Method for the production of an electrically conductive resistive layer and heating and/or cooling device
An electrically conductive resistive layer is produced by thermally spraying an electrically conductive material onto the surface of a non-conductive substrate. Initially, the material layer arising therefrom has no desired shape. The material layer is then removed in certain areas so that an electrically conductive resistive layer having said desired shape is produced.
1. A method for producing a heater, the steps comprising:
applying an electrically conductive material onto a non-conductive substrate by accelerating and spraying unmolten particles of the electrically conductive material onto the non-conductive substrate at a temperature below a melting temperature of the electrically conductive material to cause micro-welding between the unmolten particles and the non-conductive substrate, wherein the electrically conductive material is applied to form an electrically conductive material layer having no desired shape; and
removing a portion of the electrically conductive material layer in partially removed areas such that an electrically conductive resistive heating layer is formed having a desired shape.
2. The method according to claim 1 wherein the removing of the electrically conductive material layer is done via a laser beam, a water jet or a powder blasting process.
3. The method according to claim 1 further comprising the step of at least indirectly detecting the current value (WIST) of the electrical resistance for the electrically conductive resistive layer during the removing of the areas of the electrically conductive resistive heating layer.
4. The method according to claim 3 further comprising the step of comparing the current value (WIST) of the electrical resistance for the electrically conductive resistive heating layer with a target value (WSOLL) and removing additional area of the electrically conducting material to change the current value such that the difference between the current value (WIST) and the target value (WSOLL) is reduced.
5. The method according to claim 4 further comprising the step of simultaneously obtaining the current value (WIST) of the electrical resistance of the electrically conductive resistive heating layer and the reduction of the difference between the current value (WIST) and the target value (WSOLL).
6. The method according to claim 1 wherein the material layer is removed such that at least at one spot of the electrically conductive resistive heating layer possesses a predetermined melting spot that functions as a melting fuse.
7. The method according to claim 1 wherein the material layer is removed in such a way that the electrically conductive resistive heating layer is meander-shaped.
8. The method according to claim 1 further comprising the step of applying a non-conducting intermediate layer onto the electrically conductive resistive heating layer after the removed areas and subsequently applying another electrically conductive material layer over the non-conducted intermediate layer via thermal spraying and subsequently removing areas of the another electrically conductive material layer such that a second electrically conductive resistive heating layer is formed which has the desired shape.
9. The method according to claim 1 wherein the electrically conductive material comprises bismuth, tellurium, geranium, silicone and/or gallium arsenide.
10. The method according to claim 1 wherein the electrically conductive material is applied to fire plasma spraying, high-speed flame spraying, arc spraying, autogenously spraying, laser spraying or cold spraying.
11. The method according to claim 1 further comprising the step of sealing the electrically conductive resistive heating layer.
12. The method according to claim 11 wherein the sealing is performed via silicone, polyimide, or water glass.
13. The method according to claim 11 wherein the sealing is performed under vacuum.
14. The method according to claim 1 wherein the non-conductive substrate comprises glass.
15. A tubular flow heater comprising:
a non-conductive tubular substrate; and
an electrically conductive resistive heating layer applied onto the substrate,
wherein the electrically conductive resistive heating layer comprises an electrically conductive material that is at first applied surrounding the tubular substrate by accelerating and spraying unmolten particles of the electrically conductive material onto the non-conductive tubular substrate at a temperature below a melting temperature of the electrically conductive material to cause micro-welding between the unmolten particles and the non-conductive tubular substrate, areas of the electrically conductive resistive heating layer being subsequently removed such that a desired shape is obtained.
16. A heating plate comprising:
a non-conductive substrate; and
an electrically conductive resistive heating layer applied onto the substrate,
wherein the electrically conductive resistive heating layer comprises an electrically conductive material that is at first applied over the substrate by accelerating and spraying unmolten particles onto the non-conductive substrate at a temperature below a melting temperature of the electrically conductive material to cause micro-welding between the unmolten particles and the non-conductive substrate, areas of the electrically conductive resistive heating layer being subsequently removed such that a desired shape is obtained.