DE202004012054U1 - Electrical heating unit for vehicle seat, has bundles of heating sections, which are arranged at distance from each other in order to avoid electrical contact between bundles, where sections are electrically connected with electrodes - Google Patents

Abstract

The unit (1) has two electrodes (5, 5`) for supplying current to the unit. Bundles (9, 9`, 9``, 9```) of heating sections (11, 11`, 11``) are arranged at a distance from each other in order to avoid an electrical contact between the bundles. The heating sections are arranged on a part of a base area (4), which is to be heated and over coated between the electrodes, and electrically connected with the electrodes.

Description

The The present invention relates to a heating element after Preamble of claim 1. Generic heating elements are, for example. used for heating vehicle seats.

State of technology

Out DE 41 01 290 a heating element is known in which a plurality of mutually non-contacting heating conductors is arranged between two electrodes. A disadvantage of this embodiment is that in case of a breakage of a heat conductor of the swept by this heating conductor part of the surface to be heated can no longer be heated. Is particularly unfavorable when the heating element is to be sewn, because a large number of heating conductors can be damaged by the sewing needle.

Out DE 101 12 405 a heating element is known in which a plurality of interconnected heating conductors is laid between two electrodes. In the event of a break of a heating conductor, the interconnection of the heating conductors with each other leads to a deflection of the current around the break point. Thus, despite a breakage of a heating conductor, this heating element will continue to heat the surface to be heated homogeneously. The problem, however, is that in a fraction of an electrode just by networking the heating element with each other undesirable current concentrations can occur at the electrode break point. This can lead to overheating in this area.

object the invention

Around to get to a heating element, the fail-safe, safer across from Consequential damages and Furthermore is better overseeable, the subject-matter of claim 1 is proposed. A division of heating strands into different bundles, which do not contact each other electrically, ei nerseits sufficient Redundancy over the failure of a single Heizstranges. On the other hand, it is ensured that an uncontrolled power line in the event of electrode breakage not to local overheating to lead can.

Under a bunch is not just a summary of single strands in here an elongated one Overall arrangement of approximately circular cross-section Understood. Hereinafter, a bundle of heating strands is understood a number of heating strands, which within an at least mentally spatially delimitable elongated Range are arranged, functionally and / or spatially as belonging together are to be considered, and / or at least in relation to their overall course roughly along are arranged to each other.

One Heating element with a bundle of at least three heating strands according to claim 2 ensures that the bundle still conductive remains, even if a pin hit unfavorably a crossroads of two heating strands destroyed.

One Heating element according to claim 3 has robust, functional heating strands.

One Heating element according to claim 4 avoids durchzeichnende, thick Heizleiterbündel.

One Heating element according to claim 5 has Heizleiterbündel, the very well überähbar and fail-safe are.

One Heating element according to claim 6 also has a flat, by fabrics not felt through height on.

One Heating element according to claim 7 allows the Formation of different redundant arrangements.

One Heating element according to claim 8 is inexpensive to produce.

One Heating element according to claim 9 or 10 is particularly failsafe despite suturing.

characters

The only 1 shows an embodiment of the present invention, an electric heating element 1 , This embodiment is only to be understood as an example.

Description of the invention

1 shows a heating element 1 , This has a carrier layer 3 on. The carrier layer 3 is preferably made of a textile material, such as. B. a knitted fabric or a felt fabric. It has rectangular dimensions in the present case. Along the longitudinal edges of the carrier layer 3 are two electrodes 5 . 5 ' arranged. The electrodes are, for example, by electrically conductive threads, electrically conductive adhesive, electrically conductive films, combinations thereof o. Ä. Formed.

The electrodes 5 . 5 ' are each at one of their ends via a power supply line 7 . 7 ' connected to a power / voltage source (not shown).

Bundles run at an angle to the electrodes 9 . 9 ' . 9 '' , ... of heating strands 11 . 11 ' . 11 '' , In the present case, these are bundles 9 , ... perpendicular to the Electrodes arranged. They are on the carrier layer 3 arranged. Preferably, they are fixed there with adhesive. However, you can also hung up, sewn or z. B. be acted upon.

The individual bundles 9 , ... of heating strands 11 . 11 ' , ... run in the present example straight from an electrode 5 to the other electrode 5 ' , However, they can also meandering, curved or guided in any other way.

The bundles 9 , ... of heating strands 11 , ... preferably do not touch each other. Conveniently, there are a sufficient number of bundles 9 , ... provided to a base to be heated 4 between the electrodes 5 . 5 ' is intended to heat evenly.

