Abstract: A locking mechanism which is mountable in a door assembly including a door and a frame. The locking mechanism includes a latch belt assembly, a drive motor and a cam assembly connected to the latch bolt assembly and the drive motor by a linkage assembly. The cam assembly is driven by the motor and provides a mechanical advantage in operating the linkage assembly and the connected latch bolt. The lock mechanism includes a mechanical latch back feature which retains the latch bolt in a retracted position until the door is closed relative to the frame. Also included are switches coupled to the motor for use in controlling the motor based on the position of the cam.

Abstract: A locking system comprises a lock mechanism including a casing structure adapted to be mounted to one of a door and a door frame and having a front plate with an aperture therein; a latch bolt mounted with respect to the casing structure for movement between a first position wherein a portion thereof extends from the front plate of the casing structure for latching engagement with the other of the door and door frame, and a second, retracted position wherein the same portion thereof is held out of position for said latching engagement. A deadlock member is mounted to the casing for movement between a blocking position wherein the deadlock member will prevent movement of the latch bolt to the second, retracted position, and a non-blocking position wherein the latch bolt is free to move to the retracted position. An operating disc is rotatably mounted coaxially with the latch bolt and coupled to rotate the latch bolt through a lost motion type of connection.

Abstract: A lock mechanism includes a casing structure adapted to be mounted to one of a door and a door frame for cooperation with an apertured strike plate mounted to the other of the door and door frame. The lock mechanism further comprises a front plate for the casing structure with a pair of apertures therein and a latch bolt retractably mounted with respect to the casing structure and biased to an extended first position wherein a latching portion thereof extends from one of the front plate apertures for engagement with the strike plate aperture, and movable to a secnd retracted position. The latching portion of the latch bolt has a beveled leading surface located for engagement with the strike plate only when the latch bolt is moved a predetermined amount toward the retracted position.

Abstract: There is disclosed a secured door knob and escutcheon assembly, wherein the assembly is protected against tampering and unauthorized removal from either side of a door, when said door is in the closed position. The assembly includes a knob arrangement having mounting means which includes a bearing sleeve that is threadably engaged with a mounting plate affixed to the door. Rotation of said bearing sleeve is precluded by an apertured escutcheon plate through which said bearing sleeve is engaged. The bearing sleeve and escutcheon aperture have complementary flats or non-round surfaces such that when the escutcheon is in place rotation of the bearing sleeve is precluded. Further, the escutcheon plate is held in place by holding means that can only be released when the door is opened. In the disclosed embodiment the holding means is a key cylinder engaged through a second aperture in the escutcheon plate and fixed in place by a set screw mounted in the edge face of the door.

Abstract: There is disclosed a door position monitoring assembly for a security door installation wherein the assembly can be adjusted and preset from the exterior of the assembly. In this regard, the monitoring assembly includes a base member with switching means carried by the base member and capable of being operated to attain a first condition and a second condition, each of which conditions can be detected by suitable circuit means. A control arm produces operation of the switching means and has one end thereof coupled for movement with said door and the other end piotally mounted to the base member.