JP2007255600A - Transportation method of hub unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a transportation method of a hub unit preventing the occurrence of fretting wear caused by vibration during transportation due to lubrication failure and the occurrence of dummy dents in a bearing raceway part. <P>SOLUTION: In the case the hub unit 1 is assembled to a vehicle 91 such as an automobile and transported, a heater 60 is mounted on an outer peripheral face of an outer ring 22 of the hub unit 1. In a state of the periphery of the raceway part being heated by the heater 60, the hub unit 1 is transported by a freight car 90, a vessel, or a truck. Because the periphery of the raceway is heated by the heater 60, lubricating performance of grease is maintained, fretting wear due to minute vibrations is prevented, and the occurrence of dummy dents is prevented. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a method for transporting a hub unit.

  Conventionally, a hub unit for attaching a tire wheel and a brake disk is used in a vehicle such as an automobile. When a vehicle such as an automobile is transported by a freight car, a ship, or the like, minute vibrations cause the hub unit of the vehicle to vibrate, generate fretting wear, generate wear powder, and generate a pseudo indentation in the track portion. The wear powder is oxidized to iron oxide, and the iron oxide further promotes wear, and the pseudo indentation is enlarged.

  As a preventive measure, claw gaps are implemented. In addition, it is disclosed that a portion extending from the inner ring raceway surface to the root portion of the flange in the surface portion of the hub ring is a hardened portion by high-frequency heat treatment (Patent Document 1).

JP-A-11-51064

  When a vehicle equipped with a hub unit in which pseudo-indentation is generated due to fretting wear during transportation is generated, noise is generated, and the pseudo-indentation also affects the life of the hub unit. The prevention effect is poor, and if it is made into a hardening process part like patent document 1, an increase in production cost will be caused.

  By the way, the fretting wear described above is likely to occur during transportation of a freight car in a cold region. This is due to the poor lubricity of the grease in the raceway in cold regions.

  An object of the present invention is to provide a hub unit transportation method that prevents occurrence of fretting wear due to vibration during transportation due to poor lubrication and prevents generation of pseudo indentation in a bearing race.

Means for Solving the Problems and Effects of the Invention

The transport method of the hub unit of the present invention for solving the above problems is as follows.
An outer ring that is non-rotatably attached to the vehicle body side, and a hub wheel that is arranged concentrically with the outer ring and that is provided on the outer ring via a rolling element so as to be rotatable around an axis center and is attached to a vehicle wheel and rotates integrally A hub unit transport method comprising:
A heating mechanism for heating the grease arranged with the rolling elements in the rolling element arrangement space formed by the outer ring and the hub wheel is provided in the outer ring,
The hub unit assembled in the vehicle body is heated to a predetermined temperature by a heating mechanism and transported in a state where vibration is applied to the hub unit.

  According to the above method, the grease arranged with the rolling elements in the rolling element arrangement space can be heated by the heating mechanism, whereby the lubricity of the grease can be improved. For example, even when a hub unit assembled in a vehicle body is transported in a cold region, since the grease is heated to a predetermined temperature and the lubricity is good, fretting due to vibration during transportation etc. The occurrence of wear can be prevented.

  And the heating mechanism in the transportation method of the hub unit of this invention can be comprised with the heater which covers the outer peripheral surface of an outer ring | wheel. Specifically, the grease is heated by winding a belt-like heater around the outer circumferential surface of the outer ring. By such a method, it is possible to heat the grease arranged together with the rolling elements in the rolling element arrangement space formed by the outer ring and the hub wheel, and the grease is heated to a predetermined temperature so that the lubricity is good. Therefore, the occurrence of fretting wear due to vibration during transportation can be prevented.

  More specifically, the rolling elements are arranged in a double row in the axial direction, and the inter-row gap between the rolling elements is a grease holding space, and a heater is provided on the outer peripheral surface of the outer ring corresponding to the grease holding space in the axial direction. Wrap. Grease can be more effectively heated by winding a heater on the outer peripheral surface of the outer ring corresponding to the grease holding space in the axial direction.

