Cushion or mattress suspension element

The invention relates to the field of furniture, and in particular to a cushion or mattress suspension element 101, 201, . . . , 901 comprising a compressible core 102, 202, . . . , 902 of flexible material and presenting at least one compression axis Z, and also comprising two bearing parts 103, 203, . . . , 903 of material that is substantially more rigid than the material of the compressible core 102, 202, . . . , 902, with at least a first bearing part being connected to one end of the compressible core 102, 202, . . . , 902 and at least one second bearing part being connected to an end of the compressible core 102, 202, . . . , 902 that is opposite along the compression axis Z, and with each bearing part presenting an outer bearing area 103a, 203a, . . . , 903a that is substantially perpendicular to said compression axis Z and, in at least one direction perpendicular to the compression axis Z, that is substantially larger than the compressible core 102, 202, . . . , 902 in its relaxed position.

TECHNICAL FIELD

The present invention relates to the field of furniture, and in particular to mattresses and cushions.

The invention relates more precisely to a cushion or mattress suspension element comprising at least a compressible core made of flexible material, that is preferably deformable in a manner that is at least partially elastic, and that presents at least one compression axis. In a particular application, a plurality of such elements are incorporated between the bottom and top faces of a mattress so as to provide a user of the mattress with support that is distributed and comfortable. Nevertheless, other applications may also be envisaged for such a cushion or mattress suspension element, such as for example in a seat cushion of a settee, armchair, or chesterfield.

BACKGROUND OF THE DISCLOSURE

In order to improve user comfort, novel materials, and in particular foams such as latex foams or high or low resilience foams, are being used in the field of stuffing mattresses and cushions. Nevertheless, such materials present certain drawbacks. In particular, in order to provide support that is sufficiently firm, it is preferable to use foams of relatively high density. That has negative repercussions both on the cost and on the weight of the cushion or mattress. Furthermore, such materials, and in particular closed-cell foams, do not provide significant ventilation.

In order to increase the sensation of firmness provided by a cushion or mattress, the person skilled in the art knows that a plurality of stiffener elements or inserts may be incorporated therein. Nevertheless, those elements are normally elastic elements that do not present the damping characteristics of foams.

SUMMARY OF THE DISCLOSURE

The present invention seeks to remedy those drawbacks. In particular, the invention seeks to propose a cushion or mattress suspension element that makes it possible to take advantage of the favorable characteristics of a flexible material in a cushion (for example) and in particular a seat cushion, or in a mattress, without making it substantially heavier, and in a manner that is less expensive.

This object is achieved by the fact that the cushion or mattress suspension element further includes at least two bearing parts of material that is substantially stiffer than the material of the compressible core. In the present context, the term “stiffer” is used to mean a material having a modulus of elasticity in compression that is greater. At least a first one of these bearing parts is connected to one end of the compressible core and at least one second part is connected to an end of the compressible core that is opposite along the compression axis, and with each part presenting an outer bearing area that is substantially perpendicular to the compression axis and, in at least one direction perpendicular to the compression axis, that is substantially larger than the compressible core in its relaxed position.

By means of these provisions, it is possible to use a compressible core of small section, while still distributing its load at both ends over the outer bearing areas. This serves to reduce the quantity of material required by the cushion or mattress suspension element, and thus to reduce its cost and its weight. In addition, the empty space around the core enables the mattress to be better ventilated, thereby improving durability.

Preferably, the flexible material of the core is a foam. Particularly, but not exclusively, it may be a high resilience foam, i.e. a foam having resilience of at least 50% in application of the ball bounce test of the standard ISO 8307. The element may thus offer a combination of firmness and damping that contributes to greater user comfort and to good durability of the core. A foam thus presents advantages of flexibility and lightness, and also better thermal insulation. Nevertheless, as an alternative to such a foam, or in combination therewith, other types of material may also be used in the compressible core, such as for example a gel or an elastic material forming a hollow body. Suitable foams include both latex foams and synthetic foams of the so-called viscoelastic type, of the shape memory type, or of the low resilience type.

Preferably, at least one of the bearing parts presents at least one through orifice for ventilation, thereby further improving the flow of air through the cushion or mattress.

