Abstract
A foam core (12) for a cushion (8, 9) of a seat part (2) or a reclining part or a back rest (3) of a piece of upholstered furniture (1) or a motor vehicle seat (11) or for a mattress or support surface of a piece of reclining furniture, with a core base (13) of foam material, in particular of cold foam, visco foam, latex foam or molded foam, there being in the core base (13) a plurality of spring strips (14) which run preferably at least essentially parallel to one another. It is provided that at least one spring strip (14) has an in particular pultruded fiber core (20) which has preferably glass fibers, and a mantle (21) of a thermoplastic material, in particular of polypropylene, which surrounds the fiber core (20).
Claims
1-16. (canceled)
17. A foam core for a cushion of one of a seat part, a reclining part, a back rest, a mattress or other support surface, comprising: a core base of foam material containing a plurality of spring strips, wherein at least one spring strip has a fiber core and a mantle of a thermoplastic material which surrounds the fiber core, and wherein the spring strips have been foamed into the core base in a manner forming al layered structure in the form of foam-spring stripes.
18. The foam core as claimed in claim 17, wherein the spring strips extend at least one of between a front and back face of the core base; or essentially parallel to at least one of a top or bottom of the core base.
19. The foam core as claimed in claim 17, wherein a strip leg protrudes from the mantle on each of opposite sides thereof.
20. The foam core as claimed in claim 19, wherein the strip leg has a width that is greater than a diameter of the fiber core.
21. The foam core as claimed in claim 19, wherein a maximum thickness of the strip leg is smaller than the diameter of the fiber core.
22. The foam core as claimed in claim 19, wherein the spring strip is mirror-symmetrical around a central axis of at least one the strip leg or of the core running perpendicular to the central axis of the leg.
23. The foam core as claimed in claim 17, wherein the fiber core of the spring strip has a fiber core strand and a winding which at least in part helically surrounds the fiber core strand so that intermediate spaces are formed for interlocking with the thermoplastic material of the mantel.
24. The foam core as claimed in claim 17, wherein the spring strips are embedded in a foam into the core base.
25. The foam core as claimed in claim 17, wherein each strip leg has a plurality of openings.
26. The foam core as claimed in claim 17, wherein a lower core base part has a higher degree of hardness than an upper core base part.
27. The foam core as claimed in claim 17, wherein the spring strips are located in a central region of the core base.
28. The foam core as claimed in claim 17, wherein the core base has at least one further layer of a cushion material above the core base having a lower degree of hardness than the core base.
29. A cushion, mattress or support surface comprising: a foam core having a core base of foam material containing a plurality of spring strips, wherein at least one spring strip has a pultruded fiber core and a mantle of a thermoplastic material which surrounds the fiber core.
30. The cushion, mattress or support surface as claimed in claim 29, wherein the foam core is located in an outer covering.
31. A piece of upholstered furniture having a support surface with at least one foam core of foam material containing a plurality of spring strips, wherein at least one spring strip has a pultruded fiber core and a mantle of a thermoplastic material which surrounds the fiber core.
32. The piece of upholstered furniture as claimed in claim 31, wherein ends of the spring strips extending beyond a first edge and a second edge of a base of the piece of furniture.
33. A foam core for a cushion of one of a seat part, a reclining part, a back rest, a mattress or other support surface, comprising: a core base of foam material containing a plurality of spring strips, wherein at least one spring strip has a fiber core and a mantle of a thermoplastic material which surrounds the fiber core, and wherein the spring strips are located between an upper core base part and a lower core base part, and wherein the upper core base part and the lower core base part are adhered to one another at facing surfaces thereof.
34. The foam core as claimed in claim 33, wherein a strip leg protrudes from the mantle on each of opposite sides thereof and wherein the strip leg has a width that is greater than a diameter of the fiber core.
35. The foam core as claimed in claim 33, wherein a strip leg protrudes from the mantle on each of opposite sides thereof and wherein a maximum thickness of the strip leg is smaller than the diameter of the fiber core.
36. The foam core as claimed in claim 33, wherein a strip leg protrudes from the mantle on each of opposite sides thereof and wherein the spring strip is mirror-symmetrical around a central axis of at least one the strip leg or of the core running perpendicular to the central axis of the leg.
37. The foam core as claimed in claim 33, wherein the core base is formed of a foam material from the group consisting of cold foam, visco foam, latex foam or molded foam, wherein the spring strips run at least essentially parallel to one another, wherein the fibers of the fiber core of said at least one spring strip comprise glass fibers, and wherein the thermoplastic material of said mantle comprises polypropylene.
38. The foam core as claimed in claim 33, wherein the lower core base part has a higher degree of hardness than the upper core base part.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0067] FIG. 1 shows a perspective, partially cutaway view of a piece of upholstered furniture in accordance with the invention,
[0068] FIG. 2 shows a perspective view of a motor vehicle seat with the indicated spring strips,
[0069] FIG. 3 shows a perspective view of a foam core in accordance with the invention, cut on the front,
[0070] FIG. 4 shows a sectional view of a foam core in accordance with the invention in a plan view,
[0071] FIG. 5 shows a view of another embodiment of a foam core in accordance with the invention corresponding to FIG. 3,
[0072] FIG. 6 shows another embodiment of a foam core in accordance with the invention corresponding to FIG. 3,
[0073] FIG. 7 shows a schematic section of a foam core in accordance with the invention in a plan view in the state placed on a seat part,
[0074] FIG. 8 shows a schematic sectional view of a foam core in accordance with the invention in a side view in the state placed on a seat part,
[0075] FIG. 9 shows a schematic sectional view of a foam core for a motor vehicle seat,
[0076] FIG. 10 shows a plan view of a spring strip in accordance with the invention with different perforating,
[0077] FIG. 11 shows a cross sectional view of the spring strip taken along line VII-VII in FIG. 10 viewed in the arrow direction,
[0078] FIG. 12 shows a plan view of the fiber core of a spring strip and
[0079] FIG. 13 shows a sectional view of one part of a spring strip in accordance with the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0080] FIG. 1 shows a piece of upholstered furniture 1, its being a sofa here. The sofa has a seat part 2 and a back rest 3 as well as side cheeks 4, 5. The side cheeks 4, 5 are part of a base 6 which stands on the floor on corresponding feet 7. The seat part 2 here has two cushions 8, while the back rest 3 likewise has two cushions 9. The cushions 8 of the seat part 2 are placed on the base 6, while the cushions 9 of the back rest 3 rest on a rear cheek 10 of the base 6. The cushions 8, 9 of the piece of upholstered furniture 1 are separate elements here which can be removed from the base 6. But it is also fundamentally possible for the cushions 8 and/or 9 not be removable after completion of the piece of upholstered furniture 1.
[0081] FIG. 2 shows a motor vehicle seat 11 which likewise has a seat part 2 and a back rest 3. Here the back rest 3 can be swiveled relative to the seat part 2. The seat part 2 and also the back rest 3 of the vehicle seat 11 each have a cushion 8 which is however tightly joined to the seat part 2 and the back rest 3 respectively. Differently than in the embodiment of the piece of upholstered furniture 1, the cushions 8 for the vehicle seat 11 are not removable, but are an integral component of the seat part 2 and the back rest 3.
[0082] In the two embodiments it is such that the cushion 8 has a foam core 12. The foam core 12 has a core base 13 of foam material. The foam material of the core base of the piece of upholstered furniture 1 here is a cold foam, in particular of PU or PUR, while the core base 13 of the cushion 8 of the seat part 2 for the vehicle seat 11 is molded foam, in particular of PU or PUR. The use of comfort foam, visco foam and/or latex or latex foam is also possible.
[0083] The preceding and also the following statements apply not only to a cushion of a seat part, but in the same way also to a cushion of a reclining part and a mattress or support surface of a piece of reclining furniture, in particular a bed. Ultimately, a mattress or a support surface of a piece of reclining furniture is nothing but a cushion of the piece of furniture in this respect.
