JP2008222151A - Rolling bearing device for wheel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rolling bearing device for a wheel having a constitution for preventing chips generated when press-fitting a hub bolt into a bolt hole of a flange from being discharged from the bolt hole. <P>SOLUTION: The rolling bearing device for wheel has an outer member and an inner member which are relatively turned via a rolling element, a bolt hole 4b is formed in a flange 4a formed on any one of the outer member and the inner member, and a wheel is attached to the hub bolt 7 press-fitted to the bolt hole 4b. The hub bolt 7 comprises a screw shaft part 7e having a male screw, a serration part 7b provided between the screw shaft part 7e and a bolt head part 7a and having a serration thereon, and an elastic body 7f provided on an outer circumference at the position between the serration part 7b and the screw shaft part 7e. The elastic body 7f is located in the bolt hole 4b to prevent chips generated by the press-fitting of the serration part 7b in the bolt hole 4b from being discharged to the screw shaft part 7e side. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a wheel rolling bearing device. More particularly, the present invention relates to a wheel rolling bearing device in which a hub bolt for mounting a wheel is press-fitted into a bolt hole formed in a flange.

2. Description of the Related Art Conventionally, a wheel rolling bearing device has an outer member and an inner member that rotate relative to each other via a rolling element, and a flange on which a wheel is mounted on either the outer member or the inner member. Is formed. A plurality of bolt holes are formed in the flange, and a hub bolt is press-fitted into each bolt hole (for example, Patent Document 1). At the time of press-fitting work, a hub bolt is press-fitted into the bolt hole after the flange is installed on the jig. Since the hub bolt has a serration, the hole wall surface of the bolt hole is cut by the serration to generate debris (varicus). When the wheel rolling bearing device is lifted from the jig, the scrap sometimes falls on the jig. When a flange of another rolling bearing device is installed on the jig and a hub bolt is press-fitted, the flange may be damaged or deformed by scraps falling on the jig. If the flange is deformed, the brake disc attached to the flange may be inclined, causing noise and vibration during braking. In order to prevent this, it is possible to consider a method in which the dust that has fallen on the jig is blown off with air each time. However, if this method is adopted, the manufacturing process becomes complicated.
JP-A-3-157202

  Then, this invention makes it a subject to provide the rolling bearing apparatus for wheels provided with the structure which prevents that the waste generated when a hub bolt is press-fitted in the bolt hole of a flange is discharged | emitted from a bolt hole.

  In order to solve the above-mentioned problems, the present invention is a rolling bearing device for a wheel having a configuration as described in each claim. That is, according to the first aspect of the present invention, the hub bolt includes a screw shaft portion in which a male screw is formed, a serration portion provided between the screw shaft portion and the bolt head portion and formed in serration, and a serration portion. And an elastic body provided on the outer periphery at a position between the screw shaft portions. The elastic body is configured to prevent the waste generated by press-fitting into the bolt hole of the serration part from being discharged into the screw shaft part side within the bolt hole.

  Therefore, the hub bolt retains the elastic body and the serration portion in the bolt hole. The scrap generated by scraping the hole wall surface of the bolt hole by the serration portion is prevented from being discharged to the screw shaft portion side by the elastic body. Therefore, it is possible to prevent scraps from falling on the jig used at the time of press-fitting the hub bolt, and the flanges from being damaged or deformed by the scraps. Alternatively, it is possible to prevent debris from adhering to the flange and mounting the brake rotor or the like in a state where the debris is inclined to the flange.

  According to invention of Claim 2, an elastic body is a resin-made tape or a resin-made tube. Therefore, the elastic body can be easily attached to the outer peripheral surface of the hub bolt. For example, in the case of a resin tape, the tape is attached by being wound around the outer peripheral surface of the hub bolt. In the case of a resin tube, the tube is attached by being press-fitted into the outer peripheral surface of the hub bolt.

  An embodiment of the present invention will be described with reference to FIGS. As shown in FIG. 1, the wheel rolling bearing device 1 includes an outer member 2, an inner member 3, and rolling elements 6. The outer member 2 has a mounting flange 2a on the outer peripheral portion and two rows of raceway surfaces 2b on the inner peripheral surface. The mounting flange 2a is fixed to a knuckle which is a member on the vehicle body side.

