WO2006046034A1

WO2006046034A1 - Structural element for a vehicle

Info

Publication number: WO2006046034A1
Application number: PCT/GB2005/004135
Authority: WO
Inventors: Robert Clive Mullins
Original assignee: Elan House Limited
Priority date: 2004-10-25
Filing date: 2005-10-25
Publication date: 2006-05-04
Also published as: GB0423679D0; GB2419330A

Abstract

A structural element (20) for a vehicle is disclosed. The element comprises an at least partially transparent body (22), having a three-dimensional array of interconnected chambers arranged to allow light to pass through the body so as to provide at least partial visibility through the element to an occupant of the vehicle when the structural element is mounted in the vehicle. An example of a structural element to which the invention may be applied is a pillar for a car.

Description

Structural element for a vehicle

The present invention relates to a structural element for a vehicle.

Vehicles, in particular those with enclosed passenger / driver cabins (for example cars), typically have structural features such as pillars or uprights which obstruct the vehicle driver's view from the vehicle. Although modern vehicle design attempts to minimise the visual obstruction caused by such structural features, these attempts are limited by structural and safety considerations. The driver's field of view is therefore generally incomplete, to the detriment of driver and passenger safety.

The present invention seeks to alleviate some of these problems.

Accordingly, in a first aspect of the invention, there is provided a structural element for a vehicle, wherein the element comprises an at least partially transparent body, the body comprising a three-dimensional array of interconnected chambers arranged to allow light to pass through the body so as to provide at least partial visibility through the element to an occupant of the vehicle when the structural element is mounted in the vehicle.

The occupant is preferably the operator of the vehicle, the chambers being arranged so as to provide partial visibility through the element to the operator when the structural element is mounted in the vehicle and the operator is positioned for operating the vehicle.

In this way, the vehicle operator's view can be enhanced, which can lead to greater visual and situational awareness and improved safety.

In a further aspect of the invention, there is provided a method of manufacturing a structural element for a vehicle, wherein the element comprises an at least partially transparent body, the body comprising a three- dimensional array of interconnected chambers arranged to allow light to pass through the body so as to provide at least partial visibility through the element to an occupant of the vehicle when the structural element is mounted in the vehicle, the method comprising forming the body of a material using a layerwise process including selectively fusing particles of the material to a previous layer to form a subsequent layer. Preferred features of the present invention will now be described, purely by way of example, with reference to the accompanying drawings, in which:-

Figure 1 is a schematic side view of a car; Figure 2 is a schematic cross-section of a partially transparent pillar in accordance with an embodiment of the present invention;

Figures 3A to 3G show examples of structures for use in the partially transparent pillar;

Figures 4 and 5 are schematic cross-sections of partially transparent pillars in accordance with alternative embodiments of the present invention; and

Figure 6 is a schematic of a device for use in a selective laser remelting process.

Embodiments of the present invention seek to provide the driver / rider and passengers of a vehicle with an improved view of the surroundings and driving conditions around the vehicle by enhancing the view normally available. This is achieved by making visually obstructive structural features partially transparent. In this way, safety can be improved for those in the vehicle as well as for other traffic participants. The present invention will be described using the example of a car, though it may also be applied to other types of vehicles.

Figure 1 is a schematic view of a car 10. Cars are commonly designed with three main sets of pillars for supporting the roof: A pair of "A"-pillars either side of the windscreen, a pair of "B"-pillars between the side windows and a pair of "Capillars at the rear of the vehicle.

The driver's view out of the front of the car is typically obstructed mainly by the "A"-pillars. To see out of the back of the car, rather than turning around, the driver usually makes use of a combination of wing mirrors and a central rear view mirror. Though the rear view mirrors provide a view to the rear of the car, this can be limited, and in the case of the central rear view mirror, the view reflected usually also includes the "Capillars. Both the driver's front view and the view presented by the rear view mirror (or if the driver turns around) are therefore incomplete. In embodiments of invention, some or all of the "A", "B" and "C" pillars are replaced by at least partially transparent pillars which serve to complete the driver's view of the vehicle surroundings. The partially transparent pillars comprise a three-dimensional mesh-like or honeycomb structure which is filled or coated with glass, polycarbonate or composite see-through material.

