JP2010195202A - Bearing ring member of hub unit for supporting wheel, and method of manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a bearing ring member of a hub unit for supporting a wheel and a method of manufacturing the same capable of reducing projection height of a head part of a bolt relative to a mounting flange while maintaining strength of the mounting flange, designing a periphery of the hub unit for supporting the wheel to a compact size and attaining light weight of a vehicle body. <P>SOLUTION: The bearing ring member of the hub unit for supporting the wheel includes: a shaft part 32; and the mounting flanges 33 extending to an outer side in a radial direction from the shaft part 32 and mounted to the wheel or the vehicle body. The mounting flange 33 is integrally molded with the shaft part 32 by side extrusion at cold, and a groove-like recessed part 37 is formed on a surface 36 at an opposite side to a mounting surface 35 of the mounting flange 33 to the wheel or the vehicle body along a radial direction. A flat surface part 37a of the groove-like recession part 37 is a bolt seat surface of a mounting bolt 13 for mounting the mounting flange 33 to the wheel or the vehicle body. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  More particularly, the present invention relates to a raceway member of a wheel support hub unit and a method of manufacturing the same, and more particularly, for example, a raceway of a wheel support hub unit for rotatably supporting a wheel of an automobile or the like with respect to a suspension device. The present invention relates to a member and a manufacturing method thereof.

  As shown in FIG. 7, a conventional bearing member for a wheel support hub unit and a method for manufacturing the same are shown. As shown in FIG. 7, a mounting flange 3 extending radially outward from the shaft portion 2 is extruded by cold side extrusion. It is known that the ring member 1 having sufficient strength can be molded at a relatively low load and at low cost by being molded integrally with No. 2 (see, for example, Patent Document 1).

JP 2006-111070 A

  In the raceway ring member 1 described in Patent Document 1, a mounting flange 3 having a substantially rectangular cross section extends radially outward from the outer peripheral surface of the shaft portion 2. By the way, a compact design is also required for the structure around the wheel supporting hub unit for the purpose of reducing the weight of the vehicle.

  Therefore, by reducing the protruding height of the head of the bolt that fixes the mounting flange 3 of the bearing ring member 1 to the wheel and the brake rotor, the interference with peripheral parts is reduced accordingly, and the wheel supporting hub unit It is considered to design the surroundings in a compact manner. However, by reducing the plate thickness of the mounting flange 3 having a substantially rectangular cross section, the strength of the mounting flange 3 may be reduced when attempting to reduce the protruding height of the bolt head.

  The present invention has been made in view of the above-described circumstances, and an object of the present invention is to reduce the height of the protrusion of the bolt head with respect to the mounting flange while maintaining the strength of the mounting flange. An object of the present invention is to provide a wheel member for a wheel supporting hub unit that can be designed compactly around the hub unit and can reduce the weight of the vehicle body, and a method for manufacturing the same.

The above object of the present invention can be achieved by the following constitution.
(1) It has a solid or hollow shaft portion, and a mounting flange that extends radially outward from the shaft portion and is attached to a wheel or a vehicle body. A ring member of a hub unit bearing that is integrally formed with a grooved recess formed along the radial direction on the surface of the mounting flange opposite to the wheel or vehicle body mounting surface. The portion is a bolt seat surface of a mounting bolt for mounting the mounting flange to a wheel or a vehicle body.
(2) A method for manufacturing a race member of a wheel support hub unit having a solid or hollow shaft portion and a mounting flange extending radially outward from the shaft portion, , A gold having a shaft molding cavity for molding the shaft, and a flange molding cavity extending radially outward from the shaft molding cavity to mold the mounting flange The process of placing in the mold, and crushing one or both ends of the material at room temperature, and flowing the material into the mold molding cavity and the flange molding cavity, radially on one axial surface of the mold And a step of forming a mounting flange, along which a groove-like recess is formed, by side-extrusion integrally with the shaft portion, and a method for manufacturing a bearing member of a wheel support hub unit.
(3) A predetermined position of the mounting flange is pressed by a mold having a flat portion having a width larger than the diameter of the head of the mounting bolt for mounting the mounting flange on the wheel or the vehicle body, and the bolt seat surface of the mounting bolt is The method of manufacturing a race member for a wheel-supporting hub unit according to (2), further comprising a forming step.

  According to the track ring member of the wheel supporting hub unit of the present invention, the groove-shaped recess along the radial direction is formed on the surface of the mounting flange extending radially outward from the shaft portion on the side opposite to the wheel or vehicle body mounting surface. And the flat portion of the groove-shaped recess is the bolt seat surface of the mounting bolt for attaching the mounting flange to the wheel or the vehicle body. Therefore, the projecting height of the bolt head relative to the mounting flange can be reduced while maintaining the strength of the mounting flange. Thereby, since the periphery of the wheel supporting hub unit can be designed compactly, the weight of the vehicle body can be reduced.

