JP2020115026A - Combined seal ring and hub unit bearing - Google Patents

Abstract

To realize a structure capable of sufficiently securing sealability for a long period.SOLUTION: A rotary opposite surface 40 provided on a slinger 26 and a stationary opposite surface 39 provided on a labyrinth slip 36 are made closely face each other, thereby forming a labyrinth seal 41 between the rotary opposite surface 40 and the stationary opposite surface 39. The labyrinth slip 36 elastically deforms in a direction in which the distance between the stationary opposite surface 39 and the rotary opposite surface 40 decreases with the rotation of a hub.SELECTED DRAWING: Figure 2

Description

TECHNICAL FIELD The present invention relates to a combined seal ring formed by combining a slinger and a seal ring, and a hub unit bearing including the combined seal ring.

Hub unit bearings for rotatably supporting a vehicle wheel with respect to a suspension system are used in an environment where muddy water is directly splashed. Therefore, a sealing device is incorporated in such a hub unit bearing to prevent foreign matter such as rainwater and mud from entering the rolling element installation space in which the rolling element is installed, and the enclosed grease leaks to the outside. To prevent that. Specifically, the opening at the axial end of the rolling element installation space is closed by a combined seal ring including a slinger and a seal ring.

FIG. 9 shows a combination seal ring described in Japanese Unexamined Patent Publication No. 2018-59594. The combination seal ring 100 includes a slinger 101 and a seal ring 102.

The slinger 101 has a fitting cylinder portion 104 fitted onto the axial end portion of the inner ring 103, and a circle bent outward in the radial direction from an end portion of the fitting cylinder portion 104 on one axial side (right side in FIG. 9). And a wheel plate portion 105.

The seal ring 102 includes a metal cored bar 106 and an elastic sealant 107.

The core metal 106 includes a cylindrical portion 109 fitted in an axial end portion of the outer ring 108, and a bent portion 110 bent inward in the radial direction from an end portion of the cylindrical portion 109 on the other axial side (left side in FIG. 9). With.

The seal material 107 includes a base portion 111, a plurality (three in the illustrated example) of seal lips 112a, 112b, 112c, and a labyrinth slip 113. The base portion 111 is fixed to the core metal 106 so as to cover the inner peripheral surface of the cylindrical portion 109 of the core metal 106 and the end portion on one side in the axial direction and the axial one side surface and the end portion on the radial inner side of the bent portion 110. Has been done. Each of the seal lips 112a, 112b, 112c extends from the base portion 111 toward the outer peripheral surface of the fitting cylinder portion 104 of the slinger 101 or the other side surface in the axial direction of the annular plate portion 105, and the tip end thereof is fitted to the fitting cylinder portion. It is in sliding contact with the outer peripheral surface of 104 or the other axial side surface of the circular plate portion 105. The labyrinth slip 113 is an extended base portion that is present on the outer side in the radial direction than the joining portion 117 to which the base end portion of the outermost seal lip 112a of the seal lips 112a, 112b, 112c of the base portion 111 is joined. It extends from 118 toward one side in the axial direction and inward in the radial direction. By making the leading end surface of the labyrinth slip 113 closely face the other axial side surface of the circular plate portion 105 of the slinger 101, the leading end surface of the labyrinth slip 113 and the other axial side surface of the circular ring plate portion 105 can be formed. A labyrinth seal 114 is formed between the two.

According to the hub unit bearing including such a combined seal ring 100, it is possible to prevent foreign matter such as rainwater and mud from entering through the opening of the axial end portion of the rolling element installation space, and to enter the rolling element installation space. It is possible to prevent the enclosed grease from leaking to the outside.

JP, 2008-59594, A

In the structure described in JP-A-2018-59594, the labyrinth slip 113 extends from the base 111 toward one side in the axial direction and toward the inside in the radial direction. Therefore, in the portion of the seal ring 102, which is located on the other side in the axial direction of the labyrinth slip 113, a groove 115 that is recessed radially outward is formed over the entire circumference. Therefore, foreign matter such as rainwater or mud is introduced from the portion between the tip end surface of the labyrinth slip 113 and the other axial side surface of the annular plate portion 105 of the slinger 101 to the inside of the labyrinth seal 114 (the rolling element installation space side). When the foreign matter 116 once enters, the foreign matter 116 may be deposited on the lower portion of the concave groove 115 when the hub unit bearing including the combined seal ring 100 is assembled to the vehicle. The foreign matter 116 deposited in the groove 115 is difficult to be discharged to the external space, and may wear the tip portions of the seal lips 112a, 112b, 112c, and reduce durability.

In view of the above-mentioned circumstances, the present invention has been devised to realize a structure of a combined seal ring and a hub unit bearing including the combined seal ring, which can sufficiently secure the sealing property for a long period of time. is there.

