Screen for burglar alarms and method of making the same

• US 4,999,608 A
• Filed: 07/19/1989
• Issued: 03/12/1991
• Est. Priority Date: 07/19/1989
• Status: Expired due to Fees

• Current Assignee: Sentry Alarm Screens, Ltd.
• Original Assignee: David E. Galomb
• Inventors: Galomb, David E.
• Primary Examiner(s): Swann, III, Glen R.
• Application Number:
  US07/381,961
• Time in Patent Office: 601 Days
• Field of Search: 340/550, 340/547
• US Class Current: 340/550
• CPC Class Codes: G08B 13/126 for a housing, e.g. a box, a safe, or a room

Abstract

An electrically conductive security screen includes an electrical resistance sensor and alarm to detect tampering with the screening material of a window. An elongated path of flexible and electrically conductive coating composition is applied to the screening material in a predetermined and non-overlapping pattern, such that a closed circuit loop is formed when it is attached to the sensor alarm; the coating having an electrical resistance that varies when it is distorted or its path interrupted. The pattern having a marginal section of high electrical resistance and being in series with at least one switch.

Claims

1. In an electrically conductive security screen apparatus for use in a window frame and cooperating with a closed-circuit intrusion alarm system including an electrical-resistance-sensing means and alarm means to detect tampering with the screening material of a window screen apparatus, said window screen apparatus including a frame defining a window aperture, screening material comprising a non-conductive mesh of interwoven strands covering the window aperture, and flexible retaining means for securing the outer periphery of the screening material to the inner periphery of the screen frame, an improvement comprising;

An electrically conductive coating composition applied to the screening material in a predetermined non-overlapping pattern of electrical continuity, the pattern having a first end and a second end, such that a closed-circuit loop is formed when it is connected in series to said electrical-resistance-sensing means, the pattern having an electrical resistance that varies if it si distorted or its path interrupted.

2. The improvement of claim 1, wherein a connector means removably interconnects the security screen apparatus to the electrical-resistance-sensing means.

3. The improvement of claim 1, wherein the electrically conductive coating composition is pigmented.

4. The improvement of claim 1, wherein the electrically conductive coating composition is substantially translucent.

5. The improvement of claim 1, wherein a section of the conductive pattern is of measurably greater electrical resistance.

6. The improvement of claim 1, wherein the screening material is overcoated to electrically insulate and improve the weatherability of the conductive pattern.

7. The improvement of claim 1, wherein the screening material is overcoated to conceal the conductive pattern.

8. The improvement of claim 1, wherein the conductive pattern is in electrical series with at least one switch in the screen frame.

9. A method of making a window screen security device apparatus, said window screen apparatus including a screen frame defining a window aperture, screening material comprising a mesh of interwoven non-conductive strands covering the window aperture, and flexible retaining means for securing the outer periphery of the screening material to the inner periphery of the screen frame, an improvement comprising;

The application of an elongated path of flexible and electrically conductive coating composition to the screening material creating a predetermined non-overlapping pattern of electrical continuity, the pattern having a first end and a second end, such that a closed-circuit loop is formed when it is connected electrical series to an electrical-resistance-sensing means, the pattern having an electrical resistance that varies if it is distorted or its path interrupted.

10. The improvement of claim 9, wherein a connector means is used to removably interconnect the conductive coating pattern to the sensing means.

11. The improvement of claim 9, wherein the electrically conductive coating composition is pigmented.

12. The improvement of claim 9, wherein the electrically conductive coating composition is substantially translucent.

13. The improvement of claim 9, wherein a section of the conductive coating path is substituted with a flexible and electrically conductive coating composition of measure ably greater electrical resistance.

14. The improvement of claim 9, wherein an overcoating is applied to the screening material to electrically insulate and improve the weatherability of the conductive coating pattern.

15. The improvement of claim 9, wherein an overcoating is applied to the screening material to conceal the conductive coating pattern.

16. The improvement of claim 9, wherein at least one switch in the screen frame is placed in electrical series with the conductive coating pattern.

17. An electrically conductive security screen, for use with a normally-closed-circuit electrical-resistance-sensing alarm device, including screening material comprising a mesh of interwoven non-conductive strands to be disposed about the area to be protected, an improvement comprising;

An electrically conductive coating composition applied to the screening material in a predetermined non-overlapping pattern of electrical continuity, having a first end and having a second end, such that a closed-circuit loop is formed when it is connected in series to said electrical-resistance-sensing alarm, the said pattern having an electrical resistance that varies if it is distorted or its path interrupted.

18. The improvement of claim 17, wherein the security screen removably interconnects with the sensing alarm means.

19. The improvement of claim 17, wherein the electrically conductive coating composition is pigmented.

20. The improvement of claim 17, wherein the electrically conductive coating composition is substantially translucent.

21. The improvement of claim 17, wherein a section of the conductive coating pattern is of measurably greater electrical resistance.

22. The improvement of claim 17, wherein the screening material is overcoated to electrically insulate and improve the weatherability of the conductive coating pattern.

23. The improvement of claim 17, wherein the screening material is overcoated to conceal the conductive coating pattern.

24. The improvement of claim 17, wherein at least one switch is in electrical series with the conductive coating pattern.