JP2014129880A - Hub unit bearing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hub unit bearing comprising a side face cover having a drain hole which makes water hardly intrude to the inside from the drain hole without lowering the rigidity of the side face cover even if the water is splashed to the vicinity of the drain hole.SOLUTION: A side face cover 18 covering an axial end of a hub unit bearing 10 has a disc part 34 and a cylinder part 35 which is folded to an axial direction from an external peripheral edge of the disc part 34, and at the cylinder part 35 which is fittingly fixed to an outer ring member 11, there is formed a drain hole 42 which makes the inside and outside of the side face cover 18 communicate with each other by a cut-and-raised part 41 which is cut and raised toward the radial inside or radial outside of the cylinder part 35.

Description

  The present invention relates to a hub unit bearing, and more particularly to a hub unit bearing including a side cover that covers shaft end portions of an outer ring member and an inner ring member.

  2. Description of the Related Art Conventionally, a wheel bearing rolling bearing unit with an encoder in which a rotational speed detecting device is incorporated in a rolling bearing unit in order to detect the rotational speed of a wheel is known. In such a wheel-supporting rolling bearing unit with an encoder, a cover for separating the external space from the space where the encoder exists is mounted in order to prevent foreign matter from entering from the outside. The cover is provided with water drain holes for discharging water that has entered the vehicle during washing, muddy water that splashes from the road surface during rainy weather, and the like (for example, see Patent Documents 1 and 2).

JP 2005009525 A JP 2008-175382 A

  The cover of the rolling bearing unit described in Patent Documents 1 and 2 includes a cylindrical portion and an annular portion bent radially inward from the inner end edge of the cylindrical portion, and the cylindrical portion is fitted to the outer ring or the like. Fixed. The drain hole provided in the cover is a simple hole formed in the lower part of the cylindrical part, and has the function of discharging the water that has entered inside, but water is splashed in the vicinity of the drain hole during car washing, etc. On the contrary, there is a possibility that water may enter the inside through this drain hole. Moreover, depending on the position of the drain hole, there is a possibility that the strength of the fitting portion may be reduced, and there is room for improvement.

  The present invention has been made in view of the above-described problems, and its purpose is to prevent water from penetrating from the drainage hole even if water is splashed in the vicinity of the drainage hole without reducing the strength of the side cover. It is an object of the present invention to provide a hub unit bearing including a side cover having a water drain hole which is difficult to perform.

The above object of the present invention can be achieved by the following constitution.
(1) A hub unit bearing comprising an outer ring member, an inner ring member that is rotatable relative to the outer ring member via a plurality of rolling elements, and a side cover that covers end portions in the axial direction of the outer ring member and the inner ring member. The side cover includes a disk portion and a cylindrical portion that is bent in the axial direction from the outer peripheral edge portion of the disk portion and fitted and fixed to the outer ring member, and the cylindrical portion has a diameter of the cylindrical portion. It is provided with a cut-and-raised portion that is cut and raised toward the inside in the direction and formed with a water drain hole that communicates the inside and outside of the side cover. Cut and raised by two cutting lines formed along the circumferential direction, drain holes are formed on both sides in the axial direction of the cut-and-raised portion, and the end surface of the cut-and-raised portion in the axial direction is the end surface of the outer ring member The drain hole is on the radially inner side near the other axial end of the cylindrical portion. Hub unit bearing, characterized in that the mouth.
(2) A hub unit bearing comprising an outer ring member, an inner ring member that is rotatable relative to the outer ring member via a plurality of rolling elements, and a side cover that covers end portions in the axial direction of the outer ring member and the inner ring member. The side cover includes a disk portion and a cylindrical portion that is bent in the axial direction from the outer peripheral edge portion of the disk portion and fitted and fixed to the outer ring member, and the cylindrical portion has a diameter of the cylindrical portion. It is provided with a cut-and-raised portion that is cut and raised toward the inside in the direction and formed with a water drain hole that communicates the inside and outside of the side cover. It is cut and raised by a single cutting line formed along the circumferential direction, and one axial end side of the cut raised portion is continuous with the cylindrical portion, and the other axial end side is separated from the cylindrical portion to drain water. The drain hole is formed only on the other axial end of the cut and raised part. Is, the drain hole, the hub unit bearing, characterized in that the opening radially inside the axial end side of the cylindrical portion.
(3) The hub unit bearing according to (1) or (2), wherein the cut-and-raised portion is disposed within a range of 35 ° with respect to the normal of the side cover in a side view.
(4) The hub unit bearing according to any one of (1) to (3), wherein the hub unit bearing includes an encoder capable of detecting rotation of the inner ring member.

