EP1348316B1 - Surface heating device, method for producing the same and heatable object - Google Patents

Description

The invention relates to a surface heating according to the preamble of claim 1 and a heatable object with such a surface heating and method for producing a surface heating.

In particular, the present invention relates to a seat heating, a heated seat and method for their preparation. Preferably, the invention also relates to a heater for side panels and floor coverings, especially in vehicles, side panels and floor coverings equipped therewith, in particular in vehicles, and methods for their production. Furthermore, the present invention relates in particular to a mattress heater, a heated mattress and methods for their production.

From practice, for example, seat heating systems are known for motor vehicles, which constitute a surface heating in the context of the invention and are formed by current-carrying metallic lines as heating wires, which are arranged between cushioning layers. This not only requires a complex construction of a suitably equipped seat, but has disadvantages especially in operation. Thus, due to the increased heating of surrounding layers in the immediate vicinity of the heating wires, there is a risk of overheating, which can lead to damage to the cushioning layers and / or the heating wires and even cause a fire. Furthermore, the heat distribution over the surface is not optimal, since in the region of the heating wires, the temperature is always higher than at a distance thereof. A disadvantage of this known construction is also the mechanical stress to which the heating wires are exposed when an occupant uses the seat, as this can break the conductor wires, which can lead to functional failure and / or has another source of fire result.

From the DT 26 16 771 A1 For example, a composite heater is known that provides directional thermal radiation and is formed from a plastic laminate incorporating a semiconducting layer. This laminate consists of a rigid plastic laminate structure composed of at least one layer of reinforced substrate base material and a resin coating on this material, a semiconducting carbonaceous pyropolymer bonded to a high surface area, refractory inorganic oxide support which acts as a layer on at least one side of the layer of the substrate material, a heat reflecting layer incorporated in a position on one side of the pypolymer on the substrate material, and power supply means being formed to spaced apart portions of the layer of conductive carbonaceous pyropolymer and generating electrical resistance heating in the laminate formed by the heat reflecting layer of the assembled body is reflected and emitted. Such heating plates should be used as part of a wall of a living room or office.

In this prior art, the incorporation of the semiconductive layer into the laminate can be accomplished by mixing finely divided carbonaceous pyropolymer in the form of small particles or as a powder with a suitable vehicle or vehicle so that it will reside on the surface of a resin-coated glass cloth Paper, felt, cardboard and the like as a laminate substrate or on a wood veneer which may be used in the laminate board, spread, spread or otherwise applied. Instead, the finely divided carbonaceous pyropolymer may also be mixed with the resin or polymer material with which a particular reinforcing base material is to be impregnated or applied to this base material as a coating, this base material providing at least one substrate layer of the laminate. The resulting Mixture is applied in or onto the substrate by dipping or coating, and the resulting coated substrate is subjected to a semi-cure such that the semiconducting pyro-polymer results in uniform impregnation and coating over the resulting semi-cured laminate sheet.

The DE 33 16 182 A1 is concerned with the use of shaped articles, such as films, sheets or spatially shaped structures, of the class of pyrrole polymers complexed with anions, as electrical heating elements, in particular for heating corrosive liquids or gases. The moldings may still be coated with organic plastics.

A polymeric composite heating element is in the DE 35 24 631 A1 described and has the form of a film, tube or rod. Such polymeric composite heating elements can be used as such as heating sources or laminated with conventional plastic films to improve the material thickness.

The use of electrically conductive thermoplastic polyurethanes and their preparation are known from DE 33 21 516 A1 known. Corresponding products are suitable, inter alia, for the production of 1 to 2 mm thick films for surface heating elements.

Thus, while generally heating devices are known with electrically conductive plastic, however, the entire state of the art contains no information or suggestions on how such heaters must be equipped and manufactured in order to be used in practice can.

In a number of other publications of the international patent classes H05B 3/36 and 3/84 surface heating are explained by examples of exterior mirrors for motor vehicles, which have a layer of electrically conductive plastics. Essentially, films of electrically conductive Plastics used on rigid supports. A use of a film of electrically conductive plastics on the support structure of a motor vehicle seat, however, is not possible because then the entire overlying cushioning layers, etc. would have to be heated until the heat would come to a seated occupant, which would consume a lot of energy.

Especially for sitting or lying documents no useful surface heating with electrically conductive plastics have become known. However, for example, motor vehicle seats or mattresses would be simple, inexpensive and reliable heaters desirable.

The DE 2 148 191 A discloses wireless panel heaters and methods of making the same. These wireless surface heating elements consist of a fabric laminated on one side and a plastic layer applied to the non-laminated side of the fabric, wherein the non-laminated side of the fabric is treated with an aqueous dispersion of electrically conductive particles containing plastic dispersion and electrical electrodes and corresponding electrical connections was provided.

From the US 3,768,156 a method for the production of electrical heating panels for textile articles is known. The method includes coating a blank of textile material with an electrically conductive polymer to form a flexible electrically conductive resistive element, disposing two continuous electrodes of a braided electrical conductor on the element, wherein a major portion of one of the electrodes is in spaced parallel relationship to a major part of the other electrode is which electrodes are waved to form electrically conductive paths between the electrodes and over a major part of the element, attaching the electrodes to the element by means of an axial series of stitches through each electrode, and the electrical Isolating the electrodes from each other, where they intersect or lie adjacent, through strips of insulation material.

A flexible heating element is in the WO 90/09086 disclosed. It contains a flexible substrate, on top of which is a layer of electrically conductive material to generate heat by conducting an electric current. Two copper strip electrodes are used to apply an electrical current to the conductive material. Each electrode is connected to the conductive material by means of a polymer-based adhesive. The conductive material facing surface of each electrode is embossed to have protrusions that penetrate into the adhesive layer to enhance electrical contact between the electrode and the conductive material.

The GB 2 285 729 A discloses improvements concerning electrically conductive material. A conductive member usable as a resistance heater includes a carbonized fabric having electrical terminals connected thereto and is enclosed in or sandwiched between layers of insulating plastic material. The element is generally flexible and can be designed, for example, as blankets for animals, vehicle seats and clothing. It is preferably provided with electrical control circuitry to control the temperature to which the fabric is heated.

