DE102009025454A1 - Infeed strip or strip for supplying a planar heating element with electrical energy - Google Patents

Abstract

In order to provide a feed belt or a feed bar for supplying a flat heating element with electrical energy, which (s) offers a simple, flexible and versatile way for the connection of the planar heating element to the electrical energy supply, it is proposed that the feed belt or the feed bar in Is formed essentially of an electrically insulating material and comprises at least a first and a second electrical conductor, which extend from one another in the longitudinal direction of the band or strip and are surrounded by the insulating material; a plurality of first and second contact portions are arranged at predetermined intervals along the band or strip, in which the first and second electrical conductors are accessible from one side of the band or strip; and wherein the first contact portions are offset from the second contact portions in the longitudinal direction.

Description

The The invention relates to a novel feed belt or a novel Infeed strip for supplying a planar heating element with electrical energy.

Further The invention relates to a flat heating element, which includes such a feed belt or a feed bar, and various uses of the planar heating element, in particular in heated seats, floor or wall coverings and heatable Containers.

For the heating of motor vehicle seats, upholstered furniture, mattresses etc., various electric heating systems are known. For some time, especially flat heating elements have come here for use (so-called surface heating), opposite the use of individual heating rods or heating wires have a number of advantages. On the one hand, such Heating elements to flexible sheet materials, with relative little effort to the size required in each case and shape can be adjusted so that the heating elements are very versatile and installed with little effort can be. Above all, however, the flat heating elements a very evenly over the corresponding area distributed heat dissipation. This also increases operational safety, since local overheating, as they occur in particular when using heating rods, can be avoided more easily.

The surface heaters described above typically include a carrier coated with an electrically conductive material. For example, the carrier can be a grid, braid or fabric of glass fibers (or else polyester or polyamide filaments), which is coated with a graphite particle-containing polyurethane binder, ie a conductive plastic material, as described in the European patent EP 1 554 911 B1 is described.

at Such a flat heating element is usually advantageous if this comprises a plurality of power supply lines, the Divide heating element into several surface sections. By a parallel connection of these power supply lines, a higher Have conductivity as the electrically conductive plastic coating, is the electrical resistance of the flat heating element essentially regardless of its size. In addition, this is the reliability of the heating element increased, since in case of damage or severing of Carrier and / or the coating only the corresponding Area section is affected.

The Power supply lines are z. B. copper wires to each other in parallel at regular intervals in the carrier of the flat heating element (eg Grids with a mesh size of approx. 5 mm) are incorporated, and alternately a positive and negative voltage is created. The connection of the power supply lines to the power supply However, it is relatively complex, because each Power supply individually z. B. connected by soldering must become. This is for larger heating elements very time-consuming and labor-intensive; required wiring for every installation situation of the Heating element according to the spatial conditions adapted and the cables are laid accordingly.

Of the Invention is based on the object, a simple, flexible and versatile option for connection a flat heating element to the electrical power supply provide.

These The object is achieved by a feed belt or a feed bar of the aforementioned Art, wherein the band or bar essentially from an electric insulating material is formed and at least a first and includes a second electrical conductor extending from each other spaced in the longitudinal direction of the band or the strip extend and are surrounded by the insulating material; in which at predetermined intervals along the belt or bar each a plurality of first and second contact portions are arranged, in which the first and second electrical conductors accessible from one side of the band or bar; and wherein the first contact portions opposite to the second contact portions are offset in the longitudinal direction.

The Inventive feed belt or inventive Feed bar can be equipped with a flat heating element comprises a plurality of power supply lines to be connected in such a way that the individual power supply lines alternately with the first electrical conductor or with the second electrical conductor stay in contact. By applying a positive voltage to the first electrical conductor and a negative voltage to the second electrical conductor (or vice versa) then becomes the entire surface Heating element supplied with electrical energy.

The distinction between a feed belt and a feed rail in the context of the present invention refers to the flexibility of the electrically insulating material of which the tape or the strip is formed. Of course, the invention also includes such bands or strips, in which the electrically insulating material has an average degree of flexibility and therefore referred to correctly with both terms could be (eg hard rubber). For the sake of simplicity, the term feed band is used below for all embodiments of the invention, without this being understood as a restriction to a specific material or a certain flexibility, unless explicitly stated otherwise.

The two sides of the feed belt according to the invention are defined in terms of the level in which the first and the second electrical conductor in the longitudinal direction of the band extend. According to the electrical Conductor in the first and second contact portions from one side of the Bandes accessible, d. H. this page forms the contact surface between the feed belt and a flat heating element. This does not exclude that too on the opposite Side of the feed belt contact sections are arranged in the However, this is usually not necessary or desirable.

conveniently, are the distances between adjacent first contact sections and between adjacent second contact portions respectively in the Essentially the same. Furthermore, the second contact sections preferably in each case in the middle between two adjacent first Contact sections arranged. In this way follow each other alternately first and second contact sections in regular Distances so that the inventive Feed belt in combination with a flat heating element with a corresponding regular sequence can be used by power supply lines.

Corresponding should also be the distances between the contact sections to the corresponding distances in the flat Be adapted heating element, these depending on the type and dimensions of the heating element can vary. Typically lie the distances between adjacent first contact sections and between adjacent second contact portions in the area from about 5 to about 20 cm, especially in the range of about 8 to about 15 cm.

