NZ248748A - Plastics wheel cover for cycles; cover each side of wheel secured together by screws - Google Patents

Description

Pat£* Form No. 5 ;Pal. 5 ;NEW ZEALAND ;2t 87 ;8 ;.' v» i <' ;A V , ;PATENTS ACT 1953 ;COMPLETE SPECIFICATION ;(To be furnished in Duplicate) ;Where priority as provided by subsection (2) or (3) of section II of the Patents Act 1953 is desired in respect of one or more provisional specifications, quote number or numbers and dale or dates ;No.2Al_l^i_ ;Date b CCrp^eR S ;(a) Insert title of Invention. ;(a) C-vy Cv-£ -lAH^TL- OLVletgS ;(b) State (in full) name, address and nationality of arjJicant or applicants as ^Biplication form ;(c) Here begin full description of invention. The continuation of the specification should be upon paper of the same size as this form, on one side only with the lines well spaced and with a margin of 2.5cm on the left hand side of the paper. The completion of the description should be followed by the words "What 1 (or we) claim is" after which should be written the claim or claims numbered consecutively (see note below). The specification and the dup-licate thereof must be signed at the end. ;":f-:oon s i<mi, ;(b) ;^ v> A-s."e"K>vxcE i , qtyv;. ;A- c*» < HEREBY declare the invention, for which 1/we pray that a patent may be granted to me/us and the method by which it is to be performed, to be particularly described in and by the following statement: (c) g-S PriTfa>oTiOr<> Oi.'Sg-t.TgO Ti-vg. c<p c,v|.

NOTE. The claims must relate to a single invention, must be clear and succinct, and must be fairly based on the matter disclosed in the specification. They should form in brief a clear statement of that which constitutes the invention. Applicants should be careful that their claims include neither more nor less than they desire to protect by their patent. Any unnecessary multiplicity of claims or prolixity of language should be avoided.

Claims should not be made for the efficiencv or advantaees of the invention. 1 2-4 ft 7 4 8 American, British and other research has shown that competitive cyclists can improve their competitiveness by up to 4% by using aerodynamic disc-type rear wheels, or disc wheel-covers which produce a similar effect. Full disc wheels are expensive, but the same degree of aerodynamic assistance can be obtained from disc shaped covers fitted to a spoked wheel, at a much lower cost. To be effective, such disc-covers must cover the wheel from hub to rim without possibility of air entry to the inside of the wheel and must remain tightly in contact with the rim. Other designs have attempted to achieve this by means of attached foam rubber rings, adhesives or attachment systems of the type which go under the "VELCRO" trade name. This has been a problem on account of the fact that there are many different widths and cross-sections of rims available and the fit is often poor. The covers must also allow sufficient clearance at the gear-block to ensure that the cycle chain does not contact the cover and impair the operation of the free-wheel. Wheel-covers must also have a valve access aperture for a hand pump to inflate the tyre and must be easily dismountable from the wheel to allow cyclists to remove the wheel-covers if conditions of high side-wind are present on race day, or to service the wheel. Typically, no one design has been able to cater for all these requirements.

Accordingly, the present invention relates to improvements in the design and manufacture of disc wheel-covers for spoked cycle wheels.

The object of the invention is to provide disc wheel-covers at a lower cost than full disc wheels, which will meet all the above-mentioned requirements, while avoiding the complexity of existing designs and methods of attachment.

One preferred form of the invention is now described with reference to the accompanying drawings, of which Fig.l shows a side view and cross-section of a wheel-cover A.

Each rear wheel requires two such covers A, fastened together and held tightly against the wheelrim, as shown in Fig.2, which is a la. •> £? ■f cn .y •. > ^ i ~o cv. xj • cn CO cn , '»• 24 fi 7 4 8 cross section of a wheel fitted with a disc cover on one side. Wheel-cover A is advantageously constructed from a sheet of thermoplastic, typically less than 1 mm thick, preferably formed by the vacuum-forming process and capable of being easily cut using hand scissors. It may have a plurality of conical or contra-conical surfaces as shown in Fig.l. to improve the rigidity of the form. The contra-conical form is achieved by the use of a plurality of conical surfaces, of concave and convex form relative to each other where they meet at common diameters.

Either of the two wheel-covers A may have a valve access aperture V as shown in Fig.3, formed into it such that valve access by a pump may be gained internally. Advantageously, this aperture may have a formed lip around its circumference to stiffen the edge of the aperture. A plurality of fixing-bosses, typically eight, shown at B in Fig.2, are formed in the outer part of each wheel-cover A, and accept lightweight attachment-screws K, shown in Fig.2.

Rim fitting- Close to the circumference of each wheel-cover A is formed a "hinge-groove" D, shown in Fig.2. This hinge in its natural untensioned state, constrains the outer edge of each wheel-cover A to adopt the position shown at C in Fig.2. When the attachment screws K are attached from each side and screwed together, the two wheel-covers A are drawn together until they are in contact with the spokes S of the wheel and the Hinge-groove D is forced to elastically close up to adopt the position shown at E in Fig.2, such that the circumference of the wheel cover A is held in contact, flush with the rim of the wheel by the elastic force of the hinge-groove D, on a diameter which is smaller than that of the brake block position. In this manner, a pair of covers will fit various rim sections and widths, without alteration or the use of internal spacers.

Centre Fitting.

At the centre of each rear wheel-cover A, is a hole J to enable the 2 h, cn

Claims (4)

24 ft 7 4 8 wheel-cover to fit closely over the wheel hub. On the side of the wheel where the gear cluster H in Fig.2, is fitted, this hole may be moulded such that it has a raised edge of several millimetres, as shown at G in Fig.2. This edge G is designed to be crushed by the screwed centre of the gear cluster as it is tightened onto the wheel hub Q in Fig.2, thereby forcing the wheel cover A against the spoke flange of the wheel hub Q. This ensures clearance always exists for the chain, between the gear cluster H and the Wheel-cover A, WHAT I CLAIM IS

1. A pair of wheel covers having a plurality of moulded fixing-bosses through which are passed fixing screws and having an annular hinge-groove moulded into the outer portion of each wheel-cover at a suitable distance from its circumference such that a tightening of the fixing screws produces a holding tension where the circumference of each wheel-cover contacts the wheel rim and sits flush against it due to elastic flexing of the hinge-groove, such that a pair of covers will fit a range of wheel rim widths, without alteration.

2. A pair of wheel-covers as claimed in claim 1 in which one wheel-cover has an integral raised edge around a centre hole to space a gear cluster from the outer face of the wheel-cover.

3. A pair of wheel-covers as claimed in claim 1 in which one or both wheel-covers have a moulded aperture for internal pump access to a tyre valve and where such aperture has an integral stiffened edge.

4. A pair of wheel-covers as claimed in claim 1, where the profile of the cover is moulded into a plurality of concentric conical or contra conical regions and which is constructed from thin, flexible material which can be trimmed to fit a range of different wheel diameters and rims, using only simple hand scissors. 3