portion 94 between the second contact lip 92 and the third contact lip 93.

Furthermore, in the first seal member 16D, the intersecting angles θ1 to θ3 between the first to third contact lips 91 to 93 and the sliding contact surface of the hub wheel 12 are larger than those in the first seal member 16C of the second embodiment described above. The spaces S1 and S2 between the first to third contact lips 91 to 93 are widened.

Further, in the present embodiment, as shown in FIG. 8, a second seal member 17C is used instead of the second seal member 17B of the second embodiment described above. The second seal member 17C has the same configuration as the second seal member 17B except for the positions where the plurality of protrusions 40 are formed and the angle of intersection between the contact lip and the sliding contact surface.

In the second seal member 17C, the plurality of protrusions 40 formed on the inboard side surface of the first contact lip 61 are staggered in two rows at substantially equal intervals over the entire circumference of the first contact lip 61. It is located in. The plurality of protrusions 40 formed on the inner diameter surface of the second contact lip 62 are arranged in two rows in a zigzag manner at substantially equal intervals over the entire circumference of the second contact lip 62.

Further, in the second seal member 17C, the plurality of protrusions 40 formed on the outer diameter surface of the second contact lip 62 are arranged in two rows in a zigzag pattern at substantially equal intervals over the entire circumference of the second contact lip 62. Has been done. The plurality of protrusions 40 formed on the inner diameter surface of the third contact lip 63 are arranged in zigzag in three rows at substantially equal intervals over the entire circumference of the third contact lip 63.

Further, in the second seal member 17C, the intersecting angles θ1 to θ3 between the first to third contact lips 61 to 63 and the slidable contact surface of the slinger 70 are made larger than those in the second seal member 17B of the second embodiment described above. Thus, the spaces S1 and S2 between the first to third contact lips 61 to 63 are widened.

As described above, according to the hub unit bearing 10 of the present embodiment, the intersection angles θ1 to θ3 between the first to third contact lips 91 to 93 of the first seal member 16D and the sliding contact surface of the hub wheel 12 are increased. Then, in order to widen the spaces S1 and S2 between the first to third contact lips 91 to 93, the rotating airflow generated in the spaces S1 and S2 is generated in the vicinity of the sliding contacts of the first to third contact lips 91 to 93. Can be turbulent up to. Therefore, the pressure drop in the spaces S1 and S2 can be further prevented, so that the first to third contact lips 91 to 93 can be further prevented from sticking to the sliding contact surface.

Further, according to the hub unit bearing 10 of the present embodiment, the intersection angles θ1 to θ3 between the first to third contact lips 61 to 63 of the second seal member 17C and the slidable contact surface of the slinger 70 are increased to increase the first angle. ~ In order to widen the spaces S1 and S2 between the third contact lips 61 to 63, the rotating airflow generated in these spaces S1 and S2 is made turbulent to the vicinity of the sliding contact points of the first to third contact lips 61 to 63. be able to. Therefore, the pressure drop in the spaces S1 and S2 can be further prevented, so that the first to third contact lips 61 to 63 can be further prevented from sticking to the sliding contact surface.
Other configurations and operational effects are the same as those of the first and second embodiments.

It should be noted that the present invention is not limited to the examples illustrated in the above embodiments, and can be appropriately changed without departing from the scope of the present invention.
For example, in the first seal member and the second seal member, the angle of intersection between the plurality of protrusions of the first embodiment, the plurality of protrusions of the second embodiment, and the contact lip and the sliding contact surface of the third embodiment. There is no restriction on the combination of increasing and.
Further, in the case of the first embodiment, the non-contact lip of the first seal member may be omitted.
Further, in the case of the first embodiment, the plurality of protrusions may be formed on only one of the third contact lip and the covering portion.
Further, in the case of the second and third embodiments, the plurality of protrusions may be formed only on one of the first to third contact lips and the covering portion.
In addition, in the case of the second and third embodiments, the plurality of protrusions are formed only on one of the first contact lip and the second contact lip and also formed on only one of the second contact lip and the third contact lip. It may have been done.
Further, the hub unit bearing is not limited to the hub unit bearing for the drive wheel shown in FIG. 1 and may be a hub unit bearing for the driven wheel.

