JP7495277B2 - Wheel support rolling bearing unit - Google Patents

Description

The present invention relates to a wheel-supporting rolling bearing unit, and in particular to a wheel-supporting rolling bearing unit equipped with a combination seal ring.

Wheel support rolling bearing units are used in a muddy water environment, so they require a seal with good muddy water resistance to seal the end opening between the outer diameter side member and the inner diameter side member that rotate relative to each other. As such a seal, a combination seal ring is used that includes a seal ring having a core metal and a sealing material, and a slinger.

Patent Document 1 describes a wheel bearing device that provides improved sealing performance while suppressing an increase in the rotational torque of the seal by providing an inclined surface at the tip of the upright portion of the slinger, and a seal plate (corresponding to the seal ring in this application) that is provided with a radial lip that slides against the inclined surface of the slinger, two side lips that slide against the upright portion of the slinger, and a labyrinth seal that faces the cylindrical portion of the slinger with a small radial gap between them.

JP 2007-100844 A

However, in the case of a combination seal ring in which the side lip is only in sliding contact with the slinger, the seal ring and slinger tend to separate during transportation from the seal factory or when supplied to the distribution device of the assembly machine at the bearing factory, making them difficult to handle. Also, if the seal ring and slinger become misaligned, they cannot be pressed in at the same time, which means that the seal press-in process becomes a two-step process, which can lead to increased equipment and assembly costs.

The vehicle bearing device described in Patent Document 1 uses the radial lip of the seal plate to press the inclined surface of the slinger from the outside, preventing the seal plate and the slinger from being separated. However, friction torque is also generated between the radial lip and the inclined surface of the slinger, which is likely to impair low torque performance, leaving room for further improvement.

The present invention was made in consideration of the above-mentioned problems, and its purpose is to provide a wheel support rolling bearing unit that ensures high sealing performance while suppressing an increase in rotational torque caused by the seal ring, and in which the seal ring and the slinger will not separate even when the combined seal ring is in a stand-alone state.

The above object of the present invention can be achieved by the following configuration.
(1) An outer diameter side member having a double row outer ring raceway on its inner circumferential surface and not rotating even during use;
an inner diameter side member having a double row inner ring raceway on an outer circumferential surface thereof and rotating together with a wheel during use;
a plurality of rolling elements provided between each of the outer ring raceways and each of the inner ring raceways in a rollable manner;
a combination seal ring including a slinger having a substantially L-shaped cross section and a seal ring disposed axially opposite the slinger, the combination seal ring being assembled to the outer diameter side member and the inner diameter side member to seal between the outer diameter side member and the inner diameter side member;
A wheel supporting rolling bearing unit comprising:
The slinger includes an inner diameter side cylindrical portion that is fitted onto the inner diameter side member, and an outer ring portion that extends radially outward from one axial end side of the inner diameter side cylindrical portion,
The seal ring is
a core bar having an outer diameter side cylindrical portion provided on an outer peripheral surface at one axial end side thereof and fitted into the outer diameter side member, and an inner annular portion extending radially inward from the other axial end side of the outer diameter side cylindrical portion;
a seal member fixed to the inner circular ring portion of the core metal and having a plurality of lips that are in sliding contact with the other end side surface of the outer circular ring portion of the slinger;
a gasket portion fixed to the small diameter portion of the outer diameter side cylindrical portion of the core, having an outer diameter larger than the outer diameter of the outer diameter side cylindrical portion, and elastically fitting with an inner peripheral surface of the outer diameter side member; a protrusion extending from the outer diameter side cylindrical portion of the core to one axial end side, and a nose gasket portion extending radially inward from one axial end portion of the protrusion and having a locking lip disposed opposite one end side surface of the outer circular ring portion of the slinger or one end side surface of an encoder fixed to the slinger;
Equipped with
the gasket portion has an overlapping portion located on the other end side and overlapping with the small diameter portion of the core in the radial direction, and a non-overlapping portion located on the one end side and not overlapping with the small diameter portion of the core in the radial direction,
When the combined seal ring is press-fitted between the outer diameter side member and the inner diameter side member and assembled, a portion on one axial end side on the outer diameter side of the overlapping portion moves toward the one axial end side, the non-overlapping portion moves radially inward, and the protruding portion also moves radially inward following the non-overlapping portion, so that the locking lip deforms into an arc shape that convex toward the other axial end side, thereby forming a non-contact lip.
Rolling bearing unit for wheel support.