From the EP 1 764 244 A2 is a self-regulating flexible heater known for automobiles and other vehicles. The heater consists of an air-permeable fabric substrate to which a coating of a conductive material and a coating of a material having a positive temperature coefficient is applied.

A surface heater is from the EP 1 602 302 A2 known. This device contains a carrier that is flexible a heater including a conductor and disposed on the carrier, the heater including a first heater disposed in an outer region of the carrier and a second heater parallel to the first heater in an inner region of the carrier is arranged coupled.

It is therefore an object of the present invention, with the least possible effort a well-functioning surface heating with an electrically conductive plastic and an object to create it.

This object is achieved with a surface heating according to claim 1, a heatable article according to claim 15 and a method for producing a surface heating in each case according to claims 22, 24 and 31.

As further advantages, the invention enables a good, simple and reliable design and good heat distribution.

According to the invention, a surface heating is provided with a carrier and a heating layer which contains electrically conductive plastic, wherein the heating layer is formed by a flexible film and the carrier is flexible.

Such surface heating is further developed in the context of the present invention in that the carrier is a layer, in particular a fabric or a fleece, preferably a natural or synthetic nonwoven fabric. Alternatively, the carrier may be a molding made of an elastic material, such as a seat pad of a seat portion or a backrest, or a mattress.

Preferably, the heating layer contains polyurethane, one-component polyurethane, crosslinked one-component polyurethane, a PU foam, UV-resistant and / or hydrolyzable or vapor-permeable plastic material. However, other electrically conductive or conductive foaming and foaming materials may be used, with plastic materials being preferred. Alternatively or additionally, it is preferred that the electrically conductive plastic of the heating layer contains graphite, preferably in powder form.

In the surface heating can be further provided that contact ends of power supply wires in the heating layer or between the carrier and the heating layer are in contact with the latter. Preferably, the contact ends of the power supply wires are fastened by means of the heating layer itself to the latter or sewn or glued to the heating layer and / or the carrier.

Furthermore, it is provided with preference that the heating layer is formed directly by spraying, rolling or brushing on the support. Alternatively, the heating layer may be glued, sewn or welded or otherwise attached to the carrier.

With preference, a manually and / or electrically / electronically actuated and / or automatic current control is further provided, which is connectable to a power source and are connected to the power supply wires whose contact ends are in contact with the heating layer.

The invention also provides a heatable article which incorporates surface heating according to the above embodiments.

Within the scope of a preferred embodiment, the object is a seat surface part or a backrest or a cushion of a sitting or lying furniture, in particular a mattress, and the heating layer is anatomically adapted to thigh buttocks or back parts of a user. The latter is advantageously achieved in that the heating layer in the plane of the seat surface part or the backrest or the upholstery of a sitting or lying furniture, in particular a mattress, is anatomically shaped by being present only according to anatomical specifications or electrically conductive. Alternatively or additionally, the heating layer may have a corresponding thickness profile for anatomically adapted heat release.

Another preferred embodiment of the heatable article consists of a padded lining, in particular of a vehicle. Such a heatable object can also be designed to have a different heat output over its surface.

In general, it can further be provided that the heating layer is profiled in its areal distribution and / or in its thickness for dissimilar heat dissipation over its surface.

Finally, the present invention also provides methods for producing a surface heating, wherein a heating layer with electrically conductive plastic is connected to a carrier. According to the invention, the heating layer is formed by first applying an electrically conductive, in particular foaming or foam plastic material to the carrier and then curing the plastic material on the carrier. A preferred development of this method is that prior to the application of the electrically conductive, in particular foaming or foam plastic material on the carrier first contact ends of power supply wires are arranged on the side of the carrier on which then the plastic material is applied.

Alternatively, in a method according to the invention for producing a surface heating, wherein a heating layer with electrically conductive plastic is connected to a carrier, it is provided that the heating layer consists of an electrically conductive, in particular foaming or foam plastic material and then placed on the carrier. In this case, preferably, the heating layer after arranging on the carrier with the latter can be connected slip-proof. This preferably takes place in that the heating layer is sewn to the carrier, glued or welded.

With preference, but without limitation, the plastic material used is electrically conductive polyurethane.

The method may be further developed by attaching contact ends of power supply wires to the heating layer and / or the carrier so that they are in contact with the latter in the composite of carrier and heating layer. For this purpose, the contact ends of power supply wires are preferably sewn or glued to the heating layer and / or the carrier.

Another development of the method according to the invention is that the heating layer is profiled during or after its production in its surface shape and / or thickness.

When the heating layer is produced, this can be done directly on the carrier, for example by means of templates which determine the surface shape of the heating layer. If the heating layer is made separately, i. not directly on the support, so its shape can be obtained, for example, in shaping frame or by punching. The thickness can also be varied over the surface of the heating layer.

Preferred and advantageous developments emerge from the dependent claims and their combinations as well as the entire disclosure content of these documents, incorporating expert knowledge and the prior art, in particular as far as it is specified in the introduction of this description.

For example, the electrically conductive plastic material of the heating layer may contain carbon or carbon particles to provide electrical conductivity. Moreover, the material of the heating layer is such that it at least substantially cured during or after an increase in temperature as a result of the heating effect and also remains dimensionally stable and undamaged. Polyurethane (PU) is, as already mentioned, preferably used for the electrically conductive plastic, but in principle all other materials disclosed in the prior art mentioned at the outset can be used as far as they can be foamed. Further material and technical background are for example in the publications DE G 85 23 328.5 . DE 298 08 842 Ul . DE 197 11 522 A1 and DE 691 01 703 T2 disclosed, the contents of which are hereby incorporated by reference in its entirety in the present documents to avoid mere reproduction.