In at least one embodiment, the core may present a cross-section relative to the compression axis that is cruciform, in order to avoid the core buckling. The mechanical response of the core to forces, including forces that are off-center, is thereby improved. Nevertheless, other sections may also be considered as alternatives by the person skilled in the art and depending on circumstances. In particular, a round section may be adopted if it is desired in contrast to facilitate bending of the compressible core perpendicularly to the compression axis.

Preferably, at least one of the bearing parts is fastened to the compressible core by clamping against the compressible core perpendicularly to the compression axis, thereby making it easier to assemble the cushion or mattress suspension element. Nevertheless, it is also possible to envisage other alternatives, such as adhesive bonding, for example.

Another object of the invention is to combine the mechanical response of the material of the compressible core with the mechanical response of some other material. For this purpose, in at least one embodiment, the cushion or mattress suspension element may also include at least one spring secured to at least one of the bearing parts. It then becomes possible to combine the stiffness and the resilience of the spring with the damping of the core.

Said spring is preferably formed integrally with the at least one of the bearing parts to which it is secured. This facilitates fabrication of the cushion or mattress suspension element.

In at least one embodiment, said spring is interposed between the bearing part to which it is secured and the compressible core. Thus, the spring and the compressible core are connected in series in such a manner that they are normally subjected to substantially the same compression forces along the main axis of the compressible core.

Nevertheless, as an alternative, in at least one other embodiment, said spring is secured to at least one of the bearing parts at each end of the compressible core. Thus, the spring and the compressible core are both connected in parallel and are interposed between the bearing parts at one end and at the other, in such a manner that the spring and the compressible core are normally subjected to substantially the same amount of deformation in compression along the main axis of the compressible core. Under such circumstances, said spring may advantageously be arranged to clamp against an intermediate segment of the compressible core perpendicularly to the compression axis, at least when the cushion or mattress suspension element is under compression, thereby increasing the strength of the cushion or mattress suspension element against compression over at least a portion of its compression stroke.

Preferably, said spring includes at least one flexible spring blade serving in particular to make it easier to incorporate with at least one of the bearing parts. By way of example, such a flexible spring blade may be injection molded together with at least one of the bearing parts.

In at least one embodiment, the cushion or mattress suspension element includes only one of said bearing parts at each end of the compressible core. Nevertheless, in an alternative, the cushion or mattress suspension element may have a plurality of said bearing parts at each end of the compressible core. Under such circumstances, the bearing parts at each end of the compressible core may be connected together laterally by flexible connections, and in particular by flexible connections that are formed integrally with the bearing parts. Furthermore, a plurality of cushion or mattress suspension elements may form a module in which at least one of said bearing parts of one of said elements is connected laterally by flexible connections to at least one bearing part of another one of said elements.

The present invention also provides a cushion or mattress presenting a top face and a bottom face substantially opposite said top face, and including between said bottom and top faces at least a plurality of such cushion or mattress suspension elements.

MORE DETAILED DESCRIPTION

A cushion or mattress suspension element101in a first embodiment is shown inFIG. 1A. This cushion or mattress suspension element101comprises a compressible core102of flexible material, having two opposite ends102aand102band a compression axis Z, together with a bearing part103fastened to each of the two ends102a,102b. In this first embodiment, the compressible core102presents a cross-section relative to the axis Z that is cruciform so as to stabilize it in the transverse plane and prevent it from buckling under compression. The compressible core102may be formed by extruding a flexible synthetic foam along the compression axis Z, which foam is preferably of the so-called “high resilience” type, i.e. it is conventionally understood as presenting resilience of at least 50% in a ball bounce test in application of the standard ISO 8307. In particular, the foam may be a polyurethane foam, that presents density lying more particularly in the range 30 kilograms per cubic meter (kg/m3) to 150 kg/m3. The bearing parts103are made of a material that is substantially more rigid, i.e. that presents a modulus of elasticity that is substantially higher than that of the material of the compressible core102, and each of the two bearing parts103presents an outer bearing area103athat is substantially larger than the area of the cross-section of the compressible core102. Thus, a load transmitted by the compressible core102in compression may be distributed by the bearing part103at each end of the element101over a greater bearing area. The bearing area of the element101is thus not determined by the cross-section of the compressible core102relative to the compression axis Z.

