JP2008115984A - Bearing device for wheel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a bearing device for a wheel having improved durability. <P>SOLUTION: A grease supply hole 15 for supplying grease to a space 14 between an outer member 4 and an inner member 3, is bored in one place of a side surface of the outer member 4. The grease supply hole 15 is arranged between outside rolling surfaces 4a and 4a of a double row of the outer member 4. The grease supply hole 15 is also obliquely arranged outward in the radial direction so as to become the right-angled direction to an outer peripheral surface of a vehicle body installing flange 4b. A female screw 15a is formed on an upper side inner peripheral surface of Fig. of the grease supply hole 15. A male screw is formed in one end part in the female screw 15a, and is fitted with a grease nipple 15 forming an L shape as a whole. A cover 17 is put on an end part of the grease nipple 16 so as not to allow mud to stick to its end part. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a wheel bearing device for rotatably supporting a wheel of an automobile or the like with respect to a suspension device, and more particularly to a wheel bearing device having improved durability.

  2. Description of the Related Art Conventionally, a wheel bearing device for supporting a wheel of an automobile or the like is such that a hub wheel for mounting a wheel is rotatably supported via a rolling bearing, and there are a drive wheel and a driven wheel. For structural reasons, an inner ring rotation method is generally used for driving wheels, and an inner ring rotation method and an outer ring rotation method are generally used for driven wheels.

  As the wheel bearing device, a double-row angular ball bearing having a desired bearing rigidity, exhibiting durability against misalignment, and having a small rotational torque from the viewpoint of improving fuel efficiency is often used. On the other hand, double row tapered roller bearings are used in vehicles such as off-road cars and trucks that have a heavy vehicle body weight.

  Since these wheel bearing devices are arranged at sites where muddy water or the like is easily applied, a seal device is mounted to seal between the outer member and the inner member. Generally, in a sealing device, a sealing member having a sealing lip is attached to an outer member serving as a stationary member, and the sealing lip is slidably contacted with an outer peripheral surface of the inner member.

Then, grease is applied to the space formed between the outer member and the inner member in order to improve the durability of the bearing. Patent Document 1 shows an example in which grease is sealed in such a space. In this example, grease containing a base oil, a thickener, and inorganic bismuth is used to improve durability.
JP 2006-52751 A

  However, in such a conventional wheel bearing device, the grease may gradually flow out of the space, or the grease may deteriorate and the performance of the bearing may deteriorate. If the lubrication is not successful, metal powder or the like is generated, which may reduce the durability of the bearing.

  The present invention has been made in view of such conventional problems, and an object thereof is to provide a wheel bearing device in which the durability of the device is improved.

  In order to achieve such an object, the present invention provides an outer member having a double row outer rolling surface formed on the inner periphery and a vehicle body mounting flange formed on the outer periphery, and a wheel mounting flange on the end on the outboard side. A hub ring having a cylindrical small-diameter step portion extending in the axial direction on the outer periphery, and at least one inner ring press-fitted into the small-diameter step portion of the hub ring. A wheel bearing comprising: an inner member in which a double row inner rolling surface facing the outer rolling surface is formed; and a double row rolling element that is slidably accommodated between the both rolling surfaces. In the apparatus, a grease supply hole for supplying grease to a space between the outer member and the inner member is provided between the outer raceway surfaces of the double row on the inner periphery of the outer member. The structure provided so that the outer periphery of a direction member might be penetrated was employ | adopted.

  Thus, the grease supply hole for supplying grease to the space between the outer member and the inner member is formed between the outer rolling surfaces of the double row on the inner periphery of the outer member. It is provided so as to penetrate the outer periphery of the outer member. Therefore, the space and the outside of the bearing device can be connected relatively simply by providing the through hole in the outer member, the grease can be easily supplied, and the durability of the bearing can be improved. In addition, since the through-holes are provided between the outer rolling surfaces of the double row on the inner periphery of the outer member, the grease supplied to the space spreads to the bearing portions located on both sides of the space, which is suitable for bearing lubrication. The durability of the bearing can be improved.