According to the wheel support rolling bearing unit of the present invention, after the combined seal ring is assembled, the locking lip deforms to form a non-contact lip, ensuring high sealing performance while suppressing an increase in rotational torque caused by the seal. In addition, even when the combined seal ring is in a stand-alone state, the slinger and seal ring do not separate, making the combined seal ring easy to handle.

1 is a cross-sectional view of a main portion of a wheel supporting rolling bearing unit according to a first embodiment of the present invention; 2 is a cross-sectional view showing the positional relationship when each part of the combined seal ring shown in FIG. 1 before assembly is disposed in a regular assembly position after assembly. FIG. 3 is a cross-sectional view of a main portion showing a state before the combination seal ring shown in FIG. 2 is assembled. 3 is a cross-sectional view of a main portion showing a state after the combination seal ring shown in FIG. 2 has been assembled. 11 is a cross-sectional view showing the positional relationship of components of a combination seal ring according to a second embodiment of the present invention before assembly when the components are arranged in their normal assembly positions after assembly. FIG. 13 is a cross-sectional view showing the positional relationship of components of a combination seal ring according to a third embodiment of the present invention before assembly when the components are arranged in their normal assembly positions after assembly. FIG. 13 is a cross-sectional view showing the positional relationship of components of a combination seal ring according to a fourth embodiment of the present invention before assembly when the components are arranged in their normal assembly positions after assembly. FIG. 13 is a cross-sectional view showing the positional relationship of components of a combined seal ring according to a fifth embodiment of the present invention before assembly when the components are arranged in their normal assembly positions after assembly. FIG.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Wheel supporting rolling bearing units according to embodiments of the present invention will be described in detail below with reference to the drawings.
Furthermore, "outboard" with respect to the axial direction of the wheel supporting rolling bearing unit 10 refers to the left side in Fig. 1, which is the outer side of the vehicle body when the wheel supporting rolling bearing unit 10 is assembled to the vehicle. Conversely, the right side in Fig. 1, which is the center side of the vehicle body when the wheel supporting rolling bearing unit 10 is assembled to the vehicle, is called "inboard".
2 to 8, which is the outer side of the wheel supporting rolling bearing unit 10 when the combined seal rings 20, 20A to 20D are assembled to the wheel supporting rolling bearing unit 10. Conversely, the left side of the combined seal rings 20, 20A to 20D in the axial direction thereof, which is the inner side of the wheel supporting rolling bearing unit 10 when the combined seal rings 20, 20A to 20D are assembled to the wheel supporting rolling bearing unit 10, is referred to as the "other end side."

First Embodiment
As shown in Figure 1, the wheel support rolling bearing unit 10 of this embodiment comprises an outer diameter side member 11, a hub wheel 12 which is an inner diameter side member, an inner ring 13 which is an inner diameter side member separate from the hub wheel 12 and is fixed integrally to the hub wheel 12, a plurality of balls (rolling elements) 14 arranged in two rows so as to be rollable between the outer peripheral surfaces of the hub wheel 12 and the inner ring 13 and the inner peripheral surface of the outer diameter side member 11, a pair of retainers 16 which hold the two rows of balls 14 at approximately equal intervals in the circumferential direction, and a seal ring 19 and a combination seal ring 20 which seal both end openings of the bearing internal space 10a.

The hub wheel 12 is a generally cylindrical member, and its outboard end (left side in the figure) is formed with a flange portion 12b that extends radially outward from the outer circumferential surface. A plurality of hub bolts 17 for fastening a tire wheel and a brake rotor (not shown) are provided at generally equal intervals in the circumferential direction on the flange portion 12b.

A small diameter step 12c is formed on the inboard end (right side in the figure) of the hub wheel 12. After the inner ring 13 is fitted onto this small diameter step 12c, the end of the small diameter step 12c is crimped radially outward, thereby fixing the inner ring 13 to the hub wheel 12. In addition, the inner ring 13 is pressed by the crimping process, thereby applying an appropriate preload.

