GB2054495A - Automobile luggage rack element and a rack - Google Patents

Abstract

An automobile luggage rack comprises two plastics material elements attached at their ends to a roof gutter or other attachment point on the automobile by strap-like fastening members of webbing or rubberised belting. The elements are of a semi-rigid plastics material such as vacuum formed ABS and are made more flexible by having a rib interrupted by recesses which in effect reduce the effective height of the rib (as far as flexibility is concerned in a desired direction) whilst maintaining the normal height at that required. These recesses divide the rib into a succession of inherently strong frusto- pyramids. <IMAGE>

Description

SPECIFICATION Automobile luggage rack element and a rack The present invention concerns automobile luggage racks and elements thereof.

Luggage racks are often used to carry luggage which is too big for the boot or the inside of a saloon car. Such racks can be fitted on top of the passenger compartment or on the boot lid. The usual British rack consists of a rigid platform of tubular construction mounted from the gutters along the sides of the roof and spaced above the roof. They are difficult to remove and instal; if removed they are difficult to store and will not fit within the boot. When installed they are regarded as semi-permanent features which due to wind resistance reduce the automobiles performance and increase fuel consumption. It is also known to have two or more parallel load bearers permanently bolted to the vehicle, which bearers can extend fore-a nd-aft or transversely.

These bearers have been preformed to match the curvature of the vehicle roof, or segmented to give a pseudo-flexibility, or have been mounted fore-andaft where the curvature is slight. When the loads to be supported are such that the loads sink down over a bearer into contact with an automobile roof, it has been usual to provide a great number of bearers closely spaced parallel each other. Whilst this paragraph has been referring to roofs, car racks can be fitted on boot or bonnet lids or on top of lorries and the invention is equally applicable.

The present invention provides an automobile luggage rack element having a base which is relatively broad in comparison with the depth of the element and having apertures for flexible fastening members for securing the element to the automobile, the element being of a semi-rigid plastics material or other semi-rigid material having suffi cientflexibilityforthe element to conform to an automobile surface under reasonable force.

Surprisingly it is found that the flexibility needed to conform to the mounting surface does not impair the performance of the element. The roof holds the element against twisting and so there is no appreciable flexibility sideways due to the broad base. The flexible fastening members can be of woven nylon or polyester webbing extending across the vehicle with clips at the ends for engagement with the vehicle's gutters and with some adjustment. However it is possible to have a short length of rubberised or other extensible webbing attached preferably by means of an adjustable fastener within the element to each end of the element and projecting lengthwise therefrom and arranged to be extended to engage clips at the free ends of the webbing to gutters on the automobile.It has been mentioned that the element is of a semi-rigid material; the most suitable material is an ABS plastics material but a U.V. stabilised polypropylene could be used instead.

The element is conveniently of a sheet of the semi-rigid with a hollow longitudinal rib dished out with recesses at intervals along the rib so that the major part of the rib is of a height or depth suitable for supporting a load clear off the roof of an automobile but the recesses provide parts of greater flexibility due to the reduced height or depth. The portions of the rib between these recesses can resemble frusto-pyramids or truncated pyramids which are of extremely high load bearing shape with little tendency to spread or splay under load which is a difficulty that the prior art seeks to overcome by using a metal capping which capping would make the element rigid in the desired direction of curvature to match the curvature of an automobile roof.

Mention has been made of loads which tend to sink down over bearer elements onto an automobile roof; with the elements of the present invention these loads can be supported as in the prior art by having a large number of closely spaced elements but there is another possibility. The recesses although not basically intended therefor can receive auxiliary transverse (i.e. fore-and-aft of the automobile) load bearers which would be spaced apart by the spacing between the recesses and need only be simple elongate members. The recesses could be designed to clip these auxiliary bearers but these bearers could be loose in the recesses and held in place merely by the load and load tie down ropes.

An embodiment of the invention will now be described, by way of example, with reference to the accompanying drawings in which: Figure lisa view showing two elements according to the present invention fitted to an automobile, Figure 2 is a longitudinal section of an element, and Figure 3 is a view taken on line Ill-Ill of Figure 2.

