DE10320379A1 - A method for manufacturing heating elements in many different forms has conductive material flame sprayed on to a suitably shaped substrate material with an insulating layer - Google Patents

Abstract

The heating element, typically a radiant heater (4), has a profiled substrate with conductive material (2), typically copper, projected accurately by thermal-kinetic means, such as flame spraying, to suitable cross-sectional dimensions and covering with an insulating layer (6).

Description

The The invention relates to an electrically heatable element and a Method of making such an element.

electrical Heated elements are used in many areas of application. Heating wires and heating cables are used for heating, the heat in operation dispense, whereby the element is heated. The heat transfer from the heating wire to the Element can be over Heat conduction, thermal radiation or about heat convection respectively.

The Efficiency of heat transfer is, however, generally not satisfactory, since between the heating wire and the element usually do not have a full-surface and ideal contact exists and thus a large part of warmth lossy about Transfer heat convection becomes. Furthermore, the setting of a desired heating output is at given cross-sectional geometry of the heating wire essentially only over the choice of materials possible. However, this requires only limited settings for the Heating capacity. In addition, the assembly is usually quite complex, because the heating wire or the heating cable in a separate process step must be connected to the element to be heated.

The The invention is based on the object of being easy to manufacture specify heatable element with high efficiency.

The Task is solved by a heatable element in which directly on a surface of the Elements a heating track made of an electrically conductive material and predetermined electrical heating power using a thermal kinetic application process is applied.

The decisive advantage of such a heated element is to see that the heating track is sprayed directly onto the element, that at least in the area of the surface layer a material There is a connection between the heating track and the element. The heating track is therefore a part and in particular an integral part of the element to be heated. This is a heat transfer through heat conduction between the heating track and the element with high efficiency. Another major advantage is that the heating track through the spraying process in a simple manner and with little effort can be applied to the element. So that is the manufacturing cost for the heated element kept very low.

Under a beam-bound thermal-kinetic application process generally understood an application process in which a particle stream, namely the electrically conductive material to be applied, in particular Copper particles, with kinetic energy and after adding heat is directed to the element. Such a procedure will also referred to as thermal spraying, as it is listed in DIN 32530. For a targeted application can Apertures, electromagnetic fields or so-called jacketed flows are provided his. The beam leaves yourself through these measures therefore focus sufficiently so that preferably on the use no covers or masks are used. The term thermal is to be understood to mean that the particles of the particle stream in particular soften, melt or melt, or that they warmed at least so far that they are a thermal change in the surface of the Elements. This is thermal change of the surface for example reducing the surface hardness, softening or that Melt the surface. The term kinetic is understood to mean that the momentum the particle is high enough so that when it hits it the surface in this - if necessary softened surface - at least partially pressed.

In WO 02/068245 is such a beam-bound application process for generating conductor tracks for described the motor vehicle sector. The steps described here to apply the conductor track can also on the generation transferred to the heating track.

As The so-called flame spraying method is particularly suitable. In this spraying process, the material to be applied is used for the heating track while of the spraying process at least partially melted. When it hits on the surface of the element, the material to be applied combines with the material of the element intimately, so that in particular a material connection is trained. With flame spraying is a very quick and economical application with comparatively low technical Effort possible.

Next so-called cold gas spraying is also suitable for flame spraying. This process is also known as beam plating. at In this process, the particles to be applied bounce at a very high rate kinetic energy on the element. The particles are there partially accelerated to the speed of sound or above.

The particular advantages of the spraying process, in particular flame spraying, lie in the simple process control, the quick opening Carrying speed, the possibility of direct application to any two- and three-dimensional surface geometries, which can be both flat and curved.

In dependence The heating track can be selected without further pretreatment the surface can be applied directly to the element. It is one in particular chemical-free treatment of the element possible. Even the individual Heating tracks individually and discreetly solely by focusing of the particle beam are generated without masks or covers required are.