Two parallel rows of outer ring raceways 11a, 11a are formed at a distance from each other on the inner peripheral surface of the outer diameter side member 11. In addition, inner ring raceways 12a, 13a are formed on the outer peripheral surfaces of the hub ring 12 and the inner ring 13, respectively, corresponding to the outer ring raceways 11a, 11a of the outer diameter side member 11. A plurality of balls 14, which are held rotatably by a cage 16, are arranged at equal intervals in the circumferential direction on the two rows of raceways formed by the inner ring raceways 12a, 13a and the outer ring raceways 11a, 11a.

The balls 14 are arranged in a back-to-back combination, contacting the outer ring raceways 11a, 11a and the inner ring raceways 12a, 13a at a predetermined contact angle. This allows the hub ring 12 and the inner ring 13 to rotate relative to the outer diameter side member 11.

Next, the combination seal ring 20 according to the first embodiment will be described in detail with reference to Figures 2 to 4. As shown in Figure 2, the combination seal ring 20 includes a slinger 30 and a seal ring 40, which are assembled and positioned axially opposite each other.

The slinger 30 has an inner diameter side cylindrical portion 31 that fits onto the inner ring 13, which is the inner diameter side member of the wheel support rolling bearing unit 10, and an outer circular ring portion 32 that is bent and extended radially outward from one axial end side (the right end edge in FIG. 2) of the inner diameter side cylindrical portion 31, and has an L-shaped cross section and an annular shape as a whole. The slinger 30 is formed as a single piece by punching out a metal plate having excellent corrosion resistance, such as a galvanized steel plate or a stainless steel plate, using a press machine and bending processes such as burring.

The encoder 34, which is made of magnetic rubber with ferrite powder mixed in it and formed into a ring shape, is bonded and fixed to the outer surface 32a of one axial end of the outer ring portion 32 (right side in Fig. 2) by vulcanization molding or the like. On the axial side of the encoder 34, S poles and N poles are arranged alternately and at equal intervals in the circumferential direction. On the outer diameter side, the encoder 34 extends beyond the outer diameter edge 32b of the outer ring portion 32 and reaches the other end of the outer ring portion 32. On the inner diameter side, the encoder 34 has an inner diameter lip 38 that extends radially inward and seals the fitting portion between the inner diameter side cylindrical portion 31 and the inner ring 13.

The seal ring 40 comprises a metal core 41, and a seal member 51 and a nose gasket portion 61 made of an elastic material such as a rubber-like elastomer, each of which is fixed to the core 41 by vulcanization molding or the like.

The core metal 41 has an outer diameter side cylindrical portion 42 that fits inside the outer diameter side member 11 of the rolling bearing unit 10, and an inner ring portion 43 that is bent and extended radially inward from the other axial end side of the outer diameter side cylindrical portion 42, and has a generally L-shaped cross section and an annular shape as a whole. The outer peripheral surface of one axial end side of the outer diameter side cylindrical portion 42 is provided with a small diameter portion 44 that has a diameter smaller than the outer diameter of the outer diameter side cylindrical portion 42. The core metal 41 is integrally formed by punching a metal plate such as a low carbon steel plate or a stainless steel plate with a press machine and bending such as burring.

The seal member 51 comprises a base 55 fixed to cover both side surfaces 43a, 43b and the inner peripheral edge 43c of the inner circular ring portion 43 of the core metal 41, two sliding lips 52, 53 extending obliquely upward in the axial direction from the base 55 toward the slinger 30, and one grease lip 54 extending radially inward from the base 55.

When the slinger 30 and the seal ring 40 are assembled in an axially opposed arrangement, the leading edges of the two sliding lips 52, 53 of the seal member 51 are in sliding contact with the other end side of the outer circular ring portion 32 of the slinger 30, and the leading edge of one grease lip 54 is in sliding contact with the outer peripheral surface of the inner diameter side cylindrical portion 31 with a slight interference or is arranged with a slight gap.

