US3624640A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Multiple-speed position-measuring system
Assignee: Inductosyn Corp
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Filing: 1968-06-17
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Granted: 1971-11-30
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Expires: 1988-06-17
Abstract
Abstract A multiple-speed position-measuring system comprising a plurality of position-measuring devices of different significances, the relatively movable members of the devices being connected together for movement at the same mechanical speed. The improvement resides in supplying analog signals, at a certain frequency, to one of the devices, and supplying to other of the devices analog signals at frequencies harmonically related to the certain frequency, the devices thereby having sensitivities in proportion to the respective frequencies. For example, a device supplied with a fundamental frequency F may provide a coarse error signal, and another device supplied with the 25th harmonic (25F) may provide a fine error signal. Analog signals at harmonically related frequencies may be provided by appropriately filtering a rectangular wave signal produced by a digital to analog converter.
Inventors
- 👤 Robert Z Geller
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 11:13
CPC Classifications
G; G05; G05D; G05D3/00; G05D3/12; G05D3/20; G05D3/203; G05B; G05B19/00; G05B19/02; G05B19/18; G05B19/19; G05B19/33; G05D3/14; G05D3/1436
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
240 words
Multiple-speed position-measuring system including a digitalto-analog converter, a position-measuring device having inductively related, relatively movable members supplying an analog signal for controlling a servomotor in accordance with a digital input supplied tO said converter, the improvement wherein said converter includes means for supplying trigonometrically related signals each of a plurality of harmonically related first and second frequencies, and means for supplying said first and second frequencies as inputs of corresponding grades of sensitivity to one of said relatively movable members of said position-measuring device, whereby the other member of said position-measuring device produces a corresponding plurality of error outputs for controlling said servomotor, said digital-toanalog converter including means for generating at least one pair of pulses symmetrically disposed on each side of a cyclically recurring reference position, first means responsive to one pair of said pulses for producing a first plurality of analog signals having frequencies harmonically related to the cyclical recurrence rate of the reference position, each of said analog signals representing a trigonometric function having an amplitude as a function of the position represented by said digital input, and second means responsive to said one pair of pulses for producing a second plurality of analog signals having frequencies harmonically related to the cyclical recurrence rate of the reference position, each of said second plurality of signals representing a trigonometric cofunction of said trigonometric function having an amplitude as a function of the position represented by said digital input.
Claim 2
Dependent Claim
240 words
Multiple-speed position-measuring system including a digitalto-analog converter, a position-measuring device having inductively related, relatively movable members supplying an analog signal for controlling a servomotor in accordance with a digital input supplied tO said converter, the improvement wherein said converter includes means for supplying trigonometrically related signals each of a plurality of harmonically related first and second frequencies, and means for supplying said first and second frequencies as inputs of corresponding grades of sensitivity to one of said relatively movable members of said position-measuring device, whereby the other member of said position-measuring device produces a corresponding plurality of error outputs for controlling said servomotor, said digital-toanalog converter including means for generating at least one pair of pulses symmetrically disposed on each side of a cyclically recurring reference position, first means responsive to one pair of said pulses for producing a first plurality of analog signals having frequencies harmonically related to the cyclical recurrence rate of the reference position, each of said analog signals representing a trigonometric function having an amplitude as a function of the position represented by said digital input, and second means responsive to said one pair of pulses for producing a second plurality of analog signals having frequencies harmonically related to the cyclical recurrence rate of the reference position, each of said second plurality of signals representing a trigonometric cofunction of said trigonometric function having an amplitude as a function of the position represented by said digital input.
Claim 3
Dependent Claim
58 words
A system according to claim 1, wherein said cyclical recurrence rate determines the fundamental frequency of said first and second pluralities of signals, said first and second signals each comprising signals at the fundamental frequency and signals at an odd harmonic of said fundamental frequency, said harmonic signals having amplitudes proportional to the amplitude of the fundamental signal.
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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) | 1974-11-29 | 1975-05-31 | 1975-11-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-11-29 | 1979-05-31 | 1979-11-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-11-29 | 1983-05-31 | 1983-11-30 | $7700.00 | Window Closed / Lapsed |