US3934200A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Tachometer circuit
Assignee: Landis Tool Co
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Filing: 1975-01-31
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Granted: 1976-01-20
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Expires: 1995-01-31
Abstract
Abstract A D.C. tachometer circuit comprising a non-linear D.C. tachometer which produces an output voltage having an A.C. ripple, a first current path from the D.C. tachometer including means for removing the D.C. component of the output voltage of the tachometer, means for inverting and isolating the A.C. voltage ripple, and means for eliminating drift and the D.C. level of the inverted and isolated A.C. voltage-ripple, means for mixing the original output voltage of the D.C. tachometer including the A.C. ripple and the inverted and isolated A.C. voltage ripple to establish a non-linear ripple-free output voltage, and means for linearizing the non-linear ripple-free output voltage.
Inventors
- 👤 Stanley C. Schoonover
- 👤 Michael D. McIntosh
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 16:45
CPC Classifications
G; G01; G01P; G01P3/00; G01P3/42; G01P3/44; G01P3/46
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
105 words
A D.C. tachometer circuit comprising a non-linear D.C. tachometer which produces an output voltage having an A.C. ripple, a first current path from said D.C. tachometer including means for removing the D.C. component of the output voltage of the D.C. tachometer, means for inverting and isolating the A.C. voltage ripple, means for eliminating drift and the D.C. level of the inverted and isolated A.C. voltage ripple, means for mixing the original output voltage of the D.C. tachometer including the A.C. ripple and the inverted and isolated A.C. voltage ripple to establish a non-linear ripple-free output voltage, and means for linearizing said non-linear ripple-free output voltage.
Claim 2
Dependent Claim
105 words
A D.C. tachometer circuit comprising a non-linear D.C. tachometer which produces an output voltage having an A.C. ripple, a first current path from said D.C. tachometer including means for removing the D.C. component of the output voltage of the D.C. tachometer, means for inverting and isolating the A.C. voltage ripple, means for eliminating drift and the D.C. level of the inverted and isolated A.C. voltage ripple, means for mixing the original output voltage of the D.C. tachometer including the A.C. ripple and the inverted and isolated A.C. voltage ripple to establish a non-linear ripple-free output voltage, and means for linearizing said non-linear ripple-free output voltage.
Claim 3
Dependent Claim
19 words
A non-linear D.C. tachometer circuit according to claim 1 wherein said linearizing means further comprises overall linearity compensator means.
Claim 4
Dependent Claim
35 words
A non-linear D.C. tachometer circuit according to claim 2, wherein said linearizing means further comprises summing amplifier means for summing said non-linear ripple-free output voltage and the voltage produced by said overall linearity compensator means.
Claim 5
Dependent Claim
33 words
A non-linear D.C. tachometer circuit according to claim 3, further comprising means for selectively varying the gain of said summing amplifier for compensating the output voltage of the D.C. tachometer at low RPM'S.
Claim 6
Dependent Claim
14 words
A non-linear D.C. tachometer circuit according to claim 4, wherein said tachometer is brushless.
Claim 7
Dependent Claim
16 words
A non-linear D.C. tachometer circuit according to claim 5, wherein said removing means comprises a capacitor.
Claim 8
Dependent Claim
18 words
A non-linear D.C. tachometer circuit according to claim 6, wherein said inverting means comprises a unity gain amplifier.
Claim 9
Dependent Claim
17 words
A non-linear D.C. tachometer circuit according to claim 7, wherein said eliminating means comprises a second capacitor.
Claim 10
Dependent Claim
19 words
A non-linear D.C. tachometer circuit according to claim 8, wherein said mixing means comprises a second unity gain amplifier.
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) | 1979-01-19 | 1979-07-21 | 1980-01-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-01-19 | 1983-07-21 | 1984-01-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-01-19 | 1987-07-21 | 1988-01-20 | $7700.00 | Window Closed / Lapsed |