The nose gasket portion 61 is formed in a substantially cylindrical shape with a gasket portion 62, a protruding portion 63, and a locking lip 64. The gasket portion 62 has an outer diameter larger than the outer diameter of the outer diameter side cylindrical portion 42, and has an overlapping portion 62a at the other end side that overlaps radially with the small diameter portion 44, and a non-overlapping portion 62b at one end side that does not overlap radially with the small diameter portion 44. The gasket portion 62 seals the fitting surface between the core metal 41 and the outer diameter side member 11 by elastically fitting with the inner peripheral surface of the outer diameter side member 11. The protruding portion 63 is formed by extending from the outer diameter side cylindrical portion 42 of the core metal 41 to one end side in the axial direction, and the locking lip 64 is extended radially inward from one axial end of the protruding portion 63 and is disposed opposite one end side surface 34a of the encoder 34. The outer diameter corner of one end side surface 34a of the encoder 34, which faces the locking lip 64, is chamfered to form an inclined surface 39.

The nose gasket portion 61 is fixed to the outer peripheral surface of the small diameter portion 44 of the outer diameter side cylindrical portion 42 by vulcanization molding or the like, but the end surface 44a of the small diameter portion 44 is a fractured surface caused by punching, so the adhesive does not adhere well to it, and the adhesive strength is weak or it is not bonded at all.

The combined seal ring 20, which is constructed by combining the slinger 30 and the seal ring 40 in the axial direction as described above, is unitized by preventing separation of the slinger 30 and the seal ring 40. That is, the locking lip 64 overlaps with one end side surface 34a of the encoder 34 in the axial direction at one axial end side of the encoder 34. As shown in Fig. 3, even if the slinger 30 attempts to displace in a direction away from the seal ring 40, the locking lip 64 and one end side surface 34a of the encoder 34 engage with each other to prevent this displacement. That is, the locking lip 64 and the encoder 34 constitute a locking mechanism that prevents separation of the slinger 30 and the seal ring 40.
In addition, since the grease lip 54 of the sealing member 51 is in sliding contact with the outer peripheral surface of the inner diameter side cylindrical portion 31 of the slinger 30 or faces it via a small gap, the radial movement of the sealing ring 40 relative to the slinger 30 is also restricted, thereby achieving centering of the slinger 30 and the sealing ring 40.

As shown in FIG. 3, separation of the slinger 30 and the seal ring 40 is prevented, and the slinger 30 and the seal ring 40 can be supplied simultaneously when the combined seal ring 20 is transported from the seal factory or when it is supplied to the distribution device of the assembly machine at the bearing factory, improving work efficiency.

Referring to FIG. 1, such a combination seal ring 20 is assembled between the inner peripheral surface of the end of the outer diameter side member 11 and the outer peripheral surface of the end of the inner ring 13, which is the inner diameter side member. The tip edges of the sliding lips 52, 53 of the seal member 51 are brought into sliding contact with the other end side surface of the outer circular ring portion 32 of the slinger 30, and further, the tip edge of one grease lip 54 is brought into sliding contact with the outer peripheral surface of the inner diameter side cylindrical portion 31 to close the inboard end opening of the bearing internal space 10a. This prevents the grease sealed in the bearing internal space 10a from leaking to the outside, and prevents various foreign objects such as rainwater, muddy water, and dust from entering the bearing internal space 10a.

As shown in FIG. 2, the slinger 30 and the seal ring 40 are shown before assembly and in the correct assembly position after assembly, where the locking lip 64 is in a position that interferes with one end side surface 34a of the encoder 34. However, by assembling the combination seal ring 20 to the outer diameter side member 11 and the inner ring 13, the locking lip 64 is deformed to form a non-contact lip, and interference between the locking lip 64 and the encoder 34 is eliminated.

Specifically, as shown in FIG. 4, when the combined seal ring 20 is press-fitted between the outer diameter side member 11 and the inner ring 13 of the inner diameter side member and assembled, the gasket portion 62 is crushed by the small diameter portion 44 and the outer diameter side member 11, and the axial end portion of the overlapping portion 62a of the gasket portion 62 moves toward the axial end side (to the right in FIG. 4) on the outer diameter side, and the non-overlapping portion 62b of the gasket portion 62 is pushed by the outer diameter side member 11 and moves radially inward (downward in FIG. 4).

