GB2048663A - Headrest for vehicle seats - Google Patents

Abstract

A headrest (or backrest) in which a framework (1) for attachment to a vehicle seat supports a net-like structure (3), the frame (1) and the net members (3) being cushioned against impact by the user's head. The net consists of a core of threads or strings (4), e.g. of polyamid, formed by a moulding process, e.g. spraying, in which they are attached to the metal frame (1), and the entire assembly of frame and strings (4) is then placed in a second mould into which a synthetic plastics material, e.g. polyurethane, is injected and foamed to provide the cushioning material (2) and elastic casings (3) on the strings (4). Preferably, the cushioning (3) is asymmetrically formed about the net-forming threads (4), with the greatest thickness of cushioning being deposited at that side of the thread intended to take any impact from the user's head. <IMAGE>

Description

SPECIFICATION Headrest for vehicle seats The present invention relates to headrests for vehicle seats having a cushioned frame and a net-like part arranged on the frame.

Headrests for vehicles are provided with a netting part, because a net provides, on the one hand, relatively favourable cushioning qualities in case of impact by the head of a person occupying the seat and, on the other hand, it gives the desired transparency so that the driver of the vehicle has no unnecessary obstruction to his view directly behind or through the rear-view mirror.

Such netting headrests have not so far found their way into practical use. This can be ascribed to the difficulties in production, particularly with regard to fastening the net on to a suitable frame in a suitable position and under suitable tension. Moreover, in the case of known netting headrests there is a need for improvement, especially with respect to impact on the head of a person. It has become apparent that a disadvantage of known netting headrests is that they meet a striking head mainly with a flat surface, simply because the individual strings of the net are in straight lines when stretched.

The present invention provides an improved construction of netting headrests, particularly desirable for anatomical reasons.

According to the present invention a headrest for vehicle seats having a cushioned frame and a netlike structure is characterised in that the net connected with the frame consists of a core formed by strings or threads respectively with casings of elastic man-made material converted into foam.

By this division of the net into two constituent parts, the desirable firmness results from the core structure. The elasticity of the net, however, is mainly achieved by the casing, which can also be made into a shape independent of the core in such a way that anatomical considerations which are required in the construction of head rests can be fulfilled.

In the construction of a headrest according to the invention the casing enclosing the strings or threads may be shaped level in the direction of impact from a head; the term level including not merely a flat surface, but, for example, a dome shape, preferably arranged to be convex in the direction of impact.

Finally, the casings of the threads or strings can be constructed in such away that they taper in crosssection and thus have, preferably, a triangular or trapezoidal shape.

In this way, a large impact surface is made available for the head, without obstructing the view through the netting headrest, or not obstructing the view more than is necessary.

The strings of the netting are so arranged that the cores within the strings are displaced rearwards in relation to the head-impacting surface, thus preventing injury even when the head strikes the headrest with such force that the casing is destroyed.

In a preferred form of construction of the headrest, the strings or threads of the core run in straight lines so that they can be given a desired tension between the fastenings of the frame. It is to be understood that the casing enclosing the core string or thread does not need to be arranged in a straight line, nor with a straight surface on the outside. On the contr ary, a kind of casing is preferred which is made subj ect to torsional stress and dome-shaped. Neverthel ess, however, a casing constructed in this way will still have a core thread that can be stretched in a straight line.

In order to increase the clear view still further, the frame of the netting headrest need not be construc ted in the form of a complete enclosure. Instead, a U-shaped frame can be used, in which the side-ends are connected by means of a strap constructed in a manner similar to that of the encased netting strings.

The individual core threads or strings can be made from single or multiple threads. Polyamid appears to be a particularly suitable material for these threads.

In a preferred construction for a netting headrest according to the invention, the core threads of the net are secured by a spraying process on to the met allic bars of a frame. In this way the separate tying or otherwise connecting of each core thread to the frame is avoided. After this operation, the encasem ent of the core threads and, if required, the strap can then be carried out in one or more operations.

Polyurethane is found to be a particularly suitable material for the formation of the cushioning round the frame and the casing of the core threads, and this material is made into foam by means of a foaming material. It is preferred to use an injection process to produce the netting headrest and in carrying out this method the central area of the netting is preferably chosen as the injection point. If polyurethane is inje cted and foamed out from this spot, the area adjac ent the injection point will have greater strength as compared with those more distant areas and this is particularly advantageous in a headrest according to this invention.

It will be realised that other seats can also be cons tructed with a headrest or with a backrest made in accordance with the present invention.