[0084] At this point it is significant, and this applies both to the embodiment of the piece of upholstered furniture 1 and also to the embodiment of the vehicle seat 11, that in the core base 13 there are a plurality of spring strips 14 which run preferably at least essentially parallel to one another.
[0085] It is pointed out that the spring strips 14 provided in the core base 13 each have an identical shape and execution. But, it is also possible for there to be different spring strips in the core base. Thus, for example, strips of different width and/or strips with different spring properties are easily possible. In the illustrated embodiment of the piece of upholstered furniture 1 only in the cushions 8 of the seat part 2 are there spring strips 14, but not in the cushions 9 of the back rest 3. However, the cushions 9 of the back rest 3 can likewise be provided with spring strips 14. In the embodiment of the vehicle seat 11 there are spring strips 14 in the cushions 8 both of the seat part 2 and also of the back rest 3.
[0086] The spring strips 14 which have spring-elastic properties extend lengthwise or transversely between the front and the back face 15, 16 of the core base 13. Relative to the piece of upholstered furniture 1 and/or the vehicle seat 11, the spring strips 14 run either lengthwise or transversely to the front face 17 of the seat part 2. In the illustrated exemplary embodiment, the spring strips 14 in the seat part 2 run transversely to the front face 17, while the spring strips 14 of the cushion 8 of the back rest 3 of the vehicle seat 11 run parallel to the front face 17 of the seat part 2. Instead of the illustrated arrangement of the back strips 14 they can however also be arranged vertically, therefore offset by 90 to the illustrated arrangement. Otherwise the spring strips 14 are in any case arranged at least essentially parallel to the top 18 and/or to the bottom 19 of the core base 13 in the upholstered furniture embodiment. In the vehicle seat embodiment, the spring strips 14 are arranged in one horizontal plane to the top and/or bottom of the core base 13.
[0087] FIGS. 10 to 13 show the structure of a spring strip 14. The spring strips 14 which are accommodated in the foam core 12 and/or the core base 13 and integrated therein can be made fundamentally identical, but can also have a different hardness, in particular can be made softer to the sides. Each of the spring strips 14 has one fiber core 20 of a fiber material, in particular of glass fibers, and a mantle 21, in particular of a thermoplastic material, in particular of polypropylene, which surrounds the fiber core 20. The mantle 21 forms the matrix for the fiber core 20. Each of the spring strips 14 has an elongated shape. The stability and bearing capacity of the spring strip 14 are ensured essentially by the fiber core 20. The fiber core 20 forms a strand which in any case has an at least essentially circular solid cross section in the embodiment shown in FIG. 11. Basically, it is also possible for the fiber core 20 to have different cross sectional shapes. Thus for example an elliptical cross sectional shape is possible. A vertical or horizontal arrangement within the mantle 21 then allows corresponding properties of bearing capacity and spring properties of the spring strip 14. Furthermore, angular, in particular rectangular cross sectional shapes of the fiber core 20 are also possible. Moreover, the aforementioned properties can also be influenced by a change of the diameter D of the fiber core 20.
[0088] As is apparent from FIGS. 12 and 13, around the strand-shaped fiber core 20 is a winding 22 which surrounds the fiber core 20. The winding 22 consists of the same material as the fiber core 20. Adjacent turns 23 of the winding 22 are spaced apart from one another without contact. This yields intermediate spaces 24 between adjacent turns 23. The intermediate spaces 24 in the longitudinal direction of the fiber core 20 form undercuts for the material of the mantle 21 so that ultimately a type of interlocking arises. As follows in particular from FIG. 13, this leads to a form-fit between the material of the mantle 21 and the fiber core 20. This improves the connection between the material of the mantle 21 and the fiber core 20 which also results essentially from shrink fitting of the outer material onto the inner material in production.