  Then, at least a part of the outer peripheral surface of the outer ring corresponding to the grease holding space in the axial direction can be formed as a cylindrical surface centered on the shaft center, and a belt-like heater can be wound around the cylindrical surface. In this way, by forming a part of the outer peripheral surface of the outer ring of the hub unit as a cylindrical surface centering on the shaft center, the belt-like heater can be tightly wound around the outer ring, and the grease can be more effectively applied. Can be heated.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a cross-sectional view of the hub unit 1 in the present embodiment. In the figure, the right side is the vehicle outer side, and the left side is the vehicle inner side. As shown in FIG. 1, the hub unit 1 includes a rolling bearing (outer ring member) 2 and a hub wheel (inner ring member) 3 arranged concentrically with the rolling bearing 2.

  The hub wheel 3 includes a shaft portion 11 that is a hub wheel main body portion, and a hub flange 12 that fixes a wheel and a brake disc. A rolling bearing 2 formed of an angular ball bearing is mounted on the outer periphery of the shaft portion 11. The hub flange 12 protrudes in the radial direction from the end portion of the outer peripheral surface of the hub wheel 3 on the vehicle outer side, and is formed integrally with the shaft portion 11. The hub wheel 3 is formed by hot forging from carbon steel for mechanical structure such as S55C.

  The rolling bearing 2 includes an inner ring 21 serving as a rotating track that is press-fitted into the outer periphery of the shaft 11 on the vehicle inner side and fixed by caulking 33, and an outer ring 22 serving as a fixed ring. In addition, two rows of rolling elements 27 that are arranged to roll along inner ring raceways 23 and 24 formed on the shaft 11 and the inner ring 21 and outer ring raceways 25 and 26 formed on the outer ring 22, and each row A crown-shaped cage 28 that holds the rolling elements 27 and a seal member 29 that is fixed to the outer ring 22 on the side of the hub flange 12 and interposed between the shaft portion 11.

  The seal member 29 is attached to a vehicle outer side end portion of the outer ring 22, and prevents grease in the rolling element arrangement space 16 formed by the outer ring 22 and the hub wheel 3 from leaking to the outside, and the hub flange 12 and the outer ring. The muddy water is prevented from entering the rolling element arrangement space 16 from between the two.

  The outer ring 22 is made of hot forged carbon steel for machine structure such as S55C, and an outer ring flange portion 30 having a bolt insertion hole 31 is provided on the outer peripheral surface thereof, and an outer ring inlay portion 35 is formed on the vehicle inner side. ing.

  The carrier 13 is brought into contact with the outer ring inlay portion 35 to position the hub unit 1 with respect to the carrier 13, and the outer ring 22 is fixed to the carrier 13 by inserting a bolt into the bolt insertion hole 31 of the outer ring flange portion 30. The unit 1 is fixed to the vehicle body. Then, the wheel is rotatably supported with respect to the vehicle body via the rolling bearing 2.

  In the hub unit 1, a sensor rotor 41 having a detected portion is press-fitted and fixed to the hub wheel 3. A cover 44 provided with a magnetic sensor 53 as a rotation detector is press-fitted into the outer ring 22. In the cover 44, a stopper portion 48 is formed on the outer side in the radial direction of a cylindrical portion 45 formed in a cylindrical shape. The axial end surface 35s can be used as an engaging surface for other members, and the stopper portion 48 is engaged with the axial end surface 35s of the outer ring inlay portion 35, and the cover 44 is attached to the inner peripheral surface of the outer ring inlay portion 35. It has been. The sensor rotor 41 includes an annular cored bar 42 and a magnetic body 43. The magnetic sensor 53 includes a magnetic detection element 52 and the like. The rotation detector detects the rotation speed and direction of the wheel.

  As described above, the stopper portion 48 formed on the cylindrical portion 45 of the cover 44 can be engaged with the axial end surface 35s, and the axial end surface 35s can be used as a stopper surface. The hub unit 1 is not limited to the carrier 57 but may be a knuckle or the like as a vehicle body side support member.

  The inner ring on the vehicle outer (hub flange 12) side is formed integrally with the shaft portion 11 by forming an inner ring raceway 23 on the shaft portion 11 of the hub wheel 3. Further, the inner ring 21 on the vehicle inner side is formed separately from the shaft portion 11. The inner ring is made of high carbon chrome bearing steel such as SUJ2.