  Further, the present invention has an outer member in which a double row outer rolling surface is formed on the inner periphery and a vehicle body mounting flange is formed on the outer periphery, and a wheel mounting flange is integrally formed on the end on the outboard side, A hub ring formed with a cylindrical small-diameter step portion extending in the axial direction on the outer periphery, and at least one inner ring press-fitted into the small-diameter step portion of the hub ring. In the wheel bearing device, comprising: an inner member in which opposing double-row inner rolling surfaces are formed; and a double-row rolling element that is movably accommodated between the two rolling surfaces; A grease supply hole for supplying grease to the space between the inner member and the inner member passes through the inside of the hub wheel from between the inner row rolling surfaces of the double row on the outer periphery of the inner member. So that the grease can be properly supplied and the durability of the bearing is improved. Door can be.

  Further, according to the present invention, since the grease nipple is fitted to the outer end portion of the grease supply hole, the grease can be suitably supplied.

  Further, according to the present invention, the wheel mounting flange is provided with a grease supply through-hole penetrating in the axial direction for attaching a supply means for supplying grease to the grease nipple. It can be suitably performed.

  The wheel bearing device according to the present invention has an outer member in which a double row outer rolling surface is formed on the inner periphery and a vehicle body mounting flange is formed on the outer periphery, and the wheel mounting flange is integrated with an end portion on the outboard side. A hub wheel having a cylindrical small-diameter step portion extending in the axial direction on the outer periphery, and at least one inner ring press-fitted into the small-diameter step portion of the hub wheel, and the outer periphery of the double row on the outer periphery. A wheel bearing device comprising: an inner member in which a double row inner rolling surface facing the rolling surface is formed; and a double row rolling element that is rotatably accommodated between the both rolling surfaces. And a grease supply hole for supplying grease to a space between the outer member and the inner member is formed between the outer rolling surfaces of the double row on the inner periphery of the outer member. Since it is provided so as to penetrate the outer periphery of the member, grease can be suitably supplied and the bearing resistance It is possible to improve the resistance.

  An outer member having a double row outer raceway formed on the inner periphery and a vehicle body mounting flange formed on the outer periphery, and a wheel mounting flange integrally formed on the end on the outboard side, extend in the axial direction on the outer periphery. A hub ring formed with a cylindrical small-diameter step portion and at least one inner ring press-fitted into the small-diameter step portion of the hub ring, and the inner side of the double row facing the outer rolling surface of the double row on the outer periphery A wheel bearing device comprising: an inner member having a rolling surface formed therein; and a double row rolling element that is rotatably accommodated between the both rolling surfaces, wherein the outer member and the inner member are provided. Grease supply holes for supplying grease to the space between the members are provided so as to penetrate the outer periphery of the outer member from between the outer rolling surfaces of the double row on the inner periphery of the outer member. And a grease nipple is fitted to the outer end of the grease supply hole.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a longitudinal sectional view showing a first embodiment of a wheel bearing device according to the present invention. FIG. 2 is a longitudinal sectional view showing a grease supply method. In the following description, the side closer to the outer side of the vehicle when assembled to the vehicle is referred to as the outboard side (left side in the drawing), and the side closer to the center is referred to as the inboard side (right side in the drawing).

  This wheel bearing device is a wheel bearing device that rotatably supports a drive wheel. The wheel bearing device 2 rolls between an inner member 3, an outer member 4, and both members 3, 4. Double-row rolling elements (conical rollers) 5 and 5 that are freely accommodated are provided. Here, the inner member 3 refers to the hub wheel 1 and a pair of inner rings 10 and 11 press-fitted into the hub wheel 1.

  The hub wheel 1 integrally has a wheel mounting flange 6 that extends in a disc shape on the outer periphery thereof. Hub bolt insertion holes 6 b are formed at circumferentially equidistant positions of the wheel mounting flange 6. A hub bolt 6a for fastening a wheel is implanted in the hub bolt insertion hole 6b. The wheel mounting flange 6 is provided with a grease supply through hole 6c penetrating in the axial direction, as will be described in detail later. Furthermore, the inside of the hub wheel 1 is hollow, and a torque transmission spline 1a is formed on the inner peripheral surface thereof.

