JP3272861B2 - Two-wheel casters made of synthetic resin - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a two-wheel caster, and more particularly to a two-wheel caster entirely made of synthetic resin and suitable for recycling.

[0002]

2. Description of the Related Art Conventionally, twin-wheel casters are usually
It consists of a wheel and a holder (or body) that holds the wheel and is attached to a leg of a chair or other furniture or office equipment, and the wheel is usually assembled to the holder by a metal axle. Wheels and holders are usually made of thermoplastic resin, so they can be recycled theoretically by crushing them when they are discarded, but they actually contain a metal axle of a different kind. In reality, it cannot be easily dismantled and is often simply discarded as it is. For this reason, with the spread of resin-made two-wheel casters, at present, pollution problems such as environmental pollution are occurring.

[0003]

SUMMARY OF THE INVENTION In order to solve such problems, the present invention provides a two-wheel caster made of synthetic resin which facilitates recycling so as to promote environmental protection and resource saving. The task was to do.

[0004]

SUMMARY OF THE INVENTION Therefore, according to the present invention, the axles of the two-wheel casters are no longer made of metal, and the axles are made of the same thermoplastic resin material as the caster body and the wheels, or a group of thermoplastic resins of the same type. Are manufactured integrally with the main body or as a separate type of fitting. In consideration of later recycling, it is most preferable that the entire body, wheels, and axle are made of the same thermoplastic resin material. However, even if different monomer compositions of the same thermoplastic resin group are used, for example, polyamide resins 6 and 66 are used. Any combination of materials that does not cause problems in molding or performance even when mixed when recycled later, such as a combination of the above, is well suited for the purpose of the present invention. Such combinable materials are referred to in the present invention as "homogeneous" materials.

Specifically, the present invention has a hollow bulge
A main body and an axle fitted into the hollow interior of the hollow expanded portion
And assembled to the axle in a rotatable and retaining state
Wheels provided, the main body, the axle and the wheels
Made of the same or the same kind of thermoplastic synthetic resin material separately
And, in the hollow interior of the hollow expanding portion of the main body, the
Annular protrusion for preventing axles from slipping, and its annular protrusion
Forms a protrusion to prevent rotation of the axle, extending in the axial direction
The axle has an annular protrusion for preventing the axle from falling off.
Engageable annular groove, and protrusion for stopping the axle rotation
And a recessed groove engageable with the hollow expanded portion of the main body.
By press-fitting the axle, the axle
An annular protrusion and an annular concave groove are engaged with each other to prevent the axle from rotating.
Of the main body and the concave groove are engaged with each other,
Synthetic resin twin wheels with a fixed axle
Casters . In this case, various means as shown in FIGS. 1, 2 and 3 will be taken later on how to fix the wheel to the resin axle . According to the present invention,
The axle is not made of metal like the conventional two-wheel caster made of resin , and the main body, axle and wheels are made of the same or similar thermoplastic composite
Since it is manufactured separately from a resin material, it is extremely easy to recycle and has the advantage that it can overcome pollution problems such as environmental pollution and environmental destruction caused by discarded two-wheel casters.

[0006]

An embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a front view showing a first embodiment according to the present invention in a partial cross section. The twin wheel caster of this embodiment is of a type in which a main body (holder) 1 has an integral axle 5. More specifically, the main body 1 integrally has a central supporting wall 3 inside a fender 2 having an arc shape. The supporting wall 3 has a semicircle or more contour when viewed from the side, and has an integrated axle 5 protruding from both sides thereof at the center thereof via an enlarged portion 4. The axle 5 is formed integrally with the same or similar resin material as the main body 1. An annular groove 6 is formed near the tip of the integral axle 5. The wheel 8 has a shape known per se, and a convex portion 10 is formed on the inner periphery of the central boss portion 9.
0 fits into the annular groove 6 to combine the wheels 8 so that they can rotate relative to each other, but in a locked state. 7 is a mounting shaft A for mounting the caster to a chair or other furniture leg.
This is also a well-known shape.

The caster shown in FIG. 1 differs from the prior art in that the axle 5 is not made of metal, but is integrally formed on the central support wall 3 with the same or similar material as the main body. This eliminates the need for shaft insert work, speeds up the process, and, when discarding used casters, removes the mounting shaft A, then simultaneously destroys and crushes the entire product and recycles it. be able to. For this reason, the caster of the present invention, unlike the conventional caster having a metal shaft and being discarded and causing environmental pollution, can contribute to environmental conservation and is also suitable for saving resources, meeting the demands of the times. It fits well.

The embodiment of the caster of the integral axle type shown in FIG. 1 can be a modified example as shown in FIG. In this example, the enlarged portion 4 and the axle 5A are formed integrally with the central support wall 3, and the axle 5A has an inner hole 5b. Correspondingly, the wheel 8A has an opening in the center, into which the stopper plug 8a is inserted, and the shaft portion 8b of the stopper plug 8a is
b is fixed by welding or bonding to prevent the wheel 8A from coming off. The wheel 8A relatively rotates with respect to the axle 5A and the stopper plug 8a. In this modified example as well, as in the previous example, the whole is molded from the same or the same type of resin material, so that when it is discarded, recycling can be facilitated and environmental pollution can be prevented.

FIG. 3 is an enlarged partial cross-sectional view showing still another modification. The main body, the fender portion, and the central support wall are the same as those shown in FIG. 2, and an annular groove 5c is formed in an inner hole 5b of an axle 5A molded integrally with the central support wall. Correspondingly, the stopper plug 8a fitted to the wheel (same as 8A in FIG. 2) has a projection 8c formed on the shaft. When the stopper plug 8a is inserted into the central opening of the wheel 8A and the shaft 8b is pushed into the inner hole 5b of the integrated axle 5A, the groove 5c and the protrusion 8c are fitted to prevent the wheel from coming off. The rotation of the wheel relative to the axle 5A and the stopper plug 8a is the same as in the case of FIG.

