US4190796A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pressure detecting apparatus having linear output characteristic
Assignee: Toshiba Corp
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Filing: 1978-05-24
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Granted: 1980-02-26
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Expires: 1998-05-24
Abstract
Abstract A pressure detecting apparatus which comprises a bridge circuit with semiconductor pressure elements; a constant voltage circuit for applying voltage to the bridge circuit; an amplifier circuit for amplifying the output of the bridge circuit thereby to provide an electrical signal proportional to the pressure variation; and a voltage correcting circuit connected between the input of the amplifier circuit and the input of the bridge circuit for amplifying the output of the bridge circuit to feed it back to the bridge circuit, and in which the output of the voltage correcting circuit and the output of the constant voltage circuit are applied to the bridge circuit to improve the linearity of the response characteristic or the pressure-electrical signal output characteristic.
Inventors
- 👤 Akira Ishii
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 22:44
CPC Classifications
G; G01; G01L; G01L9/00; G01L9/02; G01L9/06; G01L9/065
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
123 words
A pressure detecting apparatus comprising: a bridge circuit having semiconductor pressure sensitive elements; means for supplying a constant voltage to said bridge circuit wherein said constant voltage supplying means includes a voltage controlling amplifier having a reference voltage input, and a resistance element connected to the reference voltage input of the voltage controlling amplifier, the resistance-temperature coefficient of the resistance element being equal to or higher than those of the semiconductor pressure sensitive elements in said bridge circuit; an amplifier for amplifying the output of said bridge circuit; and a voltage correcting means connected between the input of said amplifier and the input of said bridge circuit for feeding the output of said bridge circuit back to the input of said bridge circuit.
Claim 2
Dependent Claim
123 words
A pressure detecting apparatus comprising: a bridge circuit having semiconductor pressure sensitive elements; means for supplying a constant voltage to said bridge circuit wherein said constant voltage supplying means includes a voltage controlling amplifier having a reference voltage input, and a resistance element connected to the reference voltage input of the voltage controlling amplifier, the resistance-temperature coefficient of the resistance element being equal to or higher than those of the semiconductor pressure sensitive elements in said bridge circuit; an amplifier for amplifying the output of said bridge circuit; and a voltage correcting means connected between the input of said amplifier and the input of said bridge circuit for feeding the output of said bridge circuit back to the input of said bridge circuit.
Claim 3
Dependent Claim
19 words
The apparatus recited in claim 1, including: a variable resistor circuit connected between both terminals of said resistance element.
Claim 4
Dependent Claim
94 words
A pressure detecting apparatus comprising: a bridge circuit having semiconductor pressure sensitive elements; means for supplying a constant voltage to said bridge circuit; an amplifier for amplifying the output of said bridge circuit; a voltage correcting means connected between the input of said amplifier and the input of said bridge circuit for feeding the output of said bridge circuit back to the input of said bridge circuit; and a first voltage division resistance circuit connected to the input terminals of said bridge circuit and having an output terminal connected to said voltage correcting means.
Claim 5
Dependent Claim
94 words
A pressure detecting apparatus comprising: a bridge circuit having semiconductor pressure sensitive elements; means for supplying a constant voltage to said bridge circuit; an amplifier for amplifying the output of said bridge circuit; a voltage correcting means connected between the input of said amplifier and the input of said bridge circuit for feeding the output of said bridge circuit back to the input of said bridge circuit; and a first voltage division resistance circuit connected to the input terminals of said bridge circuit and having an output terminal connected to said voltage correcting means.
Claim 6
Dependent Claim
60 words
The apparatus recited in claim 3, wherein: said voltage supplying means includes a voltage controlling amplifier having a reference voltage input, and a resistance element connected to the reference voltage input of the voltage controlling amplifier, the resistance-temperature coefficient of the resistance element being equal to or higher than those of the semiconductor pressure sensitive elements in said bridge circuit.
Claim 7
Dependent Claim
19 words
The apparatus recited in claim 4, including: a variable resistor circuit connected between both terminals of said resistance element.
Claim 8
Dependent Claim
33 words
The apparatus recited in claim 3 wherein said voltage correcting means includes: an operational amplifier, and a variable resistor circuit connected to the operational amplifier for varying the output of said operational amplifier.
Claim 9
Dependent Claim
75 words
The apparatus recited in claim 3, wherein said constant voltage supplying means includes: a voltage controlling amplifier having two inputs; a resistance element connected to one input of the amplifier for providing a reference input voltage, and a second voltage division resistance circuit connected to the input terminals of said bridge circuit and having a terminal connected to the other input of the voltage controlling amplifier and to the output of said voltage correcting circuit.
Claim 10
Dependent Claim
26 words
The apparatus recited in claim 7, wherein: said resistance element has a resistance-temperature coefficient equal to or higher than those of said semiconductor pressure sensitive elements.
Claim 11
Dependent Claim
19 words
The apparatus recited in claim 8, including: a variable resistor circuit connected between both terminals of said resistance element.
Claim 12
Dependent Claim
138 words
A pressure detecting apparatus comprising: a bridge circuit having semiconductor pressure sensitive elements; means for supplying a constant voltage to said bridge circuit; an amplifier for amplifying the output of said bridge circuit; and a voltage correcting means connected between the input of said amplifier and the input of said bridge circuit for feeding the output of said bridge circuit back to the input of said bridge circuit; said constant voltage supplying means including a voltage controlling amplifier having two inputs; a resistance element connected to one input of the voltage controlling amplifier for providing a reference input voltage; and a second voltage division resistance circuit connected to the input terminals of said bridge circuit and having a terminal connected to the other input of said voltage controlling amplifier and to the output of said voltage correcting means.
Claim 13
Dependent Claim
138 words
A pressure detecting apparatus comprising: a bridge circuit having semiconductor pressure sensitive elements; means for supplying a constant voltage to said bridge circuit; an amplifier for amplifying the output of said bridge circuit; and a voltage correcting means connected between the input of said amplifier and the input of said bridge circuit for feeding the output of said bridge circuit back to the input of said bridge circuit; said constant voltage supplying means including a voltage controlling amplifier having two inputs; a resistance element connected to one input of the voltage controlling amplifier for providing a reference input voltage; and a second voltage division resistance circuit connected to the input terminals of said bridge circuit and having a terminal connected to the other input of said voltage controlling amplifier and to the output of said voltage correcting means.
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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) | 1983-02-25 | 1983-08-27 | 1984-02-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-02-25 | 1987-08-27 | 1988-02-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-02-25 | 1991-08-27 | 1992-02-26 | $7700.00 | Window Closed / Lapsed |