GB2437499A

GB2437499A - Vehicle nudge bar

Info

Publication number: GB2437499A
Application number: GB0608189A
Authority: GB
Inventors: William C Fortune; William Charles Fortune
Original assignee: BREED GROUP Ltd; TOUCHFIRST Ltd
Current assignee: BREED GROUP Ltd; TOUCHFIRST Ltd
Priority date: 2006-04-26
Filing date: 2006-04-26
Publication date: 2007-10-31
Also published as: GB0608189D0

Abstract

A vehicle nudge bar comprising:- ```a backing support 15 ; ```an energy absorbing impact material mounted on said backing support, ```wherein said energy absorbing material comprises a honeycomb structure 16, having an impact face; ```a moulding 17 of a resilient material formed around said impact face; ```a mounting means 13 adapted to mount said backing support to a vehicle. The crush strength of the nudge bar (bull bar) may be variable across its width and height, this being due to the honeycomb structure comprising different densities or materials.

Description

I

Vehicle Nudge Bar

Field of the invention

This invention relates to so called nudge bars. It is particularly applicable, but in no way limited, to nudge bars for protecting the fronts vehicles which include 4X4 vehicles and other off road vehicles.

Backciround to the Invention Nudge bars for protecting the front of vehicles are often provided on cross-country vehicles such as "Land Rovers" (RTM) and "Range Rovers" (RTM). These are typically provided to protect both the vehicle and passengers during accidents involving collision with animals or other obstacles in the road.

Nudge bars have been known for many years (eg from UK Patent Specification No 1569052) and generally comprise a pair of spaced vertical bars whose front surfaces provide the most forward parts of the nudge bar, one on either side of the vehicle radiator and usually a horizontally extending elongate loop which connects with the two vertical bars. The loop usually wraps around from the front to the sides of the vehicle at its ends. As discussed in said UK Patent Specification, vehicles at that date were commonly provided with bumper bars but these were not sufficient in many instances to provide the required degree of protection.

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.

Known nudge bars are thus generally of grid-like construction, being assembled from substantially horizontal tubular metal bars secured to substantially upright lengths of metal which in turn are generally secured to the chassis, or to an extension of the chassis, of the vehicle and were originally designed for use on vehicles for moving large animals out of the path of the vehicle but which are now frequently used for aesthetic purposes to improve the look principally, but not exclusively, of 4x4 vehicles. These rigidly secured nudge bars cause considerable damage to other vehicles on impact and owing to their rigid metal construction, can cause serious injury to pedestrians hit by vehicles fitted with them.

The applicant is aware of types of nudge bars, e.g. as described in GB 2187142, and GB 1569052, all of which are fixed to the front of a vehicle and which do not have sufficient ability to absorb impact forces during a collision and as a consequence can be hazardous to pedestrians and others. Attempts have been made to absorb some of the impact forces by using nudge bars formed as mouldings of resilient plastics or rubber material with metal inserts as described in the Applicant's earlier patent GB 2236081. However, even with this type of nudge bar it is desired to improve performance and safety and, in addition, such nudge bars are expensive to manufacture.

For lighter duties, it is known to replace the metal framework with a vacuum-formed plastics section, being of a thermo-formed material. This section is then encased or encapsulated in a polyurethane material to give an improved finish to the 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 a nudge bar particularly suitable for use with vehicles and which overcome or at least mitigates one of more of the problems noted above.

The present invention aims to overcome these problems by providing a nudge bar which maintains the aesthetic characteristics of the vehicle to which it is fitted whilst significantly reducing injury to pedestrians resulting from being hit by the vehicle.

Furthermore, damage to other vehicles caused by contact with vehicles fitted with nudge bars of the present invention is also reduced.

Summary of the Invention

According to a first aspect of the present invention there is provided a vehicle nudge bar comprising:- (I) a backing support; (ii) an energy absorbing impact material mounted on said backing support, wherein said energy absorbing material comprises a honeycomb structure, having an impact face; (iii) a moulding of a resilient material formed around said impact face; (iv) a mounting means adapted to mount said backing support to a vehicle.

Using a honeycomb structure provides a more pedestrian-friendly nudge bar than has previously been possible, in the event that the vehicle contacts a pedestrian.

