Single-wheel hollow caster

Abstract

Provided is a single-wheel hollow caster having a configuration that is easy to assemble and can reduce costs. 【Solution means】 The single-wheel hollow caster 1 includes a substantially cylindrical main body 13, a wheel 15 disposed around the main body 13, a cylindrical sliding ring 11P disposed between the main body 13 and the wheel 15, a groove portion G provided on one of the outer periphery of the main body 13 and the inner periphery of the wheel 15 for slidably accommodating the sliding ring 11P, and a rail portion R provided on the other of the outer periphery of the main body 13 and the inner periphery of the wheel 15 for slidably supporting the surface of the sliding ring 11P on the side opposite to the groove portion. Therefore, the space surrounded by the rail portion R and the groove portion G is used as an accommodation chamber C for the sliding ring 11P, and a bearing function can be imparted to the portion composed of the accommodation chamber C and the sliding ring 11P. As a result, the number of parts can be reduced.

Description

Technical Field

[0001] The present invention relates to casters attached to the bottom side of shopping carts, trolleys, wagons, tables, chairs, cabinets, shelves, etc. used in facilities such as shopping malls, supermarkets, airports, vehicles such as wheelchairs and baby carriages, and other heavy objects, and particularly to single-wheel hollow casters that are single-wheel and hollow.

Background Art

[0002] For example, FIGS. 1 to 3 of Patent Document 1 disclose a hollow caster in which a ring-shaped holder 3 is attached to a ring-shaped main body 1 and a wheel 2 is attached to the holder 3. In this hollow caster, dry bearings 5 are sandwiched between the holder 3 and the wheel 2, and between the main body 1 and the wheel 2, respectively. Since light can pass through the hollow portion of this hollow caster and the appearance can be made lighter, it is particularly suitable for carts and furniture that emphasize design.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, the hollow caster described in FIGS. 1 to 3 of Patent Document 1 has a problem that the number of parts is large, such as requiring at least two dry bearings, resulting in high cost and complicated assembly.

[0005] Therefore, an object of the present invention is to provide a single-wheel hollow caster having a configuration that is easy to assemble and can suppress costs.

Means for Solving the Problems

[0006] In order to solve the above problems, one single-wheel hollow caster according to the present invention includes a substantially cylindrical main body, a wheel disposed around the main body, a cylindrical sliding ring disposed between the main body and the wheel, a groove portion provided on one of the outer periphery of the main body and the inner periphery of the wheel for slidably accommodating the sliding ring, and a rail portion provided on the other of the outer periphery of the main body and the inner periphery of the wheel for slidably sandwiching the sliding ring and engaging with the groove portion.

[0007] In any single-wheel hollow caster according to the present invention for solving the above problems, a taper may be provided on either one of the side surface of the groove portion and the side surface of the rail portion so that the side surface of the groove portion and the side surface of the rail portion do not come into surface contact.

[0008] In any single-wheel hollow caster according to the present invention for solving the above problems, an air gap may be provided between the outer periphery of the main body and the inner periphery of the wheel so that the main body and the wheel do not come into surface contact.

[0009] In any single-wheel hollow caster according to the present invention for solving the above problems, the main body is composed of a left main body and a right main body that can be fitted to each other, and the joint pattern of the left main body and the right main body may be selected so as to deviate from the inner periphery or the outer periphery of the sliding ring.

[0010] In any single-wheel hollow caster according to the present invention for solving the above problems, the wheel may include an inner wheel located on the side of the sliding ring and an outer wheel attached around the inner wheel.

[0011] In any single-wheel hollow caster according to the present invention for solving the above problems, the sliding ring is made of stainless steel, and at least the portion of the wheel and the main body that contacts the sliding ring may be made of synthetic resin.

[0012] In any single-wheel hollow caster according to the present invention for solving the above problems, the synthetic resin is PA6GF30(Polyamide It may be 6 glass fibers (30%).

Advantages of the Invention

[0013] The single-wheel hollow caster according to the present invention includes a substantially cylindrical main body, wheels disposed around the main body, a cylindrical sliding ring disposed between the main body and the wheels, a groove portion provided on one of the outer periphery of the main body and the inner periphery of the wheels for slidably accommodating the sliding ring, and a rail portion provided on the other of the outer periphery of the main body and the inner periphery of the wheels for slidably sandwiching the sliding ring and engaging with the groove portion. Therefore, the space surrounded by the rail portion and the groove portion can be used as an accommodation chamber for the sliding ring, and a bearing function can be imparted to the portion composed of the accommodation chamber and the sliding ring. Accordingly, there is no need for a component such as a ready-made bearing, the number of components can be minimized, and an easy-to-assemble and cost-reducing single-wheel hollow caster with such a configuration can be realized.

Brief Description of the Drawings

[0014]

Figure 1

Figure 2

Figure 3

Figure 4

Embodiments for Carrying Out the Invention

[0015] Hereinafter, a preferred embodiment of the single-wheel hollow caster according to the present invention will be described with reference to the drawings. The single-wheel hollow caster according to the present embodiment is, for example, a caster for a wagon or a cart. However, it is also possible to use the single-wheel hollow caster of the present embodiment as a caster for moving a heavy object other than a wagon or a cart.