  According to the hub unit bearing of the present invention, it is provided with a side cover including a disk part and a cylindrical part bent in the axial direction from the outer peripheral edge part of the disk part, and the cylindrical part has a radially inner side of the cylindrical part, or A drainage hole that communicates the inside and outside of the side cover is provided by a cut-and-raised portion that is cut and raised radially outward. Since a part of the cut and raised portion is connected to the cylindrical portion, the strength of the cylindrical portion is maintained. Further, since the drain hole is not directly open to the outside, even if water is splashed in the vicinity of the drain hole, it is possible to effectively prevent water from entering from the outside.

Further, according to the hub unit bearing of the present invention, a part of the cylindrical portion is cut by two cutting lines formed along the circumferential direction so that the cut-and-raised portion is directed radially inward. The drainage hole is formed on both sides in the axial direction of the cut and raised part, the end surface on one end side in the axial direction of the cut and raised part contacts the end surface of the outer ring member, and the drainage hole is on the other end side in the axial direction of the cylindrical part Since it opens to the inner side in the radial direction, one of the two drain holes provided on both sides of the cut and raised portion is blocked by the outer ring member. Therefore, it is possible to further prevent water and the like from entering the side cover.
Further, according to the hub unit bearing of the present invention, the cut-and-raised portion is cut at one cutting line formed along the circumferential direction so that the cut-and-raised portion is directed radially inward. One end in the axial direction of the cut and raised portion is continuous with the cylindrical portion, and the other end in the axial direction is cut off from the cylindrical portion to form a drain hole, and the drain hole is the other end in the axial direction of the cut and raised portion. The drainage hole is formed only on the radial direction inner side near the other axial end side of the cylindrical portion, so that the drainage hole is formed only on one axial side of the cut and raised portion. Therefore, it is possible to further prevent water and the like from entering the side cover.

It is sectional drawing of 1st Embodiment of the hub unit bearing which concerns on this invention. It is an enlarged view of the A section of FIG. FIG. 3 is a cross-sectional view of the side cover shown in FIG. It is an expansion perspective view of the periphery of the drain hole of the side cover shown in FIG. It is the schematic which shows the phase of a drain hole. It is a principal part expanded sectional view of the 1st modification of the side cover of 1st Embodiment. It is a principal part expanded sectional view of the 2nd modification of the side cover of 1st Embodiment. It is a principal part expanded sectional view of the 3rd modification of the side cover of 1st Embodiment. It is a principal part expanded sectional view of the 4th modification of the side cover of 1st Embodiment. It is a principal part expanded sectional view of the 5th modification of the side cover of 1st Embodiment. It is sectional drawing of 2nd Embodiment of the hub unit bearing which concerns on this invention. (A) is a bottom view of the side cover shown in FIG. 11, (b) is a left side view of the side cover shown in FIG. It is a bottom view of the modification of the side cover of 2nd Embodiment. It is a principal part expanded sectional view of 3rd Embodiment of the hub unit bearing which concerns on this invention.

  Hereinafter, each embodiment of a hub unit bearing concerning the present invention is described in detail based on a drawing.

(First embodiment)
First, with reference to FIGS. 1-10, 1st Embodiment of the hub unit bearing which concerns on this invention is described.

