GB2327912A - Vehicle protection bar - Google Patents

Abstract

A protection bar for attachment to the front of a land vehicle comprises an inflexible, rotationally moulded frame encased in a body of cushioning material. As shown, fig 3, the unit comprises upright arms 10 connected by cross-pieces 14, 16 made by rotational moulding and covered by an outer cushioning body 22.

Description

VEHICLE PROTECTION BARS This invention is concerned with improvements, in or relating to the provision of protection bars on the front of land vehicles.

In different parts of the world, such protection bars as the invention relates to are known as roo bars, nudge bars and bull bars. The bars are arranged for the protection of both the vehicle body, in the event of a frontal impact with an animal or person, and also to minimise injury to that animal or person.

In their most basic form, protection bars can be constructed as a self-supporting framework of metal sections (e.g. round tube) which is secured to the vehicle front. To minimise personal injury which can be caused by such a rigid framework, the framework can be embedded in a cushioning material such as a resilient polyurethane material.

Such protection bars based on a metal framework are heavy and expensive to manufacture.

For lighter duties, it is known to replace the metal framework with a vacuum - formed plastics section; the section is encased in an ABS plastics or polyurethane material to give the finished product. However, whilst lighter and cheaper to manufacture, such vacuum-formed sections are liable to twist and flex in certain directions and it is, therefore, necessary to have many fixing points in securing the product to a vehicle.

It is an object of the present invention to provide protection bars of generally improved construction.

The invention provides, in one of its aspects, a protection bar unit for securement to the front of a land vehicle and comprising an inflexible rotationally - moulded frame encased in a body of a cushioning material.

Whilst the frame may be moulded of a blown material, which at least in thinner sections of the frame may tend towards filling the otherwise hollow moulded section, it can with advantage be moulded to produce hollow sections which can subsequently be filled with an energyabsorbing material such as a low density rigid polyurethane. Glass reinforcement may be introduced into the sections before filling. The moulded frame may encapsulate fixings, metalwork, etc.

Suitable materials for the rotationally - moulded frame may include high or medium density polyethylene, nylon (e.g. 6, 6.6, 11 or 12), polypropylene and ABS plastics materials.

The outer cushioning may be of any suitable plastics material, e.g.

polyurethane which may be moulded in integral skin, RIM or elastomer skin form.

There now follows a description, to be read with reference to the accompanying drawings, of a nudge bar unit which illustrates the invention by way of example.

In the accompanying drawings Figure 1 is a perspective view of the unit; Figure 2 is a similar perspective view of a rotationally moulded frame of the unit; Figure 3 is a centre vertical section through the unit; and Figure 4 is a horizontal section through a fixing point on one limb of the unit.

A nudge bar unit (Figure 1) for attachment to the front of a vehicle comprises two bowed upright arms, 10 and 12 which are interconnected at the top by means of an upper cross-piece 14 and at a lower position by means of a lower cross-piece 16; approximately two-thirds of the lengths of the arms extends below the lower cross-piece.

The unit, seen in cross-section in Figure 3, comprises a rigid rotationally - moulded frame 18 (Figure 2) of a similar general form to the unit. The frame is stiff and inflexible, each limb 20 of the frame (i.e.

arms and cross-pieces) being moulded as a hollow section. The frame is rotationally moulded in one piece of a suitable grade of polyethylene.

The hollow rotationally-moulded frame can be filled, after moulding, with a low density rigid polyurethane foam. Glass reinforcement may be introduced, if required, into the energy-absorbing foam.

An outer cushioning body 22 of polyurethane is moulded to encase the frame.

The unit can be secured in place on a vehicle by fixings including mounting brackets 24, 26 (Figures 2 and 4) which engage the arms 10, 12 immediately beneath the lower cross-piece 16.

Claims (13)

1. A protection bar unit for securement to the front of a land vehicle and comprising an inflexible rotationally-moulded frame encased in a body of a cushioning material.

2. A unit according to claim 1, wherein the frame is moulded of a blown material.

3. A unit according to claim 1, wherein the frame is moulded to produce hollow sections.

4. A unit according to claim 3, wherein the hollow sections are subsequently filled with an energy-absorbing material.

5. A unit according to claim 4, wherein the energy-absorbing material is a low density rigid polyurethane.

6. A unit according to any of claims 3 to 5, wherein glass reinforcement is introduced into the sections before filling.

7. A unit according to any preceding claim1 wherein the moulded frame encapsulates fixings1 metalwork, etc.

8. A unit according to any preceding claim1 wherein the rotationallymoulded frame is formed from high or medium density polyethylene, nylon (e.g. 6, 6.6, 11 or 12), polypropylene or ABS plastics materials.

9. A unit according to any preceding claim, wherein the outer cushioning is of plastics material.

10. A unit according to claim 9, wherein the plastics material is polyurethane.

11. A unit according to claim 9 or 10, wherein the outer cushioning is moulded in integral skin, RIM or elastomer skin form.

12. A protection bar unit substantially as described above, with reference to the accompanying drawings.

13. Any novel subject matter or combination including novel subject matter disclosed herein, whether or not within the scope of or relating to the same invention as any of the preceding claims.