JP2017154599A - Wheel bearing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wheel bearing device that is capable of improving the strength of a wheel attaching flange while suppressing the increase of overall weight to a minimum limit.SOLUTION: The wheel bearing device in which a wheel attaching flange 4b comprising a plurality of radially projected parts 4i and a plurality of hub bolts 4d pressed into the projected parts 4i is formed in the outer periphery of a hub ring 4 has reinforcing parts 4j in the front edge parts of the projected parts 4i during the main-direction rotation of an inner member, and each of the reinforcing parts 4j is formed from the base end of the projected part 4i to over the pitch circle P of the hub bolt 4d.SELECTED DRAWING: Figure 5

Description

  The present invention relates to a wheel bearing device. More specifically, the present invention relates to a wheel bearing device capable of improving the strength of a wheel mounting flange while suppressing an increase in the overall weight to a minimum.

  2. Description of the Related Art Conventionally, a wheel bearing device that rotatably supports a wheel in a suspension device such as an automobile is known. In the wheel bearing device, an outer member is fixed to a knuckle constituting the suspension device. Further, in the wheel bearing device, a double row rolling element is interposed inside the outer member, and the inner member is supported by the rolling element. In this way, the wheel bearing device constitutes a rolling bearing structure, and the wheel attached to the inner member is rotatable.

  By the way, the bearing device for wheels is comprised by the inner ring | wheel by which the inner member was fitted by the hub ring and the small diameter step part of the hub ring, and the wheel attachment flange was formed in the outer periphery of a hub ring. Moreover, the wheel mounting flange includes a plurality of projecting portions projecting radially and a plurality of hub bolts press-fitted into the projecting portions (see Patent Document 1). However, such a wheel mounting flange has a problem in that strong stress concentration occurs in a part of the protruding portion, while realizing a reduction in the overall weight. That is, there is a problem in that stress concentration occurs near the through hole through which the hub bolt is inserted, and on the front side during rotation in the main direction from the through hole. Therefore, there has been a demand for a wheel bearing device that can improve the strength of the wheel mounting flange while minimizing an increase in the overall weight.

JP 2013-91404 A

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a wheel bearing device capable of realizing an improvement in strength of a wheel mounting flange while minimizing an increase in overall weight.

  That is, the first invention is an outer member in which a double row outer rolling surface is integrally formed on the inner periphery, a hub wheel in which a small diameter step portion extending in the axial direction is formed on the outer periphery, and the hub wheel. The inner member is composed of at least one inner ring press-fitted into the small-diameter step portion, and has an inner member formed on the outer periphery with a double row inner raceway facing the double row outer raceway, A plurality of rolling elements interposed between the rolling surfaces of the inner member so as to be freely rollable, and a plurality of radially projecting protrusions, and a plurality of press-fitted into the plurality of projecting parts, respectively. In the wheel bearing device in which a wheel mounting flange including a hub bolt is formed on the outer periphery of the hub wheel, a reinforcing portion is provided at a front edge portion of the protruding portion when the inner member rotates in a main direction, and the reinforcement At least from the base end of the protrusion. Are formed to the extent of more than a circle, in which a.

  According to a second aspect of the present invention, in the wheel bearing device according to the first aspect, the reinforcing portion has a shape in which a front edge portion of the protruding portion swells to the front side when rotating in the main direction.

  According to a third aspect of the present invention, in the wheel bearing device according to the first aspect, the reinforcing portion has a shape in which a front edge portion of the protruding portion rises toward the inner side.

  4th invention is the wheel bearing apparatus which concerns on 1st invention, The said reinforcement part is a shape where the front edge part of the said protrusion part swelled to the front side at the time of main direction rotation, and rose to the inner side. It is what.

  According to a fifth invention, in the wheel bearing device according to the third or fourth invention, the reinforcing portion extends from a front edge portion to a rear edge portion of the protruding portion, and a base end portion of the protruding portion is directed to the inner side. It is supposed to be a raised shape.

  As effects of the present invention, the following effects can be obtained.

