JP2007218427A - Rolling bearing device and its assembling method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To simplify an assembly process by easily carrying out preload adjustment. <P>SOLUTION: In a third generation rolling bearing device, an inner ring 3 is attached to a small diameter part 22 in a one end side of an inner shaft 2. Screw parts 12, 13, and fitting parts 14, 15 to be fit by interference fit are provided on attachment contact surfaces of the small diameter part 22 of the inner shaft 2, and the inner ring 3. A preload is set by screwing the inner ring 3 to the small diameter part 22, changing screw depths of the screw parts 14, 15, and adjusting an axial position of the inner ring 3. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a third-generation rolling bearing device in which an inner ring is mounted on one end side of an inner shaft disposed on the inner periphery of an outer ring, and an assembling method thereof.

Conventionally, a hub unit is manufactured by assembling a shaft, an inner ring, a ball, and an outer ring (see Patent Document 1). In that case, variation in the measurement accuracy of the shaft, variation in the measurement accuracy of the inner ring, variation in the specifications of the ball, In order to cope with changes in the inner ring raceway dimensions due to press fitting of the inner ring into the shaft, changes in the dimensions of the shaft, inner ring, ball and outer ring depending on the temperature, etc., it is necessary to measure the dimensions of each individual part. It took a long time, which was an obstacle to shortening the manufacturing time of the hub unit and reducing the manufacturing cost.
JP-A-2-159536

  In the rolling bearing device as described above, not only high-precision machining dimensions are required for each member, but also the assembly man-hours such as measurement of the dimensions of each member increase, the assembly cycle time increases, and the production yield increases. As a result, the manufacturing cost is increased.

  A rolling bearing device according to the present invention is a rolling bearing device in which an inner ring is mounted on a small-diameter portion on one end side of an inner shaft, and the inner ring shaft is rotated by mutual screw rotation on a mounting contact surface between the small-diameter portion of the inner shaft and the inner ring. The present invention is characterized in that a screwing portion that enables adjustment of the directional position and a fitting portion that fits with an interference fit and concentrically couples the inner ring to the small diameter portion are provided.

  The fitting portion may be a fixing portion that fixes the small-diameter portion of the inner shaft and the inner ring, or a fixing portion by welding or adhesion may be provided separately from the fitting portion. Moreover, you may fix the small diameter part of an inner shaft, and an inner ring | wheel by expanding the diameter of the cylindrical part of a small diameter part outer end.

  According to the rolling bearing device of the present invention, the required preload or the axial clearance can be set by adjusting the screwing depth of the screwed part by screwing the inner ring with respect to the small diameter part of the inner shaft.

  In addition, it is possible to prevent or suppress a decrease in inner ring rigidity caused by backlash at the screwed portion and a center misalignment of the raceway surface of the inner ring at the fitting portion. As a result, it is possible to manage the pitch between the double-row tracks on the side with high precision and eliminate the need for caulking of the shaft end to give preload, resulting in a significant reduction in assembly man-hours and a reduction in manufacturing costs. Can do.

  In the rolling bearing device having the above-described configuration, it is desirable that the threaded portion of the inner ring is formed at a position that is axially deviated from the raceway portion of the inner ring, and more specifically, the inner ring has an inner end in the axial direction than the raceway portion. It is desirable that a screwing portion is provided on the side, and the fitting portion is formed on the outer end side in the axial direction from the screwing portion. In this way, when the threaded portion of the inner ring is in a position deviated from the track portion in the axial direction, the influence of the threaded portion on the track portion of the inner ring becomes extremely small.

  An assembly method for a rolling bearing device according to the present invention is an assembly method for assembling a rolling bearing device by mounting an inner ring on a small-diameter portion on one end side of an inner shaft, wherein the inner-ring-side threaded portion is engaged with a small-diameter-side threaded portion. The inner ring side fitting part is fitted to the fitting part on the small diameter part side with an interference fit, and the screwing depth of the screwing part of both parts by relative screw rotation between the small diameter part and the inner ring To adjust the preload or axial clearance, and by fitting both fitting parts between the small diameter part and the inner ring, it prevents the inner ring from lowering its rigidity due to the screwing of the screwed part, and the inner ring raceway surface. It is characterized by performing centering.

  According to the assembling method of the present invention, not only the burden of high-accuracy dimensional management of each member is reduced, but also the steps such as measuring the dimensions of each member can be omitted, the number of assembling steps is greatly reduced, and the assembly cycle is reduced. Time is shortened and manufacturing yield is improved.

  According to the present invention, it is possible to simply adjust the preload without reducing the rigidity of the portion where the inner ring is attached to the inner shaft and without causing the raceway portion of the inner ring to be misaligned with respect to the outer ring.