At the same time, the protruding portion 63, which overhangs from the end face 44a of the small diameter portion 44 toward one axial end, moves radially inward along the non-overlapping portion 62b, causing compressive stress to be applied to the other end side of the protruding portion 63 near the end face 44a of the small diameter portion 44, and pulling the one end side of the locking lip 64 upward, causing the locking lip 64 to deform into an arc shape with the other axial end side convex. As a result, the locking lip 64 moves away from the inclined surface 39, which is the one end side 34a of the encoder 34, and a labyrinth seal is formed between the inclined surface 39 and the small gap.

The inner diameter lip 38 of the encoder 34 contacts the outer peripheral surface of the inner ring 13 with a tightening margin around the entire circumference, sealing the mating surface between the slinger 30 and the inner ring 13.

As described above, in the combined seal ring 20 of this embodiment, the sliding lips 52, 53 of the seal ring 40 are in sliding contact with the other end side surface of the outer ring portion 32 of the slinger 30, and a labyrinth seal is formed between the locking lip 64 of the nose gasket portion 60 and the inclined surface 39 of the encoder 34, so that high sealing performance can be ensured without generating unnecessary torque. Meanwhile, before the combined seal ring 20 is assembled to the outer diameter side member 11 and the inner ring 13, the locking lip 64 of the nose gasket portion 60 and the inclined surface 39 of the encoder 34 overlap when viewed from the axial direction, preventing relative axial movement between the slinger 30 and the seal ring 40, so that the slinger 30 and the seal ring 40 are not separated from each other.
In addition, since the grease lip 54 is in sliding contact with the outer peripheral surface of the inner diameter side cylindrical portion 31 of the slinger 30 with only a slight tightening margin, or is opposed via a gap, a higher level of sealing performance can be ensured and centering of the slinger 30 and the seal ring 40 can be achieved.

Second Embodiment
Next, a combination seal ring applied to a wheel supporting rolling bearing unit of a second embodiment will be described with reference to FIG.
In the second to fifth embodiments described below, only the parts that are different from the first embodiment will be described, and the parts that are the same as those in the first embodiment will be given the same or equivalent symbols, and the description will be simplified or omitted.

In the combined seal ring 20A of the second embodiment, a drain hole 65 is formed in the locking lip 64 of the nose gasket portion 61, which connects the seal space S defined by the slinger 30 and the seal ring 40 to the outside. As a result, even if water or other substances enter the seal space S, they can be immediately drained to the outside through the drain hole 65, and the sealing performance of the combined seal ring 20A can be maintained. The drain hole 65 is preferably located near the base of the locking lip 64 to effectively drain water.

Even if the drainage hole 65 is formed in the locking lip 64, as long as the small diameter side of the locking lip 64 is connected, the other axial end of the locking lip 64 will not be hindered from deforming into a convex arc shape. Rather, the rigidity of the radial middle part of the locking lip 64 is reduced, making it easier to deform into an arc shape.

Third Embodiment
Next, a combination seal ring applied to a wheel supporting rolling bearing unit of a third embodiment will be described with reference to FIG.

In the third embodiment, the combination seal ring 20B has a base 55 of a seal member 51 made of an elastic material such as rubber, which is formed to cover the entire inner circumferential surface 42a of the outer diameter side cylindrical portion 42 of the core metal 41, and is formed integrally with the nose gasket portion 61. This eliminates the need to use expensive stainless steel, which is difficult to press, for the core metal 41, making it possible to reduce costs.

Fourth Embodiment
Next, a combination seal ring applied to a wheel supporting rolling bearing unit of a fourth embodiment will be described with reference to FIG.

Compared to the slinger 30 of the first embodiment, the combination seal ring 20C of the fourth embodiment does not have an encoder 34, and the locking lip 64 of the nose gasket portion 61 overlaps one end side surface 32a of the outer ring portion 32 of the slinger 30 when viewed from the axial direction. In this combination seal ring 20C, the gasket portion 62 is crushed by the small diameter portion 44 and the outer diameter side member 11, so that the locking lip 64 deforms into an arc shape with the other axial end side convex, forming a non-contact lip and forming a labyrinth seal between the slinger 30.

