JP2002002209A - Caster - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate reduction in cost and labor for manufacture by directly securing bearings to a yoke without bearing cases to reduce the number of parts. SOLUTION: This caster is provided with A: a press-formed yoke 3 shaped as one body comprising right/left supporters 32 formed and forked off into two branches, a central piece 31 connecting both upper ends of the 31 each other, and a nearly cylindrical recessed section 33 hollowed downward, B: right/ left supporters 32 of the yoke 3, a wheel 4 maintained freely-rotatable, C: a bearing 7 put in the recessed section 33 of the yoke 3 in which an outer ring is secured to the yoke 3 by caulking the outer circumference 33c of the recessed section 33, and D: a base 2 on which the yoke 3 is rotatably mounted via a swivel 6 secured to an inner ring 71 of the bearing 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a caster installed on a lower part of a truck or the like.

[0002]

2. Description of the Related Art In a field where quietness is required, for example, in a hospital or a convenience store that is open 24 hours a day when carrying luggage at night, it is necessary to take measures against noise of casters.
Therefore, when a yoke for rotatably holding a wheel is rotatably held about a turning shaft with respect to a base, a ball bearing is interposed between the turning shaft and the yoke. That is, a caster described in JP-A-11-245607 is known.

The caster described in this publication, as shown in FIG. 9, has a base A and an inner ring of a ball bearing C fixed to a turning shaft D, and a yoke B attached to a bearing case E fixed to an outer ring of the ball bearing C. By fixing the upper plate b1, the upper plate b1 of the yoke is rotatably attached to the lower side of the pedestal A via a ball bearing C.

[0004]

However, in the conventional configuration, the ball bearing is fixed to the upper plate of the yoke through a bearing case. That is, since the bearing case is substantially cylindrical and its peripheral side wall is bent so as to form a substantially U-shaped groove opened to the inner peripheral side, the outer ring of the bearing is held by the substantially U-shaped groove. It was held like a frog. The upper end of the bearing case is folded back to the outer periphery, and the folded portion sandwiches the upper plate of the yoke and is fixed to the yoke.

As described above, in the conventional configuration, a bearing case separate from the yoke is required to mount the ball bearing on the upper plate of the yoke. Therefore, the number of parts increases, and it takes time and effort to process each part and to assemble both parts. In addition, since the yoke and the bearing case are separate bodies, there is a possibility that rattling may occur unless the two members are correctly attached.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and its main purpose is to directly hold a bearing on a yoke itself, thereby reducing the number of parts, reducing the labor and cost of production, and Another object of the present invention is to provide a caster that is excellent in quality and quietness.

[0007]

In order to achieve the above object, a caster according to the present invention is characterized in that a bearing is accommodated in a concave portion formed in a yoke of a press-formed product, and an outer peripheral portion of the concave portion is caulked. Is mounted on the yoke, and a turning shaft is mounted on the inner ring of the bearing, and the yoke is rotatable with respect to the pedestal about the turning shaft.

More specifically, for example, it is a caster having the following elements. (1) A press-formed product in which a substantially cylindrical concave portion is integrally formed in a central piece which is bifurcated downward and connects upper end portions of left and right support pieces formed by bifurcation. York. (2) A wheel rotatably held between left and right support pieces of the yoke. (3) A bearing that is accommodated in the recess of the yoke, the outer peripheral portion of the recess is caulked, and the outer ring is fixed to the yoke. (4) A pedestal on which the yoke is rotatably mounted via a turning shaft fixed to the inner ring of the bearing.

Preferably, a pedestal, and a yoke rotatably mounted on the pedestal about a pivot axis,
A wheel rotatably mounted on the yoke, wherein the yoke is formed by press-forming a steel plate, and has an upper central piece in which a substantially cylindrical recess for accommodating a bearing is recessed downward. In the bearing arranged in the recess, the outer ring is fixed to the yoke by the outer peripheral portion of the upper opening of the recess being caulked, and the revolving shaft that passes through the pedestal and is fitted to the inner ring of the bearing, The lower end is caulked or screwed while being positioned with respect to the upper surface of the pedestal by a flange or the like protruding radially outward, and an inner ring is formed between the caulked or screwed portion and the flange and the like. Characterized by holding and fixing the caster.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the caster of the present invention will be described in more detail. 1 to 6 are diagrams showing a time series of a manufacturing process of an embodiment of the caster 1 of the present invention, and FIG. 6 is a perspective view of a completed assembled state.

