Patent · US Expired

Normally closed switch

US4119821A · kind A · utility

3Cited by
3References
1Claims
0Family size

Assignee

Inventor

Key dates

Filing dateSep 26, 1977
Grant dateOct 10, 1978
Priority date
Expiry dateSep 26, 1997

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01H1/242
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A switch case has a top provided with a central opening in which slides the stem of a plunger that has a foot inside the case. A bridging contact spring has a central portion engaging the foot and has free end portions extending away from opposite sides of the foot to form movable contacts normally engaging stationary electric contacts in the case beneath the movable contacts. Between each stationary contact and the central portion of the spring there is a fulcrum member beneath a movable contact so that when the central portion of the spring is moved downwardly by depressing the plunger, the movable contacts will rock on the fulcrum members and lift away from the stationary contacts.

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