US4549180A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process variable transmitter
Assignee: Toshiba Corp
•
Filing: 1982-08-13
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Granted: 1985-10-22
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Expires: 2002-08-13
Abstract
Abstract A process variable transmitter including a plurality of process variable detector units for detecting a primary process variable to be measured and secondary process variables not to be measured but which affect the primary process variable, a memory circuit for storing detected outputs supplied from the process variable detector units, a circuit for reading the detected outputs out of the memory circuit and then correcting the detected output indicative of the primary process variable based on the detected outputs indicative of the secondary process variables, and a power supply control for intermittently supplying electric power to the process variable detector units and the correcting circuit. The process variable transmitter corrects the primary process variable to precision and consumes a reduced amount of electric power.
Inventors
- 👤 Hisaki Masuda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 10:12
CPC Classifications
G; G08; G08C; G08C19/00; G08C19/02; G01; G01L; G01L27/00; G01L27/002; G01L27/005; G08C25/00
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
140 words
A process variable transmitter for transmitting a process variable to a receiving instrument at a location remote from said transmitter, comprising: a plurality of process variable detector units for detecting a primary process variable to be measured and for detecting secondary process variables which affect the primary process variable; a memory circuit for storing detected outputs supplied from the process variable detector units; processing means for reading the detected outputs of the memory circuit and then correcting the detected output indicative of the primary process variable based on the detected outputs indicative of the secondary process variables; means for converting the corrected detected output to an output current signal and for transmitting said current signal to said remote receiving instrument; and power supply control means for intermittently supplying electric power to the process variable detector units and the processing means.
Claim 2
Dependent Claim
140 words
A process variable transmitter for transmitting a process variable to a receiving instrument at a location remote from said transmitter, comprising: a plurality of process variable detector units for detecting a primary process variable to be measured and for detecting secondary process variables which affect the primary process variable; a memory circuit for storing detected outputs supplied from the process variable detector units; processing means for reading the detected outputs of the memory circuit and then correcting the detected output indicative of the primary process variable based on the detected outputs indicative of the secondary process variables; means for converting the corrected detected output to an output current signal and for transmitting said current signal to said remote receiving instrument; and power supply control means for intermittently supplying electric power to the process variable detector units and the processing means.
Claim 3
Dependent Claim
26 words
The process variable transmitter of claim 1, wherein said detector units, said memory circuit, said processing means and said power supply control are in one enclosure.
Claim 4
Dependent Claim
30 words
The process variable transmitter of claim 1, comprising; said plurality of process variable detector units including respective analog-digital converters; and said memory circuit storing the digital outputs of said converters.
Claim 5
Dependent Claim
37 words
The process variable transmitter of claim 1, comprising: an analog-digital converter connected between said detector units and said memory circuit and controlled by said power supply to convert analog output from said detector units to digital outputs.
Claim 6
Dependent Claim
20 words
The process variable transmitter of claim 1, wherein said memory processing means and said circuit operate in an analog domain.
Claim 7
Dependent Claim
43 words
The process variable transmitter of claim 1, wherein said power supply control means comprises: a constant voltage power source for applying power to said converting means and for producing a current for powering said detector units, said memory circuit and said processing means.
Claim 8
Dependent Claim
27 words
The process variable transmitter of claim 6, said output current signal is from 4 mA through 20 mA, and said powering current is less than 4 mA.
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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) | 1988-10-21 | 1989-04-22 | 1989-10-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-10-21 | 1993-04-22 | 1993-10-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-10-21 | 1997-04-22 | 1997-10-22 | $7700.00 | Window Closed / Lapsed |