  A cylindrical small-diameter stepped portion 7 extending in the axial direction is formed on the outer periphery of the wheel mounting flange 6 of the hub wheel 1 on the inboard side, and the inner rings 10 and 11 are press-fitted into the small-diameter stepped portion 7 through a predetermined shimiro. Has been. And the crimping part 8 is formed by plastically deforming the edge part of the small diameter step part 7 to radial direction outward. The inner rings 10 and 11 are fixed to the hub wheel 1 in the axial direction by the caulking portion 8 to form a so-called second generation self-retaining structure. Therefore, the rigidity of the hub wheel 1 can be increased, and the weight and size can be reduced. Moreover, since it is not necessary to control the preload amount by tightening the inner ring firmly with a nut or the like as in the prior art, it is possible to simplify the incorporation into the vehicle and maintain the preload amount for a long time. In addition, the number of parts can be greatly reduced, and in combination with the improvement of incorporation, low cost, light weight and compactness can be achieved.

  Double rows of outer rolling surfaces 4 a and 4 a are formed on the inner periphery of the outer member 4. On the other hand, an inner rolling surface of the inner member 3 is formed at a position facing these outer rolling surfaces 4a and 4a. Among them, one inner rolling surface 10 a is formed on the outer periphery of the inner ring 10, and the other inner rolling surface 11 a is formed on the outer periphery of the inner ring 11. Double-row rolling elements 5 and 5 are accommodated between the rolling surfaces 4a, 10a and 4a and 11a, and the double-row rolling elements 5 and 5 are held by a cage 9 so as to be freely rollable.

  A seal 12 a is attached to an end portion on the outboard side of the outer member 4, and the annular space between the outer member 4 and the inner member 3 is sealed. On the other hand, a seal 12b is attached to the end of the outer member 4 on the inboard side, and the annular space between the outer member 4 and the inner member 3 is sealed. These seals 12a and 12b prevent leakage of the lubricating grease sealed inside the bearing and prevent rainwater and dust from entering the bearing from the outside.

  Further, the outer member 4 integrally has a vehicle body mounting flange 4b attached to a knuckle (not shown) constituting a suspension device on the outer periphery, and a plurality of bolt insertion holes 13 are formed on the outer periphery of the vehicle body mounting flange 4b. It has been drilled. And it is fixed to the knuckle by a knuckle bolt (not shown) that penetrates the bolt insertion hole 13.

  Further, as shown in the upper part of FIG. 1, a grease supply hole 15 for supplying grease to a space 14 between the outer member 4 and the inner member 3 is provided at one place on the side surface of the outer member 4. It has been drilled. The grease supply hole 15 is provided between the double row outer rolling surfaces 4 a and 4 a of the outer member 4. Further, the grease supply hole 15 is provided obliquely outward in the radial direction so as to be perpendicular to the outer peripheral surface of the vehicle body mounting flange 4b. A female screw 15 a is formed on the inner peripheral surface of the grease supply hole 15 on the upper side in the drawing. A screw is formed at one end of the female screw 15a, and a grease nipple 16 having an L shape as a whole is fitted therein. The end of the grease nipple 16 is covered with a cover 17 so that mud or the like does not adhere to the end. As shown in FIG. 1, the grease supply hole 15 and the grease nipple 16 are disposed so as to be positioned at the upper part of the apparatus when the vehicle body mounting flange 4b is attached to the knuckle. Thereby, leakage of grease from the grease nipple 16 can be prevented.

  When supplying grease to the space 14, first, the hub wheel 1 is rotated so that the grease supply through-hole 6 c comes to a position where the grease nipple 16 exists, and the cover 17 of the grease nipple 16 is removed. Then, as shown in FIG. 2, a grease supply nozzle 18 or the like as supply means for supplying grease is attached to the grease nipple 16 from the outside through the grease supply through hole 6c. Then, grease is supplied to the space 14 and the cover 17 is put on again. The grease supply through-holes 6 c are formed at equal circumferential positions on the wheel mounting flange 6. Thereby, the influence on the rotation balance of the hub wheel 1 can be reduced.

  The hub wheel 1 is made of medium and high carbon steel containing 0.40 to 0.80 wt% of carbon such as S53C, and the surface hardness is increased by induction hardening on the inboard side base portion and the small diameter step portion 7 of the wheel mounting flange 6. It is cured in the range of 58 to 64 HRC. The caulking portion 8 is an unquenched portion having a material surface hardness of 25 HRC or less after forging. As a result, the rigidity of the hub wheel 1 is improved and fretting wear of the fitting surface with the inner rings 10 and 11 can be prevented, and the durability of the hub wheel 1 is improved. In addition, the workability when plastically deforming the caulking portion 8 is improved, and the occurrence of cracks and the like during processing is prevented, and the reliability of the quality is improved.