As shown in FIG. 6, a caster 1 according to this embodiment has a pedestal 2 attached to a body to be attached (a trolley body or the like), a yoke 3 provided to be pivotable with respect to the pedestal 2, and a yoke 3 3 bifurcated left and right support pieces 32,
32 and a wheel 4 rotatably held between them.

The pedestal 2 of this embodiment is formed in a substantially rectangular plate shape, and mounting holes 21, 21. This mounting hole 21
Is used when the caster 1 is attached to the attached body.

A yoke 3 attached to the lower surface of the pedestal 2
As shown in FIG. 1, is formed to be bent in a downward substantially U-shape opened downward. That is, the yoke 3 is formed integrally with the plate-like support pieces 32, 32 extending substantially vertically downward with respect to the center piece 31 at the left and right ends of the center piece 31 arranged in a substantially horizontal state.

The central piece 31 of the yoke 3 has a substantially cylindrical portion 3
1a is formed, and a substantially cylindrical concave portion 33 is formed in a central portion of the substantially cylindrical portion 31a so as to be recessed downward. At the center of the bottom wall 33a of the recess 33, a hole 33b having a diameter smaller than the inner diameter of the peripheral side wall of the recess 33 is formed so as to penetrate vertically.

The pedestal 2 and the yoke 3 of this embodiment
Are formed by press-forming steel plates, respectively.
For example, the yoke 3 is formed by bending a steel plate punched into a substantially boomerang shape into a substantially U-shape to form the left and right support pieces 32, 32.
Is formed integrally with a press-formed product in a shape in which the concave portion 33 is formed by drawing in the center of a central piece 31 connecting the left and right support pieces 32, 32.

As shown in FIGS. 1 and 2, the bearing 7 is fitted and accommodated in the recess 33 of the yoke 3. Bearing 7
In this embodiment, a substantially cylindrical inner ring 71 and an outer ring 72 are rotatable via rolling elements 73. In the present embodiment, a ball bearing, particularly a deep groove ball bearing is preferably used.

When the bearing 7 is accommodated in the recess 33 of the yoke 3, the lower end surface of the outer ring 72 of the bearing 7 abuts on a bottom wall 33a around the hole 33b at the bottom of the recess 33, as shown in FIG. Being held. When the bearing 7 is accommodated in the recess 33, the upper end surface of the bearing 7 is disposed so as to be slightly recessed below the upper opening of the recess 33.

Accordingly, the outer peripheral portion of the upper opening of the concave portion 33 can be caulked while the bearing 7 is housed in the concave portion 33 of the yoke 3. By caulking the outer periphery of the upper opening of the concave portion 33, as shown in FIG. 3, the inner diameter of the upper opening of the concave portion 33 is slightly narrowed, and the bearing 7 is provided between the bottom wall 33a of the concave portion 33 and the caulked portion 33c. , The bearing 7 can be integrally fixed to the yoke 3.

The yoke 3 holding the bearing 7 is attached to the pedestal 2 via the turning shaft 6. That is, first, as shown in FIG.
The pedestal 2 is arranged on the upper part of (31a) so as to overlap with each other, and through a hole 22 formed in the center of the pedestal 2,
The turning shaft 6 is inserted into the hole of the bearing 7 (the inner diameter of the inner ring 71). The pedestal 2 has a shape in which the periphery of the hole 22 is slightly recessed downward in a circular shape.
Is arranged in a state where the lower end surface of the inner ring 71 is in contact with the upper end surface of the inner ring 71 of the bearing 7.

Then, in that state, as shown in FIG.
The lower end of the pivot 6 is swaged. By the way, the turning shaft 6 of this embodiment has a head (flange) 61 projecting radially outward (outer peripheral side) at an upper end portion.
Is accommodated in the recess 23 of the pedestal 2 and attached. When the lower end of the pivot 6 is swaged, the head 6 of the pivot 6
1 and the inner ring 71 of the bearing 7
Is sandwiched through. Then, the inner ring 71 of the bearing 7 is fixed to the pedestal 2 via the turning shaft 6.
As a result, the yoke 3 becomes rotatable about the pivot 6 with respect to the pedestal 2 via the bearing 7.