Fig. 1a und b

schematisch in einer geschnittenen bzw. perspektivischen teilweisen Ansicht ein erstes Ausführungsbeispiel der Erfindung in Verbindung mit einem Kraftfahrzeugsitz mit einer Sitzheizung,

Fig. 2a und b

schematisch in einer geschnittenen bzw. perspektivischen teilweisen Ansicht einen Kraftfahrzeugsitz mit einer Sitzheizung nach dem Stand der Technik,

Fig. 3a, 3b und 3c

ein zweites und ein drittes Ausführungsbeispiel eine erfindungsgemäßen Flächenheizung schematisch in einer perspektivischen Übersichtsdarstellung bzw. je einer Schnittansicht in Verbindung mit einer Innenauskleidung eines Kraftfahrzeuges,

Fig. 4a und 4b

schematisch eine Innenauskleidungsbezug eines Kraftfahrzeuges als viertes Ausführungsbeispiel einer Flächenheizung in einer perspektivischen Übersichtsdarstellung bzw. einer Schnittansicht,

Fig. 5a und 5b

schematisch ein fünftes Ausführungsbeispiel eines Gegenstandes mit einer Flächenheizung in einer perspektivischen Übersichtsdarstellung bzw. einer Schnittansicht in Form eines Bodenbelages eines Kraftfahrzeuges, und

Fig. 6

schematisch als sechstes Ausführungsbeispiel der Erfindung in einer perspektivischen teilweisen Ansicht einen Kraftfahrzeugsitz mit einer Sitzheizung.

The invention will be explained in more detail below with reference to exemplary embodiments, which are illustrated in the drawings, in which:

Fig. 1a and b

1 is a schematic perspective view of a first embodiment of the invention in conjunction with a motor vehicle seat with seat heating, FIG.

Fig. 2a and b

1 is a schematic perspective view of a motor vehicle seat with a seat heater according to the prior art;

Fig. 3a, 3b and 3c

a second and a third embodiment of a surface heating according to the invention schematically in a perspective overview representation or ever a sectional view in conjunction with an inner lining of a motor vehicle,

Fig. 4a and 4b

2 schematically shows an interior lining cover of a motor vehicle as a fourth exemplary embodiment of a surface heating in a perspective overview or a sectional view;

Fig. 5a and 5b

schematically a fifth embodiment of an article with a surface heating in a perspective overview or a sectional view in the form of a floor covering of a motor vehicle, and

Fig. 6

schematically as a sixth embodiment of the invention in a perspective partial view of a motor vehicle seat with a seat heater.

In the following description of the invention by means of embodiments, the same reference numerals are used throughout for the same or equivalent parts.

Although not all details of the graphical representations are treated in the following description, the individual features and their relationships, as far as they are shown in the figures, readily apparent to those skilled in the figures from the figures themselves.

As the first embodiment of a surface heating 1 is in the Fig. 1a and 1b in a sectional or perspective schematic drawing of a motor vehicle seat 2 shown in the seat part 3, a seat heater 4 is integrated.

The structure of the seat part 3 in the vicinity of the surface heating 1 is in the Fig. 1a in which a cross-section through the respective layers / components of the seat surface part 3 is shown. The surface of the seat part 3 is formed by a seat cover 5, which may be made of fabric, imitation leather or leather or other suitable materials or combinations thereof. The shape of the seat part 3 is formed at least substantially by an elastic foam molded body 6. Between the elastic foam molded body 6 and the seat cover 5, the components of the seat heating 4 are arranged.

The seat heater 4 is formed by the surface heating 1, which contains a heating layer 7 and a carrier 8. The carrier 8 is a flexible layer of a non-woven fabric with natural and / or synthetic fibers. The heating layer 7 consists of a flexible, electrically conductive plastic foam, such as electrically conductive polyurethane, from which a film or a film is formed, so that there is a surface skin. The film has no recognizable pores, but may also be closed-cell or porous in its microstructure. In particular, the material is UV-resistant and / or hydrolyzable or vapor-permeable in order to find use in a seat or couch cushion according to the most preferred application. This ensures optimal air conditioning through the pad for the user.

The material for forming the film, such as UV-resistant and hydrolyzable or vapor-permeable, cross-linked one-component polyurethane, for example, applied by spraying to the nonwoven fabric, so that a so-called spray flush or a spray skin is formed by this so-called spray flushing process. Alternatively, the film could also be formed on the seat cover 5 or the elastic foam molded body 6 by this method. The material could also be sprayed into the foam mold for the elastic foam molded body 6 prior to introduction of the foam material therefor to connect with the latter as it hardens. When the film is produced by spraying, the thickness of the film can be adjusted very accurately, for example by the duration of spraying, and optionally varied over its course. Alternatively, the film can also be produced by rolling or brushing the corresponding material, in particular on the carrier 7, but also separately and then optionally connected to the carrier 7, the seat cover 5 or the elastic foam molded body 6.

Between the heating layer 7 and the carrier 8 7 contact ends 9 and 10 of power supply wires 11 and 12 are inserted at the edge of the heating layer so that they are in electrically conductive contact with the heating layer 7 (see also Fig. 1b ).

To produce the surface heating 1 of the first embodiment is still flowable or liquid electrically conductive polyurethane material containing carbon particles, for example, as already explained above, applied by rolling, brushing or spraying on the nonwoven fabric of the carrier 8, after the contact ends 9 and 10 of the power supply wires 11 and 12 were suitably placed on the nonwoven fabric of the carrier 8. After curing of the electrically conductive polyurethane foam is this flexible and in electrically conductive contact with the contact ends 9 and 10 of the power supply wires 11 and 12 and forms the heating layer 7. The contact ends 9 and 10 of the power supply wires 11 and 12 alone by the composite forces be held between the polyurethane foam and the nonwoven fabric. To further secure the fixation, the contact ends 9 and 10 of the power supply wires 11 and 12 can still be sewn to the composite (not shown). In this variant, the electrically conductive PU layer of the heating layer 7 also represents an adhesive or adhesive layer.

Instead of forming the heating layer 7 directly on the nonwoven fabric of the carrier 8, the heating layer 7 may also be formed separately be combined and in the cured, but flexible state with the carrier 8. The fixation between the heating layer 7 and the carrier 8 takes place for example by gluing, sewing or welding, depending on which processing can be carried out depending on the materials used. The contact ends 9 and 10 of the power supply wires 11 and 12 need not necessarily lie between the carrier 8 and the heating layer 7, but can also be brought together on the side facing away from the carrier 8 of the heating layer 7 with the latter to obtain an electrically conductive contact.