  The hub unit bearing 10 of this embodiment is a hub unit bearing for driving wheels. As shown in FIG. 1, an outer ring member 11, a hub ring 12 that is an inner ring member, and a hub ring 12 that are formed as separate bodies. An inner ring 13 that is integrally fixed, balls 14 that are a plurality of rolling elements, sealing devices 15 and 16, a rotation detection sensor unit 17, and a side cover 18 are provided.

  The outer ring member 11 is fitted into a holding hole 26a of a knuckle 26 fixed to a vehicle body (not shown), and a suspension flange 11f provided on the outer peripheral surface of the outer ring member 11 is fastened to the knuckle 26 with a bolt 26b. It is fixedly coupled to the knuckle 26.

  The hub wheel 12 is a substantially columnar member, and a flange portion 12b is formed on the outboard side end portion (left side in the drawing) that extends radially outward from the outer peripheral surface. A plurality of hub bolts 19 for fastening a wheel, a brake rotor, and the like (not shown) are implanted in the flange portion 12b at substantially equal intervals in the circumferential direction. A spline groove 12e is formed on the inner peripheral surface of the hub wheel 12 to be splined with a spline shaft of a constant velocity joint (not shown).

  A small-diameter step portion 12d is formed on the inboard side end portion (right side in the figure) of the hub wheel 12, and after the inner ring 13 is fitted on the small-diameter step portion 12d, the end portion of the small-diameter step portion 12d is crimped. By doing so, the inner ring 13 is coupled and fixed to the hub ring 12. Further, an appropriate pressure is applied by pressing the inner ring 13 by caulking.

  Two rows of outer ring raceway surfaces 11a and 11a that are parallel to each other are formed on the inner circumferential surface of the outer ring member 11 apart from each other, and the inner ring raceway surfaces 12a and 13a are formed on the outer circumferential surfaces of the hub ring 12 and the inner ring 13, respectively. Is formed corresponding to each outer ring raceway surface 11 a of the outer ring member 11. A plurality of balls 14, which are rotatably held by a cage 20, are arranged at equal intervals in the circumferential direction on the track constituted by the inner ring raceway surfaces 12 a and 13 a and the outer ring raceway surfaces 11 a and 11 a.

  The plurality of balls 14 are in contact with the outer ring raceway surfaces 11a and 11a and the inner ring raceway surfaces 12a and 13a at a predetermined angle to form a back-side combination (DB) bearing. As a result, the hub wheel 12 can rotate about the axis CL with respect to the outer ring member 11.

  Further, a sealing device 15 is provided between the end portion on the outboard side of the outer ring member 11 and the hub wheel 12, and a sealing device 16 is provided between the end portion on the inboard side of the outer ring member 11 and the inner ring 13. Provided. As a result, both end portions in the axial direction of the bearing space 25 of the hub unit bearing 10 are sealed to prevent the enclosed grease from leaking to the outside, and various foreign matters such as rainwater, mud, dust, etc. existing outside the bearing. Intrusion into the space 25 is prevented.

  The sealing device 16 includes an L-shaped cored bar 23 that is press-fitted and fixed to the inner peripheral surface 11 c of the inboard side end of the outer ring member 11, and an elastic seal part that is formed by rubber or the like attached to the cored bar 23. 24 and a slinger 30 that is press-fitted and fixed to the outer peripheral surface 13b of the inner ring 13 and that the three seal lips 24a of the elastic seal portion 24 are in sliding contact with.

  The rotation detection sensor unit 17 includes an encoder 31 attached to the side surface of the slinger 30 and a sensor 32 in which a detection unit 32a is disposed close to the detected surface 31a of the encoder 31. The encoder 31 is made of a rubber magnet or plastic magnet in which a ferromagnetic material such as ferrite or rare earth element is mixed in rubber or synthetic resin, and is magnetized. The magnetization direction changes alternately at equal intervals in the circumferential direction.