The above operation can be performed with the center piece 31 of the yoke 3 facing downward and the left and right support pieces 32, 32 facing upward. In other words, if the turning shaft 6 is set up with its head 61 down, the bearing 7 of the yoke 3 is passed through the turning shaft 6 via the pedestal 2, and then the upper end of the turning shaft 6 is swaged. Good.

The left and right support pieces 32, 3 of the yoke 3
The wheel 4 is rotatably held by the axle 5 that is bridged over the lower end of the wheel 2. The wheels 4 may be attached to the axle 5 via bearings or may be attached without bearings.

The caster 1 constructed as described above
Is used by being attached to an object to be mounted by superimposing the pedestal 2 on the object to be mounted and screwing the same through a mounting hole 21 of the pedestal 2. As described above, the head 61 of the revolving shaft 6 is inserted into the recess 23 formed in the center of the pedestal 2.
Is stored, so that the caster 1 can be mounted in a state where the pedestal 2 is overlapped on the mounted body.

In the caster 1 of this embodiment, the bearing 7 can be directly attached to the yoke 3 itself without the intervention of a bearing case. Therefore, the number of parts can be reduced, the material and labor for manufacturing can be saved, and the cost can be reduced. Further, since it is not necessary to mount the bearing case on the yoke, the structure can be made compact by that much. In addition, the noise during use of the caster can be further reduced than before, and the present invention can be widely applied to loading of nighttime luggage to convenience stores, nursing care, medical care, and other uses.

FIG. 7 is a longitudinal sectional view showing a second embodiment of the caster 1 of the present invention, and shows a state before the wheels 4 are attached. Note that the caster 1 of this embodiment is also basically the same as that of the above-described embodiment, and therefore, a description will be given below mainly of the portions different from the above-described embodiment.

In this embodiment, the upper part of the turning shaft 6 is arranged so as to project upward from the upper surface of the pedestal 2, and the upwardly projecting part is a screw part 69. Therefore, when the caster 1 of this embodiment is mounted on the mounted body, the screw portion 69 of the turning shaft 6 can be screwed into the screw hole formed in the mounted body.

The pedestal 2 of this embodiment has a yoke central piece 31.
Is formed in a substantially disk shape having a diameter slightly larger than that of the substantially cylindrical portion 31a, and the outer peripheral portion 29 is slightly bent downward in an arc shape. Therefore, the pedestal 2 is arranged so as to cover the upper part of the substantially cylindrical portion 31a of the yoke center piece 31.

In the pedestal 2 of the embodiment, a recess 23 is formed by recessing the periphery of the turning shaft insertion hole 22 downward. Hole 22
Is formed in a flat plate shape without forming a recessed portion around the periphery. Instead, a washer 8 is interposed between the pedestal 2 and the inner ring 71 of the bearing 7 on the lower surface of the pedestal 2. In addition, as in the first embodiment, the pedestal 2 in which the concave portion 23 is formed can be used. In this case, the washer 8 can be omitted.

Also in this embodiment, after the bearing 7 is accommodated in the concave portion 33 formed in the yoke 3, the outer peripheral portion (33 c) of the concave portion 33 is caulked, so that the outer ring 72 is attached to the yoke 3.
Is fixed. After the turning shaft 6 is fitted to the bearing 7 via the pedestal 2 and the washer 8, the flange 6 of the turning shaft 6 is fitted.
1A and the caulked portion 62 at the lower end,
1 is held. As a result, the yoke 3 is attached to the pedestal 2 so as to be rotatable about the pivot 6.

The caster 1 of the present invention is not limited to the configuration of the above-described embodiment, but can be changed as appropriate. For example, in each of the above embodiments, an example in which the lower end portion of the turning shaft 8 is swaged to fix the bearing inner ring 71 to the turning shaft 8 has been described. However, as shown in FIG. The bearing inner ring 71 may be fixed to the turning shaft 8 by screwing the nut 67 into the formed screw portion 68. That is, in the embodiment of FIG.
The pivot 2 fitted to the pedestal 2 and the bearing inner ring 71 is formed in a bolt shape, and its head 61 is formed in the recessed portion 23 of the pedestal 2.
And the nut 6 screwed into the screw portion 68
The turning shaft 6 is fixed to the bearing inner ring 71 by tightening the 7 to press the lower end surface of the bearing inner ring 71 via the washer 66.