The combination seal ring of the present invention comprises a slinger and a seal ring.
The slinger has a fitting cylinder portion and an annular plate portion bent outward in the radial direction from the axial end portion of the fitting cylinder portion.
The seal ring has a cored bar and a sealing material fixed to the cored bar.
The sealing material has a base, one or more sealing lips, and a labyrinth slip.
The base is fixed to the core metal.
The seal lip extends from the base portion toward the surface of the slinger, and a tip portion is in sliding contact with the surface of the slinger over the entire circumference.
The labyrinth slip is, in the axial direction, from an extending base portion that is present on a radially outer side of a joint portion to which a base end portion of a seal lip on the outermost radial direction of the seal lip is joined, of the base portion. It includes a portion extending toward the circular plate portion and radially outward.
Furthermore, in the combination seal ring of the present invention, by making the rotation facing surface provided on the slinger or another member fixed to the slinger and the fixed facing surface provided on the labyrinth slip closely face each other, A labyrinth seal is formed between the rotary facing surface and the fixed facing surface.
Further, the labyrinth slip is elastically deformed with the relative rotation of the slinger and the seal ring such that the distance between the fixed facing surface and the rotating facing surface becomes smaller.

The labyrinth slip has an outer circumferential surface or an inner circumferential surface having the fixed facing surface, and the slinger or another member fixed to the slinger is a circumferential surface radially facing the fixed facing surface. In addition, it may have the rotation facing surface.

Alternatively, the labyrinth slip is bent from the extending base portion toward the annular plate portion in the axial direction and extends radially outward, and the labyrinth slip is bent from the distal end portion of the base half portion to form a diameter. The front half of the circular ring extending outward in the direction, and the fixed facing surface provided on the side of the front half nearer to the circular plate in the axial direction. You can In this case, the slinger or another member fixed to the slinger has the rotation facing surface on a side surface orthogonal to the central axis of the slinger and axially facing the fixed facing surface. ..
Additionally, the slinger or another member fixed to the slinger may have a step surface facing inward in the radial direction over the entire circumference. In this case, the opposing area between the tip surface of the first half portion of the labyrinth slip and the step surface may be set such that the seal ring and the slinger are relatively opposed to each other as compared with a state in which the seal ring and the slinger are not relatively rotated. Increase while rotating.

The hub unit bearing of the present invention includes an outer ring member, an inner ring member, a plurality of rolling elements, and a combination seal ring.
The outer ring member has an outer ring raceway on its inner peripheral surface.
The inner ring member has an inner ring raceway on the outer peripheral surface.
The rolling element is arranged between the outer ring raceway and the inner ring raceway.
The combination seal ring closes an opening at an axial end of a rolling element installation space existing between an inner peripheral surface of the outer ring member and an outer peripheral surface of the inner ring member.
Particularly, in the hub unit bearing of the present invention, the combination seal ring is the combination seal ring of the present invention, and the fitting cylinder portion of the slinger is externally fitted and fixed to an axial end portion of the inner ring member, and the seal is formed. The core metal of the ring is internally fitted and fixed to the axial end portion of the outer ring member.

According to the combination seal ring and the hub unit bearing of the present invention, it is possible to sufficiently secure the hermeticity for a long period of time.

FIG. 1 is a cross-sectional view of a hub unit bearing according to a first example of the embodiment. FIG. 2 is an enlarged view of part X in FIG. FIG. 3 is a diagram corresponding to FIG. 2, showing a second example of the embodiment. FIG. 4 is a diagram corresponding to FIG. 2, showing a third example of the embodiment. FIG. 5 is an enlarged view of the Y portion of FIG. FIG. 6 is a diagram corresponding to FIG. 2, showing a fourth example of the embodiment. FIG. 7 is a diagram corresponding to FIG. 2, showing a fifth example of the embodiment. FIG. 8 is a diagram corresponding to FIG. 2, showing a sixth example of the embodiment. FIG. 9 is an enlarged view showing a cross section of a portion located above and a cross section of a portion located below in a mounted state in an example of a conventional structure of a combined seal ring.

[First Example of Embodiment]
1 and 2 show a first example of an embodiment of the present invention. The hub unit bearing 1 of this example includes an outer ring 2 that is an outer ring member that does not rotate in a used state, a hub 3 that is an inner ring member that rotates together with a wheel and a braking rotating body such as a disk or a drum in a used state, The individual rolling elements 4, the outer sealing member 5, and the combination seal ring 6 are provided.

The outer ring 2 is made of a hard metal such as medium carbon steel and is provided with double-row outer ring raceways 7a and 7b and a stationary flange 8 for fixing the outer ring 2 to a suspension device. The double-row outer ring raceways 7a, 7b are respectively formed in the axially intermediate portions of the inner peripheral surface of the outer ring 2. The stationary flange 8 is formed at an axially intermediate portion of the outer ring 2 so as to project outward in the radial direction, and has support holes 9 at a plurality of positions in the circumferential direction. The outer ring 2 is supported and fixed to the knuckle of the suspension device by a coupling member such as a bolt screwed or inserted into the support hole 9.

