Patent · US Expired

Door exit-delaying means

US5035450A · kind A · utility

21Cited by
10References
13Claims
0Family size

Assignee

Inventor

Key dates

Filing dateFeb 23, 1990
Grant dateJul 30, 1991
Priority date
Expiry dateFeb 23, 2010

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T292/699
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

In a first embodiment, the invention has a casing set in the frame of a door in confronting relationship to the latchbolt-confining housing of the door. A bolt, translatable in the casing, is extended, by a solenoid, and enters the housing to prevent opening of the door. A latchbolt position sensor, in the form of a dual-ended limb, monitors the position of the latchbolt. Upon withdrawal of the latchbolt, from latching closure of the door, the limb actuates a switch to operate a time delay circuit component. When the specified time delay set by the component has run its course, it cuts power to the solenoid. Compression springs withdraw the bolt from the latchbolt-confining housing, to permit the door to open.

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