WO2004034852A1

WO2004034852A1 - Foam and coil mattress combination

Info

Publication number: WO2004034852A1
Application number: PCT/IB2002/003936
Authority: WO
Inventors: Gualtiero Giori; Janine Giori
Original assignee: Gualtiero Giori; Janine Giori
Priority date: 2002-09-23
Filing date: 2002-09-23
Publication date: 2004-04-29
Also published as: CN1668229A; DE60226519D1; EP1569540B1; JP2005537902A; AU2002337399A1; EP1569540A1; ATE394048T1

Abstract

The invention modulates the air-volume in both mattress-type foam and traditional coil spring cores interactively, obtaining a wide variety of levels of density and indentation force deflection (IFD or spring-back force) .The mattress is enclosed in an airtight cover chamber (A) comprising a valve (12) for evacuating air. In addition, foam and coil spring cores may be enclosed in additional airtight chambers (B) (C) having their own valve (34, 46, 45) to evacuate air. Applying vacuum selectively within the various chamber of the mattress allows to modulate the comfort characteristics of the mattress. The invention takes advantage of the unique interactive behavior of self-inflating foam and coil spring constructions to create multiple levels of comfort for one or more users of the same device.

Description

FOAM AND COIL MATTRESS COMBINATION

Field of the Invention This invention relates to an interactively modulable support apparatus, such as a mattress, having a layer of pressure adjustable self-inflating, open- cell, flexible polyurethane foam core and a layer of mattress spring coils. Both layers are independently adjustable as to softness/hardness, but also interactively modulable in the way that adjustment of the foam core layer modifies the characteristics of the coil spring layer.

Background of the Invention This invention is a multiple layer combination mattress. One or more layers are self-inflating elastomeric open-cell polyurethane foam and another layer is a section having mechanical coil springs therein. Both layers are individually, as well as interactively adjustable as to their hardness and softness (indentation force deflection - IFD) and support (density). Various designs have been made in the past to control the hardness, softness, and support firmness of foam layers within a mattress by using different zones of foam layers for different parts of the body, or by controlling the firmness or responsiveness of coil springs in mattresses. However, the control of both layers so that they can be adjusted by the user, foam and coil independently and interactively in one mattress, has not been achieved and is not found in the prior art in the manner of this invention. Prior art mattressess exists having a coil spring core and one or more foam zones. The foam layers typically have different density and IFD ratings to accommodate the weight of various parts of the body, such as the head, shoulders, middle body, and feet. The coil spring core supports the layers of foam and is surrounded by a quilted fabric or ticking which is serves as outer decoration as well as holds the parts of the mattress together as one whole mattress.

The disadvantages of said mattress is that it is often very expensive, and yet offers only one fixed comfort level that can not be selectively modulated by the user. Yet other mattresses have interchangeable foam compartments to achieve different comfort levels, however said multi-foam compartment mattresses become cumbersome due to a multitude of foam compartments that must be stored when not in use.

Other prior art mattress have an upper foam layer and one or more air bladders placed underneath which can be pressurized by an air pump. A person reclining on the mattress impresses his or her mass on the mattress, accumulating towards the area of least lateral support, that is, in the center. This results in a hammock effect, which is uncomfortable for a person resting on the mattress. Moreover, when air is let out of the bladder, the entire apparatus collapses and does no longer support the reclining body. In this arrangement the air chamber is modulated below the foam layer without any interactive effect on the foam. In case of loss of pressure, the air chamber wobbles and sways, rendering the structure unstable and even more uncomfortable. US Patent No. 2,779,034 to Arpin discloses a firmness adjustment for mattresses involving a standard coil spring mattress wherein standard coil springs are enclosed by a loosely fitting airtight cover. Arpin does not mention any open-cell, self-inflating foam varieties, nor does he teach any combination of coil and foam cores in a mattress.

US Patent No. 3,872,525 and No. 4,025,974 to Lea discloses a self- inflating air mattress/mat including an airtight flexible envelope which encloses a core of resilient, open cell, lightweight foam material, substantially the entire upper and lower portions of which are bonded to the envelope. The air within can be removed by compressing the structure whereby the foam layer collapses, allowing the mat to be rolled up into a compact package.