Further, in each of the above embodiments, the concave portion 33 formed in the central piece 31 of the yoke 3 is formed by press-forming by being recessed downward. However, the concave portion 33 may be formed by being recessed upward in some cases. . In that case, the concave portion 33 that opens downward
Therefore, after the bearing 7 is inserted into the concave portion 33, the concave portion 3
The outer peripheral portion of the lower opening 3 may be swaged.

[0032]

As described above, according to the caster of the present invention, the bearing can be fixed directly to the yoke itself. Therefore, a bearing case is unnecessary, the number of parts can be reduced, and the labor and cost for manufacturing can be reduced. In addition, a caster with higher silence can be obtained.

[Brief description of the drawings]

FIG. 1 is a view showing a manufacturing process of a caster according to an embodiment of the present invention, and is a perspective view showing a state in which a bearing is housed in a concave portion of a yoke.

FIG. 2 is a longitudinal sectional view showing a state in which a bearing is accommodated in a concave portion of a yoke, which is a view showing a continuation of a production process of the caster of FIG. 1;

FIG. 3 is a longitudinal sectional view showing a state where the outer ring of the bearing is fixed to the yoke by caulking the outer peripheral portion of the upper opening of the concave portion of the yoke by FIG.

FIG. 4 is a longitudinal sectional view showing a state in which a turning shaft is inserted into a bearing attached to a yoke via a pedestal to a bearing attached to a yoke, which is a view showing a continuation of a production process of the caster of FIG.

5 is a view showing a continuation of the production process of the caster shown in FIG. 4, and is a longitudinal sectional view showing a state in which the lower end of the turning shaft is caulked and the yoke is attached to the pedestal.

FIG. 6 is a perspective view showing a continuation of the production process of the caster shown in FIG. 5, showing a state in which the wheels are attached to the yoke in an assembled state.

FIG. 7 is a longitudinal sectional view showing a second embodiment of the caster of the present invention, in which wheels are omitted.

FIG. 8 is a longitudinal sectional view showing a third embodiment of the caster of the present invention, in which wheels are omitted.

FIG. 9 is a longitudinal sectional view showing a conventional caster, in which wheels are omitted.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Caster 2 Pedestal 3 Yoke 4 Wheel 6 Revolving shaft 7 Bearing 31 Central piece 32 Support piece 33 Depressed part 33c Caulking part 61, 61A Flange part 71 Inner ring 72 Outer ring

Claims (3)

[Claims] A bearing is accommodated in a recess formed in a yoke of a press-formed product, an outer peripheral portion of the recess is caulked, an outer ring of the bearing is attached to the yoke, and a turning shaft is attached to an inner ring of the bearing. A caster, wherein the yoke is rotatable about the pivot about the pedestal. 2. A press in which a substantially cylindrical concave portion is integrally formed in a central piece connecting the upper ends of left and right support pieces formed by forked downward and forked. A molded product yoke, a wheel rotatably held between left and right support pieces of the yoke, and a wheel housed in the recess of the yoke, an outer peripheral portion of the recess being caulked, and an outer ring fixed to the yoke. A caster, comprising: a bearing; and a pedestal to which the yoke is rotatably mounted via a turning shaft fixed to an inner ring of the bearing. 3. A caster comprising a pedestal, a yoke rotatably mounted on the pedestal about a pivot axis, and a wheel rotatably mounted on the yoke, wherein the yoke is formed by pressing a steel plate. The upper central piece is formed by recessing a substantially cylindrical recess for accommodating the bearing downward, and the bearing disposed in the recess is caulked at the outer periphery of the upper opening of the recess. With this, the outer ring is fixed to the yoke, and the rotating shaft that penetrates the pedestal and is fitted to the inner ring of the bearing is caulked at the lower end while being positioned with respect to the upper surface of the pedestal by a flange or the like protruding radially outward. Or screwed, etc.
A caster characterized in that the inner ring is held and fixed between the caulked portion or the screwed portion and the flange portion and the like.