Patent · US Expired

Double swinging latchbolt

US3970339A · kind A · utility

14Cited by
2References
14Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 15, 1975
Grant dateJul 20, 1976
Priority date
Expiry dateJan 15, 1995

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T292/106
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

There is disclosed a latchbolt assembly which replaces conventional rectilinear latchbolt movement with dual direction swinging movement to reduce binding forces and which uses two independently operable dead latches in association with the dual swinging motions of the latchbolt. To facilitate release, as by key or panic bar actuation, the load of the latchbolt mass and friction is substantially eliminated by coupling the release system to one of the dead latches and thereafter utilizing camming action derived from the opening of the door to swing the latchbolt out of its keeper. Thus hard pressure against the door will not hamper the release. The second dead latch is operated by a latch feeler finger which frees the latchbolt only when the door is open thereby to facilitate relatching by swinging into the keeper as the door closes.

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