JP2000087976A - Bearing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stabilize the slip off resistance by a caulked part before the caulking by providing a contracted diameter part on a shaft body before caulking. SOLUTION: The rigidity of a shaft body 1 is gradually reduced from a contraction starting point to a free end by providing a contracted diameter part 14 which is contracted toward the free end side on an area from an arbitrary position in a bearing fitting area of the shaft body 1 before caulking to the free end of the shaft body 1. The deformation starting point due to the rolling caulking in the shaft body 1 is fixed to the diameter contraction starting point in the bearing fitting area of the shaft body 1, and the part to be deformed is easily, uniformly and tightly attached from an inner circumferential surface of an inner ring 21 to an outer end face. A caulked part 3 of a constantly stable shape can be obtained thereby.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bearing device in which a rolling bearing is mounted on a shaft.

[0002]

2. Description of the Related Art As an example of this type of conventional bearing device,
There is a vehicle hub unit as shown in FIG.

In the illustrated vehicle hub unit B, a double-row outwardly angular contact ball bearing 82 is externally fitted to a shaft portion 81 of a hub wheel 80 as a shaft body, and the free end of the shaft portion 81 is subjected to rolling caulking. Swell and deform radially outward,
By pressing the swollen and swaged portion 85 against the outer end surface of the inner ring 84 of the bearing 82, the hub wheel 8
The bearing 82 is fixed at 0 to prevent it from falling off.

The shape of the shaft portion 81 of the hub wheel 80 before caulking has an outer diameter uniform at each position in the axial direction, as shown by a virtual line in FIG. The free end of the shaft portion 81 is rolled and caulked using a caulking jig 90 as shown in FIG. At this time, the tip of the caulking jig 90 is applied to the shaft portion 81, and the caulking jig 90 is rolled around the dashed line O. As a result, the free end of the shaft portion 81 is swelled and deformed outward in the radial direction, and the inner ring 84 is prevented from falling off by the swaged caulked portion 85.

[0005]

In the above conventional example, since the outer diameter of the shaft portion 81 is set uniformly at each position in the axial direction before caulking, when the free end of the shaft portion 81 is rolled and caulked. The position of the deformation starting point varies from time to time, and when severe, the caulking portion 85
May not be uniformly adhered. In such a case, the shape of the caulked portion 85 becomes unstable, which may result in insufficient pull-out drag.

In addition, when the inner ring 84 is externally fitted to the shaft portion 81, when the inner ring 84 is press-fitted, the press-fitting distance becomes longer due to the formation of the caulking portion 85 as shown in FIG. Therefore, the outer peripheral surface of the shaft 81 and the inner ring 84
Is likely to be galled on the inner peripheral surface.

[0007] Accordingly, an object of the present invention is to stabilize the pull-out drag of a caulked portion in a bearing device.

[0008]

According to a first aspect of the present invention, there is provided a bearing device in which a rolling bearing is externally mounted on a shaft body, and the free end side of the shaft body is radially outwardly bulged and deformed by rolling caulking. Then, the swollen and deformed caulked portion is pressed against the outer end face of the inner ring of the rolling bearing to fix the rolling bearing to the shaft body, and before the caulking, the shaft body is formed on the outer peripheral surface thereof. In a region from an arbitrary position in the bearing mounting region to a free end of the shaft body, a reduced diameter portion that decreases in diameter toward the free end is provided.

According to a second aspect of the present invention, in the bearing device according to the first aspect of the present invention, the diameter-reduced portion of the first diameter-reduced portion is moved from an end position closer to a free end of the shaft to an inner ring raceway in a bearing mounting region on the outer periphery of the shaft. It is specified in the range up to the axial center position of the surface.

In the configuration of the present invention, in short,
By providing the reduced diameter portion on the shaft body, the rigidity tends to gradually decrease from the diameter reduction starting point to the free end, but the deformation starting point by rolling caulking is reduced to the bearing mounting area of the shaft body. The inner ring is fixed to the diameter reduction starting point, and the deformed portion is easily and uniformly adhered from the inner peripheral surface to the outer end surface of the inner race. This allows
It is possible to always obtain a caulked portion having a stable shape.
In addition, even when the inner ring is press-fitted onto the shaft body, the reduced diameter portion shortens the substantial press-fit distance of the inner ring, so that the occurrence of galling on the outer circumferential surface of the shaft body and the inner circumferential surface of the inner ring can be suppressed. .

