Shape-adaptive cushion arrangement for seat devices and mattresses

Abstract

The invention relates to a cushion arrangement (100), and to a seat device (1000) and a mattress (2000) which comprise the cushion arrangement (100). The cushion arrangement (100) has a shape layer (10) made of a polyurethane-based material, wherein the polyurethane-based material comprises a furfuryl-alcohol-functionalised polyurethane and a maleimide-functionalised cross-linking agent. In addition, a controllable heating element (30) is integrated into the shape layer (10) and is designed to supply thermal energy to the shape layer (10). The cushion arrangement (100) also has a thermal insulator layer (20) which is arranged on the shape layer (10) and is designed to thermally insulate the shape layer (10).

Description

[0001] Description

[0002] Shape-adaptive upholstery arrangement for seating and mattresses

[0003] The invention relates to a cushion arrangement, a seating device and a mattress comprising the cushion arrangement.

[0004] Adjustable upholstery systems are found in seating devices such as vehicle seats or treatment chairs, as well as in specialized mattresses for medical or non-medical treatment beds or stretchers. To meet the individual needs of the driver or patient, a variety of mechanical or electromechanical actuators are used to enable the adjustment of lumbar support systems, seat positioning, and seat angles as required. However, these actuators require corresponding control systems and electronics, which, in the case of a vehicle seat, for example, further strain the already limited installation space and increase the vehicle's weight.Furthermore, the adjustment of the upholstery to the individual physical characteristics of the user can only be done to a limited extent and at the same time requires a high level of technical effort, especially in the case of treatment beds for patients with complicated spinal injuries or with diseases that require a demanding lying or sitting position.

[0005] Therefore, non-mechanical solutions, such as the use of shape-memory polymers (SMPs), are coming into focus for the automotive industry. US patent 2005 / 0218710 A1 discloses a vehicle seat arrangement in this context, which incorporates a seat fabric with a shape-memory polymer that causes a change in the stiffness and / or flexibility of the seat fabric via a thermal activation signal. Depending on the polymer, however, the thermal activation signal may fall within a temperature range in which, without sufficient thermal insulation, serious tissue damage to the user's skin can occur.

[0006] The invention is based on the objective of providing a cushion arrangement for seating devices and mattresses that can adapt to the individual body shape of the user and transfers no or at least only a small, harmless amount of heat to the user during the adaptation process.

[0007] A first aspect of the present invention relates to a cushion arrangement. The cushion arrangement comprises a molded layer, a controllable heating element integrated into the molded layer, and a thermal insulation layer arranged on the molded layer. The molded layer comprises a polyurethane-based material comprising a furfuryl alcohol-functionalized polyurethane and a maleimide-functionalized crosslinker. The controllable heating element is integrated into the molded layer and is designed to supply thermal energy to the molded layer (in particular to the polyurethane-based material) in order to achieve a switching temperature of the polyurethane-based material. The thermal insulation layer is arranged (directly) on the molded layer and is designed to thermally insulate the molded layer (e.g., from the vehicle interior or the contact surface with the user).The furfuryl alcohol-functionalized polyurethane and the maleimide-functionalized crosslinker are covalently linked to each other via a temperature-dependent, reversible Diels-Alder reaction. This means that below a certain switching temperature, the furfuryl alcohol-functionalized polyurethane and the maleimide-functionalized crosslinker are covalently linked (via their functional groups), and above this switching temperature, they undergo a reversible retro-Diels-Alder reaction, in which the covalent bonds between the functional groups are at least partially broken.

[0008] In a preferred embodiment of the invention, it is provided that the maleimide-functionalized crosslinker covalently bonded to the furfuryl alcohol-functionalized polyurethane undergoes a reversible retro-Diels-Alder reaction at a switching temperature in the range of 80 °C to 120 °C.

[0009] In a further preferred embodiment of the invention, it is provided that the thermal insulating layer comprises at least one phase-change material (PGM) which has a phase transition temperature in the range of 20 °C to 60 °C and is suitable to store at least part of the supplied thermal energy for reaching the switching temperature of the polyurethane-based material as latent energy through a phase transition (e.g. solid-liquid, liquid-solid).

