Alvin S Levenson1112 Guilford Ave, Baltimore, MD 21202

5771720, Jun 30, 1998

Mar 26, 1996

8/622006

Alvin S. Levenson - Baltimore MD

The Brooke - Duveen Group, Ltd. - Baltimore MD

E05C 1732

70 93

A system for locking a door can: (1) lock the door in dead bolt fashion in three modes, (2) allow the door to open a limited distance, or (3) allow the door to open freely. The system has a door-mounted latch assembly that includes a base plate, an intermediate link pivoted to the base plate, and a mode selection and latching assembly that is pivoted to the intermediate link. A latch plate is mounted on the door frame in juxtaposition to the door-mounted latch assembly. The latch plate has a tubular portion with an opening for receiving the latch member. A sleeve fits inside the tubular portion of the latch plate. When the latch member is engaged in the tubular portion of the latch plate, the sleeve can be rotated so that the latch member is engaged to the sleeve in a secured position. The latch plate includes a locking mechanism to releasably lock the sleeve into the secured position. The locking mechanism may be a spring-loaded pin mounted within the sleeve.

6145351, Nov 14, 2000

Jun 18, 1999

9/336876

Alvin S. Levenson - Upperco MD

The Brooke-Duveen Group, Ltd. - Baltimore MD

E05C 1732

70 93

A Z-bar security system, one which is provided with a key and a secured latch, is combined with an electronic alarm and monitoring system. This combination provides the maximum degree of both mechanical and electronic security. In a preferred embodiment, a Z-bar latch assembly has a three-position rotatable cylinder which is operable by a key from outside of the door. These three positions correspond, respectively, to "open", "viewing" and "closed" positions of the door.

6327878, Dec 11, 2001

Sep 3, 1999

9/389602

Alvin S. Levenson - Upperco MD

E05B 7300

70 14

A portable security device which can be easily mounted on inwardly swinging doors. the device is made up of a inner plate which has first and second panels, an outer plate which has first and second panels, a hinge connecting, and permitting rotation between, the second panel of the inner plate and the first panel of the outer plate, a securing attachment, and a holding mechanism. The first and second panels of the inner plate are perpendicular to each other. The first panel of the inner plate fits against the strike plate and has a lock tab which fits into the bolt hole in a strike plate. The second panel of the inner plate fits against side edge of the door jamb and contains a horizontal protrusion which contains an opening. The first panel of the outer plate contains a horizontal slot which will fit over the protrusion when the device is in place, thus exposing the opening of the protrusion. The second panel of the outer plate is perpendicular to the first panel.