Preferably said honeycomb structure has a variable crush strength across said impact face. By varying the crush strength across the impact face it is possible to provide a nudge bar with different energy absorbing properties for thigh and for head impact.

Preferably said crush strength varies vertically across said impact face.

In an alternative embodiment said crush strength varies horizontally across said impact face instead of or in addition to varying vertically across said impact face.

Preferably said crush strength varies such that the higher crush strength is towards the lowermost edge of the nudge bar in use.

Preferably the variable crush strength of the honeycomb structure arises from different densities of honeycombs. It is possible to make honeycomb structures with a wide variety of crush strengths. These can be attached to the backing support in the desired combination, as specified by a materials specialist.

In an alternative preferred embodiment the varying crush strength of the honeycomb structure arises from sections of the honeycomb structure being formed from different materials.

Preferably said honeycomb structure is formed of at least one of the materials consisting of aluminium, plastic and paper.

Preferably said honeycomb structure is formed from at least one of the materials consisting of polypropylene and polycarbonate.

Preferably said resilient material is a semi-rigid, self-skinning, foamed polyurethane.

Preferably said backing support is formed from at least one of the materials consisting of plastic and metal.

Preferably said backing support is formed from Acrylonitrile Butadiene Styrene (ABS).

Preferably said impact face is curved. This both improves the aesthetic appearance of the product and allows it to be contoured to the front of the vehicle.

Preferably said backing support is curved.

Preferably said mounting means comprises one or more bracket(s) or bracketry system(s) adapted to connect said backing support to the vehicle.

DescriDtion of the DrawinQs The invention will be further described, by way of example, with reference to the accompanying drawings in which: Figure 1 is a front perspective view of a nudge bar according to a first embodiment of the present invention; Figure 2 is a further front perspective view of the nudge bar shown in Figure 1; Figure 3 is a rear perspective view of the nudge bar shown in Figure 2; Figure 4 is a rear perspective view of the nudge bar shown in Figure 1; Figure 5 is an exploded rear perspective view of the nudge bar shown in Figure 1; Figure 6 is an exploded rear perspective view of the nudge bar; Figure 7 is a further exploded rear perspective view of the nudge bar shown in Figure 1; Figure 8 is an exploded front perspective view of the nudge bar shown in Figure 2; Figure 9 is an exploded side view of the nudge bar; Figure 10 is a front perspective view of a backing support; Figure 11 is a further front perspective view of the backing support shown in Figure 10; Figure 12 is a rear perspective view of a backing support; Figure 13 is a front view of a honeycomb structure; Figure 14 is an exploded front perspective view of the backing support and honeycomb structure; Figure 15 is a further exploded front perspective view of the backing support and honeycomb structure; Figure 16 is a front perspective view of the honeycomb structure; Figure 17 is a further front perspective view of the honeycomb structure; Figure 18 is an exploded rear perspective view of the backing support and honeycomb structure; Figure 19 is a further exploded rear perspective view of the backing support and honeycomb structure; Figure 20 is an exploded side perspective view of the backing support and honeycomb structure; Figure 2lis a rear perspective view of the honeycomb structure; Figure 22 is an expbded side view of the backing support and honeycomb structure Figure 23 is a further exploded side view of the backing support and honeycomb structures.

Figures 24 to 28 illustrate embodiments in which the honeycomb structures shown in the shaded regions have a different crush strength to the non-shaded regions.

Description of Preferred Embodiments

The present invention will now be described by way of example only. These examples represent the best ways known to the Applicant of putting the invention into practice, but they are not the only ways this can be done.

The present invention relates to a vehicle nudge bar, and in particular to nudge bars for protecting the fronts vehicles which include 4X4 vehicles and other off road vehicles.

Referring to Figures 1 and 2, these illustrate a front perspective view of a nudge bar according to a first embodiment of the present invention. It will be appreciated that the shape and configuration of the nudge bars illustrated is by way of example only.

Many other shapes of nudge bar are possible using this invention. The nudge bar in this example comprises two vertical elongate bars 11 and two horizontal elongate bars 12 joined together in a rectangular arrangement. The vertical elongate bars 11 extend a short way 10 beyond the end of the horizontal elongate bars to give a gate like arrangement.

