EP2736304A1 - Heating fabric - Google Patents

Abstract

The fabric (10) consists of multiple electrically conductive threads (62,64) that are extended along a warp direction and a weft direction. The cord strands (30,50) comprises cords (32,52) extended along and connected to a portion of the electrically conductive threads. A pair of hollow weave portion (20,40) formed of multiple cavities (26,46) is extended along a portion of the respective cords. A pair of insulating separation layer (34,54) is introduced into the cavities of the hollow weave portions.

Description

The invention relates to a heating fabric according to the preamble of claim 1. Such a heating fabric comprises threads running in the warp direction and in the weft direction, at least part of the threads being designed as electrically conductive threads.

Heating fabric of this type are used for example for seat heaters in vehicles. To generate heat, a voltage is applied to the electrically conductive threads. The electrical resistance of the filaments generates heat that is used to heat the seat.

To produce a planar heating of the heating fabric, the electrically conductive threads can be arranged in different ways. For example, it is known to guide at least one electrically conductive thread meandering along the Heizgewebes. However, there is the problem here that at a transection of the filament, the entire heating effect fails.

A surface heating element with a plurality of each consisting of a group of electrically conductive filaments heating bands, which are interconnected via plate-shaped connecting means is in the EP 1 835 786 A1 described. The interconnection of the individual heating strips also results in a substantially meander-shaped course, whereby targeted areas with heating power and without heating power can be created.

DE 42 33 118 A1 describes a heating mat with a fabric formed of carbon fibers, which forms a flexible resistance material and in which flexible contact wires, which constitute the electrodes, are incorporated. By applying a voltage is generated between the contact wires along the resistance material a heating effect.

The invention has for its object to provide a heating fabric, which provides a reliable heating effect and is flexibly dimensioned.

The object is achieved by a heating fabric with the features of claim 1. Preferred embodiments of the heating fabric are given in the dependent claims.

According to the invention, at least one pigtail runs along the heating fabric, which is connected to at least a part of the electrically conductive threads, and that in the region of the pigtail, a hollow fabric section is formed with a cavity extending along the pigtail.

A first basic idea of the invention can be seen in the fact that a pigtail, which serves to connect the electrically conductive threads to a voltage source, is introduced into the heating fabric. According to the invention, the pigtail extends along a surface formed by the heating fabric, that is to say in the plane formed by the heating fabric. For example, the pigtail may be incorporated into the tissue or applied to a tissue surface.

The pigtail is conductively connected to at least a portion of the electrically conductive strands to connect the electrically conductive strands to the voltage source. The connecting leads, which can also be referred to as connection electrodes, serve for the common connection of the electrically conductive threads to the voltage source.

A second basic idea of the invention is to design the heating fabric in the region of the pigtail as a hollow fabric. The hollow tissue section comprises at least two separate layers of fabric and a channel-shaped cavity extending between the layers of fabric in a longitudinal direction along the fabric. The pigtail extends along the longitudinal direction of the hollow tissue section or the cavity.

Through the hollow tissue section two mutually insulated or isolatable tissue areas are provided. In this way, electrically conductive threads Crossing the pigtail without contacting by the pigtail is disposed on one of the fabric layers and extend the electrically conductive threads on the respective other fabric layer. For example, a portion of the electrically conductive threads or one of the pigtail opposite end of an electrically conductive thread can be performed on the pigtail over to a mutual-pole voltage connection.

In a heating section of the heating fabric adjoining the hollow fabric section, the fabric is preferably designed as a single layer. The heating fabric is preferably designed as a single layer on both sides of the longitudinally extending hollow fabric section.

In the present case, threads are understood as meaning all linear, textile structures which can be processed into fabrics, in particular yarns, wires and mono- and multifilaments

A preferred embodiment of the invention consists in that at least one first pigtail and at least one second Pigtail are provided and that in the region of the first pigtail a first hollow tissue section and in the region of the second pigtail a second hollow tissue section is formed. Preferably, one of the connecting leads forms a positive pole and the other pigtail forms a negative pole. In this way, electrically conductive threads can pass electrically without contact or at least with reduced contact on both connecting leads. Further, it is possible to make the electrical connections on one side close to each other.

The connecting leads can also be provided on a common hollow fabric section. Due to the hollow space between the fabric layers, the connecting wires can be spatially separated from one another and thus insulated from one another.