  The side cover 18 is formed by pressing a corrosion-resistant metal plate such as a stainless steel plate or a galvanized steel plate, and a disk having a through hole 33 through which a spline shaft of a constant velocity joint (not shown) is inserted at the center. And a small-diameter cylindrical portion 35 and a large-diameter cylindrical portion 36 that are bent in two stages in the axial direction from the outer peripheral edge of the disk portion 34. The large-diameter cylindrical portion 36 is fitted on the outer peripheral surface 11 d of the outer ring member 11, and a step portion 37 between the small-diameter cylindrical portion 35 and the large-diameter cylindrical portion 36 abuts on the inner end surface 11 e of the outer ring member 11.

  As shown in FIGS. 2 to 4, the small-diameter cylindrical portion 35 is cut along two cutting lines 40 and 40 set in parallel along the circumferential direction of the small-diameter cylindrical portion 35. A cut-and-raised portion 41 cut and raised toward the inside in the radial direction is formed. The cut-and-raised part 41 is cut and raised from the small-diameter cylindrical part 35 into a band shape and is formed in a substantially trapezoidal cross section. Both ends in the circumferential direction of the cut and raised portion 41 are continuous with the small diameter cylindrical portion 35, and both sides in the axial direction are separated from the small diameter cylindrical portion 35. As a result, drain holes 42 are formed on both sides in the axial direction of the cut-and-raised portion 41 to communicate the inside and outside of the side cover 18.

  The sensor 32 is inserted through a sensor hole 43 formed in the small-diameter cylindrical portion 35 of the side cover 18, and the detection portion 32 a is disposed to face the detected surface 31 a of the encoder 31. When the encoder 31 rotates together with the hub wheel 12 and the inner ring 13, the output of the sensor 32 changes at a frequency proportional to the rotation speed, so that the rotation speed of a wheel (not shown) is detected.

  As shown in FIG. 5, it is preferable that the water drain hole 42 is disposed at a position D immediately below the radial direction and a position A1 of 10 to 35 ° in the rotational direction when the vehicle moves forward from the vertical line VL. Here, the position D is a position where water is easily discharged by gravity when the vehicle is stationary, and the position A1 is suitable for discharging water splashed by the rotation of the encoder 31 when the vehicle travels forward. Position.

  In general, since the vehicle is mostly driven forward, it is preferable to provide the drain holes 42 at the positions D and A1 described above. However, the side cover 18 is shared by the left and right wheels. Alternatively, if the rotational direction of the bearing 10 at the time of forward movement cannot be specified due to management reasons, the drain holes 42 are also arranged at a position A2 that is symmetrical to the position A1 with respect to the vertical line VL so that a total of three locations are provided. May be. The number of drain holes 42 is arbitrary and may be four or more.

  Furthermore, in the bearing used for a normal passenger vehicle and a freight vehicle, it is preferable to provide in a total of two places of the position D mentioned above and the position of 6-12 degrees of the rotation direction at the time of a vehicle advance from the perpendicular VL. Here, the reason why the angle is 6 to 12 ° is that the acceleration / deceleration of a car that performs gentle driving on a flat road is usually about 0.1 to 0.2 G. It is because it set to the range of 0.1-0.2.

  In vehicles that often run on rough roads, taking into account the momentary acceleration / deceleration and vehicle posture, it is at a larger angle, for example, 20-30 °, on rough terrain, and at a relatively low speed. In civil engineering, agricultural vehicles, or four-wheel drive vehicles, where the ratio of traveling and forward / backward travel is often close to each other, one position is located at 10-25 ° on both sides from the position D and the vertical line VL. It is preferable to provide a total of three cylinders. Furthermore, when providing a water drain hole at an angle of 6 to 12 °, a plurality of water drain holes can be formed instead of a plurality of water drain holes.

  In addition, as shown in FIG. 3, the circumferential length L per drainage hole 42 is preferably 4 to 10 times the material plate thickness t. This is because it is difficult to cut and raise when the circumferential length L is 4 times or less the plate thickness t, and when it exceeds 10 times, the cut and raised portion 41 reduces the rigidity of the small diameter cylindrical portion 35. This is because it is difficult to maintain an appropriate slit width and the strength of the small diameter cylindrical portion 35 may be affected. Furthermore, in the case where a plurality of drain holes 42 are provided, the total length L of the drain holes 42 may be 5 to 10% of the outer circumferential length of the small diameter cylindrical portion 35 for strength reasons. preferable.