  That is, the wheel bearing device according to the first aspect of the invention has a reinforcing portion at the front edge portion of the protruding portion when the inner member rotates in the main direction. And the reinforcement part is formed to the range beyond the pitch circle of a hub bolt at least from the base end of a protrusion part. With this invention, it is possible to improve the strength of the wheel mounting flange while minimizing the increase in the overall weight.

  According to the second invention, the reinforcing portion has a shape in which the front edge portion of the protruding portion swells to the front side when the main direction rotates. With this invention, it is possible to realize an improvement in the strength of the wheel mounting flange while minimizing an increase in the overall weight while having an easily manufactured shape.

  According to the third invention, the reinforcing portion has a shape in which the front edge portion of the protruding portion is raised toward the inner side. With this invention, it is possible to realize an improvement in the strength of the wheel mounting flange while minimizing an increase in the overall weight while having an easily manufactured shape.

  According to the fourth invention, the reinforcing portion has a shape in which the front edge portion of the protruding portion swells to the front side during the main direction rotation and rises to the inner side. With this invention, it is possible to realize an improvement in the strength of the wheel mounting flange while minimizing an increase in the overall weight while having an easily manufactured shape.

  According to the fifth invention, the reinforcing portion has a shape in which the base end portion of the protruding portion rises toward the inner side from the front edge portion to the rear edge portion of the protruding portion. With this invention, it is possible to further improve the strength of the wheel mounting flange.

The perspective view which shows the whole structure of the wheel bearing apparatus. Sectional drawing which shows the whole structure of the wheel bearing apparatus. The expanded sectional view which shows the partial structure of the wheel bearing apparatus. The expanded sectional view which shows the partial structure of the wheel bearing apparatus. The side view which shows the hub ring of the wheel bearing apparatus which concerns on 1st embodiment. The side view which shows the hub ring from which the one part shape of a wheel attachment flange differs. The side view which shows the hub ring of the wheel bearing apparatus which concerns on 2nd embodiment. The side view which shows the hub ring from which the one part shape of a wheel attachment flange differs. The side view which shows the hub ring of the wheel bearing apparatus which concerns on 3rd embodiment. The side view which shows the hub ring from which the one part shape of a wheel attachment flange differs.

  Below, the wheel bearing apparatus 1 which concerns on this invention is demonstrated using FIGS. 1-4. 2 is a cross-sectional view taken along the line AA in FIG. 3 and 4 are enlarged views of a partial region in FIG.

  The wheel bearing device 1 supports a wheel rotatably in a suspension device such as an automobile. The wheel bearing device 1 includes an outer member 2, an inner member 3 (hub wheel 4 and inner ring 5), a rolling element 6, a seal member 7 (hereinafter referred to as “one-side seal member 7”), and a seal member 10 (hereinafter “ (Referred to as “other-side seal member 10”). In the following, “one side” represents the vehicle body side of the wheel bearing device 1, that is, the inner side. The “other side” represents the wheel side of the wheel bearing device 1, that is, the outer side.

  The outer member 2 supports the inner member 3 (hub wheel 4 and inner ring 5). The outer member 2 is made of a medium-high carbon steel containing 0.40 to 0.80 wt% of carbon such as S53C formed in a substantially cylindrical shape. An enlarged diameter portion 2 a is formed at one end of the outer member 2. An enlarged diameter portion 2 b is formed at the other end of the outer member 2. On the inner periphery of the outer member 2, an outer rolling surface 2c and an outer rolling surface 2d are formed in an annular shape so as to be parallel to each other. The outer rolling surface 2c and the outer rolling surface 2d are subjected to induction hardening, and are hardened so that the surface hardness is in the range of 58 to 64 HRC. It should be noted that a knuckle attachment flange 2e for being attached to a knuckle constituting the suspension device is integrally formed on the outer periphery of the outer member 2.

  The inward member 3 rotatably supports a wheel (not shown). The inner member 3 includes a hub ring 4 and an inner ring 5.