The hub 3 is arranged coaxially with the outer ring 2 on the radially inner side of the outer ring 2, and includes double-row inner ring raceways 10a and 10b and a rotary flange 11 for supporting and fixing the wheels and the braking rotor. .. The double-row inner ring raceways 10a, 10b are formed on a portion of the outer peripheral surface of the hub 3 that faces the double-row outer ring raceways 7a, 7b. The rotary flange 11 is formed at a portion of the hub 3 that is located axially outside of the axially outer end of the outer ring 2 so as to project radially outward, and at a plurality of circumferential positions. Has a mounting hole 12. The wheel and the braking rotor are supported on the rotary flange 11 by studs 13 press-fitted into the mounting holes 12 or hub bolts screwed into the mounting holes 12 that are screw holes.

In this example, the outer side in the axial direction refers to the left side in FIGS. 1 and 2 which is the outer side in the vehicle width direction when the hub unit bearing 1 is assembled to the vehicle, and the inner side in the axial direction is the state assembled to the vehicle. Is the right side of FIGS. 1 and 2 which is the center side in the width direction of the vehicle.

In this example, the hub 3 is formed by coupling and fixing the hub body 14 and the inner ring 15.

The hub body 14 has the inner ring raceway 10a on the outer side in the axial direction among the double-row inner ring raceways 10a, 10b on the outer peripheral surface in the axial direction, and is present on the outer side in the axial direction than the inner ring raceway 10a on the outer side in the axial direction. The portion has a rotary flange 11 protruding outward in the radial direction. Further, the hub body 14 has a small-diameter cylindrical portion 16 having an outer diameter dimension smaller than that of a portion adjacent to the axially outer side in an axially inner portion, and an axially outer end portion of the small-diameter cylindrical portion 16 has an axially outer portion. It has a step portion 17 facing inward.

The inner ring 15 has an inner ring raceway 10b on the inner side in the axial direction among the double-row inner ring raceways 10a and 10b on the outer peripheral surface of the intermediate portion in the axial direction.

In this example, in a state where the inner ring 15 is fitted onto the small-diameter tubular portion 16, the portion of the small-diameter tubular portion 16 that projects axially inward from the axially inner end surface of the inner ring 15 is plastically oriented radially outward. The caulked portion 18 formed by being deformed suppresses the axially inner end surface of the inner ring 15. As a result, the inner ring 15 is axially sandwiched between the caulked portion 18 and the step portion 17, and the hub body 14 and the inner ring 15 are coupled and fixed to each other, thereby forming the hub 3.

The hub 3 is formed on the outer peripheral surface of the portion of the hub body that projects axially inward from the axially inner end surface of the inner ring in a state where the inner ring is fitted onto the small-diameter cylindrical portion of the hub body. Alternatively, a nut may be screwed onto the male screw portion to be coupled and fixed.

A plurality of rolling elements 4 are rolled between the double-row outer ring raceways 7a, 7b and the double-row inner ring raceways 10a, 10b while being held in the pockets 20 of the cage 19, respectively. Arranged freely. In this example, balls are used as the rolling elements 4, but tapered rollers can also be used.

The outer sealing member 5 is a seal ring and is made of a metal plate such as a steel plate having sufficient strength and rigidity. The outer sealing member 5 has an outer cored bar 21 internally fitted and fixed to an axially outer end of the outer ring 2 and a rubber. The outer seal member 23 is made of an elastic material such as an elastomer and is fixed to the outer core metal 21 and has a plurality (three in the illustrated example) of seal lips 22a, 22b, 22c.

In this example, the tip of the innermost radial seal lip 22c of the seal lips 22a, 22b, 22c is in sliding contact with the outer peripheral surface of the shoulder 24a adjacent to the axial outer side of the outer ring raceway 7a. At the same time, the tip portions of the remaining seal lips 22a and 22b are slidably brought into contact with the axial inner surface of the rotary flange 11 or the connecting portion between the axial inner surface of the rotary flange 11 and the outer peripheral surface of the shoulder 24a. ing. As a result, the grease existing between the inner peripheral surface of the outer ring 2 and the outer peripheral surface of the hub 3 and sealed in the cylindrical rolling element installation space 25 in which the rolling elements 4 are arranged has the grease in the rolling element installation space 25. This prevents foreign matter such as mud and rainwater from entering through the axially outer opening of the rolling element installation space 25 while preventing leakage from the axially outer opening.

The combination seal ring 6 includes a slinger 26 and a seal ring 27.

The slinger 26 has a rustproof property such as a stainless steel plate, and is formed by bending a metal plate having sufficient strength and rigidity into an annular shape with an L-shaped cross section. It has a tubular portion 28 and an annular plate portion 29 bent at a right angle from the axially inner end portion of the fitting tubular portion 28 to the radial outer side. The fitting tubular portion 28 is provided on the outer peripheral surface of the end portion of the hub 3 on the inner side in the axial direction, specifically, on the outer peripheral surface of the shoulder portion 24b of the inner ring 15 that is adjacent to the inner side of the inner ring raceway 10b on the inner side in the axial direction. , It is externally fitted and fixed by interference fit.

The seal ring 27 includes a cored bar 30 and a seal material 31 fixed to the cored bar 30.