The Length of the contact sections, d. H. whose extension in Longitudinal direction of the feed belt is preferably about 3 to about 15 mm, more preferably about 8 to about 12 mm. The contact sections should have a sufficient length, so even at slightly irregular intervals between the power supply lines of the flat heating element in any case, an electrically conductive contact between the power supply line and the contact portion is ensured. To short contact sections moreover complicate the correct positioning of the Feed belt on the heating element. The contact sections should On the other hand, it should not be much longer than this The described points of view is necessary, otherwise under To stand also areas of the heating element between the power supply lines directly come into contact with the contact sections, resulting in a higher Amperage and overheating of the heating element can lead in this area.

The electrical conductor in the feed belt according to the invention are preferably formed of a metallic material which has a good electrical conductivity. Especially preferred are electrical conductors made of copper or silver.

in the Regarding your structure, the first and the second electrical conductors, in particular as a metal profile, as a metal strip, be designed as metal mesh or as a stranded wire. Metal bands, - Braids and strands are characterized by a high degree of flexibility and are therefore with particular advantage in a feed belt with a likewise flexible electrically insulating material used. The use of strands (eg copper strands) is special in this respect advantageous than these are deformable to some extent and thus when contacting the power supply lines of the flat Heating element as large a contact surface can be achieved. In the case of a feed bar from a relative stiff electrically insulating material may alternatively also rather inflexible metal profile for the electrical conductors be used.

The But electrical conductors can also be conductive Be formed coating, in particular by a coating the electrically insulating material of the feed belt. Such conductive coating preferably comprises a printed, evaporated or sputtered metal. Furthermore you can the electrical conductors also conductive staple yarns include.

at a preferred embodiment of the invention the electrically insulating material is a textile material. Textile Materials are typically very flexible and can bent without the risk of damage almost arbitrarily and to be kinked. In this case, it is in the inventive Einspeisband a band in the true sense of the word. A surface heating, which is combined with such a flexible feed belt, loses nothing of its own flexibility a, so this embodiment of the invention in particular when using the heating element in upholstery and seat heaters advantageous is where usually an adaptation to curved Structures is required.

Another advantage of textile materials is that the feed belt in a simple manner by sewing on the flat Heizele can be attached. Alternatively or additionally, however, the feed belt can also be glued to the heating element or connected by means of staples.

The textile material is preferably a woven, knitted or knitted Ribbon or a fleece band. Such textile bands can be made in bulk to the meter, the user then depending on the dimension of the flat heating element a corresponding piece cuts. A woven one Tape is particularly preferred because it knitted against or knitted ribbons have a higher tensile strength or dimensional stability.

there it is preferred if the electrical conductors in each case in Lengthwise extending, tubular Areas of woven, knitted or knitted ribbon or Fleece band are included. Such tubular areas are conveniently web, knitting or knitting technology in the tape incorporated. In the case of a woven band run while the warp threads in the longitudinal direction and the weft threads in the direction of the width of the feed belt, wherein in the tubular areas two layers of warp threads are present, between which the electrical conductor is arranged, and each half the weft threads through one or the other position of Warp threads runs. The electrical conductors, in this case z. B. copper strands, can in this way umwebt werden, d. H. they are already in the production of the woven tape integrated into the tubular areas. Prefers The electrical conductors are umwebt as closely as possible, so they frictionally in the tubular areas are held and only with a certain effort in the longitudinal direction can be moved.

The Feed belt preferably also has two opposite Edge areas on, between which the tubular areas are arranged for the electrical conductors. These border areas can be used in particular to the inventive Sew supply strap with a flat heating element. In the border areas and possibly in a central area between the tubular areas for the first and for the second electrical conductor lies in usually a simple woven band before (or a knitted or knitted ribbon or a nonwoven ribbon).

The above-described feed belt made of a textile material can be very simple and flexible to power a flat Heating element used: The feed belt is doing on the required length is cut and perpendicular to the power supply lines of the heating element with the appropriate positioning the first and second contact portions sewn on this. The feed belt can be both along the edge and within of the heating element (eg centrally).

According to one particular embodiment of the feed belt is one the edge regions of the woven, knitted or knitted ribbon or the nonwoven tape widened so that when folding the tape along a longitudinal centerline the widened edge area over the tubular Areas for the electrical conductors and over the opposite edge area comes to rest. One Such feed belt is along the edge of a flat Heater mounted, with the edge of the heating element along the center line of the feed belt comes to lie and the widened Edge area is then folded over. The two over each other lying areas of the feed belt can then with the sewn between the heating element. These Embodiment of the feed belt according to the invention offers the advantage of being sewed through the two-ply the feed belt, the power supply lines of the heating element and the Kon contact sections of the electrical conductor of the feed belt with a greater force pressed together be made, whereby a better electrical contact can be made can. Furthermore, the contact portions are widened by the Covered edge area and thus against unwanted touch protected, which in particular with heating elements with a large-mesh structure is significant. Also the sewing a large mesh heating element with a simple feed belt can be problematic, by a double-layered structure is also this Problem avoided.

The distributed along the feed belt contact portions may be formed by recesses of the textile material on one side of the belt. Such recesses can z. B. by cutting or punching of the textile material in the corresponding sections of the tubular areas are obtained. However, it is preferred if the contact sections are formed by the electrical conductors passing through the textile material. This is to be understood as a type of floatation of the electrical conductor, ie in the case of a woven band, the electrical conductor emerges from the tubular region at one end of the contact section between two weft threads, displacing the warp threads to the side, and occurs at the other end of the contact section again in the same way in the tubular area. Such flooding of the electrical conductors has the advantage that, in contrast to recesses, no threads of the textile material have to be severed and thus there is no danger that the textile material fray or tear.

The textile material of the feed belt according to the invention can be made of synthetic and / or natural fibers be particular fibers with a high tensile strength are favorable. Preference is given to polyesters, polyamides or Mixtures thereof.

