Patent US2721264A successfully refreshed from Google Patents.
US3741015A
Expired / Lapsed
US
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Precision pressure gauge
Assignee: Texas Instruments Inc
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Filing: 1971-03-01
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Granted: 1973-06-26
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Expires: 1991-03-01
Abstract
Abstract A precision pressure gauge including Bourdon tube has a direct linear relation between applied pressure and Bourdon tube angle of deflection. An electrical circuit applies a continuously adjusted offset current to a transducer in order to apply the appropriate correction at any point on the Bourdon tube error curve.
Inventors
- 👤 K Moss
- 👤 W Hicks
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 02:08
CPC Classifications
G; G01; G01L; G01L9/00; G01L9/0026
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
216 words
A pressure gauge which comprises: a. a hollow helical tube supported with one end thereof fixed and the other end moveable; b. a mirror mounted at the other end of said tube and at the axis thereof for rotation relative to said axis and dependent upon the movement at said other end of said tube; c. structure for establishing a pressure differential across the walls of said tube to move said other end; d. a sensing means for directing a beam of light onto said mirror and including light sensitive means for detecting the reflected light and producing an electrical current i1 in response thereto; e. circuit means for producing a correction current i2; f. summing means coupled to current i1 and i2 for producing a sum current i3; g. control means responsive to current i3 for adjusting currents i1 and i2 until i3 0, said control means comprising a servo motor coupled to rotate said sensing means, thereby changing the angle of incidence of the reflected light and thus changing current i1; h. said circuit means comprising an adjustable resistor having a wiper coupled to said servo motor, a second adjustable resistor for off-setting an error at a maximal pressure state and a third adjustable resistor for offsetting an error at a medial pressure state.
Claim 2
Dependent Claim
216 words
A pressure gauge which comprises: a. a hollow helical tube supported with one end thereof fixed and the other end moveable; b. a mirror mounted at the other end of said tube and at the axis thereof for rotation relative to said axis and dependent upon the movement at said other end of said tube; c. structure for establishing a pressure differential across the walls of said tube to move said other end; d. a sensing means for directing a beam of light onto said mirror and including light sensitive means for detecting the reflected light and producing an electrical current i1 in response thereto; e. circuit means for producing a correction current i2; f. summing means coupled to current i1 and i2 for producing a sum current i3; g. control means responsive to current i3 for adjusting currents i1 and i2 until i3 0, said control means comprising a servo motor coupled to rotate said sensing means, thereby changing the angle of incidence of the reflected light and thus changing current i1; h. said circuit means comprising an adjustable resistor having a wiper coupled to said servo motor, a second adjustable resistor for off-setting an error at a maximal pressure state and a third adjustable resistor for offsetting an error at a medial pressure state.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-06-25 | 1976-12-25 | 1977-06-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-06-25 | 1980-12-25 | 1981-06-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-06-25 | 1984-12-25 | 1985-06-26 | $7700.00 | Window Closed / Lapsed |