Fifth Embodiment
Next, a combination seal ring applied to a wheel supporting rolling bearing unit of a fifth embodiment will be described with reference to FIG.

Compared to the combination seal ring 20C of the fourth embodiment, the combination seal ring 20D of the fifth embodiment does not have a grease lip 54 of the seal member 51. Therefore, the grease lip 54 does not have the centering effect between the slinger 30 and the seal ring 40. However, the outer diameter side of the outer circular ring portion 32 of the slinger 30 is bent toward the other axial end to form an inclined surface 33, and the locking lip 64 of the nose gasket portion 61 is brought into sliding contact with the inclined surface 33, thereby realizing centering between the slinger 30 and the seal ring 40.

The present invention is not limited to the above-described embodiment, and can be modified, improved, etc. as appropriate.
For example, the wheel supporting rolling bearing unit to which the combined seal ring is assembled is not limited to the embodiment, and may have another configuration.

As described above, the present specification discloses the following:
(1) An outer diameter side member having a double row outer ring raceway on its inner circumferential surface and not rotating even during use;
an inner diameter side member having a double row inner ring raceway on an outer circumferential surface thereof and rotating together with a wheel during use;
a plurality of rolling elements provided between each of the outer ring raceways and each of the inner ring raceways in a rollable manner;
a combination seal ring including a slinger having a substantially L-shaped cross section and a seal ring disposed axially opposite the slinger, the combination seal ring being assembled to the outer diameter side member and the inner diameter side member to seal between the outer diameter side member and the inner diameter side member;
A wheel supporting rolling bearing unit comprising:
The slinger includes an inner diameter side cylindrical portion that is fitted onto the inner diameter side member, and an outer ring portion that extends radially outward from one axial end side of the inner diameter side cylindrical portion,
The seal ring is
a core bar having an outer diameter side cylindrical portion provided on an outer peripheral surface at one axial end side thereof and fitted into the outer diameter side member, and an inner annular portion extending radially inward from the other axial end side of the outer diameter side cylindrical portion;
a seal member fixed to the inner circular ring portion of the core metal and having a plurality of lips that are in sliding contact with the other end side surface of the outer circular ring portion of the slinger;
a gasket portion having an outer diameter larger than the outer diameter of the outer diameter side cylindrical portion and elastically fitting with an inner peripheral surface of the outer diameter side member, a protrusion extending from the outer diameter side cylindrical portion of the core bar toward one axial end side, and a locking lip extending radially inward from one axial end portion of the protrusion and positioned opposite one end side surface of the outer circular ring portion of the slinger or one end side surface of an encoder fixed to the slinger, and the nose gasket portion is fixed to the small diameter portion of the outer diameter side cylindrical portion of the core bar;
Equipped with
the gasket portion has an overlapping portion located on the other end side and overlapping with the small diameter portion of the core in the radial direction, and a non-overlapping portion located on the one end side and not overlapping with the small diameter portion of the core in the radial direction,
When the combined seal ring is press-fitted between the outer diameter side member and the inner diameter side member and assembled, a portion on one axial end side on the outer diameter side of the overlapping portion moves toward the one axial end side, the non-overlapping portion moves radially inward, and the protruding portion also moves radially inward following the non-overlapping portion, so that the locking lip deforms into an arc shape that convex toward the other axial end side, thereby forming a non-contact lip.
Rolling bearing unit for wheel support.
With this configuration, after the combined seal ring is assembled, the locking lip deforms to form a non-contact lip, thereby ensuring high sealing performance while suppressing the increase in rotational torque due to the seal, and the slinger and seal ring will not separate even when the combined seal ring is in a standalone state, making the combined seal ring easier to handle and easier to assemble into a wheel support rolling bearing unit.

(2) The nose gasket portion has a drain hole that communicates an internal space defined by the slinger and the seal ring with the outside.
A rolling bearing unit for supporting a wheel as described in (1).
With this configuration, water that has entered the internal space is reliably discharged, and high sealing performance can be maintained.