Prefers the textile material is flame-retardant. This contributes to the reliability of the heating element, as overheating never completely excluded in such systems can be.

Cheap is also a use of glass fibers for the textile Material that has both high strength and temperature resistance exhibit.

According to one further preferred embodiment of the invention the feed belt further comprises third and fourth electrical conductors, which are spaced apart in the longitudinal direction of the band extend and are surrounded by the insulating material; in which at predetermined intervals along the band in each case a plurality of third and fourth contact portions are arranged, in which the third and fourth electrical conductors from one side of the band is accessible, such that when folding or bending of the Bandes along a longitudinal centerline in each case a third contact section on a second contact section and a fourth contact portion on a first contact portion to come to rest.

These Embodiment of the feed belt is along the edge a flat heating element and arranged around the edge folded or kinked, essentially in the way this continues above for a feed belt of a textile material with a widened border area has been described. By the presence including a third and a fourth electrical conductor their corresponding contact portions mirror image of the second or first electrical conductor are formed, is each power supply line the flat heating element with two contact sections in electrically conductive contact. The power supply lines are included in particular between these two contact sections, the z. B. squeezed by sewing the feed belt be fixed, so that a better and / or more reliable electrically conductive contact can be achieved. During operation the flat heating element become the first and the fourth electrical conductor of the feed belt with the positive pole and the second and third electrical conductors with the negative pole of the electrical Energy source connected (or vice versa).

Provided it is in the feed belt according to the invention with four electrical conductors around a feeding belt made of a textile Material acts, apply to the preferred embodiment the tubular areas, for education the contact portions, etc. with respect to the third and fourth electric Head also the above statements. additionally arise here the same advantages when sewing the folded in feed belt as in the case of the feed belt with only two electrical conductors and a widened border area.

Independently of whether the feed belt according to the invention two or four electrical conductors may additionally one or more signal lines may be provided, which are also extend in the longitudinal direction of the tape. In such Signal lines are also electrical conductors, but not the power supply of the flat heating element serve but the transmission of signals from the heating element to an evaluation and / or control device. The signal lines therefore, can usually have a higher resistance (ie, for example, a smaller cross-section) than the first and the second electrical conductor. In the transmitted from the signal line Signals can be z. B. to the current electrical resistance of the heating element, from which the current temperature is determined can be, or to a signal of a special in the heating element integrated sensor, such. As a seat occupancy sensor in the case a seat heater for motor vehicles.

A further preferred embodiment of the invention relates a feed bar, in which the electrically insulating material comprises a plastic material. Compared to a feed belt from a textile material is a feed strip in the sense of present invention relatively dimensionally stable and has a clear less flexibility, with some applications of surface heating must not be a disadvantage. The Plastic material from which the feed bar is formed comprises preferably a thermoplastic or an elastomer. While basically a large number of representatives of these substance categories can be used are high-performance plastics such as As polyphenylene sulfide or polyether ketone due to their high Temperature resistance preferred.

Cheap it is when the feed bar is covered by a sheathing of electrical Ladder with the plastic material by means of an injection molding or Extrusion process is made. For example, you can two parallel electrical conductors in an extrusion process be overmoulded with the plastic material. As electrical conductors can here z. B. strands or sturdy metal profiles be used.

The Contact sections are preferred by recesses of the plastic material formed on one side of the feed bar. Such recesses can produced after completion of an injection molding or extrusion process by passing the plastic material along the contact sections Cutting, grinding, milling or the like away becomes. For this it is advantageous if the plastic material on the side of the bar where the contact sections are provided are just a relatively thin layer over the forming electrical conductors. If the plastic material on this Side at regular intervals with predetermined breaking points is provided, what z. B. possible in an injection molding process is, so can the contact sections by breaking out of the Plastic material can be obtained. Very cheap It is with this variant, if the distances between the predetermined breaking points are much smaller than between the intended first or second contact sections, since this allows the user by appropriate breaking the distances between the Contact sections to the distances between the power supply lines adapt in the respective planar heating element.

at a preferred embodiment of the invention Feed bar includes this one lower area and an upper one Area that has a flexible area in the longitudinal direction connected to each other, wherein the first and the second electrical Ladder are arranged in the lower area, and wherein the upper Area is pivoted so that it is in a closed position the bar over the contact sections of the first and the second electrical conductor comes to rest. Such a feed bar is along an edge of a flat heating element with this connected by the edge of the heating element between the bottom and is trapped in the upper area of the feed bar. Of the flexible area of opening and closing the bar in the form of a pivoting movement is possible preferably obtained by the fact that the plastic material in this Area is sufficiently thin.

In order to the flat heating element between the lower and the upper Area of the bar is fixed and an electrically conductive contact between the power supply lines and the contact sections ensured is, the feed bar can with additional closure elements such as B. brackets are fixed in the closed position. However, it is preferred if the feed bar itself one or more Includes closure elements by means of which they are in the closed position can be fixed. As closure elements may be at the bottom and / or upper portion of the bar each locking elements arranged be in corresponding recesses in each other Intervene area, z. B. in the form of a snap closure. The Closure elements are preferably each in the vicinity of the contact portions of the first and second electrical conductors arranged to be particularly in these areas the best possible non-positive To allow fixation of the planar heating element.

at a particularly advantageous embodiment of the feed bar are in the upper area a third and a fourth electric Head arranged. In the closed position of such a feed bar the power supply lines of the heating element are each between two Contact portions of the first and fourth electrical conductors or the second and the third electrical conductor fixed as this already above for the invention Feed belt in general and in particular for a feed belt was explained from a textile material. the same Benefits can also be with four electrical conductors a feed rail made of a plastic material can be realized. The contact portions of the third and fourth electrical conductors can be formed in the same way as in the first and second electrical conductors.