  The hub wheel 4 is made of medium-high carbon steel containing carbon of 0.40 to 0.80 wt% such as S53C formed in a substantially cylindrical shape. A small diameter step 4 a is formed at one end of the hub wheel 4. An inner ring 5 is press-fitted into the small diameter step 4a. Further, the hub ring 4 is crimped to the inner ring 5 by bending its inner side end portion radially outward. A wheel mounting flange 4 b is integrally formed on the outer periphery of the hub wheel 4. The wheel mounting flange 4b is provided with a through hole 4c on a concentric circle centered on the rotation axis L of the inner member 3, and a hub bolt 4d is inserted into each through hole 4c. Further, on the outer periphery of the hub wheel 4, an annular inner rolling surface 4 e is formed in an annular shape. The hub wheel 4 is induction-hardened from the small-diameter step portion 4a to the inner rolling surface 4e, and is hardened so that the surface hardness is in the range of 58 to 64 HRC. Thereby, the hub wheel 4 has sufficient mechanical strength and durability against the rotational bending load applied to the wheel mounting flange 4b. The inner rolling surface 4e faces the outer rolling surface 2d of the outer member 2.

The inner ring 5 is made of a high carbon chrome bearing steel such as SUJ2 formed in a substantially cylindrical shape.
On the outer periphery of the inner ring 5, an inner rolling surface 5a is formed in an annular shape. That is, the inner ring 5 is fitted into the small-diameter step portion 4a of the hub wheel 4, and the inner raceway surface 5a is configured on the outer periphery of the small-diameter step portion 4a. The inner ring 5 is subjected to so-called quenching and is cured so as to be in the range of 58 to 64 HRC up to the core. Thereby, the inner ring 5 has sufficient mechanical strength and durability against the rotational bending load applied to the wheel mounting flange 4b. The inner rolling surface 5 a faces the outer rolling surface 2 c of the outer member 2.

  The rolling element 6 is interposed between the outer member 2 and the inner member 3 (hub wheel 4 and inner ring 5). The rolling element 6 has an inner side ball row 6a (hereinafter referred to as “one side ball row 6a”) and an outer side ball row 6b (hereinafter referred to as “other side ball row 6b”). The one side ball row 6a and the other side ball row 6b are made of high carbon chrome bearing steel such as SUJ2. The one-side ball row 6a and the other-side ball row 6b are subjected to so-called quenching and are cured so as to be in the range of 58 to 64 HRC up to the core portion. In the one-side ball row 6a, a plurality of balls are held in a ring shape by a cage. The one-side ball row 6a is accommodated so as to be freely rollable between an inner rolling surface 5a formed on the inner ring 5 and an outer rolling surface 2c of the outer member 2 facing the inner rolling surface 5a. In the other side ball row 6b, a plurality of balls are held in a ring shape by a cage. The other-side ball row 6b is accommodated so as to be freely rollable between an inner rolling surface 4e formed on the hub wheel 4 and an outer rolling surface 2d of the outer member 2 facing the inner rolling surface 4e. In this way, the one-side ball row 6a and the other-side ball row 6b constitute a double-row angular ball bearing with the outer member 2 and the inner member 3 (hub wheel 4 and inner ring 5). The wheel bearing device 1 is a third-generation wheel bearing device in which the inner raceway surface 4e of the other side ball row 6b is directly formed on the outer periphery of the hub wheel 4, but is not limited thereto. The second generation structure in which the pair of inner rings 5 are press-fitted and fixed to the hub ring 4 or the first ring constituted by the outer ring that is the outer member 2 without the hub ring 4 and the inner ring 5 that is the inner member. It may be a generation structure.

  The one-side seal member 7 is attached to the inner side end portion of the annular space S formed between the outer member 2 and the inner member 3. The one-side seal member 7 includes an annular seal ring 8 and an annular slinger 9.

  The seal ring 8 is configured to be integrated with the outer member 2 by being fitted into the enlarged diameter portion 2 a of the outer member 2. The seal ring 8 includes a cored bar 81 and a seal rubber 82 that is an elastic member.