At the In a preferred embodiment, the heating track is generated Heating output preferably by selecting at least one of the following Parameters set: thickness of the heating track, width of the heating track, Material density (degree of filling) of the Heating track, proportion of oxidation in the material of the heating track and material composition the heating track. The flame spray process therefore offers a wide range of setting options, with which the heating power can be influenced. This are the geometrical data of the heating track, which in simple For example, by expanding / focusing the particle beam and / or overmold several times can be varied easily in wide ranges. About the Application speed, i.e. the speed at which the particle beam shifted relative to the element can also affect the Material density of the heating track can be taken. The setting options are sufficient here from a porous Layer to a largely dense layer. Another way of influencing consists in the choice of the oxidation portion of the heating track. This will set that the spraying process completely, partially or not at all in a protective gas atmosphere takes place. Depending on the extent to which contact of the Particle beam with atmospheric oxygen is allowed to vary Proportion of the oxidized particles. Another way of influencing can be seen in the material composition. With flame spraying almost any materials can be applied. In particular can also mixtures of different materials, especially metals, optionally mixed with non-conductive impurities, in can be applied in a single spraying process.

In an expedient embodiment is in particular by this activities the heating power of the heating track to a value between 0.1 and 500 Watts set per meter.

by virtue of the comparatively poor heat transfer with conventional Heating wires is a very high electrical energy is necessary. in many areas of application, For example, the heating of gutters, the heating wires are therefore usually with a tension in the order of magnitude acted upon by 230 volts. The difference is in a preferred one Design provided that the heatable element for a voltage in the range between 1 and 24 volts, in particular 3, 6 or 12 volts is designed. These low voltage values will not last due to the high heat transfer values reached between the heatable and the element to be heated.

On This is suitable due to the problem-free application of the heating track Spraying method in a preferred embodiment also for application the heating track on an endless element, in particular an extruded one or extruded element. The heating track is preferred directly during the manufacturing process of the endless element applied. For example, the heating track is immediately after the Extrusion process and partially sprayed before cutting the element.

In In an expedient embodiment, the heating track is applied to a building material element. Under Building material element are generally understood here elements that in connection with the construction of buildings both indoors and outdoors be used. This applies, for example, to slabs and tiles or other indoor flooring as well as outdoors, such as plates for Courtyard entrances, sidewalks and the like. Furthermore, the Building material elements also roof surface elements as well as installation elements such as cable or installation shafts understood. The heatable elements are used here, for example, the surfaces to clear snow and ice (roof areas, solar panels, courtyard entrances, Walkways) or to air-condition the interior of the building (heatable Wall elements, heated floor coverings).

Special advantages result from the application of the heating track to channel-like or tube-like elements, particularly in the case of gutters. Gutter heating is currently carried out using wired heating elements. These are subjected to high voltage and high currents and are surrounded by several layers of insulation. This complex construction alone means that the costs are very high. In addition, there are considerable installation costs, since the heating elements must be attached to the gutter using special brackets. In addition, especially in downpipes, the heating elements narrow the flow cross-section for the rainwater running off. They therefore form mechanical resistances that can easily catch leaves and other dirt. In contrast, she has The heating track applied to the spraying process has the decisive advantage that it only applies insignificantly and thus does not constitute an obstacle. The rainwater can therefore flow off unhindered.

at the use of commercially available thermoplastic Plastic roof gutters, the heating track is preferred without previous Treatment sprayed on immediately. Because of the thermoplastic Plastic properties and the thermal-kinetic application a good cohesive Connection reached. When using gutters made of conductive material, made of copper, for example, is alternatively preferred Variant first an electrically insulating base layer or an electrically insulating Base layer sequence applied, which forms the surface of the element which is then applied to the heating track. Here, too, there is a material connection via the Base layer with the element instead. The base layer is thereby preferably already selective and the intended course of the heating track applied accordingly. The base layer can also be used as a seed layer can be called, which acts as a kind of adhesion promoter layer, if the cohesive Connection of the sprayed-on particles with the untreated surface of the Elements is insufficiently achieved. As an alternative to the application a seed layer, for example by a first flame spraying process is generated, the surface of the element can also be treated appropriately become. For this the surface is for example mechanically roughened, or by chemical or heat treatment in their adhesive properties selectively prepared. These preparatory measures related the application of the heating track or the creation of a base layer can Naturally generally be provided for heatable elements.

substantial In comparison, savings can also be made with the Achieve formation of heatable floor or wall surfaces. Here too a significant simplification in manufacturing and a significantly higher energy yield achieved that the heating track directly on the back, for example of tiles, slabs or other floor coverings. With conventional In contrast, underfloor heating the heating elements are embedded in the screed, only then the panels are laid.