As can be seen more clearly inFIG. 1B, each bearing part103presents an inside surface103badapted to be adhesively bonded to one or the other of the ends102a,102bof the compressible core. In addition, each bearing part103also presents through orifices104around this inner surface103band serving to provide better ventilation for the cushion or mattress. By way of example, the bearing parts103may be made by injection molding. The material used may in particular, be an elastic material that is natural, such as rubber, or synthetic, in particular a thermoplastic elastomer, specifically a thermoplastic polyester elastomer (TPEE), which is a polyester copolymer having a high modulus of elasticity. It is thus possible for each bearing part103to be formed integrally with spring blades105projecting from the inside of the bearing part103. In this embodiment, the purpose of the spring blades105is to increase the strength of the element101at the end of the compression stroke, when the spring blades105of the opposite bearing parts103come into contact.

Although the bearing parts103in this first embodiment are adhesively bonded to the ends102a,102bof the compressible core102, they may be fastened using other alternatives. Thus, in a second embodiment shown inFIGS. 2A and 2B, the ends202a,202bof the compressible core202of a cushion or mattress suspension element201are clamped perpendicularly to the compression axis Z by collars203csecured to the inner faces of each of the bearing parts203. Thus, the bearing parts203may be fastened to each of the ends202a,202bof the compressible core202merely by inserting the ends202a,202bin the collars203cof the corresponding bearing parts203. As in the first embodiment, the compressible core202is made of flexible material and may in particular be made by extruding a high resilience flexible synthetic foam, and in particular a polyurethane foam that presents density lying more particularly in the range 30 kg/m3to 150 kg/m3. Nevertheless, in this second embodiment, the cross-section of the compressible core202is round and not cruciform, thereby not only making it easier to fasten the collars203conto its ends, but also making it easier to bend the compressible core202perpendicularly relative to its main axis Z, thus forming a ball-joint type hinge between the bearing parts203.

Around the collars203c, each bearing part203also has through orifices204serving to provide better ventilation of the mattress or cushion. As in the first embodiment, the bearing parts203may be made by injection molding, for example. The material used may, in particular be an elastic material that is natural, such as rubber, or that is synthetic, in particular a thermoplastic elastomer, specifically a thermoplastic polyester elastomer. Spring blades205are also formed projecting from the inside of each bearing part203in order to increase the strength of the element201at the end of the compression stroke, when the spring blades205of each bearing part203come into contact with the opposite bearing part203.

Spring blades may also be arranged so as to be stressed also at the beginning of the compression stroke and not only at the end of the stroke. In a third embodiment shown inFIGS. 3A and 3B, the suspension element301has spring blades305formed integrally with the bearing parts303and interposed between the bearing parts303and the compressible core302. Thus, at either end of the compressible core302, these spring blades305form a spring that is less damped than the compressible core302, and that is connected in series therewith so as to be subjected to the same compression forces.

At either end of the compressible core302, the connection between the spring blades305and the compressible core302is made via an endpiece306that is also formed integrally with the spring blades305and the bearing parts303, and that presents a belt306awith projections306bfor catching the outside surface of the compressible core302, as shown inFIG. 3B. In addition to through orifices304of the same type as those in the first and second embodiments, each of the bearing parts303also presents a large central opening307that is complementary to the outline of the spring blades305and of the endpiece306in a plane extending transversely to the main axis Z, thus making it possible not only to improve ventilation of the cushion or mattress, but also to improve injection molding of the bearing part303, of the spring blades305, and of the endpiece306as a single part in a mold without slides. As in the above-described embodiments, this unit can be made with an elastic material that is natural, such as rubber, or that is synthetic, and in particular a thermoplastic elastomer, specifically a thermoplastic polyester elastomer.

As in the first and second embodiments, the compressible core302is made of flexible material and may in particular be made by extruding a high resilience flexible synthetic foam, and in particular a polyurethane foam, presenting density lying more particularly in the range 30 kg/m3to 150 kg/m3. As in the second embodiment, the cross-section of the compressible core302is round and not cruciform, thereby not only facilitating insertion and fastening of its ends303a,303bin the endpieces306, but also facilitating bending of the compressible core302perpendicularly to the compression axis Z, thus forming a ball-joint type hinge between the bearing parts303.

