US3959667A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Overcurrent trip device
Assignee: Allis Chalmers Corp
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Filing: 1974-03-07
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Granted: 1976-05-25
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Expires: 1994-03-07
Abstract
Abstract A signal voltage level sensing circuit particularly well adapted for use in a static overcurrent trip device. An operational amplifier is utilized to sense the difference between a signal voltage and a predetermined reference voltage while another operational amplifier is the memory element. Minimum duration of input signal to which the memory element responds is established by a resistor and a capacitor in conjunction with the threshhold of the memory element.
Inventors
- 👤 Donald R. Boyd
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 14:39
CPC Classifications
G; G01; G01R; G01R19/00; G01R19/165; G01R19/16566; G01R19/16571; H; H02; H02H; H02H3/00; H02H3/08; H02H3/093
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
103 words
In a signal voltage level sensing circuit; first means operable to sense the difference between a signal voltage and a predetermined reference voltage; a memory means operably connected to receive and store the output signal of said first means; a second means operably connected to said memory means and operable to increase the current and the voltage available from said memory means; means for controlling a minimum duration of input signal to which said memory means responds; and, means for preventing the magnitude of the voltages of said memory means from exceeding the power supply voltage when said power supply voltage is decreasing.
Claim 2
Dependent Claim
103 words
In a signal voltage level sensing circuit; first means operable to sense the difference between a signal voltage and a predetermined reference voltage; a memory means operably connected to receive and store the output signal of said first means; a second means operably connected to said memory means and operable to increase the current and the voltage available from said memory means; means for controlling a minimum duration of input signal to which said memory means responds; and, means for preventing the magnitude of the voltages of said memory means from exceeding the power supply voltage when said power supply voltage is decreasing.
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) | 1979-05-25 | 1979-11-24 | 1980-05-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-05-25 | 1983-11-24 | 1984-05-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-05-25 | 1987-11-24 | 1988-05-25 | $7700.00 | Window Closed / Lapsed |