JP3043363U - Caster wheel holder - Google Patents

Abstract

(57) 【Abstract】 PROBLEM TO BE SOLVED: To realize a highly accurate assembly by omitting an assembling work to a boss part of a vertical support shaft and a bearing. A boss portion (6) rotatably connected to a lower end of a vertical support shaft (3) attached to a vehicle body or the like via bearings (4, 5) around an axis of the support shaft (3) and from the boss portion (6). A caster wheel holder 1 made of synthetic resin, which is a bifurcated arm 7 extending obliquely downward and has a wheel mounting shaft hole 11 having a shaft core orthogonal to the support shaft 3 at a lower end of the arm 7. , The lower end of the vertical support shaft 3 and the bearing 4, on the boss 6.
It is integrally molded with 5 inserted, and a spacer 15 is provided between the bearings 4 and 5.

Description

[Detailed description of the invention]

[0001]

[Technical field to which the invention belongs]

 The present invention relates to a wheel holder for a caster that is mounted on a wheelchair, a carrier, etc. (hereinafter simply referred to as a vehicle body, etc.).

[0002]

[Prior art]

 Castor wheels are used for the front wheels of the wheelchair. As shown in FIG. 6, the wheelchair 30 includes a chair 31, a pair of left and right handles 32 provided on a rear upper part of the chair 31 when a caregiver moves a wheelchair, and a chair 31. A pair of left and right footrests 33 on which a person's foot is placed on a chair 31 provided on the lower front side, and a rear wheel 35 pivotally attached to a rear wheel shaft 34 provided on the rear side of the rear side of the chair 31. , A caster wheel holder 37 rotatably connected to a vertical support shaft 36 provided on both outer sides of the chair 31 slightly behind the footrest 33 so as to be rotatable around the axis of the support shaft 36, and the holder 37. The caster 40 is composed of wheels 39 that are rotatably provided via axle bolts 38.

A front wheel portion is constituted by the support shaft 36, the holder 37, and a caster 40 including caster wheels 39. As shown in FIG. 7, the holder 37 includes a boss portion 43 that holds the vertical support shaft 36 via bearings 41 and 42, and a bifurcated arm extending obliquely rearward and downward from the boss portion 43. 44, a shaft hole 45 having a shaft core orthogonal to the support shaft 36 is provided at the lower end of the arm 44, and the axle bolt 38 is inserted and fixed in the shaft hole 45.

It should be noted that the arm 44 is provided with a fender portion 46 and a reinforcing portion 47, and is designed so that it is not necessary to separately attach the fender. As shown in FIG. 7, a threaded portion 48 is provided at the lower end of the vertical support shaft 36, and a rotation stop nut 49 is screwed onto the threaded portion 48.

[0005]

[Problems to be solved by the device]

 By the way, since a wheelchair has strict safety standards and high precision, it is very troublesome to assemble the vertical support shaft 36 and the bearings 41, 42 into the boss portion 50 of the wheel holder 37, and workability is low. There is a problem of being bad. The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a caster wheel holder capable of obtaining high precision by omitting the work of assembling the vertical support shaft and the bearing into the boss portion. There is.

[0006]

[Means for Solving the Problems]

 In the present invention, the following technical measures were taken to achieve the above object. That is, the present invention is directed to a lower end of a vertical support shaft attached to a vehicle body and the like, and a boss portion rotatably connected around a shaft center of the support shaft via a bearing, and extending obliquely downward from the boss portion. A caster wheel holder made of a synthetic resin, comprising a bifurcated arm, and a wheel mounting shaft hole having a shaft center orthogonal to the support shaft at the lower end of the arm. It is characterized by being integrally formed with the lower end of the support shaft and the bearing being inserted (claim 1).

In this case, the vertical support shaft with the bearing assembled is fitted and fixed at the positions of the bosses in the upper and lower molds of the wheel holder mold, and then the molten synthetic resin is poured into the mold. The boss and the vertical support shaft are integrated via the bearing, and the assembling accuracy can be secured. According to the present invention, the bearing is composed of two sets of upper and lower bearings, and the opposite end portions of the upper and lower bearings project from the upper and lower end surfaces of the boss portion. Each end can be positioned by holding it in a sandwiched manner, and vertical spindles can be inserted with high precision. (Claim 2).

Further, in the present invention, since the resin inflow prevention / spacer is fitted between the upper and lower bearings, it is possible to accurately secure the upper and lower bearing intervals during insert molding of the vertical support shaft, and at the same time, in both bearings. It is possible to prevent the resin from flowing in (claim 3). Further, according to the present invention, a boss portion rotatably connected to a lower end of a vertical support shaft attached to a vehicle body or the like about a shaft center of the support shaft via a bearing, and extending obliquely downward from the boss portion. A caster wheel holder made of synthetic resin, comprising a bifurcated arm provided, and a shaft hole at the lower end of the arm, the shaft hole having a shaft axis orthogonal to the support shaft. It is characterized in that the lower end of the shaft is integrally molded in such a manner that it is inserted into the lower bearing and the upper and lower bearings, which are tightened with nuts from above and below, and the resin inflow prevention / spacer. It is possible to omit the work of assembling the vertical support shaft into the section, and further improve the caster assembly accuracy.