US Patent No. 4,944,060 illustrates a mattress having a plurality of discrete, air permeable cells which are to some extent hydrophobic. The mattress uses pressurized air to inflate the mattress, and does not use any foam core.

US Patent No. 6,098, 378 discloses a method of packaging a single mattress to a small size to be conveniently carried. In this method and apparatus, the foam mattress is compressed to fit into a hard container for shipment. At the point of sale, the mattress is extracted and expands to its original shape. Description of the Invention

In contrast to prior art mattresses, the present invention modulates

80 the density and the spring-back-force (IFD) of self-inflating, open-cell, flexible polyurethane foam in combination with traditional coil spring chambers, thus doing away with most problems of prior art devices. Any weight distribution on top of such a foam & coil spring mattress, such as from the head, abdomen or the legs, affects the deflection of the foam layer surface only locally, and

85 upward recovery (spring-back) is a slow process of re-directed airflow through the cell structure of the foam layer. The underlying coil spring layer is not subjected to concentrated pressure from the weights above it. Consequently, no hammock effect will be evidenced.

Depending on the air pressure in the foam layer, there can even be a

90 state where no recovery takes place; where no upward pressure is exerted, and still a high level of comfort is sustained. This is based on the underlying principle inherent in the invention that, when air is removed progressively from a hermetically sealed foam core, the foam's density increases. At the same instance, its Indentation Force Deflection (IFD or spring-back force) is

95 progressively decreased, making the foam core softer. This process of modulation spans from full inflation to practically zero. In the extreme case, when too much air is removed, the foam hardens, defeating the purpose of a mattress, e.g. to provide comfort.

The invention results from the realization that a combination of a self-inflating,

100 adjustable density, variable IFD, open-cell flexible polyurethane foam core with a mattress layer having coils therein greatly enhances the versatility of mattress combinations, offering great variety in adjustable levels of comfort. The present invention uses, in the context of mattress manufacturing, the fact that the Indentation Force Deflection (IFD) and density properties of a certain

105 quality range of flexible open-cell polyurethane foam can be modulated by removing some of the air from within the foam cells and altering the cellular structure of the foam core.

High density foam (such as visco-elastic foam) provides great comfort but is significantly more expensive. The focal teaching of this invention is how to

110 modulate a comparatively inexpensive, lower density foam to feel similar to a high density foam, and attain support and comfort characteristics of a higher density, more expensive foam, through layer interactivity between foam and traditional coil spring arrangements, without locking the user into one fixed comfort level, but give him a wide choice between very hard and very soft

115 comfort.

IFD and density modulation are achieved by manipulating flexible polyurethane foam or material of similar characteristics. This art teaches that this material is fashioned in a particular form and that it has to be of a composition as to permit the extraction of air in the alveolate structure in a

120 uniform manner, thus increasing material density equally uniformly. A further specialty of this material is that, by virtue of its structure, particular manufacturing and finishing processes, it affords in its low IFD number modulated state commensurably higher firmness stability, heretofore only associated with foam or similar material of a very much higher density

125 number. Finally, it is much lighter in weight than the latter and can be reduced in size and volume for easy transport and storage. By compressing the coils either directly by evacuating air with a vacuum from the coil chamber, or by compressing the coil chamber with the

130 rising force of the self-inflating foam chamber, the coil portion of the mattress becomes firmer. On the other hand, if some air was evacuated from the foam chamber, the coil portion would relax and feel softer. This invention involves different reversible mattress combinations that one or more users may adjust differentially and individually to his or her liking, depending which side of the

135 bed they choose to recline upon (left or right side of the bed, or the reverse surface). It also demonstrates that many incremental levels of firmness or softness may be achieved by one piece of foam as it changes from low density and high IFD to a high density low IFD more desirable foam, as well as when it interacts with other adjacent coil cores, changing their particular

140 IFD and firmness characteristics.

The present invention can use a fan-style vacuum pump to draw air out of the foam core to double its density and to reduce its IFD value considerably. After only a few seconds of the pump's operation the foam feels like a high density, resilient foam with an IFD of under 20, supported by an equally

145 modulated coil spring layer with adjusted softness. Since the vacuum pump comes equipped with variable speed and remote control memory settings this transformation occurs at the speed and in increments desired by the user.

