Patent · US Expired

Apparatus for operating a door latching and unlatching device

US4305612A · kind A · utility

54Cited by
3References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 24, 1978
Grant dateDec 15, 1981
Priority date
Expiry dateJul 24, 1998

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T292/57
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

An apparatus for operating a door-latching and -unlatching device includes a thumbturn, a barrel cam, a shaft for coupling the thumbturn to the barrel cam to cause rotation of the barrel cam in response to movement of the thumbturn, a follower for the barrel cam and apparatus attaching the follower to the latch bolt to cause the latch bolt to move in response to actuation of the barrel cam. The illustrative barrel cam includes two generally diametrically opposed cam lobes such that rotation of the thumbturn either clockwise or counter-clockwise retracts the latch bolt. The follower includes a bar which lies against the cam surface of the barrel cam, and the latch bolt moving apparatus includes an actuator arm which is pivotally mounted adjacent one of its ends, the follower pin being mounted intermediate the actuator arm ends, the follower pin being supported adjacent the barrel cam, and the actuator arm further including a roller retractor actuator adjacent its other end.

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