The cored bar 30 is formed by bending a metal plate having sufficient strength and rigidity such as a steel plate to have an annular shape as a whole with a substantially L-shaped cross section, and the cylindrical portion 32 and the cylindrical portion 32. It has a bent portion 33 that is bent inward in the radial direction from the end portion on the outer side in the axial direction. The cylindrical portion 32 is internally fitted and fixed to the inner peripheral surface of the end portion of the outer ring 2 on the inner side in the axial direction by interference fitting.

The sealing material 31 is made of an elastic material such as an elastomer such as rubber, and is fixed to the surface of the cored bar 30 by vulcanization adhesion over the entire circumference. The sealing material 31 includes a base portion 34, a plurality (three in the illustrated example) of sealing lips 35 a, 35 b, and 35 c, and one labyrinth slip 36.

The base portion 34 is vulcanized and bonded to the outer peripheral surface and the axially inner end portion of the cylindrical portion 32 of the core metal 30 and the axially inner side surface and the radially inner end portion of the bent portion 33 so as to cover the portion. It is fixed by.

The seal lips 35a, 35b, 35c extend from the base portion 34 toward the surface of the slinger 26, and the tip portions are in sliding contact with the surface of the slinger 26 over the entire circumference. Specifically, of the seal lips 35a, 35b, 35c, the outermost radial seal lip 35a extends axially inward and radially outward from the base 34 toward the circular plate portion 29 of the slinger 26. The tip end portion is slidably contacted with the outer surface in the axial direction of the circular plate portion 29 over the entire circumference. The two radially inner seal lips 35b, 35c extend radially inward from the base portion 34 toward the fitting cylinder portion 28 of the slinger 26, and the distal end portions thereof are provided on the outer peripheral surface of the fitting cylinder portion 28. Is slid over the entire circumference.

The labyrinth slip 36 has a base half portion 37 and a front half portion 38.

The base half portion 37 is axially inward and radially inward from an extension base 50 existing radially outward of a joint portion 49 of the base portion 34 to which the proximal end portion of the outermost radial seal lip 35a is joined. It extends toward the outside. Therefore, the inner peripheral surface of the base half portion 37 is a conical surface inclined in a direction in which the inner diameter increases toward the inner side in the axial direction. In this example, in the surface of the base portion 34, a portion adjacent to the axially outer side of the inner peripheral surface of the base half portion 37 is made to exist on the same conical surface as the inner peripheral surface of the base half portion 37. The connecting portion 49 and the connecting portion 49 to which the base end portion of the outermost seal lip 35a is connected are connected by a flat surface orthogonal to the central axis of the outer ring 2. In short, in the combined seal ring 6 of the present example, the combined seal ring 100 described in JP2018-59594A is provided in the space 48 existing between the labyrinth slip 36 and the outermost radial seal lip 35a. However, there is no recessed groove 115 that is recessed radially outward (see FIG. 9 ).

The first half portion 38 has a circular ring shape and is bent from the tip end portion (end portion on the inner side in the axial direction) of the base half portion 37 and extends outward in the radial direction. The first half portion 38 has a fixed facing surface 39 on the inner surface in the axial direction which is a flat surface orthogonal to the central axis of the outer ring 2. In this example, the fixed facing surface 39 is axially closely opposed to the rotating facing surface 40 provided on the radially outer portion of the axially outer surface of the annular plate portion 29 of the slinger 26, whereby the fixed facing surface 39 is provided. A labyrinth seal 41 extending in the radial direction is formed between the and the rotation facing surface 40.

Further, in this example, the thickness of the labyrinth slip 36 is appropriately regulated, so that the rigidity of the labyrinth slip 36 is set to an appropriate magnitude. That is, as the hub 3 rotates, the labyrinth slip 36 reduces the gap between the fixed facing surface 39 and the rotating facing surface 40 due to the action of the airflow generated between the fixed facing surface 39 and the rotating facing surface 40. The rigidity of the labyrinth slip 36 is regulated so that it can be elastically deformed in the direction.

By closing the axially inner opening of the rolling element installation space 25 with such a combination seal ring 6, the grease enclosed in the rolling element installation space 25 leaks from the axially inner opening of the rolling element installation space 25. In addition, the foreign matter such as mud and rainwater is prevented from entering through the axially inner opening of the rolling element installation space 25.

According to the hub unit bearing 1 of this example, the sealing performance of the axially inner opening of the rolling element installation space 25 in which the combination seal ring 6 is installed can be sufficiently ensured for a long period of time.

