Patent ID: 6145351
Filing Date: 2000-11-14
Classification: E05B,E05C,Y10T

Abstract:
In combination with a system to secure a latch member of a Z-Bar door latch system to a latch plate, wherein the Z-Bar door latch system provides (1) entry, (2) inspection, and (3) dead bolt modes of operation, and wherein the system to secure the latch member comprises:a latch plate for mounting on a door frame;a Z-Bar latch assembly for mounting onto an interior side of a door, the Z-Bar latch assembly including (1) a base plate for securing to an edge of said door, (2) an intermediate link pivotally connected to said base plate, and (3) a mode selection and latching assembly pivotally mounted to said intermediate link, said Z-Bar latch assembly further comprising a latch member;said latch plate comprising a tube having a tube opening for receiving said latch member;a sleeve having an opening, said sleeve being rotatably positioned inside of said tube of said latch plate;a handle affixed to one end of said sleeve for rotating said sleeve to engage said latch member inside said sleeve in a secure position;said latch plate further comprising a locking device which releasably locks said sleeve into said secure position, said locking device comprising a locking detent, a locking member, and a spring, said spring releasably holding said detent into engagement with said locking member in said secure position until said spring is compressed; anda latch assembly control mechanism to selectively lock and unlock said latch assembly from an exterior side of the door, said mechanism comprising a key-operated cylinder for mounting on said exterior of the door, a shaft connected at one end to said key-operated cylinder and a freely rotatable adapter connected to an opposite end of the shaft,wherein rotation of the handle in a first direction engages the sleeve in the secure position with the spring in the locking device urging the locking detent into engagement with the locking member such that the sleeve is prevented from rotating and movement of the latch member is prevented even with use of the key, andwherein rotation of the handle in an opposite second direction against the urging of the spring releases the engagement of the locking detent from the locking member such that the sleeve rotates and the key controls movement of the latch member such that the latch member may be disengaged from the sleeve;an electronic alarm system having at least one sensor, thereby providing the maximum degree of mechanical and electronic security.