US3569929A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Transient voltage detector burglar alarm system for vehicles
Assignee: Individual
•
Filing: 1968-04-19
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Granted: 1971-03-09
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Expires: 1988-04-19
Abstract
Abstract An alarm device to be connected across the battery of a motor vehicle to respond to transient voltage changes caused by electrical loading of the battery such as would be caused by energization of the vehicle door lights, brake light, or the like, and to thereby cause the vehicle horn to be energized. The device has an input circuit including the primary of a transformer. The secondary of the transformer is connected to the gate and cathode of a normally nonconducting silicon-controlled rectifier whose anode and cathode are connected in an energizing circuit containing the vehicle horn relay. The silicon-controlled rectifier is turned on in response to a transient voltage change detected by the transformer primary, thereby energizing the horn relay.
Inventors
- 👤 Gene S Wood
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 03:22
CPC Classifications
G; G08; G08B; G08B13/00; G08B13/22; B; B60; B60R; B60R25/00; B60R25/10; B60R25/1004
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
158 words
An alarm device for a motor vehicle having a battery comprising an electrical warning device, a normally nonconductive electronic switch device having a gate electrode, a cathode and an anode, an energizing circuit connecting the anode and cathode of said electronic switch device in circuit with said battery and warning device, voltage change-sensitive means, input circuit means connecting said voltage change-sensitive means across said battery including direct current blocking means having low alternating current impedance, said voltage change-sensitive means having output terminals including means to generate an output voltage across said output terminals responsive to a transient decrease in the terminal voltage of the battery caused by a sudden load on the battery and the internal resistance of the battery, and means connecting the output terminals of said voltage change-sensitive means across the gate electrode and the cathode of the electronic switch device to render the electronic switch device conducting responsive to said transient decrease in battery voltage.
Claim 2
Dependent Claim
158 words
An alarm device for a motor vehicle having a battery comprising an electrical warning device, a normally nonconductive electronic switch device having a gate electrode, a cathode and an anode, an energizing circuit connecting the anode and cathode of said electronic switch device in circuit with said battery and warning device, voltage change-sensitive means, input circuit means connecting said voltage change-sensitive means across said battery including direct current blocking means having low alternating current impedance, said voltage change-sensitive means having output terminals including means to generate an output voltage across said output terminals responsive to a transient decrease in the terminal voltage of the battery caused by a sudden load on the battery and the internal resistance of the battery, and means connecting the output terminals of said voltage change-sensitive means across the gate electrode and the cathode of the electronic switch device to render the electronic switch device conducting responsive to said transient decrease in battery voltage.
Claim 3
Dependent Claim
16 words
The alarm device of claim 1, and wherein said electronic switch device comprises a silicon-controlled rectifier.
Claim 4
Dependent Claim
24 words
The alarm device of claim 2, and wherein said voltage change-sensitive means includes a transformer having its primary included in said input circuit means.
Claim 5
Dependent Claim
22 words
The alarm device of claim 3, and wherein said direct current blocking means includes a capacitor connected in series with said primary.
Claim 6
Dependent Claim
16 words
The alarm device of claim 4, and means to substantially rectify the output of said transformer.
Claim 7
Dependent Claim
31 words
The alarm device of claim 5, and wherein said transformer has a secondary winding connected to said output terminals, and said rectifying means comprises a diode connected across the output terminals.
Claim 8
Dependent Claim
29 words
The alarm device of claim 6, and wherein said diode is polarized to substantially suppress voltage pulses on the gate electrode which are negative with respect to the cathode.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-03-08 | 1974-09-07 | 1975-03-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-03-08 | 1978-09-07 | 1979-03-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-03-08 | 1982-09-07 | 1983-03-09 | $7700.00 | Window Closed / Lapsed |