  Moreover, as shown in FIG. 3, although the height H of the drain hole 42 is arbitrary, it is preferable to set it as 0.5 mm or more and board thickness t or less. If the thickness is less than 0.5 mm, sufficient draining effect may not be obtained due to the interfacial tension of water. If the thickness exceeds t, not only processing becomes difficult, but the opening area is large. This is because the possibility of the intrusion of foreign matter increases.

  Further, as shown in FIG. 2, it is preferable in terms of processing that the axial width W of the cut and raised portion 41 is not less than twice the plate thickness t. For the same reason, the gap C between the inboard side end surface of the cut and raised portion 41 and the inner surface of the disk portion 34 needs to be processed with a separation of at least twice the plate thickness t. If the gap C is too small, there is a possibility that a sufficient draining effect cannot be obtained due to the interfacial tension of water.

  The material of the side cover 18 is preferably a nonmagnetic material such as austenitic stainless steel. If it is austenitic stainless steel, it is possible to form the cut and raised by pressing, etc., and the wear powder magnetized by mechanical force, sand iron, dust on the road surface, etc. are held by magnetic force Nor. Further, the shape of the cut-and-raised portion 41 is arbitrary, and is not limited to the cross-sectional trapezoidal shape shown in FIG. 3, and may be, for example, a cross-sectional triangle shape or a cross-sectional arc shape.

  As described above, according to the hub unit bearing 10 of the present embodiment, the water that has entered the inside of the side cover 18 can be effectively discharged from the drain hole 42 provided in the lower part of the side cover 18. Further, unlike the conventional drainage hole, the drainage hole 42 is closed with a belt-like cut and raised portion 41, so even if water or the like is splashed outside in the vicinity of the drainage hole 42, Intrusion into the side cover 18 can be prevented.

  Further, according to the hub unit bearing 10 of the present embodiment, the side cover 18 includes the disk portion 34 and the small-diameter cylindrical portion 35 and the large-diameter cylindrical portion 36 that are bent in the axial direction from the outer peripheral edge portion of the disk portion 34. Since the cut-and-raised part 41 is formed in the small-diameter cylindrical part 35 and is cut and raised toward the inside in the radial direction, and part of the small-diameter cylindrical part 35 is connected to the small-diameter cylindrical part 35. The strength of the small diameter cylindrical portion 35 is maintained. Further, since the drain hole 42 is not directly open to the outside, even if water is splashed in the vicinity of the drain hole 42, it is possible to effectively prevent water from entering from the outside.

(First modification)
As a first modification of the present embodiment, the side cover 18 may be a side cover 18A shown in FIG. In the side cover 18A, there is one cylindrical portion 35, and the cut-and-raised portion 41 is formed in the cylindrical portion 35 toward the inside in the radial direction. The side cover 18 </ b> A is assembled such that the cylindrical portion 35 is fitted on the outer peripheral surface 11 d of the outer ring member 11, and the left end surface of the cut and raised portion 41 is in contact with the inner end surface 11 e of the outer ring member 11.

  According to this modified example, one of the two drain holes 42 provided on both sides of the cut and raised portion 41 (the left side in the figure) is closed by the outer ring member 11, It is possible to further prevent water or the like from entering the cover 18A.

(Second modification)
As a second modification of the present embodiment, the side cover 18 may be a side cover 18B shown in FIG. In the side cover 18B, the cut-and-raised portion 41 is formed outward in the radial direction.

(Third Modification)
As a third modification of the present embodiment, the side cover 18 may be a side cover 18C shown in FIG. In the side cover 18C, a part of the small-diameter cylindrical portion 35 is cut by a single cutting line 40C formed along the circumferential direction at a position close to the disk portion 34, and cut toward the radially inner side. Thus, a cut-and-raised portion 41C having a substantially L-shaped cross section is formed in the small diameter cylindrical portion 35. Accordingly, one end side in the axial direction (left side in the figure) of the cut-and-raised part 41C is continuous with the small diameter cylindrical part 35, and the other end side in the axial direction (right side in the figure) is separated from the small diameter cylindrical part 35. Is formed.

