Patent · US Expired

Electrical control

US4112274A · kind A · utility

6Cited by
9References
40Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 4, 1976
Grant dateSep 5, 1978
Priority date
Expiry dateFeb 4, 1996

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01H2019/143
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

An electrical control for providing a graduated change in the magnitude of electrical energy transferred from a source of electrical energy to a device driven thereby including a mount, a plurality of load contacts disposed in fixed relation on the mount, a movable power contact engaging certain of the plurality of load contacts, a movable transition contact associated with the movable power contact first engaging each of the load contacts engaged by the movable power contact to provide an alternate full load current path through each of the load contacts engaged by the movable power contact prior to engagement by the movable power contact, thus providing a transition between the load contacts engaged by the movable power contacts which are connected to differing magnitudes of impedance substantially without arcing; and a third movable contact may be provided for selectively engaging other of the plurality of load contacts for effecting a switching function.

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