The experiments conducted entailed a user reclining on the foam/coil

150 spring original firm configuration and subsequently adjusting the density and

IFD settings within the foam core. It was observed that the user's heaviest parts of the body sank into the foam and were contoured progressively as the density increased and the IFD decreased. Thanks to this functionality, as well as the underlying coil spring layer, no collapsing or hammock effect took

155 place within the mattress, which was lighter and thinner than any other mattresses using a different technology - reduction in weight, bulk and cost being industry priority requirements for new mattress technology.

This invention takes advantage of the adjustability of the self-inflating foam core as to comfort and also uses said adjustability to change the

160 properties of the coil mattress above or below the foam mattress core. The structure of this combination allows the mattress cores to be used in two horizontally juxtaposed orientations. Either the foam part of the mattress faces upwards or the coil part of the mattress faces upwards. This is decided by the user of the mattress. In particular, air can be exhausted from the foam

165 part of the mattress combination uniformly with the aid of a vacuum pump, which results in increasing the density of the foam core and decreasing the IFD within the core for a softer feeling foam core with more support. Since the coil core and the foam core are trapped within an airtight outer chamber the properties of said coil core will change as the foam core expands or contracts.

170 Moreover, the coil core combination of the mattress combination may additionally be compressed by evacuating the air of the chamber containing the coils which would result in increasing the hardness of that part of the mattress but would also affect the adjacent foam core. This interactivity in adjustability contributes greatly to the versatility of such a mattress

175 combination. The basic configuration of this invention, which comes in a broad variety of combinations between foam and spring coil cores and compartments, takes the form of a mattress with layer combinations comprising an airtight cover chamber enclosing at least one core of self-

180 inflating polyurethane foam and at least one core of coil springs, said airtight cover chamber having at least one valve serving as a means to evacuate air. Said core of coil springs may include a protective layer on both its upper and lower surfaces. In a typical arrangement of the present invention, the mattress combination comprises two cores of self-inflating polyurethane foam placed

185 as the upper and lower layers of the mattress, and one core of coil springs placed in between.

In another embodiment of the invention, at least one core of self- inflating polyurethane foam of the mattress combination just described is

190 enclosed in one additional airtight chamber, said additional airtight chamber being enclosed in said airtight cover chamber and comprising at least one valve penetrating through the wall of said airtight cover chamber to evacuate air from said additional airtight chamber. In a preferred embodiment, the number of cores of self-inflating polyurethane foam enclosed in additional

195 airtight chambers is two.

In still another embodiment of the invention, the coil spring core is enclosed in a further additional airtight chamber having a same valve 200 arrangement as the other additional airtight chambers, all additional airtight chambers being enclosed in the airtight cover chamber.

In still a further embodiment of the invention, the core of self-inflating polyurethane foam is vertically subdivided into at least two longitudinal or 205 transversal sections, and the additional airtight chamber for said core is replaced by individual additional airtight chambers for each of said sections, each chamber having a same valve arrangement as full size additional airtight chambers.

In order to ensure proper airflow, the valve or valves fitted to each additional 210 airtight chamber and to the airtight cover chamber may comprise one or more air permeable distancing elements, keeping any adjacent materials from obstructing airflow through the valve or valves.

Brief Description of the Drawings

215

Fig. 1 shows one airtight chamber, two cores and a single valve with an air permeable distancing element; Fig. 2 shows one airtight chamber, three cores with a single valve with an air permeable distancing element; 220 Fig. 3 shows two airtight chambers, two cores, two valves, and two air permeable distancing elements; Fig. 4 shows three airtight chambers, three cores, three valves and three air permeable distancing elements; Fig. 5 shows three airtight chambers, two cores, three valves and three air 225 permeable distancing elements;

Fig. 6 shows subdivided chambers with a valve each; Fig. 7 shows a 4-chamber mattress in a cut-away view; Fig. 8 shows a coil foam mattress in the present invention with weights placed on the surface; 230 Fig.9 shows a coil foam mattress in the present invention when weights are removed from the surface with the valve closed; Fig.10 and 11 shows the same combination mattress in different states of self-inflation with one or more valves and one or more air permeable distancing elements;