The nonwoven fabric of the carrier 8 may also initially be a strip material, formed on the entire surface or according to the geometry required for the seat part 3, the heating layer 7 or formed thereon the prefabricated heating layer 7 as a strip material or as required for the seat part 3 geometry Parts are placed and connected. Thereafter, the desired individual pieces can be prepared according to the geometry required for the seat part 3, for example by punching. However, it is also possible first to produce the nonwoven fabric in the geometry required for the seat part 3 and then to form the heating layer 7, which may also be prefabricated beforehand according to the geometry required for the seat part 3. The contact ends 9 and 10 of the power supply wires 11 and 12 can be suitably interposed in the manufacture of the composite of carrier 8 and heating layer 7 respectively or arranged on the at least assembled composite for suitable attachment.

In the Fig. 1b is a schematic perspective view of the first embodiment of the surface heating 1, omitting the seat cover 5 further illustrated. The course of the contact ends 9 and 10 of the power supply wires 11 and 12 is also clearly visible. Furthermore, one is Current control 13 and a current source 14 for controlling or for the operation of the surface heating 1 shown schematically. The current controller 13 may be manually and / or electrically / electronically actuated and / or automatic. In practice, the current control 13 is the usual control of the temperature control of the vehicle interior or a part thereof, or a separate control. The power supply wires 11 and 12 are connected to the current controller 13 and quasi end in their contact ends 9 and 10. Before the contact ends 9 and 10, for example, a functional unit 15 may be provided to the power supply wires 11 and 12, for example, a separate seat occupancy sensor, a Heat sensor or temperature sensor, a distributor and more may include.

The carrier 8 could also be formed of other materials and structures, such as a fabric instead of a nonwoven fabric. The support 8 could also be a molded part, such as the elastic foam molded body 6 of the first embodiment according to the Fig. 1a and 1b even.

Suitable materials for the heating layer, i. the electrically conductive foam material, are specified in the present documents, in particular with regard to their physical properties and otherwise well known in the art and, for example, in the prior art, which is cited in the present documents, so it need not be discussed in more detail, but hereby incorporated by reference, all suitable materials, in particular from the older publications cited or referenced herein, are incorporated herein.

Although not explained above and also in the Fig. 1b not shown, can also be found in the Fig. 1b only partially visible backrest 16 may be equipped with a surface heating 1. Furthermore, without limitation, all similar Objects, in particular mattresses or other upholstery, may be equipped with a surface heating system 1 according to the invention. Preference is also an application of the invention in side panels and floor coverings, especially in motor vehicles.

Only to illustrate the differences of the present invention to the prior art, the Fig. 2a and 2b Representations analogous to the Fig. 1a or 1b. This known surface heating 1 in the form of a seat heater 4 for a motor vehicle seat 2 has the seat cover 5 and an elastic foam molded body 6 in a conventional manner, between which the surface heating 1 is located.

In the prior art, the surface heating 1, like the Fig. 2a illustrates, viewed from the seat cover 5 in sequence, an upper fabric layer 17, an upper foam layer 18, a Heizdrahtlage 19, a lower foam layer 20 and a lower fabric layer 21, as a prefabricated composite means of a double-sided adhesive tape 22 with the actual seat cushion forming Foam molded body 6 are connected at least non-slip.

In the production of this surface heating according to the prior art, the fabric layers 17 and 21 are each first connected in a Flammkaschierverfahren with the immediately adjacent foam layers 18 and 20 respectively.

In the Fig. 3a, 3b and 3c . 4a and 4b such as 5a and 5b further embodiments of heaters are shown in motor vehicles.

In the Fig. 3a a motor vehicle K is shown in a crack drawing, in which a sectional plane A through an inner lining 23 of a vehicle door 24 is shown schematically. The schematic sectional view of the inner lining 23 in the sectional plane A according to the in Fig. 3a is shown arrows as a second embodiment of a heatable article with a surface heating 2 in the Fig. 3b shown. This inner lining 23 contains as carrier 8, a carrier layer 24 to which the heating layer 7 is applied with electrically conductive plastic by means of adhesive 25. Since the visible surface of the inner lining 23 is formed by the heating layer 7 with electrically conductive plastic, the free visible side 26 of the heating layer 7 can be provided with electrically conductive plastic with a decor (not visible), such as an artificial leather-like appearance, to a pleasant appearance the inner lining 23 to achieve.

Alternatively to the embodiment described above, in a variant thereof, in the Fig. 3c is shown in a sectional view, the heating layer 7 with electrically conductive plastic by means of the adhesive 25 on the interior 26 of the motor vehicle K facing away from the carrier layer 24 may be attached. In such a case, either the support layer 24 itself on its visible side with a decor (not visible) to be provided, or a decor 27 (the sake of clarity, only partially indicated) may be applied to the visible side of the support layer 24.

The principle of the two embodiments just described can be transferred to the entire passenger compartment 26 of the motor vehicle K, in particular in so far as the corresponding parts are padded. For example, vehicle seats for realizing or supporting a seat heater, a mold headliner, hat rack, pillar garnish, consoles, a steering wheel, carpet material, air ducts, in particular, inside for preferentially preheating cold air and much more as heatable items having heaters including a heating layer 7 with electrically conductive plastic, be used to improve the indoor climate in a motor vehicle. This not only makes it possible to design the conventional heating systems smaller, but it can also be a faster and uniform distributed or targeted heating of the entire interior 26 of a motor vehicle K can be achieved. Other concrete embodiments of this are in the Fig. 4a and 4b and 5a and 5b clarified.

The Fig. 4a shows in a perspective view of a dashboard 28 and a console 29, the position of a sectional plane B, wherein the viewing direction to the sectional plane as shown in the Fig. 4b is illustrated by arrows. The Fig. 4b is the sectional view through the dashboard 28 in the sectional plane B, wherein also a part of an adjacent windshield 30 of the suitably equipped motor vehicle K is shown in section. The heating layer 7 with electrically conductive plastic forms the plastic skin, with which the instrument panel 28 is related and which forms the surface of the latter. By means of an adhesive 25, which is formed in the present fourth embodiment by a filling compound, such as foam, etc., the heating layer 7 is connected to electrically conductive plastic serving as a holder 31 carrier layer 24 as a carrier 8. The heating layer 7 with electrically conductive plastic forms a molded skin with incorporated conductive material. Alternatively, in this embodiment could be approximately analogous to the variant in the Fig. 3c is shown, the heating layer 7 with electrically conductive plastic nor with a decorative layer (not shown) to be coated.

