GB2229975A - Wheel construction - Google Patents

Abstract

A plastics wheel (10), suitable for wheeled articles such as push-chairs, prams, shopping trolleys, baby walkers and the like, is so constructed as to be capable of one stage assembly to a spindle of the article. The wheel 10 comprises a main body having a boss 11 with a bore 12 to receive the spindle and a hollow or solid tyre simulating outer ring 16, linked by a flange (13). The boss has an enlarged outwardly facing seating 19 within which a star lock washer 20 is loosely assembled and a cover member 22 is located within the seating 19 by snap engagement of projections 24 with portions 21, serving the purpose of both covering and trapping the star lock washer 20. The wheel assembly can be supplied as a unit to a manufacturer of wheeled articles for simple single stage push engagement on a spindle of a wheeled article. <IMAGE>

Description

Title: Wheels This invention relates to wheels. It was primarily devised for use in simplifying the attachment of moulded plastics wheels to such items as push-chairs, prams, shopping trolleys, baby walkers and the like at final assembly. Such articles will be referred to in the following description as "wheeled articles11.

Rnown forms of moulded plastics wheel for such uses have an enlarged shell or hollow rim which simulates a tyre or a solid tyre and also have a central fixing boss to receive a spindle on the article to which the wheel is to be assembled. The wheel is conventionally held to the spindle by a star lock washer.

In the conventional method of final assembly of the wheel to the article, the wheel is placed on the spindle and the star lock washer is presented from the outer side and forced onto the spindle to grip it and prevent withdrawal of the spindle from the wheel. This has the disadvantage that the star lock washer remains accessible during use of the article and may cause damage or injury or may be prized off, releasing the wheel.

To reduce these disadvantages, a cover is sometimes fitted to the wheel from the outer side. However, this adds a further assembly operation to the attachment of the wheel by the manufacturer of the finished wheeled article. The three-stage assembly operation of fitting the wheel, star lock washer and cover is time consuming and costly.

It is an object of the present invention to provide a new or improved wheel, capable of single-stage final assembly to a wheeled article.

According to the invention there is provided a wheel comprising a main body including a rim and a central boss having a bore which is adapted to receive a mounting spindle from the inner side of the wheel, the bore having an enlarged seating and a reduced snap portion on the outer side of the wheel, the wheel further comprising a lock washer mounted in said seating, and a cover member including a central portion disposed within said bore and snap engaged with said snap portion to both trap the lock washer and cover the spindle in use.

The main body may comprise a plastics moulding. The main body may be made as a single piece or a two-piece moulding. In the latter case, the rim may be hollow or may be solid.

The central portion of the cover member may comprise a boss having an outwardly facing peripheral projection or projections engaging with the snap portion of the bore.

The invention also provides a kit of parts for making a wheel as set out above, the kit of parts comprising: a main body including a rim and a central boss having a bore adapted to receive a mounting spindle from the inner side of the wheel, the bore having an enlarged seating and a reduced snap portion on the outer side of the wheel; a lock washer adapted to be mounted in said seating; and a cover member including a central portion adapted to be disposed within said bore and adapted to snap engage with said snap portion.

A wheel embodying the invention will now be described in more detail by way of example only with reference to the accompanying drawing which is a partial radial sectional view of a wheel for a wheeled product as defined.

Referring to the drawing, a wheel generally indicated at 10 comprises a boss 11 having a bore 12, a radially extending flange 13 and a rim 14. The rim 14 is hollow and, in the example shown1 is made up of an inner part 15 integral with the flange 13 and an outer, tyre simulating ring 16 which is attached by suitable means to the inner portion 15, leaving a hollow 17. Tread means 18 are provided on the rim 14. In a modified form, not shown, the rim may be arranged to accept a solid tyre.

The central bore 12 of the boss 11 is provided with a seating 19 which receives a star lock washer 20 of spring metal. The washer is merely placed loosely within the seating 19.

On the outer side of the wheel, the bore 12 is enlarged to provide the seating 19 and then has a reduced portion providing a snap formation 21 which may either surround the bore completely or be formed of discrete inward projections.

The snap formation 21 permits the fixing of a cover member 22 which is in the form of a disc having a central boss having an outwardly directed peripheral snap projection 24 which engages with the snap portion 21 of the bore 12. Again, the boss may have a plurality of snap projections 24.

The cover member 22 therefore serves the dual purpose of retaining the star lock washer 20 in the seating 19 and, when the wheel is assembled to a spindle (not shown) also conceals the end of the spindle from access. It is secured to the wheel by an easily engaged single snap fixing.

The extreme free edge 28 of the cover member abuts the outer rim member 16 to provide a smooth attractive finish to the wheel.

In use, the wheel is supplied as a fully assembled unit to the manufacturer of wheeled articles. The only assembly operation which is then necessary is for the wheel to be offered up to the spindle (not shown) on the wheeled article and for it to be pushed into position, engaging the star lock washer 20 with the spindle. The spindle cannot thereafter easily be withdrawn.

In use, the cover member is firmly held onto the remainder of the wheel and both traps the star lock washer 20 and conceals it and the spindle.

Claims (10)

1. A wheel comprising a main body including a rim and a central boss having a bore which is adapted to receive a mounting spindle from the inner side of the wheel, the bore having an enlarged seating and a reduced snap portion on the outer side of the wheel, the wheel further comprising a lock washer mounted in said seating, and a cover member including a central portion disposed within said bore and snap engaged with said snap portion to both trap the lock washer and cover the spindle in use.

2. A wheel according to claim 1 wherein the main body comprises a plastics moulding.

3. A wheel according to claim 2 wherein the main body is a single piece moulding.

4. A wheel according to claim 2 wherein the main body is a twopiece moulding, one piece incorporating said central boss and the other piece incorporating at least part of said rim.

5. A wheel according to claim 4 wherein the rim is hollow.

6. A wheel according to claim 4 wherein the rim is solid.

7. A wheel according to any preceding claim wherein the central portion of the cover member comprises a boss having an outwardly facing peripheral projection or projections engaging with the snap portion of the bore.

8. A kit of parts for making a wheel according to any preceding claim, the kit of parts comprising; a main body including a rim and a central boss having a bore adapted to receive a mounting spindle from the inner side of the wheel, the bore having an enlarged seating and a reduced snap portion on the outer side of the wheel; a lock washer adapted to be mounted in said seating; and a cover member including a central portion adapted to be disposed within said bore and adapted to snap engage with said snap portion.

9. A wheel substantially as hereinbefore described with reference to and as illustrated in the accompanying drawing.

10. A kit of parts for making a wheel substantially as hereinbefore described with reference to and as illustrated in the accompanying drawing.