In particular, in the case of claim 2, since the deformation origin is defined to be outside the axial center of the inner ring raceway surface, the stress caused by rolling caulking acts on the raceway center of the inner ring. It becomes difficult to do. Thereby, the contact form of the rolling element with the inner ring can be stably maintained.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the present invention will be described based on embodiments shown in the drawings. Here, a vehicle hub unit will be described as an example of the bearing device.

FIGS. 1 and 2 relate to an embodiment of the present invention. FIG. 1 is a longitudinal sectional side view of a vehicle hub unit.
FIG. 2 is a side view showing a state before swaging in FIG. 1.

In the figure, A indicates the entirety of a vehicle hub unit as a bearing device, 1 is a hub wheel as a shaft, 2 is a double row outward angular ball bearing as a rolling bearing, and 3 is a swaged portion. It is.

The hub wheel 1 is provided with an annular plate portion 11 on which wheels (not shown) are mounted, and a double-row outward-facing angular ball bearing 2, and for fixing the double-row outward-facing angular ball bearing 2 to the shaft end. A shaft portion 12 on which the caulking portion 3 is formed.

The double-row outward-facing angular contact ball bearing 2 comprises a shaft 1
An inner ring 21 having a single race fitted to the outer peripheral surface 12a of two small diameters, a single outer race 22 having two rows of race grooves, a plurality of balls 23 arranged in two rows, and two crowns Shape holder 2
4 and 25, and the large-diameter outer peripheral surface 12b of the shaft portion 12 of the hub wheel 1 described above is used as one inner ring. A radially outward flange 26 is provided on the outer periphery of the outer race 22, and is non-rotatably attached to an axle case or the like (not shown) via the flange 26.

This embodiment is characterized by the shape of the shaft portion 12 of the hub wheel 1 before swaging.

That is, the free end of the small-diameter portion 12a of the shaft portion 12 is provided with a concave portion 13 for obtaining the caulked portion 3, and the shaft is moved from an arbitrary position within the bearing mounting region 12c at the small-diameter portion 12a. In a region up to the free end of the portion 12, a reduced diameter portion 14 that reduces the diameter toward the free end side is provided. The diameter reduction starting point Y of the reduced diameter portion 14 is specified in a range W from the edge position near the free end of the shaft portion 12 to the axial center position X of the inner ring 21 raceway groove in the bearing mounting region 12c.

After the inner ring 21 is externally fitted to the small-diameter portion 12a of the shaft portion 12 of the hub wheel 1 by press-fitting, the free end of the shaft portion 12 is used for explanation in the prior art as shown in FIG. Roll caulking using a caulking jig 90 as shown in FIG. At this time, the tip of the caulking jig 90 is
2 and the caulking jig 90 is rolled around the dashed line O. As a result, the free end of the shaft portion 12 is bulged outward in the radial direction, and the swaged caulked portion 3 prevents the inner ring 21 from coming off.

Here, by providing the reduced diameter portion 14 on the shaft portion 12, the rigidity thereof tends to gradually decrease from the diameter reduction starting point Y to the free end, but slightly decreases. The deformation starting point is fixed to the diameter reduction starting point Y in the bearing mounting region 12c of the shaft portion 12, so that the deformed portion is easily and uniformly adhered from the inner peripheral surface to the outer end surface of the inner ring 21. Thereby, it becomes possible to always obtain the caulked portion 3 having a stable shape. In addition, when the inner ring 21 is press-fitted, the diameter of the reduced diameter portion 14 shortens the substantial press-fit distance of the inner ring 21.
Of the inner peripheral surface of the inner ring 21 and the inner peripheral surface of the inner ring 21 can be suppressed.

Also, as in this embodiment, the diameter reduction starting point Y
Is defined outside the axial center X of the raceway groove of the inner race 21, since the stress caused by rolling caulking is less likely to act on the raceway center X of the inner race 21,
The contact form of the ball 23 with the inner ring 21 can be kept stable.