The The present invention further relates to a planar heating element, comprising a plurality of substantially parallel arranged Power supply lines and a feed belt (or a feed strip) of the type described above, wherein each power supply with at least one contact portion of the first or the second electrical Head of the feed belt is in electrically conductive contact. The type of connection between the flat heating element and the feed belt has already been described in detail above. In particular, the feed belt can be sewn to the heating element or be glued or fixed by means of fasteners.

The Heating element according to the invention can with very little Expense to be installed and connected, as only one end the first (and possibly the fourth) with electrical conductor the plus pole and one end of the second (and possibly the third) electrical conductor connected to the negative pole of the power source must be (or vice versa). This is due to the power supply lines of the heating element alternately a positive and negative Voltage, resulting in a corresponding current flow perpendicular to the power supply lines in the intermediate surface sections of the heating element leads.

The feed belt is preferably arranged substantially perpendicular to the power supply lines. Here, the distance between a first contact portion and an adjacent second contact area corresponds to the distance between two power supply lines of the heating element. Depending on the off guide rail of the feed belt is this arranged either along the edge or within the surface of the heating element, as described above.

The flat heating element itself, d. H. the surface heating, can be constructed in different ways and from different materials be. Typically, the heating element includes one with an electrical conductive material coated mesh, braid, fabric or the like, into which the power supply lines in regular Intervals are incorporated. For example, as a heating element Grid made of glass fibers are used, which with a dispersion coated by graphite particles in a polyurethane binder is. The power supply lines include in particular copper or silver wires or strands, which are also provided with the coating. The coating of the electrically conductive material can z. B. be applied by means of a dipping process on the grid, wherein the coating preferably has a thickness of about 0.3 mm to about 0.5 mm.

In In some cases it may be preferable if the power supply lines on an edge of the heating element, on which the feed belt is arranged is, survive. This can be avoided in addition to the power supply lines and surrounding areas of the heating element immediately are in contact with the contact sections of the electrical conductors, causing it in the area of the edge to increased current flow in the longitudinal direction of the feed belt and thus to a stronger warming can occur. Alternatively or In addition, this problem can also be countered by this be that the length of the contact sections allows is chosen small, as already explained above.

The Heating element according to the invention can be very diverse be used. The subject of the present invention is in In this context, the use of a planar Heating element of the type described above for heating Upholstered furniture, motor vehicle seats, interior linings of motor vehicles, mattresses, seat and couch pads or electric blankets. The heating element can be easily interposed in such applications two pads or the like inserted and in the above-described Be connected to the power source. Particularly preferred in this context, flexible feed belts that the advantageous flexibility and adaptability of the heating element does not affect or only to a small extent.

Of Furthermore, the invention relates to a modular element for a floor or wall covering of a plastic material, comprising a flat heating element of the above-described Kind, which is embedded in the plastic material. in this connection these are in particular plate-shaped elements, wherein the planar heating element as close as possible below the surface on one side of the modular element is arranged so that the majority of the heat generated just over this one side of the modular element in shape is delivered by convection and / or thermal radiation.

The Plastic material from which the modular elements are formed, preferably comprises a foamed or expanded Plastic. By such a material, in particular the weight of the modular element are significantly reduced, and on the other hand will provide good thermal insulation in the direction of the heating element reached away from the modular element. A special preferred material is expanded polypropylene (EPP), which in addition to the advantages mentioned above also a sufficient mechanical strength, in order for a soil or wallcovering to be used.

Prefers The modular element comprises connecting elements which form an and / or non-positive connection of multiple modular Enable elements. The fasteners can in the form of tongue and groove systems, click systems or the like be formed as they are known in the art are. By connecting a corresponding number of modular elements can in this way a floor or wall covering the desired Size obtained with which a room is heated can be. Due to the compact and simple construction is suitable this system of modular elements in particular for Facilities that are only needed temporarily and then dismantled again, such as B. exhibition stands.

Conveniently, the feed belt is disposed in the modular element such that when connecting a plurality of modular elements, the electrical conductors in adjacent modular elements are each in electrically conductive contact. Thus, in a number of modular elements, the first and second electrical conductors in each of the elements are interconnected so that only the electrical conductors of the first modular element in the series must be connected to the electrical energy source. To enable this type of connection, it is important that the predetermined position of the feed belt within the modular element is maintained as accurately as possible, ie in particular the position of the ends of the feed belt at the opposite ends of the modular element. For this reason, it is advantageous here to use a dimensionally stable feed strip instead of a flexible feed strip, since a flexibility of the planar heating element, which is firmly embedded in the plastic material, anyway not required.

Especially It is favorable when the electrical conductors are at their opposite Ends each with each other corresponding electrical connection elements exhibit. By such connection elements a possible good and safe electrical contact when connecting the modular elements be enabled. The corresponding electrical Connection elements can in particular plug on a End of the electrical conductors and sockets at the opposite end include, which interlock when connecting the modular elements. Depending on the type of fasteners connecting the modular Enabling elements are the electrical connection elements designed so that the meshing in the longitudinal direction the feed belt and / or can be done transversely thereto.

The Finally, the invention also relates to a heatable container of a plastic material, comprising a flat heating element of the type described above embedded in the plastic material is. Such a container is particularly suitable for the transport of food.

When Plastic material for the heated container are preferably foamed or expanded plastics used that already above related to the modular elements for floor or wall coverings, in particular expanded polypropylene (EPP). In addition, the container can have an outer cover, as additional protection and / or around the outside to make the container visually attractive.