(3) A side surface at one end of the outer circular ring portion of the slinger, which is opposed to the locking lip, or a side surface at one end of the encoder fixed to the slinger is an inclined surface.
A wheel supporting rolling bearing unit according to (1) or (2).
According to this configuration, a labyrinth seal is formed between the locking lip that constitutes the non-contact lip and the inclined surface, improving the sealing performance.
Furthermore, when the combined seal ring is in a single state and the locking lip is in contact with the inclined surface, the slinger and the seal ring can be centered.

10 Wheel supporting rolling bearing unit 11 Outer diameter side member 11a Outer ring raceway 12 Hub ring (inner diameter side member)
13 Inner ring (inner diameter side member)
12a, 13a Inner ring raceway 14 Ball (rolling element)
20, 20A, 20B, 20C, 20D Combined seal ring 30 Slinger 31 Inner diameter side cylindrical portion 32 Outer circular ring portion 32a One end side surface 33, 39 of outer circular ring portion of slinger Inclined surface 34 Encoder 34a One end side surface 40 Seal ring 41 Core metal 42 Outer diameter side cylindrical portion 43 Inner circular ring portion 44 Small diameter portion 51 Seal member 52, 53 Sliding lip (lip)
54 Grease lip 61 Nose gasket portion 62 Gasket portion 62a Overlapped portion 62b Non-overlapped portion 63 Projection portion 64 Engagement lip 65 Water drain hole S Sealed space

Claims (3)

an outer diameter side member having a double row outer ring raceway on its inner circumferential surface and not rotating even during use;
an inner diameter side member having a double row inner ring raceway on an outer circumferential surface thereof and rotating together with a wheel during use;
a plurality of rolling elements provided between each of the outer ring raceways and each of the inner ring raceways in a rollable manner;
a combination seal ring including a slinger having a substantially L-shaped cross section and a seal ring disposed axially opposite the slinger, the combination seal ring being assembled to the outer diameter side member and the inner diameter side member to seal between the outer diameter side member and the inner diameter side member;
A wheel supporting rolling bearing unit comprising:
The slinger includes an inner diameter side cylindrical portion that is fitted onto the inner diameter side member, and an outer ring portion that extends radially outward from one axial end side of the inner diameter side cylindrical portion,
The seal ring is
a core bar having an outer diameter side cylindrical portion provided on an outer peripheral surface at one axial end side thereof and fitted into the outer diameter side member, and an inner annular portion extending radially inward from the other axial end side of the outer diameter side cylindrical portion;
a seal member fixed to the inner circular ring portion of the core metal and having a plurality of lips that are in sliding contact with the other end side surface of the outer circular ring portion of the slinger;
a gasket portion having an outer diameter larger than the outer diameter of the outer diameter side cylindrical portion and elastically fitting with an inner peripheral surface of the outer diameter side member, a protrusion extending from the outer diameter side cylindrical portion of the core metal toward one axial end side, and a locking lip extending radially inward from one axial end portion of the protrusion and positioned opposite one end side surface of the outer circular ring portion of the slinger or one end side surface of an encoder fixed to the slinger, and the nose gasket portion is fixed to the small diameter portion of the outer diameter side cylindrical portion of the core metal;
Equipped with
the gasket portion has an overlapping portion located on the other end side and overlapping with the small diameter portion of the core in the radial direction, and a non-overlapping portion located on the one end side and not overlapping with the small diameter portion of the core in the radial direction,
When the combined seal ring is press-fitted between the outer diameter side member and the inner diameter side member and assembled, a portion on one axial end side on the outer diameter side of the overlapping portion moves toward the one axial end side, the non-overlapping portion moves radially inward, and the protruding portion also moves radially inward following the non-overlapping portion, so that the locking lip deforms into an arc shape that convex toward the other axial end side, thereby forming a non-contact lip.
Rolling bearing unit for wheel support. The nose gasket portion has a drain hole communicating an internal space defined by the slinger and the seal ring with the outside.
2. A wheel supporting rolling bearing unit according to claim 1. The side surface of one end of the outer circular ring portion of the slinger, which faces the locking lip, or the side surface of one end of the encoder fixed to the slinger is an inclined surface.
3. A wheel supporting rolling bearing unit according to claim 1 or 2.

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