[0010] Preferably, the thermal insulating layer comprises at least one phase change material having a heat storage capacity of 150 kJ / kg to 260 kJ / kg in the temperature range of 20 °C to 60 °C. The thermal insulating layer may preferably comprise at least one phase change material selected from the following group: unbranched and branched alkanes (paraffins), unsaturated hydrocarbons, halogenated hydrocarbons, alicyclic hydrocarbons, hydrated salts, saturated and unsaturated fatty acids, fatty acid esters, fatty alcohols, anhydrides, ethylene carbonate, polyhydric alcohols, sugar alcohols, and polymers. Phase change materials selected from unbranched and branched alkanes (paraffins) and hydrated salts are particularly preferred.

[0011] In a preferred embodiment of the invention, the thermal insulating layer comprises a polymer matrix that encloses the phase-change material described above and is arranged (directly) on the mold layer. In other words, the mold layer is coated on one side (or both sides) with the thermal insulating layer and can thus protect the user from harmful heat radiation from the controllable heating element.

[0012] The polymer matrix can be a polymer foam, preferably a polyurethane foam. The percentage by weight of the phase change material in relation to the total weight of the phase change material and polymer matrix is ​​preferably 10 to 40 wt.%.

[0013] Preferably, the phase change material can be present in (micro-)encapsulated form and uniformly distributed within the thermal insulating layer. In other words, one or more phase change materials are present in (micro-)encapsulated form and are uniformly dispersed (i.e., distributed without forming chemical bonds with the polymer matrix) within the polymer matrix of the thermal insulating layer.

[0014] The controllable heating element can be designed as an electrical heating element (e.g., in the form of heating wires, heating coils, heating meshes, or the like) and can be integrated (embedded) in the mold layer or the polyurethane-based material. This allows for low heat loss during heat transfer to the polyurethane-based material.

[0015] A second aspect of the present invention relates to a seating device. The seating device comprises a seat, a backrest, and may optionally include a headrest. One embodiment of the upholstery arrangement described above is arranged in one or more separate areas of the seat. Furthermore, one embodiment of the upholstery arrangement described above may additionally be arranged in one or more areas of the backrest.

[0016] The seating device may also include a control unit designed to activate the controllable heating element of one or more upholstery arrangements independently of each other.

[0017] The seating device described above can be designed as a vehicle seat or a (medical) treatment chair.

[0018] Another aspect of the present invention is a mattress, wherein an embodiment of the upholstery arrangement described above is arranged in one area or in several separate areas of the mattress. The mattress can also include a control unit designed to activate the controllable heating element of one or more upholstery arrangements independently of one another.

[0019] Unless otherwise stated in individual cases, the various embodiments of the invention mentioned in this application can be advantageously combined with one another.

[0020] The invention is explained below using exemplary embodiments with reference to the accompanying drawings. These show:

[0021] Figure 1 shows a schematic representation of an embodiment of the upholstery arrangement, exemplified in two areas of a vehicle seat.

[0022] Figure 2 shows a schematic representation of a seating device according to the invention with

[0023] Seat surface, backrest and headrest as well as an embodiment of the upholstery arrangement according to the invention, which is arranged in several separate areas of the seating device.

[0024] Figure 3 shows a schematic representation of a mattress according to the invention, comprising an embodiment of the upholstery arrangement according to the invention, which is arranged in several separate areas of the seating device.

[0025] Figure 1 shows an embodiment of the cushion arrangement 100 in exemplary use, here in a vehicle seat. The cushion arrangement 100 comprises a film-like molded layer 10 and a thermal insulating layer 20 arranged on the molded layer. The molded layer 10 is coated with the thermal insulating layer 20 on at least one side over its entire surface. As shown in Figure 1, at least that area of ​​the molded layer 10 facing the contact surface of the cushion arrangement with the user is coated with the thermal insulating layer 20.

[0026] The cushion arrangement 100 also includes a controllable heating element 30, which is integrated (embedded) in the mold layer 10 and is designed to supply thermal energy to the mold layer (in particular, the polyurethane-based material). As indicated in Figure 1, the controllable heating element 30 can be designed as an electrical heating element in the form of heating wires embedded in the polyurethane-based material and thus in direct contact to enable effective heat transfer to the polyurethane-based material. The controllable heating element 30 is preferably activated and deactivated via a control unit 32, e.g., an electrical switch or controller.

