Pressure actuated continuous switch

• US 4,060,705 A
• Filed: 04/07/1976
• Issued: 11/29/1977
• Est. Priority Date: 04/09/1975
• Status: Expired due to Term

• Current Assignee: Peachey Cyril John As Administrator of The Estate of Peachey Gwendoline NORA Deceased
• Original Assignee: Cyril John Peachey, Gwendoline Nora Peachey
• Inventors: Peachey, Cyril John
• Primary Examiner(s): Tolin, Gerald P.
• Application Number:
  US05/674,313
• Time in Patent Office: 601 Days
• Field of Search: 200/86 R, 200/86 A, 200/86.5, 200/61.19, 200/239, 200/153 C, 200/153 M, 200/153 S, 200/264, 200/275, 200/268, 200/278, 338/154, 340/272
• US Class Current: 200/512
• CPC Class Codes: H01B 7/106 comprising concentric conductors
• CPC Class Codes: H01H 3/142 of the elongated strip type

Abstract

A pressure actuated continuous switch in the form of a cable having two coaxial wires, which form the contacts of the switch, separated by a helically wound strip of insulating material. The pitch of the turns of the helical material determines the sensitivity of the switch. In a preferred form of the switch, a layer of semiconductive material is interposed between the insulating material and the other conductor.

Claims

1. A pressure actuated continuous switch comprising a central conductor, a filament of insulating material helically wound around the central conductor with empty spaces between the turns of said filament, a braided flexible tubular outer conductor coaxial with and surrounding the central conductor, and a flexible sheath of semiconductive material interposed between the insulating material and the outer conductor, whereby the conductors are normally insulated from one another by the helically wound filament of insulating material, and when pressure is applied to the assembly, the conductors are deformed into at least one of said empty spaces and are electrically connected through said flexible sheath.

2. A switch as claimed in claim 1 wherein the semi-conductive material is a graphite loaded plastic material.

3. A switch as claimed in claim 1 wherein the inner conductor is made of springy material.

4. A switch as claimed in claim 1 wherein the conductors are made of corrosion resistant material.

5. A switch as claimed in claim 1 wherein the two conductors are made of the same material.

6. A switch as claimed in claim 1 wherein the filament is made of elastic material.

7. A switch as claimed in claim 1 wherein the central conductor comprises a solid wire.

8. A switch as claimed in claim 1, wherein the outer conductor is covered externally by a sheath.

9. A switch as claimed in claim 8 wherein the sheath is made from plastics material.