  The inner member 3 includes a hub shaft 4 and an inner ring 5 as shown in FIG. The hub shaft 4 has a cylindrical shape, and has a flange 4a on the outer peripheral surface at one end and a recess 4c on the outer peripheral surface of the other end. The inner ring 5 is fitted in the recess 4c, and is integrated with the hub axle 4 by a caulking portion 4d that caulks one end of the hub axle 4. On the outer peripheral surface of the hub shaft 4 and the outer peripheral surface of the inner ring 5, raceway surfaces 4e and 5a are formed. Between the raceway surfaces 4e and 5a and each raceway surface 2b of the outer member 2, a plurality of rolling elements 6 are provided so as to roll. The plurality of rolling elements 6 in each row are held by the holder 8 at a predetermined interval in the circumferential direction.

  The flange 4a is formed over the entire circumference of one end of the hub shaft 4, and bolt holes 4b are formed at predetermined intervals in the circumferential direction. The bolt hole 4b penetrates the flange 4a in the axial direction, and the hub bolt 7 is press-fitted and fixed to each bolt hole 4b. The hub bolt 7 protrudes from the flange 4a to the vehicle outer side, and the brake rotor 10 and the wheel 11 are engaged with each other. A nut 12 is screwed onto the hub bolt 7, and the brake rotor 10 and the wheel 11 are fixed to the flange 4 a by the nut 12.

  As shown in FIG. 2, the hub bolt 7 has a bolt head portion 7a, a serration portion 7b, a cylindrical portion 7c, a taper portion 7d, and a screw shaft portion 7e in this order in the axial direction. As shown in FIG. 3, the bolt head 7a has a diameter larger than that of the bolt hole 4b, and is in contact with the back surface of the flange 4a. The serration portion 7b has serrations on the outer peripheral surface, and is press-fitted into the bolt hole 4b. The serration has a plurality of teeth having a spire-shaped cross section in the circumferential direction, and each tooth extends over the entire axial length of the serration portion 7b. The outermost diameter of the serration portion 7b is a diameter that is press-fitted into the bolt hole 4b with a predetermined press-fitting allowance. That is, it is slightly larger than the inner peripheral diameter of the bolt hole 4b. Accordingly, the serration portion 7b is press-fitted into the bolt hole 4b while cutting the hole wall surface of the bolt hole 4b.

  The cylindrical part 7c has a circular cross section as shown in FIG. The diameter of the cylindrical portion 7c is smaller than the outer diameter of the serration portion 7b and the inner diameter of the bolt hole 4b, and larger than the diameter of the male thread formed on the screw shaft portion 7e. And the elastic body 7f is attached to the outer peripheral surface of the cylindrical part 7c, as shown in FIG. As shown in FIG. 2, the diameter of the tapered portion 7d gradually decreases from the cylindrical portion 7c toward the screw shaft portion 7e. The screw shaft portion 7e has a male screw formed on the outer peripheral surface, and the nut 12 is screwed as shown in FIG.

  The elastic body 7f is made of an elastic material such as resin or rubber, and is, for example, a resin tape such as a seal tape or a resin tube (see FIG. 3). In the case of a tape, it is formed in a cylindrical shape by being wound around the outer peripheral surface of the columnar portion 7c. In the case of a tube, it is formed in a cylindrical shape in advance and is press-fitted into the outer peripheral surface of the columnar portion 7c. The outer diameter of the elastic body 7f is substantially the same as the inner diameter of the bolt hole 4b. Preferably, it is slightly larger than the inner diameter of the bolt hole 4b and is press-fitted into the bolt hole 4b while being elastically deformed. Therefore, the elastic body 7f closes the bolt hole 4b by staying in the bolt hole 4b.

  As shown in FIG. 4, when the hub bolt 7 is press-fitted into the bolt hole 4b, a jig 9 is used. First, the wheel rolling bearing device 1 is set on the jig 9 so that the surface of the flange 4 abuts against the surface 9 a of the jig 9. Next, the hub bolt 7 is press-fitted into the bolt hole 4b of the flange 4a. At this time, a part of the hole wall surface of the bolt hole 4b is scraped by the serration portion 7b to generate scraps (varicus).

  However, the tip of the bolt hole 4b is closed by the elastic body 7f. Therefore, the waste is prevented from being discharged to the screw shaft portion 7e side by the elastic body 7f. Therefore, when the rolling bearing device 1 is lifted, scraps are prevented from falling on the surface 9a of the jig 9. Then, the flange 4a of the rolling bearing device 1 installed on the jig 9 can be prevented from being damaged or deformed by debris remaining on the jig 9.

  Further, as shown in FIG. 2, the elastic body 7f is prevented from moving to the serration portion 7b side by a step 7c1 formed between the cylindrical portion 7c and the serration portion 7b. Accordingly, the step 7c1 prevents the elastic body 7f from being displaced when the hub bolt 7 is press-fitted into the bolt hole 4b.