That is, in this example, by extending the base half portion 37 of the labyrinth slip 36 that forms the seal ring 27 from the base portion 34 toward the inner side in the axial direction and the outer side in the radial direction, the inner peripheral surface of the base half portion 37 is formed. The conical surface is inclined so that the inner diameter increases toward the inner side in the axial direction. For this reason, in this example, the space 48 existing between the labyrinth slip 36 and the outermost seal lip 35a in the radial direction, such as the combination seal ring 100 disclosed in JP-A-2018-59594, has a radial direction. There is no recessed groove 115 recessed to the outside. Therefore, tentatively, foreign matter such as rainwater or muddy water is generated between the inner surface of the first half portion 38 in the axial direction (fixed facing surface 39) and the outer surface of the annular plate portion 29 of the slinger 26 in the axial direction (rotating facing surface 40). Even when the space 48 inside the labyrinth seal 41 (on the rolling element installation space 25 side) enters the space 48 through the interspace (labyrinth seal 41), the foreign matter can be prevented from accumulating in the space 48. Therefore, the foreign matter that has entered the space 48 is guided by the action of gravity along the inner peripheral surface of the base half portion 37 and moves inward in the axial direction, and then the centrifugal force accompanying the rotation of the hub 3 (slinger 26). Is discharged to the external space through the labyrinth seal 41.

Further, in this example, since the rigidity of the labyrinth slip 36 is set to an appropriate magnitude, when the hub 3 rotates as the vehicle travels, due to the action of the air flow generated between the fixed facing surface 39 and the rotating facing surface 40. , The labyrinth slip 36 elastically deforms in the direction in which the distance between the fixed facing surface 39 and the rotating facing surface 40 decreases. As a result, the width dimension of the labyrinth seal 41 in the axial direction can be reduced, and the sealing effect of the labyrinth slip 36 can be improved. On the other hand, when the hub 3 stops with the stop of the vehicle, the first half portion 38 elastically restores, and the distance between the fixed facing surface 39 and the rotating facing surface 40 increases. Therefore, foreign matter that has entered the space 48 existing between the labyrinth slip 36 and the outermost seal lip 35a in the radial direction can be easily discharged to the external space through the labyrinth seal 41 by the action of gravity.

For the above reasons, even if a foreign matter enters the space 48 inside the labyrinth seal 41, the foreign matter accumulates in the space existing between the labyrinth slip 36 and the radially outermost seal lip 35a. Can be prevented. Therefore, it is possible to prevent the tips of the seal lips 35a, 35b, and 35c from being worn by foreign matter, and it is possible to secure the sealing performance of the axially inner opening of the rolling element installation space 25 for a long period of time.

[Second Example of Embodiment]
FIG. 3 shows a second example of the embodiment of the present invention. The slinger 26a that constitutes the combined seal ring 6a of this example has a substantially U-shaped (generally U-shaped) cross-sectional shape. That is, the slinger 26 a includes a fitting cylinder portion 28 fitted on the outer peripheral surface of the end portion of the hub 3 (see FIG. 1) on the inner side in the axial direction, and a radial direction from the end portion of the fitting cylinder portion 28 on the inner side in the axial direction. The circular ring plate portion 29 is bent outward at a right angle, and the eaves portion 42 is bent at a right angle axially outward from the radially outer end of the circular plate portion 29. The eaves portion 42 has a rotation facing surface 40a on an inner peripheral surface that is a cylindrical surface centered on the central axis of the hub 3.

Further, the labyrinth slip 36a of the seal material 31a that constitutes the seal ring 27a is bent from the base half portion 37a extending axially inward and radially outward from the base portion 34 and the tip portion of the base half portion 37a. , A cylindrical first half portion 38a extending inward in the axial direction. The inner peripheral surface of the base half portion 37a is a conical surface inclined in a direction in which the inner diameter increases toward the inner side in the axial direction. The first half portion 38a has a fixed facing surface 39a on the outer peripheral surface which is a cylindrical surface centered on the central axis of the outer ring 2 (see FIG. 1). In this example, the fixed facing surface 39a of the labyrinth slip 36a and the rotary facing surface 40a of the slinger 26a are made to closely face each other in the radial direction, so that the fixed facing surface 39a and the rotary facing surface 40a extend in the axial direction. Constitutes a labyrinth seal 41a.

Further, in this example, the thickness of the labyrinth slip 36a is appropriately regulated, so that the rigidity of the labyrinth slip 36a is set to an appropriate magnitude. Specifically, as the hub 3 rotates, the labyrinth slip 36a moves between the fixed facing surface 39a and the rotating facing surface 40a by the action of the air flow generated between the fixed facing surface 39a and the rotating facing surface 40a. The rigidity of the labyrinth slip 36a is regulated to such an extent that the labyrinth slip 36a can be elastically deformed in the direction in which the distance becomes smaller.

Also in the case of this example, since the base half portion 37a of the labyrinth slip 36a is extended inward in the axial direction and outward in the radial direction from the base portion 34, between the labyrinth slip 36a and the seal lip 35a at the outermost radial direction. In the existing space 48a, there is no recessed groove 115 that is recessed outward in the radial direction, such as the combination seal ring 100 described in JP-A-2018-59594. Therefore, even if foreign matter such as rainwater or muddy water enters the space 48a inside (the rolling element installation space 25 side) of the labyrinth seal 41a, the foreign matter can be prevented from accumulating in the space 48a. it can.