The structure of the nudge bars according to this embodiment will now be described in more detail. Referring to Figures 5 to 9 these illustrate exploded front, rear and side perspective views of the nudge bar according to an embodiment of the present invention. The nudge bar comprises an energy absorbing impact material comprising a honeycomb core 16. The honeycomb core 16 is mounted to a backing support 15. The honeycomb core 16 may be formed from any suitable material such as metal, paper or plastics material, for example aluminium, polypropylene or polycarbonate. The honeycomb core is coated or over moulded with a resilient material 17. The coating or moulding of resilient material 17 can thus be formed to give the desired aesthetic result, for example to simulate tubular bars or rods, or to complement the shape of a particular vehicle. The resilient material 17 also has the effect of smoothing out the angular edges of the honeycomb core 16. The resilient material 17 may be a semi-rigid, self-skinning, foamed polyurethane.

Referring to Figures 3 and 4 these illustrate a rear perspective view of the nudge bar as illustrated in Figures 1 and 2 and show the backing support 15. The backing support 15 may be constructed of a rigid metal or plastics material. An example of a suitable plastics material is Acrylonitrile Butadiene Styrene (ABS). An example of a suitable metal is aluminium, steel or stainless steel.

Mounted to the backing support 15 are two or more mounting brackets 13. These brackets may have an aperture 14 to allow for putting a fixing such as a bolt through the support to allow the nudge bar to be mounted on a vehicle. In an alternative embodiment the mounting brackets 13 are formed integrally with the backing support 15. A wide variety of mounting means can be provided, depending on the type of vehicle that the nudge bar is intended to be mounted to. Specially adapted impact absorbing mounting means such as those described in GB2,319,750 (Breed Manufacturing Ltd), the entire text of which is hereby imported by reference, may be used. In this type of fixing the nudge bar is pivotally mounted about shock absorbing units designed to absorb a proportion of the energy of any impact. Other types of impact absorbing mountings may also find use in this application.

Turning now to the honeycomb core, this is an important feature of the invention.

Such cores are known per se and are commercially available from suppliers such as Plascore Inc of Fairview Street, Zeeland, Michigan, USA 49464-0170. they manufacture a wide range of honeycomb from polypropylene and polycarbonate.

Suitable product identification members include PP3O-5 and PP4O-4. these honeycombs can be formed from a wide variety of cell sizes, cell lengths and cell densities. As a result, honeycombs with a wide variety of crush strengths can be obtained, or can be made to order. It has been found that, by combining honeycombs of different crush strengths, it is possible to vary the crush strength around the impact face of the nudge bar. This is particularly advantageous when it comes to maximising pedestrian safety. For example, honeycomb of a lower crush strength can be positioned where head impact might be expected to occur.

Because the honeycomb is mounted onto a substantially rigid backing support, this provides a convenient mechanism to combine honeycombs of various different properties. It will be appreciated that the variation in crush strength can be achieved in a wide number of ways.

Figure 28 illustrates a side view of the honeycomb structure and loading plate wherein the shaded region 113 represents a honeycomb structure which has a different crush strength to the non-shaded region. The honeycomb can be built up in layers starting from the face of the backing support to which the honeycomb is attached. A number of discrete layers could be provided to make up the required depth.

Figures 24 to 27 illustrate front views of the honeycomb structure wherein the shaded regions (IIOA, IIOB, lilA, 111C, 112A, 112B, 112C) represent honeycomb structures which have a different crush strength to the non-shaded regions. Figures 25 and 26 illustrate how in addition, or in the alternative, honeycombs of different crush strengths which can be butted against each other in a side-by-side arrangement such that the crush strength varies around the nudge bar.

Figure 27 illustrates how this variation could be in terms of vertical variation, where the uppermost-in-use part of the nudge bar has a different crush strength to the lowermost-in-use part of the nudge bar illustrated by the shaded regions 11 2A, 112B, 112C. Or it could be a variation across the nudge bar. Figure 24 illustrates how an example of this would be if the nudge bar uprights 11 illustrated in shaded region I lOB, hOC had a different crush strength to the cross-members 12. Or it could be a combination of both. In addition, layers of different crush strength could also be used in any of the above arrangements, as determined by the materials specialist.