  According to this modification, the drain hole 42 is formed only on one axial side (right side in the drawing) of the cut and raised portion 41C, so that it is possible to further prevent water and the like from entering the side cover 18C. .

(Fourth modification)
As a fourth modification of the present embodiment, the side cover 18 may be a side cover 18D shown in FIG. In the side cover 18D, a part of the small diameter cylindrical portion 35 is cut at one cutting line 40D formed along the circumferential direction at a position close to the disk portion 34, and is cut and raised toward the radially inner side. Thus, a cut-and-raised portion 41D having a substantially U-shaped cross section is formed in the small diameter cylindrical portion 35. Therefore, one end side in the axial direction (left side in the figure) of the cut-and-raised part 41D is continuous with the small diameter cylindrical part 35, and the other end side in the axial direction (right side in the figure) is separated from the small diameter cylindrical part 35. Is formed.

  According to the present modification, the drain hole 42 is formed only on one side in the axial direction of the cut and raised portion 41D (right side in the figure), so that intrusion of water or the like into the side cover 18D can be further prevented. .

(5th modification)
As a fifth modification of the present embodiment, the side cover 18 may be a side cover 18E shown in FIG. In the side cover 18E, a part of the small diameter cylindrical portion 35 is cut by a single cutting line 40E formed along the circumferential direction at a position separated from the disk portion 34, and cut toward the outside in the radial direction. Thus, a cut-and-raised portion 41E having a substantially U-shaped cross section is formed in the small diameter cylindrical portion 35. Accordingly, one end side in the axial direction (right side in the figure) of the cut-and-raised part 41E is continuous with the small diameter cylindrical part 35, and the other end side in the axial direction (left side in the figure) is separated from the small diameter cylindrical part 35. Is formed.

  According to this modification, since the drain hole 42 opens toward the inner side in the axial direction, it is possible to further prevent water and the like from entering the side cover 18E.

(Second Embodiment)
Next, a second embodiment of a hub unit bearing according to the present invention will be described with reference to FIGS. Note that portions that are the same as or equivalent to those of the first embodiment are denoted by the same reference numerals in the drawings, and description thereof is omitted or simplified.

  As shown in FIG. 11, the hub unit bearing 10 </ b> A of the present embodiment is a driven wheel hub unit bearing, and is formed separately from the outer ring member 11, the hub ring 12 that is the inner ring member, and is integrated with the hub ring 12. The inner ring 13 is fixed, the balls 14 which are a plurality of rolling elements, the sealing devices 15 and 16, and the side cover 50 are provided.

  The side cover 50 includes a disk part 51 and a cylindrical part 52 that is bent from the outer peripheral edge of the disk part 51 in the axial direction. A flange portion 53 that protrudes radially outward is provided in the middle of the cylindrical portion 52 in the axial direction. The flange portion 53 is brought into contact with the inner end surface 11e of the outer ring member 11 so that the inner ring member 11 has an inner surface. It is fitted and fixed to the peripheral surface 11c.

Also, as shown in FIGS. 11 and 12, a groove portion 54 having a substantially semicircular cross section that is recessed radially inward is formed on the distal end side (left side in FIG. 11) of the cylindrical portion 52 of the side cover 50. Yes.
The groove portion 54 is substantially parallel to the axis of the side cover 50 and is formed to an axial position slightly beyond the flange portion 53. Accordingly, as shown in FIG. 12A, the flange portion 53 is curved in the direction of the disk portion 51 at the groove portion 54.

  When the side cover 50 is fitted into the inner peripheral surface 11c of the outer ring member 11, an approximately L-shaped axial section is provided between the groove 54 and the inner peripheral surface 11c and the inner end surface 11e of the outer ring member 11. A tunnel-shaped drain hole 55 is formed.

