Cylindrical foam body, use thereof and method for producing this

Abstract

Cylindrical foam body with a central cavity, whereby the foam body is formed by a curved flexible foam strip of which two opposite ends are fastened together, whereby the foam body has a height, whereby the strip 2 has a length, a height and a width, whereby after forming the foam body the longitudinal direction of the strip 2 is the height direction of the foam body, whereby the foam body has an outside and an inside. The foam body is provided on its outside with two or more grooves that extend over the height of the foam body and which only cut into the foam body over a part of the distance between the outside and the inside.

Claims

1. A cylindrical foam body (1) with a central cavity (9), the foam body (1) formed by a curved flexible foam strip (2) of which two opposite ends (3) are fastened together, whereby the foam body is defined by a first height (H) in a height direction, and the foam strip (2) has a length (L) in a longitudinal direction, a second height (h), and a width (b), whereby after forming the foam body (1), the longitudinal direction of the foam strip (2) is the height direction of the foam body (1), and the foam body (1) has an outside (5) and an inside (8), wherein the foam body (1) is provided on the outside (5) with two or more grooves (7) that each extend over an entirety of the first height (H) of the foam body (1) and which only cut into the foam body (1) over a part of a distance between the outside (5) and the inside (8).

2. The foam body according to claim 1, wherein before forming the foam body (1), the flexible foam strip (2) is provided with cuts (13) that extend over the length (L) of the foam strip (2) that corresponds to the first height (H) of the foam body (1), whereby after formation of the foam body (1) the cuts (13) form the grooves (7) in the foam body (1).

3. The foam body according to claim 1, wherein before forming the foam body the flexible foam strip (2) is provided with milled grooves (13) that extend over the length (L) of the foam strip (2) that corresponds to the first height (H) of the foam body (1), whereby after formation of the foam body (1) the grooves (13) in the foam strip (2) form the grooves (7) in the foam body (1).

4. The foam body according to claim 1, wherein before forming the foam body (1) the flexible foam strip (2) is provided with a regular wave pattern that is made over an entire surface (11) of the foam strip (2), whereby the waves of the wave pattern extend essentially perpendicular to the longitudinal direction of the foam strip (2), and whereby after formation of the foam body (1) the wave troughs (16) form the grooves (7) in the foam body (1).

5. The foam body according to claim 1, wherein the number of the said grooves (7) in the foam body is six or more.

6. The foam body according to claim 1, wherein the said grooves (7) in the foam body (1) run parallel to the height direction of the foam spring (1).

7. The foam body according to claim 1, wherein the flexible foam strip (2) is composed of more than one sub-strip in the longitudinal direction.

8. The foam body according to claim 1, wherein the flexible foam strip (2) is composed of more than one sub-strip in a transverse direction (b) thereof.

9. The foam body according to claim 1, wherein the flexible foam strip (2) is composed of more than one sub-strip in a direction of the second height (h).

10. A mattress or pillow comprising a foam spring, wherein the foam spring comprises the foam body (1) according to claim 1.

11. A method for making a cylindrical foam body (1), comprising the following steps in order: A: providing a flexible foam strip (2) with cuts (5), grooves (13) or a wave pattern, which traverse across an entire length (L) of the foam strip (2) but do not bridge a distance between a top surface (11) of the foam strip (2) and a bottom surface (12) of the foam strip (2); and B: bending the foam strip (2) around and connecting together two opposite ends (3) of the foam strip (2) to fix a rounded position whereby an axis around which the foam strip (2) is curved runs parallel to the cuts (5), grooves (13) or wave pattern.

12. The method according to claim 11, wherein the method produces a cylindrical foam body (1) with a central cavity (9), the foam body (1) formed by the flexible foam strip (2) of which the two opposite ends (3) are fastened together, whereby the foam body is defined by a second height (H) in a height direction, and the foam strip (2) has the length (L) in a longitudinal direction, the height (h), and a width (b), whereby after forming the foam body (1), the longitudinal direction (L) of the foam strip (2) is the height direction of the foam body (1), and the foam body (1) has an outside (5) and an inside (8), wherein the foam body (1) is provided on the outside (5) with two or more grooves (7) that each extend over an entirety of the second height (H) of the foam body (1) and which only cut into the foam body (1) over a part of a distance between the outside (5) and the inside (8).

