JP2007327587A - Wheel bearing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wheel bearing device that avoids an interference with a brake component without deteriorating rigidity. <P>SOLUTION: The wheel bearing device is provided with: a hub ring 31 which has a flange 34 extended diametrally outward; and a bearing structure part 32 externally fitted to the hub ring 31. A notched part 53 for preventing the interference with the brake component is provided on a part of the outward-diametral face 52a of an outer member 36 of the bearing structure part 32. The notched part 53 is composed of a flat part 54 formed on the outward-diametral face 52a of the outer member 36 of the bearing structure part 32. The notched part 53 is formed by forging. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a wheel bearing device.

  In the wheel bearing device, a pair of inner rings is mounted (press-fitted) on the hub ring (called a first generation or second generation), and a raceway surface (rolling surface) is directly formed on the outer periphery of the hub ring. (Also called the third generation), and those in which the raceway surface (rolling surface) is formed directly on the outer circumference of the outer joint member of the hub wheel and the constant velocity universal joint (the fourth generation). .

  For example, a wheel bearing device called a third generation is described in Patent Document 1, and as shown in FIG. 3, such a wheel bearing device includes a hub wheel 1 having a flange 4 extending in the outer diameter direction, and a hub. And a bearing structure portion 2 fitted on the ring 1. The hub wheel 1 includes a shaft portion 3 and the flange 4 protruding from the shaft portion 3.

  The bearing structure portion 2 includes a ball 5 as a rolling element, an outer member (outer ring) 6 disposed on the outer peripheral side of the shaft portion 3 of the hub wheel 1 via the ball 5, and a shaft portion of the hub wheel 1. 3 and an inner ring 8 fitted on the small-diameter step portion 7.

  An inner first track 10 is provided on the outer peripheral surface of the shaft portion 3 of the hub wheel 1, an inner second track 11 is provided on the outer peripheral surface of the inner ring 8, and two rows are provided on the inner peripheral surface of the outer member 6. Tracks 12 and 13 are provided. The inner first track 10 of the hub wheel 1 and the outer first track 12 of the outer member 6 face each other, and the inner second track 11 of the inner ring 8 and the outer second track 13 of the outer member 6 face each other. The ball 5 is interposed between them. The ball 5 is held by cages (cages) 14 and 15.

  A pilot 16 is formed on the end surface of the shaft portion 3 of the hub wheel 1 (the end surface on the side opposite to the bearing structure) to which a brake rotor (not shown) is externally fitted. A mounting hole 17 is provided in the flange 4 along the circumferential direction, and a hub bolt 18 is mounted in the mounting hole 17. That is, a brake rotor or the like is superimposed on an end surface (end surface on the side opposite to the bearing structure) 19 of the flange 4 and fixed by the hub bolt 18.

  The end of the shaft 3 opposite to the flange is crimped, and the inner ring 8 is fastened to the shaft 3. Further, the outer member 6 is provided with a flange 20 having a screw hole 21 into which a vehicle body mounting bolt member (not shown) is screwed.

  By the way, a brake device includes a drum brake (a brake that generates a braking force by pressing a brake shoe with a friction material affixed to a cylindrical brake drum that rotates integrally with a wheel), a disc brake ( There are cylinder-type brake discs that rotate integrally with the wheels, and brakes that generate braking force by tightening brake pads with friction material attached from both sides, and drum-in disc brakes (drum built-in disc brakes).

In the case of a drum brake or a drum-in-disc brake, as shown in FIG. 3, these brake components 22 are arranged in the wheel bearing device. That is, the brake component 22 is disposed on the outer peripheral side of the outer member 6 between the flange 4 of the hub wheel 1 and the flange 20 of the outer member 6.
JP 2000-168306 A

  As shown in FIG. 3, when the brake component 22 is arranged on the outer peripheral side of the outer member 6, the outer diameter of the body portion 6 a of the outer member 6 is prevented so that the outer member 6 does not interfere with the brake component 22. The dimension D1 (see FIG. 4) needs to be a small diameter. However, when the outer diameter of the body portion 6a of the outer member 6 is reduced, the thickness of the body portion 6a becomes thin, the rigidity of the outer member 6 is reduced, and the outer member 6 is loaded under load. There was a problem that deformed.

  In view of the above problems, the present invention provides a wheel bearing device capable of avoiding interference with brake parts without reducing rigidity.

  A wheel bearing device according to the present invention is a wheel bearing device including a hub ring having a flange extending in an outer diameter direction and a bearing structure portion fitted on the hub wheel. A part of the outer diameter surface is provided with a notch for preventing brake component interference.

