Glow plug having a series connection of resistant filaments
US5091631A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 21, 1989 |
| Grant date | Feb 25, 1992 |
| Priority date | — |
| Expiry date | Jul 21, 2009 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF02B1/04
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A glow plug for an air compressing internal combustion engine of the type having a tube which is closed at one end and connected to a plug housing on an opposite end with a wire filemant-like resistance element disposed in an insulating material within the tube and formed two series-connected resistance filaments, of which the rear resistance filament, serves as a regulating filament, having a higher positive temperature resistance coefficient than the front resistance filament, which serves as a heating filament, is improved so as to enable the heating up time to be reduced without adversely impacting upon the effective life of the glow plug. In accordance with various embodiments, this result is achieved through the use of, for example, special alloys for the material of the regulating filament which have a resitance at 1000.degree. C. that is greater than their resistance at 20.degree. C. by a resistance ratio over about 7.5:1, and preferably greater than 12:1, and in particular, about 14:1.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.