US3889247A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Device for detecting the presence of liquids
Assignee: Individual
•
Filing: 1973-12-17
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Granted: 1975-06-10
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Expires: 1993-12-17
Abstract
Abstract A device for detecting the presence of liquid such as flood water, and for providing an audible alarm signal when such liquid is present. The device comprises a housing - which is preferably of generally spherical shape and capable of floating in a stable upright position. In the housing is provided an electro-acoustic transducer provided with a metal diaphragm. At least two mutually spaced electrodes are supported on an exterior surface portion of the housing to be exposed to contact by liquid to be detected. The device is provided with electrical circuit means including the electrodes and responsive to a change in impedence therebetween to generate a signal condition. The device also includes electrical generator means located in the housing and electrically connected to the circuit means to generate an electrical signal to operate the transducer in response to the signal condition generated when either electrically conductive or electrically non-conductive liquid contacts the electrodes.
Inventors
- 👤 Walter Voll
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 20:10
CPC Classifications
G; G01; G01F; G01F23/00; G01F23/30; G01F23/64; G01F23/68; G01F23/70; G01F23/22; G01F23/24; G01F23/241; G01F23/26; G01F23/263; G01F23/265
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
218 words
A detector device for detecting the presence of liquids, the device comprising in combination: a housing; electro-acoustic transducer means supported in said housing; at least two mutually spaced electrodes supported on an exterior surface portion of said housing to be exposed to contact by liquid to be detected; electrical circuit means including said electrodes and responsive to a change in impedence therebetween to generate a signal condition; electrical generator means in said housing and electrically connected to said circuit means to generate an electrical signal to operate said transducer in response to said signal condition, said generator means comprising a first pulse generator connected to said electrical circuit means, a second pulse generator, and a blocking oscillator having input means connected to output means of said second pulse generator, said first pulse generator generating a train of pulses of which the pulse repetition frequency is responsive to said signal condition, said pulse train being applied to input means of said second pulse generator to cause the latter to generate an electrical pulse to trigger said blocking oscillator and thereby to provide said electrical signal to operate said transducer when and only when said pulse repetition frequency is less than a predetermined value; whereby said transducer provides an audible indication of the presence of such liquid at said electrodes.
Claim 2
Dependent Claim
218 words
A detector device for detecting the presence of liquids, the device comprising in combination: a housing; electro-acoustic transducer means supported in said housing; at least two mutually spaced electrodes supported on an exterior surface portion of said housing to be exposed to contact by liquid to be detected; electrical circuit means including said electrodes and responsive to a change in impedence therebetween to generate a signal condition; electrical generator means in said housing and electrically connected to said circuit means to generate an electrical signal to operate said transducer in response to said signal condition, said generator means comprising a first pulse generator connected to said electrical circuit means, a second pulse generator, and a blocking oscillator having input means connected to output means of said second pulse generator, said first pulse generator generating a train of pulses of which the pulse repetition frequency is responsive to said signal condition, said pulse train being applied to input means of said second pulse generator to cause the latter to generate an electrical pulse to trigger said blocking oscillator and thereby to provide said electrical signal to operate said transducer when and only when said pulse repetition frequency is less than a predetermined value; whereby said transducer provides an audible indication of the presence of such liquid at said electrodes.
Claim 3
Dependent Claim
99 words
A device as defined in claim 1, wherein said transducer means comprises a core of magnetisable material, a movable member of magnetisable material mounted in close proximity to said core to define an air gap between said core and said movable member, a sheet metal diaphragm rigidly connected to said movable member and flexibly connected to said housing, a first electrical winding disposed on said core and connected to output means of said generator means, and a second electrical winding disposed on said core and connected to input means of said generator means to provide an electrical feedback signal.
Claim 4
Dependent Claim
19 words
A device as defined in claim 1, wherein said first pulse generator comprises two transistors of mutually complementary type.
Claim 5
Dependent Claim
19 words
A device as defined in claim 1, wherein said second pulse generator comprises two transistors of mutually complementary type.
Claim 6
Dependent Claim
15 words
A device as defined in claim 1, wherein said housing comprises a hollow oblate spheroid.
Claim 7
Dependent Claim
59 words
A device as defined in claim 1, wherein said device is adapted to float in said liquid, and wherein the center of gravity of said device is located below the center of buoyancy of said device when the latter is afloat, whereby the device is capable of being maintained in a stable upright position when floating in said liquid.
Claim 8
Dependent Claim
26 words
A device as defined in claim 1, wherein each said electrode comprises a strip of electrically conductive material disposed on said outer surface of said housing.
Claim 9
Dependent Claim
27 words
A device as defined in claim 1, wherein each said electrode comprises a strip of electrically conductive material inlaid in an outer surface portion of said housing.
Claim 10
Dependent Claim
79 words
A device as defined in claim 1, wherein said housing comprises an elongate member having an end portion adapted to project into the interior of a container for said liquid, said electrodes being provided on said end portion of said elongate member and being electrically connected to said electrical circuit means, whereby said device is responsive to said liquid in said container being raised to such a level that said liquid contacts said electrodes to provide said audible indication.
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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) | 1978-06-09 | 1978-12-09 | 1979-06-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-09 | 1982-12-09 | 1983-06-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-09 | 1986-12-09 | 1987-06-10 | $7700.00 | Window Closed / Lapsed |