Further, since the rigidity of the labyrinth slip 36a is set to an appropriate level, when the hub 3 rotates as the vehicle travels, the labyrinth slip 36a rotates due to the action of the airflow generated between the fixed facing surface 39a and the rotating facing surface 40a. 36a elastically deforms in the direction in which the distance between the fixed facing surface 39a and the rotating facing surface 40a becomes smaller. As a result, the width dimension of the labyrinth seal 41a in the radial direction can be reduced, and the sealing effect of the labyrinth slip 36a can be improved. On the other hand, when the hub 3 stops with the stop of the vehicle, the first half portion 38a elastically restores, the gap between the fixed facing surface 39a and the rotating facing surface 40a expands, and the labyrinth slip 36a and the outermost radial direction. The foreign matter having entered the space 48a existing between the seal lip 35a and the seal lip 35a can be easily discharged to the external space. The configuration and operational effects of the other parts are similar to those of the first example of the embodiment.

[Third Example of Embodiment]
4 and 5 show a third example of the embodiment of the present invention. The combination seal ring 6b of this example includes an encoder 43 in addition to the slinger 26 and the seal ring 27. The encoder 43 is made of a permanent magnet such as a rubber magnet or a plastic magnet, and is formed in a circular ring shape as a whole. The encoder 43 is coaxial with the hub 3 (see FIG. 1) on the axial inner surface of the circular plate portion 29 of the slinger 26. It is attached to and fixed to. The encoder 43 has, at its radially outer end, a ridge 44 projecting outward in the axial direction from the axially outer surface (rotational facing surface 40) of the circular plate portion 29 over the entire circumference, The inner peripheral surface of 44 has a step surface 45 that faces the inner side in the radial direction. In this example, the step surface 45 is a conical surface inclined in a direction in which the inner diameter increases toward the outer side in the axial direction.

In this example, the fixed facing surface 39 provided on the front half portion 38 of the labyrinth slip 36 is axially closely opposed to the rotary facing surface 40 provided on the annular plate portion 29 of the slinger 26, and the front half portion is also provided. The tip end surface (outer peripheral surface) of 38 is closely opposed to the step surface 45 in the radial direction. As a result, a labyrinth seal 41 extending in the radial direction is formed between the fixed facing surface 39 and the rotating facing surface 40, and the labyrinth seal 41 is provided between the tip surface of the first half portion 38 and the step surface 45. An axial labyrinth seal 46 is formed by bending from the radially outer end portion to the axial outer side. In this example, in the state where the hub 3 is not rotating, the axially inner portion of the tip end surface of the first half portion 38 closely faces the axially outer portion of the step surface 45. In other words, when the hub 3 is not rotating, the axially outer side surface of the first half portion 38 is located axially outwardly of the axially outer side surface of the protruding portion 44.

In this example, when the labyrinth slip 36 elastically deforms in the direction in which the distance between the fixed facing surface 39 and the rotating facing surface 40 decreases as the hub 3 rotates, the width dimension of the labyrinth seal 41 in the axial direction decreases. At the same time, the facing area between the tip surface of the first half portion 38 and the step surface 45 increases. In other words, the axial length of the portion where the tip surface of the first half portion 38 and the step surface 45 overlap in the radial direction, that is, the axial length of the labyrinth seal 46 in the axial direction becomes long.

In this example, when the labyrinth slip 36 elastically deforms as the hub 3 rotates, the width dimension of the labyrinth seal 41 in the axial direction decreases, and the labyrinth seal 41 bends axially outward from the radially outer end. The axial length of the labyrinth seal 46 in the axial direction is increased. Therefore, the sealing effect of the labyrinth slip 36 can be further improved as compared with the combined seal ring 6 of the first example of the embodiment.

On the other hand, when the labyrinth slip 36 elastically restores as the hub 3 stops, the axial width of the labyrinth seal 41 increases and the axial length of the labyrinth seal 46 decreases in the axial direction. Therefore, the foreign matter having entered the space 48 existing between the labyrinth slip 36 and the outermost radial seal lip 35a is discharged to the external space through the labyrinth seal 41 and the axial labyrinth seal 46 by the action of gravity. Can be made easier. In particular, in this example, since the step surface 45 is a conical surface inclined in a direction in which the inner diameter increases toward the outer side in the axial direction, the foreign matter that has moved to the tip of the first half portion 38 is guided toward the external space. can do. The configuration and operational effects of the other parts are similar to those of the first example of the embodiment.

[Fourth Example of Embodiment]
FIG. 6 shows a fourth example of the embodiment of the present invention. The combination seal ring 6c of this example includes, in addition to the slinger 26 and the seal ring 27, an encoder 43a that is attached and fixed to the axially inner side surface and the radially outer end portion of the annular plate portion 29 of the slinger 26. The encoder 43a has, at its radially outer end portion, a convex portion 47 that projects axially outward from the axial outer surface of the slinger 26, and has a tip surface (axial outer surface) of the convex portion 47. The radially inner portion has a rotation facing surface 40b which is a flat surface orthogonal to the central axis of the hub 3 (see FIG. 1). Further, the encoder 43a has, on the radially outer side portion of the tip end surface of the convex portion 47, a ridge 44a projecting axially outwardly from the radially inner portion (rotational facing surface 40b), and The inner peripheral surface has a step surface 45a facing inward in the radial direction. The step surface 45a is a conical surface inclined in a direction in which the inner diameter increases toward the outer side in the axial direction.