Further advantageous configurations and areas of application for building material elements are in the dependent claims resigned.

According to one Another preferred application is the heating track to a temperature Vessel, in particular applied to a chemical reactor vessel. Temperable vessels are about that in addition, for example, transport or storage containers for gases, liquids or solids as well as food and are also used in chemical Laboratories.

In An alternative application is the heating track on a functional element applied. Such are among heatable functional elements Understand elements that perform a specific function, where the heatability of the functional elements and their functionality guaranteed. examples for such functional elements are display boards, traffic signs, mirrors, especially in the automotive sector, other optical elements such as lenses, Telescopes and parabolic antennas or windshield wipers in the automotive sector. In the variant of the heated windshield wiper, the heating track is preferably immediate provided on or in the wiper rubber.

According to one Another preferred area of application is the heating track applied to a comfort element. Comfort elements are understood to mean such elements, at which are particularly comfortable for the user due to the heatability results. Such elements are, for example, seats or Sitzele elements both indoors and outdoors (Park benches, heated armrests in the automotive sector, heated handles and buttons and steering wheels).

Farther is the heating track in a preferred variant on an outer element applied to a vehicle. Among vehicles here are general Understand modes of transport on land, water and in the air. The exterior elements are for example the wings of an airplane, the rudder or rudder components for boats etc.

According to one The heatable element is a particularly preferred embodiment Heating or warming plate. The heated element therefore takes place in particular also in the field of household appliances, for example for keeping warm of food and drinks Commitment.

The Object is according to the invention still resolved by a method for producing an electrically heatable Elements with the features of claim 16. The related advantages and preferred listed with the heatable element embodiments apply mutatis mutandis to the procedure. Preferred variants of the method are laid down in the subclaims. The following are exemplary embodiments the invention explained in more detail with reference to the figures. Each show in roughly simplified representations:

1A . 1B a heated gutter,

2A . 2 B Variants for heated pipes,

3 building a floor covering with heated panels,

4 a heated endless element, such as a rail,

5 a heated shaft,

6 a heated wall or roof surface, such as brick or solar panels,

7 a temperature-controlled vessel, for example a chemical / thermal mechanical reactor vessel,

8th a temperature-controllable transport or storage container as a further example for a temperature-controlled vessel,

9 a heatable functional element, such as a display board, traffic sign, mirror,

10 a heated door lock,

11 a heated parabolic bowl,

12 a heated door handle,

13 a heated steering wheel,

14 a heated button,

15 a heated outer element of a vehicle and

16 a hot plate.

In the individual figures are elements with the same effect with the same Provide reference numerals.

For all embodiments, when applying a heating track 2 on the surface of a respective base or support element using the flame spraying method to form a heatable element, as a rule, proceed as follows: the material to be sprayed is fed to an injection head of an injection mold. In the spray head, the material to be applied is at least softened or melted by the application of heat and then emerges from the spray head as a particle beam. This is bundled and focused in particular by panels, so that discrete heating tracks 2 be generated. The spray head is moved relative to the element. When the material hits the surface, it connects intimately and in particular integrally with the element. The heating track 2 therefore becomes an integral part of the heating element. Depending on the surface properties, the surface is pretreated, if necessary a base layer or seed layer is applied first, possibly as an adhesion promoter layer. The heating track is then on this 2 generated and then with a protective layer, in particular an electrical insulation layer 6 overdrawn. By choosing the spray parameters, such as application rate, application speed, focus, use of protective gas, use of the material to be sprayed, etc., the resulting heating power of the heating track 2 set. The heating track 2 can be applied in a narrow band or over a large area.