In the Fig. 4b is shown as a further embodiment of an article with a surface heating 1, a windshield 30 in section partially. This windscreen 30 is provided in the region of its circumference with a black ceramic layer 32, which may be applied for example by screen printing. It is further provided that in the region of the ceramic layer 32, a heating layer 7 with electrically conductive plastic directly or by means of an adhesive 25, such as adhesive, is attached to the windshield 30.

By this configuration, e.g. a peripheral additional and / or separate heating of the windshield 30 to prevent fogging, fitting removal or de-icing can be realized. In addition, such a surface heating 1, in particular in the rest position of windshield wiper blades (not shown) may be provided to realize here an additional and / or separate heating of the windshield 30, so that damage to frozen wiper blades (not shown) upon actuation of the windshield wiper ( not shown) can be avoided.

If the heating layer 7 comprises electrically conductive plastic of transparent material, a transparent area of a pane, such as e.g. a windshield 30, are provided with a corresponding surface heating 1. As a result, it is likewise possible to remove or avoid misting up of a pane equipped in this way, and also to defrost icing. The heat conductors previously used, for example, in rear windows (not shown) could then be omitted or dimensioned smaller.

As a further variant for the interior heating of a motor vehicle K is in the Fig. 5a and 5b the design of carpet material 33 with a surface heating 1 illustrates. In this sixth embodiment, in the Fig. 5b is illustrated in a partial sectional view, the direction of the arrow on a sectional plane C in the figure of Fig. 5a can be seen, the construction of such a carpet material 33 is shown. In this case, the heating layer 7 is connected to electrically conductive plastic by means of the adhesive 25 with a lower carrier layer 24 as a carrier 8.

The bristles, loops or generally fibers / threads 34, which form the upper side of the carpet material 33, can either be attached to the carrier layer 24 and pass through the heating layer 7 with electrically conductive plastic, may be directly attached only to the layer of electrically conductive plastic, or may emanate from a separate layer (not shown), which is connected by means of adhesive 25 to the heating layer 7 with electrically conductive plastic. In the latter case, the carrier layer 24 may also be omitted and the carrier 8 may be formed by such a separate layer (not shown).

In the context of the present invention, it is also when the heating layer 7 is formed with electrically conductive plastic directly through the support layer 24, or if the heating layer 7 with electrically conductive plastic by means of bristles, loops, fibers or threads 34, which is the top of the carpet material 33 form, is attached to the carrier layer 24.

Furthermore, it is possible to attach the heating layer 7 with electrically conductive plastic using an adhesive 25 on the underside of the carrier layer 24, so that conventional carpet material 33 can continue to be manufactured in the usual way and subsequently provided with the surface heating 1. It is also possible to retrofit existing carpet material 33 accordingly with a surface heating 1.

As already mentioned, by connecting the heating layer 7 with the electrically conductive plastic material to a power source (not shown), it is possible to achieve a desired heating or heating effect on the corresponding heated objects. Since the electrical resistance of the heating layer 7 is constant, the heating temperature can be determined or regulated via the supplied electrical power. In this case, it is advantageously possible to use both direct current and alternating current, in particular without electrosmog being produced. Furthermore, since the heat generated in this way is exclusively radiant heat, a certain degree of temperature and heating comfort is created.

When using natural raw materials, e.g. Wood fiber, sisal, material from banana trees, coconut fibers, etc., often represent an odor in wet weather and bacterial infestation great problems. If, as in the embodiments described above, interior trim parts are designed to be heated, can in combination to the pure warming effect additionally avoiding Such odors and bacterial attack can be achieved.

Further concrete examples of heatable articles with a surface heating 1 according to the present invention are, for example, a diesel fuel tank, whereby a Verulzung of diesel fuel at low outdoor temperatures can be prevented by a minimum temperature can be maintained, an oil pan, by heating motor oil for better and more efficient operation of the engine can be preheated, a whole engine compartment, which allows a preheating of the engine, as well as, for example, a cargo space in both passenger cars and trucks. This surface heating 1 can be used with advantage in the vehicle interior and in the vehicle exterior.

However, the present invention is not limited to use in the field of motor vehicles. All of the aforementioned exemplary embodiments and variants as well as analogous applications can also be used, for example, in other vehicles in two-wheeled vehicles, in the railway sector, in ships and aircraft.

As already mentioned, numerous other fields of application of the present invention are possible, for example, in motorcycles and mopeds and the like. Benches and controls are equipped with corresponding surface heating. Further applications are, for example, in the household (coating of plastic wallpaper, wooden ceilings, wooden floors, carpets, tiles, sheaths of heating and water pipes, Underfloor heating), in clothing u. Ä. (Shoes, boots, ski boots, work clothes, protective clothing, gloves, electric blankets, thermal blankets, for example, in the hospital area, heat containers), in sports and leisure (artificial grass sports grounds, tent floors, sleep pads in the tent) and the military (including preheating in the vehicle for better start of the Motors in winter).

Only as preferred electrically conductive or electrically conductive feasible plastic materials are mentioned in particular aliphatic and aromatic polyurethanes.

With regard to the production of a surface heating according to the invention or of an article, it is therefore preferred if the layer is produced with or made of electrically conductive plastic in the spraying or dipping process or by roller application. A corresponding coating is preferably provided in a method of manufacturing a heater or an article therewith. In particular, the invention also makes it possible to adapt or select the coating method with regard to the geometry of the mold to be coated and / or the number of pieces to be produced.

In the exemplary and comparable embodiments discussed above, the layer thickness of the electrically conductive layer is preferably between about 0.05 mm and about 0.3 mm. When the electroconductive layer is also to function as a visible surface, it is preferable that the thickness be thicker. In particular, it is also within the scope of the present invention to adapt the layer thickness depending on the requirement or the requirement profile of the surface heating or the object or object (s), which can easily be found out by considerations or experiments. For example, a layer thickness of 1.2 mm is provided, if it is a surface layer with additional function, such as a vehicle interior trim.