The concept of the all-resin caster according to the present invention can also be implemented in a second embodiment shown in FIG. 4, that is, in a form in which the main body and the axle are manufactured separately. The main body 21 of the caster in FIG. 4 has a hollow support 24 integrally formed with a fender 22 and a hollow support 24 formed integrally therewith. Enormous part 2
An annular protrusion 25 is formed in the hollow inside of 4 to prevent the axle from coming off. Intersecting with this, a protrusion 26 for preventing rotation is formed at the same time in the axial direction. The separate axle 28 has an annular groove 29 at a substantially central portion of the length, and a groove 30 is formed in a direction intersecting the annular groove 29. The concave groove 30 engages with the anti-rotation protrusion 26 on the inner surface of the enlarged portion to prevent the axle from rotating and also functions as a grease reservoir. 31 which is on the extension of the concave groove 30 also functions as a grease pool inside the wheel. The grease reservoirs 30 and 31 may be formed so as to face each other in the radial direction of the axle. In the vicinity of both ends of the axle 28, an annular concave groove 3 fitted with the convex portion 10 on the inner surface of the boss portion of the wheel (similar to the wheel 8 shown in FIG. 1 and omitted in FIG. 4).
2 are formed. In the embodiment of FIG. 4, the caster body 21 and the axle 28 can be molded from the same or the same kind of resin material having different strengths.
Is press-fitted into the enlarged portion 24 to prevent the rotation preventing protrusion 26 and the concave groove 3.
Assembling is performed by fitting the “0”. As described above, the wheels may be press-fitted into both ends of the axle 28 in the same manner as shown in FIG. 1 so as to be rotatable relative to the axle. Also in this embodiment, since the whole is made of the same or the same kind of resin material, when discarded, it can be easily crushed as it is and recycled.

[0011]

[0012]

As described above, according to the present invention, the axles are not made of metal as in the conventional two-wheel caster made of synthetic resin, and all of the main body, the axle and the wheels are made of essentially the same or similar thermoplastic material. Since it is made of synthetic resin, the casters to be discarded can be recycled very easily through a simple procedure, such as crushing, etc., and metal parts are included as before.
Pollution problems such as environmental destruction can be resolved,
There is an effect that the economic effect by saving resources can be achieved.

[Brief description of the drawings]

FIG. 1 is a partially sectional front view showing a first embodiment of a synthetic resin twin wheel caster according to the present invention.

FIG. 2 is a partial sectional view showing a modification of the embodiment shown in FIG.

FIG. 3 is an enlarged partial cross-sectional view showing still another modified example of the example shown in FIG. 2;

FIG. 4 is an exploded partial cross-sectional view (wheels omitted) showing a second embodiment of the synthetic resin twin wheel caster according to the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Main body (or holder) 2 ... Fender 3 ... Central support wall 4 ... Expanding part 5, 5A ... Axle 5b ... Inner hole 5c ... Annular concave groove 6 ... Annular concave groove 8, 8A ... Wheel 8b ... Shaft part 8c ... Convex Part 9: Boss part 10: Convex part 21: Main body (or holder) 23: Central support wall 24: Hollow expanding part 25: Annular convex 26: Detent convex 28: Axle 29: Annular groove 30: Groove ( Grease pool )

──────────────────────────────────────────────────続 き Continued from the front page (56) References JP-A-52-140145 (JP, A) JP-A-59-74103 (JP, U) JP-A-57-85305 (JP, U) JP-A-59-85305 111703 (JP, U) Shokai 55-68602 (JP, U) Shokai Hei 1-154004 (JP, U) Japanese Patent Publication Sho 50-29213 (JP, B2) Shohei 2-7683 (JP, Y2) (58) Field surveyed (Int. Cl. ⁷ , DB name) B60B 33/00

Claims (3)

(57) [Claims] A main body having a hollow expanded portion;
An axle that fits into most of the hollow interior and rotates on the axle
Wheels that can be assembled as much as possible and
The main body, the axle and the wheels are the same or of the same type.
Manufactured separately from a plastic synthetic resin material, and extends in the circumferential direction inside the hollow enormous portion of the main body.
An annular protrusion for retaining the axle, and its intersection with the annular protrusion
Axles that extend in the axial direction to prevent rotation of the axle
The axle is engageable with an annular protrusion for preventing the axle from falling off.
Annular groove, and protrusion and engagement with the axle detent
A possible groove is formed, and the axle is pressed into the hollow expanded portion of the main body.
The annular protrusion and the annular groove engage with each other to prevent the axle from coming off.
And the axle anti-rotation projection and recess engage with each other,
That the axle is fixed to the hollow part of the body
Plastic twin wheel caster, wherein. 2. A grease reservoir is formed in a groove formed in an axle.
The two- wheel caster made of synthetic resin according to claim 1, characterized in that: 3. An annular groove extending in the circumferential direction is formed on the axle.
The inner periphery of the wheel has a convex portion engageable with the annular groove of the axle.
By forming a boss portion to be pressed and press-fitting the boss portion of the wheel into the axle,
The annular groove and the convex portion are fitted, and the wheel is mounted on the axle.
Being relatively rotatable and provided in a retaining state
The synthetic resin twin wheel key according to claim 1 or 2,
Duster.