The partially transparent pillar is preferably designed to provide sufficient structural strength to fulfil structural and safety requirements, and is preferably at least as strong as the conventional pillar it replaces. The pillar preferably provides sufficient visibility so that major objects and obstructions and movement (such as vehicles, cyclists and pedestrians), which would otherwise be obscured, can be perceived even if the view provided is not as detailed or complete as that provided through the windscreen and side windows. Preferably, at least 70% visibility through the structure is provided in at least the driver's principal viewing direction. The pillars can be attached to the chassis and roof by, for example, welding or glue bonding.

A variety of pillar shapes may be provided, for example, round, triangular, square or oblong columns, as well as more complex shapes. Although the pillars can be provided in a similar or substantially identical shape to the pillars being replaced, the strength and enhanced visibility may allow the design of the pillar to be varied more freely, and thus can provide greater freedom to vehicle designers.

Figure 2 shows a schematic cross-sectional view of an "A" pillar in accordance with an embodiment of the present invention.

The pillar comprises a body 22 of a three-dimensional mesh or honeycomb-like structure. The structure is closed at the bottom and top by solid base and top portions 28 and 26 respectively. Transparent layers 24 on the outer and inner sides of the body 22 seal the body and provide a smooth, transparent surface. The driver's viewing direction through the pillar is indicated by arrow A. The pillar body has a fine three-dimensional lattice or mesh structure.

The mesh or lattice structure consists of interconnected strands of a sufficiently strong material (typically metal), which form a plurality of small (at least optically) interconnected chambers. The chambers may, for example, be octahedral or diamond-shaped. A variety of other suitable shapes may also be used, for example tetrahedra, dodecahedra, icosahedra or cubes. The metal strands thus typically form the edges of the polyhedra, with the term "chambers" here preferably referring to the interior spaces defined by those edges. Typically, the faces of the polyhedra forming the chambers are open to the adjacent chambers, thus (optically) connecting the chambers. Any suitable chamber shape may be used and would typically be selected to provide an adequate balance between the structural strength and visibility provided. Different chamber shapes may also be combined in the same structure.

The size of chambers is preferably also selected based on strength and visibility provided by the resulting structure. In the example of diamond / octahedral chamber shapes, chambers with individual side lengths of between 5mm and 20mm are preferred. Preferred examples have side lengths between 10 and 15 mm, preferably about 12 to 13mm, for example approximately 12.5mm. Equivalent chamber sizes are preferred for other chamber shapes.

The interconnected chambers are arranged to provide straight-line paths through which light may pass through the body in at least the driver's principal viewing direction, but preferably also allow some visibility when viewed from different angles, though, depending on the chamber structure, this may be less than the visibility afforded in the principal viewing direction. Thus, direct lines of sight are provided through the body at a plurality of different viewing angles. The different viewing angles span a range of angles having an extent of at least 15 degrees, preferably at least 30 degrees and more preferably at least 45 or 60 or 90 degrees, thus affording the driver an improved view from different positions. The different viewing angles are possible due to the three-dimensional lattice structure. The lines of sight typically pass through at least 3 chambers, preferably at least 5 chambers, more preferably at least 10 or 15 chambers.

The shape and/or orientation of chambers may vary according to the shape of the pillar and/or the driver's (expected) principal viewing direction. For example, in a pillar as shown in Figure 2, the inclination of the chambers at the bottom of the pillar may be different from the inclination of chambers at the top of the pillar so as to provide the best view through the pillar at each location, given a typical driver height and position. Figures 3A to 3G show examples of structures for use in the partially transparent pillar.

