Single-wheel hollow caster

Abstract

To provide a single wheel hollow caster easy to assemble and capable of suppressing the cost.SOLUTION: 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 an outer periphery of the main body 13 and an inner periphery of the wheel 15 and 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 and slidably supporting a surface of the sliding ring 11P on a side opposite to the groove portion. A space surrounded by the rail part R and the groove part G is used as a storage chamber C of the sliding ring 11P part, and a bearing function can be imparted to a part composed of the storage chamber C and the sliding ring 11P part, and as a result, the number of part items can be restrained.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a caster that can be attached to the bottom of heavy objects such as push carts, hand trucks, wagons, furniture such as tables, chairs, dressers, and shelves, vehicles such as wheelchairs and strollers, and other heavy objects used in facilities such as shopping malls, supermarkets, and airports, and in particular to a single-wheel hollow caster. [Background technology]

[0002] For example, Figures 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. This hollow caster allows light to pass through the hollow portion, giving it a light appearance, making it particularly suitable for carts and furniture where design is important. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-251653 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the hollow caster shown in FIGS. 1 to 3 of Patent Document 1 has a large number of parts, such as at least two dry bearings, and therefore has problems of high cost and complicated assembly.

[0005] SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a single-wheel hollow caster that is easy to assemble and can reduce costs. [Means for solving the problem]

[0006] In order to solve the above problems, one single-wheel hollow caster of the present invention is characterized by comprising an approximately cylindrical body, wheels arranged around the body, a cylindrical sliding ring arranged between the body and the wheels, a groove portion provided on one of the outer periphery of the body and the inner periphery of the wheels, which slidably accommodates the sliding ring, and a rail portion provided on the other of the outer periphery of the body and the inner periphery of the wheels, which engages with the groove portion while slidably clamping the sliding ring.

[0007] In order to solve the above problem, in any of the single-wheel hollow casters of the present invention, either the side surface of the groove portion or the side surface of the rail portion may be tapered so that there is no surface contact between the side surface of the groove portion and the side surface of the rail portion.

[0008] In order to solve the above problem, in any of the single-wheel hollow casters according to the present invention, an air gap may be 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.

[0009] In order to solve the above problem, in any of the single-wheel hollow casters according to the present invention, the main body is composed of a left main body and a right main body that can be fitted together, and the pattern of the joint between the left main body and the right main body may be selected so as to deviate from the inner or outer circumference of the sliding ring.

[0010] In order to solve the above problem, in any of the single-wheel hollow casters according to the present invention, the wheel may include an inner ring located on the side of the sliding ring, and an outer ring attached to the periphery of the inner ring.

[0011] In order to solve the above problem, in any of the single-wheel hollow casters according to the present invention, the sliding ring may be made of stainless steel, and at least the parts of the wheel and the main body that come into contact with the sliding ring may be made of synthetic resin.

[0012] In any one of the single-wheel hollow casters according to the present invention, in order to solve the above-mentioned problems, the synthetic resin may be PA6GF30 (polyamide 6 glass fiber 30%). [Effects of the Invention]

[0013] The single-wheel hollow caster according to the present invention comprises a substantially cylindrical body, wheels disposed around the body, a cylindrical sliding ring disposed between the body and the wheels, a groove provided on one of the outer periphery of the body or the inner periphery of the wheels for slidably accommodating the sliding ring, and a rail provided on the other of the outer periphery of the body or the inner periphery of the wheels for engaging with the groove while slidably sandwiching the sliding ring. Therefore, the space enclosed by the rail and the groove serves as a chamber for accommodating the sliding ring, and the chamber and the sliding ring can be given bearing functionality. Therefore, there is no need for a ready-made bearing, and the number of parts can be minimized, resulting in a single-wheel hollow caster that is easy to assemble and allows costs to be kept low. [Brief explanation of the drawings]

[0014] [Figure 1] FIG. 1 is a perspective view of a single-wheel hollow caster according to this embodiment. [Figure 2] Figure 2 is an exploded view of a single hollow caster. [Figure 3] FIG. 3(A) is a plan view of the single-wheel hollow caster, FIG. 3(B) is a right side view, and FIG. 3(C) is a cross-sectional view taken along line AA of FIG. 3(B). [Figure 4] FIG. 4 is an enlarged view of the circle C in FIG. 3(C). DETAILED DESCRIPTION OF THE INVENTION

[0015] A preferred embodiment of a single-wheel hollow caster according to the present invention will be described below with reference to the drawings. The single-wheel hollow caster according to this embodiment is a caster for, for example, a wagon or cart. However, the single-wheel hollow caster according to this embodiment can also be used as a caster for moving heavy objects other than wagons or carts.

[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 according to this embodiment has an asymmetric internal structure, but it is also possible to make it have a reversed structure.

[0017] As shown in FIG. 1, the single-wheel hollow caster 1 according to this embodiment includes a substantially cylindrical main body 13 and wheels 15 arranged around the main body 13. As shown in FIG. 2, the main body 13 is composed of a left main body 13L and a right main body 13R that can fit together. A substantially cylindrical fitting portion 13B protrudes from the right side of the left main body 13L, and this fitting portion 13B fits into a substantially cylindrical fitted portion 13E protruding from the left side of the right main body 13R. A bearing portion 13C made of the same material as the left main body 13L is provided at a position outside the hollow portion 13A of the left main body 13L, and a fitted portion 13D made of the same material as the right main body 13R is provided at a corresponding position on the right main body 13R. The fitted portion 13D fits into the base end (arm portion) of the bearing portion 13C of the left main body 13L. Furthermore, shaft 11 is fitted into bearing portion 13C from the top side thereof, and the fitting portion between shaft 11 and bearing portion 13C is covered with cover 12. As shown in Fig. 2, a cylindrical sliding ring 11P is disposed between main body 13 and wheel 15, and wheel 15 is composed of an inner ring 15in located on the sliding ring 11P side and an outer ring 15out attached to the periphery of 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 AA 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 is provided with a groove portion G on the outer periphery of the main body 13 that slidably houses the sliding ring 11P, and a rail portion R on the inner periphery of the wheel 15 that engages with the groove portion G while slidably sandwiching the sliding ring 11P, and 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 consisting of this accommodation chamber C and the sliding ring 11P functions as a bearing.

