GB2436547A - Cycle carrier - Google Patents

Abstract

A bicycle carrier is pre-stressed by a tension member 22 extending between the rear of the carrier 15 and an upright limb 16 at the front of the carrier. Load capacity is thereby enhanced. Tension members at each side of the carrier may be provided, and the or each tension member may be incorporated in a container 21 for attachment to the platform 12 of the cycle carrier.

Description

<p>1 2436547</p>

<p>CYCLE CARRIER</p>

<p>This invention relates to a carrier suitable for a bicycle, particularly a bicycle having rear suspension.</p>

<p>Most typically carriers for bicycles comprise a frame of steel or aluminium extending rearwardly from the seat tube and having depending legs mounted on either side of the rear wheel, in the vicinity of the apex between seat stay and rear stay.</p>

<p>The carrier frame defines a generally horizontal platform extending over the rear wheel, and is adapted to support items thereon.</p>

<p>Recently it has become popular to equip bicycles with suspension. Rear suspension is typically by trailing arm pivoted close to the bottom bracket. As a result the axis of the rear wheel moves in relation to the seat tube and the conventional seat and rear stays are not provided. The consequence of this is that the legs of a conventional carrier frame can no longer be provided because there is no longer a</p>

<p>suitable mounting.</p>

<p>One solution is to provide the rear carrier as a simple cantilever extending rearwardly from the seat tube. However bending stress under load is considerable, and consequently such a carrier tends to be of rather heavy construction. A further difficulty is that, if possible, carrier fixings should be via standard mountings, to permit removal and replacement.</p>

<p>It is possible to triangulate such a carrier, either from above or below, but weight is added, and the carrier fixings become more complex.</p>

<p>According to the present invention there is provided a carrier for a bicycle and comprising a rigid frame having a platform, a bicycle frame fixing at one end of the platform and an upright adjacent said one end, wherein a tension member is provided to extend between a mounting at the other end of said platform and a mounting at the free end of said upright, the tension member being shorter than the distance between said mountings.</p>

<p>Such an arrangement permits the tension member to pre-stress the platform upwardly against downward bending forces due to loads on the carrier. As a result, the carrier can be of lighter construction for a given load, and is in use rigid. The invention is characterised by pre-stressing of the platform by the tension members.</p>

<p>The tension member(s) may be rigid, or may be a flexible component such as a wire rope or cable. The tension member(s) may be removable, and furthermore may be adjustable in length. The tension member(s) may be provided separately, or may be incorporated within a container, such as a bag or a box.</p>

<p>The upright may be defined by any suitable structure adapted to provide a mounting above the platform in use, so as to provide suitable triangulation for the carrier.</p>

<p>The upright may for example comprise a limb extending upwardly from said platform at an angle thereto. In the preferred embodiment said limb extends away from said other end of said platform at an acute angle to define with said platform a fork. In use the free ends of said fork combine with a seat tube or seat of a bicycle frame to define a triangle. Such limbs may be provided at either side of the carrier to provide increased lateral stability.</p>

<p>Preferably the mounting of the upright is immediately adjacent a fixing of the bicycle frame, and may be coincident therewith. In a preferred embodiment, fixing at the bicycle frame is via two spaced locations of the seat tube, the upper location preferably being at or adjacent a seat pin clamp.</p>

<p>Other features of the invention will be apparent from the following description of a preferred embodiment shown by way of example in the accompanying drawings in which: Fig. 1 is a side elevation of a carrier frame according to the invention; Fig.2 is a side elevation of a container for integral mounting on the frame of Fig. 1; Fig.3 is a side elevation showing the frame and container in combination.</p>

<p>Fig.4 is a side elevation showing the frame and an alternative container, in combination.</p>

<p>With reference to the drawings, a seat tube 10 of a bicycle frame terminates at an open mouth 11 adapted to receive a seat pin (not shown).</p>

<p>Extending rearwardly from and generally horizontally of the tube 10 is a platform 12 of a carrier. The carrier platform is typically a rectangular lattice in plan, and has a forwardly extending arm 13 on either side for mounting at a lug or clamp of the seat tube, e.g. by screw 14. The arms 13 tend to come together at the forward end so as not to impede leg movement during cycling. The carrier may be of tubing, or of rod, and is typically of steel or aluminium.</p>