Of the Container preferably has a bottom and at least one extending transversely from the ground wall, wherein the flat Heating element both in the ground and in the at least one Wall is embedded. This allows the interior of the container be heated evenly.

Within of the floor and the at least one wall is the areal Heating element preferably as close to the interior of the Container arranged, d. H. as close as possible the interior surface facing the plastic material, so the majority of the heat generated to the interior is discharged and the plastic material to the outside isolating effect.

Of the heated container can z. B. cylindrical be with a round bottom and a cylindrical one Wall. Particularly practical, however, is a cuboid Container with a rectangular bottom and four to the bottom vertical, in pairs parallel walls. In this case can a single planar heating element, which is approximately the shape of a cross, in the ground and the four walls to be embedded in the container. To supply this Heating element with electrical energy only one feed belt is required, which is conveniently by two opposite Walls and the bottom of the container extends.

at a preferred embodiment of the container includes this electrical connection elements, each with a electrical conductors are connected in the feed belt. With help This connection elements, the heating element by an external Power source to be powered, for example, over a socket in a motor vehicle.

According to one Another advantageous embodiment comprises the heatable Container an accumulator. In this way, the container independent of at least for a certain period of time an external power source to be heated. Very cheap it is when the container includes a lid in the the accumulator is integrated. In the lid and in the edge area of a Wall of the container can be corresponding be arranged electrical connection elements which are connected to the accumulator or are connected to the electrical conductors of the feed belt. When placing the lid on the container then come the corresponding connection elements engage each other and the heating element is powered by the accumulator. Opposite an arrangement of the accumulator in the ground or in a wall of the container has this embodiment the advantage that when loading and unloading the container the Weight of the accumulator is eliminated, causing the handling the container is facilitated.

Especially it is also favorable if the container different Connection elements z. B. at the opposite ends of the feed belt, on the one hand for connection of the accumulator in the lid and on the other hand for connection to an external power source serve.

Of the inventive container can due to its simple structure made relatively inexpensive and offers a convenient way to dine relatively to keep evenly warm, z. During transport with a motor vehicle. Alternatively, such Container due to the good insulating effect of the plastic material however also be used as a cooling container, in that instead of operating the heating element z. B. a cold pack is arranged in the interior of the container.

These and other advantages of the present invention will become apparent from the subsequent embodiments with reference to the drawing explained in more detail. They show in detail:

1 a first embodiment of a feed belt according to the invention;

2 a second embodiment of a feed belt according to the invention;

3 : the connection of the feed belt according to the 2 with a flat heating element;

4 : an embodiment of a planar heating element according to the invention;

5 : an embodiment of a heatable container according to the invention; and

6 a flat heating element for the container according to 5 ,

The 1 shows a portion of a first embodiment of a feed belt according to the invention, which as a whole with 10 is designated. The feed belt 10 is made of a textile material in the form of a woven band 12 formed, the z. B. made of polyester or polyamide fibers. The warp threads (K) of the woven ribbon 12 extend in the longitudinal direction and the weft threads (S) perpendicular thereto along the width of the feed belt 10 , Alternatively, a knitted or knitted ribbon or ribbon could be used.

The feed belt 10 includes a first electrical conductor 14 and a second electrical conductor 16 extending in the longitudinal direction of the feed belt 10 extend and in tubular areas 18 respectively. 20 of the woven ribbon 12 are included. The tubular areas 18 and 20 are weaving in the woven band 12 incorporated, wherein in these areas each half of the weft threads below or above the electrical conductor 14 and 16 (referring to the drawing plane). The feed belt 10 can be by interweaving the electrical conductors 14 and 16 be prepared, the electrical conductors 14 and 16 in the tubular areas 18 respectively. 20 be held by adhesion. The electrical conductors 14 and 16 are in this case copper strands, alternatively z. B. also metal bands are used.

Along the feed belt 10 are periodic first contact sections 22 and second contact portions 24 arranged in which the first electrical conductor 14 or the second electrical conductor 16 from one side of the feed belt 10 is accessible, ie from the side, in the 10 is shown in plan view. The second contact sections 24 are each in the middle between two first contact sections 22 arranged. The distance between two adjacent first contact sections 22 is dependent on the type of flat heating element for which the feed belt 10 should be used. In a typical example of a feed belt 10 this distance is in the range of 10 cm, with the length of the contact sections 22 and 24 about 1 cm and the textile tape 12 is about 2 cm wide.

The contact sections 22 and 24 are due to a floating of the electrical conductor 14 respectively. 16 formed, ie the electrical conductor 14 respectively. 16 passes through the fabric of the textile tape 12 between two weft threads, the warp threads of the tubular portion 18 respectively. 20 around the electrical conductor 14 respectively. 16 walk around. In this way, the contact sections 22 and 24 be formed without damage to the fabric, so there is no danger that the woven tape 12 fray or tear out.

The feed belt 10 can be used to supply a flat heating element with electrical energy, wherein the feed belt 10 is sewn onto this perpendicular to the power supply lines of the heating element, so that the power supply lines in each case alternately with a first contact portion 22 and a second contact portion 24 be in electrically conductive contact. Sewing the feed belt 10 with the heating element takes place along the edge regions 26 of the woven ribbon 12 and optionally along the middle area 28 between the two tubular areas 18 and 20 ,

A second embodiment of a feed belt according to the invention is partially in the 2 represented and there as a whole with 30 designated. The feed belt 30 includes as the first embodiment of 1 a woven ribbon 12 and two electrical conductors 14 and 16 that are in tubular areas 18 respectively. 20 of the woven ribbon 12 are recorded with first contact sections 22 or second contact sections 24 , The feed belt 30 is about twice as wide as the feed belt 10 and additionally includes a third electrical conductor 32 and a fourth electrical conductor 34 that are in tubular areas 36 respectively. 38 of the woven ribbon 12 are included. Along the third electrical conductor 32 are third contact sections 40 in each case at the level of the second contact sections 24 , and along the fourth electrical conductor 34 are fourth contact sections 42 in each case at the height of the first contact sections 22 arranged. The feed belt 30 is thus mirror-symmetrical to a longitudinal centerline 44 educated.