The 1A and 1B show a top view of a gutter 4 or a cross-sectional view. As can be seen from this, are on the side of the gutter wall 4 from the bottom of the gutter 4 spaced two heating tracks 2 directly on the inside surface of the gutter 4 applied. The heating tracks 2 are with an insulation layer 6 overdrawn. The heating tracks 2 extend in the longitudinal direction of the gutter to a respective contact point 8th , through which the power is supplied. At these contact points 8th the gutter is, for example, perforated and designed in the manner of a plug socket, so that the heating track can be inserted by inserting an appropriate connecting line 2 can be supplied with electricity. The gutter 4 consists preferably of a thermoplastic on which the heating track 2 is applied immediately without pretreatment. The heating track 2 is preferably applied directly during the manufacturing process of the gutter, which is produced as an extruded endless element. For heating the gutter 4 becomes the heating track 2 with a voltage of, for example, only 3 volts. The heating tracks are in the area of downpipes 2 in particular pulled sideways without the opening cross-section of the opening in the gutter 4 is reduced towards the downpipe. In the downpipe itself there are preferably also heating tracks 2 intended.

Examples of heatable pipes 10 are from the 2A . 2 B can be seen, according to 2A the pipe 10 an externally heated full pipe and the pipe 10 according to 2 B an internally heated pipe consisting of two half-shells 12A, B is.

The heating tracks are also here 2 directly on the pipe 10 (on the outside in the embodiment according to 2 and on the inside according to the embodiment 2 B ) applied and then from an insulation layer 6 or surrounded by an insulation jacket.

The 3 shows in cross section the structure of a floor covering, in which on a floor 14 , for example a screed or a concrete floor, first individual contact bridges 16 are arranged, on which the actual walkable flooring, for example tiles 18 is hung up. The contact bridges 16 are similar to the tiles plate-shaped elements, from the surface tapered contact pins 20 step out, which are in electrical connection with each other. On these contact pins 20 become the tiles 18 placed at the bottom with the insulation layer 6 coated heating track 2 exhibit. When laying the tiles 18 becomes the insulation layer 6 from the contact pins 20 pierced like a piercing contact and the heating track 2 contacted. This measure takes place when laying the tiles 18 quasi automatically the continuous contacting of the heating tracks 2 instead of. There is a connection contact jumper for connection to a power supply 22 provided a contact point 8th having.

Instead of plate-shaped elements, heated elongated elements, such as a rail, can also be used 24 , be provided, which is shown schematically in 4 is illustrated. After that is at the bottom of the rail 24 the heating track is applied as a flat layer, each with a contact point on its edge sides 8th which is designed as a contact line extending into the plane of the paper.

5 shows in cross section an embodiment of a heatable shaft 26 , in which, for example, installation pipes, hoses, supply lines or electrical cables are routed. The shaft is formed from a basic body 28 and an overlapping cover closing this 30 , Both on the main body 28 as well as on the lid 30 are heating tracks in different places on the inside as well as on the outside 2 with contact points 8th arranged, each by the installation layer 6 are covered.

In the 6 is a heated roof surface - comprising several roof elements 32 - shown. These roof elements 37 are, for example, brick or side of the roof element 32 applied flat heating track 2 with the contact points 8th and the insulation layer 6 , For attachment to a support part 34 are supporting elements 36 intended. In the same way, a heatable wall surface consisting of individual heatable wall elements (plates) can also be constructed.

The in the 1 to 6 The exemplary embodiments shown all relate to building material elements which are used both indoors and outdoors when building buildings. Through the training as heatable building material elements with the heating track usually sprayed on the back 2 cost-effective heatable elements are made available for the construction sector due to the simple manufacturing process. Particularly due to the direct and in particular material connection to a base or support element, a particularly high level of mechanical robustness is achieved because - in contrast to heating wires or heating cables - the heating tracks 2 cannot get caught and cannot tear.

In the embodiments according to the 7 and 8th heatable vessels are illustrated, whereby after 7 it is in particular an externally heated chemical reactor 38 in which chemical processes take place at a certain temperature. The temperable container according to 8th particularly provides a storage container 40 for example for transport or storage purposes. This container 40 is heated both inside and outside in the embodiment. Just like with the reactor 7 is the construction with the sprayed heating track 2 , the contact points 8th and the insulation layer 6 intended. In the with the reference numerals 38 and 40 designated temperature-controllable vessels, for example, liquids, gases or solids are heated or heated.