235

Detailed Description of the Drawings

Fig. 1 shows one airtight chamber with two cores inside. Chamber (A) is the main airtight cover chamber constituting the overall mattress. The lower

240 section (B) is a self-inflating foam core (SF1), above which is placed a coil spring core (C) with a number of coil springs (11), normally placed in individual fabric sleeves (not shown). Above and below the coil spring core, protective layers (14) are provided to prevent the ends of the coil springs from protruding into a person lying on top of the chamber (A) and into the foam

245 core (B) below.

A valve, or a plurality of valves (12), installed in the wall (10) of the main chamber (A), serves to exhaust air from the mattress. An air permeable distancing element (13) prevents adjacent materials from obstructing the valves. When air is exhausted through the valve, the foam core (SF1) will be

250 compressed uniformly and the coil springs in the coil spring section will also be compressed. As a result, both density and IFD values of the two sections will change. The surface of the coil spring section will harden while, inversely, the surface of the foam core section will soften. This mattress may be used either with the foam or the coil spring section facing upwards.

255 Fig. 2 shows a combination mattress with one airtight cover chamber

(A), in which are placed two self-inflating foam cores (SF1 and SF2) in the bottom (24) and the top (25) positions, while a coil spring core (21), having protective layers (26), sandwiched in between. In the outer wall of chamber (A) a valve (22) and air permeable distancing element (23) has been provided

260 through which air can be exhausted. When this occurs, the two foam cores (24 and 25) and the coil spring core springs (21) are compressed. Under compression, the surfaces of the foam cores will soften as a result of decreasing IFD, while the coil spring core, in contrast, will increase in hardness because the coil springs are tensioned and want to return to their

265 initial relaxed state.

Fig. 3 shows a mattress combination with two chambers: an airtight cover chamber (A) with wall (30), and an additional airtight chamber (B) inside. (B) is completely self-contained and envelopes a self-inflating foam core (SF1). The upper part of chamber (A) contains a coil spring core (37)

270 with a number of coil springs (38). Protective layers (33) are placed each above and below the coil springs. Two valves (31 and 34) are provided, whereby upper valve (31) serves to exhaust air from the overall chamber (A), resulting in the compression of the upper coil spring core which will harden. Lower valve (34) serves to exhaust air from chamber (B) exclusively and

275 independently from chamber (A), if so selected. Valve (34) leads to the interior of chamber (B) by penetrating both wall (30) of the overall chamber and wall (36) of chamber (B). Both valves have air permeable distancing elements (32 and 35) attached to their interior end to prevent valve-clogging by foam or cover material.

280 This mattress combination can be used on both sides. If so desired, the coil spring core can be used to lay on because of a desire of reclining on a harder surface, or the foam core side can be used because of a softer surface. When air is evacuated from the foam core (SF1) in chamber (B), both chambers will be rendered softer because of the falling IFD value in

285 chamber (B), but also because the coil spring core (37) will relax further due to the shrinking volume in chamber (B).

Fig. 4 shows a mattress combination with three chambers. The first (A) is an airtight cover chamber (40). Inside (A) are two additional airtight chambers (B and C), each having a self-inflating polyurethane core (SF1 and

290 SF2). Sandwiched between these is a traditional coil spring core (41) protected by foam layers (42) at both ends of the springs. (A) has a valve (43) and air permeable distancing element (44) for the purpose of evacuating air from that chamber, which will result in compressing the coil spring core, increasing its firmness. The upper and lower foam surfaces, being enveloped

295 in separate chambers, remain unaffected. Chambers (B and C) also have independent valves (45 and 46), which pass through both chamber walls into the interior of their respective foam core chamber, and each valve has an air permeable distancing element (47 and 48) attached. Through these air can be evacuated either from both chambers (B and C) simultaneously or

300 independently, producing a large variety of different hardness or softness combinations. The sandwiched coil spring layer will be interactively modulated, since compression of either or both chambers (B) and (C) will result in a further extension of the springs.

