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US 4,360,803 AGranted
Door lock assembly with electrical alarm
AssigneeAug. Winkhaus GmbH & Co. KG
InventorBernd Heiland
Life of this patent
Estimating the term…
Abstract
A door lock assembly having an electrical alarm system includes a piezoelectric element located between the lock bolt of the door lock and the lock frame in order to emit a signal to energize the electrical alarm system when pressure is applied between the lock bolt and the frame.
Claims15
A door lock assembly for a door comprising:
- a lock frame;
- a lock bolt which is movable into locking position with said lock frame;
- and electrical alarm means responsive to pressure on said lock bolt for generating an alarm signal;
- said electrical alarm means comprising a piezoelectric element arranged between said lock bolt and said lock frame in the region of the locking end of said lock bolt on the side thereof which is located in the direction of movement toward said locking position.
1 more element
Dependencies are inferred from the claim text.