US4007713A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Test circuit
Assignee: C Cowles and Co
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Filing: 1975-08-28
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Granted: 1977-02-15
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Expires: 1995-08-28
Abstract
Abstract A test circuit for use with a boiler control circuit. A test switch and a lamp are connected between ground and a water level electrode. In the presence of a water path, a sufficient potential drop exists between ground and the electrode to light the lamp when the test switch is closed. If a ground or short exists, the lamp will not light.
Inventors
- 👤 Michael J. DeLeonardis
- 👤 Donado DeLeonardis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 03:26
CPC Classifications
H; H01; H01T; H01T13/00; H01T13/58; H01T13/60; F; F22; F22B; F22B37/00; F22B37/02; F22B37/42; F22B37/44; F22B37/443; F22B37/46; G; G01; G01R; G01R31/00; G01R31/28; G01R31/282; G01R31/2829
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
79 words
In a control circuit including a branch having a water path through which electrical current normally flows, the improvement for detecting a short circuit around said water path which comprises: a test switch having normally open first and normally closed second contacts, said normally closed second contacts being in series with said branch; a voltage indicator; and means connecting said normally open first contacts and voltage indicator in series across said water path to indicate a potential drop thereacross.
Claim 2
Dependent Claim
79 words
In a control circuit including a branch having a water path through which electrical current normally flows, the improvement for detecting a short circuit around said water path which comprises: a test switch having normally open first and normally closed second contacts, said normally closed second contacts being in series with said branch; a voltage indicator; and means connecting said normally open first contacts and voltage indicator in series across said water path to indicate a potential drop thereacross.
Claim 3
Dependent Claim
46 words
The improvement of claim 1 wherein said branch includes a heating element in series with said water path; said test switch includes normally open third contacts; and said connecting means includes a resistor connected in series with said normally open third contacts across said heating element.
Claim 4
Dependent Claim
12 words
The improvement of claim 1 wherein said voltage indicator is a lamp.
Claim 5
Dependent Claim
12 words
The improvement of claim 2 wherein said voltage indicator is a lamp.
Claim 6
Dependent Claim
249 words
A safety control system for actuating and deactuating a burner circuit for a boiler comprising, first and second electrical circuits and power supply means for said circuits; said first electrical circuit including a heat source, an initially closed switch, thermostat and aquastat means and switch in said first circuit responsive thereto, an electrode disposed in the boiler for completing said first circuit through a water path to the grounded wall of the boiler when the water level in the boiler is not below the electrode, and when the water level in the boiler falls below the electrode the heat source is deenergized and the consequent movement of the heat sensitive means causes reopening of an initially open switch of the second circuit and deactuation of said controlled circuit; said second electrical circuit including said initially open switch, means operative when said initially open switch of said second circuit is closed to actuate said control circuit, and heat sensitive means operative when both the switches of said first circuit are closed to close the initially open switch of said second circuit and, after a time interval, open the initially closed switch of the first circuit; and a test circuit comprising a test switch having normally open first and normally closed second contacts, said normally closed second contacts being in series with said water path, a voltage indicator, and means connecting said normally open first contacts and voltage indicator in series across said water path to indicate a potential drop thereacross.
Claim 7
Dependent Claim
249 words
A safety control system for actuating and deactuating a burner circuit for a boiler comprising, first and second electrical circuits and power supply means for said circuits; said first electrical circuit including a heat source, an initially closed switch, thermostat and aquastat means and switch in said first circuit responsive thereto, an electrode disposed in the boiler for completing said first circuit through a water path to the grounded wall of the boiler when the water level in the boiler is not below the electrode, and when the water level in the boiler falls below the electrode the heat source is deenergized and the consequent movement of the heat sensitive means causes reopening of an initially open switch of the second circuit and deactuation of said controlled circuit; said second electrical circuit including said initially open switch, means operative when said initially open switch of said second circuit is closed to actuate said control circuit, and heat sensitive means operative when both the switches of said first circuit are closed to close the initially open switch of said second circuit and, after a time interval, open the initially closed switch of the first circuit; and a test circuit comprising a test switch having normally open first and normally closed second contacts, said normally closed second contacts being in series with said water path, a voltage indicator, and means connecting said normally open first contacts and voltage indicator in series across said water path to indicate a potential drop thereacross.
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) | 1980-02-15 | 1980-08-16 | 1981-02-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-02-15 | 1984-08-16 | 1985-02-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-02-15 | 1988-08-16 | 1989-02-15 | $7700.00 | Window Closed / Lapsed |