  Further, according to the method of manufacturing the bearing ring member of the wheel supporting hub unit of the present invention, the material of the bearing ring member is formed in the radial direction from the shaft part forming cavity for forming the shaft part, and the shaft part forming cavity. A step of placing in a mold having a flange forming cavity for radially extending outward and forming a mounting flange, and crushing one or both ends of the material at room temperature, A mounting flange in which a groove-shaped recess is formed along the radial direction on one surface in the axial direction by flowing into the mold molding cavity and flange molding cavity is molded by side extrusion integrally with the shaft section. The bearing ring member can be formed with high accuracy. Thereby, since the machining allowance in the machining after forging can be reduced, a bearing ring member having a good material yield can be formed with a relatively low load.

It is sectional drawing for demonstrating the hub unit for wheel support by which the track ring member which concerns on this invention was employ | adopted. It is a figure which shows the bearing ring member which concerns on this invention, (a) is a top view, (b) is a side view. It is explanatory drawing of the manufacturing process of the bearing ring member which concerns on this invention. It is sectional drawing for demonstrating the forge processing apparatus for manufacturing the bearing ring member which concerns on this invention. It is a top view of the bearing ring member before the bolt seat surface is formed in a mounting flange, showing the modification of the bearing ring member concerning the present invention. It is a top view of the bearing ring member after the modification of the bearing ring member which concerns on this invention is shown, and the bolt seat surface is formed in the attachment flange. It is a figure which shows the conventional bearing ring member, (a) is a top view, (b) is a side view.

  Hereinafter, an embodiment of a raceway member of a hub unit for supporting a wheel according to the present invention and a manufacturing method for the same will be described in detail with reference to the drawings.

  As shown in FIG. 1, the wheel support hub unit 10 of the present embodiment is a wheel support hub unit for a driven wheel, and is an outer ring member (track ring member) 20 fixed to the vehicle body side of a vehicle (not shown). And an inner ring member (orbital ring member) 30 that is connected to a wheel side of a vehicle (not shown) and rotates together with the wheel.

  Two rows of outer ring raceway grooves 21 are formed on the inner peripheral surface of the outer ring member 20, and two rows of inner ring raceway grooves 31 are formed on the outer peripheral surface of the inner ring member 30 so as to face the outer ring raceway groove 21. Between the outer ring raceway groove 21 and the inner ring raceway groove 31, a plurality of balls 11 as rolling elements are arranged to freely roll. The plurality of balls 11 are held by the cage 12 at substantially equal intervals.

  As shown in FIG. 1, the outer ring member 20 includes a hollow shaft portion 22 and a plurality of mounting flanges that are formed on the outer peripheral surface of the shaft portion 22 at predetermined intervals in the circumferential direction and extend radially outward. 23. The mounting flange 23 is formed with a bolt insertion hole 23a for inserting a not-shown bolt. The outer ring member 20 is fixed to the vehicle body side by fastening a bolt (not shown) inserted through the bolt insertion hole 23a of the mounting flange 23 to a suspension device (not shown).

  As shown in FIGS. 1 and 2, the inner ring member 30 is formed on the outer peripheral surface of the solid shaft portion 32 and one axial end portion of the shaft portion 32 at intervals of 90 ° in the circumferential direction, and radially outward. And four mounting flanges 33 extending. The mounting flange 33 is formed with a bolt fixing hole 33a for fixing the stud bolt 13 which is a mounting bolt. Further, an inner ring 34 having one row of inner ring raceway grooves 31 on the outer peripheral surface thereof is fitted and fixed to the other axial end portion of the shaft portion 32. The inner ring member 30 is fixed to the wheel side by fastening the stud bolt 13 of the mounting flange 33 to a wheel and a brake rotor (not shown).

  And in this embodiment, as shown in FIG. 2, the groove-shaped recessed part is formed along the radial direction at the circumferential center of the opposite mounting surface 36 opposite to the mounting surface 35 of the mounting flange 33 of the inner ring member 30 on the wheel. 37 is formed. That is, the mounting flange 33 has thick portions 38 on both sides in the circumferential direction of the flat portion 37a of the groove-shaped recess 37, and is formed in a substantially concave shape in section such that only a portion corresponding to the bolt seat surface of the stud bolt 13 is recessed. Is done. The flat portion 37a is formed to have a width W1 that is slightly larger than the diameter D1 of the head 13a of the stud bolt 13, and constitutes a bolt seat surface of the stud bolt 13.