[0019] Here, the side of the groove G is tapered at a portion closer to the rail portion R, while the side of the rail portion R is not tapered and is upright. Therefore, although the corners (edges) of the rail portion R abut against the tapers T, T, the rail portion R does not completely fit into the groove G, and therefore the contact between the side of the groove G and the side of the rail portion R is "line contact" rather than "surface contact." The locations indicated by symbols C1, C1 in FIG. 4 are the contact points between the groove G and the rail portion R. Furthermore, air gaps G1, G1 are provided between the outer periphery of the main body 13 and the inner periphery of the wheel 15 (to the side of the storage chamber C) to prevent surface contact between the main body 13 and the wheel 15. Therefore, in the single-wheel hollow caster 1 of this embodiment, a sliding ring 11P is always interposed between the main body 13 and the wheel 15, thereby preventing surface contact between the main body 13 and the wheel 15. Such tapers T, T and air gaps G1, G1 can prevent the main body 13 and the wheel 15 from coming into contact with each other and causing wear.

[0020] Furthermore, the pattern of the joint S between the left main body 13L and the right main body 13R (the joint between the mating portion 13B and the mated portion 13E in FIG. 2) is appropriately selected so as to deviate from the inner periphery 11P-1 and 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. This prevents any part of the joint S between the left main body 13L and the right main body 13R from coming into contact with the inner periphery 11P-1 or the outer periphery 11P-2 of the sliding ring 11P, thereby preventing the aforementioned problem of the bearing slippage (slidability) from deteriorating.

[0021] In the single-wheel hollow caster 1 described above, the sliding ring 11P is made of stainless steel, and at least the portions of the wheel 15 and the main body 13 that come into contact with the sliding ring 11P are made of synthetic resin. PA6GF30 (polyamide 6, glass fiber 30%) is particularly suitable as this synthetic resin. By selecting the appropriate material in this way, it is possible to improve the sliding properties between the sliding ring 11P and the wheel 15, and between the sliding ring 11P and the main body 13.

[0022] In the single-wheel hollow caster 1 described above, the shaft 11 is made of a metal such as iron, the cover 12 is made of a synthetic resin such as PA6 (6 nylon resin), the left body 13L and the right body 13R are made of a synthetic resin that is both wear-resistant and strong such as PA6GF30 (polyamide 6 glass fiber 30%), the sliding ring 11P is made of stainless steel such as SUS304, the inner ring 15in is made of a synthetic resin such as PA6 (6 nylon resin), and the outer ring 15out is made of a synthetic resin with adequate grip such as TPU (thermoplastic polyurethane elastomer). However, these materials are not limited to these, and appropriate materials can be used depending on the function of each component.

[0023] As described above, the single-wheel hollow caster 1 according to this embodiment includes a substantially cylindrical main body 13, wheels 15 arranged around the main body 13, a cylindrical sliding ring 11P arranged between the main body 13 and wheels 15, a groove G provided on one of the outer periphery of the main body 13 or the inner periphery of the wheels 15 and slidably housing the sliding ring 11P, and a rail R provided on the other of the outer periphery of the main body 13 or the inner periphery of the wheels 15 and engaging with the groove G while slidably sandwiching the sliding ring 11P. Therefore, the space enclosed by the rail R and the groove G serves as a housing chamber C for the sliding ring 11P, and the portion consisting of the housing chamber C and the sliding ring 11P can be given the function of a bearing. Therefore, the single-wheel hollow caster 1 of this embodiment does not require a ready-made bearing part and can minimize the number of parts, making assembly easy and inexpensive.

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

[0025] In addition, in the above-described embodiment, the tapers T, T are provided on the groove G side to prevent surface contact between the groove G and the rail R, but the tapers T, T may also be provided on the rail R side.

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

[0027] The present invention is not limited to the above-described embodiments, and various modifications and variations of the components can be made without departing from the spirit of the present invention. Furthermore, various inventions can be created by appropriately combining the multiple components disclosed in each embodiment. [Explanation of symbols]

[0028] 1 Single hollow caster 11 axes 12 Cover 13 Main unit 13A Hollow part 13B Mating part 13E Mated part 11P sliding ring 15 wheels 15out outer ring 15in inner ring G groove G1 Air Gap S joint C Containment Room C1 Contact point

Claims

1. A substantially cylindrical main body; wheels disposed around the body; a cylindrical sliding ring disposed between the 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, the groove portion slidably accommodating the sliding ring; a rail portion provided on the other of the outer periphery of the main body and the inner periphery of the wheel, the rail portion engaging with the groove portion while slidably holding the sliding ring; A single-wheel hollow caster comprising:

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 body includes: The device is comprised of a left body and a right body that can be fitted together, and the seam pattern of the left body and the right body is selected so as to deviate from the inner or outer circumference of the sliding ring. A single-wheel hollow caster characterized by the following features.

5. 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 to the periphery of the inner ring; A single-wheel hollow caster comprising:

6. 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:

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

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