[0016] FIG. 1 is a perspective view of a single-wheel hollow caster according to this embodiment, and FIG. 2 is an exploded view of the single-wheel hollow caster. As shown in FIG. 2, the single-wheel hollow caster 1 of this embodiment has an internally asymmetrical left-right structure, but it is also possible to have a structure with left-right inversion.

[0017] As shown in FIG. 1, the single-wheel hollow caster 1 according to this embodiment includes a substantially cylindrical main body 13 and a wheel 15 disposed around the main body 13. Among these, the main body 13 is composed of a left main body 13L and a right main body 13R that can be fitted to each other, as shown in FIG. 2. On the right side of the left main body 13L, a substantially cylindrical fitting portion 13B protrudes. This fitting portion 13B fits into a substantially cylindrical fitted portion 13E that protrudes from the left side of the right main body 13R. Also, at a position outside the hollow portion 13A of the left main body 13L, a bearing portion 13C made of the same member as the left main body 13L is provided. At the corresponding position of the right main body 13R, a fitted portion 13D that fits into the proximal end side (arm portion) of the bearing portion 13C of the left main body 13L is provided as the same member as the right main body 13R. Further, a shaft 11 is fitted into the bearing portion 13C from the top side, and the fitting portion between the shaft 11 and the bearing portion 13C is covered by a cover 12. And between the main body 13 and the wheel 15, as shown in FIG. 2, a cylindrical sliding ring 11P is disposed. The wheel 15 is composed of an inner ring 15in located on the side of the sliding ring 11P and an outer ring 15out attached around the inner ring 15in.

[0018] FIG. 3(A) is a plan view of the single-wheel hollow caster, FIG. 3(B) is a right side view, FIG. 3(C) is a cross-sectional view taken along line A-A of FIG. 3(B), and FIG. 4 is an enlarged view of the circular frame C in FIG. 3(C). As shown in FIGS. 3 and 4, the single-wheel hollow caster 1 of this embodiment includes a groove portion G provided on the outer periphery of the main body 13 for slidably accommodating the sliding ring 11P, and a rail portion R provided on the inner periphery of the wheel 15 for engaging with the groove portion G while slidably sandwiching the sliding ring 11P. These groove portion G and rail portion R form an accommodation chamber C for the sliding ring 11P between the wheel 15 and the main body 13. In the single-wheel hollow caster 1 of this embodiment, the portion composed of this accommodation chamber C and the sliding ring 11P functions as a bearing.

[0019] Here, while the portions of the side surface of the groove portion G near the rail portion R are provided with the tapers T, T, the side surface of the rail portion R is not provided with a taper and the side surface is upright. Therefore, although the corners (edges) of the rail portion R abut against the tapers T, T, the rail portion R does not fit perfectly into the groove portion G, so the contact between the side surface of the groove portion G and the side surface of the rail portion R is "line contact" rather than "surface contact". The portions indicated by reference numerals C1, C1 in FIG. 4 are the contact portions between the groove portion G and the rail portion R. Also, air gaps G1, G1 are provided between the outer periphery of the main body 13 and the inner periphery of the wheel 15 (on the side of the accommodation chamber C) so that the main body 13 and the wheel 15 do not come into surface contact. Therefore, in the single-wheel hollow caster 1 of the present embodiment, a sliding ring 11P can always be interposed between the main body 13 and the wheel 15 to avoid the main body 13 and the wheel 15 coming into surface contact. According to such tapers T, T and air gaps G1, G1, it is possible to prevent the main body 13 and the wheel 15 from coming into contact with each other and causing wear.

[0020] Also, the pattern of the joint S between the left main body 13L and the right main body 13R (the fitting portion between the fitting portion 13B and the fitted portion 13E in FIG. 2) is appropriately selected so as to deviate from the inner periphery 11P-1 and the outer periphery 11P-2 of the sliding ring 11P as shown in FIG. 4. For example, only one of the left main body 13L and the right main body 13R (only the right main body 13R in the illustrated example) comes into surface contact with the inner periphery 11P-1 of the sliding ring 11P, and the other (the left main body 13L in the illustrated example) does not come into surface contact with the inner periphery 11P-1 of the sliding ring 11P. Therefore, it is possible to prevent a situation in which any portion of the joint S between the left main body 13L and the right main body 13R comes into contact with the inner periphery 11P-1 or the outer periphery 11P-2 of the sliding ring 11P and the sliding (slidability) of the aforementioned bearing deteriorates.

[0021] Also, in the above single-wheel hollow caster 1, the sliding ring 11P is made of stainless steel, and at least the portions of the wheel 15 and the main body 13 that contact the sliding ring 11P are made of synthetic resin. As this synthetic resin, in particular, PA6GF30 ( Polyamide6 glass fibers (30%) is suitable. By appropriately selecting the material in this way, the slidability between the sliding ring 11P and the wheel 15 and the slidability between the sliding ring 11P and the main body 13 can be enhanced respectively.