  The cored bar 81 is a ferritic stainless steel plate (JIS standard SUS430 or the like), an austenitic stainless steel plate (JIS standard SUS304 or the like), or a rust-proof cold rolled steel plate (JIS standard SPCC system or the like). It consists of The cored bar 81 is formed by bending an annular steel plate by press work and has an axial cross section that is substantially L-shaped. Thereby, the cored bar 81 is formed with a cylindrical fitting part 81a and a disk-like side plate part 81b extending from one end thereof toward the inner member 3 (inner ring 5). The fitting portion 81a and the side plate portion 81b intersect each other substantially perpendicularly, and the fitting portion 81a faces a fitting portion 9a of a slinger 9 described later. Further, the side plate portion 81b faces a side plate portion 9b of the slinger 9 described later. A seal rubber 82, which is an elastic member, is vulcanized and bonded to the fitting portion 81a and the side plate portion 81b.

  Seal rubber 82 is NBR (acrylonitrile-butadiene rubber), HNBR (hydrogenated acrylonitrile-butadiene rubber) excellent in heat resistance, EPDM (ethylene propylene rubber), ACM (polyacrylic rubber) excellent in heat resistance and chemical resistance, It is made of synthetic rubber such as FKM (fluoro rubber) or silicon rubber. The seal rubber 82 is formed with a radial lip 82a, an inner axial lip 82b, and an outer axial lip 82c which are seal lips.

  The slinger 9 is fitted to the outer periphery of the inner member 3 (the outer periphery of the inner ring 5) and is configured integrally with the inner member 3.

  Slinger 9 is a ferritic stainless steel sheet (JIS standard SUS430 series, etc.), austenitic stainless steel sheet (JIS standard SUS304 series, etc.), or a rust-proof cold rolled steel sheet (JIS standard SPCC system, etc.). It is configured. The slinger 9 is formed by bending an annular steel plate by press working and has an axial cross section formed in a substantially L shape. Thereby, the slinger 9 is formed with a cylindrical fitting portion 9a and a disc-shaped side plate portion 9b extending from the end portion toward the outer member 2. The fitting portion 9a and the side plate portion 9b intersect each other vertically, and the fitting portion 9a faces the fitting portion 81a of the seal ring 8 described above. Further, the side plate portion 9b faces the side plate portion 81b of the seal ring 8 described above. The side plate portion 9b is provided with a magnetic encoder 9c.

  The one-side seal member 7 is disposed so that the seal ring 8 and the slinger 9 face each other. At this time, the radial lip 82a contacts the fitting portion 9a of the slinger 9 through the oil film. Further, the axial lip 82b contacts the side plate portion 9b of the slinger 9 through the oil film. The outer axial lip 82c also contacts the side plate portion 9b of the slinger 9 through the oil film. In this way, the one-side seal member 7 constitutes a so-called pack seal, and prevents entry of dust and the like and leakage of grease.

  The other side sealing member 10 is attached to the outer side end portion of the annular space S formed between the outer member 2 and the inner member 3. The other-side seal member 10 includes an annular seal ring 11.

  The other-side seal member 10 is configured to be integrated with the outer member 2 by being fitted into the enlarged diameter portion 2 b of the outer member 2. The seal ring 11 includes a metal core 111 and a seal rubber 112 that is an elastic member.

  The core metal 111 is a ferritic stainless steel plate (JIS standard SUS430 series, etc.), an austenitic stainless steel sheet (JIS standard SUS304 series, etc.), or a rust-proof cold rolled steel plate (JIS standard SPCC system, etc.). It consists of The core metal 111 is formed in a substantially C shape in an axial sectional view by bending an annular steel plate by press working. Thereby, the metal core 111 is formed with a cylindrical fitting portion 111a and a disk-shaped side plate portion 111b extending from one end thereof toward the inner member 3 (hub wheel 4). The fitting part 111 a and the side plate part 111 b intersect with each other while being curved, and the fitting part 111 a faces the shaft surface part 4 f of the hub wheel 4. The side plate portion 111b faces the curved surface portion 4g and the side surface portion 4h of the hub wheel 4 (refers to the end surface of the wheel mounting flange 4b). A seal rubber 112 that is an elastic member is vulcanized and bonded to the side plate portion 111b.