<p>Extending up from either side of the platform 12 is a limb 16 for connection to the top of the seat tube for example via the usual clamp bolt 17 for the seat pin. The limbs are fixed to the platform, and together with the seat tube define a rigid somewhat triangular structure for supporting vertical and cantilever loads on the platform, in the general direction of arrow 18. The fixing of the limbs to the platform may be by way of a pivot (for example using a loose rivet) to permit the limbs to adopt an angle suitable for the fixings of the bicycle frame, and to permit the limbs to fold flat for packaging and storage.</p>

<p>The limbs 16 come close together at the seat tube, but may be curved or bent outwardly so as not to encroach upon the carrying surface of the platform. Straight limbs are however desirable for transmitting forces in compression and tension.</p>

<p>The limbs 16 may extend further to the rear of the carrier platform.</p>

<p>At or near to the apex of the limbs 16, an upwardly facing hook 19 is provided. The hook may be provided at any suitable location, for example on the carrier, on the seat tube, or on the seat pin.</p>

<p>The container 21 of Fig.2 is of any suitable size and shape appropriate to the platform 12. It may be an open box, a flexible zipped bag, or any other desirable form. A tension member 22 extends on either side from front to back. At the front the member 22 is adapted to engage the hook 19, and at the rear a hook 23 is provided for engagement with a rear frame member 15.</p>

<p>The tension member 22 is slightly shorter than the distance between the rear frame member 15 and the eye of the hook 19, SO that when fitted (as illustrated) the platform is stressed upwardly, in the direction of arrow 24, thus placing the limbs 16 in compression.</p>

<p>Thus the platform is supported, and better able to resist downward loads. The additional weight is slight, and the tension exerted by member 22 can be any desired amount within the resilient deformation range of the platformllimb assembly.</p>

<p>The tension member may comprise substantially straight links extending from either side of the rear of the platform to the hook 19. Alternatively these links may be connected at the front by a transverse bar so as to define a substantially U' shaped member better able to accommodate a rectangular box or bag. The tension member may be incorporated in the walls of the container 21. Any suitable shape of tension member will suffice so long as the limbs 16 can be placed in compression to some degree.</p>

<p>Fig.4 illustrates the use of an alternative container with flat base 31 incorporating the tension member(s). The platform provided by the base 31 enables the container 32 to be of a dual purpose type, such as a rucksack/bicycle bag. In use as a sucksack, the tension member(s) act to stiffen the back thereof, as is desirable in such containers. The base 31 may comprise all or part of the tension member(s).</p>

<p>Although described in relation to a bicycle with rear suspension, it will be appreciated that the invention is also suitable for conventional bicycles, tricycles and the like, and can be adapted for front mounting by connection to the frame headstock. The hooks 19,23 are examples of suitable fixings, but many other types of mounting can be considered, including semi-permanent or permanent fixings.</p>

<p>One suitable means of adjusting the tension in the tension member 22, is a turnbuckle.</p>

Claims (8)

1. <p>CLAIMS</p>

   <p>1. A carrier for a bicycle and comprising a rigid frame having a platform, a bicycle frame fixing at one end of the platform and an upright adjacent said one end, wherein a tension member is provided to extend between a mounting at the other end of said platform and a mounting at the free end of said upright, the tension member being shorter than the distance between said mountings.</p>

   <p>
2. 2. A carrier according to claim 1 wherein said tension member is flexible.</p>

   <p>
3. 3. A carrier according to claim I wherein said tension member is rigid.</p>

   <p>
4. 4. A carrier according to any preceding claim wherein said tension member is removable.</p>

   <p>: * 15
5. 5. A carrier according to any preceding claim wherein said tension member is :*.::: adjustable in length. I...</p>

   <p>
6. 6. A carrier according to any preceding claim wherein said tension member is * a container for said platform. * **</p>

   <p>:.
7. 7. A carrier according to any preceding claim and having a plurality of tension *.SSSS * members.</p>

   <p>8. A carrier according to any preceding claim wherein said upright comprises a limb extending upwardly from said platform and away from said other end of said platform at an acute angle.</p>

   <p>9. A carrier according to claim 8 wherein said upright and platform together define a fork, the free ends of said fork being adapted for connection to a seat tube of a bicycle frame, to define a triangle in use.</p>

   <p>10. A carrier according to claim 9 wherein the free end of said upright is adapted for connection at a seat pin clamp.</p>

   <p>11. A carrier for a bicycle substantially as described herein with reference to the accompanying drawings.
8. S. 15 * * * III S... * . S...</p>

   <p>SI II * I S * S S.. * *5 1 S</p>

   <p>S</p>

   <p>*.SSSS</p>

   <p>S S</p>