Patent · US Expired

Coil with protection against overheating

US4112405A · kind A · utility

30Cited by
6References
7Claims
0Family size

Inventor

Key dates

Filing dateAug 16, 1976
Grant dateSep 5, 1978
Priority date
Expiry dateAug 16, 1996

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01F2027/406
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A plastic coil bobbin has a recess with the precise dimensions of a thermal fuse. On one side, the recess is open so that, as the coil is wound on the bobbin, successive layers of coil wire form a wall-like surface closing that open side. As the fuse is press fit into the recess, it is also forced into intimate contact against the wall of wire. Thus, the only material between the fuse and wire is a thin plastic shell forming the fuse housing. Since the fuse rating takes this wall thickness into account, there is effectively no thermal insulation between the coils and the fuse. Accordingly, under overheating conditions, the fuse opens a circuit when there is overheating and before a fire can start.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.