Types of Police Locks
– Floor-mounted police lock
– Consists of a steel bar running at a 45° angle from the center of the door to the floor
– Slots or fixtures secure the steel bar in place
– Designed by Emiel Fox and patented in 1907
– Manufactured under the brand name Police Lock
– Provides high security and is difficult to break with physical force
– Crossbar police lock
– Features two steel bars across the width of the door
– Bars are held by brackets set in the doorframe
– Bars can be moved inwards to unlock the door
– Associated with New York City in the 20th century
– Still made and imported from China
History and Development of Police Locks
– Floor-mounted locks designed for wooden doors
– Superseded by metal doors and doorframes
– Fox Police Lock Company played a significant role
– Locks have become genericized to some extent
– Police locks seen in movies set in old New York City
Advantages of Police Locks
– Provide considerable security
– Harder to break than deadbolts
– Require partial destruction or removal of the door to defeat
– Suitable for securing damaged doors
– Used in police procedures for door security
References
– Gregory Byer’s article ‘When the Deadbolt Was Not Enough’
– Daniel B. Schnieder’s article ‘Still Barring the Door’
– Information about the original style of Fox Police Lock
– Wikipedia page on police locks
– Categories of locks, American inventions, and 20th century in New York CitySources: https://en.wikipedia.org/wiki/Police_lock