13. The method according to claim 11, wherein immediately after step B the length (L) of the curved foam strip (2) is greater than a height (H) of the foam body (1), whereby after step B the foam body (1) with the height (H) is cut from the curved foam strip (2).

14. The method according to claim 11, wherein before step B the length (L) of the flexible foam strip (2) corresponds to a height (H) of the foam body (1), whereby the cuts or grooves extend over the entire length (L) of the foam strip (2) or whereby the wave pattern extends over an entire surface (11) of the foam strip (2).

15. The foam body according to claim 2, wherein before forming the foam body the flexible foam strip (2) is provided with milled grooves (13) that extend over the length (L) of the foam strip (2) that corresponds to the first height (H) of the foam body (1), whereby after formation of the foam body (1) the grooves (13) in the foam strip (2) form the grooves (7) in the foam body (1).

16. The foam body according to claim 2, wherein before forming the foam body (1) the flexible foam strip (2) is provided with a regular wave pattern that is made over an entire surface (11) of the foam strip (2), whereby the waves of the wave pattern extend essentially perpendicular to the longitudinal direction of the foam strip (2), and whereby after formation of the foam body (1) the wave troughs (16) form the grooves (7) in the foam body (1).

17. The foam body according to claim 3, wherein before forming the foam body (1) the flexible foam strip (2) is provided with a regular wave pattern that is made over an entire surface (11) of the foam strip (2), whereby the waves of the wave pattern extend essentially perpendicular to the longitudinal direction of the foam strip (2), and whereby after formation of the foam body (1) the wave troughs (16) form the grooves (7) in the foam body (1).

18. The foam body according to claim 2, wherein the number of the said grooves (7) in the foam body is six or more.

19. The foam body according to claim 3, wherein the number of the said grooves (7) in the foam body is six or more.

20. The foam body according to claim 4, wherein the number of the said grooves (7) in the foam body is six or more.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) With the intention of better showing the characteristics of the invention, preferred embodiments of a foam body according to the invention are described hereinafter by way of an example, without any limiting nature, with reference to the accompanying drawings, wherein:

(2) FIG. 1 schematically shows a perspective view of a foam body according to the invention;

(3) FIG. 2 shows a starting product for the production of the foam body of FIG. 1;

(4) FIG. 3 schematically shows a perspective view of an alternative foam body according to the invention;

(5) FIG. 4 shows a starting product for the production of the foam body of FIG. 3;

(6) FIG. 5 shows a partial side view and a partial cross-section of a tool for producing the starting product of FIG. 4;

(7) FIG. 6 schematically shows a perspective view of another alternative foam body according to the invention;

(8) FIG. 7 shows a starting product for the production of the foam body of FIG. 6;

(9) FIG. 8 shows a flexible foam strip composed of more than one sub-strip in its longitudinal direction;

(10) FIG. 9 shows a flexible foam strip composed of more than one sub-strip in its transverse direction; and

(11) FIG. 10 shows a flexible foam strip composed of more than one sub-strip in its height direction.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

(12) The foam body of FIG. 1 is formed by an essentially cylindrical curved strip of foam, as shown in FIG. 2, of which two ends 3 are glued together and thereby form an adhesive seam 4 in the foam body 1.

(13) The foam body has a height of approximately 12 cm and a diameter of approximately 10.5 cm. The wall thickness is approximately 2.5 cm.

(14) On the outside 5 of the foam body 1, the foam body 1 is provided with thirteen teeth 6 and grooves 7, which in this example are V-shaped and which extend parallel to the height direction H over the entire height H.

(15) The inside 6 of the foam body 1 defines a central cavity 9 in the foam body 1.

