US Patent 11702864 Automatic locking-deadbolt assembly in a door

A lock assembly for a door includes a lock body having a housing with at least one deadbolt supported in the housing for movement between a retracted position and an extended position and biased toward the extended position by a spring, and a trigger mechanism mounted on the door separate from the lock body for engagement with a door jamb upon closure of the door, said trigger mechanism being adapted to hold the at least one deadbolt in the retracted position when the door is open in opposition to a spring bias, and to permit movement of the at least one deadbolt to the extended position upon engagement of the trigger mechanism with the door jamb.