Headrests embodying the present invention will now be described, by way of example, with refere nce to the accompanying drawing, in which, Figure 1 is a view of a netting headrest illustrating the method of construction of the invention, Figures 2 and 3 show side views of variations in the construction of netting head rests, Figure 4 illustrates a U-shaped headrest, Figure 5 shows a diametrical cross-section thro ugh one of the netting strings or threads of the nett ing area of a headrest as shown in Figures 1 to 4, and, Figure 6 shows on an enlarged scale the central area ofthe netting area.

In the Figures, a metallic member 1 is provided, which can be fixed to the seat of a vehicle, for exam ple, at two points, as in the case of Figure 1, or at a The drawings originally filed were informal and the print here reproduced is taken from a later filed formal copy.

single point, as in the case of Figure 4. The member 1 is provided with an enclosing casing of a cushioning material 2, which consists preferably of a polyurethane foam. A net is secured between the frame parts, the net consisting of single strings 3.

The particular manner in which the netting parts, or strings, 3 are connected with the cushioned casing 2 or the member 1 is not shown in the figures, because the precise method for the fastening is not essential for the understanding of the present invention, and it is to be understood that any suitable fixing means may be employed. However it is essential for the present invention that the individual parts of the netting should be constructed as described below in relation to Figure 5.

Figure 5 shows an example of a preferred method of construction for the strings or threads 3 of the netting. Thus, for example, these parts have a trapezoid cross-section, in which the forward-facing surface, which may be contacted by the head, is represented as the upper part of the trapezoid. Towards the rear (shown in Figure 5 as the bottom part) is embedded a core thread 4, which, for example, is made of polyamid.

Figures 2 and 3 clarify the shape of the netting area within the netting headrest according to the invention, the shape shown in Figure 3, especially, providing the anatomically most favourable impact surface for the head.

Figure 6 shows schematically the centre part of the netting area shown in Figure 1 and Figure 4, wherebb the injection of the casing material is applied through a channel 5 and then through four injection ducts to the main netting area, three of the ducts being shown in the Figure.

Thus, in accordance with a preferred process for manufacture of the netting headrest, initially the member 1 is inserted into a mould and polyamid is sprayed into the mould to form the core strings of the future net. During this spraying step, the netting threads 4 enclose the member 1 to form the desired straight-line shape. After having been taken out of the mould, the enclosed member i with its net of core threads 4 is placed into another mould. Into this second mould, as noted above in connection with Figure 6, polyurethane is injected and foamed out from the central area of the net. Thus, in this final moulding operation a netting headrest is made as in Figures 1 to 4, in which the parts 3 forming the net are connected integrally with the cushioned casing 2 of the frame formed by the member 1.

Claims (14)

1. Headrest for vehicle seats having a cushioned frame and a net-like structure arranged on the frame, characterised in that the net connected with the frame consists of a core formed by threads or strings respectively with casings of elastic man-made material converted to foam.

2. Headrest according to Claim 1, further characterised in that the casing enclosing the core threads or core strings has a flat or domed configuration.

3. Headrest according to Claim 1 or Claim 2, furt her characterised in that the cross-section of the cas ing of the core threads or core strings is of tapering shape.

4. headrest according to any one of claims 1 to 3, further characterised in that the casing of the core threads or core strings has in cross-section a triangular or trapezoid shape.

5. Headrest according to any one of claims 1 to 4, further characterised in that the core threads or core strings in the net-forming casings are displaced rearwards relative to the impact surface for the user's head within the casings.

6. Headrest according to any one of claims 1 to 5, further characterised in that the core strings or core threads are under tension and are each directed in a straight line.

7. Headrest according to any one of the preceding claims, further characterised in that the frame is U-shaped and the ends of the sides of the U-shape are connected by a member which is constructed in a similar way to the casing as set out in any one of the claims 2 to 5.

8. Headrest according to any one of the preceding claims, further characterised in that the frame is enclosed in cushioning material and the net has a convex configuration relative to the impact surface provided to receive the user's head.

9. Headrest according to any one of the preceding claims, further characterised in that the core th reads or core strings each consist of a single or multiple polyamid thread.

10. Headrest according to any one of the preceding claims, further characterised in that the core threads or core strings are produced by a mould/spray process before being encased in an elastic synthetic material.

11. Headrest according to any one of the preceding claims, further characterised in that the cushioning enclosing the frame and the casing of the core strings or threads respectively consists of polyurethane foam.

12. Headrest according to any one of the preceding claims, further characterised in that the cushioning encasing the frame and the casing of the core threads or core strings respectively is formed by only one moulding process.

13. Headrest according to Claim 12, further characterised in that the injection points for the polyurethane moulding process are provided at the cnetre of the net-like structure.

14. Headrest having a cushioned frame and a net-like structure arranged on the frame constructed and arranged substantially as described with referenice to Figures 1,2, 5 and 6; 1,3,5 and 6; or 4, 5, and 6, of the accompanying drawings.