[0089] FIG. 11 illustrates that one strip leg 25, 26 of each strip 14 protrudes from each of opposite sides from the mantle 21 which is made essentially annular. The strip legs 25, 26 extend in the radial direction away from the mantle 21. The width B of the strip leg 25, 26 in the illustrated embodiment is greater than the diameter D of the fiber core 20 by more than the factor of 2, here roughly by the factor 2.5, specifically preferably by the factor of 4 to 5. Otherwise, the thickness d of the strip leg 25, 26 is much smaller than the diameter D of the fiber core 20. This results in a spring strip 14 with a thickened central region and relatively narrow elongated strip legs 25, 26 which extend over the entire length of the spring strip 14. Due to the relative [sic] long strip legs 25, 26 there results good a joining possibility of the strip leg 25, 26 to the surrounding foam of the core base 13.
[0090] Otherwise, FIG. 11 shows that the spring strip 14 viewed in cross section is mirror-symmetrical around one central axis x of the leg placed through the strip leg 25, 26 and around one central axis y of the core placed through the diameter D of the fiber core 20 and running perpendicular to the central axis x of the leg. This symmetry simplifies the production of a fiber core 12 in accordance with the invention since a certain alignment of the spring strips 14 in the production of the foam core 12 need not be considered.
[0091] As FIG. 10 in particular shows, in each strip leg 25, 26 there are a plurality of openings 27. There are openings 27 at regular intervals and/or in a repeating arrangement in the strip leg 25, 26. In the embodiment shown in FIG. 10, the openings 27 in the strip leg 25 have a round shape, while in the strip leg 26 there are rectangular openings 27. This type of arrangement of openings 27 is used to not only represent possibilities of the formation of openings 27. Generally, the openings 27 in both strip legs 25, 26 for a spring strip 14 have the same opening shape, but in any case the free opening area, i.e. the sum of the opening areas of all openings 27, should be relatively large. In any case the free opening area of the openings 27 relative to the total area of the respective strip leg 25, 26 should be greater than 20%.
[0092] FIG. 3 shows a fiber core 12, whereby the spring strips 14 have been foamed into the core base 13. The foam material used is molded foam. The spring strips 14 in the embodiment according to FIG. 3 are located in the region of the lower third of the core base 13, whereby the foam material above and underneath the spring strips 14 is identical. As follows from FIG. 4, the spring strips 14 extend from the front face 15 to the back face 16, the respective ends of the spring strips 14 not lying exposed, but being enclosed also by the foam material of the core base 13. But it should be pointed out that it is fundamentally also possible for the two ends of the respective spring strips 14 to lie exposed on the front face 15 and/or back face 16 of the core base 13, therefore to be visible to an onlooker.
[0093] The foam core shown in FIG. 3 is intended for a cushion of a seat part 2. In the case of a mattress or support surface, only the length of the foam core 12 and the number of spring strips 4 are greater. Otherwise there are no differences in type and structure, as was already pointed out at the beginning.
[0094] In the embodiment shown in FIG. 5, the core base 13 has been produced differently. The core base 13 here has an upper core base part 28 and a lower core base part 29. It is cut foam here, for example, of cold foam. Both core base parts have the same surface area, but a different thickness. To produce the foam core 12, adhesive is applied to the top of the lower core base part 29. Then the spring strips 14 are put in place in the desired arrangement. Then adhesive is applied again to the top of the spring strips 14. Then the upper core base part 28 is put in place and pressed against the lower core base part 30 and the interposed spring strips 24 and thus adhered.
[0095] Both in foaming and also in the above described production method by means of adhering, the openings 27 are used for tight joining of the spring strips 14 to the foam material, specifically when laying in foam, in that the foam penetrates through the openings 27, while in the other embodiment the adhesive penetrates through the openings 27.
[0096] Instead of the production method described in FIG. 5, it is also fundamentally possible to replace the upper core base part 28 or the lower core base part 29 by a foaming process, whereby the pertinent spring strips 14 then lying exposed on the respective bottom or top. Then the other core base part can be joined by an adhesive connection to the core base part produced by foaming.
