Patent US1239005A successfully refreshed from Google Patents.
Patent US3971017A successfully refreshed from Google Patents.
US3971017A
Expired / Lapsed
US
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Method and apparatus for exciting the driving coils of audible warning devices
Assignee: PENELOPEGAY ROWLAND ABSALOM
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Filing: 1975-04-30
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Granted: 1976-07-20
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Expires: 1995-04-30
Abstract
Abstract Although audible devices such as warning devices have been operated from A.C. mains supplies the associated electrical and/or electronic circuitry has been bulky. The invention provides low bulk arrangement comprising first and second capacitor means, the effective capacitance of the two means being in series for connection across an alternating current mains supply, said second capacitor means having connected across it a rectifier and also the series combination of an electronic voltage sensitive switch and the operating means of the warning device, the arrangement being such that, in operation, the charge on the second capacitor means is periodically discharged through said operating means.
Inventors
- 👤 Henry Sutcliffe
- 👤 Edward Ball
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 11:51
CPC Classifications
G; G08; G08B; G08B3/00; G08B3/10
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
83 words
A circuit arrangement means for exciting an audible device, comprising first and second capacitor means, the effective capacitance of the two means being in series for connection across an alternating current mains supply, said second capacitor means having connected across it a rectifier and also the series combination of an electronic voltage sensitive switch and the operaing means of the warning device, the arrangement being such that, in operation, the charge on the second capacitor means is periodically discharged through said operating means.
Claim 2
Dependent Claim
83 words
A circuit arrangement means for exciting an audible device, comprising first and second capacitor means, the effective capacitance of the two means being in series for connection across an alternating current mains supply, said second capacitor means having connected across it a rectifier and also the series combination of an electronic voltage sensitive switch and the operaing means of the warning device, the arrangement being such that, in operation, the charge on the second capacitor means is periodically discharged through said operating means.
Claim 3
Dependent Claim
26 words
A circuit arrangement means as claimed in claim 1 wherein the first capacitor means has a smaller capacitance value than that of the second capacitance means.
Claim 4
Dependent Claim
33 words
A circuit arrangement means as claimed in claim 2, wherein the second capacitor means is an electrolytic type capacitor and the rectifier is poled to prevent adverse reverse voltages from being developed thereacross.
Claim 5
Dependent Claim
36 words
A circuit arrangement means as claimed in claim 1, wherein the electronic switch comprises a complementary pair of cross-coupled bipolar transistors arranged to become conductive when the voltage across the switch reached a predetermined threshold value.
Claim 6
Dependent Claim
37 words
A circuit arrangement means as claimed in claim 1, wherein the electronic switch comprises a silicon controlled rectifier circuit in which the gate electrode is connected to the intermediate point of a potentiometer connected across the rectifier.
References Cited (Backward Citations)
US3569963A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-07-20 | 1980-01-19 | 1980-07-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-07-20 | 1984-01-19 | 1984-07-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-07-20 | 1988-01-19 | 1988-07-20 | $7700.00 | Window Closed / Lapsed |