[0027] The thermal insulating layer 20 serves to thermally insulate the mold layer 10 and prevents harmful heat radiation generated by the heating element 30 from reaching the contact surface with the user.

[0028] The upholstery assembly 100 can further comprise an upholstery body that encloses the molded layer 10 and the thermal insulation layer 20. The upholstery assembly 100 can also comprise at least one further upholstery layer arranged on the thermal insulation layer 20. This upholstery layer can comprise standard upholstery materials, such as polyurethane foam, polyether foam, or polyester foam. The upholstery body, which encloses the molded layer 10, the thermal insulation layer 20, and also the optional upholstery layer, can be covered with a material such as a synthetic fabric or leather, on which the user sits or lies directly.

[0029] The mold layer 10 can preferably have a layer thickness of 1 mm to 200 mm.

[0030] The thermal insulating layer 20 can preferably have a layer thickness of 1 mm to 200 mm.

[0031] Figure 2 shows an embodiment of a seating device 1000 according to the invention. The seating device 1000 has a seat surface 50, a backrest 60, and optionally a headrest 70. As shown, a plurality of upholstery arrangements 100 according to the invention can be arranged in several separate areas of the seat surface 50, the backrest 60, and optionally in the headrest 70, and can be controlled via a common control unit 32. The seating device 1000 can also have several control units 32, each of which independently controls one upholstery arrangement from a plurality of upholstery arrangements. In an alternative embodiment of the seating device 1000, the upholstery arrangement 100 extends continuously from the seat surface 50 over the backrest 60.

[0032] Figure 3 shows an embodiment of a mattress 2000 according to the invention, in which a plurality of upholstery arrangements 100 according to the invention are arranged in several separate areas and are controlled via a common control unit 32. Alternatively, a single upholstery arrangement 100 can be arranged over the entire lying surface of the mattress.

[0033] The mold layer 10 comprises or consists of a polyurethane-based material comprising a furfuryl alcohol-functionalized polyurethane and a maleimide-functionalized crosslinker. Preferably, the polyurethane-based material has a switching temperature of 80 °C to 120 °C, particularly preferably 85 °C to 100 °C. The switching temperature can be determined by differential scanning calorimetry (DSC) during heating cycles from 25 °C to 120 °C at a heating rate of 10 K / min (e.g., according to DIN EN ISO 11357). The switching temperature is detectable as a change in heat flow in the range between 80 and 120 °C.

[0034] Below the switching temperature, the maleimide-functionalized crosslinker is covalently bonded to the furfuryl alcohol-functionalized polyurethane via their functional groups (maleimide and furfuryl alcohol), forming a dimensionally stable mold layer. Above the switching temperature, the covalent bonds between the maleimide-functionalized crosslinker and the furfuryl alcohol-functionalized polyurethane break, resulting in a flowable (deformable) mold layer. In other words, the maleimide groups react with the furfuryl alcohol groups in a temperature-dependent and reversible [4+2] cycloaddition (reversible Diels-Alder reaction). The switching temperature corresponds to the reaction temperature at which the retro-Diels-Alder reaction (or [4+2] cycloelimination) proceeds, yielding unbound furfuryl alcohol-functionalized polyurethane and the maleimide-functionalized crosslinker.If the temperature drops below the switching temperature, the unbound furfuryl alcohol-functionalized polyurethane and the maleimide-functionalized crosslinker react in a Diels-Alter reaction to form the [4+2] cycloaddition product. The degree of crosslinking of the polyurethane-based material is therefore lower above the switching temperature than below it. The mold layer 10 thus becomes reversibly deformable upon heating, enabling individual adaptation of the cushion arrangement to the user. The furfuryl alcohol-functionalized polyurethane is a copolymer made from furfuryl alcohol, at least one polyisocyanate, and at least one polyol. Suitable polyisocyanates include, for example, diisocyanates and triisocyanates. Suitable polyols include, for example, polyether polyols and diols.

[0035] The maleimide-functionalized crosslinker comprises at least two maleimide groups.

