Patent · US Expired

Thermal overload protection apparatus for a commutator or slipring motor

US4658321A · kind A · utility

19Cited by
4References
15Claims
0Family size

Assignee

Inventor

Key dates

Filing dateAug 12, 1985
Grant dateApr 14, 1987
Priority date
Expiry dateAug 12, 2005

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02K5/148
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A thermally released switching mechanism which in a simple fashion and at a precisely defined switching point clearly interrupts the current to the motor when a preset, highest admissible temperature is exceeded, at least until the actual temperature has once against fallen below the highest admissible temperature. The thermally released switching mechanism is comprised of a lever element made of a memory element which, upon exceeding the highest permissible temperature set value, lifts the brush from a commutator or a slipring. This mechanism preferrably employs a memory element with a two-way effect. This thermal switching mechanism is suitable both for commutator motors with hammer or tubular brush holder systems as well as for slipring motors.

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