As already stated, particularly preferred specifications for the plastic material of the heating layer 7 are that it contains or consists of polyurethane, preferably crosslinked and / or one-component polyurethane, which is in particular UV-resistant and hydrolysable or vapor-permeable.

As a particular specialty of the present invention, a variant is to be considered, in which at the same time for seat heating with the arrangement of the surface heating 1, a particular weight-dependent seat occupancy detection is realized. Such seat occupancy detections must nowadays be realized separately, for example, to perform an airbag deployment in the event of an accident only when sitting on a corresponding seat of an occupant. Due to the combined realization of the surface heating 1 according to the present invention with the simultaneous function of a seat occupancy recognition, which can also provide weight-dependent information to possibly control nature and severity of an airbag deployment accordingly, not only construction costs, but also volume and weight in or Saves on the vehicle, in places where it is not necessary for stability and safety of the vehicle.

The surface heating 1 contains in particular a striped heating layer 7 with electrically conductive plastic, such as in the Fig. 6 is illustrated schematically. Moreover, all the features according to the design of the Fig. 1a and 1b can be combined with the present embodiment and understood by any person skilled in the art, so that is omitted here to corresponding descriptions.

Although not shown separately in the drawing, but nevertheless an essential application of the present invention is a mattress with a surface heating according to the invention.

Such a designed mattress has over the prior art, in which a so-called electric blanket with metallic Widerstandsheizdrten the advantage that the reliability is at least substantially improved. It can not happen with a surface heating according to the present invention that a fire arises. In the event of damage to the heating layer, which may also be strip-shaped, no sparks occur, as with metallic conductors.

Also further forward, in particular in connection with the first embodiment has already been explained that the heating layer 7 is a film or a film. Preferably, it is a lacquer-like polyurethane layer or a polyurethane lacquer layer with the specified physical properties, in particular an enrichment with coal dust to achieve electrical conductivity. Furthermore, it is preferred if it is a one-component polyurethane material and / or an enrichment with coal dust for the electrical conductivity is provided.

A preferred thickness of the heating layer 7 is from about 0.3 mm to about 0.5 mm.

Instead of the spray application of the electrically conductive plastic material to the carrier, which has already been described in more detail above, a rolling method can also be used, for example. In this case, for example, liquid polyurethane is applied to a roller and discharged to a substrate, such as the carrier or an external base. The distance of the roller circumferential surface from the substrate determines the thickness of the heating layer. After solidification or curing of the polyurethane, in turn, a paint film having the desired properties is obtained, wherein molding operations on the film, including cutting, roll coating or after, can be carried out, as already explained above.

If, by a suitable method, the heating layer is optionally produced on the support, the heating layer may optionally be used alone or already together with the support with a support or e.g. a molding or a cover are connected by sewing, gluing, Velcro, etc., which has also been discussed earlier.

The surface heating can be operated with direct or alternating current, whereby the response is better when operating with direct current.

Further advantages of the surface heating according to the invention are in addition to the cost advantage over previous systems with metallic heating wires in the uniform heating behavior and in the lower power consumption compared to previous conventional seat heaters with metallic heating wires, as a corresponding series of experiments shows.

Compared to a market standard seat heating by Bauerhin (model S4300) with a surface heating according to the invention with a heating mat made of electrically conductive plastic. Seat and back of the seat were each separately controlled. The heating mat was hooked on top of headrest sleeves on top of the seat and attached to the edge by tape.

The measurements should provide information about the heating behavior and the current consumption of the two seat heaters. The aim of the experiment was specifically to find out the heating times with the associated power consumption for both types. For this purpose, a constant voltage of 12 V was applied to the terminals on both heaters. The recorded current is measured by a power meter integrated in the power supply. At intervals of 1 min, the temperature and the current are measured. The comparison between the two heaters is made using the recorded values at the seat. Heating mat made of conductive plastic Time in min Heating S4300 company Bauerhin temperature electricity temperature electricity in ° C in A in ° C in A 21.4 7.4 0 22.4 0.0 26.0 7.1 1 24.1 7.8 30.4 6.8 2 26.9 7.7 36.0 6.7 3 28.8 7.7 37.0 6.6 4 30.3 7.6 37.0 6.6 5 31.1 7.6 39.1 6.5 6 31.3 7.6 40.3 6.5 7 32.5 7.6 41.4 6.5 8th 33.0 7.6 42.1 6.5 9 34.0 7.6 42.6 6.5 10 34.4 7.9 43.1 6.5 11 34.7 7.6 43.7 6.5 12 35.0 7.7 44.4 6.5 13 35.4 8.0 44.7 6.5 14 35.8 8.0 45.1 6.5 15 35.6 7.6 46.0 6.4 25 36.0 7.6 48.1 6.6 50 36.1 7.7

The temperature measuring point was at the heating mat of the surface heating according to the invention with a heating layer with electrically conductive plastic approximately in the middle of the seat. In the example of the conventional construction with metallic heating wires, the temperature measuring point was about 0.5 cm next to a heating wire. The temperature measured on the heating wire itself was after 25 min at 50 ° C. This temperature is required to achieve a surface effect. This, however, in practice, considerable problems associated, for example, by the wire can anneal or ignite the seat cover due to high temperatures. With the inventive surface heating these problems are resolved.

Another not inconsiderable disadvantage is the u.U. occasionally high temperature at the position of the male genital area, which can lead to a disturbance of the fertility. The surface heating according to the invention already produces basically no overtemperatures, since they can actually deliver the heat over the entire surface, and can also be cut out at the appropriate location or made weaker.

Further tests have shown that the heating behavior of seat and back are about the same.

The superiority of the new surface heating according to the invention over the previous design with metallic conductor wires is quite clear from the test results.

The surface heating with the heating layer with electrically conductive plastic heats up faster and consumes less power than the conventional seat heating.