  The vehicle outer side main surface 18 of the hub flange (flange portion) 12 of the hub wheel 3 is formed to be flush with the insertion hole 15 for inserting the hub bolt 38 into a predetermined position of the hub flange 12. In the hub flange 12, an inlay portion 7 that guides the mounting position in the radial direction of the brake disc rotor and the tire wheel is formed on the vehicle outer side main surface 18 so as to protrude in the axial direction.

  A flexible belt-shaped heater 60 is wound around the outer peripheral surface of the outer ring 22 of the hub unit 1, and the heater 60 is connected to a power supply unit 62 by a conducting wire 61. Although the heater 60 will not be specifically limited if it can cover the outer peripheral surface of the outer ring | wheel 22, For example, a silicon rubber heater can be used.

  FIG. 2 shows a silicon rubber heater. FIG. 2A is a sectional view of the silicon rubber heater, and FIG. 2B is a plan view. The silicon rubber heater has a structure in which two silicon rubber sheets 64, which are insulating materials, are sandwiched between two upper and lower glass cloths 65. Furthermore, the silicon rubber heater generates heat in a form sandwiched between the silicon rubber sheets 64. A nickel alloy resistance wire that forms the body 63 is patterned and embedded. Two silicon rubber sheets 64 are compression-pressed and finally heated and cured to be integrated into a sheet shape.

  The silicon rubber heater is filled and reinforced with a glass cloth 65 on the exterior, and is flexible and excellent in mechanical strength. Moreover, since it is a thin sheet form, it has excellent thermal responsiveness and is suitable for the transportation method of the hub unit 1 of the present invention.

  The silicon rubber heater can be attached to the hub unit 1 using a double-sided tape, a silicon adhesive, a band, a metal fitting, or a spring.

  As shown in FIG. 1, in the hub unit 1, the rolling elements 27 are arranged in a double row in the axial direction, and the inter-row gaps 14 between the rolling elements are used as a grease holding space to hold the grease. Then, a belt-like heater 60 is wound around the outer peripheral surface of the outer ring corresponding to the grease holding space in the axial direction, and the grease held in the inter-row gap 14 is heated to 10 ° C. or higher and 30 ° C. or lower. As a result, the lubricity of the grease can be improved. For example, in a cold region, the hub unit assembled in the vehicle body is vibrated (particularly caused by vibration in the radial direction, but not limited thereto). Even when transporting while being added to the hub unit, it is possible to prevent the occurrence of fretting wear due to vibration during transportation due to poor lubrication. The grease is preferably heated to 10 ° C. or higher in order to improve the lubricity of the grease. When the temperature exceeds 30 ° C., power consumption increases. However, the effect for preventing poor lubrication is not different from the case where the temperature is 30 ° C. or lower.

  FIG. 3 shows another embodiment of a method for attaching the heater 60 to the outer ring 22. As shown in FIG. 3A, the heater 60 may be attached so as to widely cover the outer peripheral surface of the outer ring 22 so as to heat the vicinity of the inter-row space 14 between the rolling elements. Or as shown in FIG.3 (b), you may make it attach two heaters 60 to the outer peripheral surface of the outer ring | wheel 22 so that a rolling element periphery may be heated. By attaching the heater 60 in this way, the periphery of the tracks 23, 24, 25, and 26 is heated, the grease lubricity is improved, fretting wear is prevented, and pseudo indentation is prevented. be able to.

  FIG. 4 shows a hub unit 71 in which at least a part of the outer peripheral surface of the outer ring 22 corresponding to the grease holding space in the axial direction is formed as a cylindrical surface 22c centering on the axis. A belt-like heater 60 is wound around the cylindrical surface 22 c of the hub unit 71.