Fig. 5 shows a three chamber (A, B and C) combination mattress. (A)

305 is the overall chamber enveloping the other two (B and C) and has sealed wall (50). The lower chamber (B) is filled with a self-inflating polyurethane foam core (SF1), enveloped in its own hermetically sealed cover (59). Inside the upper chamber (C) is a traditional coil spring core (51) and it also is hermetically sealed by its own cover (58). The coil spring core (51) has a

310 protective foam layer (53) placed each above and below the springs. The overall chamber (A) has a valve (56) placed therein and through its own wall (50), fitted with an air permeable distancing element (57) on the interior, which prevents the cover (58) of chamber (C) from being drawn into the valve when the air is being evacuated from this chamber. Chamber (C) also has its own

315 valve with air permeable distancing element (52) which passes through both walls (50) of chamber (A) and (58) of (C). Chamber (B) also has its own valve (54) passing through wall (50) of chamber (A) and wall (59) of chamber (B). Valve (54) is equally fitted with an air permeable distancing element to prevent the foam and covering from being drawn into the valve when air is

320 evacuated from the foam core (SF1), and it serves, in the opposite case, to distance the foam and cover from the valve when the foam core is allowed to self-inflate. The versatility of this mattress combination resides in the fact that all three valves can be operated selectively to increase or decrease the respective softness and hardness of the various cores or to decompress the

325 whole mattress for storage or transport.

When the air is evacuated from chamber (C), the coil springs (51) will be compressed, offering a higher degree of firmness. On the other hand, when the air is being evacuated from chamber (B), the self-inflating foam core (SF1) will soften but also allow chamber (C) to expand, offering a different

330 level of softness/firmness combinations interactively. When air is being evacuated from (A), both chambers (B) and (C) will be compressed by the outer cover (50) and expel air, provided the respective chamber valves are open, resulting in the coil springs being harder to compress while the foam core will soften. The mattress can be used on either side if so desired.

335 Fig. 6 shows a mattress combination with 5 chambers which are hermetically sealed from each other. Overall chamber (A) with side wall (60) encloses four other chambers (B, C1 , C2 and C3). Chamber (B) envelopes a traditional coil spring core (61) within its own sealed wall. .Below it are placed three smaller self-inflating foam (SF) sections (C1 , C2 and C3), each

340 enclosed in their own outer wall envelopes. Arrow (65) indicates how the various cores and sections are associated with each other. The overall cover of chamber (A) has its own valve (62), combined with an air permeable distancing element (62a). Chamber (B) has its own valve (63) which passes through wall (60) of the outer chamber and through its own wall. The three

345 smaller sections (C1 , C2 and C3) below are filled with self-inflating foam and have their own valves (64a, 64b and 64c) and air permeable distancing elements (one is shown at 64d). Each valve of (C1 , C2 and C3) pass though wall (60) of chamber (A) and through their own wall so that air can be evacuated from each chamber in a selective manner. The selectively

350 modulable foam core chambers control various areas of hardness and softness of the coil spring layer, corresponding to upper, middle and lower body, thus greatly enhancing the versatility of the mattress.

Fig. 7 shows a mattress combination in a cut-away view, consisting of four chambers. An outer chamber with wall (70) fully encloses and

355 hermetically seals three inner chambers (A, B, and C). (B) is the lower chamber with its own wall (72), enclosing a self-inflating foam core (SF1). So is upper chamber (C) with wall (71), enveloping self-inflating foam core (SF2). The fourth chamber (A) with its own wall (79) envelops a traditional coil spring core, and it is sandwiched between chambers (B) and (C). The coil spring

360 core has protective layers (74) placed one above and one below the spring ends.