To supply a heating element with electrical energy is the feed belt 30 folded around a running perpendicular to the power supply line edge of the heating element and sewn thereto. In this way, each power supply line between a first contact section 22 and a fourth contact portion 42 or between a second contact section 24 and a third contact section 40 fixed. At one end of the feed belt 30 then becomes the first electrical conductor 14 and the fourth electrical conductor 34 connected to the positive pole of an electrical energy source and the second electrical conductor 16 and the third electrical conductor 32 to the negative pole (or vice versa).

In the 3 is shown as a flat heating element 46 on the (not yet folded) feed belt 30 is positioned. The heating element 46 is a so-called surface heating and includes a grid 48 made of glass fibers with a mesh size of about 5 mm, in the at regular intervals of about 5 cm parallel to each other power supply lines 50 are incorporated in the form of copper wires or strands. The power supply lines 50 divide the planar heating element 46 in several surface sections 52 ,

The fiberglass grid 48 including the power supply lines 50 is coated with an electrically conductive material. This coating comprises in particular a polyurethane binder with dispersed therein graphite particles, as z. B. in the EP 1 554 911 B1 is described. Due to this structure is the flat heating element 46 very flexible and can z. B. when used in upholstered furniture or motor vehicle seats are adapted to the respective predetermined shape.

Like in the 3 is shown, one to the power supply lines 50 vertical edge of the heating element 46 to the middle line 44 of the feed belt 30 created, with the feed belt 30 longitudinally positioned so that every other power supply line 50 with a third contact section 40 is in electrically conductive contact and the other power supply lines 50 each with a fourth contact section 42 , When folding the feed belt 30 along the midline 44 then comes in each case a first contact section 22 over a fourth contact section 42 and a second contact section 24 over a third contact section 40 to lie. Subsequently, the folded feed belt 30 with the flat heating element 46 sutured.

When connecting the feed belt 30 to a power source in the manner described above is to the power supply lines 50 alternately applied a positive or negative voltage. This leads to a flow of current in the individual surface sections 52 perpendicular to the power supply lines 50 , wherein this current flow in two adjacent surface sections 52 each has an opposite direction.

The 4 shows a perspective view of a flat heating element according to the invention 46 on which a feed belt 30 is arranged in the manner described above. For clarity, the grid is 48 not shown, but only the power supply lines 50 and the intermediate surface sections 52 , The folded in feed belt 30 is through seams 54 on the heating element 46 attached, with the seams 54 in the longitudinal direction of the feed belt 30 next to or between the electrical conductors 14 . 16 . 32 and 34 run. The latter protrude at one end of the feed belt 30 out of this to allow connection to the electrical energy source.

The flat heating element 46 Can also be used for heating floor or wall coverings by heating element 46 in corresponding modular elements, eg. As square or rectangular plates, is embedded. Such modular elements are made of a plastic material, for. B. of expanded polypropylene (EPP), which is the heating element 46 with the feed belt 30 completely encloses. The modular elements are z. B. via a tongue and groove system connected to each other and thereby also allow a continuous electrical connection of the electrical conductors 14 . 16 . 32 and 34 in adjacent modular elements by means of electrical connection elements at the opposite ends of the feed belt 30 , As for this application, a flexibility of the heating element 46 is not necessary, can be used instead of a feed belt of a textile material, a dimensionally stable feed strip of a thermoplastic or elastomeric plastic, which is made by means of an injection molding or extrusion process.

Flat heating elements according to the present invention can also be used in heatable containers. An embodiment of such a heatable container 60 is in the 5 shown in a partially broken view. The 6 shows the planar heating element 62 that in the container 60 integrated, in expanded form.

The container 60 is cuboid with a rectangular bottom 64 and four perpendicular to the ground 64 extending, in pairs parallel walls, with two shorter walls 66 and two longer walls 68 available.

The floor 64 and the walls 66 and 68 of the container 60 consist of a foamed or expanded plastic material such. B. EPP, in the the flat heating element 62 is completely embedded. The heating element 62 is located as close as possible to the interior of the container 60 facing surfaces of the soil 64 and the walls 66 and 68 so that through the heating element 62 generated heat predominantly to the interior of the container 60 is discharged and the plastic material the container 60 isolated to the outside. The container 60 is particularly suitable for keeping food warm.

The heating element 62 which areas for the ground 64 and for the walls 66 and 68 of the container 60 includes, can with a single feed belt 70 be supplied with electrical energy. The feed belt 70 is essentially like the feed belt 10 according to the 1 constructed and includes a woven band 12 and a first electrical conductor 14 and a second electrical conductor 16 with contact sections 22 respectively. 24 , The feed belt 70 is along the for the shorter walls 66 and the floor 64 certain areas of the heating element 62 so arranged on this and sewn with this, that the contact sections 22 and 24 with the power supply lines 50 of the heating element 62 perpendicular to the feed belt 70 run, in electrically conductive contact. Due to the flexibility of the feed belt 70 can the heating element 62 without problems to the shape of the container 60 be adjusted.