[0036] The thermal insulating layer 20 preferably comprises at least one phase-change material (PCM) having a phase transition temperature in the range of 20 °C to 60 °C and being capable of storing at least a portion of the supplied thermal energy required to reach the switching temperature of the polyurethane-based material as latent energy through a phase transition (e.g., solid-liquid or liquid-solid, but preferably solid-liquid). The phase transition temperature is preferably in the range of 35 °C to 60 °C, more preferably in the range of 40 °C to 60 °C, and particularly preferably in the range of 35 °C to 58 °C. The thermal insulating layer 20 may additionally comprise one or more further phase-change materials having a phase transition temperature in a higher range of 60 °C to 130 °C to further improve the thermal insulation.

[0037] A phase change material (PCM) is a substance that requires a high enthalpy of fusion to effect a phase transition, e.g., from the solid to the liquid state. It therefore has the property of absorbing large amounts of thermal energy, known as latent heat, and releasing it again during the reversible phase transition. During the phase change, the temperature of the PCM remains essentially constant. The phase transition temperature corresponds to the temperature at which the phase transition of the PCM begins and latent heat is stored.

[0038] The phase-change material preferably has a heat storage capacity of 150 kJ / kg to 260 kJ / kg in the range of 20 °C to 60 °C. The heat storage capacity can be determined by 3-layer calorimetry.

[0039] The selection of the phase change material is not limited by its chemical composition, provided that the phase change material has a phase transition temperature in the range of 20 °C to 60 °C and / or a heat storage capacity of 150 kJ / kg to 260 kJ / kg in the range of 20 °C to 60 °C. The selection of the optional additional phase change material is also not limited by its chemical composition, provided that it has a phase transition temperature in the range of 60 °C to 130 °C and / or a heat storage capacity of 150 kJ / kg to 260 kJ / kg in the range of 60 °C to 130 °C.

[0040] The phase change material does not exist as a gas in the temperature range of -20 °C to 500 °C. Under normal conditions, the phase change material preferably exists primarily as a solid.

[0041] Examples of phase-change materials include unbranched and branched alkanes (paraffins), unsaturated hydrocarbons (e.g., alkenes, alkynes, and arenes), halogenated hydrocarbons, and alicyclic hydrocarbons. Particularly favored examples of these classes include n-heneicosane, n-eicosane, n-nonadecane, n-octadecane, and n-heptadecane, as well as mixtures thereof. Another example of a phase-change material is silicone wax.

[0042] Preferred phase-change materials may also include hydrated salts. Suitable hydrated salts include: calcium chloride hexahydrate, calcium bromide hexahydrate, magnesium nitrate hexahydrate, lithium nitrate trihydrate, potassium fluoride tetrahydrate, ammonium alum, magnesium chloride hexahydrate, sodium carbonate decahydrate, disodium phosphate dodecahydrate, sodium sulfate decahydrate, and sodium acetate trihydrate.

[0043] Preferred phase-change materials may also include saturated and unsaturated fatty acids, fatty acid esters, and fatty alcohols. Suitable saturated and unsaturated fatty acids include: caproic acid, caprylic acid, lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, behenic acid, lignoceric acid, and cerotic acid. Suitable fatty acid esters include: fatty acid C1-C4 alkyl esters, preferably selected from the group comprising: methyl caprylate, methyl caprate, methyl laurate, methyl myristate, methyl palmitate, metal stearate, methyl arachidate, methyl behenate, and methyl lignocerate. Suitable fatty alcohols include: caprylic alcohol, lauryl alcohol, myristyl alcohol, cetyl alcohol, stearyl alcohol, arachidyl alcohol, behenyl alcohol, lignoceryl alcohol, ceryl alcohol, montanyl alcohol, and myricyl alcohol.

[0044] Other examples of phase-change materials include anhydrides (e.g., stearic anhydride), ethylene carbonate, polyhydric alcohols (e.g.,

[0045] 2,2-Dimethyl-1,3-propanediol, 2-hydroxymethyl-2-methyl-1,3-propanediol, ethylene glycol, polyethylene glycol, pentaerythritol, dipentaerythritol, pentaglycerin, tetramethylol-ethane, neopentyl glycol, tetramethylolpropane, 2-amino-2-methyl-1,3-propanediol, Monoaminopentaerythritol, diaminopentaerythritol and tris(hydroxymethyl)acetic acid), sugar alcohols (e.g. erythritol, D-mannitol, galactitol, xylitol, D-sorbitol).