(16) On account of the fact that it is under bending stress, such a foam body 1 is highly suitable for use as a foam spring to accommodate forces in the vertical direction.

(17) A mattress can be formed, for example, by tens to hundreds of such foam bodies 1 placed next to one another and provided with a covering layer.

(18) Such a foam body 1 can be produced very easily by taking a rectangular strip 2 of flexible polyurethane foam with a height h of 2.5 cm, a width b of 18 cm and a length L of 12 cm, as shown in FIG. 2, and providing this with thirteen cuts 10 at a regular distance from one another that each run over the entire length L and which have a depth A of 15 cm from the top surface 11 and which do not cut through the strip 2 down to the bottom surface 12.

(19) Such cuts 10 can be made using rotating blades for example.

(20) Hereby to prevent confusion it is noted that in this example the dimension of the strip 2 that is indicated as the width b is greater than the dimension that is indicated as the length L.

(21) The strip 2 is then bent around in the longitudinal direction L as indicated by the arrow P, after which the two ends 3 of the strip 2 are glued together.

(22) Hereby the cuts 10 in the strip 2 are pulled open into grooves 7 and the foam body 1 thus formed. As a result they enable the foam body 1 to be formed without the foam being significantly compressed on the inside 8 and without the adhesive seam 4 resulting in a significant deformation of the foam body 1.

(23) Alternatively, such a foam body 1 can be produced continuously by unrolling a foam strip 2 rolled-up in the transverse direction b, then by guiding it through a cutting device in which the strip 2 is provided with cuts in the longitudinal direction L, then by guiding it through a bending device and a gluing device in which the strip 2 is bent around in the longitudinal direction L and the sides are glued together to form a tube structure, from which pieces can finally be cut off that correspond to the desired height H of the foam body 1.

(24) The alternative foam body 1 illustrated in FIG. 3 and the foam strip illustrated in FIG. 4, differ from the embodiment of FIGS. 1 and 2 by the strip being provided with grooves 13 instead of cuts 10. These grooves 13 have a rounded end 14. Hereby the number of grooves 14 is ten.

(25) When being bent around into a foam body the grooves 13 in the foam strip 2 become substantially wider until they form grooves 7 in the foam body 1. The rounded end 14 of the grooves 7 reduces the risk of tear formation, which is the largest at this location in the formed foam body 1.

(26) Such a foam strip 2 can easily be produced by guiding an unprocessed foam strip under a foam cutter 15 that rotates in the direction of arrow Q as shown in FIG. 5.

(27) The alternative foam body 1 illustrated in FIG. 6 and the foam strip 2 illustrated in FIG. 7, differ from the embodiment of FIGS. 1 and 2 by the strip 2 being provided with a wave pattern that is made with a convoluter machine.

(28) In such a machine foam is guided between toothed rollers, which compress the foam or not depending on the location, and cut in this position in the longitudinal direction, so that differences in height occur between parts of the foam that were compressed when they were cut and parts that were not compressed when they were cut.

(29) The number of wave troughs 16 in the wave pattern is nine in this example.

(30) When being bent around into a foam body 1 the wave troughs 16 in the foam strip become substantially wider until they form the grooves 16 in the foam body 1.

(31) In order to obtain a foam spring with an equal diameter D to the above two embodiments, in this embodiment the length L of the strip 2 has to be taken to be ten to twenty % greater.

(32) It will be clear that the elastic properties of the foam body 1 can be easily adjusted, of course by adjusting the nature of the foam, but also by adjusting the depth A, the number and form of the cuts 10, grooves 13 and wave troughs 16.

(33) As shown in FIGS. 8-10, the flexible foam strip may be composed of more than one sub-strip in its longitudinal direction (FIG. 8), its transverse direction (FIG. 9) or its height direction (FIG. 10).

(34) The present invention is by no means limited to the embodiment described as an example and shown in the drawings, but a foam body according to the invention can be realised in all kinds of forms and dimensions, without departing from the scope of the invention.