Patent · US Expired

Combination spring/dead bolt lock

US4255953A · kind A · utility

22Cited by
4References
18Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 2, 1979
Grant dateMar 17, 1981
Priority date
Expiry dateMay 2, 1999

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T292/0983
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

One part of a key-in-knob lock set functions in a normal manner such that when the lock set is unlocked, either the outside or inside knob can be manipulated to open the door by withdrawing the latch bolt from a normal spring latch extended position. When, instead, the lock set is locked, the latch bolt is extended an exceptionally long distance into the frame to a dead bolt position. Extension and retraction of the latch bolt to and from dead bolt position is accomplished by manipulation of a main cam through the agency of a key in the outside knob or a turn button on the inside knob. For withdrawing the latch bolt from the normal spring latch extended position an escutcheon housing for the outside knob or a corresponding escutcheon housing for the inside knob serves, by moving transversely of the axis of rotation of the knob, to rotate a radially extending finger on the spindle which, acting through the main cam, withdraws the latch bolt. By rotation of the key in the outside knob, or the turn button on the inside knob, the spindle is rotated a greater amount, far enough to have the main cam extend the latch bolt an additional distance to the dead bolt position. In that deadbolt …

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