Voltage-leveling monolithic self-regulating heater cable
US10470251B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 1, 2017 |
| Grant date | Nov 5, 2019 |
| Priority date | — |
| Expiry date | Nov 7, 2037 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05B2203/02
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A self-regulating electric heater cable includes a monolithic heater core of PTC material encapsulating a pair of bus wires, and a conductive layer disposed on an outer surface of the heater core such that the conductive layer levels the voltage generated at the outer surface of the heater core when an electric current is passed through the bus wires. The conductive layer draws the current evenly through lobes of PTC material encapsulating the bus wires. The conductive layer may be a coating, such as a conductive ink or paint, or may be an extruded or wrapped material applied to the heater core. Standard heater cable layers are applied over the conductive layer, including an electrically insulating layer that contacts a portion of the conductive layer and also may be separated, at points, from the conductive layer by one or more air gaps.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.