Patent US4660290A successfully refreshed from Google Patents.
US4660290A
Expired / Lapsed
US
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Inclination measuring instrument
Assignee: Topcon Corp
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Filing: 1985-12-12
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Granted: 1987-04-28
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Expires: 2005-12-12
Abstract
Abstract Inclination measuring instrument having a tube having a concave inside surface and filled with liquid so as to have a bubble, a first electrode provided on the outside surface of the tube opposite to the bubble, second and third electrodes provided on the outside surface of the tube opposite to the first electrode and located along the direction of shift of the bubble, a guard electrode provided on the outside surface of the tube to frame the first, second and third electrodes and to be supplied with a predetermined voltage, and processing means for connecting a first capacitor consisting of the first and second electrodes and second capacitor consisting of the first and third electrodes so as to calculate the inclination of the tube from the output of the first and second capacitors.
Inventors
- 👤 Nobuo Hori
- 👤 Takashi Yokokura
- 👤 Fumio Ohtomo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 04:50
CPC Classifications
G; G01; G01C; G01C9/00; G01C9/18; G01C9/24; G01C9/34; G01C9/02; G01C9/06
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
133 words
Inclination measuring instrument having a tube having a curved inside surface and filled with liquid so as to have a bubble, a first electrode provided on the outside surface of the tube opposite to the bubble, second and third electrodes provided on the outside surface of the tube opposite to the first electrode and located along the direction of shift of the bubble, a guard electrode provided on the outside surface of the tube to frame the first, second and third electrodes and to be supplied with a predetermined voltage, and processing means for connecting a first capacitor consisting of the first and second electrodes and second capacitor consisting of the first and third electrodes so as to calculate the inclination of the tube from the output of the first and second capacitors.
Claim 2
Dependent Claim
133 words
Inclination measuring instrument having a tube having a curved inside surface and filled with liquid so as to have a bubble, a first electrode provided on the outside surface of the tube opposite to the bubble, second and third electrodes provided on the outside surface of the tube opposite to the first electrode and located along the direction of shift of the bubble, a guard electrode provided on the outside surface of the tube to frame the first, second and third electrodes and to be supplied with a predetermined voltage, and processing means for connecting a first capacitor consisting of the first and second electrodes and second capacitor consisting of the first and third electrodes so as to calculate the inclination of the tube from the output of the first and second capacitors.
Claim 3
Dependent Claim
62 words
Inclination measuring apparatus in accordance with claim 1 in which said processing means has an integral circuit connected alternatively with the first and second capacitors, a square wave converter for converting the output of the integral circuit into a square wave, a counter for counting the output of the converter, and means for calculating the inclination from the output of the counter.
Claim 4
Dependent Claim
44 words
Inclination measuring apparatus in accordance with claim 1 in which one of (1) the first electrode and (2) the second and third electrodes are provided on the upper surface of the tube, and the other is provided on the lower surface of the tube.
Claim 5
Dependent Claim
128 words
Inclination measuring apparatus comprising a tube having a curved inside surface and filled with liquid so as to have a bubble adjacent the upper surface of said tube, a first electrode provided on the outer side surface of said tube, second and third electrodes provided on the outer side surface of the tube opposite said first electrode, a guard electrode provided on the outside surface of the tube to frame the first, second and third electrodes and to be supplied with a predetermined voltage, and processing means for connecting a first capacitor consisting of the first and second electrodes and a second capacitor consisting of the first and third electrodes so as to calculate the inclination of the tube from the output of the first and second capacitors.
Claim 6
Dependent Claim
128 words
Inclination measuring apparatus comprising a tube having a curved inside surface and filled with liquid so as to have a bubble adjacent the upper surface of said tube, a first electrode provided on the outer side surface of said tube, second and third electrodes provided on the outer side surface of the tube opposite said first electrode, a guard electrode provided on the outside surface of the tube to frame the first, second and third electrodes and to be supplied with a predetermined voltage, and processing means for connecting a first capacitor consisting of the first and second electrodes and a second capacitor consisting of the first and third electrodes so as to calculate the inclination of the tube from the output of the first and second capacitors.
References Cited (Backward Citations)
US3096591A
Cited
JPS5359461A
Cited
US4077132A
Cited
SU756199A1
Cited
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Cited
WO1983001304A1
Cited
US4536967A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-04-27 | 1990-10-27 | 1991-04-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-04-27 | 1994-10-27 | 1995-04-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-04-27 | 1998-10-27 | 1999-04-28 | $7700.00 | Window Closed / Lapsed |