By virtue of the at least one hollow fabric section according to the invention, two oppositely polarized connecting strands can be arranged on one and the same edge region of the region of the fabric to be heated. The heat is then generated not so between the two leads, but beyond both leads. The electrical connection is made only from one side of the heating area. In this way, it is ensured that the surface of the heating fabric to be heated largely can be cut free. The heating fabric can thus be dimensioned particularly flexible.

The connecting leads can in principle be arranged at any point of the fabric. However, the connecting strands preferably extend along an edge region of the fabric, in particular at a small distance from a side edge of the fabric. They preferably run along an edge of the heating fabric, at the edge of a region to be heated. Preferably, the at least two pigtails of different polarity are arranged parallel and / or at a small distance from one another, wherein the region between the pigtails is preferably unheated.

An improved conductivity along the pigtail can be generated by providing at least one pigtail strand comprising a plurality of pigtails. Thus, a plurality of connecting leads are combined to form a stranded strand strand, which serves as an electrode for the electrically conductive threads. As a result of the overall enlarged cross-section of the pigtail device thus formed, a more uniform heating power along the length of the heating fabric, that is to say along the pigtails, can be ensured. An improved conductivity can also be achieved by using one or more films as connecting leads in addition to or instead of wires or filaments. The film may in particular be drawn into the hollow fabric.

As electrically conductive material for the at least one pigtail is, for example, copper or silver into consideration. For example, a pure copper or silver strand can be provided. It is also possible to use a conductive coated thread, for example a silver-plated, tinned or nickel-plated copper strand.

For improved electrical separation of the two layers of the hollow tissue section, an insulating separating layer can be introduced into the cavity. The insulating separating layer, for example an insulating film, ensures that even with a spatial approximation of the two layers of the hollow tissue section, For example, by a tensile load of the fabric, a reliable insulation is maintained.

A further preferred embodiment of the invention consists in that the insulating separating layer is conductively coated on at least one side. The separating layer is preferably conductively coated on a side facing the connecting strands. In this way, the conductivity of the feed, so the electrode, increased again, and it can feed losses are reduced. The conductive coating may for example be formed by a flexible printed circuit board. If both connecting leads (plus and minus) are arranged on the same hollow tissue section, the insulating separating layer can also be conductively coated on both sides. Incidentally, a one-sided conductive coating is preferred.

In terms of production, it is preferred that the connecting wires run in the warp direction.

The electrically conductive threads preferably run transversely to the connecting strands, ie in the weft direction.

It may also be provided a reverse design, in which the connecting strands are guided with the hollow fabric section in the closing direction and the conductive threads in the warp direction, so as to achieve a separation from the plus / minus strands. Next can be provided for better contacting of the individual threads / yarns and a leno weave (leno weave) in which a wrap is given.

A particularly preferred embodiment of the invention provides that a first pigtail is connected to a plurality of first, electrically conductive threads and a second pigtail to a plurality of second, electrically conductive threads. The electrically conductive threads preferably extend into a surface of the heating fabric to be heated and are each electrically conductively connected either to the first pigtail or to the second pigtail. Along the surface of the heating fabric to be heated, the electrically conductive threads can be connected to one another, for example, by a high-impedance conductor medium.

A first basic idea of this embodiment can be seen in distributing a plurality of electrically conductive threads in the heating fabric, which supply leads for a resistance medium in which the relevant part of the heat is generated. In this case, a first part of these supply lines, the positive pole and another part of the negative terminal of a circuit. About the high-impedance resistance medium between the first supply lines and the second supply lines of the circuit is closed.

The heat generation thus takes place significantly between the electrically conductive threads in the high-impedance resistance medium. Due to the preferably uniformly distributed in the surface to be heated supply lines and the high compared to the resistance medium conductivity of the supply leads, a uniform heat effect can be generated in the heating fabric.

Another aspect is to connect all electrically conductive threads of the same polarity (plus or minus) each to a common pigtail or stranded wire unit. A first group of electrically conductive threads is thus connected to a first pigtail, which for example forms a positive pole, and a second group is connected to a second pigtail, which then forms the negative pole. The threads do not contact the respective other pigtail, so that there is an electrical separation between the plus threads and the minus threads. The electrically conductive threads are therefore each connected to only one of the connecting leads (plus or minus).

By means of the at least one hollow fabric section, the selective connection of the electrically conductive threads with the first or the second pigtail can be realized reliably by passing the threads on the non-contact pigtail on the respective other fabric layer of the hollow fabric section. The electrically conductive threads preferably run parallel to one another and do not contact each other in this way.