  In the present embodiment, it is preferable that the circumferential width P of the drain hole 55 (groove 54) is 4 to 10 times the material thickness t. This is because if the circumferential width P is 4 times or less of the material thickness t, it is difficult to process the groove portion 54 and there is a possibility that a sufficient draining effect cannot be obtained due to the interfacial tension of water, etc. Moreover, when it exceeds 10 times, it is because the intensity | strength of the cylindrical part 52 may come out.

  In addition, although the cross-sectional shape of the groove part 54 of this embodiment is a substantially semicircle shape, the cross-sectional shape is arbitrary. However, in consideration of drainage performance and workability, the height of the water passage portion is preferably 0.5 mm or more and the plate thickness t or less. Further, the arrangement position and the arrangement location of the groove portion 54 in the circumferential direction are the same as those in the first embodiment.

  In the side cover 50 according to the present embodiment, since the cylindrical portion 52 is not cut, the possibility of affecting the strength of the cylindrical portion 52 is further reduced. Therefore, after the side cover 50 is plastically processed into a bottomed annular shape and coated on the entire surface, the groove portion 54 is molded to allow application of a material that easily rusts. Furthermore, since it has a relatively simple shape, it can be easily painted after the groove portion 54 is molded.

  Further, in the case of the hub unit bearing 10A that does not include an encoder as in this embodiment, the drainage performance is ensured by forming the side cover 50 with an inexpensive material such as SPCC steel plate and painting it, and the side surface It is possible to prevent the cover 50 from being rusted. Further, as the coating, electrodeposition coating or baking coating is preferable. Further, instead of painting, electroless nickel plating, chromium plating, zinc plating, tin plating, or a combination thereof is also possible.

As described above, according to the hub unit bearing 10A of the present embodiment, the groove portion 54 formed in a concave shape toward the radially inner side of the cylindrical portion 52 is formed in the cylindrical portion 52 of the side cover 50 along the axial direction. When the cylindrical portion 52 is fitted to the outer ring member 11, a tunnel-like drain hole 55 is formed between the cylindrical portion 52 and the outer ring member 11. Therefore, the cylindrical portion 52 has no cutting portion and the cylindrical portion 52. Strength can be maintained. Moreover, since the drain hole 55 is not directly open to the outside, even if water is splashed in the vicinity of the drain hole 55, it is possible to effectively prevent water from entering from the outside. Furthermore, since there is no cutting process, rust prevention treatment such as painting is easy, and rust prevention performance can be enhanced.
About another structure and an effect, it is the same as that of the said 1st Embodiment.

(Modification)
As a modification of this embodiment, the side cover 50 may be a side cover 50A shown in FIG. In the side cover 50A, the groove portion 54 formed in the cylindrical portion 52 is formed to be inclined by a predetermined angle α with respect to the axis of the side cover 50A. In this case, by inclining the groove 54 in the same direction as the rotation direction of the hub unit bearing 10A, water can be easily discharged by rotation, and drainage performance can be improved.

(Third embodiment)
Next, a third embodiment of the hub unit bearing according to the present invention will be described with reference to FIG. Note that portions that are the same as or equivalent to those of the first embodiment are denoted by the same reference numerals in the drawings, and description thereof is omitted or simplified.

  In the hub unit bearing 10 of the present embodiment, as shown in FIG. 14, a side cover 60 shown in FIG. 14 is used instead of the side cover 18 of the first embodiment. The side cover 60 has a large-diameter cylindrical portion 61 that is fitted on the outer peripheral surface 11 d of the outer ring member 11, and extends radially inward from an inboard side end portion of the large-diameter cylindrical portion 61, and is formed on the inner end surface 11 e of the outer ring member 11. A stepped portion 62 that contacts, a small-diameter cylindrical portion 63 that extends from the inner peripheral edge of the stepped portion 62 toward the axial inboard side, a disk portion 64 that extends radially inward from the inboard-side end of the small-diameter cylindrical portion 63, and a disk An inner peripheral cylindrical portion 65 extending from the inner peripheral edge of the portion 64 toward the axial outboard side. In the side cover 60, the cut-and-raised portion 41 is formed in the small-diameter cylindrical portion 63 toward the radially inner side.

