Patent US4030039A successfully refreshed from Google Patents.
US4030039A
Expired / Lapsed
US
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Function generator
Assignee: ABB Norden Holding AB
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Filing: 1976-03-17
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Granted: 1977-06-14
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Expires: 1996-03-17
Abstract
Abstract For the generation of inverse time characteristics for time-lag type over-current relays or the like, by approximation of the time function by means of individual, linear parts into a time function which is discontinuous at a number of break points. A plurality of amplifier circuits corresponding to the number of break points in the approximated time function each has at least one input and at least one output and operates as an ideal diode. The input of each of the amplifier circuits is connected to an input voltage source. An arrangement is provided for selectively connecting the output of each of the amplifier circuits to the input or output of the operational amplifier, depending on whether the linear part of the time function, determined by a selected amplifier circuit, has a greater or smaller derivative than the preceding linear part of the time function.
Inventors
- 👤 Tord Fahlgren
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 13:12
CPC Classifications
G; G06; G06G; G06G7/00; G06G7/12; G06G7/26; G06G7/28; H; H02; H02H; H02H3/00; H02H3/08; H02H3/093
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
203 words
Function generator for generation of inverse time characteristics by approximation of the time function by means of individual, linear parts into a time function which is discontinuous at a number of break points, comprising first and second operational amplifiers, each having at least one input and at least one output the output of said first operational amplifier being connected to the input of said second operational amplifier, a plurality of amplifier circuits corresponding to the number of break points in the approximated time function, each of said amplifier circuits having at least one input and one output and operating as an ideal diode to provide a predetermined linear part of said time function, each of said amplifier circuits having said input connected to an input voltage source, and each of said amplifier circuits including selecting means for independently connecting the output thereof to the input of said first operational amplifier to decrease the derivative of the linear part of the time function generated by the respective amplifier circuit, said selecting means alternatively connecting the amplifier circuit output to the input of said second operational amplifier to increase the derivative of the linear part of the time function generated by the respective amplifier circuit.
Claim 2
Dependent Claim
203 words
Function generator for generation of inverse time characteristics by approximation of the time function by means of individual, linear parts into a time function which is discontinuous at a number of break points, comprising first and second operational amplifiers, each having at least one input and at least one output the output of said first operational amplifier being connected to the input of said second operational amplifier, a plurality of amplifier circuits corresponding to the number of break points in the approximated time function, each of said amplifier circuits having at least one input and one output and operating as an ideal diode to provide a predetermined linear part of said time function, each of said amplifier circuits having said input connected to an input voltage source, and each of said amplifier circuits including selecting means for independently connecting the output thereof to the input of said first operational amplifier to decrease the derivative of the linear part of the time function generated by the respective amplifier circuit, said selecting means alternatively connecting the amplifier circuit output to the input of said second operational amplifier to increase the derivative of the linear part of the time function generated by the respective amplifier circuit.
Claim 3
Dependent Claim
98 words
A function generator according to claim 1, said selecting means comprising: a first conductor including a fixed contact for each of said amplifier circuits is connected to the input of said first operational amplifier, a second conductor including a fixed contact for each of said amplifier circuits is connected to the input of said second operational amplifier, and a switch with a movable contact connected to the output of the associated amplifier circuit and arranged to cooperate with said fixed contacts to alternatively connect the associated amplifier circuit to the input of one of said two operational amplifiers.
Claim 4
Dependent Claim
63 words
A function generator according to claim 1 wherein each of said amplifier circuits includes means for varying the break point at which the respective amplifier circuit is actuated and means for adjusting the slope of the linear portion of the time function controlled by the respective amplifier circuit, said means for varying and said means for adjusting being operated independently from each other.
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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) | 1980-06-13 | 1980-12-13 | 1981-06-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-06-13 | 1984-12-13 | 1985-06-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-06-13 | 1988-12-13 | 1989-06-14 | $7700.00 | Window Closed / Lapsed |