  According to the wheel bearing device of the present invention, a part of a brake component such as a drum brake can be disposed so as to correspond to the notch portion of the outer member of the bearing structure portion. For this reason, the interference of the outer member of the bearing structure portion to the brake component can be avoided, and the outer diameter of the outer member can be increased.

  The notch portion can be formed by a flat portion formed on the outer diameter surface of the outer member of the bearing structure portion, and can be formed by forging.

  Further, the notch can be formed by additional processing in the device assembly state. That is, the notch can be formed after assembly.

According to the wheel bearing device of the present invention, it is possible to avoid the interference of the brake component to the outer member of the bearing structure portion, and to increase the outer diameter of the outer member. For this reason, the thickness of the outer member can be increased, the rigidity is increased, and the deformation of the outer member due to a load can be suppressed.

  Moreover, a notch part can be comprised by the flat part formed in the outer-diameter surface of the outer member of a bearing structure part. For this reason, a notch part can be formed easily without performing a complicated process for forming a notch part. And since a notch part can be formed by a forge process, it is excellent in a moldability and can be manufactured at low cost.

  Since the notch can be formed after assembly, the positional relationship with the mating parts (part of the brake parts such as drum brakes) is strict, and if the forging process has a wide tolerance range, setting is difficult. This notch may be formed.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 and 2.

  FIG. 1 shows a wheel bearing device according to the present invention. As shown in FIG. 1, the wheel bearing device has a hub ring 31 having a flange 34 extending in the outer diameter direction, and a bearing structure fitted on the hub ring 31. Part 32. The hub wheel 31 includes a shaft portion 33 and the flange 34 protruding from the shaft portion 33.

  The bearing structure portion 32 includes a ball 35 as a rolling element, an outer member (outer ring) 36 disposed on the outer peripheral side of the shaft portion 33 of the hub wheel 31 via the ball 35, and a shaft portion of the hub wheel 31. And an inner ring 38 fitted on the 33 small-diameter stepped portion 37.

  An inner first track 40 is provided on the outer peripheral surface of the shaft portion 33 of the hub ring 31, an inner second track 41 is provided on the outer peripheral surface of the inner ring 38, and two rows are provided on the inner peripheral surface of the outer member 36. Tracks 42 and 43 are provided. The inner first track 40 of the hub wheel 31 and the outer first track 42 of the outer member 36 face each other, and the inner second track 41 of the inner ring 38 and the outer second track 43 of the outer member 36 face each other. The ball 35 is interposed between them. The ball 35 is held by cages (cages) 44 and 45.

  A pilot 46 is formed on the end surface of the shaft portion 33 of the hub wheel 31 (the end surface on the side opposite to the bearing structure). A mounting hole 47 is provided in the flange 34 along the circumferential direction, and a hub bolt 48 is mounted in the mounting hole 47. That is, a brake rotor or the like is superimposed on an end face (end face on the side opposite to the bearing structure) 49 of the flange 34 and fixed by the hub bolt 48.

  The outer member 36 includes a cylindrical body portion 52 and a flange 50 protruding from the body portion 52 in the outer diameter direction, and a vehicle body mounting bolt member (not shown) is screwed to the flange 50. A screw hole 51 is provided.

  A notch 53 is provided in a part of the outer diameter surface 52 a of the body 52 of the outer member (outer ring) 36. The notch 53 in this case is constituted by a flat portion 54 formed on the outer diameter surface 52a of the outer member 36, as shown in FIG. Moreover, the notch 53 which consists of this flat part 54 can be formed by a forge process. Forging may be free forging or die forging.

  The forged product has the following characteristics. The material can be saved, and the shape and size are close to the final shape of the product. Cutting process by machine tool can be omitted or saved. Mass-produced shapes that are difficult to cut. The structure becomes dense and there are no internal defects. Less variation in mechanical properties such as tensile strength and hardness. Metal flow (forging line) along the product shape can be obtained. There is little variation in dimensions. A forged product having such many features is a tough and highly reliable product.

  In the case of a drum brake or a drum-in-disc brake, these brake components 55 are disposed between the flange 34 of the hub wheel 31 and the flange 50 of the outer member 36 on the outer peripheral side of the outer member 36. Therefore, in this wheel bearing device, the notch 53 is made to correspond to the brake component 55.

