US3890612A
Expired / Lapsed
US
⏱️ 0.0 years remaining
High output audible alarm device utilizing a piezoelectric transducer
Assignee: Duracell Inc USA
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Filing: 1973-09-28
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Granted: 1975-06-17
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Expires: 1993-09-28
Abstract
Abstract An audible alarm device comprises solid-state amplifier drive circuit cooperating with a piezoelectric transducer to convert electrical energy into sound energy. An acoustical loading means, such as a horn, effectively transmits the sound to the air.
Inventors
- 👤 Louis P Sweany
- 👤 James D Pirtle
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 11:05
CPC Classifications
B; B06; B06B; B06B1/00; B06B1/02; B06B1/0207; B06B1/0223; G; G08; G08B; G08B3/00; G08B3/10; B06B2201/00; B06B2201/40; B06B2201/50; B06B2201/55
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
241 words
An audible alarm device comprising: a. an acoustical loading means; b. a piezoelectric transducer in spaced relation to said acoustical loading means; c. a solid-state amplifier drive circuit cooperating with said piezoelectric transducer to produce an audible signal including an activation circuit connected to said piezoelectric transducer, a voltage regulator connected to said activation circuit, and a power supply connection means connected to said voltage regulator, said activation circuit comprising: a transformer coil to increase voltage from a power supply to said piezoelectric transducer, a first NPN transistor, emitter connected to said voltage regulator and to a first side of a first resistance means, base connected to a first side of a second resistance means, to a first side of a third resistance means and also to a first side of a first capacitance means, collector connected to a second side of said first capacitance means and also to a primary winding of said transformer coil; a second side of said third resistance means connected to said voltage regulator, to a first side of a second capacitance means and also to a tap on said transformer coil; a secondary winding of said transformer coil connected to a second side of said second capacitance means and also to a first terminal of a piezoelectric transducer; a second side of said first resistance means connected to a second side of said resistance means and also to a second terminal of said piezoelectric transducer.
Claim 2
Dependent Claim
241 words
An audible alarm device comprising: a. an acoustical loading means; b. a piezoelectric transducer in spaced relation to said acoustical loading means; c. a solid-state amplifier drive circuit cooperating with said piezoelectric transducer to produce an audible signal including an activation circuit connected to said piezoelectric transducer, a voltage regulator connected to said activation circuit, and a power supply connection means connected to said voltage regulator, said activation circuit comprising: a transformer coil to increase voltage from a power supply to said piezoelectric transducer, a first NPN transistor, emitter connected to said voltage regulator and to a first side of a first resistance means, base connected to a first side of a second resistance means, to a first side of a third resistance means and also to a first side of a first capacitance means, collector connected to a second side of said first capacitance means and also to a primary winding of said transformer coil; a second side of said third resistance means connected to said voltage regulator, to a first side of a second capacitance means and also to a tap on said transformer coil; a secondary winding of said transformer coil connected to a second side of said second capacitance means and also to a first terminal of a piezoelectric transducer; a second side of said first resistance means connected to a second side of said resistance means and also to a second terminal of said piezoelectric transducer.
Claim 3
Dependent Claim
104 words
The audible alarm device according to claim 1 wherein said voltage regulator comprises a second NPN transistor, emitter connected to said activation circuit and to one side of a filter capacitor, base connected to a first side of a fourth resistance means and To the cathode of a zener diode, collector connected to a second side of said fourth resistance means and also to a power terminal of a power supply connection means; a second side of said filter capacitor connected to a second power terminal of said power supply connection means, to the anode of said zener diode and to said activation circuit.
Claim 4
Dependent Claim
26 words
The audible alarm device according to claim 1 wherein said power supply connection means comprises two lead wires capable of being connected to said power supply.
Claim 5
Dependent Claim
17 words
The audible alarm device according to claim 2 wherein each of said resistance means comprises a resistor.
Claim 6
Dependent Claim
17 words
The audible alarm device according to claim 2 wherein each of said capacitance means comprises a capacitor.
Claim 7
Dependent Claim
16 words
The audible alarm device according to claim 1 wherein said acoustical loading means comprises a horn.
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) | 1978-06-16 | 1978-12-16 | 1979-06-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-16 | 1982-12-16 | 1983-06-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-16 | 1986-12-16 | 1987-06-17 | $7700.00 | Window Closed / Lapsed |