  Next, with reference to FIG.3 and FIG.4, the manufacturing method of the bearing ring member of this embodiment is demonstrated. In the present embodiment, the case where the inner ring member 30 that is the race ring member shown in FIG. 2 is manufactured by cold forging will be described as an example.

  In the manufacturing method according to the present embodiment, first, as shown in FIGS. 3A to 3C, a solid cylindrical material 40 is subjected to two-stage plastic processing using a rough forming apparatus (not shown). Thus, the first intermediate material 41 and the second intermediate material 42 are formed. Next, as shown in (c) → (d) of FIG. 3, the second intermediate material 42 is subjected to side extrusion with the forging device 50 shown in FIG. The integrally molded third intermediate material 43 is formed. Next, as shown in (d) → (e) of FIG. 3, the third intermediate material 43 is subjected to pressing (sizing) with a finishing molding device (not shown), whereby the bolts of the stud bolts 13 are attached to the mounting flange 33. The final intermediate material 44 on which the seating surface 39 is formed is molded. The inner ring member 30 of the present embodiment is obtained by subjecting the final intermediate material 44 to machining such as predetermined cutting and grinding. In addition, the process of (d)-> (e) of the said FIG. 3 is a process performed when accuracy is required for a bolt seat surface, Comprising: You may abbreviate | omit when accuracy is not required for a bolt seat surface. In the present embodiment, the second intermediate material 42 corresponds to the material of the present invention.

  As shown in FIG. 4, the forging device 50 is slidably fitted into a lower mold 51 that is a fixed mold, an upper mold 52 that is a movable mold, and a hole 52 a provided in the upper mold 52. A ring punch 53 and a press punch 54 to be combined, an extrusion punch 55 slidably fitted in a hole 51 a provided in the lower mold 51, a lower surface of a mounting plate 56 of the press punch 54, and an upper mold 52. And an elastic member 57 disposed between the upper surface and the upper surface. A shaft portion forming cavity 58 for forming the shaft portion 32 and the mounting flange 33 are formed by the lower die 51, the upper die 52, the ring punch 53, the pressing punch 54, and the extrusion punch 55, which are dies. A flange forming cavity 59 for forming is defined. The flange forming cavity 59 extends radially outward from the shaft portion forming cavity 58 in the radial direction. In order to balance the material flow in the flange forming cavity 59, the lower mold 51 may be moved up and down in the same manner as the upper mold 52, and may be biased toward the upper mold 52 by an elastic member. (Upper and lower molds floating structure).

  In the side extrusion molding by the forging device 50 described above, the second intermediate material 42 of FIG. 3C is disposed in the shaft portion forming cavity 58 of the forging device 50, and then the lower die 51 and the upper die. In a state where the mold 52 is closed, the second intermediate material 42 is crushed from the upper side by the ring punch 53 and the press punch 54 from the upper side with the ring punch 53 and the press punch 54, so that the second intermediate material 42 is formed into the shaft forming cavity 58 and the flange forming. Flow into cavity 59. That is, the second intermediate material 42 is filled into the shaft portion forming cavity 58 and a part thereof is extruded from the shaft portion forming cavity 58 to the flange forming cavity 59. As a result, the mounting flange 33 in which the groove-shaped recess 37 is formed on the non-mounting surface 36 is formed integrally with the shaft portion 32.

  As described above, according to the inner ring member 30 that is the race ring member of the present embodiment, the anti-mounting surface 36 opposite to the mounting surface 35 of the mounting flange 33 that extends radially outward from the shaft portion 32 to the wheel. In addition, a groove-shaped recess 37 is formed along the radial direction, and the flat portion 37a of the groove-shaped recess 37 is a bolt seat surface of the stud bolt 13 for mounting the mounting flange 33 on the wheel side. While the thickness of the bolt seating surface can be reduced, the thickness of the peripheral portion can be increased, so that the strength of the mounting flange 33 is maintained and the head 13a of the stud bolt 13 protrudes from the mounting flange 33. The height can be reduced. Thereby, since the periphery of the wheel supporting hub unit 10 can be designed compactly, the weight of the vehicle body can be reduced.

  Further, according to the method of manufacturing the inner ring member 30 that is the race ring member of the present embodiment, the second intermediate material 42 is formed from the shaft portion forming cavity 58 for forming the shaft portion 32 and the shaft portion forming cavity 58. A radially extending outward from the flange, and a flange-forming cavity 59 for forming the mounting flange 33, and a step of disposing the upper end of the second intermediate material 42 in the axial direction. By crushing at normal temperature and allowing the second intermediate material 42 to flow into the mold-forming cavity 58 and the flange-forming cavity 59, the groove-shaped recess 37 is formed along the radial direction on the anti-attachment surface 36. And the step of forming the mounting flange 33 integrally with the shaft portion 32 by side extrusion, the inner ring member 30 can be formed with high accuracy. Thereby, since the machining allowance in the machining after forging can be reduced, the inner ring member 30 having a good material yield can be formed with a relatively low load.