10 hub unit bearing 10a bearing internal space 11 outer ring member 11a outer ring raceway surface 12 hub ring (inner ring member)
12a Inner ring raceway surface 12c Flange portion 13 Inner ring (inner ring member)
13a inner raceway surface 14 balls (rolling elements)
15 Retainer 16, 16B, 16C, 16D 1st seal member 17, 17B, 17C 2nd seal member 20 Core metal 21 Cylindrical part 22 Outer diameter flange part 23 Inner diameter flange part 30 Elastic seal part 31 1st contact lip 32 2nd Contact lip 33 Third contact lip 34 Non-contact lip 35 Weir part 36 Cover part 40 Protrusion (vortex generator)
50 Core metal 51 Cylindrical part 52 Collar part 60 Elastic seal part 61 1st contact lip 62 2nd contact lip 63 3rd contact lip 64 Cover part 70 Slinger 71 Cylindrical part 72 Collar part 80 Core metal 81 Cylindrical part 82 Collar part 90 Elastic Seal portion 91 First contact lip 92 Second contact lip 93 Third contact lip 94 Cover portion S Space radially outside contact lip S1 Space between contact lips S2 Space between contact lips

Claims (7)

An outer ring member, an inner ring member rotatably provided with respect to the outer ring member via a plurality of rolling elements, a retainer that holds the plurality of rolling elements at substantially equal intervals in the circumferential direction, the outer ring member and the A hub unit bearing comprising: a seal member for closing at least one of an outboard side and an inboard side of a bearing internal space between the inner ring member and the inner ring member,
The seal member includes an annular core metal fixed to the inner diameter surface of the outer ring member, and an elastic seal portion fixed to the core metal,
The elastic seal portion is formed on the inner diameter side of the core metal, and has at least one contact lip slidably contacting the inner ring member, and a coating portion formed to cover a side surface of the core metal,
A hub unit bearing, wherein a plurality of protrusions are formed on at least one of the at least one contact lip and the covering portion radially outside of the at least one contact lip. The elastic seal portion further has a non-contact lip provided radially outward of the at least one contact lip.
The hub unit bearing according to claim 1, wherein the plurality of protrusions are formed on the non-contact lip. The plurality of protrusions are formed on the at least one contact lip, the non-contact lip, and the covering portion facing a space radially outside of the at least one contact lip. Hub unit bearing. The plurality of protrusions are vortex generators that turbulently generate a rotating airflow generated in a space radially outside the at least one contact lip when the inner ring member rotates. The hub unit bearing according to claim 1. An outer ring member, an inner ring member rotatably provided with respect to the outer ring member via a plurality of rolling elements, a retainer that holds the plurality of rolling elements at substantially equal intervals in the circumferential direction, the outer ring member and the A hub unit bearing comprising: a seal member for closing at least one of an outboard side and an inboard side of a bearing internal space between the inner ring member and the inner ring member,
The seal member includes an annular core metal fixed to the inner diameter surface of the outer ring member, and an elastic seal portion fixed to the core metal,
The elastic seal portion is formed on the inner diameter side of the core metal, and has a plurality of contact lips that slidably contact the inner ring member, and a coating portion formed to cover a side surface of the core metal,
A hub unit bearing, wherein a plurality of protrusions are formed on at least one of the plurality of contact lips and the covering portion between the plurality of contact lips. The hub unit bearing according to claim 5, wherein the plurality of protrusions are formed on the plurality of contact lips and the covering portion facing a space between the plurality of contact lips. The hub unit according to claim 5 or 6, wherein the plurality of protrusions are vortex generators that turbulently generate a rotating airflow generated in a space between the plurality of contact lips when the inner ring member rotates. bearing.

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