WO1997028863A1

WO1997028863A1 - Skateboard suspension

Info

Publication number: WO1997028863A1
Application number: PCT/AU1997/000072
Authority: WO
Inventors: Sean Patrick Herbert
Original assignee: Sean Patrick Herbert
Priority date: 1996-02-09
Filing date: 1997-02-10
Publication date: 1997-08-14
Also published as: AUPN797496A0

Abstract

A wheel suspension assembly for a skateboard (10) has a substantially elastically deformable spring member (18) which is of a generally U-shaped cross section and may be made of a plurality of carbon fibre strips resin bonded together to provide the substantially elastic deformability required for effective suspension characterisitics. The spring member (18) has a first planar end portion (22), in the form of a broadly dimensioned base plate, which is connected rigidly to the underside of the platform (12) for the skateboard (10), and a second planar end portion (28) to which is connected a truck (32) for a pair of wheels (36). The first and second planar end portions (22, 28) are interconnected by a folded joint portion (42) defining a bend in the spring member (18) about which deformation occurs, and having a lower part in the form of a concavely shaped neck piece (50) which has a narrower minimum width than the adjoining first and second planar end portions (22, 28). There is a kink (46) between the neck piece (50) and the second planar end portion (28) which, along with the elastic deformation characteristics of the folded joint portion (42), enable movement of the truck (32) relative to the first planar end portion (22) under weight applied by a skateboard rider for the purposes of suspension and steering.

Description

SKATEBOARD SUSPENSION FIELD OF INVENTION

The present invention relates to skateboards and, in particular, to a wheel suspension assembly for a skateboard. BACKGROUND ART

Conventional skateboards have a very limited wheel suspension capability as their trucks are designed to maintain optimal rigidity between the platform upon which the skateboard rider stands and the two pairs of wheels. Each of the two trucks have a rubber cushion and steel strut assembly that may, by the rider's transference of weight, be used for limited steering purposes. However, the rubber forming the cushion has a very high density because of its need to support the rider's weight, therefore making it hard and unable to provide significant suspension characteristics. The absence of an adequate wheel suspension assembly for skateboards has limited the range of skateboard manoeuvres of which a rider may be capable. Furthermore, the enjoyment and protection from injury of a rider will be improved by providing skateboards with an effective wheel suspension assembly. It is therefore an object of the present invention to overcome the shortcomings of the prior art. SUMMARY OF THE INVENTION

According to the present invention, there is provided a wheel suspension assembly for a skateboard, comprising a substantially elastically deformable spring member, said spring member being generally U-shaped in cross-section, and means for connecting a first planar end portion thereof to an underside portion of a platform of the skateboard and means for connecting a second planar end portion thereof, being opposite the said first planar end portion, to a truck for a pair of wheels, said spring member being substantially elastically deformable so as to allow movement of the said truck relative to the said first planar end portion under weight applied by a rider of the skateboard.

Preferably, the generally U-shaped cross-section of the spring member is configured so that, under a rider's weight, the second planar end portion is in substantially parallel spaced apart relationship to the first planar end portion. The spring member may include a folded joint portion defining a bend in the spring member about which deformation occurs, and the first and second planar end members are separately integrally connected to opposite ends of the folded joint portion. In this instance, there is a kink between the second planar end portion and the end of the folded joint portion to which it is integrally connected.

BRIEF DESCRIPTION OF THE DRAWINGS

In order that the invention may be readily understood and put into practical effect, reference will be made to the accompanying drawings in which:- Fig. 1 is a side elevational view of the front end of a skateboard showing a wheel suspension assembly according to a preferred embodiment of the present invention, Fig. 2 is a side elevational view of the rear end of the skateboard of Fig. 1 , Fig. 3 is a rear end view of the skateboard of Fig. 1 , and

Fig. 4 is a underside view of the skateboard of Fig. 1 showing only the generally U-shaped spring member of the wheel suspension assembly. MODES FOR CARRYING OUT THE INVENTION

The skateboard 10 shown in Figs. 1 to 4 has a conventional platform 1 2 (upon which a rider stands) with upturned ends 14, 1 6. Connected adjacent to both the front end and rear end of the platform 1 2 are generally

U-shaped spring members 1 8, 20 which are substantially elastically deformable. Each spring member 1 8, 20 consists of a configuration of carbon fibre strips and resin composites that bind the carbon fibre strips together to provide the substantially elastic deformability required for effective suspension characteristics. The spring members 1 8, 20 are, in this instance, made by casting in a mould, but may be injection moulded.

