Positive temperature coefficient heater with distributed heating capability
US4931627A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 13, 1989 |
| Grant date | Jun 5, 1990 |
| Priority date | — |
| Expiry date | Jul 13, 2009 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05B3/845
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A heating device for a mirror includes a substrate having an electrical buss system deposited on one surface thereof including a plurality of interdigitated electrodes and two buss bars. There is provided a plurality of heater-lets formed of an electrically resistive layer of material having a positive temperature coefficient. The plurality of heater-lets have varying sizes and shapes and are deposited over the electrical buss system between the adjacent electrodes of the interdigitated electrodes. Each of the plurality of heater-lets are separated from its neighbor by spaces of varying sizes and shapes so as to form a plurality of individual heating areas of variable intensity. A first adhesive layer is deposited over the resistive layer and adheres to the exposed areas of the substrate. An electrical barrier layer is secured to the first adhesive layer, and a second adhesive layer is disposed on the electrical insulated barrier layer. A removable protective covering is secured to the second adhesive layer. The power distribution over the entire substrate is selectively regulated by varying the density of the heater-lets.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.