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US3892976A Expired / Lapsed US ⏱️ 0.0 years remaining

Auto theft prevention device

Assignee: Individual
•
Filing: 1974-05-20
•
Granted: 1975-07-01
•
Expires: 1994-05-20
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Abstract

Abstract A security system for motor vehicle ignition or starting circuits wherein a lock switch unit is connected between essential circuit elements such as the primary coil and the distributor. The system has a special provision for the defeating attempts to bypass the lock switch by cutting the conductors to and from the switch and shorting the circuit between the essential circuit elements. This is accomplished by means of a cable extending between the lock switch unit and an essential circuit element and comprising a plurality (e.g., 20 or more) of discrete identical insulated conductors. A first group of these conductors is connected between the switch unit and one essential circuit element, a second group between the switch unit and another essential circuit element and a third group is grounded at one end. If the cable is cut through by a thief, he would be unable to distinguish the conductors of the three groups and would thus be frustrated in an attempt to bypass or short circuit the lock switch.

Inventors

  • 👤 Theodore L Tsevdos
  • 👤 Nicholas L Tsevdos
  • 👤 Milton D Tenenbaum

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-30 19:01
CPC Classifications
B; B60; B60R; B60R25/00; B60R25/01; B60R25/04

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 95 words
In a security system for a motor vehicle electrical circuit including a lock switch assembly electrically connected between two essential circuit elements of said circuit, the improvement which comprises a cable consisting of a plurality of discrete identical insulated conductors including a first group connected between one of said essential circuit elements and said lock switch, a second group connected between the other of said essential circuit elements and said lock switch, and a third group connected to ground whereby if said cable is cut the conductors of said groups are indistinguishable from one another.
Claim 2
Dependent Claim 95 words
In a security system for a motor vehicle electrical circuit including a lock switch assembly electrically connected between two essential circuit elements of said circuit, the improvement which comprises a cable consisting of a plurality of discrete identical insulated conductors including a first group connected between one of said essential circuit elements and said lock switch, a second group connected between the other of said essential circuit elements and said lock switch, and a third group connected to ground whereby if said cable is cut the conductors of said groups are indistinguishable from one another.
Claim 3
Dependent Claim 65 words
Apparatus as defined in claim 1 wherein said first and second groups comprises an equal number of conductors, wherein less than said number of conductors would have insufficient combined current carrying capacity to provide adequate current between said essential circuit elements to operate said engine, and wherein any attempt to complete a circuit with even one wire from the third group will ground the system.
Claim 4
Dependent Claim 26 words
Apparatus as defined in claim 2 wherein said first and second groups each comprises seven conductors and wherein said third group comprises at least seven conductors.
Claim 5
Dependent Claim 88 words
Apparatus as defined in claim 1 wherein said lock switch assembly is encased within a sealed housing defining an enclosed chamber, wherein said first and second groups of conductors are wrapped around the walls of said enclosed chamber at least one convolution, wherein said third group is bundled inside said housing making it impossible to put it out, and all of said conductors are embedded in an electrical potting compound so that any attempt to cut the housing will also cut such wires and make engine operation impossible.
Claim 6
Dependent Claim 22 words
Apparatus as defined in claim 1 wherein said essential circuit elements comprise the primary coil and distributor of the engine ignition circuit.
Claim 7
Dependent Claim 20 words
Apparatus as defined in claim 1 wherein said essential circuit elements comprise the engine starter and the actuating switch therefor.

References Cited (Backward Citations)

US2912600A Cited
US3340370A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1978-06-30 1978-12-30 1979-07-01 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1982-06-30 1982-12-30 1983-07-01 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1986-06-30 1986-12-30 1987-07-01 $7700.00 Window Closed / Lapsed

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