US5229750A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fail-safe leak detector including independent and repetetive sensing means
Assignee: Individual
•
Filing: 1991-08-02
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Granted: 1993-07-20
•
Expires: 2011-08-02
Abstract
Abstract A fail-safe system for the detection of water leaks, and for the prevention of damage therefrom. In a home or building which includes a hot-water tank and a water tank for a toilet, e.g., the damage-prevention system comprises valves for shutting off the supply of water to the tanks, and other valves for draining the tanks through discharge lines to the outside of the home or building. At the same time, power to the hot-water tank is shut off. A fail-safe water detector comprises a float with a metal cap, a first pair of electrical probes below the float, and a second pair of electrical probes above the metal cap and separated from the cap by an air gap. A circuit is closed in any of three ways: (1) when water contacts the first pair of probes, (2) when water raises the float and makes contact between the metal cap and the second pair of probes, and (3) when water contacts the second pair of probes.
Inventors
- 👤 James G. Welch, Jr.
- 👤 James W. Simmons
- 👤 Demetrius Vassiliou
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 04:54
CPC Classifications
G; G08; G08B; G08B21/00; G08B21/18; G08B21/20; G01; G01F; G01F23/00; G01F23/22; G01F23/24; G01F23/241; G01F23/242; G01F23/243; G01F23/30; G01F23/64; G01F23/68; G01F23/70; G01M; G01M3/00; G01M3/02; G01M3/04; G01M3/16; G01M3/18; G01M3/186; Y; Y10; Y10T; Y10T137/00; Y10T137/8158
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
259 words
A fail-safe electrical sensor for detecting a water leak, the sensor comprising: (a) a float having an electrically-conductive top; (b) means for signalling a closed electrical circuit; (c) a first pair of electrical conductors disposed below the float and electrically connected to a source of electricity; and (d) a second pair of electrical conductors disposed directly above and spaced apart from the float's conductive top, and electrically connected to the source of electricity; the first and second pairs of conductors being connected in parallel to the source of electricity, the individual conductors of each pair of electrical conductors being spaced apart from one another to provide an open circuit in the absence of the detection of a water lead, the distance separating the individual conductors of the second pair of conductors being less than the width of the electrically-conductive top of the float to provide an open circuit in the absence of the detection of a water leak; whereby (e) a first electrical contact is made by water contacting the first pair of electrical conductors, thereby closing a first circuit and producing a first signal; (f) a second electrical contact is made by rising water raising the float to a level at which electrical contact is made between the second pair of electrical conductors and the electrically-conductive top of the float, thereby closing a second circuit and producing a second signal; and (g) a third electrical contact is made by rising water contacting the second pair of electrical conductors, thereby closing the second circuit and producing the second signal.
Claim 2
Dependent Claim
259 words
A fail-safe electrical sensor for detecting a water leak, the sensor comprising: (a) a float having an electrically-conductive top; (b) means for signalling a closed electrical circuit; (c) a first pair of electrical conductors disposed below the float and electrically connected to a source of electricity; and (d) a second pair of electrical conductors disposed directly above and spaced apart from the float's conductive top, and electrically connected to the source of electricity; the first and second pairs of conductors being connected in parallel to the source of electricity, the individual conductors of each pair of electrical conductors being spaced apart from one another to provide an open circuit in the absence of the detection of a water lead, the distance separating the individual conductors of the second pair of conductors being less than the width of the electrically-conductive top of the float to provide an open circuit in the absence of the detection of a water leak; whereby (e) a first electrical contact is made by water contacting the first pair of electrical conductors, thereby closing a first circuit and producing a first signal; (f) a second electrical contact is made by rising water raising the float to a level at which electrical contact is made between the second pair of electrical conductors and the electrically-conductive top of the float, thereby closing a second circuit and producing a second signal; and (g) a third electrical contact is made by rising water contacting the second pair of electrical conductors, thereby closing the second circuit and producing the second signal.
Claim 3
Independent Claim
176 words
A device for detecting a water leak, the device comprising: (a) a float having an electrically-conductive top; (b) a first pair of electrical conductors disposed below the float; and (c) a second pair of electrical conductors disposed directly above and spaced apart from the float's conductive top; the individual conductors of each pair of conductors being spaced apart from one another to form an open circuit in the absence of the detection of a water leak, the distance separating the individual conductors of the second pair of conductors being less than the width of the conductive top of the float, to provide an open circuit in the absence of a water leak, whereby a first electrical circuit is closed by water contacting the first pair of conductors, a second electrical circuit is closed by rising water raising the float to a level at which electrical contact is made between the second pair of conductors and the conductive top of the float, and the second electrical is closed by rising water contacting the second pair of conductors.
Claim 4
Independent Claim
176 words
A device for detecting a water leak, the device comprising: (a) a float having an electrically-conductive top; (b) a first pair of electrical conductors disposed below the float; and (c) a second pair of electrical conductors disposed directly above and spaced apart from the float's conductive top; the individual conductors of each pair of conductors being spaced apart from one another to form an open circuit in the absence of the detection of a water leak, the distance separating the individual conductors of the second pair of conductors being less than the width of the conductive top of the float, to provide an open circuit in the absence of a water leak, whereby a first electrical circuit is closed by water contacting the first pair of conductors, a second electrical circuit is closed by rising water raising the float to a level at which electrical contact is made between the second pair of conductors and the conductive top of the float, and the second electrical is closed by rising water contacting the second pair of conductors.
References Cited (Backward Citations)
US1912798A
Cited
GB915777A
Cited
US3200388A
Cited
US4136823A
Cited
US4246575A
Cited
US4374379A
Cited
US4490715A
Cited
US4488567A
Cited
US4630038A
Cited
US4677371A
Cited
US4745399A
Cited
FR2601453A1
Cited
US4845472A
Cited
GB2202358A
Cited
US4788529A
Cited
US4916437A
Cited
US4819551A
Cited
US4805662A
Cited
US4973947A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1996-07-19 | 1997-01-18 | 1997-07-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-07-19 | 2001-01-18 | 2001-07-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-07-19 | 2005-01-18 | 2005-07-20 | $7700.00 | Window Closed / Lapsed |