As an alternative to this series arrangement, it is also possible to envisage an arrangement of the spring in parallel with the compressible core. Thus, in a fourth embodiment shown inFIGS. 4A and 4B, the two bearing parts403of the suspension element401are connected together by the spring blades405with which they are made integrally, e.g. by injection molding. The material used may in particular be an elastic material that is natural, such as rubber, or that is synthetic, in particular a thermoplastic elastomer, specifically a thermoplastic polyester elastomer. In this fourth embodiment, the spring blades405are also connected together by a belt408that transversally clamps an intermediate segment of the compressible core402situated between the ends402a,402b. As in the third embodiment, each bearing part403presents not only through orifices404of the same type as in the first and third embodiments, but also a large central opening407, having the main purpose in this fourth embodiment of allowing the compressible core402to be inserted between the two bearing parts403. After this insertion, closure parts409(shown in dashed lines inFIG. 4B) may be clipped to these central openings407so as to retain the compressible core402in the cushion or mattress suspension element401between the bearing parts403.

As in the above-described embodiments, the compressible core402is made of flexible material and it may in particular be made by extruding a high resilience flexible synthetic foam, and in particular a polyurethane foam presenting density lying more particularly in the range 30 kg/m3to 150 kg/m3. Since the compressible core402connects together the bearing parts403in parallel with the spring formed by the spring blades405, when a compression force moves these bearing parts403towards each other, the compressible core402and the spring blades405are subjected to substantially the same amount of deformation along the compression axis Z. Simultaneously, the belt408that is incorporated in the spring formed by the spring blades405prevents the intermediate segment of the compressible core402from expanding radially, thereby increasing the stiffness of the cushion or mattress suspension element401, while also making it easier for it to bend perpendicularly to the compression axis Z.

In a fifth embodiment, shown inFIG. 5, the compressible core502of the suspension element501is not made of foam but of a hollow elastic material, and it presents a bellows shape. As in the third embodiment, spring blades505formed integrally with the bearing parts503are interposed between the bearing parts503and the compressible core502, so as to form at either end of the compressible core502, a spring that is less damped than the compressible core502, the spring being connected in series with the compressible core502so as to be subjected to the same compression forces as the compressible core502. Each of the bearing parts503presents an outer bearing area503athat is substantially greater than the area of the compressible core502in cross-section relative to the compression axis Z, and through orifices504for improving ventilation of the cushion or mattress.

In a sixth embodiment, shown inFIG. 6A, the compressible core602is elongate along an axis X perpendicular to the compression axis Z, and a plurality of bearing parts603are arranged above and below the compressible core602so as to form the cushion or mattress suspension element601. As in the third embodiment, spring blades605that are formed integrally with the bearing parts603are interposed between these bearing parts603and the compressible core602so as to form above and below the compressible core602springs that are less damped than the compressible core602, which springs are connected in parallel with one another but in series with the compressible core602, so as to be subjected together to the same compression forces as the compressible core602. Each of the bearing parts603presents an outer bearing area603athat is substantially larger than the compressible core602along an axis Y that is perpendicular to the axes Z and X, and through orifices604serving to provide better ventilation of the cushion or mattress.

As in the first and fourth embodiments, the compressible core602is made of flexible material and may in particular be made by extruding a high resilience flexible synthetic foam, and specifically a polyurethane foam, presenting density lying more particularly in the range 30 kg/m3to 150 kg/m3. Nevertheless, in this embodiment, the material is not extruded along the compression axis Z, but along the axis X that is perpendicular thereto. In addition, although the compressible core602of this embodiment as shown inFIG. 6Apresents a solid rectangular cross-section relative to the axis X, it is possible to envisage using other solid or hollow sections as alternatives, such as the sections shown inFIGS. 6B to 6H. It is also possible to envisage using materials other than foams, in particular with sections that are hollow.