[0009]

[Embodiment of the invention]

 Hereinafter, embodiments of the present invention will be described with reference to the drawings. 1 to 5 show an embodiment of a caster wheel holder 1 according to the present invention. The caster 2 is a vertical support shaft 3 attached to a wheelchair, a vehicle body or the like (see FIG. 6), and a boss 6 is attached to the lower end of the support shaft 3 via two upper and lower bearings 4 and 5 so as to be relatively rotatable. And a wheel 9 attached to the lower end of an arm 7 of the holder 1 via an axle bolt 8 so as to be rotatable about a horizontal axis.

The wheel holder 1 is made of a synthetic resin (for example, nylon), and has a boss portion 6 integrally formed with the vertical support shaft 3 in an inserted state at the time of molding, and extends from the boss portion 6 obliquely rearward and downward. And a bifurcated arm 7. A shaft hole 11 having a horizontal axis perpendicular to the central axis of the boss hole 10 of the boss 6 is provided at the lower end of the arm 7, and the shaft bolt 11 is provided in the shaft hole 11. 8 is inserted and fixed.

Further, the holder 1 is provided with a fender portion 12 extending on the side of the arm 7, that is, on the rear side thereof, which has substantially the same length as the arm 7 and covers about 1/4 of the outer circumference of the wheel 9. A reinforcing portion 13 is integrally provided between the rear portion of the fender portion 12 and the lower portion of the arm 7 so as to connect and reinforce each other. The boss hole 10 is composed of bearing fitting holes 10A and 10B at both ends in the vertical direction and a spacer fitting hole 10C having a reduced diameter between the fitting holes 10A and 10B.

Further, the vertical dimension of the bearing fitting holes 10A, 10B is made shorter than the width of both bearings 4, 5, and the opposite ends of both bearings 4, 5 have upper and lower end surfaces 6A of the boss portion 6, It is designed to project from 6B, and the ends of both bearings 4 and 5 projecting from the end surfaces 6A and 6B are clamped by the upper and lower molds 14A and 14B of the molding die 14 during insert molding of the vertical support shaft 3. Positioning and fixing are done by using this to ensure high accuracy.

The diameter of the spacer mounting hole 10C is the same as the outer diameter of the cylindrical resin inflow preventing / spacer 15 fitted between the bearings 4 and 5, and the outer races 4A of both bearings 4 and 5 are arranged. , 5A, so that the resin does not flow into the bearings 4, 5. The inner diameter of the spacer 15 is made larger than the outer diameters of the inner races 4B, 5B of both bearings 4, 5 so as not to interfere with the rotation of the inner races 4B, 5B of both bearings 4, 5.

As shown in FIG. 4, screw parts 16 and 17 are provided in the lower portion of the vertical support shaft 3, and the screw parts 16 and 17 are provided with detent nuts 18 and 19 (see FIG. 5). The cover 20 is externally fitted to the upper threaded portion 16 and the cover fixing nut 21 is screwed. When the wheel support 1 is formed by inserting the vertical support shaft 3, the bearings 4, 5 and the spacer 15 are fitted under the vertical support shaft 3 as shown in FIGS. The fixing nuts 18 and 19 are tightened and fixed, and then positioned and fixed in the upper and lower molds 14A and 14B of the mold 14.

That is, the ends of the bearings 4 and 5 are fitted into the bearing holding recesses 22 and 23 of the upper and lower molds 14A and 14B, and the nuts 18 and 19 are fitted into the detent nut holding recesses 24 and 25, respectively. The upper and lower molds 14A and 14B are clamped and fixed. In this way, the wheel holder 1 is formed integrally with the vertical support shaft 3 by injecting the molten resin with the vertical support shaft 3 inserted into the molding die 14 together with the bearings 4, 5 and the spacer 15. Since the spacer 15 is provided and the opposite sides of the bearings 4 and 5 are sandwiched and fixed by the upper and lower molds 14A and 14B, it is possible to prevent the resin from flowing into the bearings 4 and 5 and the spacer 15.

According to the above-described embodiment of the present invention, the work of assembling the vertical support shaft 3 and the bearings 4, 5 into the boss hole 10 of the boss portion 4 of the wheel holder 1 can be omitted, and further, they can be integrated by insert molding. Therefore, it is possible to ensure high accuracy and greatly improve work efficiency. Further, the assembling of the bearings 4 and 5 to the vertical support shaft 3 can be performed easily and efficiently, and the accuracy can be secured.