Figure 3A shows a structure having diamond-shaped chambers. Figures 3B, 3C and 3D respectively show top, front and side views of the structure of Figure 3A.

Figures 3E and 3F show perspective views of a similar but slightly denser structure, and Figure 3G shows a cross-section through such a structure.

To provide increased strength, selected connection points of the strands forming the chambers may have slightly increased thickness compared to the strands themselves.

Figures 4 and 5 show alternative embodiments of the pillar in which reinforcing beams are provided within the structure of the body 22. In Figure 5, several horizontal reinforcing beams 32 are provided. To ensure that these do not significantly obstruct the view through the pillar, they are preferably small in diameter and arranged parallel to the driver's typical viewing direction. The reinforcing beams may themselves be made of a transparent material (such as that used for the transparent outer surfaces) to further reduce the impact on visibility. In Figure 5, reinforcing beams 34 are arranged in a zig- zag fashion, again substantially parallel to the driver's viewing direction. Alternatively, vertical (preferably transparent) supporting beams may also be used.

As mentioned above, instead of (or in addition to) being coated, the body may be filled with a transparent material such as glass, light-weight optically clear ceramic or plastic polycarbonate. Some, all or substantially all of the chambers may be filled in this way. The reinforcing beams mentioned above may be provided by filling some chambers with transparent material.

This can improve the strength and rigidity of the pillar. In addition, the optically clear filling material can serve to guide the light passing through the body in certain directions (depending on the structure of the mesh or lattice), thus providing a plurality of (intersecting) virtual light pipes running In those directions. This effect can be enhanced by making the mesh or lattice using a reflective material, or coating the interconnected strands forming the lattice with a reflective material.

<> Where, as in the embodiments described with reference to Figures 2, 4 and 5, transparent layers or skins 24 are provided on the body 22, a heater may be provided in or adjacent the body, for example at the base 28, or connected to the body, to prevent or reduce condensation. The transparent layers may be made of an optically clear ceramic material or microglass.

Coating of an anti-reflective nature can be applied to the transparent outer surfaces of the element to reduce the effect of bright sunlight or other vehicles' headlights. The anti-reflective coating may comprise indium tin oxide, gold, or platinum, which may be applied to the transparent outside surfaces of the pillar by sputtering.

The chamber structure of the body 22 can be formed by casting or moulding or by some other suitable method. In a preferred embodiment, the structure is manufactured using a technique known as selective laser remelting. This technique is similar to stereo lithography methods using laser- hardening of liquid resins in that the structure is built up layer-wise. This is achieved by selectively remelting portions of a layer of fine metal powder using a laser. The process is illustrated in Figure 6.

The process uses a laser remelting device 70 comprising a building chamber 72 filled with an inert gas, in which a three-dimensional structure 92 is built up on a moveable platform 74. The device comprises a laser 82, and a scanner 84 for directing laser beam 86 through laser window 88 onto a central area 94 of the building chamber 72. The scanner 84 moves the laser beam across area 94 in two dimensions.

In use, a quantity of metal powder 90 is added to the building chamber 72. Levelling mechanism 76 ensures that a level layer of metal powder is provided over the central area 94 above moveable platform 74. The laser then traces a shape in the layer of powder corresponding to a layer of the structure being built, thereby melting portions of the powder. The melted portions then cool and solidify. A solid layer of the structure is thereby produced. The moveable platform 74 is then lowered, and a new layer of powder is applied to central area 94, from which the next layer of the structure is then made.

The above-described process is suitable for producing intricate metal structures of the kind used in the partially transparent pillars described herein. The metal structures generated are essentially homogeneous, which can enhance the strength of the structures.

The process can essentially form any lattice or matrix shape. Solid shapes, such as reinforcing beams (as described, for example, with reference to Figures 4 and 5 above) can also be formed within (and integrally with) the lattice structure of the body.

Many different type of metals and ceramic composites can be used in this process, and the process allows for the mixing of different materials.