In elements701,801in seventh and eighth embodiments, as shown respectively inFIGS. 7 and 8, the compressible core702or802is likewise elongate along an axis X perpendicular to the compression axis Z, and a plurality of bearing parts703or803are arranged above and below the compressible core702,802in order to form the cushion or mattress suspension element701,801. The compressible core702,802is likewise made of flexible material and may in particular be made of extruding a high resilience flexible synthetic foam, and in particular a polyurethane foam presenting density lying more particularly in the range 30 kg/m3to 150 kg/m3. As in the third and sixth embodiments, spring blades705,805formed integrally with the bearing parts703,803are interposed between these bearing parts703,803and the compressible core702,802so as to form above and below the compressible core702,802springs that are less damped than is the compressible core702,802and that are connected in parallel with one another but in series with the compressible core702,802so as to be subjected together to the same compression forces as the compressible core702,802. Above and below each compressible core702,802, the connections between the spring blades705,805and the compressible core702,802are made by means of endpieces706,806that are also made integrally with the spring blades705,805and the bearing parts703,803. Each of the bearing parts703,803thus presents an outer bearing area703a,803athat is substantially larger than the compressible core702,802along an axis Y perpendicular to the axes Z and X, with through orifices704,804providing better ventilation for the cushion or mattress. Nevertheless, in each of these embodiments, the bearing parts703,803above and below the compressible core702,802and adjacent thereto are connected together by flexible connections710,810that allow the elements701,801to bend in the XZ plane. In both of these embodiments, these flexible connections710,810are formed integrally with the bearing parts703,803. Nevertheless, in the seventh embodiment, the flexible connections710are concertina-shaped, whereas in the eighth embodiment, the flexible connections810present a zigzag shape. Furthermore in the seventh embodiment, the width along the axis Y of the compressible core702varies along axis X, so that the core702present zigzag side surfaces.

In a ninth embodiment shown inFIG. 9, a plurality of cushion or mattress suspension elements901are connected together side by side to form an elongate module911. As in the third embodiment, each suspension element901has spring blades905formed integrally with the bearing parts903and interposed between the bearing parts903and the compressible core902. The compressible core902is made of flexible material and may in particular be made by extruding a high resilience flexible synthetic foam, and in particular a polyurethane foam, presenting density lying more particularly in the range 30 kg/m3to 150 kg/m3. At each end of each compressible core902, the connection between the spring blades905and the compressible core902is made via endpieces906that are also formed integrally with the spring blades905and the bearing parts903. Each of the bearing parts903also presents an outer bearing area903athat is substantially larger than the compressible core902along an axis Y perpendicular to the axes Z and X, and through orifices904providing better ventilation for the cushion or mattress. In addition, flexible connections910, likewise in the form of spring blades formed integrally with the bearing parts, connect together adjacent bearing parts903at each end of the compressible cores902.

As can be seen inFIG. 10, cushion or mattress suspension elements101,201,301,401,501, and601of the various embodiments may be incorporated in a mattress1between a bottom face2and a top face3of the mattress1, with the axes Z of the elements being substantially perpendicular to these bottom and top faces2,3. The mattress1may be stuffed with a foam of density that is substantially less than that of the compressible cores102,202,302,402,502,602. Thus, the elements101,201,301,401,501, and601provide a user with spot bearing points, thereby increasing the perceived firmness and the durability of the mattress1, while nevertheless limiting its weight and its cost. Like conventional mattress springs, these cushion or mattress suspension elements may also be bagged in order to protect the stuffing. It is also possible to stack a plurality of these elements along the compression axis Z. Although the various elements102,201,301,401,501, and601inFIG. 10are shown as being incorporated in a mattress, other applications may be envisaged, in particular in cushions, mainly seat cushions. In this context, a seat cushion should be understood as being any element presenting a flexible surface for making sitting comfortable. Thus, such a seat cushion may be independent of or incorporated in a sofa, a chesterfield, a settee, an armchair, etc.

Although the present invention is described above with reference to specific embodiments, it is clear that various modifications and changes can be performed on those examples without going beyond the general ambit of the invention as defined by the claims. In particular, individual characteristics of the various embodiments shown may be combined in additional embodiments. Consequently, the description and the drawings should be considered in a sense that is illustrative rather than restrictive.