Another area of application for the formation of heatable elements by applying the heating track 2 are functional elements, some of which are exemplary in the 9 to 11 are shown. In 9 is schematically a display board 42 , such as a traffic sign or the like. Which shows the heating track on its rear 2 having. The structure of the heated display panel basically corresponds to the structure of the heated roof elements 32 according to 6 , The same structure can also be provided for a heatable mirror, for example an outside mirror in the motor vehicle sector, etc.

10 shows a heatable door lock as an embodiment 44 , on the outside of the cylinder of the door lock 44 the heating track 2 with the contact frames 8th is applied.

Another functional element is in 11 a heated parabolic bowl 46 shown.

Another area of application is heatable comfort elements, some of which are exemplified in the 12 to 14 are shown. According to claim 12 is a heated handle 48 provided, in which the load-bearing basic element 50 of the door handle 48 with a heating track 2 is provided. The basic element 50 with the heating track attached to it 2 is from the insulation layer 6 completely covered, which also forms the handle surface accessible from the outside.

According to 13 is a heated steering wheel 52 provided in the case of the load-bearing basic element 50 first the heating track 2 , then the insulation layer 6 and then a particularly foamed steering wheel jacket 54 is applied.

According to 14 is a heatable button 56 provided which in one shot 58 in the direction of the arrows 60 is kept mobile. The button 56 is on a touch side accessible from the outside with the insulation layer 6 coated heating track 2 provided, both on the inside and on the outside.

Another preferred area of application is the heating of external elements 62 for vehicles and airplanes. Because with the Flamecon process the heating track can be used on any complex surface 2 External elements can be applied 62 with almost any surface contours with the heating track 2 or with several heating tracks 2 be provided and thus as heatable outer elements 62 be formed. An example of this is shown schematically in the 15 illustrated. Such external elements 52 are, for example, the wings of aircraft that can be defrosted if necessary due to the heatability.

Because of the simple and inexpensive design, the described method can be used to form heatable elements easily and inexpensively, particularly in the field of household goods. This applies in particular to a warming or heating plate 64 how this in 16 is shown. The hot plate 64 is formed by a heat-conducting plate 66 , on the underside of the heating track 2 with the contact points 8th and the insulation layer 6 is provided. The hot plate 64 also has a base 68 on.

2

heating track

4

gutter

6

insulation layer

8th

Contact rack

10

pipe

12a, b

shells

14

ground

16

Contact bridge

18

tile

20

pin

22

Connection contact bridge

24

rail

26

shaft

28

body

30

cover

32

roof element

34

supporting part

36

supporting member

38

reactor

40

Storage containers

42

scoreboard

44

Locks

46

parabolic dish

48

Handle

50

basic element

52

steering wheel

54

handlebar coat

56

button

58

admission

60

arrow

62

male member

64

heating plate

66

Heat conductive plate

68

pedestal

Claims (29)