It will be appreciated that these are examples only of the general principle that the crush strength may vary around the nudge bar as determined necessary or advantageous by the materials specialist.

It follows therefore that the honeycomb core 16 may have the same crush strength throughout the nudge bar. However, in an alternative embodiment the honeycomb core 16 has different crush strengths at the top 18 of the nudge bar to the bottom 19 of the nudge bar, or at the left and right hand sides or the nudge bar. In one embodiment the variation in the crush strength of the honeycomb core 16 results from different sections of the honeycomb core 16 being formed from different materials. In another embodiment the variation in the crush strength of the honeycomb core 16 results from the honeycombs 20 being formed of different densities and/or different cell sizes. In yet another embodiment the variation in the crush strength of the honeycomb core results from a combination of these factors, i.e. both a second material is employed and the densities and or cell sizes of the honeycombs 20 are varied.

The substantially rigid backing support 15 advantageously has perforations (not shown) extending through the body of the support and which allow air from compressed cells to flow out, in the event of an impact. It is important for the proper performance of these nudge bars that, in the event of a significant impact, the honeycomb cells can collapse in the way they were designed to do. Since the moulding of resilient material 17 over the impact face of the honeycomb structure is general not vapour permeable, the only escape route for compresses gases within the collapsing honeycomb is through the backing support. If multiple layers of honeycomb are used it may also be advantageous to provide a perforated sheet of metal or plastics materials to separate each adjacent layer.

As a consequence of this, it will be appreciated from Figure 4 for example, that the moulding of resilient material extends around the so-called impact face only, and does not extend over the backing support. This arrangement is preferred unless there is a perceived advantage in having the resilient material cover the backing support and any perforations therein. This could, for example, stiffen the honeycomb over and above its design characteristics with open-ended cells.

Claims

Claims: 1. A vehicle nudge bar comprising:- (i) a backing support; (ii)

an energy absorbing impact material mounted on said backing support, wherein said energy absorbing material comprises a honeycomb structure, having an impact face; (iii) a moulding of a resilient material formed around said impact face; (iv) a mounting means adapted to mount said backing support to a vehicle.

2. A vehicle nudge bar as claimed in Claim I wherein said honeycomb structure has a variable crush strength across said impact face.

3. A vehicle nudge bar as claimed in Claim 2 wherein said crush strength varies vertically across said impact face.

4. A vehicle nudge bar as claimed in Claim 2 wherein said crush strength varies horizontally across said impact face.

5. A vehicle nudge bar as claimed in any of Claims 2 or 3 inclusive wherein said crush strength varies such that the higher crush strength is towards the lowermost edge of the nudge bar in use.

6. A vehicle nudge bar as claimed in any of Claims 2 to 5 inclusive wherein the variable crush strength of the honeycomb structure arises from different densities of honeycombs.

7. A vehicle nudge bar as claimed in any of Claims 2 to 5 inclusive wherein the varying crush strength of the honeycomb structure arises from sections of the honeycomb structure being formed from different materials.

8. A vehicle nudge bar as claimed in any preceding claim wherein said honeycomb structure is formed of at least one of the materials consisting of aluminium, plastic and paper.

9. A vehicle nudge bar as claimed in any preceding claim wherein said honeycomb structure is formed from at least one of the materials consisting of polypropylene and polycarbonate.

10. A vehicle nudge bar as claimed in any preceding claim wherein said resilient material is a semi-rigid, self-skinning, foamed polyurethane.

11. A vehicle nudge bar as claimed in any preceding claim wherein said backing support is formed from at least one of the materials consisting of plastic and metal.

12. A vehicle nudge bar as claimed in any preceding claim wherein said backing support is formed from Acrylonitrile Butadiene Styrene (ABS).

13. A vehicle nudge bar as claimed in any preceding claim wherein said impact face is curved.

14. A vehicle nudge bar as claimed in any preceding claim wherein said backing support is curved.

15. A vehicle nudge bar as claimed in any preceding claim wherein said mounting means comprises one or more bracket(s) or bracketry system(s) adapted to connect said backing support to the vehicle.

16. A vehicle nudge bar substantially as herein described with reference to and as illustrated in any combination of the accompanying drawings.