The ends of the electrical conductors 14 and 16 are with electrical connection elements 72 respectively. 74 connected to the top of one of the shorter walls 66 are arranged. About the connection elements 72 and 74 can the heating element 62 connected to an external power source (ie to the positive and negative poles) and thereby the interior of the container 60 be heated. Such a connection may, for. B. via the socket in a motor vehicle, wherein the connection elements 72 and 74 may also include a corresponding connection cable.

The arrangement of the connection elements 72 and 74 at an upper edge of the wall 66 offers the particular advantage of having a rechargeable battery in a lid for the container 60 can be integrated (in the 5 not shown). In this case, corresponding connection elements are arranged on the cover, which are in the closing of the container 60 with the connection elements 72 and 74 come into engagement and electrical contact between the accumulator and the electrical conductors 14 and 16 in the feed belt 70 produce. The capacity of the accumulator should be designed so that the container 60 can be heated for a few hours.

In addition, further connection elements at the opposite ends of the electrical conductors 14 and 16 be provided (in the 5 not shown), in which case the connection elements 74 and 74 are designed for the connection of the accumulator and the other connection elements for connection to an external power source. When the lid is placed, the container can then be used at the same time 60 heated and charged the accumulator.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - EP 1554911 B1 [0004, 0074]

Claims (46)