  The wheel rolling bearing device 1 is formed as described above. That is, as shown in FIG. 3, the hub bolt 7 includes a screw shaft portion 7e formed with a male screw, a serration portion 7b provided between the screw shaft portion 7e and the bolt head portion 7a and formed with serrations, and a serration portion. 7b and an elastic body 7f provided on the outer periphery at a position between the screw shaft portion 7e. The elastic body 7f is located in the bolt hole 4b and is configured to prevent the waste generated by press-fitting the serration portion 7b into the bolt hole 4b from being discharged to the screw shaft portion 7e side.

  Therefore, the hub bolt 7 retains the elastic body 7f and the serration portion 7b in the bolt hole 4b. And the waste produced by scraping the hole wall surface of the bolt hole 4b by the serration portion 7b is prevented from being discharged to the screw shaft portion 7e side by the elastic body 7f. Therefore, as shown in FIG. 4, it is possible to prevent scraps from falling on the jig 9 used when the hub bolt 7 is press-fitted and the flange 4a to be damaged or deformed by the scraps. Alternatively, it is possible to prevent scraps from adhering to the flange 4a and mounting the brake rotor 10 or the like in a state where the brake rotor 10 or the like is inclined to the flange 4a.

  The elastic body 7f is a resin tape or a resin tube. Therefore, the elastic body 7 f can be easily attached to the outer peripheral surface of the hub bolt 7. For example, in the case of a resin tape, the tape is attached by being wound around the outer peripheral surface of the hub bolt 7. In the case of a resin tube, the tube is attached by being press-fitted into the outer peripheral surface of the hub bolt 7.

(Other embodiments)
The present invention is not limited to the above-described embodiment, and may be the following form.
(1) The elastic body 7f of the above-described embodiment is provided on the outer peripheral surface of the cylindrical portion 7c having a circular cross section as shown in FIG. However, instead of the cylindrical portion 7c, the cross section may have a non-circular portion, for example, a polygonal portion, and an elastic body may be attached to the outer peripheral surface thereof.
(2) In the rolling bearing device 1 for a wheel according to the above embodiment, as shown in FIG. 1, the outer member 2 is fixed to the vehicle body side, the inner member 3 rotates, and the wheel 11 is attached to the inner member 3. It was a form to be worn. However, the inner member is fixed to the vehicle body side, the outer member is rotated via a rolling element provided on the outer periphery of the inner member, and a flange on which the wheel is mounted is formed on the outer member. There may be.
(3) The diameter of the cylindrical part 7c of the above embodiment is larger than the diameter of the male thread formed on the screw shaft part 7e as shown in FIG. However, it may be smaller than the diameter of the male thread.
(4) The elastic body 7f of the above embodiment has a cylindrical shape and a rectangular cross section. However, an O-ring having a circular cross section may be used.

It is sectional drawing of the rolling bearing apparatus for wheels. It is a front view of a hub bolt. They are a partial cross-sectional view of the flange near the bolt hole and a front view of the hub bolt. It is sectional drawing of the rolling bearing apparatus for wheels, and a jig | tool.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Rolling bearing apparatus 2 for wheels 2 ... Outer member 2a ... Mounting flange 3 ... Inner member 4 ... Hub shaft 4a ... Flange 4b ... Bolt hole 5 ... Inner ring 6 ... rolling element 7 ... hub bolt 7a ... bolt head 7b ... serration part 7c ... cylindrical part 7d ... taper part 7f ... elastic body 7e ... screw shaft part 9 ... Jig 10 ... Brake rotor 11 ... Wheel 12 ... Nut

Claims (2)

It has an outer member and an inner member that rotate relative to each other via a rolling element, and a bolt hole is formed in a flange formed on one of the outer member and the inner member, and is pressed into the bolt hole. A rolling bearing device for a wheel in which a wheel is mounted on a hub bolt,
The hub bolt includes a screw shaft portion on which a male screw is formed, a serration portion provided between the screw shaft portion and the bolt head portion and formed with serration, and a position between the serration portion and the screw shaft portion. An elastic body provided on the outer periphery,
The elastic body is configured to prevent the waste generated by press-fitting the serration portion into the bolt hole located in the bolt hole from being discharged to the screw shaft portion side. Rolling bearing device. It is a rolling bearing device for wheels according to claim 1,
A rolling bearing device for a wheel, wherein the elastic body is a resin tape or a resin tube.

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