← Back to Patent Explorer
US4297674A Expired / Lapsed US ⏱️ 0.0 years remaining

Passive security device

Assignee: JUBILEE Manufacturing Co
•
Filing: 1979-10-18
•
Granted: 1981-10-27
•
Expires: 1999-10-18
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract An antitheft device for a motor vehicle has a pushbutton disarming circuit coupled to a passive ignition cut-out circuit and to a passive arming circuit. The ignition cut-out circuit is interposed in the automobile ignition circuit and includes an SCR switchable from "on" to "off" by the disarming circuit to permit ignition. The passive arming circuit includes a Darlington amplifier configuration, is interposed in the automobile ignition circuit, and is coupled through an exit delay circuit to the remaining circuit portions of the device: interval timing and activating circuit, square-wave generator, trigger, entrace delay and siren circuits. The amplifier configuration supplies power to operate the circuits until switched by proper actuation of the disarming circuit and automobile ignition.

Inventors

  • 👤 Richard C. Merten

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-26 20:29
CPC Classifications
B; B60; B60R; B60R25/00; B60R25/01; B60R25/04; B60R25/045; B60R25/10; B60R25/1003; B60R25/1018

Claims Analysis

Total Claims: 12
Claim 1
Independent Claim 150 words
A passive security device, for use with vehicles having an electrical system including a starter, and an ignition switch having "on" and "accessory" contacts, said device comprising: first means for connecting said device to the electrical system; detection and alarm means including trigger means for detecting voltage variations and producing an electrical signal in response thereto, said trigger means being connected to said first means, generating means for converting said electrical signal into a square wave signal, said generating means being connected to said trigger means, siren means for sounding an alarm, and activating means connecting said generating means and said siren means and being responsive to said square wave signal to activate said siren means; first passive means for arming said detection and alarm means; second passive means for arming an ignition cut-out circuit; and disarming means connected between said first means and said first and second passive means.
Claim 2
Dependent Claim 150 words
A passive security device, for use with vehicles having an electrical system including a starter, and an ignition switch having "on" and "accessory" contacts, said device comprising: first means for connecting said device to the electrical system; detection and alarm means including trigger means for detecting voltage variations and producing an electrical signal in response thereto, said trigger means being connected to said first means, generating means for converting said electrical signal into a square wave signal, said generating means being connected to said trigger means, siren means for sounding an alarm, and activating means connecting said generating means and said siren means and being responsive to said square wave signal to activate said siren means; first passive means for arming said detection and alarm means; second passive means for arming an ignition cut-out circuit; and disarming means connected between said first means and said first and second passive means.
Claim 3
Dependent Claim 52 words
The passive security device of claim 1 and further wherein said first passive means includes paired transistor means having a base, an emitter and collectors, said base being connected to the electrical system, said emitter being connected to said disarming means, and said collectors being connected to said detection and alarm means.
Claim 4
Dependent Claim 22 words
The passive security device of claim 2 and further wherein said base is connected to the electrical system ignition switch "accessory" contact.
Claim 5
Dependent Claim 20 words
The passive security device of claim 2 or 3 and further wherein a filter means is connected to said base.
Claim 6
Dependent Claim 20 words
The passive security device of claim 2 or 3 and further wherein a filter means is connected to said collectors.
Claim 7
Dependent Claim 25 words
The passive security device of claim 2 or 3 and further wherein means for biasing said paired transistor means "off" is connected to said base.
Claim 8
Dependent Claim 181 words
The passive security device of claim 1 and further wherein said second passive means includes relay means connected to the electrical system, first switching means connected to said relay means and to said disarming means, and second switching means connected to said relay means, to said disarming means and to said first switching means; said relay means having an open and a closed position and being connected to a point between said ignition "on" contact and said starter, said first switching means having an "on" condition and an "off" condition, said second switching means having an "on" and an "off" condition; said first switching means permitting said relay means to move to said open position when said first switching means is in said "on" condition; said relay means permitting said second switching means to turn to said "on" condition when said relay means is in said closed position and said first switching means is in said "off" condition; said second switching means holding said first switching means in said "off" condition when said second switch is in said " on" condition.
Claim 9
Dependent Claim 34 words
The passive security device of claim 7 and further wherein said first switching means includes a silicon-controlled rectifier having a gate, said disarming means and said second switching means being connected to said gate.
Claim 10
Dependent Claim 55 words
The passive security device of claim 7 and further wherein said second switching means includes a transistor having a base, an emitter and a collector, said base being connected to a point between said relay means and said first switching means, said collector being connected to said disarming means and to said first switching means.
Claim 11
Dependent Claim 17 words
The passive security device of claim 9 and further wherein capacitor means is coupled to said base.
Claim 12
Dependent Claim 65 words
The passive security device of claims 1, 2 or 7 and further wherein said disarming means includes a normally closed switch having an open and a closed position, said switch permitting said device to automatically assume an armed condition when said switch is in said closed position; said switch being manually moveable to an open position to permit said device to assume a disarmed condition.

References Cited (Backward Citations)

US3585584A Cited
US3707702A Cited
US3829829A Cited
US3956732A Cited
US3930226A Cited
US4016537A Cited
US4107543A Cited
US4107543B1 Cited
US4174516A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1984-10-26 1985-04-27 1985-10-27 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1988-10-26 1989-04-27 1989-10-27 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1992-10-26 1993-04-27 1993-10-27 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag