ELECTRIC ALARM SCREEN

• US 3,696,373 A
• Filed: 08/12/1970
• Issued: 10/03/1972
• Est. Priority Date: 08/12/1970
• Status: Expired due to Term

• Current Assignee: George Kenneth Hornbrook, John Malcolm Dunn
• Original Assignee: George Kenneth Hornbrook, John Malcolm Dunn
• Inventors: Dunn, John Malcolm, Hornbrook, George Kenneth
• Primary Examiner(s): Habecker, Thomas B.
• Assistant Examiner(s): Partridge, Scott F.
• Application Number:
  US05/063,127
• Time in Patent Office: 783 Days
• Field of Search: 340/273,274,276 200/52D
• US Class Current: 52/664
• CPC Class Codes: G08B 13/126 for a housing, e.g. a box, a safe, or a room

Abstract

A screen with mesh wires of one extension of conductive material electrically separates from screen wires of the opposite extension which may be conductive or nonconductive, is held in a frame having side members each having troughs to receive and hold the wires or strands. Two sets of wire connectors in one trough and one set of wire connectors in an opposite trough establish runs spaced transversely to the conductive strands across the screen mesh. A connector from each set in a trough is next adjacent a connector from the other set. One continuous electrical path back and forth across the screen mesh is established, as are parallel discontinuous paths intermediate the spaced runs of the continuous path. Leads from the screen frame conventional join the connector sets into an alarm circuit including conventional open circuit and closed circuit detectors. The detectors are adapted to actuate an alarm-which may be audible, visual, or recording-when the screen is cut or shorted.

Claims

1. An alarm screen for use with electrical open circuit and closed circuit detectors linked to a perceivable alarm, the combination comprising side and end members defining a screen frame, means for securing the frame at an opening, a screen mesh receptor in the members of the screen frame, a screen mesh having conductive strands of one extension electrically separate from strands of oppOsite extension, a plurality of electrical connectors in each of two opposed screen frame members establishing a continuous electrical path back and forth across the screen mesh through the conductive strands, a continuous connector conductor on one of the two opposed screen members, connector elements spaced along the conductor and making electrical contact with transversely spaced conductive strands, and means electrically connecting the connectors and the continuous conductor to the detectors.

2. Apparatus in accordance with claim 1 wherein each strand of the screen mesh of one extension comprises a conductive wire, and wherein each strand of opposite extension comprises a nonconductive wire.

3. Apparatus in accordance with claim 1 wherein each strand of the screen mesh comprises a conductive wire, and an insulating sheath on the wire.

4. Apparatus in accordance with claim 3 wherein a second pair of opposed screen frame members carries on each frame member second plurality of electrical connectors establishing a continuous electrical path back and forth across the screen mesh through the conductive strands of opposite extension, a second continuous conductor on one of the two opposed screen frame members of the second pair, connector elements spaced along the conductor and making contact with transversely spaced conductive strands of the opposite extension, and means connecting the second connectors and the second conductor to the detectors.

5. An alarm screen for use with electrical open circuit and closed circuit detectors linked to a perceivable alarm, the combination comprising side and end members defining a screen frame, means for securing the screen frame to on opening, a screen mesh retaining trough in the members of the screen frame, screen mesh having conductive strands and nonconductive strands, a screen bead securing the screen mesh margins in the troughs of the screen frame members, a continuous conductor on one screen frame member electrically contacting a plurality of transversely spaced conductive strands;

a plurality of contactors on each of two opposed frame members each in contact with at least one conductive strand so as to establish a continuous electrical path back and forth across the screen mesh through the conductive strands, and means electrically connecting the conductor and the connectors to the detectors.

6. Apparatus in accordance with claim 5 wherein the screen bead carries the continuous conductor and the plurality of connectors.

7. Apparatus in accordance with claim 5 wherein the conductor strands of the screen mesh extend transversely to the nonconductor strands.

8. Apparatus in accordance with claim 5 wherein the screen bead, the continuous conductor and a plurality of spaced connectors bind the screen mesh margins to the frame members.

9. Apparatus in accordance with claim 5 wherein the means for securing the frame to the opening includes connector means linking the conductor to the closed circuit detector.

10. Apparatus in accordance with claim 5 wherein the means for securing the screen frame to the opening includes connector means linking the contactors to the open circuit detector.

11. Apparatus in accordance with claim 5 wherein the continuous conductor comprises conductive strip, contact fingers extending from the edge of the strip, and curved portions on said fingers conforming to the retaining trough and adapted to contact electrically the conductive strands of the screen mesh at the mesh margin.