The bundles 9 , ... of heating strands 11 , ... are preferably meandering on or within a band-like strip 20 arranged. The stripe 20 can be formed by a fabric pad, an adhesive tape o. Ä. However, it can also be a purely conceptual limitation of the space in which the heating strands 11 , ... a heating bundle 9 , ... are arranged.

The heating strands 11 , ... could also be zigzag, straight, or laid in any other way. It makes sense that they are at least largely spaced from each other. At least one of the heating conductors is suitably arranged so that it has a plurality of other heating strands 11 ' . 11 '' crosses and so connects 12 to other heating strands 11 ' . 11 '' manufactures.

In the present case, the heating strands 11 , ... a bundle 9 , ... wave or sinusoidal with the same "amplitude" and identical center line They are mutually offset by the proportion (1 to their number in the bundle (here 3)) of a "wave" along the central axis in the bundle ,

To fix the entire arrangement, it may be appropriate, as in the embodiment, a cover layer 2 so on the carrier layer 3 arrange that the electrodes 5 . 5 ' and the heating strands 11 , ... are embedded in between.

If the heating element is connected to power, then flows from the supply device power via the supply line 7 into the electrode 5 , Because the electrode 5 electrically significantly more conductive than the heating strands 11 , ... the heating current distributes itself evenly over the bundles connected to the electrode 9 , ... of heating conductors 11 , .... The current then flows from the electrode 5 through the heating strands 11 , ... the area to be heated 4 into the electrode 5 ' and from there via the supply line 7 ' back to the current / voltage source.

It may be expedient as shown in the embodiment, the heating element 1 to sew in a cover or similar. In such a case then runs a seam 13 for example, about the base area to be heated 4 , The course of the sewing seam can with respect to the course of the Heizleiterbündel 9 , ... be arranged at any angle α. In the present case, the sewing seam runs 13 perpendicular to the bundles 9 , ... and approximately parallel to the electrodes 5 . 5 ' , The sewing seam 13 has at least one sewing thread 14 on. The sewing seam 13 as a result of the needle puncture leads to penetration points 18 , The opening size d of the passage points 18 is essentially determined by the thickness of the sewing needles and / or the thickness of the sewing thread (s). The length s of the pinholes is from midpoint to midpoint of the points of penetration 18 measured. The distance between the edges of the passage points to each other is x. In practice, due to the small opening size of the passage, x usually corresponds approximately to the stitch length s.

To overseer the power line through a bundle 9 , ... it is necessary to ensure that at least one heating strand when sewing over 11 ,... preserved. Then the current can be transferred from damaged heating conductors to the remaining heating conductors. To achieve this, the connection points should be 12 with respect to the course of the heating strands in front of and behind the sewing seam 13 be arranged. In addition, the connection points should 12 have a distance from each other which is greater than the opening size d of the passage points 18 is. This avoids that a plurality of contact conductors can be destroyed by a single needle hit. The same purpose is served if only two heating strands per junction 11 . 11 ' intersect and at least one remaining heating string 11 '' has a minimum distance from such a junction, which is at least as large as the opening size d of a passage point 18 is.

To prevent the sewing needle a bundle 9 , ... meets several times, it is expedient, the distance x of the passage points 18 each other at least as large as the width of fine Heizstranges 11 , ..., preferably as the width b of the bundle 9 ,... to choose. This applies to an approximately rectangular over-stitching of the bundle 9 through the sewing seam 13 , In the case of a crossover at a different angle, the distance x is the passage points 18 preferably at least the product of the width b of the conductor bundle and the sine of the selected angle α.

In an alternative embodiment, not shown, it may be provided that a bundle of heating strands is repeatedly penetrated by passage points of the stitches of a sewing needle. For this Case, the number of heating strands and their arrangement within the bundle is scattered so that despite multiple penetration of the bundle in located between the passage points region of the bundle, the presence of a sufficient number of remaining heating strands is ensured.