If both pigtails are arranged on a hollow fabric section, the electrically conductive threads can extend along the entire longitudinal or weft direction of the fabric, without contacting the transverse thereto, each opposite polarity pigtail.

The electrically conductive threads, which extend as supply lines into the region to be heated, are preferably aligned transversely to the connecting leads. In the area of the surface to be heated, the electrically conductive threads are electrically connected to one another via the high-resistance conductor medium.

A high-impedance conductor medium is understood in particular to mean a conductor medium in which heat can be generated by applying a voltage and which has a higher electrical resistance than the electrically conductive supply line threads.

Preferably, the electrically conductive threads of the first pigtail and those of the second pigtail are evenly distributed over the tissue, which is to be understood as meaning that the return lines are distributed either alternately or in another predetermined, regular sequence over the surface of the fabric. Via the high-impedance conductor medium, a multiplicity of circuits is formed along the surface of the tissue, wherein a uniform heating effect is produced by the uniform arrangement of the electrically conductive threads.

As a high-impedance conductor medium can be provided according to a preferred embodiment of the invention, at least one high-impedance thread. Preferably, a multiplicity of high-impedance filaments are arranged transversely to the electrically conductive filaments. The high-resistance filaments thus each contact a multiplicity of electrically conductive filaments, which are alternately connected to the two connecting strands or stranded strands.

For a reliable contact between high-resistance thread and the electrically conductive threads, it is preferred that the high-resistance thread is looped around by at least one pair of threads of the electrically conductive threads, wherein a first thread of the pair of yarns the high-resistance thread on a first fabric side and a second thread of the pair of yarns contacted the high-impedance thread on a second fabric side. The feeder threads in the weft direction are therefore each carried out twice, so that the high-resistance thread is better wrapped or contacted.

In a further preferred embodiment, a flat coating is provided as a high-impedance conductor medium. The planar coating, for example a resistor paste, forms the heating resistive material. As a planar coating is for example a carbon or graphene coating into consideration. The coating can also be designed as a nanotube coating. In this case, the area of the connecting strands is preferably not coated. A combination of high-impedance filaments and high-resistance fabric coating is also possible.

Fig. 1

eine erste Ausführungsform eines erfindungsgemäßen Heizgewebes;

Fig. 2

eine Querschnittsansicht im Bereich der Anschlusslitzen eines erfindungsgemäßen Heizgewebes;

Fig. 3

ein erfindungsgemäßes Heizgewebe einschließlich einer vergrößerten Ansicht eines Gewebeabschnitts;

Fig. 4

eine zweite Ausführungsform eines erfindungsgemäßen Heizgewebes;

Fig. 5

ein erfindungsgemäßes Heizgewebe mit Kabelanschluss und

Fig. 6

eine dritte Ausführungsform eines erfindungsgemäßen Heizgewebes.

The invention will be further described by means of preferred embodiments, which are shown in the accompanying schematic figures. In the figures shows:

Fig. 1

a first embodiment of a heating fabric according to the invention;

Fig. 2

a cross-sectional view in the region of the connecting strands of a heating fabric according to the invention;

Fig. 3

an inventive heating fabric including an enlarged view of a tissue section;

Fig. 4

a second embodiment of a heating fabric according to the invention;

Fig. 5

an inventive heating fabric with cable connection and

Fig. 6

a third embodiment of a heating fabric according to the invention.

Identical or equivalent components are identified in all figures with the same reference numerals.

A first embodiment of a heating fabric 10 according to the invention is shown in FIG FIGS. 1 to 3 shown. The heating fabric 10 comprises a base fabric with weft threads 12 running in the weft direction and warp threads 14 extending in the warp direction (cf. Fig. 3 ). The threads 12, 14 are designed as non-conductive threads and may for example consist of PET filaments.

In the non-conductive base fabric, a plurality of electrically conductive threads 62, 64 is woven. The electrically conductive threads 62, 64 can be made in total be formed of a conductive material or conductive coated. The electrically conductive threads 62, 64 run exclusively in one direction of the fabric, here in the weft direction along the non-conductive weft threads 12.

In the region of a side edge of the heating fabric 10, which forms a connection region 16 of the heating fabric 10, two strand strands 30, 50 are arranged. These each represent a connection electrode for the electrically conductive threads 62, 64. The strand strands 30, 50 are introduced into the fabric such that a first strand strand 30 exclusively with a group of first electrically conductive threads 62 and a second strand strand 50 exclusively with a Group of second electrically conductive threads 64 is connected. The strand strands 30, 50 each include a plurality of individual strands 32, 52, which may be embodied, for example, as copper or silver strands or as conductive coated yarns. The first connecting strands 32 are web-technically connected to the first electrically conductive threads 62. The second connecting strands 52 are web-technically connected to the second electrically conductive threads 64. In terms of binding, no second electrically conductive threads 64 make contact with the first connecting leads 32 and vice versa.