Feed belt or strip ( 10 ; 30 ; 70 ) for supplying a flat heating element ( 46 ; 62 ) with electrical energy, wherein the band or strip ( 10 ; 30 ; 70 ) is formed substantially from an electrically insulating material and at least a first and a second electrical conductor ( 14 . 16 ) which are spaced apart in the longitudinal direction of the band or the strip ( 10 ; 30 ; 70 ) and surrounded by the insulating material; at predetermined intervals along the belt or strip ( 10 ; 30 ; 70 ) each have a plurality of first and second contact sections ( 22 . 24 ) are arranged, in which the first and second electrical conductor ( 14 . 16 ) from one side of the tape or strip ( 10 ; 30 ; 70 ) is accessible; and wherein the first contact sections ( 22 ) with respect to the second contact sections ( 24 ) are offset in the longitudinal direction. Feed belt or strip ( 10 ; 30 ; 70 ) according to claim 1, wherein the distances between adjacent first contact sections ( 22 ) and between adjacent second contact sections ( 24 ) are each substantially the same. Feed belt or strip ( 10 ; 30 ; 70 ) according to claim 2, wherein the second contact sections ( 24 ) in each case in the middle between two adjacent first contact sections ( 22 ) are arranged. Feed belt or strip ( 10 ; 30 ; 70 ) according to one of the preceding claims, wherein the distances between adjacent first contact sections ( 22 ) and between adjacent second contact sections ( 24 ) are in the range of about 5 to about 20 cm, in particular in the range of about 8 to 15 cm. Feed belt or strip ( 10 ; 30 ; 70 ) according to one of the preceding claims, wherein the contact sections ( 22 . 24 ) have a length of about 3 to about 15 mm, in particular from about 8 to about 12 mm. Feed belt or strip ( 10 ; 30 ; 70 ) according to one of the preceding claims, wherein the electrical conductors ( 14 . 16 . 32 . 34 ) are formed of a metallic material, in particular of copper or silver. Feed belt or strip ( 10 ; 30 ; 70 ) according to claim 6, wherein the electrical conductors ( 14 . 16 . 32 . 34 ) comprise a metal profile, a metal band, a metal mesh or a stranded wire. Feed belt or strip according to one of the claims 1 to 6, wherein the electrical conductors through a conductive Coating are formed. Feed belt ( 10 ; 30 ; 70 ) according to one of the preceding claims, wherein the electrically insulating material comprises a textile material. Feed belt ( 10 ; 30 ; 70 ) according to claim 9, wherein the textile material is a woven, knitted or knitted band (12) or a non-woven band. Feed belt ( 10 ; 30 ; 70 ) according to claim 10, wherein the electrical conductors ( 14 . 16 . 32 . 34 ) in each case in longitudinally extending, tubular areas ( 18 . 20 . 36 . 38 ) of the woven, knitted or knitted ribbon ( 12 ) or the nonwoven tape are received. Feed belt ( 10 ; 30 ; 70 ) according to claim 11, wherein the tubular regions ( 18 . 20 . 36 . 38 ) weaving, knitting or knitting into the ribbon ( 12 ) are incorporated. Feed belt ( 10 ; 30 ; 70 ) according to claim 11 or 12, wherein the electrical conductors ( 14 . 16 . 32 . 34 ) in the tubular areas ( 18 . 20 . 36 . 38 ) are held non-positively. Feed belt ( 10 ; 30 ; 70 ) according to one of claims 11 to 13, wherein the band ( 12 ) two opposite edge regions ( 26 ), between which the tubular areas ( 18 . 20 . 36 . 38 ) for the electrical conductors ( 14 . 16 . 32 . 34 ) are arranged. The feed belt of claim 14, wherein one of the edge regions is widened so that when folding the tape along a in the longitudinal center line of the widened Edge area above the tubular areas for the electrical conductors and over the opposite edge area to come to rest. Feed belt according to one of claims 9 to 15, wherein the contact portions through recesses of the textile Materials are formed on one side of the band. Feed belt ( 10 ; 30 ; 70 ) according to one of claims 9 to 15, wherein the contact sections ( 22 . 24 . 40 . 42 ) are formed by the fact that the electrical conductors ( 14 . 16 . 32 . 34 ) pass through the textile material. Feed belt ( 10 ; 30 ; 70 ) according to one of claims 9 to 17, wherein the textile material is made of synthetic and / or natural fibers, in particular of polyesters, polyamides or mixtures thereof. Feed belt ( 10 ; 30 ; 70 ) according to claim 18, wherein the textile material is flame-retardant. Feed belt ( 10 ; 30 ; 70 ) according to one of claims 9 to 17, wherein the textile material is made of glass fibers. Feed belt or strip ( 10 ; 30 ; 70 ) according to one of the preceding claims, wherein the band or strip ( 10 ; 30 ; 70 ) further comprises a third and a fourth electrical conductor ( 32 . 34 ) which are spaced apart in the longitudinal direction of the band or the strip ( 10 ; 30 ; 70 ) and surrounded by the insulating material; at predetermined intervals along the belt or strip ( 10 ; 30 ; 70 ) each have a plurality of third and fourth contact sections ( 40 . 42 ) are arranged, in which the third and fourth electrical conductors ( 32 . 34 ) from one side of the tape or strip ( 10 ; 30 ; 70 ) is accessible, such that when folding or buckling of the tape or the strip ( 10 ; 30 ; 70 ) along a longitudinal centerline ( 44 ) in each case a third contact section ( 40 ) on a second contact section ( 24 ) and a fourth contact section ( 42 ) on a first contact section ( 22 ) comes to rest. Feed belt or strip according to one of the preceding Claims, wherein the band or bar is one or more extending in the longitudinal direction of the band or bar Signal lines includes. Feed rail according to one of the claims 1 to 8, 21 or 22, wherein the electrically insulating material a Plastic material comprises, in particular a thermoplastic or an elastomer. Feed rail according to claim 23, wherein the bar by a sheathing of the electrical conductors with the plastic material produced by an injection molding or extrusion process is. Feed rail according to claim 23 or 24, wherein the Contact sections through recesses of the plastic material one side of the bar are formed. Feed rail according to one of the claims 23-25, wherein the bar has a lower portion and an upper portion Area includes, over a flexible area in the longitudinal direction connected to each other, wherein the first and the second electrical Ladder are arranged in the lower area, and wherein the upper Area is pivoted so that it is in a closed position the bar over the contact sections of the first and second electrical conductor comes to rest. Feed rail according to claim 26, wherein the bar comprises one or more closure elements, by means of which the bar can be fixed in the closed position. Feed rail according to claim 27, wherein the closure elements each near the contact sections of the first and of the second electrical conductor are arranged. Feed rail according to one of the claims 26 to 28, wherein in the upper area a third and a fourth electrical conductor are arranged. Flat heating element ( 46 ; 62 ), comprising a plurality of substantially parallel power supply lines ( 50 ) and a feed belt or feed rail ( 10 ; 30 ; 70 ) according to one of the preceding claims, wherein each power supply line ( 50 ) with at least one contact section ( 22 . 24 ) of the first or the second electrical conductor ( 14 . 16 ) of the feed belt or the feed bar ( 10 ; 30 ; 70 ) is in electrically conductive contact. Flat heating element ( 46 ; 62 ) according to claim 30, wherein the feed belt or the feed rail ( 10 ; 30 ; 70 ) substantially perpendicular to the power supply lines ( 50 ) is arranged. Flat heating element ( 46 ; 62 ) according to claim 30 or 31, comprising a grid, braid, fabric or the like coated with an electrically conductive material ( 48 ) into which the power supply lines ( 50 ) are incorporated at regular intervals. Flat heating element ( 46 ; 62 ) according to any one of claims 30 to 32, wherein the electrically conductive material comprises graphite and a polyurethane. Flat heating element ( 46 ; 62 ) according to one of claims 30 to 33, wherein the power supply lines ( 50 ) Comprise copper or silver wires or strands. Flat heating element according to one of the claims 30 to 34, wherein the power supply lines one of an edge of the heating element, on which the feed belt or the feed bar is arranged, survive. Use of a flat heating element ( 46 ; 62 ) according to one of claims 30 to 35 for heating upholstered furniture, motor vehicle seats, interior trim of motor vehicles, mattresses, seating and lying underlay or electric blankets. Modular element for a floor or wall covering of a plastic material, comprising a flat heating element according to one of Claims 30 to 35, which is embedded in the plastic material. The modular element of claim 37, wherein the plastic material comprises a foamed or expanded plastic, in particular expanded polypropylene (EPP). A modular element according to claim 37 or 38, wherein the modular element comprises connecting elements which form an and / or non-positive connection of multiple modular Enable elements. Modular element according to one of the claims 37 to 39, wherein the feed belt or the feed bar in the modular element is arranged so that when connecting several modular elements the electrical conductors in adjacent modular Each elements are in electrically conductive contact. Modular element according to claim 40, wherein the electrical Ladder at their opposite ends respectively corresponding to each other have electrical connection elements. Heatable container ( 60 ) of a plastic material, comprising a flat heating element ( 70 ) according to one of claims 30 to 35, which is embedded in the plastic material. Heatable container ( 60 ) according to claim 42, wherein the container ( 60 ) a floor ( 64 ) and at least one wall extending transversely from the floor ( 66 . 68 ), and wherein the planar heating element ( 70 ) both in the ground ( 64 ) as well as in the at least one wall ( 66 . 68 ) is embedded. Heatable container ( 60 ) according to claim 42 or 43, wherein the container ( 60 ) electrical connection elements ( 72 . 74 ), each with an electrical conductor ( 14 . 16 ) are connected. Heatable container ( 60 ) according to one of claims 42 to 44, wherein the container ( 60 ) comprises an accumulator. Heatable container ( 60 ) according to claim 45, wherein the container ( 60 ) comprises a lid, in which the accumulator is integrated.