Patent · US Expired

Electrically operable strike

US4867496A · kind A · utility

47Cited by
18References
13Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMar 14, 1988
Grant dateSep 19, 1989
Priority date
Expiry dateMar 14, 2008

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T292/705
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

A fire rated electrically operable strike in which a pivotable keeper is prevented from pivoting by a locking member which is spring biased into a position in which pivoting of the keeper is prevented until the locking member is moved from its normal, locking position by the electrical energization of a solenoid which actuates an armature connected to the locking member. The locking member has a recess into which a spring biased ball extends when the locking member is in its locking position. The materials from which the ball and its mounting are made and the relative dimensions thereof are selected so that when the temperature to which the strike is subjected is greater than normal, such as by reason of a fire, but less than a temperature at which the locking member biasing spring is ineffective, the ball expands and the mounting for the ball changes size so that the ball cannot retract from the recess in the locking member, and the locking member is held in its keeper locking position.

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