Typically, metals are used, for example, aluminium, titanium or steel though other materials may also be suitable. In preferred examples, the material used is selected based on criteria such as weight and strength.

The details of the design of the structure are selected to give the desired optical properties.

It will be understood that the present invention has been described above purely by way of example, and modification of detail can be made within the scope of the invention.

For example, although in Figure 1 , a car is shown in which the "A", "B" and "C" pillars are transparent pillars as described herein, transparent pillars may be used for selected pillars only, for example only for the "A" pillars. Aspects of the system may be applied to a wide range of different types of vehicles, including, for example, cars or vans, as well as aircraft cockpits, driver cabins on trains, and the like. A similar structure as described herein could also be used in motorcycle helmets (for example, at the sides) to give improved peripheral vision whilst maintaining the strength of the helmet.

Claims

1. A structural element for a vehicle, wherein the element comprises an at least partially transparent body, the body comprising a three- dimensional array of interconnected chambers arranged to allow light to pass through the body so as to provide at least partial visibility through the element to an occupant of the vehicle when the structural element is mounted in the vehicle.

2. A structural element according to Claim 1 , wherein the body is made of a substantially homogeneous material.

3. A structural element according to Claim 1 or 2, wherein the occupant is the operator of the vehicle, the chambers being arranged so as to provide at least partial visibility through the element to the operator when the structural element is mounted in the vehicle and the operator is positioned for operating the vehicle.

4. A structural element according to any of the preceding claims, wherein the chambers are in the shape of regular polyhedra.

5. A structural element according to any of the preceding claims, wherein the chambers are formed by a plurality of sides, the sides having lengths of between 5mm and 20mm, preferably between 10 and 15mm.

6. A structural element according to any of the preceding claims, wherein the body is formed by a process involving selective fusing of particles.

7. A structural element according to any of the preceding claims, wherein the body is made by a selective laser remelting process.

8. A structural element according to any of the preceding claims, wherein at least some of the chambers are filled with a transparent material.

9. A structural element according to any of the preceding claims, wherein the body is filled with a transparent material.

10. A structural element according to any of the preceding claims, wherein a layer of transparent material is provided on an outer side of the element.

11. A structural element according to Claim 10, further comprising an anti-reflective or anti-glare coating on the transparent layer.

12. A structural element according to any of the preceding claims, further comprising a reinforcing beam extending through the structural element.

13. A structural element according to Claim 10, wherein the reinforcing beam is made of a transparent material.

14. A structural element according to any of the preceding claims, wherein the chambers are aligned to provide direct lines of sight through the body.

15. A structural element according to Claim 14, wherein the lines of sight pass through at least 5 and preferably at least 10 chambers.

16. A structural element according to any of the preceding claims, wherein the chambers are aligned to provide direct lines of sight through the body at a plurality of different viewing angles.

17. A structural element according to Claim 16, wherein the plurality of different viewing angles span a range of angles having an extent of at least 30 degrees, preferably at least 45 degrees, more preferably at least 60 or 90 degrees.

18. A structural element according to any of the preceding claims, wherein the body is formed of a three-dimensional lattice of interconnected elongate members, the members defining the chambers.

19. A structural element according to any of the preceding claims, wherein the element is in the form of a pillar.

20. A vehicle comprising one or more structural elements as claimed in any of the preceding claims.

21. A method of manufacturing a structural element for a vehicle, wherein the element comprises an at least partially transparent body, the body comprising a three-dimensional array of interconnected chambers arranged to allow light to pass through the body so as to provide at least partial visibility through the element to an occupant of the vehicle when the structural element is mounted in the vehicle, the method comprising forming the body of a material using a layerwise process including selectively fusing particles of the material to a previous layer to form a subsequent layer.

22. A method according to Claim 21 , comprising defining the body as a stack of cross-sectional planes in a given dimension, and wherein the layers formed correspond to the cross-sectional planes.

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