After the wheel holder 1 is completely molded, the cover 20 and the nut 21 are externally fitted from the upper end of the vertical support shaft 3 and the nut 21 is screwed to the screw portion 16 to vertically mount the cover 20. It may be fixed to the support shaft 3. Further, the boss portion 6 of the wheel holder 1 is made thicker than the other portions to increase the strength, but since there is a risk of sink marks during the cooling process after molding, the boss portion 6 6 Take measures to prevent sink marks, such as by providing vertical / horizontal or vertical / horizontal ribs (not shown) on the outer peripheral surface to reduce the wall thickness, or by providing forced cooling means outside the boss molding cavity of the mold 14. Therefore, the accuracy should be secured.

In the above embodiment, the spacer 15 between the bearings 4 and 5 may be omitted and the bearings 4 and 5 may be arranged so that there is no gap, or only one bearing may be provided. The bearings 4, 5 and the spacer 15 can be inserted during the molding of the wheel holder 1, but in this case, a means for holding the spacer 15 is required, and after the completion of the molding, the holding work is removed and the vertical movement is performed. Assembly work for inserting and fixing the support shaft 3 into the bearings 4 and 5 is required. Therefore, the above-described embodiment is more efficient and highly accurate.

The present invention is not limited to the above-described embodiment, and can be applied to, for example, a wheel holder 1 that does not have the fender portion 12 and the reinforcing portion 13. It can also be used on casters that can be attached to legs, trucks, and table legs.

[0020]

[Effect of the invention]

 According to the present invention, as described above, the boss portion of the caster wheel holder is integrally molded with the vertical support shaft and the bearing inserted, so that the work of assembling the vertical support shaft and the bearing into the boss portion is omitted. Therefore, it is possible to improve the assembling workability and accuracy, and it is possible to improve the safety especially in a wheelchair (Claim 1).

According to the second aspect of the invention, the bearing is composed of two pairs of upper and lower bearings, and the opposite end portions of the upper and lower bearings project from the upper and lower end surfaces of the boss portion. When inserting the bearing into the boss portion, the opposite end of the bearing can be positioned outside the cavity of the molding die and positioned and held by the die, thus ensuring high accuracy. Further, according to the third aspect of the invention, since the resin inflow prevention / spacer is fitted between the upper and lower bearings, the bearing interval can be secured and the resin inflow into the bearing can be prevented. It is possible.

[Brief description of the drawings]

FIG. 1 is a central vertical sectional view showing an embodiment of the present invention.

FIG. 2 is a front view of the same embodiment.

FIG. 3 is a left side view of FIG. 2;

FIG. 4 is a partially cutaway side view showing a state in which the vertical support shaft and the bearing are inserted into a mold in the same embodiment.

FIG. 5 is a bottom view of FIG. 4;

FIG. 6 is a perspective view showing an example of a wheelchair.

FIG. 7 is a central vertical sectional view showing a conventional wheel holder.

[Explanation of symbols]

 1 Wheel Holder 2 Caster 3 Vertical Support Shaft 4 Bearing 5 Bearing 6 Boss 7 Arm 8 Axle Bolt 9 Wheel 11 Shaft Hole 15 Spacer

Claims (4)

[Utility model registration claims] 1. A boss portion rotatably connected to a lower end of a vertical support shaft attached to a vehicle body or the like around a shaft center of the support shaft via a bearing, and extending obliquely downward from the boss portion. A caster wheel holder made of synthetic resin, comprising a bifurcated arm, and a wheel mounting shaft hole having a shaft center orthogonal to the support shaft at the lower end of the arm, wherein the vertical support is provided on the boss portion. A caster wheel holder characterized by being integrally molded with the lower end of the shaft and the bearing inserted. 2. The caster wheel holder according to claim 1, wherein the bearing is composed of two pairs of upper and lower bearings, and opposite end portions of the upper and lower bearings project from upper and lower end surfaces of the boss portion. 3. The caster wheel holder according to claim 2, wherein a resin inflow prevention / spacer is fitted between the upper and lower bearings. 4. A boss portion rotatably connected to a lower end of a vertical support shaft attached to a vehicle body or the like around a shaft center of the support shaft via a bearing, and extending obliquely downward from the boss portion. A caster wheel holder made of synthetic resin, comprising a bifurcated arm and a shaft hole having a shaft core orthogonal to the support shaft at the lower end of the arm, wherein the boss portion has a lower end of the vertical support shaft. A caster wheel holder, wherein the caster wheel holder is integrally molded with the upper and lower bearings, which are fitted over the upper and lower parts and tightened from above and below, and a spacer for preventing resin inflow and a spacer.