  Seal rubber 112 is NBR (acrylonitrile-butadiene rubber), HNBR (hydrogenated acrylonitrile-butadiene rubber) excellent in heat resistance, EPDM (ethylene propylene rubber), ACM (polyacrylic rubber) excellent in heat resistance and chemical resistance, It is made of synthetic rubber such as FKM (fluoro rubber) or silicon rubber. The seal rubber 112 is formed with a radial lip 112a, an inner axial lip 112b, and an outer axial lip 112c which are seal lips.

  The other-side seal member 10 is disposed so that the seal ring 11 and the hub wheel 4 face each other. At this time, the radial lip 112a contacts the shaft surface portion 4f of the hub wheel 4 through the oil film. Further, the axial lip 112b contacts the curved surface portion 4g of the hub wheel 4 through the oil film. The outer axial lip 112c also contacts the side surface portion 4h of the hub wheel 4 through the oil film. In this way, the other side sealing member 10 prevents intrusion of dust and the like and leakage of grease.

  Next, the wheel bearing device 1 according to the first embodiment will be described in detail with reference to FIG. FIG. 5 shows the hub wheel 4 of the wheel bearing device 1 according to the first embodiment. FIG. 5A is a view seen from the direction of the arrow B in FIG. 2, and the arrow R represents the rotation direction when the main direction is rotated. 5B is a cross-sectional view taken along the line CC in FIG.

  As described above, the wheel mounting flange 4 b is integrally formed on the outer periphery of the hub wheel 4. The wheel mounting flange 4b is composed of a plurality of projecting portions 4i projecting radially and a plurality of hub bolts 4d press-fitted into the plurality of projecting portions 4i. More specifically, a total of four projecting portions 4i projecting at a phase angle of 90 ° with the rotation axis L as the center, and a total of four projectingly inserted into the through holes 4c of the four projecting portions 4i. Hub bolt 4d. Moreover, the wheel bearing device 1 which is 1st embodiment has the reinforcement part 4j in the front-edge part of the protrusion part 4i at the time of the main direction rotation of the inner member 3. As shown in FIG. And the reinforcement part 4j is formed to the range beyond the pitch circle P of the hub volt | bolt 4d from the base end of the protrusion part 4i. That is, the reinforcing portion 4j is formed so as to cover the point E where the pitch circle P intersects the front edge portion of the conventional protruding portion 4i that does not have the reinforcing portion 4j. Here, the pitch circle P indicates a virtual circle connecting the centers of the hub bolts 4d.

  As described above, the wheel bearing device 1 according to the present invention has the reinforcing portion 4j at the front edge portion of the protruding portion 4i when the inner member 3 rotates in the main direction. And the reinforcement part 4j is formed to the range beyond the pitch circle P of the hub volt | bolt 4d from the base end of the protrusion part 4i. With this invention, it is possible to improve the strength of the wheel mounting flange 4b while minimizing an increase in the overall weight.

  Furthermore, in the wheel bearing device 1 according to the first embodiment, the reinforcing portion 4j has a shape in which the front edge portion of the protruding portion 4i swells to the front side when rotating in the main direction. That is, the wheel bearing device 1 is characterized in that a protruding portion having a length X, a width Y, and a height Z is provided at the front edge portion of the protruding portion 4i. According to this invention, the strength of the wheel mounting flange 4b can be improved while minimizing the increase in the overall weight while being easily manufactured.

  In addition, as shown in FIG. 6, the reinforcing portion 4j may be extended to the tip of the protruding portion 4i to cover the entire front edge portion. Even in this case, the same effect can be obtained. That is, the strength of the wheel mounting flange 4b can be improved while minimizing the increase in the overall weight while being in an easily manufactured shape.