  In the present embodiment, a sealing device 70 is provided between the small-diameter outer peripheral surface 13 c formed at the inboard side end of the inner ring 13 and the inner peripheral surface of the inner peripheral cylindrical portion 65 of the side cover 60. Yes. The sealing device 70 includes an L-shaped cored bar 71 that is press-fitted and fixed to the small-diameter outer peripheral surface 13 c of the inner ring 13, and a seal lip 72 a that is attached to the cored bar 71 and is in sliding contact with the inner peripheral surface of the inner peripheral cylindrical portion 65. And an elastic seal portion 72 having Thereby, invasion of various foreign substances into the side cover 60 is prevented. The seal lip 72 a is not limited to the contact type that contacts the inner peripheral cylindrical portion 65 described above, and may be a non-contact type that forms a slight gap with the inner peripheral cylindrical portion 65.

10 Hub unit bearing 11 Outer ring member 12 Hub ring (inner ring member)
14 balls (rolling elements)
18 Side cover 18A Side cover 18B Side cover 18C Side cover 18D Side cover 18E Side cover 31 Encoder 34 Disk part 35 Small diameter cylindrical part (cylindrical part)
40 cutting line 40C cutting line 40D cutting line 40E cutting line 41 cut and raised part 41C cut and raised part 41D cut and raised part 41E cut and raised part 42 drain hole 10A hub unit bearing 50 side cover 50A side cover 51 disk part 52 cylindrical part 54 groove part 55 Drain hole 60 Side cover 63 Small diameter cylindrical part (cylindrical part)
64 Disc part VL Side cover perpendicular

Claims (4)

A hub unit bearing comprising: an outer ring member; an inner ring member that is rotatable relative to the outer ring member via a plurality of rolling elements; and a side cover that covers the outer ring member and an axial end of the inner ring member. Because
The side cover has a disk part, and a cylindrical part that is bent and formed in an axial direction from an outer peripheral edge part of the disk part and fitted and fixed to the outer ring member,
The cylindrical portion includes a cut-and-raised portion that is cut and raised toward the inside in the radial direction of the cylindrical portion, and is formed with a drain hole that communicates the inside and outside of the side cover.
A part of the cylindrical part is cut and raised by two cutting lines formed along the circumferential direction so that the cut-and-raised part faces radially inward, and the axis of the cut-and-raised part The drain holes are formed on both sides in the direction,
The end surface on the one end side in the axial direction of the cut and raised portion abuts on the end surface of the outer ring member,
The hub unit bearing according to claim 1, wherein the drain hole is opened radially inward of the cylindrical portion near the other axial end. A hub unit bearing comprising: an outer ring member; an inner ring member that is rotatable relative to the outer ring member via a plurality of rolling elements; and a side cover that covers the outer ring member and an axial end of the inner ring member. Because
The side cover has a disk part, and a cylindrical part that is bent and formed in an axial direction from an outer peripheral edge part of the disk part and fitted and fixed to the outer ring member,
The cylindrical portion includes a cut-and-raised portion that is cut and raised toward the inside in the radial direction of the cylindrical portion, and is formed with a drain hole that communicates the inside and outside of the side cover.
The cut-and-raised part is cut and raised by a single cutting line formed along the circumferential direction so that the cut-and-raised part is directed radially inward. One end side in the direction is continuous with the cylindrical portion, and the other end side in the axial direction is separated from the cylindrical portion to form the drain hole,
The drain hole is formed only on the other axial end side of the cut and raised part,
The hub unit bearing according to claim 1, wherein the drain hole is opened radially inward of the cylindrical portion near the other axial end.   3. The hub unit bearing according to claim 1, wherein the cut-and-raised portion is disposed within a range of 35 ° with respect to the perpendicular of the side cover in a side view.   The hub unit bearing according to any one of claims 1 to 3, wherein the hub unit bearing includes an encoder capable of detecting rotation of the inner ring member.

Images