Patent · US Expired

Silicon controlled rectifier trigger circuit

US4333019A · kind A · utility

8Cited by
10References
17Claims
0Family size

Inventor

Key dates

Filing dateMay 7, 1980
Grant dateJun 1, 1982
Priority date
Expiry dateMay 7, 2000

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03K17/725
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

A silicon controlled rectifier trigger circuit is responsive to an input AC voltage and provides at least one drive pulse per switch activation to a load circuit. Such load circuit advantageously includes an electric stapler or an electric brad driver. Such trigger circuit generally comprises: a two-position switch; first and second capacitors; first and second Zener diodes; a transistor; and a silicon controlled rectifier. The drive pulse is provided to the load circuit when the switch is in its second position; the first capacitor is charged by the input AC voltage when the switch is in its first position; the first Zener diode and the transistor are conductive when the input AC voltage is greater than a first predetermined value; the first and second Zener diodes are conductive and the transistor is non-conductive when the input AC voltage is greater than a second predetermined value; the second capacitor is interposed between the first Zener diode and the transistor; the silicon controlled rectifier is conductive when the transistor is conductive and when the switch is in its second position to provide the drive pulse to the load circuit. According to specific embodiments of th…

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