The electrical separation of the first connecting leads 32 from the second electrically conducting threads 64 and the second connecting leads 52 from the first electrically conductive threads 62 is realized in that a hollow tissue section 20, 40 is formed in each case in the region of the connecting strand strands 30, 50. For this purpose, the warp threads 14 of the fabric are pulled in such that two fabric layers 22, 24, 42, 44 are formed in the region of the hollow fabric sections 20, 40. The two fabric layers 22, 24, 42, 44 of this hollow fabric or double layer fabric sections are electrically insulated from one another.

Fig. 2 shows a cross-sectional view of the terminal portion 16 of the heating fabric 10 with its two hollow fabric sections 20, 40. The first hollow fabric section 20 has an upper fabric layer 22 and a lower fabric layer 24. The second hollow fabric section 40 has an upper fabric layer 42 and a lower fabric layer 44. The first connecting strands 32 are arranged on the upper fabric layer 22 of the first hollow fabric section 20. The second connection strands 52 are arranged on the lower fabric layer 44 of the second hollow fabric section 40. Between the fabric layers 22 and 24 or 42 and 44, respectively a cavity 26 and 46 is formed.

Again Fig. 1 2, the threads 62 electrically connected to the first connecting strands 32 extend along the upper fabric layer 42 of the second hollow fabric section 40 and the threads 64 connected to the second connecting strands 52 extend along the lower fabric layer 24 of the first hollow fabric section 20. In this way, the threads are 62 of the connecting leads 52 and the threads 64 of the connecting leads 32 are electrically isolated.

The first connecting leads 32 and the second connecting leads 52 can also be referred to as positive poles or negative poles, which are to be connected to a voltage source. To produce a circuit, the electrically conductive threads 62, 64 are electrically connected to one another along a heating region 60 or a surface of the heating fabric 10 to be heated by means of a high-resistance conductor medium. The high-resistance conductor medium, which is formed in the first embodiment of the heating fabric 10 by a plurality of high-resistance filaments 66 running transversely to the supply fibers 62, 64, generates a uniform heating over the entire heating region 60. The high-resistance filaments 66 running in the warp direction intersect the electrically conductive filaments 62, 64 and in this way produce a multiplicity of electrical circuits over the heating surface of the fabric.

Fig. 3 shows a preferred thread guide in the heating surface of the fabric. The electrically conductive threads 62, 64 are each executed in duplicate, that is, between non-conductive weft threads 12 are at least two electrically conductive threads 62 or 64, which loop around the high-resistance thread 66 on opposite sides, so that the thread 66 is looped around on both sides , Due to the paired arrangement of electrically conductive threads 62, 64 between the non-conductive threads 12, a particularly good contacting of the high-resistance threads 66 is achieved.

To provide an additional electrical isolation or insulation between plus and minus (first connecting strands 32 with threads 62 opposite to second connecting strands 52 with threads 64), one hollow space can be inserted into the hollow tissue sections 20, 40 Separator or separating layer 34, 54 introduced. The separating device 34, 54 may in particular comprise a release film, which is drawn into the heating fabric 10 along the respective hollow fabric section 20, 40. In order to improve the conductivity of the connecting leads 32, 52, the separating foil may be electrically coated on its side facing the pigtail.

A second embodiment of a heating fabric 10 according to the invention is shown in FIG Fig. 4 shown. Instead of running in the warp direction, high-resistance filaments or yarns, the heating fabric 10 is provided in the area to be heated with a high-resistance coating 68. For example, the heating fabric 10 may be coated with a resistance paste. The connection region 16, in which the connecting leads 32, 52 are arranged, is preferably not coated. Preferably, the already finished woven fabric is coated.

By connecting the strands 32, 52 to a voltage source, the power supply is distributed over the threads 62, 64 on the surface and passed into the resistive coating. In the resistance coating, the heat is generated. The distance between the threads 62, 64 is determined by the operating voltage, the resistance paste or the paste thickness and the desired heating power.