  Referring to the drawings, the best mode rolling bearing device according to the present invention will be described. FIG. 1 is a half sectional view of the rolling bearing device, and FIG. 2 is an exploded view of the main part of the rolling bearing device of FIG. It is an expanded sectional view.

  Referring to FIG. 1, the rolling bearing device includes an outer ring 1, an inner shaft 2, an inner ring 3, and balls 4 and 5 as rolling elements as a double row angular ball bearing type.

  The outer ring 1 includes a flange portion 11 for fixing to a member on the vehicle body side on the outer peripheral surface, and has track portions 1a and 1b in an axial double row on the inner peripheral surface. The inner shaft 2 has a large-diameter portion 21 on one side in the axial direction (left side in FIG. 1), and a small-diameter portion 22 on the other side in the axial direction (right side in FIG. 1). A radially outward flange portion 23 to be fixed and a single row raceway portion 2 a facing one raceway portion 1 a of the outer ring 1 are provided, and the inner race 3 is mounted on the outer periphery of the small-diameter portion 22. The inner ring 3 includes a single-row track portion 3 b that faces the other track portion 1 b of the outer ring 1.

  A plurality of balls 4, 5 are provided between one raceway portion 1 a of the outer ring 1 and the raceway portion 2 a of the inner shaft 2 and between the other raceway portion 1 b of the outer ring 1 and the raceway portion 3 b of the inner ring 3, respectively. It arrange | positions in the state hold | maintained at the holder | retainers 6 and 7. FIG. Seals 8 and 9 are respectively provided between one axial side of the outer ring 1 and the inner shaft 2 and between the other axial side of the outer ring 1 and the inner ring 3.

  With the above configuration, the rolling bearing device of the present invention can adjust the axial position of the inner ring 3 by rotating the inner ring 3 with respect to the inner shaft 2 on the mounting contact surface between the small diameter portion 22 of the inner shaft 2 and the inner ring 3. There is a feature in that screwed portions 12 and 13 are provided. As clearly shown in FIG. 2, the threaded portion 12 on the small diameter portion 22 side is formed of an external thread, and is formed on the outer peripheral surface of the small diameter portion 22 from the stage portion 2 c of the small diameter portion 22 to the middle position of the small diameter portion 22. The threaded portion 13 on the inner ring 3 side is formed of an internal thread, and is formed on the inner peripheral surface of the inner ring 3 at a position closer to the inner end side in the axial direction than the track portion 3b.

  By the way, in the configuration in which the small-diameter portion 22 of the inner shaft 2 and the inner ring 3 are screwed together by the screwing portions 12 and 13 as described above, the inner ring 3 is rattled due to backlash of the screw portion, and the rigidity is lowered. In addition, the core position of the raceway portion 3b of the inner ring 3 may be displaced with respect to the inner shaft 2. Therefore, the rolling bearing device according to the present invention is a fit in which the inner ring 3 is concentrically coupled to the small-diameter portion 22 of the inner shaft 2 by fitting with the fitting contact surface between the small-diameter portion 22 of the inner shaft 2 and the inner ring 3 with an interference fit. Another feature is that the joint portions 14 and 15 are provided. The fitting portions 14 and 15 are formed at a position closer to the outer end side in the axial direction than the screwing portions 12 and 13 and smaller in diameter than the screwing portions 12 and 13.

  The fitting portion 14 on the small diameter portion 22 side has a cylindrical outer peripheral surface, and is formed on the outer periphery of the small diameter portion 22 at a position on the outer end side in the axial direction from the screwing portion 12. The fitting portion 15 on the inner ring 3 side is formed of a cylindrical inner peripheral surface, and is formed at a position closer to the outer end side in the axial direction than the screwing portion 13 on the inner circumference of the inner ring 3. The inner ring 3 overlaps with the axial position of the track portion 3b. The fitting portion 15 on the inner ring 3 side is slightly smaller than the outer diameter D14 of the fitting portion 14 on the small diameter portion 22 side (specifically, so as to fit to the fitting portion 14 on the small diameter portion 22 side to the negative clearance. In particular, it has a small inner diameter d15 (D14> d15). On the outer end surface of the inner ring 3, recesses 16 are formed for engaging jigs for rotating operation at several places in the circumferential direction.

  Then, the inner ring 3 side screwing part 13 is screwed to the small diameter part 22 side screwing part 12 and the inner ring 3 side fitting part 15 is fitted to the small diameter part 22 side fitting part 14. The inner ring 3 is mounted on the small diameter portion 22, the outer end portion of the inner ring 3 mounted in this way and the outer end portion of the small diameter portion 22 are welded, and the inner ring 3 is fixed to the small diameter portion 22 by the welded portion 17. ing.

