US4819125A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Overcurrent detector
Assignee: Mitsubishi Electric Corp
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Filing: 1987-07-27
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Granted: 1989-04-04
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Expires: 2007-07-27
Abstract
Abstract A circuit breaker has a phase selecting circuit for selecting one phase among plural phases, in which the largest current flows. After selecting the largest phase, the judgement whether an accidental overcurrent flows or not in executed by using only output signals from the selected largest phase.
Inventors
- 👤 Ichirou Arinobu
- 👤 Yoshihiro Hatakeyama
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 07:59
CPC Classifications
H; H02; H02H; H02H3/00; H02H3/08; H02H3/083; H02H3/093; H02H3/0935
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
162 words
A circuit breaker for a multiple phase A.C. power line comprising: at least one disconnectable contact means provided in said A.C. power line, current sensor means for respective phases of said A.C. power line for detecting a value of current flowing therein, secondary output signal generating means for generating secondary output signals corresponding to the current value of said respective phases sensed by said current sensor means, phase selecting means for selecting and outputting the largest among said secondary output signals corresponding to the respective current value of the selected phase of said current sensor means and making said selection by using a predetermined operating characteristic corresponding to a selected threshold value, signal conversion means for obtaining a mean or effective value of the selected and outputted secondary output signal of said phase selecting means, and processing means for processing an output signal of said signal conversion means to generate a release signal for disconnecting said contact means in said power line.
Claim 2
Dependent Claim
162 words
A circuit breaker for a multiple phase A.C. power line comprising: at least one disconnectable contact means provided in said A.C. power line, current sensor means for respective phases of said A.C. power line for detecting a value of current flowing therein, secondary output signal generating means for generating secondary output signals corresponding to the current value of said respective phases sensed by said current sensor means, phase selecting means for selecting and outputting the largest among said secondary output signals corresponding to the respective current value of the selected phase of said current sensor means and making said selection by using a predetermined operating characteristic corresponding to a selected threshold value, signal conversion means for obtaining a mean or effective value of the selected and outputted secondary output signal of said phase selecting means, and processing means for processing an output signal of said signal conversion means to generate a release signal for disconnecting said contact means in said power line.
Claim 3
Dependent Claim
18 words
A circuit breaker in accordance with claim 1, wherein said current sensor means comprises direct current transforming means.
Claim 4
Dependent Claim
32 words
A circuit breaker in accordance with claim 1, wherein said processing means provides plural outputs by AND logic and said release signal is provided by said AND logic of said plural outputs.
Claim 5
Dependent Claim
23 words
A circuit breaker in accordance with claim 3, wherein said plural outputs of said processing means are provided by mutually supplemental semiconductor means.
Claim 6
Dependent Claim
39 words
A circuit breaker in accordance with claim 1, wherein said current sensor means includes at least one first burden circuit for each secondary output signal and a second burden circuit which is serially connected to said first burden circuits.
Claim 7
Dependent Claim
28 words
A circuit breaker in accordance with claim 5, wherein said current sensor means includes a level shifting means for shifting a base potential of said first burden circuits.
Claim 8
Dependent Claim
19 words
A circuit breaker in accordance with claim 5, wherein said second burden circuit serves as an electric power source.
Claim 9
Dependent Claim
24 words
A circuit breaker in accordance with claim 5, wherein said first burden circuits are connected to a positive terminal of said second burden circuit.
Claim 10
Dependent Claim
24 words
A circuit breaker in accordance with claim 5, wherein said first burden circuits are connected to a negative terminal of said second burden circuit.
Claim 11
Dependent Claim
17 words
A circuit breaker in accordance with claim 6, wherein said level shifting means is a differential amplifier.
Claim 12
Dependent Claim
18 words
A circuit breaker in accordance with claim 6, wherein said level shifting means is a current mirror circuit.
Claim 13
Dependent Claim
138 words
An overcurrent detector for a multiphase A.C. power line comprising: current sensor means for respective phases of said A.C. power line for detecting a value of current flowing therein, secondary output signal generating means for generating secondary output signals corresponding to the current value of said respective phases sensed by said current sensor means, phase selecting means for selecting and outputting the largest among said second output signals corresponding to the respective current value of the respective phase of said current sensor means and making said selection by using a predetermined operating characteristic corresponding to a selected threshold value, signal conversion means for obtaining a mean or effective value of the selected-outputted secondary output signal of said phase generating means, and processing means for processing an output signal of said signal conversion means to generate a release signal.
Claim 14
Dependent Claim
138 words
An overcurrent detector for a multiphase A.C. power line comprising: current sensor means for respective phases of said A.C. power line for detecting a value of current flowing therein, secondary output signal generating means for generating secondary output signals corresponding to the current value of said respective phases sensed by said current sensor means, phase selecting means for selecting and outputting the largest among said second output signals corresponding to the respective current value of the respective phase of said current sensor means and making said selection by using a predetermined operating characteristic corresponding to a selected threshold value, signal conversion means for obtaining a mean or effective value of the selected-outputted secondary output signal of said phase generating means, and processing means for processing an output signal of said signal conversion means to generate a release signal.
Claim 15
Dependent Claim
18 words
An overcurrent detector in accordance with claim 12, wherein said current sensor means comprises direct current transforming means.
Claim 16
Dependent Claim
32 words
An overcurrent detector in accordance with claim 12, wherein said processing means provides plural outputs by AND logic and said release signal is provided by said AND logic of said plural outputs.
Claim 17
Dependent Claim
22 words
An overcurrent detector in accordance with claim 14, wherein said plural outputs of said processing means are provided mutually supplemental semiconductor means.
Claim 18
Dependent Claim
39 words
An overcurrent detector in accordance with claim 12, wherein said current sensor means includes at least one first burden circuit for each secondary output signal and a second burden circuit which is serially connected to said first burden circuits.
Claim 19
Dependent Claim
28 words
An overcurrent detector in accordance with claim 16, wherein said current sensor means includes a level shifting means for shifting a base potential of said first burden circuits.
Claim 20
Dependent Claim
19 words
An overcurrent detector in accordance with claim 16, wherein said second burden circuit serves as an electric power source.
Claim 21
Dependent Claim
24 words
An overcurrent detector in accordance with claim 16, wherein said first burden circuits are connected to a positive terminal of said second burden circuit.
Claim 22
Dependent Claim
24 words
An overcurrent detector in accordance with claim 16, wherein said first burden circuits are connected to a negative terminal of said second burden circuit.
Claim 23
Dependent Claim
17 words
An overcurrent detector in accordance with claim 17, wherein said level shifting means is a differential amplifier.
Claim 24
Dependent Claim
18 words
An overcurrent detector in accordance with claim 17, wherein said level shifting means is a current mirror circuit.
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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) | 1992-04-03 | 1992-10-03 | 1993-04-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-04-03 | 1996-10-03 | 1997-04-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-04-03 | 2000-10-03 | 2001-04-04 | $7700.00 | Window Closed / Lapsed |