Mattress with different firmness zones

Abstract

A mattress has a perimeter rail having a head end, a foot end, and two sides, each having an inner surface, and at least two substantially parallel rectilinear sections. Each section comprises an array of springs whose tension is selected to provide a predetermined firmness for that section. Each adjacent pair of sections is urged into a spaced-apart relationship by a spacing means, where each spacing means comprises a flexible spacer. The flexible spacer restricts or substantially eliminates the translation of movements between the sections of the mattress, while avoiding the use of uncomfortable separation means.

Claims

1. A mattress comprising: an upper resilient layer; a lower resilient layer; a perimeter rail located between the upper and lower resilient layers and having a head end and a foot end, the perimeter rail comprising first and second side rails each having a width and arranged between the head end and the foot end; two support sections located within the perimeter rail between the head end and the foot end; and a flexible spacer positioned between the two support sections and retained along its length between the upper and lower resilient layers, a first end of the flexible spacer retained at the head end of the perimeter rail and a second end of the flexible spacer retained at the foot end of the perimeter rail, wherein a width of the flexible spacer is at most half of the width of the side rails.

2. The mattress of claim 1, wherein a width of the flexible spacer is selected to restrict translation of movement between adjacent support sections.

3. The mattress of claim 1, wherein the two support sections are aligned substantially parallel to each other in a horizontally adjacent relationship.

4. The mattress of claim 1, wherein the two support sections each comprise an array of springs.

5. The mattress of claim 4, wherein each of the array of springs provide a respective predetermined firmness for each of the two support sections.

6. The mattress of claim 4, wherein each of the array of springs comprise a plurality of rows of individual springs each having an associated height.

7. The mattress of claim 6, wherein the height of one or more of the rows of springs in each of the spring arrays is greater than a height of the perimeter rail.

8. The mattress of claim 6, wherein the associated height of one or more of the rows of springs in each of the spring arrays is greater than a height of the flexible spacer.

9. The mattress of claim 4, wherein each of the array of springs comprises springs of a plurality of different tensions.

10. The mattress of claim 4, wherein the flexible spacer is attached to each of the array of springs of the two support sections along at least a portion of a length of the flexible spacer.

11. The mattress of claim 1, wherein each of the two support sections are attached to an inner surface of the head end of the perimeter rail and to an inner surface of the foot end of the perimeter rail.

12. The mattress of claim 1, wherein the each of the two support sections are attached at respective lower faces to the lower resilient layer and at respective upper faces to the upper resilient layer.

13. The mattress of claim 1, wherein the perimeter rail is attached at a lower face to the lower resilient layer and at an upper face to the upper resilient layer.

14. The mattress of claim 1, wherein a height of the flexible spacer and a height of the perimeter rail are the same.

15. The mattress of claim 1, wherein a height of the flexible spacer and a height of the perimeter rail are different.

16. The mattress of claim 1, wherein at least one of the upper resilient layer and the lower resilient layer are made of foam.

17. The mattress of claim 1, wherein at least one of the upper resilient layer and the lower resilient layer are made of dense fibers.

18. The mattress of claim 1, further comprising: an additional support section located within the perimeter rail between the head end and the foot end; and an additional flexible spacer located between the additional support section and one of the two support sections, an end of the additional flexible spacer retained at the flexible spacer and an opposite of the additional flexible spacer retained at a side rail of the perimeter rail.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The embodiments of the present invention will now be described by reference to the following figures, in which:

(2) FIG. 1 is a top view of a mattress in accordance with a first embodiment of the invention;

(3) FIG. 2 is a sectional view of the mattress of FIG. 1, taken along line II-II; and

(4) FIG. 3 is a top view of a mattress in accordance with a second embodiment of the invention.

DETAILED DESCRIPTION OF THE DRAWINGS

(5) Referring to FIGS. 1 and 2, a mattress 2 comprising a perimeter rail 4, two rectilinear sections 6a and 6b, and a spacing means comprising a flexible spacer 8 is shown. The perimeter rail 4 is composed of a head end 10, a foot end 12, and two sides 14a and 14b. The head end 10 has an inner surface 20 and the foot end 12 has an inner surface 22. The side ends 14a and 14b have an inner surface 24a and 24b. The width of the perimeter rail 4 is represented in FIG. 1 by D.sub.1 and the height of the perimeter rail 4 is represented in FIG. 2 by D.sub.2. The dimensions of the width D.sub.1 and the height D.sub.2 can be varied depending on the intended dimensions of the mattress, but it is particularly appropriate to use the standard dimensions, for example a width D.sub.1 of 3.5 inches and a height D.sub.2 of 5 inches.