  Next, the wheel bearing device 1 according to the second embodiment will be described in detail with reference to FIG. FIG. 7 shows the hub wheel 4 of the wheel bearing device 1 according to the second embodiment. FIG. 7A is a view seen from the direction of the arrow B in FIG. 2, and the arrow R represents the rotation direction when the main direction is rotated. Moreover, (B) of FIG. 7 is CC sectional drawing in (A).

  As described above, the wheel mounting flange 4 b is integrally formed on the outer periphery of the hub wheel 4. The wheel mounting flange 4b is composed of a plurality of projecting portions 4i projecting radially and a plurality of hub bolts 4d press-fitted into the plurality of projecting portions 4i. More specifically, a total of four projecting portions 4i projecting at a phase angle of 90 ° with the rotation axis L as the center, and a total of four projectingly inserted into each through hole 4c of the four projecting portions 4i Hub bolt 4d. Moreover, also in the wheel bearing apparatus 1 which is 2nd embodiment, it has the reinforcement part 4j in the front-edge part of the protrusion part 4i at the time of the main direction rotation of the inner member 3. As shown in FIG. And the reinforcement part 4j is formed to the range beyond the pitch circle P of the hub volt | bolt 4d from the base end of the protrusion part 4i. That is, the reinforcing portion 4j is formed so as to cover the point E where the pitch circle P intersects the front edge portion of the conventional protruding portion 4i that does not have the reinforcing portion 4j. Here, the pitch circle P indicates a virtual circle connecting the centers of the hub bolts 4d.

  As described above, the wheel bearing device 1 according to the present invention has the reinforcing portion 4j at the front edge portion of the protruding portion 4i when the inner member 3 rotates in the main direction. And the reinforcement part 4j is formed to the range beyond the pitch circle P of the hub volt | bolt 4d from the base end of the protrusion part 4i. With this invention, it is possible to improve the strength of the wheel mounting flange 4b while minimizing an increase in the overall weight.

  Furthermore, in the wheel bearing apparatus 1 which is 2nd embodiment, the reinforcement part 4j is a shape where the front edge part of the protrusion part 4i rose to the inner side. That is, the wheel bearing device 1 is characterized in that a protruding portion having a length X, a width Y, and a height Z is provided at the front edge portion of the protruding portion 4i. According to this invention, the strength of the wheel mounting flange 4b can be improved while minimizing the increase in the overall weight while being easily manufactured.

  In addition, as shown in FIG. 8, the reinforcing portion 4j may be extended to the tip of the protruding portion 4i to cover the entire front edge portion. Even in this case, the same effect can be obtained. That is, the strength of the wheel mounting flange 4b can be improved while minimizing the increase in the overall weight while being in an easily manufactured shape.

  In addition, the reinforcing portion 4j may have a shape in which the base end portion of the protruding portion 4i is raised to the inner side from the front edge portion to the rear edge portion of the protruding portion 4i (see the two-dot chain line F in FIG. 8). ). In this case, the strength of the wheel mounting flange 4b can be further improved.

  Next, the wheel bearing device 1 according to the third embodiment will be described in detail with reference to FIG. FIG. 9 shows the hub wheel 4 of the wheel bearing device 1 according to the third embodiment. FIG. 9A is a view seen from the direction of the arrow B in FIG. 2, and the arrow R represents the rotation direction when the main direction is rotated. Moreover, (B) of FIG. 9 is CC sectional drawing in (A).

  As described above, the wheel mounting flange 4 b is integrally formed on the outer periphery of the hub wheel 4. The wheel mounting flange 4b is composed of a plurality of projecting portions 4i projecting radially and a plurality of hub bolts 4d press-fitted into the plurality of projecting portions 4i. More specifically, a total of four projecting portions 4i projecting at a phase angle of 90 ° with the rotation axis L as the center, and a total of four projectingly inserted into the through holes 4c of the four projecting portions 4i. Hub bolt 4d. Moreover, also in the wheel bearing apparatus 1 which is 3rd embodiment, it has the reinforcement part 4j in the front-edge part of the protrusion part 4i at the time of the main direction rotation of the inner member 3. As shown in FIG. And the reinforcement part 4j is formed to the range beyond the pitch circle P of the hub volt | bolt 4d from the base end of the protrusion part 4i. That is, the reinforcing portion 4j is formed so as to cover the point E where the pitch circle P intersects the front edge portion of the conventional protruding portion 4i that does not have the reinforcing portion 4j. Here, the pitch circle P indicates a virtual circle connecting the centers of the hub bolts 4d.