[0046] Other examples of phase change materials include polymers selected from the group comprising: polyethylene, polyethylene glycol, polyethylene oxide, polypropylene, polypropylene glycol, polytetramethylene glycol, polypropylene malonate, polyneopentyl glycol sebacate, polypentane glutarate, polyvinyl myristate, polyvinyl stearate, polyvinyl laurate, polyhexadecyl methacrylate and polyoctadecyl methacrylate.

[0047] The thermal insulating layer 20 may preferably comprise one of the following phase change materials from Rubitherm Technologies GmbH: RUBITHERM®RT54HC, RUBITHERM®RT55 and RUBITHERM®SP58.

[0048] The thermal insulating layer 20 can additionally include one or more of the following phase change materials from Rubitherm Technologies GmbH: RUBITHERM®RT62HC, RUBITHERM®RT64HC, RUBITHERM®RT65, RUBITHERM®RT69HC, RUBITHERM®RT70HC, RUBITHERM®RT80HC, RUBITHERM®RT82, RUBITHERM®RT90HC, RUBITHERM®RT100HC, RUBITHERM®RT111HC and RUBITHERM®RT125.

[0049] Reference symbol list

[0050] 100 cushion arrangement

[0051] 10 Form layer

[0052] 20 thermal insulator

[0053] 30 controllable heating elements

[0054] 32 Control unit

[0055] 1000 Seating device

[0056] 50 Seating area

[0057] 60 Backrest

[0058] 70 Headrest

[0059] 2000 mattress

Claims

Patent claims 1. Cushion arrangement (100) comprising: a molded layer (10) with a controllable heating element (30) integrated into the molded layer (10) and configured to supply thermal energy to the molded layer (10); and a thermal insulating layer (20) arranged on the molded layer (10) and configured to thermally insulate the molded layer (10); wherein the molded layer (10) comprises a polyurethane-based material comprising a furfuryl alcohol-functionalized polyurethane and a maleimide-functionalized crosslinker, which are covalently linked to each other in a temperature-dependent manner by a reversible Diels-Alder reaction.

2. Cushion arrangement (100) according to claim 1, wherein the maleimide-functionalized crosslinker covalently bonded to the furfuryl alcohol-functionalized polyurethane undergoes a reversible retro-Diels-Alder reaction at a switching temperature in the range of 80 °C to 120 °C.

3. Cushion arrangement (100) according to one of claims 1 or 2, wherein the thermal insulating layer (20) comprises at least one phase change material having a phase transition temperature in the range of 20 °C to 60 °C and being suitable to store at least a part of the supplied thermal energy to achieve the switching temperature of the polyurethane-based material as latent energy through the phase transition.

4. Cushion arrangement (100) according to one of the preceding claims, wherein the thermal insulating layer (20) comprises at least a phase change material having a heat storage capacity of 150 kJ / kg to 260 kJ / kg in the range of 20 °C to 60 °C.

5. Cushion arrangement (100) according to one of the preceding claims, wherein the thermal insulating layer (20) comprises at least one phase change material selected from the group comprising: unbranched and branched alkanes (paraffins), unsaturated hydrocarbons, halogenated hydrocarbons, alicyclic hydrocarbons, hydrated salts, saturated and unsaturated fatty acids, fatty acid esters, fatty alcohols, anhydrides, ethylene carbonate, polyhydric alcohols, sugar alcohols and polymers.

6. Cushion arrangement (100) according to one of claims 3 to 5, wherein the thermal insulating layer (20) comprises a polymer matrix enclosing the phase change material.

7. Cushion arrangement (200) according to claim 6, wherein the phase change material is present in encapsulated form and uniformly distributed in the thermal insulating layer (20).

8. Seating device (1000) comprising: a seat surface (50), a backrest (60) and optionally a headrest (70); wherein the upholstery arrangement (100) according to one of the preceding claims is arranged in one or more areas of the seat surface (50).

9. Seating device (1000) according to claim 8, wherein the seating device is a vehicle seat.

10. A mattress (2000) wherein the padding arrangement (100) according to any one of claims 1 to 7 is arranged in one or more areas of the mattress (2000).

Images