Patent US3660666A successfully refreshed from Google Patents.
US3660666A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Radiation sensitive electronic time delay switch
Assignee: Individual
•
Filing: 1970-05-18
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Granted: 1972-05-02
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Expires: 1990-05-18
Abstract
Abstract The charge rate of a charging capacitor is controlled by the resistance of a photocell that is in turn controlled by the flashing rate of a flashing light, and the charge level of the charge capacitor energizes a uni-directional device that biases an SCR device to the ON condition closing a DC power circuit. The flashing rate of the flashing lamp is adjustable to establish a charge rate of the charge capacitor.
Inventors
- 👤 Alvin E Hendrickson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 14:10
CPC Classifications
H; H03; H03K; H03K3/00; H03K3/02; H03K3/35; H03K3/351; H03K3/42
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
123 words
An electronic time delay switch for closing a direct current electrical power circuit at a time subsequent to the time power is applied to said circuit comprising, an SCR device in series with the power circuit, a charge capacitor circuit having a charge capacitor, flasher light means energized by power being applied to the power circuit for flashing light at a given time rate, photoconductor means connected to said charge capacitor circuit and being illuminated by said flasher light means for conducting current to said charge capacitor at a charge rate proportioned to the time rate of the flashing light, and a uni-directional means for detecting a given level in said charge capacitor circuit for biasing said SCR device to the conducting condition.
Claim 2
Dependent Claim
123 words
An electronic time delay switch for closing a direct current electrical power circuit at a time subsequent to the time power is applied to said circuit comprising, an SCR device in series with the power circuit, a charge capacitor circuit having a charge capacitor, flasher light means energized by power being applied to the power circuit for flashing light at a given time rate, photoconductor means connected to said charge capacitor circuit and being illuminated by said flasher light means for conducting current to said charge capacitor at a charge rate proportioned to the time rate of the flashing light, and a uni-directional means for detecting a given level in said charge capacitor circuit for biasing said SCR device to the conducting condition.
Claim 3
Dependent Claim
22 words
An electronic time delay switch as claimed in claim 1 including, means for selectively adjusting the flashing rate of said flashing light.
Claim 4
Dependent Claim
25 words
An electronic time delay switch as claimed in claim 2 including, means in said charge capacitor circuit for adjusting the charge rate of said capacitor.
Claim 5
Dependent Claim
53 words
An electronic time delay switch as claimed in claim 1, in which, said flasher light means and said charge capacitor circuit, said SCR device and said uni-directional device are connected in parallel, and biasing means for said uni-directional device connected to the electrical connection between said flasher light means and said charge capacitor.
Claim 6
Dependent Claim
33 words
An electronic time delay switch as claimed in claim 4 including, a potentiometer connected in the electrical circuit between the connection of the biasing means for said uni-directional device and said photoconductor means.
Claim 7
Dependent Claim
33 words
An electronic time delay switch as claimed in claim 5 including, a potentiometer connected in series with said flashing light for being selectively adjusted to adjust the flashing rate of said flashing light.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-05-02 | 1975-11-01 | 1976-05-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-05-02 | 1979-11-01 | 1980-05-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-05-02 | 1983-11-01 | 1984-05-02 | $7700.00 | Window Closed / Lapsed |