The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 29, 1978
Filed:
Dec. 20, 1977
James G Allemann, Santa Ana, CA (US);
Michael W Grey, South Gate, CA (US);
Norris Industries, South Gate, CA (US);
Abstract
A security type dead bolt for a door is arranged so that a key must be used on the inside, as well as on the outside, to extend the dead bolt to locked position, in that way to prevent an unauthorized person opening the door from the inside after surreptitious entry. To make certain that when the occupant is at home and with the latch bolt extended by the inside key to locked position, there can be no lost key situation blocking exit by the occupant in case of an emergency such as a fire, the dead bolt mechanism is arranged to trap the key in the lock whenever the dead bolt is extended to locked position, but to release the key when withdrawn. A yieldable mechanism permits unlocking the latch bolt from the outside even when a key is left in the lock on the inside.