[0097] In the embodiment shown in FIG. 5 the lower core base part 29 can have a higher degree of hardness than the upper core base part 28. The higher degree of hardness can be produced for example by a denser plastic material or a different plastic material with a corresponding increased degree of hardness. In any case it should preferably be such that at least the part of the foam material of the core base which is located underneath the plane of the spring strip 14 is harder, therefore has a higher degree of hardness than the region of the foam core which is located on the top 18. One embodiment in this respect is shown in FIG. 6. There, for example, the core base 13 has been produced by foaming with a foam with a higher degree of hardness. This foamed part ultimately forms the lower core base part 29. The upper core base part 28 is applied as another layer to the lower core base part and joined for example via an adhesive connection.
[0098] It should be pointed out that it is fundamentally possible to provide other layers on the top and/or bottom of the base part which has spring strips 14, and the layers provided on the top can have fundamentally a lower degree of hardness, but also the same degree of hardness as the layers provided in the lower region of the core base 13.
[0099] FIGS. 7 and 8 show an embodiment in which in the plane of the spring strips 14 on the edge side circumferentially in the manner of a frame there is a region of the core base 13 with a higher degree of hardness than the degree of hardness of the foam of the upper core base part. In doing so, the spring strips 14 are placed not only on the lower core base part 29, but also with the strip legs 25, 26 blanket the material of the lower core base part 29 and are partially embedded therein. This then yields the reinforced frame function.
[0100] While the foam core 12 in the upholstered furniture embodiment has essentially a rectangular shape, the foam core 12 for the vehicle seat 11, and both with respect to the seat part 2 and also the back rest 3, is rather a shell-like body with side cheeks. The embodiment shown in FIG. 9 is a cross sectional view of the cushion 8 for the back rest 3, the spring elements 14 running transversely to the cheeks of the back rest 3, while the spring strips 14 for the seat part 2 are aligned at least essentially in the direction of the seat cheeks.
[0101] On the side facing the user, the cushion 8 in the embodiment according to FIG. 9 has a covering 30, while on the side facing away from the user there is a metal part 31 which ultimately forms a support for the foam core 12 and also the spring strips 14.
[0102] The embodiment according to FIG. 1 illustrates that the cushion 8 likewise has an outer covering 30. Furthermore, between the foam core 12 and the covering 30 is a layer 32 with cushion wadding. Between the layer 32 and the covering 30 there can be another clamping material in the form of a nonwoven material, in particular polyester nonwoven material.
[0103] FIGS. 7 and 8 illustrate the principle of the arrangement and support of the foam core 1 on the seat part 2 or the back rest 3. The following statements relate to the seat part 2 of the piece of upholstered furniture 1, but also apply in the same way to the embodiment with the vehicle seat 11, and both to the seat part 2 and also to the back rest 3.
[0104] The seat part 2 here on the base 6 has a first edge 33 and a second edge 34. The first edge 33 is adjacent to the front face 17, while the second edge 34 is opposite the first edge 33 and adjacent to the back rest 3. In the region of the back rest 3 of the vehicle seat 1 are the supporting edges laterally on a rigid part of the back rest, for example on a frame.
[0105] FIG. 7 illustrates that the cushion 8 is placed on the edges 33, 34, therefore is supported on them. Here the spring strips 14 have a length such that they likewise overlap the edges 33, 34 with their ends, viewed from overhead. The length of the spring strips 14 is therefore greater than the clear distance of the two edges 33, 34 to one another. In any case, with corresponding loading of the cushion 8 the spring strips 14 are thus also indirectly supported on their ends on the respective edges 33, 34.
[0106] Otherwise, it is such that, underneath the cushion 8, in any case, in the upholstered furniture embodiment, there is no lower cushioning or a spring core. The bottom of the cushion 8 forms the lower termination of the cushion structure in any case in a functional respect. It goes without saying that there can be lower under-clamping which however with respect to the cushioning does not assume any bearing or spring properties. The corresponding applies to reclining furniture when the cushion 8 is a mattress or support surface.