As described above, during rolling caulking, the deformation starting point Y can be specified by devising the shape of the shaft portion 12, so that the caulking portion 3 having a stable shape can always be obtained. Became. This makes it possible to always stably secure the pull-out resistance, which can contribute to the improvement in the reliability of swaging.

It should be noted that the present invention is not limited to only the above-described embodiment, and various applications and modifications are conceivable.

(1) In the above embodiment, the reduced diameter portion 1
The diameter reduction amount of 4, ie, the diameter reduction angle θ, can be appropriately set in relation to the thickness of the free end of the shaft portion 12.

(2) In the above embodiment, the vehicle hub unit is taken as an example of the bearing device. However, the bearing device may be, for example, a guide roller for a sliding door of an automobile or the like and other bearing devices in general.

[0026]

According to the first and second aspects of the present invention, by providing a reduced diameter portion on the shaft body before caulking, the rigidity is gradually reduced from the starting point of the diameter reduction toward the free end, but gradually. As a result, the starting point of deformation due to rolling caulking can be specified as the starting point of diameter reduction in the bearing mounting area of the shaft, and the deformed portion can be easily uniformly contacted from the inner peripheral surface to the outer end surface of the inner ring. Become. As a result, a caulked portion having a stable shape can always be obtained, and the pull-out force of the caulked portion can be always stably secured, thereby contributing to an improvement in the reliability of the caulking.

In addition, even when the inner ring is press-fitted and fitted to the shaft body, since the substantial press-fit distance of the inner ring is shortened by the reduced diameter portion, the occurrence of galling on the outer peripheral surface of the shaft body and the inner peripheral surface of the inner ring can be suppressed. Become like

In particular, according to the second aspect of the present invention, since the deformation starting point is defined so as to be outside the axial center of the inner raceway surface, the stress caused by rolling caulking acts on the raceway center of the inner raceway. It becomes difficult to do. This makes it possible to stably maintain the contact form of the rolling element with the inner ring, thereby contributing to the improvement of the reliability of the bearing device, such as ensuring the stable operation of the rolling bearing.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional side view of a vehicle hub unit according to an embodiment of the present invention.

FIG. 2 is an enlarged view of a main part showing a state before swaging in FIG. 1;

FIG. 3 is a longitudinal sectional side view of a conventional vehicle hub unit.

FIG. 4 is an enlarged view of a main part showing a state before swaging in FIG. 3;

FIG. 5 is an explanatory view showing a rolling caulking mode.

[Explanation of symbols]

 Reference Signs List A Vehicle hub unit 1 Hub wheel 12 Hub wheel shaft portion 12c Hub wheel bearing mounting area 14 Shaft reduced diameter portion 2 Double row outward-facing angular contact ball bearing 21 Bearing inner ring 3 Swaged portion X Axial direction of inner ring raceway surface Starting point of diameter reduction of center Y-axis

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kazutoshi Toda 3-5-8 Minamisenba, Chuo-ku, Osaka-shi Inside Koyo Seiko Co., Ltd. (72) Inventor Tadashi Mitarai 3-58-8 Minamisenba, Chuo-ku, Osaka-shi Within Seiko Co., Ltd. (72) Inventor Shinichiro Kashiwagi 3-5-8 Minamisenba, Chuo-ku, Osaka-shi Koyo Seiko Co., Ltd. F-term (reference) 3J101 AA03 AA32 AA43 AA54 AA62 AA72 BA53 BA65 BA77 DA20 FA31 FA44 GA02

Claims (2)

[Claims] A rolling bearing is externally fitted to a shaft body, and the free end side of the shaft body is radially outwardly swelled by rolling caulking, and the swollen deformed caulked portion is formed on an inner ring of the rolling bearing. A bearing device in which the rolling bearing is retained and fixed to the shaft body by pressing against the outer end surface of the shaft body, wherein the shaft body is mounted on the outer peripheral surface of the shaft body from an arbitrary position in the bearing mounting region on the outer peripheral surface before caulking. In the area up to the free end,
A bearing device having a reduced diameter portion that decreases in diameter toward the free end side. 2. The bearing device according to claim 1, wherein the diameter-reduced portion of the diameter-reduced portion starts from an edge position near a free end of the shaft in a bearing mounting area on an outer peripheral surface of the shaft, and a shaft on an inner ring raceway surface. A bearing device specified in a range up to a center position in a direction.