  Further, the outer member 4 is formed of medium and high carbon steel containing 0.40 to 0.80 wt% of carbon such as S53C, similar to the hub wheel 1, and the surface of the double row outer rolling surfaces 4a and 4a is induction hardened. Hardening is performed in the range of 58 to 64 HRC. On the other hand, the inner rings 10 and 11 are made of high carbon chrome bearing steel such as SUJ2, and are hardened in the range of 58 to 64 HRC to the core portion by quenching.

Next, a second embodiment of the wheel bearing device according to the present invention will be described.
FIG. 3 is a longitudinal sectional view showing a second embodiment of the wheel bearing device according to the present invention.

  This wheel bearing device is a wheel bearing device that rotatably supports a driven wheel. The wheel bearing device 32 rolls between an inner member 33, an outer member 34, and both members 33, 34. It is provided with double-row rolling elements (balls) 35, 35 that are freely accommodated. Here, the inner member 33 refers to the hub ring 31 and the inner ring 40 press-fitted into the hub ring 31.

  The hub wheel 31 integrally has a wheel mounting flange 36 that extends in a disc shape on the outer periphery thereof. Hub bolt insertion holes 36 b are formed in the circumferentially equidistant positions of the wheel mounting flange 36. A hub bolt 6a for fastening a wheel is implanted in the hub bolt insertion hole 36b.

  An inner rolling surface 31a and a cylindrical small-diameter step portion 37 extending in the axial direction from the inner rolling surface 31a are formed on the outer periphery of the wheel mounting flange 36 of the hub wheel 31 on the inboard side. The inner ring 40 is press-fitted through a predetermined scissors. An inner rolling surface 40 a is formed on the outer periphery of the inner ring 40. And the crimping part 38 is formed by carrying out the plastic deformation of the edge part of the small diameter step part 37 to radial direction outward. The inner ring 40 is fixed in the axial direction with respect to the hub ring 31 by the caulking portion 38 to form a so-called third generation self-retained structure.

  Further, a grease supply hole 45 for supplying grease to the space 44 between the outer member 34 and the inner member 33 is provided inside the hub wheel 31. The grease supply hole 45 is provided toward the center of the hub wheel 31 from between the double-row inner rolling surfaces 31a, 40a on the outer periphery of the inner member 33, and is perpendicular to the axially outboard side at the approximate center. It bends to the center end of the hub wheel 31 as it is. A female screw 45 a is formed at the end of the grease supply hole 45. The internal thread 45a is fitted with a grease nipple 46 having a thread formed at one end. Since the grease nipple 46 is located at the center end of the hub wheel 31, the influence on the rotation balance of the hub wheel 1 can be reduced.

  Double rows of outer rolling surfaces 34a, 34a are formed on the inner periphery of the outer member 34, and one of the inner rolling surfaces of the inner member 33 facing the outer rolling surfaces 34a, 34a is the inner side of the inner member 33. The rolling surface 31 a is formed on the hub wheel 31, and the other inner rolling surface 40 a is formed on the outer periphery of the inner ring 40. Double-row rolling elements 35, 35 are accommodated between the rolling surfaces 34a, 31a and 34a, 40a, and these double-row rolling elements 35, 35 are held by a retainer 39 so as to be freely rollable.

  A seal 42 a is attached to an end portion of the outer member 34 on the outboard side, and the annular space between the outer member 34 and the inner member 33 is sealed. On the other hand, a seal 42 b is attached to the end portion of the outer member 34 on the inboard side, and the annular space between the outer member 34 and the inner member 33 is sealed. These seals 42a and 42b prevent the lubricating grease sealed inside the bearing from leaking to the outside and preventing rainwater, dust, etc. from entering the bearing from the outside.