The invention thus provides a surface heating system which can dissipate heat over its entire area, which can be ensured even in the case of a design with a heating layer consisting of individual possibly spaced strips better than in the prior art, a pressure load of a base, such as a seat Foam body reversibly adapts and leads to no moisture or air congestion during use Although the present invention is basically not limited to the heating of upholstery items, however, the applications of the surface heating according to the invention as a seat or mattress heating for or in a / a seat, in particular Vehicle seat, a / a mattress particularly preferred and advantageous, so directed to a separate protection is justified. The flexibility of the heating layer is of particular importance.

Hereinafter, still another preferred embodiment of the invention with reference to in the Fig. 7 shown embodiment with reference to this drawing.

Analogous to Fig. 1 is shown in section a part of a surface heating 1, as the seat heating 4 as in the Fig. 2 can be used. This surface heating 1 contains as a carrier 8, a polyester or polyamide fabric with, for example, a mesh size of about 5 mm, ie, a mesh or grid, in which adjacent quasi-parallel strands of material have a distance of about 5 mm. The structure of the carrier 8 and its material is not limited to the above information, but can be selected by those skilled readily according to the particular mechanical requirements, ie other materials or material combinations and thicknesses of the material strands and other mesh sizes are application-specific selectable.

The carrier 8 is provided by spraying, dipping, rolling or otherwise with a layer of electrically conductive plastic according to the present invention, also as indicated in the other documents. This means that the strands of material of the polyester or polyamide fabric are completely surrounded or encased by the electrically conductive plastic which thus forms the heating layer 7.

As a further special feature in the polyester or polyamide fabric, ie in the carrier 8, for example, at a distance of 5 to 10 cm current-carrying silver or copper wires woven, which in analogy to the first embodiment according to the Fig. 1 the contact ends 9 and 10 of power supply wires 11 and 12 form. Since by spraying, dipping, rolling or otherwise applying (with) the layer of electrically conductive plastic according to the present invention, the silver or copper wires, ie the contact ends 9 and 10 are surrounded or coated with the electrically conductive plastic, is provided for optimum electrical contact in between. The distance of the silver or copper wires as contact ends 9 and 10 of the power supply wires 11 and 12 is not limited to the specified value range, but rather can be readily selected by those skilled in particular according to the particular mechanical and electrical requirements, ie other materials or material combinations and Thickness of the contact ends 9 and 10 and other distances can be selected depending on the application.

In the case where the surface heating 1 is a seat heater 4, in particular in a direction approximately 90 to the direction of travel of a vehicle (not shown), the contact ends 9 and 10 preferably extend in a non-limiting manner. In principle, however, the contact ends 9 and 10 in the form of the silver or copper wires can run in any longitudinal or transverse direction.

• 300 g Kautschuk, der bei der Herstellung als Granulat, im vorliegenden Fall als feinster Staub, verwendet wird,
• 300 g Tetrahydro-Furan,
• 165 g Graphit, und
• 300 g eines Polyurethans, wie beispielsweise und mit Vorzug 4715 Lupranol der Firma BASF.

A particularly preferred material composition for the heating layer 7, ie for the electrically conductive plastic is:

• 300 g of rubber, which is used in the production as granules, in the present case as the finest dust,
• 300 g of tetrahydro-furan,
• 165 g of graphite, and
• 300 g of a polyurethane, such as and with preference 4715 Lupranol BASF.

This gives a total of 1065 g. For other quantities, the shares are to be calculated accordingly.

• ca. 20-35 %, vorzugsweise ungefähr 25-30 %, besonders bevorzugt etwa 28 % eines Kautschuks oder insbesondere mechanisch und/oder elektrisch gleich oder ähnlich wirkenden Materials,
• ca. 20-35 %, vorzugsweise ungefähr 25-30 %, besonders bevorzugt etwa 28 % Tetrahydro-Furan oder eines insbesondere mechanisch und/oder elektrisch gleich oder ähnlich wirkenden Materials,
• ca. 5-25 %, vorzugsweise ungefähr 10-20 %, besonders bevorzugt etwa 15 % Graphit oder eines insbesondere mechanisch und/oder elektrisch gleich oder ähnlich wirkenden Materials, und
• ca. 20-35 %, vorzugsweise ungefähr 25-30 %, besonders bevorzugt etwa 28 % eines Polyurethans, wie beispielsweise und mit Vorzug 4715 Lupranol der Firma BASF, oder eines insbesondere mechanisch und/oder elektrisch gleich oder ähnlich wirkenden Materials.

Preferably proportions of the individual components of the material composition for the heating layer 7, ie for the electrically conductive plastic are:

• about 20-35%, preferably about 25-30%, more preferably about 28% of a rubber or especially mechanically and / or electrically equal or similar material,
• about 20-35%, preferably about 25-30%, more preferably about 28% tetrahydro-furan or a material which in particular acts mechanically and / or electrically the same or similar,
• about 5-25%, preferably about 10-20%, more preferably about 15% graphite or a particular mechanically and / or electrically the same or similar acting material, and
• about 20-35%, preferably about 25-30%, more preferably about 28% of a polyurethane, such as and preferably 4715 Lupranol BASF, or a particular mechanically and / or electrically the same or similar material.

Another embodiment of the invention will be explained below.

By measuring the change in the power consumption of the heating layer 7, a seat occupancy detection can be realized in a particularly simple and advantageous manner. This seat occupancy detection functions both to determine if anyone is sitting on the seat and, more specifically, to determine the weight of the occupant sitting on the seat. This aspect of the present invention is on the one hand particularly advantageous in connection with the surface heating, and on the other hand can also be used separately as sole seat occupancy recognition with a structure and features analogous to those disclosed for the surface heating in the entire existing documents, which seat occupancy recognition thus also on its own is worthy of protection and may possibly be part of separate patent applications and industrial property rights.

The present invention has been explained above with reference to exemplary embodiments, but to which the invention is based is not limited. All modifications, combinations, variations, and substitutions of the features discussed above and illustrated in the drawings are included within the scope of skill in the art of the present invention. The invention includes in particular all design options that are within the scope of the appended claims. In particular, the indicated uses of the heating devices according to the invention are disclosed and, if appropriate, regarded as worthy of protection.