All four chambers are fitted with valves to selectively evacuate air. Valve (75) in cover (70) is fitted with an air permeable distancing element (75a) to avoid being blocked by wall (79) of chamber (A) when air is

365 evacuated. (75) is by purpose placed in a position that, when air is evacuated from its chamber, the other three chambers are compressed, provided their respective valves are open. The lower chamber (B) with wall (72), has valve (78) with anti-blockage distancing element (78a) passing into its interior through the outer wall (70) of the overall cover and its own (72). The upper

370 chamber (C) with sealed cover (71) completely envelopes the self-inflating foam core (SF2). It has valve (76) with anti-clogging, air permeable, distancing element (76a), leading from its interior through its own wall (71) and through outer wall (70), so that only air from this chamber can be evacuated. 375 Chamber (A), which contains a traditional coil spring core (73), is sandwiched between (B) and (C). It has its own wall (79), completely enclosing the coil spring layer, so that air can only be withdrawn from it through valve (77). In order to so, this valve passes through its own wall (79) and outer wall (70). All four valves can selectively be activated to modulate 380 the air volume in any one of the four chambers, providing new levels of versatility and comfort. This mattress may also be compressed for transport or storage.

Fig. 8 shows one configuration of the present invention with weights

(W) simulating body parts sinking into the outer cover (81) and into the foam 385 core (82) surface (FS1). The coil spring core (83) is supporting the foam, but if some air is withdrawn through valve (84) and through distancing element

(85), the foam surface will become softer and contour the weights more so.

In contrast, the coil section will also compress and become firmer giving the mattress extra support. 390 Fig. 9 shows the same configuration as in Fig. 8 but with one weight removed (W1), the valve (94) is closed, and the foam core (92) and surface

(FS1) exhibit the imprint of the users body, as the foam core (92) recovers slowly upwards.

On the other hand the coil core (93) when air is removed from outer chamber 395 (91) through valve (94) and distancing element (95) will be compressed and offer more upward support. It is also possible to evacuate additional air from this mattress structure, and observe the imprint of the user's body remain on surface (SF1), hence exhibiting no upward recovery.

400 Fig. 10, shows a foam coil combination mattress in its compressed and deflated state with one or more valves (101) (102) fitted onto the chamber wall (100) and one or more air permeable distancing elements (103 shown only) to prevent clogging. Valve (102) is larger than valve (101) and may be used for rapid inflation whereas valve (101) may be used to modulate the

405 mattress combination as well as to inflate it.

Fig, 11 , shows the same foam coil combination mattress in its inflated state with one or more inflation valves (1101 & 1102) and one or more air permeable distancing elements (1103 shown only) to prevent clogging.

While the description of the patent dwells at length on different

410 applications in mattresses, other applications are not excluded, such as seats of all sorts, cushioning in all forms as well as any other application requiring a support apparatus for the enhancement of comfort and versatility.

415

420

Claims

1. A mattress with layer combinations comprising an airtight cover 425 chamber enclosing at least one core of self-inflating polyurethane foam and at least one core of coil springs, said airtight cover chamber having at least one valve serving as a means to evacuate air.

2. The mattress combination of claim 1 , wherein said core of coil 430 springs includes a protective layer on both its upper and lower surfaces.

3. The mattress combination of claim 1 or 2, comprising two cores of self-inflating polyurethane foam placed as the upper and lower layers of the mattress, and one core of coil springs placed in between.

435

4. The mattress combination of any one of claims 1 to 3, wherein at least one core of self-inflating polyurethane foam is enclosed in one additional airtight chamber, said additional airtight chamber being enclosed in said airtight cover chamber and comprising a valve penetrating through the

440 wall of said airtight cover chamber to evacuate air from said additional airtight chamber.

5. The mattress combination of claim 4, wherein the number of cores of self-inflating polyurethane foam enclosed in additional airtight

445 chambers is two.

6. The mattress combination of any one of claims 3 to 5, wherein said coil spring core is enclosed in a further additional airtight chamber having a same valve arrangement as the other additional airtight chamber or

450 chambers, and wherein all additional airtight chambers are enclosed in the airtight cover chamber.

7. The mattress combination of any one of claims 3 to 6, wherein at least one core of self-inflating polyurethane foam is vertically subdivided

455 into at least two longitudinal or transversal sections, and wherein the additional airtight chamber for said core is replaced by individual additional airtight chambers for each of said sections, each chamber having a same valve arrangement as full size additional airtight chambers.

460 8. The mattress combination of anyone of claims 1 to 7, wherein the valve or valves fitted to each additional airtight chamber or the airtight cover chamber comprise one or more air permeable distancing elements keeping any adjacent materials from obstructing airflow through said valve or valves.

465