In this example, the fixed facing surface 39 provided on the first half portion 38 of the labyrinth slip 36 is axially opposed to the rotation facing surface 40b provided on the encoder 43a, and the tip end surface (outer periphery) of the first half portion 38 is provided. Surface) is closely opposed to the step surface 45a in the radial direction. As a result, a labyrinth seal 41b extending in the radial direction is formed between the fixed facing surface 39 and the rotating facing surface 40b, and the labyrinth seal 41b is provided between the tip surface of the first half portion 38 and the step surface 45a. An axial labyrinth seal 46a is formed by bending from the radially outer end to the axial outer side. In this example, in the state where the hub 3 is not rotating, the axially inner portion of the tip end surface of the first half portion 38 closely faces the axially outer portion of the step surface 45a. The configuration and the effect of other parts are the same as those of the first and third examples of the embodiment.

[Fifth Example of Embodiment]
FIG. 7 shows a fifth example of the embodiment of the present invention. The slinger 26b constituting the combined seal ring 6d of the present example is directed toward the axially outer side and the radially inner side from the radially outer end of the circular ring plate portion 29 in addition to the fitting tubular portion 28 and the circular ring plate portion 29. And has an eaves portion 42a bent at an acute angle. Therefore, the outer peripheral surface of the eaves portion 42a is a conical surface inclined in a direction in which the outer diameter increases toward the inner side in the axial direction.

In addition, in this example, the entire labyrinth slip 36b of the seal material 31b forming the seal ring 27b extends from the base portion 34 toward the inner side in the axial direction and the outer side in the radial direction. The inner peripheral surface of the labyrinth slip 36b is a conical surface inclined in a direction in which the inner diameter increases toward the inner side in the axial direction. In the present example, the fixed facing surface 39b provided on the axially inner side portion of the inner peripheral surface of the labyrinth slip 36b and the rotary facing surface 40c provided on the axially outer side portion of the outer peripheral surface of the eaves portion 42a are closely opposed to each other. As a result, a labyrinth seal 41c is formed between the fixed facing surface 39b and the rotating facing surface 40c so as to extend radially outward as it goes axially inward.

In this example, when the hub 3 rotates, the labyrinth slip 36b reduces the gap between the fixed facing surface 39b and the rotating facing surface 40c due to the action of the airflow generated between the fixed facing surface 39b and the rotating facing surface 40c. Elastically deforms in the direction. As a result, the width dimension of the labyrinth seal 41c is reduced, and the sealing effect of the labyrinth slip 36b can be improved. On the other hand, when the hub 3 stops, the labyrinth slip 36b elastically restores and the width dimension of the labyrinth seal 41c increases, so that it exists between the labyrinth slip 36b and the outermost radial seal lip 35a. The foreign matter that has entered the space 48b can be easily discharged. In particular, in this example, since the foreign matter can be guided radially outward by the inner peripheral surface of the labyrinth slip 36b, which is the conical surface, the foreign matter dischargeability can be further improved. The configurations and operational effects of the other parts are similar to those of the first and second examples of the embodiment.

[Sixth Example of Embodiment]
FIG. 8 shows a sixth example of the embodiment of the present invention. The slinger 26c constituting the combined seal ring 6e of the present example has an eaves portion 42b bent at a right angle from the radially outer end of the circular plate portion 29 to the axially outer side. Further, the encoder 43b has, at its radially outer end portion, a convex portion 47a having a substantially trapezoidal cross section and formed so as to cover the eaves portion 42b over the entire circumference. The convex portion 47a has an outer peripheral surface that is a conical surface that is inclined in a direction in which the outer diameter increases toward the outer side in the axial direction, while the inner peripheral surface is centered on the central axis of the hub 3 (see FIG. 1). And a cylindrical surface.

In this example, the fixed facing surface 39b provided on the axially inner side portion of the inner peripheral surface of the labyrinth slip 36b and the rotary facing surface 40d provided on the axially outer side portion of the outer peripheral surface of the convex portion 47a are closely opposed to each other. As a result, a labyrinth seal 41d is formed between the fixed facing surface 39b and the rotating facing surface 40d so as to extend radially outward as it goes axially inward.

In this example, by making the inner peripheral surface of the convex portion 47a a cylindrical surface, a concave portion that is recessed radially outward is provided in the space 48b that exists between the labyrinth slip 36b and the seal lip 35a that is the radially outermost portion. It is prevented from being formed. This prevents foreign matter that has entered the space 48b from accumulating in the space 48b. The configuration and operational effects of the other parts are the same as those of the first and fifth examples of the embodiment.

