Abstract: A locking device for doors and the like, having a bolt installed in the door frame and movable into the open position by a solenoid and into the shut position by a spring. Locking devices of this kind have not found general use, since there is no room in the frame for a device as required by the regulations wherewith the lock may be opened mechanically from the inside. This problem has been solved in such a manner that the socket of the door has a counterbolt forced by a spring against the bolt proper, whereby the spring force of the spring of the counterbolt is smaller than the spring force of the spring of the bolt.

Abstract: A safety device for doors comprising a cylindrical housing going through to the door, a locking pin to be locked in the housing and a chain one end of which is locked to the pin and the other end being attached to the door frame. The housing is attached to the door by means of two flanges, one on each side of the door, the spacing of which is adjustable.