1

heating element

2

topcoat

3

backing

4

To heated base

5, 5 '

electrodes

7, 7 '

supply lines

9 9 '

Bunch of heating sections

11 11 ', 11' '

heating section

12

junction the heating strands

13

stitched seam

14

sewing thread

15

section of the sewing thread over the carrier layer

16

section of the sewing thread under the carrier layer

18

penetrations the stitches of the sewing needle

20

band-like strip

b

width of the bunch

d

Opening size of the passage point

f

width a heating line

s

Length of pinpricks

x

distance the passage points from each other

Claims (10)

Heating element ( 1 ) with at least two electrodes ( 5 . 5 ' ) for supplying the heating element ( 1 ) with electricity, with a plurality of heating strands ( 11 . 11 ' . 11 '' ) covering at least part of a base area to be heated ( 4 ) sweeping between the electrodes ( 5 . 5 ' ) are arranged and electrically conductively connected thereto, characterized in that the heating element ( 1 ) at least two bundles ( 9 . 9 ' . 9 '' . 9 ''' ) of heating strands ( 11 , ...), and that the two bundles ( 9 . 9 ' . 9 '' ) are spaced apart from each other to allow electrical contact between the two bundles ( 9 ,...) to avoid. Heating element according to claim 1, characterized in that a bundle ( 9 , ...) at least two, preferably at least three heating strands ( 11 . 11 ' . 11 '' ). Heating element according to one of the preceding claims, characterized in that at least one heating strand ( 9 , ...) is formed at least proportionally from copper, carbon particles, carbon fibers, carbonized plastic filaments, silver, gold, polyamide and / or combinations thereof, and / or that a heating strand ( 11 , ...) comprises one or more monofilament heating conductors, one or more multifilament heating conductors, one or more insulating layers and / or one or more mechanical reinforcing devices, these components preferably parallel, concentric, zigzag meandering and / or spiraling to the direction of the Heating cables ( 11 , ...) are arranged. Heating element according to one of the preceding claims, characterized in that at least one bundle ( 9 , ...) a ribbon-like strip ( 20 ) within which the heating strands ( 11 , ...) - preferably along one another - are arranged. Heating element according to one of the preceding claims, characterized in that at least two - preferably all - heating strands ( 11 , ...) of a bundle ( 9 , ...) at least in the predominantly larger part of their course spaced from each other - preferably also spaced from any other heating strands - in the bundle ( 9 , ...) are arranged, that at least one heating line ( 11 , ...) - preferably all - a plurality of bends and / or kinks to at least one - preferably two or more - other heating conductors ( 11 ' . 11 '' ) a plurality of electrical connection points ( 12 ) to which the heating strands involved ( 11 , ...) are electrically conductively connected to each other, and which preferably substantially over the entire length of the bundle ( 9 , ...) and / or the Heizstranges ( 11 , ...) are arranged distributed, but at least in front of and behind (with respect to the running direction of the Heizstranges ( 11 , ...)) one of the Heizbündel ( 9 , ...) crossing / penetrating stitching ( 13 ). Heating element according to one of the preceding claims, characterized in that the bundle ( 9 ) a height of at most the height of three, preferably a maximum of two heating strands ( 11 ,...) having. Heating element according to one of the preceding claims, characterized in that at least two heating strands ( 11 , ...) are different in their structure and / or their material composition from each other and / or at least two are the same. Heating element according to one of the preceding claims, characterized in that the heating element ( 1 ) a carrier layer ( 3 ) - in particular of a textile material - has at least one bundle ( 9 , ...) on the carrier layer ( 3 ) or between the carrier layer ( 3 ) and a cover layer ( 2 ) and / or that at least one electrode ( 5 . 5 ' ) on the carrier layer ( 3 ) by sticking, sewing, action, stitching and / or embroidery is attached. Heating element according to one of the preceding claims, characterized in that the heating element ( 1 ) in the area of the base area to be heated ( 4 ) at least partially by a sewing seam ( 13 Sewn is that the sewing seam ( 13 ) at least one bundle ( 9 , ...) of heating strands ( 11 , ...) at an angle α crosses that the passage points ( 18 ) stitches of sewing seam ( 13 ) have an opening size (d) and distances (x) to each other that the bundle ( 9 , ...) a width (b) transverse to its longitudinal extension and in the plane of the base surface to be heated ( 4 ), that at least one heating strand ( 11 , ...) of the bundle ( 9 , ...) a width (f) transverse to its longitudinal extent and in the plane of the base surface to be heated ( 4 ) that the opening size (d) is smaller than the width (b) of the bundle ( 9 , ...) and that the distances (x) of the passages (x) 18 ) are at least as large as the width (f) of the heating strand ( 9 , ...). Heating element according to claim 9, characterized in that the opening size (d) of the penetration points ( 18 ) stitches of sewing seam ( 13 ) at least by the width (f) of a heating line ( 11 ) smaller than the width (b) of the heating bundle ( 9 , ...) and / or that the distances (x) of the passages ( 18 ) are at least as large as the width (b) of the bundle ( 9 , ...).