Each spring member 1 8, 20 has a first planar end portion 22, 24, respectively, that is connected to its adjacent underside portion of the platform 1 2 by a plurality of nut and bolt arrangements 26, 27 respectively. There is a second planar end portion 28, 30 for each spring member 1 8,

20, respectively, that is connected to a conventional truck 32, 34 respectively, for a pair of wheels 36, 38, respectively, by a plurality of nut and bolt arrangements 40, 41 respectively.

There is a folded joint portion 42, 44 defining a bend in each spring member 1 8, 20, respectively, about which deformation occurs. The first and second planar end members 22, 28 of spring member 1 8 are separately integrally connected to opposite ends of the folded joint portion 42 and there is a kink 46 between the second planar end portion 28 and the end of the folded joint portion 42 to which the end portion 28 is integrally connected. A similar kink 48 is present between the folded joint portion 44 and the second planar end portion 30 of spring member 20. Referring specifically to Fig. 4, the first planar end portion 22 is in the form of a broadly dimensioned base plate for optimal connection stability to the platform 1 2, and the lower part of the folded joint portion 42 is in the form of a narrower concavely shaped neck piece 50 that provides swinging arm characteristics to enable the second planar end portion 28 to move vertically relative to the first planar end portion 28 over a wider displacement (under weight applied by a rider of the skateboard) than is presently possible with conventional skateboards. The symmetrically arranged apertures 52 which engage the nut and bolt arrangement 40 for the truck 32 are also shown.

When under the rider's weight, the second planar end portion 28 will be in substantially parallel spaced apart relationship to the first planar end portion 22 by virtue of the deformation characteristics of the folded joint portion 42 and the kink 46. The ability of each spring member 1 8, 20 to allow movement of the truck relative to the first planar end portion from the angle shown in Figs. 1 and 2 to a substantially parallel spaced apart relationship, under the rider's weight, has been found to be most efficient for achieving the purposes of suspension and steering. Various modifications may be made in details of design and construction without departing from the scope and ambit of the invention.

Claims

1 . A wheel suspension assembly for a skateboard, comprising a substantially elastically deformable spring member, said spring member being generally U-shaped in cross-section, and means for connecting a first planar end portion thereof to an underside portion of a platform of the skateboard and means for connecting a second planar end portion thereof, being opposite the said first planar end portion, to a truck for a pair of wheels, said spring member being substantially elastically deformable so as to allow movement of the said truck relative to the said first planar end portion under weight applied by a rider of the skateboard.

2. The wheel suspension assembly of claim 1 wherein the generally U- shaped cross-section of the spring member is configured so that, under a rider's weight, the second planar end portion is in substantially parallel spaced apart relationship to the first planar end portion.

3. The wheel suspension assembly of claim 1 wherein the spring member includes a folded joint portion defining a bend in the spring member about which deformation occurs, and the first and second planar end members are separately integrally connected to opposite ends of the folded joint portion.

4. The wheel suspension assembly of claim 3 wherein there is a kink between the second planar end portion and the end of the folded joint portion to which it is integrally connected.

5. The wheel suspension assembly of claim 1 wherein the spring member consists of a configuration of carbon fibre strips and resin composites that bind the carbon fibre strips together to provide the substantially elastic deformability required for effective suspension characteristics.

6. The wheel suspension assembly of claim 4 wherein the folded joint portion has a lower part in the form of a concavely shaped neck piece which has a narrower minimum width than the adjoining first and second planar end portions.

7. The wheel suspension assembly of claim 6 wherein the second planar end portion is connected to a truck for a pair of wheels by a nut and bolt arrangement.