Patent · US Expired

Ratchet means switch operator

US4788520A · kind A · utility

4Cited by
9References
4Claims
0Family size

Assignee

Inventor

Key dates

Filing dateSep 24, 1987
Grant dateNov 29, 1988
Priority date
Expiry dateSep 24, 2007

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01H13/58
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A switch operator has a low friction ratchet wheel driven by a low power time programmed clock to operate the switch in one position or another depending upon the position of the ratchet wheel to operate the ratchet wheel independent of the time programmed clock. A pawl resiliently held and biased away from the ratchet wheel engages the ratchet wheel when moving in a forward direction to move it a predetermined amount. A cam member mounted adjacent the ratch wheel is engaged by the pawl to bias the pawl against a projection on the ratchet wheel when the pawl is moved forward and to bias the pawl away from the ratchet wheel upon its return movement.

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