[0022] In the above single-wheel hollow caster 1, the material of the shaft 11 is a metal such as iron, for example, the material of the cover 12 is a synthetic resin such as PA6 (6 nylon resin), and the materials of the left main body 13L and the right main body 13R are, for example, PA6GF30( Polyamide 6 glass fibers 30%) and other synthetic resins with both wear resistance and strength. The material of the sliding ring 11P is stainless steel such as SUS304. The material of the inner ring 15in is a synthetic resin such as PA6 (6 nylon resin), for example, and the material of the outer ring 15out is a synthetic resin with appropriate grip properties such as TPU (thermoplastic polyurethane elastomer). Note that these materials are not limited to this, and appropriate materials can be adopted according to the functions of each member.

[0023] As described above, the single-wheel hollow caster 1 according to the present embodiment includes a substantially cylindrical main body 13, a wheel 15 disposed around the main body 13, a cylindrical sliding ring 11P disposed between the main body 13 and the wheel 15, a groove portion G provided on one of the outer periphery of the main body 13 and the inner periphery of the wheel 15 for slidably accommodating the sliding ring 11P, and a rail portion R provided on the other of the outer periphery of the main body 13 and the inner periphery of the wheel 15 for engaging with the groove portion G while slidably sandwiching the sliding ring 11P. Therefore, the space surrounded by the rail portion R and the groove portion G is used as the accommodation chamber C of the sliding ring 11P, and the function of a bearing can be imparted to the portion composed of the accommodation chamber C and the sliding ring 11P. Therefore, according to the single-wheel hollow caster 1 of the present embodiment, it is not necessary to use a component such as a ready-made bearing, and the number of components can be minimized, so that the assembly is easy and inexpensive.

[0024] In the above-described embodiment, the groove portion G is formed on the main body 13 side and the rail portion R is formed on the wheel 15 side. However, the groove portion G may be formed on the wheel 15 side and the rail portion R may be formed on the main body 13 side.

[0025] In addition, in the above-described embodiment, in order to avoid the groove portion G and the rail portion R from being in surface contact, the tapered portions T, T are provided on the groove portion G side, but the tapered portions T, T may be provided on the rail portion R side.

[0026] Also, in the above-described embodiment, for example, at least one of the diameter size and the width size of the wheel 15, or the ratio of the diameter size to the width size, etc. can be changed according to the use of the caster or the like.

[0027] Note that the present invention is not limited to the above-described embodiment, and the components can be appropriately deformed and embodied without departing from the gist thereof. Also, various inventions can be formed by appropriately combining a plurality of components disclosed in each embodiment.

Explanation of Reference Numerals

[0028] 1 Single-wheel hollow caster 11 Shaft 12 Cover 13 Body 13A Hollow portion 13B Fitting portion 13E Fitted portion 11P Sliding ring 15 Wheel 15out Outer ring 15in Inner ring G Groove portion G1 Air gap S Joint C Accommodation chamber C1 Contact location

Claims

1. A substantially cylindrical main body; Wheels disposed around the body; a sliding ring disposed between the main body and the wheel, the sliding ring being made of only a single cylinder having an inner peripheral surface and an outer peripheral surface that are in surface contact with the main body and the wheel; A single-wheel hollow caster comprising: a groove portion provided on an outer periphery of the main body and configured to slidably accommodate the sliding ring; a rail portion provided on an inner periphery of the wheel and engaging with the groove portion while slidably holding the sliding ring therebetween; A space having a rectangular cross section surrounded only by the groove portion and the rail portion which are engaged with each other constitutes an accommodation chamber for the single sliding ring, and a combination of the single sliding ring and the accommodation chamber functions as the only bearing of the single-wheel hollow caster, The main body is composed of a left main body and a right main body that can be fitted together, and the joint pattern of the left main body and the right main body is selected at a corner of the accommodation chamber so as to be out of the inner peripheral surface, the outer peripheral surface and both side surfaces of the sliding ring, so that one of the left main body and the right main body constitutes two sliding surfaces that slide on one side surface and the inner peripheral surface of the sliding ring, and the other of the left main body and the right main body constitutes one sliding surface that slides on the other side surface of the sliding ring. A single-wheel hollow caster characterized by:

2. The single-wheel hollow caster according to claim 1, Either the side surface of the groove portion or the side surface of the rail portion is tapered so that the side surface of the groove portion and the side surface of the rail portion do not come into surface contact with each other. A single-wheel hollow caster characterized by:

3. The single-wheel hollow caster according to claim 1, An air gap is provided between the outer periphery of the body and the inner periphery of the wheel so that the body and the wheel do not come into surface contact with each other. A single-wheel hollow caster characterized by:

4. The single-wheel hollow caster according to claim 1, The wheel is An inner ring located on the sliding ring side; an outer ring attached around the inner ring; A single-wheel hollow caster comprising:

5. The single-wheel hollow caster according to claim 1, The sliding ring is made of stainless steel, At least the portion of the wheel and the main body that comes into contact with the sliding ring is made of synthetic resin. A single-wheel hollow caster characterized by:

6. The single-wheel hollow caster according to claim 5, The synthetic resin is PA6GF30 (polyamide 6 glass fiber 30%) A single-wheel hollow caster characterized by:

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