  As a modification of the present embodiment, as shown in FIGS. 5 and 6, in order to increase the strength of the mounting flange 33, the width W <b> 1 of the flat portion 37 a of the groove-like recess 37 is reduced to reduce the groove-like recess 37. The width W2 of the thick portion 38 may be increased. In this case, since the width W1 of the flat surface portion 37a that is the bolt seat surface may be smaller than the diameter D1 of the head portion 13a of the stud bolt 13, a circular shape having a diameter D2 that is larger than the diameter D1 of the head portion 13a of the stud bolt 13. A bolt seat surface 61 of the stud bolt 13 is formed by pressing a position corresponding to the bolt fixing hole 33 a of the mounting flange 33 with a mold (not shown) having the flat surface portion 60. By doing in this way, since the width W2 of the thick part 38 of the mounting flange 33 can be enlarged, the strength of the mounting flange 33 can be further increased.

In addition, this invention is not limited to what was illustrated to the said embodiment, In the range which does not deviate from the summary of this invention, it can change suitably.
For example, in the above embodiment, the case where the present invention is applied to a wheel support hub unit for a driven wheel is illustrated, but the present invention is not limited to this, and the present invention is applied to a wheel support hub unit for a drive wheel. Also good.
Moreover, although the case where this invention was applied to the solid inner ring member was illustrated in the said embodiment, it is not limited to this, You may apply this invention to a hollow outer ring member.
Moreover, in the said embodiment, although the case where the attachment flange was formed in the outer peripheral surface of the axial part at intervals of 90 degrees in the circumferential direction was illustrated, it is not limited to this, and the present invention is changed to the number and arrangement of the attachment flanges. May be applied.

10 Wheel support hub unit 13 Stud bolt (mounting bolt)
13a Head 20 Outer ring member (Raceway ring member)
21 Outer ring raceway groove 22 Shaft portion 23 Mounting flange 23a Bolt insertion hole 30 Inner ring member (track ring member)
31 Inner ring raceway groove 32 Shaft portion 33 Mounting flange 33a Bolt fixing hole 34 Inner ring 35 Mounting surface 36 Anti-mounting surface 37 Groove-shaped recess 37a Flat portion 38 Thick portion 39 Bolt seat surface 40 Material 41 First intermediate material 42 Second intermediate material (Material)
43 Third intermediate material 44 Final intermediate material 50 Forging device 51 Lower die 52 Upper die 53 Ring punch 54 Press punch 55 Extrusion punch 56 Mounting plate 57 Elastic member 58 Shaft forming cavity 59 Flange forming cavity 60 Circular flat surface Part (flat part)
61 Bolt seating surface W1 Width of flat part D1 Diameter of head D2 Diameter of circular flat part

Claims (3)

A solid or hollow shaft portion, and a mounting flange that extends radially outward from the shaft portion and is attached to a wheel or a vehicle body,
A bearing ring member of a hub unit bearing in which the mounting flange is integrally molded with the shaft portion by cold side extrusion,
A groove-like recess is formed along the radial direction on the surface of the mounting flange opposite to the mounting surface to the wheel or the vehicle body,
The raceway member of a wheel-supporting hub unit, wherein the flat surface portion of the groove-shaped recess is a bolt seat surface of a mounting bolt for mounting the mounting flange to the wheel or the vehicle body. A method of manufacturing a bearing member of a wheel support hub unit having a solid or hollow shaft portion and a mounting flange extending radially outward from the shaft portion,
A shaft ring forming cavity for forming the shaft portion, and a radial extending from the shaft portion forming cavity radially outward from the material of the ring member, and forming the mounting flange Placing the mold in a mold having a flange forming cavity of
One end or both ends of the material are crushed at room temperature, and the material is caused to flow into the shaft-forming cavity and the flange-forming cavity of the mold, thereby radially extending along one axial surface thereof. And a step of forming the mounting flange formed with a groove-shaped recess integrally with the shaft portion by lateral extrusion, and a method of manufacturing a bearing member of a wheel support hub unit.   By pressing a predetermined position of the mounting flange with a mold having a flat portion having a width larger than the diameter of the head of the mounting bolt for mounting the mounting flange to a wheel or a vehicle body, the bolt seat surface of the mounting bolt is The method of manufacturing a bearing ring member for a wheel supporting hub unit according to claim 2, further comprising the step of forming.

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