Fig. 5 shows a possibility of realization of a cable connection for the electrode wires 32, 52. In the illustrated embodiment, a plate angle 70 is clamped on the electrodes. The sheet metal bracket 70 connects all the connecting leads 32, 52 of a stranded strand 30, 50 and forms a connection device for a voltage source, not shown in the figures. Alternatively, it is also possible to introduce a conductive foil, for example a copper foil, into the cavity 26, 46 or channel and then to apply cables to the foil, for example to crimp, solder, weld or glue.

Due to the design of the heating fabric 10 according to the invention, the fabric can be cut almost as desired, without changing the surface heating power. With a rectangular design of the tissue, the tissue can be cut almost anywhere along three of the four sides. However, the connection region 16 with the connecting leads 32, 52 must not be severed.

Fig. 6 shows a way to heat a fabric with a hole 18 over its entire surface. For this purpose, two Gleichpolige connecting strands 32, 52 are provided on opposite tissue areas or fabric edges in each case. Although individual electrically conductive threads 62, 64 are cut through the hole 18, the heating fabric 10 is heated along the entire heating region 60. For this purpose, the electrically conductive threads 62 are electrically conductively connected to first connecting leads 32 arranged on opposite sides of the hole 18. The second electrically conductive threads 64 are connected to two corresponding connection strands 52 on opposite sides of the hole 18. As with the other embodiments, the pigtails 32, 52 may be embodied as pigtails strands 30, 50. If there are several holes in the same line, there should be more intermediate pigtails to ensure power between adjacent holes.

By using elastic and / or textured, electrically conductive threads 62, 64 and elastic weft yarns (for example Lycra), a unidirectional heating fabric can be produced.

The invention provides a heating fabric which can be cut particularly flexible. This is achieved in that the connecting leads are not arranged on opposite sides of the fabric or its heating area, but on one and the same side, so that the fabric or the heating area can be largely cut free, apart from the area of the connecting strands. The heating effect in the surface of the fabric is created by connecting the pigtails respectively to separate, electrically conductive threads which extend into the surface of the fabric. The contacting of the electrically conductive threads via a high-impedance conductor medium in which due to its electrical resistance of the relevant part of the heat is generated.

Claims (11)

Heating fabric with threads running in the warp direction and in the weft direction, wherein at least a part of the threads is designed as electrically conductive threads (62, 64),
characterized, - That along the heating fabric at least one pigtail (32, 52) extends, which is connected to at least a portion of the electrically conductive threads (62, 64), and - That in the region of the pigtail (32, 52), a hollow fabric section (20, 40) with a along the pigtail (32, 52) extending cavity (26, 46) is formed. Heating fabric according to claim 1,
characterized, - That at least a first pigtail (32) and at least one second pigtail (52) are provided and - That in the region of the first pigtail (32) a first hollow tissue section (20) and in the region of the second pigtail (52), a second hollow tissue section (40) is formed. Heating fabric according to claim 1 or 2,
characterized,
in that at least one strand strand (30, 50) is provided, which comprises a plurality of stranded wires (32, 52). Heating fabric according to one of claims 1 to 3,
characterized,
in that an insulating separating layer (34, 54) is introduced into the cavity (26, 46). Heating fabric according to claim 4,
characterized,
that the insulating separating layer (34, 54) is conductively coated on at least one side. Heating fabric according to one of claims 1 to 5,
characterized,
that the connecting wires (32, 52) extend in the warp direction. Heating fabric according to claim 6,
characterized,
in that the electrically conductive threads (62, 64) extend in the weft direction. Heating fabric according to one of claims 1 to 7,
characterized, - That a first pigtail (32) with a plurality of first, electrically conductive threads (62) and a second pigtail (52) with a plurality of second, electrically conductive threads (64) is connected, which in a surface to be heated of Heating fabric extend into it, wherein the electrically conductive threads (62, 64) in each case either with the first pigtail (32) or with the second pigtail (52) are electrically connected, and - That the electrically conductive threads (62, 64) along the surface to be heated of the heating fabric are interconnected by a high-impedance conductor medium. Heating fabric according to one of claims 1 to 8,
characterized,
that the high-impedance conductor medium comprises at least one high-impedance filament (66). Heating fabric according to one of claims 1 to 9,
characterized,
that the high-resistance thread (66) is looped around by at least one pair of threads of the electrically conductive threads (62, 64), a first thread of the pair of yarns connecting the high-resistance thread (66) on a first fabric side and a second thread of the pair of threads the high-resistance thread on one contacted second tissue side. Heating fabric according to claim 10,
characterized,
that the high-impedance conductor medium comprises a surface coating (68).

Images