In each of the above-described embodiments, the case where the combined seal ring is installed in the opening on the inner side in the axial direction of the rolling element installation space has been described, but when the hub unit bearing of the present invention is implemented, It is also possible to install the combination seal ring of (1) in the opening on the axially outer side of the rolling element installation space.

1 Hub unit bearing 2 Outer ring 3 Hub 4 Rolling element 5 Outer sealing member 6, 6a, 6b, 6c, 6d, 6e Combination seal ring 7a, 7b Outer ring raceway 8 Stationary flange 9 Support hole 10a, 10b Inner ring raceway 11 Rotating flange 12 Mounting Hole 13 Stud 14 Hub body 15 Inner ring 16 Small diameter cylinder 17 Stepped portion 18 Caulking portion 19 Cager 20 Pocket 21 Outer core metal 22a, 22b, 22c Seal lip 23 Outer seal material 24a, 24b Shoulder 25 Rolling element installation space 26, 26a, 26b, 26c Slinger 27, 27a, 27b Seal ring 28 Fitting cylinder part 29 Ring plate part 30 Core metal 31, 31a, 31b Seal material 32 Cylindrical part 33 Bent part 34 Base parts 35a, 35b, 35c Seal lip 36, 36a, 36b Labyrinth slip 37, 37a Base half part 38, 38a Front half part 39, 39a, 39b Fixed facing surface 40, 40a, 40b, 40c, 40d Rotation facing surface 41, 41a, 41b, 41c, 41d Labyrinth seal 42, 42a, 42b Eaves part 43, 43a, 43b Encoder 44, 44a Projection part 45, 45a Step surface 46, 46a Axial labyrinth seal 47, 47a Convex part 48, 48a, 48b Space 49 Coupling part 50 Extension base part 100 combination Seal ring 101 Slinger 102 Inner ring 104 Inner ring 104 Fitting cylinder part 105 Disc plate part 106 Core metal 107 Sealing material 108 Outer ring 109 Cylindrical part 110 Bent part 111 Base parts 112a, 112b, 112c Seal lip 113 Labyrinth lip 114 Labyrinth seal 115 Concave Groove 116 Foreign substance 117 Joining portion 118 Extending base portion

Claims (5)

A slinger having a fitting tubular portion and an annular plate portion bent outward in the radial direction from an axial end portion of the fitting tubular portion;
A core metal, and a seal ring having a seal material fixed to the core metal,
Equipped with
The sealing material is a base fixed to the core metal, and one or a plurality of seals extending from the base toward the surface of the slinger and having a tip portion slidably contacting the surface of the slinger over the entire circumference. Of the lip and the base portion, an extension base portion that is present on the outer side in the radial direction from the joint portion to which the base end portion of the seal lip on the outermost radial direction of the seal lip is joined, Having a labyrinth slip that includes a portion that extends toward the plate portion and radially outward,
By making the rotary facing surface provided on the slinger or another member fixed to the slinger and the fixed facing surface provided on the labyrinth slip closely face each other, the rotary facing surface and the fixed facing surface are In between, it constitutes a labyrinth seal,
The labyrinth slip is elastically deformed in a direction in which a gap between the fixed facing surface and the rotating facing surface becomes smaller with the relative rotation of the slinger and the seal ring.
Combination seal ring. The labyrinth slip has an outer peripheral surface or an inner peripheral surface, and has the fixed facing surface,
The slinger or another member fixed to the slinger has the rotation facing surface on a circumferential surface radially facing the fixed facing surface.
The combination seal ring according to claim 1. The labyrinth slip extends from the extending base portion toward the annular plate portion in the axial direction and extends radially outward, and bends from the tip end portion of the base half portion in the radial direction. It has a circular ring-shaped front half portion that extends toward the outside and a fixed facing surface provided on a side surface of the front half portion that is closer to the circular plate portion in the axial direction,
The slinger or another member fixed to the slinger is orthogonal to the central axis of the slinger, and has the rotation facing surface on a side surface axially facing the fixed facing surface,
The combination seal ring according to claim 1. The slinger or another member fixed to the slinger has a step surface facing inward in the radial direction over the entire circumference,
The facing area of the tip surface of the first half portion of the labyrinth slip and the step surface, relative to the state in which the seal ring and the slinger is not relatively rotating, relative to the seal ring and the slinger relative rotation Grows when you are
The combination seal ring according to claim 3. An outer ring member having an outer ring raceway on the inner peripheral surface,
An inner ring member having an inner ring raceway on the outer peripheral surface,
A plurality of rolling elements arranged between the outer ring raceway and the inner ring raceway,
A combination seal ring for closing an opening of an axial end portion of a rolling element installation space existing between an inner peripheral surface of the outer ring member and an outer peripheral surface of the inner ring member,
Equipped with
The combination seal ring is the combination seal ring according to any one of claims 1 to 4, wherein the fitting tubular portion of the slinger is externally fitted and fixed to an axial end portion of the inner ring member. Along with, the core metal of the seal ring is internally fitted and fixed to the axial end portion of the outer ring member,
Hub unit bearing.

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