Claims (31)

1. A surface heating device with a support and a heating layer, which includes electrically conductive plastic material, wherein the heating layer (7) is formed by a flexible film and the support (8) is flexible,
   characterized in that
   the material composition for the heating layer (7), this means for the electrically conductive plastic material, comprises:

   - ca. 20 - 35 % of a caoutchouc,

   - ca. 20 - 35 % tetra hydro-furan,

   - ca. 5 - 25 % graphite, and

   - ca. 20 - 35 % of a polyurethane.
2. A surface heating device according to claim 1, characterized in that the support (8) is a layer, in particular a fabric or a fleece, preferably a natural or synthetic fiber fleece.
3. A surface heating device according to claim 1 or 2, characterized in that the heating layer (7) includes polyurethane, one component polyurethane, linked one component polyurethane, a PU foam, UV resistant and/or hydrolysis capable or vapor permeable plastics material, and/or in that the electrically conductive plastic material of the heating layer includes graphite, preferably in powder form.
4. A surface heating device according to one of the preceding claims, characterized in that within the heating layer (7) or between the support (8) and the heating layer (7) contact ends (9, 10) of power supply wires (11, 12) are in contact with the heating layer.
5. A surface heating device according to claim 4, characterized in that the contact ends (9, 10) of the power supply wires (11, 12) are attached to the heating layer (7) through the heating layer itself.
6. A surface heating device according to claim 4, characterized in that the contact ends (9, 10) of the power supply wires (11, 12) are sewn or glued to the heating layer (7) and/or the support (8).
7. A surface heating device according to one of the preceding claims, characterized in that the heating layer (7) is formed directly on the support (8) through spraying, rolling or brushing.
8. A surface heating device according to one of claims 1 to 7, characterized in that the heating layer (7) is glued, sewn or welded to the support (8).
9. A surface heating device according to one of the preceding claims, characterized in that the support (8) is a formed part (6) made of an elastic material.
10. A surface heating device according to claim 9, characterized in that the formed part (6) is a seat cushion of a seating area part (3) or of a backrest (16), or a cushion of a seating or lying furniture, in particular a mattress.
11. A surface heating device according to one of the preceding claims, characterized in that a manually and/or electrically/electronically operable and/or automatic power control (13) is provided, which can be connected to a power source (1A) and to which power supply wires (11, 12) are connected, the contact ends (9, 10) of which are in contact with the heating layer (7).
12. A surface heating device according to one of the preceding claims, characterized in that the support (8) is formed by a fabric, which is preferably a polyester- or polyamide fabric, and/or has a mesh size of approximately 5 mm.
13. A surface heating device according to claim 12, characterized in that contact ends (9, 10) of power supply wires (11, 12) are woven into the fabric and preferably have a distance of 5 - 10 cm and/or are made from silver or copper wires.
14. A surface heating device according to claim 12 or 13, characterized in that the support (8) is provided with the heating layer (7), this means with a layer of electrically conductive plastics, through spraying, dipping, rolling or otherwise so that preferably the support (8) and/or the contact ends (9, 10) are completely enclosed or en cased by the electrically conductive plastic material.
15. A heatable object, characterized in that a surface heating device (1) according to one of the preceding claims is comprised.
16. A heatable object according to claim 15, characterized in that the object is a seating area part (3) or a backrest (16) or a cushion of a seating or lying furniture, in particular a mattress, and in that preferably the heating layer is anatomically adapted to the thigh-buttock-portions and/or back portions of a user.
17. A heatable object according to claim 16, characterized in that the heating layer (7) is anatomically formed in the plane of the seating area part (3) or of the backrest (16) or of the cushion of a seating or lying furniture, in particular of a mattress, in that it is only present or electrically conductive according to anatomic specificatioins.
18. A heatable object according to claim 16 or 17, characterized in that for anatomically adapted heat delivery the heating layer (7) comprises a corresponding thickness profile.
19. A heatable object according to claim 15, characterized in that the object is a padded lining (23), in particular of a vehicle (K).
20. A heatable object according to claim 19, characterized in that the surface heating device (1) of the object is adapted to a heat supply varying over its area.
21. A heatable object according to one of claims 15 or 20, characterized in that the heating layer (7) is profiled in its plane expansion and/or in its thickness for heat supply varying over its area.
22. A method for producing a surface heating device according to one of claims 1 to 14, wherein a heating layer with electrically conductive plastic material is connected to a support, characterized in that the heating layer (7) is formed by firstly applying an electrically conductive, in particular foaming or foam-plastics material onto the support (8), and then curing the plastics material on the support (8).
23. A method according to claim 22, characterized in that before applying the electrically conductive, in particular foaming or foam-plastics material onto the support (8), firstly contact ends (9, 10) of power supply wires (11, 12) are disposed on this side of the support (8), onto which the plastics material is then applied.
24. A method for producing a surface heating device according to one of claims 1 to 14, wherein a heating layer with electrically conductive plastic material is connected to a support, characterized in that the heating layer (7) is made from an electrically conductive, in particular foaming or foam-plastics material, and then disposed on the support (8).
25. A method according to claim 24, characterized in that the heating layer (7) after being placed on the support (8) is connected to the support (8) slip proof.
26. A method according to claim 25, characterized in that the heating layer (7) is sewn, glued or welded to the support (8).
27. A method according to one of claims 22 to 26, characterized in that electrically conductive polyurethane is used as plastics material.
28. A method according to one of claims 22 to 27, characterized in that contact ends (9, 10) of power supply wires (11, 12) are mounted at the heating layer (7) and/or at the support (8), such that in the composite of support (8) and heating layer (7) they are in contact with the latter.
29. A method according to claim 28, characterized in that the contact ends (9, 10) of power supply wires (11, 12) are sewn or glued to the heating layer (7) and/or the support (8).
30. A method according to one of claims 22 to 29, characterized in that the heating layer (7) is profiled in its area surface shape and/or thickness during or after its production.
31. A method for producing a surface heating device according to one of claims 1 to 14, wherein a heating layer with electrically conductive plastic material is connected to a support, characterized in that a fabric is produced as a support (8), in that contact ends (9 and 10) of power supply wires (11 or 12) are simultaneously or subsequently woven into said fabric, and in that then a heating layer is applied to the support (8) and to the contact ends (9 and 10).

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