US3873928A
Expired / Lapsed
US
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Reference wave generator using logic circuitry for providing substantially sinusoidal output
Assignee: General Electric Co
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Filing: 1972-03-08
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Granted: 1975-03-25
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Expires: 1992-03-08
Abstract
Abstract In a reference wave generator, a clock source synchronizes first and second step wave generators respectively producing output waves of first and second frequencies. The step wave generators have their outputs connected to a discriminator which provides a reference wave output having a frequency equal to the difference of the frequencies of the step waves applied to its inputs. In order to improve the output wave shape, one of the step wave generators produces a quasi-square wave which comprises a square wave having zero dwell between its positive and negative values.
Inventors
- 👤 David Logan Lafuze
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 02:37
CPC Classifications
H; H02; H02M; H02M7/00; H02M7/42; H02M7/44; H02M7/48; H03; H03B; H03B27/00
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
149 words
A reference wave generator comprising, in combination: a. a source of clock pulses; b. first and second step wave generators for producing step waves of different frequencies, at least one of which produces a quasi-square wave having a positive excursion and a negative excursion and a period of zero dwell between said positive and negative excursions, both said first and second wave generators being coupled to and synchronized by said clock source and; c. a discriminator couple to the outputs of said first and secOnd step wave generators for providing an output equal to the in-phase voltage minus the out-of-phase voltage of the outputs of said first and second step wave generators, whereby said discriminator provides an output whose average value is represented by a continuous wave of low harmonic content having a frequency equal to the difference between the frequencies of said first and second step wave generators.
Claim 2
Dependent Claim
149 words
A reference wave generator comprising, in combination: a. a source of clock pulses; b. first and second step wave generators for producing step waves of different frequencies, at least one of which produces a quasi-square wave having a positive excursion and a negative excursion and a period of zero dwell between said positive and negative excursions, both said first and second wave generators being coupled to and synchronized by said clock source and; c. a discriminator couple to the outputs of said first and secOnd step wave generators for providing an output equal to the in-phase voltage minus the out-of-phase voltage of the outputs of said first and second step wave generators, whereby said discriminator provides an output whose average value is represented by a continuous wave of low harmonic content having a frequency equal to the difference between the frequencies of said first and second step wave generators.
Claim 3
Dependent Claim
43 words
A reference wave generator according to claim 1 in which said first step wave generator comprises a square wave generator and said second step wave generator comprises a quasi-square wave generator whereby the output from said discriminator is a continuous trapezoidal wave form.
Claim 4
Dependent Claim
47 words
A reference wave generator according to claim 2 further comprising smoothing means coupled to the output of said discriminator, said smoothing means providing an output wave having a frequency equal to the difference of the frequencies provided by said square wave generator and said quasi-square wave generator.
Claim 5
Dependent Claim
25 words
A system according to claim 2 in which said first step wave generator provides a quasi-square wave having a zero-dwell of between 20* and 40*.
Claim 6
Dependent Claim
71 words
A system according to claim 4 in which said first step wave generator further comprises means for superimposing a signal on the output of said first step wave generator for a period of 20* to 40* on either side of the zero-dwell and having a frequency at least 10 times higher than the output frequency of said first reference wave generators for producing a substantially sinusoidal output wave from said discriminator.
Claim 7
Dependent Claim
65 words
A reference wave generator according to claim 1 in which said second step wave generator includes phase shifting means for providing additional outputs such that said second step wave generator provides N step waves, each phase displaced from the next by 360/N* and in which said discriminator discriminates each of said waves against a output of said first step wave generator and provides N outputs.
Claim 8
Dependent Claim
17 words
A reference wave generator according to claim 6 in which said phase shifting means comprise logic circuits.
Claim 9
Dependent Claim
31 words
A reference wave generator according to claim 7 in which said first step wave generator comprises a sqaure wave generator and said second step wave generator comprises a quasi-square wave generator.
Claim 10
Dependent Claim
47 words
A reference wave generator according to claim 8 further comprising smoothing means coupled to the output of said discriminator, said smoothing means providing an output wave having a frequency equal to the difference of the frequencies provided by said square wave generator and said quasi-square wave generator.
Claim 11
Dependent Claim
40 words
A reference wave generator according to claim 1 in which said first step wave generator comprises a quasi-square wave generator and said second step wave generator comprises a quasi-square wave generator whereby the output wave form is made substantially sinusoidal.
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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) | 1978-03-24 | 1978-09-23 | 1979-03-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-24 | 1982-09-23 | 1983-03-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-24 | 1986-09-23 | 1987-03-25 | $7700.00 | Window Closed / Lapsed |