  In the rolling bearing device having the above configuration, the inner ring 3 is screw-rotated with respect to the small diameter portion 22 in a state where the inner ring 3 is screwed to the small diameter portion 22 of the inner shaft 2, and the screwed portions 12 and 13 are screwed together. By changing the depth, the axial position of the inner ring 3 can be finely adjusted, and the preload or the axial clearance can be set to a predetermined value. After the preload or the axial clearance is set, the inner ring 3 may be fixed to the small diameter portion 22 of the inner shaft 2.

  In addition, a decrease in rigidity of the inner ring 3 caused by screwing between the small-diameter portion 22 of the inner shaft 2 and the inner ring 3 and a misalignment of the inner ring raceway portion 3b are prevented or suppressed by the fitting of the fitting portions 14 and 15, so that the inner ring 3 is fixed concentrically and integrally with the small diameter portion 22 of the inner shaft 2.

  As shown in the embodiment, when the fitting portion 15 is positioned on the inner peripheral side of the raceway portion 3b of the inner ring 3, the influence of the screwing portion 13 hardly appears on the raceway portion 3b, and the raceway portion 3b Misalignment can be reliably prevented.

  FIG. 3 is a cross-sectional view of a main part of a rolling bearing device according to another embodiment of the present invention. In this embodiment, the threaded portion 13 on the inner ring 3 side is screwed into the threaded portion 12 on the small diameter portion 22 side of the inner shaft 2, and the fitting portion on the inner ring 3 side is fitted on the fitting portion 14 on the small diameter portion 22 side. 15, the inner ring 3 is attached to the small-diameter portion 22, and then the diameter of the cylindrical portion 22 a on the outer end side in the axial direction of the small-diameter portion 22 is increased by pressing the tapered diameter-enlarging jig G. The inner ring 3 is fixed to the small diameter portion 22. The diameter expansion jig G may be a small angle, for example, an expansion angle of 10 degrees or less. What is necessary is just to adjust the amount of diameter expansion of the cylinder part 22a of the small diameter part 22 by setting the pushing depth of the diameter expansion jig G suitably.

  In addition, in order to fix the inner ring 3 to the small-diameter portion 22 of the inner shaft 2, an adhesive, for example, an adhesive filled between the screw fitting portions may be used, or the small-diameter portion 22 and the inner ring 3 The fitting portions 14 and 15 may serve as a fixing portion between the small diameter portion 22 and the inner ring 3.

  The positional relationship between the screwing portions 12 and 13 and the fitting portions 14 and 15 is not limited to the example shown in the figure, and the fitting portions 14 and 15 are provided at positions inward in the axial direction, and the outer end side in the axial direction than this. The screwing portions 12 and 13 may be formed at a smaller diameter than the fitting portions 14 and 15 at the positions. Moreover, you may make it the shape which combined both.

  The present invention can also be implemented in a rolling bearing device for a drive wheel in which a drive shaft is inserted and fixed in a shaft hole in the central portion of the inner shaft. Further, the present invention can be applied not only to the ball bearing type rolling bearing device but also to other types, for example, a rolling bearing device using a tapered roller.

1 is a half sectional view of a rolling bearing device according to the best mode for carrying out the present invention. The expanded sectional view which decomposed | disassembled and showed the principal part of the rolling bearing apparatus of FIG. Sectional drawing of the principal part of the rolling bearing apparatus which concerns on other embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Outer ring 2 Inner shaft 22 Small diameter part 3 Inner ring 12 Small diameter part screwing part 13 Inner ring side screwing part 14 Small diameter part fitting part 15 Inner ring side fitting part

Claims (3)

A rolling bearing device in which an inner ring is attached to a small diameter portion on one end side of an inner shaft,
The inner ring is concentrically connected to the small diameter part by fitting with a threaded part that allows adjustment of the axial position of the inner ring by mutual screw rotation on the mounting contact surface between the small diameter part of the inner shaft and the inner ring. A rolling bearing device, characterized in that a fitting portion is provided.   2. The rolling according to claim 1, wherein the inner ring is provided with a threaded portion closer to the inner end side in the axial direction than the track portion, and a fitting portion is formed closer to the outer end side in the axial direction than the threaded portion. Bearing device. An assembly method for assembling a rolling bearing device by attaching an inner ring to a small diameter portion on one end side of an inner shaft,
The inner ring side screwing part is screwed to the small diameter part side screwing part, and the inner ring side fitting part is fitted to the small diameter part side fitting part with interference fit,
Set the preload or axial clearance by adjusting the screwing depth of the screwed part of the small diameter part and the inner ring by relative screw rotation,
By fitting both fitting portions of the small diameter portion and the inner ring, the inner ring rigidity is prevented from being lowered due to the screwing of the screwed portion, and the raceway surface of the inner ring is centered.
A method for assembling a rolling bearing device.

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