  As described above, the wheel bearing device 1 according to the present invention has the reinforcing portion 4j at the front edge portion of the protruding portion 4i when the inner member 3 rotates in the main direction. And the reinforcement part 4j is formed to the range beyond the pitch circle P of the hub volt | bolt 4d from the base end of the protrusion part 4i. With this invention, it is possible to improve the strength of the wheel mounting flange 4b while minimizing an increase in the overall weight.

  Further, in the wheel bearing device 1 according to the third embodiment, the reinforcing portion 4j has a shape in which the front edge portion of the projecting portion 4i swells to the front side when the main direction rotates and rises to the inner side. That is, the wheel bearing device 1 is characterized in that a protruding portion having a length X, a width Y, and a height Z is provided at the front edge portion of the protruding portion 4i. According to this invention, the strength of the wheel mounting flange 4b can be improved while minimizing the increase in the overall weight while being easily manufactured.

  In addition, as shown in FIG. 10, the reinforcing portion 4j may be extended to the tip of the protruding portion 4i so as to cover the entire front edge portion. Even in this case, the same effect can be obtained. That is, the strength of the wheel mounting flange 4b can be improved while minimizing the increase in the overall weight while being in an easily manufactured shape.

  In addition, the reinforcing portion 4j may have a shape in which the base end portion of the protruding portion 4i rises to the inner side from the front edge portion to the rear edge portion of the protruding portion 4i (see the two-dot chain line F in FIG. 10). ). In this case, the strength of the wheel mounting flange 4b can be further improved.

DESCRIPTION OF SYMBOLS 1 Wheel bearing apparatus 2 Outer member 2c Outer rolling surface 2d Outer rolling surface 3 Inner member 4 Hub wheel 4a Small diameter step part 4b Wheel attachment flange 4c Through-hole 4d Hub bolt 4e Inner rolling surface 4i Projection part 4j Reinforcement part 5 Inner ring 5a Inner rolling surface 6 Rolling element P Pitch circle R Rotation direction during main direction rotation

Claims (5)

An outer member in which a double row outer rolling surface is integrally formed on the inner periphery;
A hub wheel having a 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 a plurality of outer rings facing the double-row outer rolling surface on the outer periphery. An inner member in which the inner rolling surface of the row is formed;
A double-row rolling element interposed between the rolling surfaces of the outer member and the inner member so as to be freely rollable, and
In the wheel bearing device in which a plurality of projecting portions projecting radially and a wheel mounting flange formed of a plurality of hub bolts press-fitted into the plurality of projecting portions are formed on the outer periphery of the hub wheel,
A reinforcing portion at the front edge portion of the protruding portion when the inner member rotates in the main direction;
The wheel bearing device according to claim 1, wherein the reinforcing portion is formed from a base end of the protruding portion to a range exceeding at least a pitch circle of the hub bolt.   2. The wheel bearing device according to claim 1, wherein the reinforcing portion has a shape in which a front edge portion of the protruding portion swells to the front side when rotating in the main direction.   2. The wheel bearing device according to claim 1, wherein the reinforcing portion has a shape in which a front edge portion of the protruding portion is raised toward the inner side.   2. The wheel bearing device according to claim 1, wherein the reinforcing portion has a shape in which a front edge portion of the protruding portion swells to the front side when the main direction rotates and rises to the inner side.   The said reinforcement part is a shape where the base end part of this protrusion part rose to the inner side from the front edge part of the said protrusion part to the rear edge part, The Claim 3 or Claim 4 characterized by the above-mentioned. Wheel bearing device.

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