Vibration sensor for boundary fences

• US 20060022821A1
• Filed: 06/16/2005
• Published: 02/02/2006
• Est. Priority Date: 08/02/2004
• Status: Active Grant

• Current Assignee: Asaf Gitelis
• Original Assignee: Asaf Gitelis
• Inventors: Gitelis, Asaf
• Granted Patent: US 7,532,118 B2
• Time in Patent Office: Days
• US Class Current: 340/566
• CPC Class Codes: G08B 13/122 for a perimeter fence features peculiar to electrified fences A01K3/00

Abstract

It is an aim of the preferred embodiment, to provide an improved sensor unit that is at least as reliable as two sensor units of the prior art, thereby allowing one unit per fencing unit, i.e. per stretch of fencing between adjacent support posts to provide long term reliability.

Claims

1. A vibration sensor unit comprising a sensor housing consisting of an essentially hemispherical top section and an essentially hemispherical bottom section fastened together by fasteners and having a channel therethrough, through which a signal cable may be run;

the sensor housing being supported by a back plate having a concave socket thereon that engages the essentially spherical housing, allowing accurate positioning of sensors therein, with respect to the horizontal;

the essentially spherical housing being held against the socket by a clasp that encircles the sensor housing therearound, and being attached to the back plate by fixing means;

the back plate including attaching means for attaching it to an installation, wherein the sensor unit comprises six sensors connected in parallel, each sensor comprising a conductive ball supported on electrical contacts.

2. The vibrating sensor unit of claim 1, wherein said electrical contacts supporting each sensor ball are three legs arranged in an equilateral triangle configuration.

3. The vibrating sensor unit of claim 2, wherein each said leg comprises a miniature sphere supported in a cup on a leg shaped like a miniature golf tee.

4. The vibrating sensor unit of claim 1, wherein said electrical contacts are a pair concentric rings, the six sensor balls each contacting both concentric rings.

5. The vibrating sensor unit of claim 1, wherein the six sensors are arranged in a hexagon arrangement.

6. The vibrating sensor unit of claim 1, wherein the attaching means is a second plate, such that when installation is a section of wire fencing, a portion of the wire fencing is sandwiched between the back plate and second plate, perhaps using the fixing means.

7. The vibrating sensor unit of claim 1, wherein the six sensors are connected in parallel by being mounted on a printed circuit board having two rings of contacts.

8. The vibrating sensor unit of claim 1, further comprising a resistor in series with the sensors, providing a significant electrical resistance to sensor unit as a safeguard against being undetectably shorted out.

9. The vibrating sensor unit of claim 1, wherein there is provided an improved drainage hole in the lowest point of the bottom hemispherical piece, the improvement being that the drainage hole is mounted within a shallow slot thereby preventing it being blocked by the clamp therearound.

10. The vibrating sensor unit of claim 1, wherein a blind hole comprising a tube having an opening in the top end thereof, and a closed bottom end, is provided in center of the essentially hemispherical top section at highest point thereof, enabling the fixing of a pin therein, thereby enabling the sensor unit to be mounted upside down in the socket of a horizontally mounted back plate, via a hole for head of said pin, facilitating substantially wear free transportation thereby.

11. The vibrating sensor unit of claim 1, having vertical spikes mounted thereon to deter perching birds.

13. A system for giving warning of infiltration of a security fence, by detecting vibrations of said fence, comprising a series of sensor units as claimed in claim 1, connected via a cable to a processing means and alarm means.

14. The system of claim 13 wherein each section of fencing between adjacent support posts has only one sensor thereon.

12. A vibration sensor comprising a conductive ball supported on three electrical contact supports arranged in an equilateral triangle arrangement, wherein each contact support comprising a miniature sphere supported in a cup on a leg, such that the cup on the leg resembles a miniature golf tee.