Figure 1 shows an automobile 11 fitted with two transverse elements 12 as illustrated in Figures 2 and 3, each of which is of a weather-resistant ABS or U.V.

stabilised polypropylene of suitable semi-rigid flexibility. Starting with a 2mm sheet of ABS plastics material, it is possible to vacuum form it into the shape as shown in Figures 2 and 3; polypropylene is best blow moulded. The shape is best describd as having a trapezoidal bearing surface rib 14 raised from a flat base 15 with the rib being of different heightalong its length so as to provide recesses 16 along the outer load bearing surface. These recesses are intended for the reception of auxiliary load bearing members (not shown) but also serve a useful mechanical function. The elements can be regarded as inverted open-top flanged boxes which have the property of nesting one in another.The end walls 17 of the ribs have slit-like apertures 18 in them into which apertures pass rubberised or other stretchyfastening members 19 having at their extreme outer ends clips 20 for engaging automobile roof gutters and at their inner ends within the rib an adjustable buckle-like adjustment 21. At each end of the elements, there is conveniently a pronounced raised part 22 of the rib to stop articles sliding along and off the end of the rib.

A great deal of the troubie in evolving the invention resided in obtaining the flexibility to conform to an automobile roof whilst retaining adequate stability and mechanical strength and rigidity. It is considered that important features are that each element is imperforate except for the apertures 18 so there is nothing for luggage to snag on, and that the rib necessary to space the luggage from the car roof has recesses. With a element width of say 10 cm and a length of say 88.5 cm, the rib depth can be say 2.5 cm which is locally reduced to 1cm by the recesses. Each element will thus have the flexibility of an element a mere 1 cm high or deep (indeed due to the recesses having curved roots 23, it is arguable whether the top of the rib adds to rigidity).These recesses and the generally imperforate nature of the elements entail that the sides of the ribs are joined together by webs 24 (Figure 3) low down so that the sides will not be able to splay out under load or as a result of the elements being flexed to conform to an automobile roof. These recesses also divide the rib into a sequence of mechanically strong frusto-pyramids which are rigidly mounted.

The invention thus proves that it is possible to have an effective automobile roof rack element which apart from the fastening means can be made as a single component of a plastics material without requiring reinforcement by metal cappings. The recesses serve an auxiliary purpose in that they are also handy for receiving auxiliary load bearing members extending fore-and-aft of the automobile.

The elements can be provided with neoprene or other strips 25 to protect the automobile surface from damage. Such strips serve also to give a frictional grip between the automobile and the elements so that when the elements are curved over the vehicle roof, the elements combine with the automobile roof to form arched hollow box sections supporting the load which is not merely transferred straight to the automobile roof. Shackles 26 are provided on the clips 20 for fastening ropes tying on the luggage; these shackles can be useful as a grip when stretching the members 19 which for safety should be very taut.

It will be appreciated that the elements of the present invention are easily fitted to an automobile and lie snugly on the automobile reducing wind resistance and fuel consumption. They are as easy to remove and very easy to store possible in a vehicle boot.

Claims (6)

1. An automobile luggage rack element having a base which is relatively broad in comparison with the depth of the element and having apertures for flexible fastening members for securing the element to the automobile, the element being of a semi-rigid plastics material or other semi-rigid material having sufficient flexibility for the element to conform to an automobile surface under reasonable force.

2. An element as claimd in claim 1 wherein the element is a one-piece moulding with a hollow upstanding rib extending from a flange-like base, the rib having an open bottom and being of different depth along its length so that the upper surface has a succession of recesses which reduce the effective depth of the rib as far as flexibility to conform to the said surface is concerned.

3. An element as claimed in claim 2 wherein the rib is trapezoidal in cross-section and wherein the recesses divide the rib into a succession of frustopyramids and wherein apart from the fastening apertures the element is imperforate.

4. An element as claimed in claim 2 or 3 wherein the recesses reduce the depth of the rib to at least half of the depth elsewhere and wherein the recesses have rounded roots.

5. An automobile roof rack element substantialiy as herein described with reference to the accompanying drawings.

6. An automobile roof rack comprising a pair of elements as described herein mounted transversely of an automobile as illustrated in Figure 1 of the accompanying drawings.