  As described above, the hub unit 71 is formed such that the outer peripheral surface of the outer ring 22 has a different diameter in the axial direction. Specifically, the end portion on the vehicle outer side in the axial direction is formed as a thin portion 22a because the seal member 29 is provided, and the vehicle inner side is formed as a thick portion 22b in order to give strength. The outer peripheral surface is formed to be inclined in the axial direction so that the diameter decreases from the thick portion 22b to the thin portion 22a. Therefore, in the hub unit 1 described above, the belt-like heater 60 is not tightly wound around the outer peripheral surface, but in the hub unit 71 of FIG. 4, the outer peripheral surface of the outer ring 22 corresponding to the grease holding space in the axial direction. Since at least a part of is formed as a cylindrical surface 22c centering on the axis, the belt-shaped heater 60 can be wound around the cylindrical surface 22c.

  In the hub units 1 and 71, a heater 60 is wound around the outer ring 22, and the vehicle is assembled with a vehicle 91 such as an automobile and heated by the heater 60, and as shown in FIG. Since the grease lubricity of the tracks 23, 24, 25, and 26 is maintained when transported by the fretting, fretting due to minute vibration (particularly, but not limited to, vibration in the radial direction). Abrasion can be prevented and generation of pseudo indentation can be prevented.

  As described above, the hub units 1 and 71 assembled in the vehicle body are wound around the belt-shaped heater 60 in the circumferential direction of the outer peripheral surface of the outer ring 22, and the heater 60 and the rolling elements are placed in the rolling element arrangement space 16. By heating the disposed grease, it is possible to improve the lubricity of the grease, to prevent fretting wear due to minute vibrations, and to prevent generation of pseudo indentation.

  In the above description, the heater 60 is formed in the shape of a belt and wound around the outer ring 22. However, the heater installation hole may be formed in the outer ring 22 and the heater 60 may be installed in the heater installation hole.

  So far, means for preventing fretting wear due to poor lubrication during transportation of the hub unit have been disclosed, but the present invention is not limited to transportation of the hub unit wagon. That is, since fretting wear occurs even during normal vehicle travel, this means can be used continuously after the hub unit is transported.

Sectional drawing which shows the hub unit as one Example of this invention. The figure explaining one Example of a heater. The figure explaining the other Example of attachment of a heater. The figure which shows the hub unit in which the cylindrical part was formed. The figure which shows the transport method of the hub unit transported in the state attached to the vehicle.

Explanation of symbols

1 Hub unit 2 Rolling bearing (outer ring member)
3 Hub wheel (inner ring member)
14 Space between rows 16 Rolling element arrangement space 21 Inner ring 22 Outer ring 22c Cylindrical surfaces 23 and 24 Inner ring raceways 25 and 26 Outer ring raceway 27 Rolling element 29 Seal member 41 Sensor rotor 44 Cover 53 Magnetic sensor 60 Heater 63 Heating element 64 Silicon rubber sheet 65 Glass cloth 71 Hub unit 90 Freight car 91 Vehicle

Claims (5)

An outer wheel that is non-rotatably attached to the vehicle body side, and a hub wheel that is arranged concentrically with the outer ring and that is rotatably provided around the axis of the outer ring via a rolling element and is attached to a vehicle wheel and rotates integrally therewith. A method for transporting a hub unit comprising:
A heating mechanism for heating the grease disposed with the rolling elements in a rolling element arrangement space formed by the outer ring and the hub wheel is provided in the outer ring,
A hub unit transporting method, wherein the hub unit in a state of being assembled to the vehicle body is transported in a state where the hub unit is heated to a predetermined temperature by the heating mechanism and vibration is applied to the hub unit.   The method of transporting a hub unit according to claim 1, wherein the heating mechanism is a heater that covers an outer peripheral surface of the outer ring.   The method for transporting a hub unit according to claim 2, wherein the belt-shaped heater is wound around the outer circumferential surface of the outer ring.   The rolling elements are arranged in a double row in the axial direction, the inter-row gap between the rolling elements is a grease holding space, and the heater is provided on the outer peripheral surface of the outer ring corresponding to the grease holding space in the axial direction. The method for transporting a hub unit according to claim 2 or 3, wherein the hub unit is wound.   5. At least a part of the outer peripheral surface of the outer ring corresponding to the grease holding space in the axial direction is formed as a cylindrical surface centered on the axis, and the belt-shaped heater is wound around the cylindrical surface. The transportation method of the hub unit described in 1.

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