Air Mattress

Abstract

An air mattress includes two covers each with a series of longitudinally extending fabric strips secured to the respective inner faces. Opposite corresponding strips are interconnected by partitions which may be continuous with spaced apertures or may be discontinuous.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to air mattresses.

2. Description of the Prior Art

With air mattresses, and more particularly those used as underlays in beds, the aim is to give the main faces the form of wave crests and troughs. It is this quilted effect which preserves the typical character of the mattress.

To achieve this quilted effect, low partitions, preferably I-shaped in section, are cemented to the interior of the two main faces of the mattress. These partitions are spaced apart and arranged in rows running longitudinally of the mattress. As the mattress is inflated, those portions of the main faces which lie between the various portions curve outwards, whereas the immediately adjacent parts of the said faces do not expand at all. The unexpanded parts thus form the wave troughs, the wave crests being formed by the parts blown up during inflation.

Points of overstress arise where the outer faces change from trough to crest. The forces arising at this change are so high that they tend to detach the horizontal flanges of the partitions from the interior of the main faces, especially when the parts are only cemented together. Once this process of detachment is started, it continues until, within a very short space of time, the partitions become completely detached from the faces of the mattress. The result eventually is that the quilted effect is entirely lost and the overall shape of the mattress becomes wholly unacceptable.

An object of the invention is therefore to provide a mattress to ensure at all times a firm hold, however high the interior pressure, between the members forming the connections between the mattress faces, by which the quilted effect is produced, so that the undulations are preserved even when the mattress has been in use for a long time.

SUMMARY OF THE INVENTION

According to the present invention there is provided an air mattress comprising a first cover sheet, a second cover sheet lying generally parallel to the first cover sheet, a first series of strips of material extending longitudinally of the mattress, spaced transversely of the mattress and secured to the first cover, a second series of strips of material extending longitudinally of the mattress, spaced transversely of the mattress and secured to the second cover, and means defining partitions each extending between a respective pair of said opposed strips of said first and second series, each said partition being interrupted along its length by spaced elliptical apertures of a size such that on inflation of the mattress the configuration of both cover sheets is affected.

BRIEF DESCRIPTION OF THE DRAWINGS

Two embodiments of a mattress in accordance with the invention will now be described by way of example, with reference to the accompanying diagrammatic drawings, in which:

FIG. 1 is a plan of a portion of one example of the mattress here proposed;

FIG. 2 is a section along the line II--II of FIG. 1;

FIG. 3 is an isometric view to an enlarged scale, showing a portion of two strips and interposed partition sections;

FIG. 4 is a fragmentary plan of another embodiment of the mattress;

FIG. 5 is a section along the line V--V in FIG. 4, and

FIG. 6 is an isometric view, to an enlarged scale, showing a portion of two strips and an interposed partition containing cutouts, seen in FIG. 4.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Two main faces 1 and 2 (first and second cover sheets) of the mattress which may be made of rubberized fabric and are joined all round to side walls 3 together provide a generally flat formation when inflated. As can be seen from FIGS. 1 and 2, the two faces 1 and 2 exhibit the typical quilted effect, with wave crests and troughs alternating, so as to present purely externally the appearance of a typical air mattress. This quilted effect is obtained by means of strips of material (first and second series) 4 and 5, which run longitudinally of the mattress and are joined to the two faces 1 and 2, for example by cementing. As can be seen from FIG. 1, these strips 4 and 5 are spaced apart transversely across the mattress.

Partitions 6, of U-shaped cross-section, are joined, for example by sewing or cementing, to these strips 4 and 5. The partitions 6 are spaced apart along the length of the strips 4 and 5.

FIG. 2 shows how, when the mattress is inflated, the strips 4 anf 5 and hence also the mattress faces 1 and 2 curve outwards in the vicinity of the gaps, whereas the length between the strips 4 and 5 remains unchanged in the vicinity of the partitions 6, since the forces arising from inflation are absorbed by the partitions 6, which are inelastic.

The joining, on the one hand, of the partitions 6 to the strips 4 and 5 and, on the other hand, of these strips to the faces 1 and 2, virtually makes it impossible for the partitions 6 to come apart from the strips 4 and 5 at the points of high stress. The quilted effect will thus be retained at all times, even if the maximum permissible pressure be exceeded.

In the embodiment illustrated in FIGS. 4 to 6, strips of material 7 and 8 (corresponding to the strips 4 and 5 in the first embodiment), secured to the mattress faces 1 and 2. These strips 7 and 8, considered in cross-section, are continued as a partition 9, which thus forms with them a single homogeneous unit. The two strips 7 and 8 and the partition 9 consequently combine to form a U-shaped cross section.

Apertures 10, are provided in the partition 9 at intervals along the length of the partition. In the embodiment illustrated, these cutouts lie symmetrically about the longitudinal centre line X--X of the partition 9 and are elliptical in shape; it is immaterial, however, whether they be round or oval.

A continuous additional strip 11 or 12 is joined to each partition 9 and is flush with the associated strip 7 or 8. These two strips 11 and 12 serve to strengthen the joint between the mattress faces 1 and 2 and the interposed connecting members. During inflation, as can be seen from FIG. 6, those parts of the partition 9, strips 7/11 and 8/12 and mattress faces 1 and 2 which lie opposite the apertures 10 are expanded and produce wave crests at those points, the wave troughs being formed between the apertures 10.

A feature common to both embodiments is that the apertures 10 or the gaps lying between the partitions 6 are distributed checkerboard-fashion over the mattress as a whole.

The embodiments herein proposed make it virtually impossible for the connecting members that provide the quilted effect to be detached from the main faces (cover sheets) of the mattress, as has been clearly demonstrated by experiment.

Moreover, the mattress embodying the invention can be produced simply and cheaply.

Claims

We claim:

1. An air mattress comprising

a first cover sheet,

a second cover sheet lying generally parallel to the first cover sheet,

a first series of strips of material extending longitudinally of the mattress, spaced transversely of the mattress and secured to the first cover,

a second series of strips of material extending longitudinally of the mattress, spaced transversely of the mattress and secured to the second cover, and

means defining partitions each extending between a respective pair of said opposed strips of said first and second series, each said partition being interrupted along its length by spaced elliptical apertures of a size such that on inflation of the mattress the configuration of both cover sheets is affected.

2. A mattress according to claim 1, wherein the strips of both series are joined to the respective cover sheet by adhesive.

3. A mattress according to claim 1, wherein each partition is integral with the respective opposed strips.

4. A mattress according to claim 3, comprising additional strips each contiguous with one of the strips of the first and second series, secured to a respective said cover sheet and to one of the partitions.

5. A mattress according to claim 1, wherein each aperture lies symmetrically about the longitudinal centre line of the partition.

6. A mattress according to claim 1, in which the apertures of the partitions are distributed checkerboard-fashion over the mattress as a whole.