Coil assembly
US4236139A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 13, 1979 |
| Grant date | Nov 25, 1980 |
| Priority date | — |
| Expiry date | Feb 13, 1999 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05B3/64
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A coil assembly is formed by an elastic metal wire helical extension spring coil having convolutions resiliently urged towards each other and held apart by spacers pinched between the convolutions and held there by the spring-back of the convolutions. The spacers can interspace the coil convolutions and be made to extend radially inwardly and outwardly beyond the inside and outside of the coil, so as to radially space the coil from a coil center and the inside of a tubular casing enclosing the coil. In this way a tubular radiant heater can be made by using electric resistance wire to form the coil and making the spacers from refractory insulating material.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.