GB2178967A - Roller skates - Google Patents

Abstract

A roller skate, preferably forming part of a boot, comprises an elongated platform having a wheel in the shape of an asymetrical spheroid mounted at or towards each end of the platform for free rotation about a spindle 5. <IMAGE>

Description

SPECIFICATION Improvements in or relating to a roller skate This invention relates to an improved roller skate namely a skate mounted on small wheels and which according to its design can be secured either permanently or temporarily to a boot or a shoe.

The design of a satisfactory roller skate is confronted by a number of conflicting requirements. On one hand a roller skate is required to be used on surfaces which can vary greatly in smoothness from fairly rough concrete, asphalt or paving stones to smooth flooring made from wood or sheet material made from synthetic plastics. The material forming the wheels must not only be able to withstand these conditions but it must not damage the surface especially if it is provided by a smooth floor made of wood which can be costly.

Finally the frictional conditions between the surface and the skate wheels must be such that satisfactory control can be maintained by the skater over the skate.

During the evolution of the roller skate to its present day form more than four wheels were employed.

However it was found latterly that four wheels or less were sufficient to permit the skater to maintain control.

A further defect of known skates it that their designs do not reflect the asymetrical forces which are applied to the wheels by the skater during the skating movement. Thus in order to achieve forward movement the legs of the skater are driven alternately away and to the rear of his body thus causing the skate to keel over in the direction of his body. When a skate has four wheels this keeling movement is hindered.

Since the major part of all movement of a skater is in the forward direction a resulting major part of the life of a wheel is spent in being subjected to forces causing it to keel towards rather than away from the skater.

I have now discovered that a roller skate can be made which is lighter, faster and more manoevreable when it incorporates as wheels two spheroids of asymetrical shape.

Accordingly this invention provides a roller skate comprising an elongated platform having means for attachment to footwear and a wheel having the shape of an asymetrical spheroid mounted for free rotation at or towards each end of the platform about a spindle, the spindle comprising an inner spindle part and an outer spindle part the inner part being longer than the outer part.

This invention is illustrated by the following drawings in which: Figure 1 is an exploded view in perspective of one form of invention roller skate.

Figure 2 is a view taken in vertical section along the direction AA in Figure 1.

In Figure 1 a platform (1) made conveniently from cast aluminium containing a mineral fibre reinforcement is provided with bolt holes (2) for accommodating bolts extending from the sole (not shown) of a skating boot. Platform (1) has depending from it four brackets (3) between which a wheel (4) in the form of an asymetrical spheroid is secured by a spindle (5) passing through U shaped recesses (6) in brackets (3). The wheel is free to rotate about a bearing consisting of a ball race (7) set into the wheel and the ball bearing assembly (8).

Figure 2 shows more clearly the form of the wheel used in invention roller skate. Wheel (4) consists of hard polypropylene and was made conveniently by a turning operation performed on a solid rod of the material. Other materials can also be used although synthetic plastics for example nylon and other polyamides are preferred. The wheels can also be made by casting or any other convenient method of manufacture. The diameter of the wheel as measured along an axis at right angles to the spindle (5) can be conveniently about 40-60 mm preferably 50 mm. The wheel rotates about spindle (5) which passes through bearing assembly (7 and 8) set in a recess within the wheel.

The shape of the wheel is important. The surface contacting part of the wheel (9) is substantially flat so that while the shape of the wheel is generally spheroidal the periphery of the wheel nevertheless makes an area rather than point contact with a smooth surface. The amount of the total surface of the wheel which is flat can vary but preferably is from 25% to 40% of the total surface. The wheel is made preferably in the first instance with the desired area of flatness.

However it is also possible to use materials or a method of construction which results in a wheel at the time of manufacture being completely curvilinear but which acquires the desired degree of flatness during use whether by wear or compression.

The present wheels are asymetrical in shape and the periphery of each wheel is in effect divided into two surfaces the first of which is an inner periphereal surface (10) that is the part of the surface which is directed towards the corresponding surface of a wheel of a second skate when the latter is positioned alongside the first skate. This occurs when for example the skater is either stationary or is gliding along under his own momentum whilst not using any leg action.

The second surface of the wheel is the outer periphereal surface (11) and this is directed generally in the opposite direction from the inner surface and away from the adjacent skate. In the present wheels the curvature of the inner surface is greater than that of the outer surface and part (12) of spindle (5) around which revolves that part of the wheel bounded by the outer periphereal surface (10) is longer than part (13) of the spindle around which revolves the part of wheel bounded by the outer periphereal surface (11). To assist in the description of this invention the former part is referred to as the inner spindle part and the latter part is referred to as the outer spindle part. The lengths of the two parts can vary for example from 18 to 24 mm and is preferably about 22 mm in the case of the inner spindle part and from 16 to 20 mm and is preferably about 18 mm in the case of the outer spindle part. Measurements are taken from the intersection of plane (14) which passes through the mid point of surface contacting area (9) of the wheel and at right angles to spindle (5).

The present skate can be modified in different ways.

Thus if the skate is required to be fixed removably to the rear end of the platform can terminate in a heel cup and strap whilst the front end can be provided with adjustable grips which engage with the welt of the shoe. The front end can also be fitted with a buffer.

Preferably the skate forms an integral part of a skating boot.

Claims (9)

1. A roller skate comprising an elongated platform having means for attachment to footwear and a wheel having the shape of an asymetrical spheroid mounted for free rotation at or towards each end of the platform about a spindle, the spindle comprising an inner spindle part and an outer spindle part the inner part being longer than the outer part.

2. A roller skate according to Claim 1 wherein the length of the inner spindle part lies within the range of 18 to 24 mm and the length of the outer spindle part varies within the range of 16 to 20 mm.

3. A roller skate according to either of Claims 1 and 2 wherein the wheel is made from a turning operation performed on a rod of a synthetic plastics material.

4. A roller skate according to any one of the preceding claims wherein the wheel is made by casting process utilising a synthetic plastics material.

5. A roller skate according to any one of the preceding claims wherein the platform is made from cast aluminium containing a mineral fibre reinforcement.

6. A roller skate according to any one of the preceding claims wherein from 25 to 40 percent of the surface of the wheel enters into contact with the surface on which the skate is used.

7. A roller skate according to any one of the preceding claims wherein the skate forms an integral part of a boot.

8. Roller skates as hereinbefore claimed in any one of the preceding claims.

9. Roller skates as hereinbefore described with particular reference to the drawings.