Electrically heated element (e.g. 4 . 10 . 18 ...) characterized in that directly on a surface of the element (e.g. 4 . 10 . 18 ...) a heating track ( 2 ) is applied from an electrically conductive material and with a predetermined electrical heating power with the help of a beam-bound thermal kinetic application process. Heated element (e.g. 4 . 10 . 18 ...) according to claim 1, characterized in that the heating track ( 2 ) has a heating output between 0.1-500 W / m. Heated element (e.g. 4 . 10 . 18 ...) according to claim 1 or 2, characterized in that the heating track ( 2 ) is designed for a voltage in the range between 1-24V. Heated element ( 4 . 10 . 26 ) according to one of the preceding claims, characterized in that the element ( 4 . 10 . 26 ) is manufactured as an endless element. Heated element ( 4 . 10 . 18 . 26 . 32 ) according to one of the preceding claims, characterized in that the heating track ( 2 ) on a building material element ( 4 . 10 . 18 . 26 . 32 ) is applied. Heated element ( 4 . 10 ) according to claim 5, characterized in that the heating track ( 2 ) on a channel or tube-like element ( 4 . 10 ), especially a gutter ( 4 ), is applied. Heated element ( 18 ) according to claim 5, characterized in that the heating track ( 2 ) on a floor element ( 18 ) or a wall element is applied. Heated element ( 18 ) according to claim 6, characterized in that the heating track ( 2 ) on an underside of the floor element ( 18 ) is applied, and that for contacting two adjacent floor elements ( 18 ) on a common contact bridge ( 16 ) are placed, which electrically connected contact pins ( 20 ), each with the heating track ( 2 ) of the respective floor element ( 18 ) to contact. Heated element ( 26 ) according to claim 5, characterized in that the heating track ( 2 ) on a shaft ( 26 ) is applied for hoses or cables. Heated element ( 32 ) according to claim 5, characterized in that the heating track ( 2 ) on a roof element ( 32 ) is applied. Heated element ( 38 . 40 ) according to one of claims 1 to 4, characterized in that the heating track ( 2 ) on a heatable vessel ( 38 . 40 ), especially on a reactor vessel ( 38 ), is applied. Heated element ( 42 . 44 . 46 ) according to one of claims 1 to 4, characterized in that, the heating track ( 2 ) on a functional element ( 42 . 44 . 46 ) is applied and that the heatability of the functional element ( 42 . 44 . 46 ) to ensure its functionality. Heated element according to claim 12, characterized in that the heating track ( 2 ) is applied to a wiper, in particular to a wiper rubber. Heated element ( 48 . 52 . 56 ) according to one of claims 1 to 4, characterized in that the heating track ( 2 ) on a comfort element ( 48 . 52 . 56 ) is applied and that the heatability of the comfort element ( 48 . 52 . 56 ) provides increased comfort for a user. Heated element according to one of claims 1 to 4, characterized in that the heating track ( 2 ) on an outer element ( 62 ) of a vehicle is applied. Heated element ( 64 ) according to one of claims 1 to 4, characterized in that the heating track ( 2 ) to form a heating or warming plate ( 64 ) on a heat conducting plate ( 66 ) is applied. Method for producing an electrically heatable element (e.g. 4 . 10 . 18 ...), characterized in that directly on a surface of the element (e.g. 4 . 10 . 18 ...) a heating track ( 2 ) is applied from an electrically conductive material and with a predetermined electrical heating power using a beam-bound thermal-kinetic application process. A method according to claim 17, characterized in that the heating track ( 2 ) is applied using flame spraying. Method according to claim 17 or 18, characterized in that the heating power is set by selecting at least one of the following parameters - thickness of the heating track ( 2 ) - width of the heating track ( 2 ), - material density of the heating track ( 2 ), - proportion of oxidation in the material of the heating track ( 2 ), - material composition of the heating track ( 2 ). Method according to one of claims 17 to 19, characterized in that that the heating power is set to a value between 0.1-500 W / m. Method according to one of claims 17 to 20, characterized in that on the heating track ( 2 ) a protective layer ( 6 ) is applied. Method according to one of claims 17 to 21, characterized in that on the element (eg 4 . 10 . 18 ...) at least in the area of the heating track to be applied ( 2 ) a base layer is first applied, on which the heating track ( 2 ) is applied. Method according to one of claims 17 to 22, characterized in that the element ( 4 . 10 . 26 ) is manufactured as an endless element and that the heating track ( 2 ) is applied to the endless element. Method according to one of claims 17 to 23, characterized in that the heating track ( 2 ) on a building material element ( 4 . 10 . 18 . 26 . 32 ) is applied. Method according to one of claims 17 to 22, characterized in that the heating track ( 2 ) on a heatable vessel ( 38 . 40 ), especially on a reactor vessel ( 38 ) is applied. Method according to one of claims i 7 to 23, characterized in that the heating track ( 2 ) on a functional element ( 42 . 44 . 46 ) is applied and that the heatability of the functional element ( 42 . 44 . 46 ) to ensure its functionality. Method according to one of claims 17 to 23, characterized in that the heating track ( 2 ) on a comfort element ( 48 . 52 . 56 ) is applied, and that the heatability of the comfort element ( 48 . 52 . 56 ) provides increased comfort for a user. Method according to one of claims 17 to 23, characterized in that the heating track ( 2 ) on an outer element ( 62 ) a vehicle is applied. Method according to one of claims 17 to 22, characterized in that the heating track ( 2 ) to form a heating or warming plate ( 64 ) on a heat-conducting plate ( 66 ) is applied.