  Further, the outer member 34 integrally has a vehicle body mounting flange 34b attached to a knuckle (not shown) constituting the suspension device on the outer periphery, and a plurality of bolt insertion holes 43 are formed on the outer periphery of the vehicle body mounting flange 34b. It has been drilled. Then, a knuckle bolt (not shown) is screwed into the bolt insertion hole 43 and fixed to the knuckle. Furthermore, a substantially cylindrical pilot portion 34c extending toward the inboard side is formed at the base portion of the vehicle body mounting flange 34b of the outer member 34. The pilot portion 34c guides the inner diameter surface of the knuckle attached to the vehicle body mounting flange 34b.

  The embodiment of the present invention has been described above, but the present invention is not limited to such an embodiment, and is merely an example, and various modifications can be made without departing from the scope of the present invention. Of course, the scope of the present invention is indicated by the description of the scope of claims, and further, the equivalent meanings described in the scope of claims and all modifications within the scope of the scope of the present invention are included. Including.

  The wheel bearing device according to the present invention can be applied to an inner ring rotating type wheel bearing device of any structure such as a driving wheel, a driven wheel, or a rolling element having a ball, a tapered roller or the like.

It is a longitudinal section showing a 1st embodiment of a bearing device for wheels concerning the present invention. It is a longitudinal cross-sectional view which shows the grease supply method. It is a longitudinal cross-sectional view which shows 2nd Embodiment of the wheel bearing apparatus which concerns on this invention.

Explanation of symbols

1, 31 ... hub wheel 1a ... splines 10a, 11a, 31a, 40a ... inner rolling Surface 2, 32... Wheel bearing device 3, 33... Inner member 4, 34 ..... Outside members 4a, 34a ......... Outer rolling surfaces 4b, 34b ......... Car body mounting flange 5 , 35 ... Rolling element 6, 36 ... Wheel mounting flange 6a ... ...... Hub bolts 6b, 36b ... Hub bolt insertion holes 6c ... Grease supply through holes 7, 37 ... .... Small diameter step 8, 8 ···························································· 9 .... Inner rings 12a, 12b, 42a, 42b ... Seal 13, 43 ......... Bolt insertion holes 14, 44 ......... Space 15, 45 ... Grease supply holes 15a, 45a ... Female threads 16, 46 ...・ Grease nipple 17 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Cover 18 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Greasing nozzle 34c ・ ・ ・ ・ ・ ・ ・ ・・ ・ ・ ・ ・ ・ ・ Pilot part

Claims (4)

An outer member having a double row outer raceway formed on the inner periphery and a vehicle body mounting flange formed on the outer periphery;
A hub wheel integrally having a wheel mounting flange at an end portion on the outboard side and having a cylindrical small diameter step portion extending in the axial direction on the outer periphery, and at least one press-fitted into the small diameter step portion of the hub wheel An inner member formed of an inner ring, and an inner member in which a double-row inner rolling surface facing the double-row outer rolling surface is formed on the outer periphery;
In a wheel bearing device comprising: a double-row rolling element accommodated between the rolling surfaces so as to be freely rollable;
A grease supply hole for supplying grease to a space between the outer member and the inner member is formed between the outer raceway surfaces of the double row on the inner periphery of the outer member. A wheel bearing device characterized by being provided so as to penetrate the outer periphery. An outer member having a double row outer raceway formed on the inner periphery and a vehicle body mounting flange formed on the outer periphery;
A hub wheel integrally having a wheel mounting flange at an end portion on the outboard side and having a cylindrical small diameter step portion extending in the axial direction on the outer periphery, and at least one press-fitted into the small diameter step portion of the hub wheel An inner member formed of an inner ring, and an inner member in which a double-row inner rolling surface facing the double-row outer rolling surface is formed on the outer periphery;
In a wheel bearing device comprising: a double-row rolling element accommodated between the rolling surfaces so as to be freely rollable;
A grease supply hole for supplying grease to a space between the outer member and the inner member is provided between the inner raceway surfaces of the double row on the outer periphery of the inner member. A wheel bearing device characterized by being provided so as to penetrate therethrough.   The wheel bearing device according to claim 1 or 2, wherein a grease nipple is fitted to an outer end portion of the grease supply hole. 4. The wheel bearing device according to claim 1, wherein the wheel mounting flange is formed with a grease supply through hole penetrating in an axial direction for mounting grease supplying means on the grease nipple. 5.

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