(6) Referring again to FIG. 1, the sections 6a and 6b lie substantially parallel to each other and are attached to at least the inner surface 20 of the head end 10 and to the inner surface 22 of the foot end 12, of the perimeter rail 4.

(7) Referring again to FIG. 2, the two rectilinear sections 6a and 6b comprise an array of springs 31 (not shown in detail) that are vertically disposed when in a use position. Arrays of springs in mattresses are well understood by those skilled in the art. The tension of the array of springs 31 for each of the sections 6a and 6b is selected to provide a predetermined firmness for each of the sections 6a and 6b. The height of the array of springs 31 and the height D.sub.2 of the perimeter rail 4 can be varied, but are best suited where the array of springs 31 has a height in an uncompressed position that exceeds the height D.sub.2 of the perimeter rail 4. When a user is lying upon the mattress 2, the array of springs 31 compress slightly due to the user's weight. If the height of the array of springs 31 in an uncompressed position does not exceed the height D.sub.2 of the perimeter rail 4, a user whose body extends beyond the length of the mattress 2 when lying down (and therefore compressing the array of springs 31) may come into contact with the perimeter rail 4 and cause the user to suffer discomfort. Also, if a user is sitting on the edge of the mattress 2, contact of his/her legs with the perimeter rail 4 may cause discomfort. Therefore, it is preferable to provide for the height of the array of springs 31 in an uncompressed position to be greater than the height of the perimeter rail 4. Preferably, standard heights are selected, for example a height of 6.5 inches for the array of springs 31 and a height of 5 inches for the perimeter rail 4.

(8) Referring to FIG. 3, the array of springs 31 (shown in FIG. 2) comprises a plurality of sub-arrays of springs (not shown in detail). Each sub-array of springs has a pre-selected tension to provide a plurality of different firmness zones within the sections 6a and 6b. In the example shown, section 6a has two different firmness zones 25 and 26 and section 6b has three different firmness zones 27, 28, and 29. A person skilled in the art will readily recognize that the number and size of the different firmness zones may be varied, with any reasonable combination of zones such as those exemplified in FIG. 3.

(9) Referring again to FIG. 2, the perimeter rail 4 further contains an upper face 30 and a lower face 32 and the sections 6a and 6b further contain an upper face 34 and a lower face 36. The upper face 30 of the perimeter rail 4 and the upper face 34 of the sections 6a and 6b are attached to an upper resilient layer 38. The lower face 32 of the perimeter rail 4 and the lower face 36 of the sections 6a and 6b are attached to a lower resilient layer 40. The upper resilient layer 38 and the lower resilient layer 40 are constructed of any suitable resilient and durable material, for example foam, such as latex, polyurethane, or visco. In one variant, at least one of the upper resilient layer 38 and the lower resilient layer 40 is manufactured from dense fibers. Variations in the covering materials can be made, using known construction methods. For example a second upper resilient layer can be provided, which can be constructed of any suitable resilient and durable material, for example foam, such as latex, polyurethane, or visco. Alternatively, the second upper resilient layer can be manufactured from dense fibers.

(10) The flexible spacer 8 is positioned between the sections 6a and 6b and keeps adjacent sections 6a and 6b separated. The flexible spacer 8 may be constructed of any suitable resilient and durable material, for example foam. The flexible spacer 8 is retained along its length between the upper resilient layer 38 and the lower resilient layer 40, and at its end to the perimeter rail 4. Optionally, the flexible spacer 8 may be attached along its length to the adjacent array of springs 31. The width of the flexible spacer 8 is selected according to its material of construction so as to provide semi-rigidity, to optimise the restriction on translation of movement between the adjacent sections 6a and 6b. However it has been found that for the construction of the mattress of the invention, the width of the flexible spacer 8 can be surprisingly small, generally significantly less than the width D.sub.1 of the perimeter rail 4.

(11) While the invention has been particularly shown and described with reference to the preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and detail may be made without departing from the spirit and scope of the invention.