  If such a notch 53 is not provided in the outer member 36, a part of the outer diameter surface 52a of the outer member 36 (the closest part of the brake component 55), as shown by the phantom lines in FIGS. 60 makes contact (interference) with the brake component 55. For this reason, by providing the notch 53, it is possible to avoid interference of the outer member 36 with the brake component 55 without changing the positional relationship between the brake component 55 and the wheel bearing device.

  In the wheel bearing device of the present invention, a part of a brake component such as a drum brake can be arranged corresponding to the notch 53 of the outer member 36 of the bearing structure portion 32. For this reason, interference of the outer member 36 of the bearing structure portion 32 to the brake component 55 can be avoided, and the outer diameter dimension D of the outer member 36 can be increased. For this reason, the thickness of the outer member 36 can be increased, the rigidity is increased, and deformation of the outer member 36 due to a load can be suppressed.

  Further, the notch 53 can be constituted by a flat portion 54 formed on the outer diameter surface of the outer member 36 of the bearing structure portion 32. For this reason, the notch part 53 can be easily formed without performing a complicated process for forming the notch part. And since the notch part 53 can be formed by a forge process, it is excellent in a moldability and can be manufactured at low cost. That is, the outward member 36 of the wheel bearing device can exhibit the characteristics of the forged product described above.

  The notch depth A of the notch 53 can be arbitrarily set within a range in which interference of the outer member 36 of the bearing structure part 32 with the brake component 55 can be avoided. If the notch depth A is large, interference can be reliably avoided, but the thickness T of the portion 60 corresponding to the notch 53 becomes thin and the strength is inferior. For this reason, the cutout portion 53 may have a minimum cutout depth A at which the cutout surface 53 a does not contact the brake component 55.

  By the way, when the positional relationship with a counterpart part (a part of a brake part such as a drum brake) is strict and the setting range is difficult due to a wide tolerance range in forging, this notch 53 is formed after assembly. That's fine. That is, if it is not after assembly that it is not known whether or not the outer member 36 interferes with the brake component 55, such a notch 53 may be formed after assembly. For this reason, the notch 53 may be formed not only by forging but also by cutting, before or after assembly.

  As described above, the embodiment of the present invention has been described. However, the present invention is not limited to the above-described embodiment, and various modifications are possible. For example, as a wheel bearing device, even for a driven wheel, a drive wheel May be used. In the embodiment, the rolling element is constituted by the ball 35, but a tapered roller may be used for the rolling element. Furthermore, as the wheel bearing device, in the embodiment, a raceway surface (rolling surface) is directly formed on the outer periphery of the hub wheel (referred to as a third generation), but a pair of inner rings are mounted on the hub wheel. (Press-fitted) (called 1st generation or 2nd generation), and further formed with a raceway surface (rolling surface) directly on the outer periphery of the outer joint member of the hub wheel and constant velocity universal joint ( It may be a so-called fourth generation).

  Further, the cutout portion 53 is not constituted by the flat portion 54 but can be constituted by a groove or the like slightly larger than the outer shape of the brake component 55 to be used. Further, the cutout portion 53 of the embodiment is formed from the inner diameter portion of the flange 50 (the inner diameter portion of the flange end surface on the flange 34 side of the hub wheel 31) to the end surface 61 of the body portion 52 on the flange 34 side of the hub wheel 31. However, it may be formed only on the corresponding part of the brake component 55. That is, as the notch 53, the outer member 36 does not have to interfere with the brake component 55 corresponding to the shape of the brake component 55 (there may be a non-circular cross-sectional bar shape).

It is sectional drawing of the wheel bearing apparatus of this invention. It is a simplification figure showing the relation between the wheel bearing device and brake parts. It is sectional drawing of the conventional wheel bearing apparatus. It is a simplification figure showing the relation between the above-mentioned conventional wheel bearing device and brake parts.

Explanation of symbols

31 Hub Wheel 32 Bearing Structure 34 Flange 36 Outer Member 52a Outer Diameter Surface 53 Notch 54 Flat Part

Claims (4)

In a wheel bearing device including a hub ring having a flange extending in an outer diameter direction and a bearing structure portion fitted on the hub ring,
A bearing device for a wheel, wherein a notch portion for preventing brake component interference is provided in a part of an outer diameter surface of an outer member of the bearing structure portion.   The wheel bearing device according to claim 1, wherein the notch portion is configured by a flat portion formed on an outer diameter surface of an outer member of the bearing structure portion.   The wheel bearing device according to claim 1 or 2, wherein the notch is formed by forging.   The wheel bearing device according to claim 1 or 2, wherein the notch is formed by additional processing in an assembly state of the device.

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