US4622638A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ionization probe output interface circuit
Assignee: Visteon Global Technologies Inc
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Filing: 1983-12-22
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Granted: 1986-11-11
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Expires: 2003-12-22
Abstract
Abstract The capacitive effect of a coaxial cable coupled to an ionization probe is reduced by an operational amplifier which applies a constant bias voltage to the coaxial cable.
Inventors
- 👤 Robert L. Anderson
- 👤 William R. McDonald
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 19:10
CPC Classifications
G; G01; G01N; G01N27/00; G01N27/62; G01N27/626; F; F02; F02D; F02D35/00; F02D35/02; F02D35/021; F02P; F02P17/00; F02P17/12; F02P5/00; F02P5/04; F02P5/145; F02P5/1455; F02P2017/125; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/40
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
155 words
An ionization probe interface circuit means for improving the response time of an ionization probe by eliminating the capacitive effect of a coaxial cable coupling said ionization probe and said ionization probe interface circuit means, said ionization probe interface circuit means including: an operational amplifier means for applying a constant bias voltage to said coaxial cable, said operational amplifier means applying a positive voltage bias to said ionization probe with respect to a ground potential; current detector means coupled to said ionization probe through said coaxial cable for producing a voltage pulse in response to a current output from said ionization probe; a level detector coupled to said current detector means for producing a square wave pulse in response to a voltage output from said current detector means; and a microprocessor means coupled to said level detector for generating signals controlling engine operating parameters in response to the square wave output of said level detector.
Claim 2
Dependent Claim
155 words
An ionization probe interface circuit means for improving the response time of an ionization probe by eliminating the capacitive effect of a coaxial cable coupling said ionization probe and said ionization probe interface circuit means, said ionization probe interface circuit means including: an operational amplifier means for applying a constant bias voltage to said coaxial cable, said operational amplifier means applying a positive voltage bias to said ionization probe with respect to a ground potential; current detector means coupled to said ionization probe through said coaxial cable for producing a voltage pulse in response to a current output from said ionization probe; a level detector coupled to said current detector means for producing a square wave pulse in response to a voltage output from said current detector means; and a microprocessor means coupled to said level detector for generating signals controlling engine operating parameters in response to the square wave output of said level detector.
Claim 3
Dependent Claim
99 words
An ionization probe interface circuit means as recited in claim 1 wherein: said current detector includes: a first operational amplifier, for performing as a comparator, having a negative input coupled to said coaxial cable and coupled to a supply voltage through a first resistor, and having a positive input coupled to a supply voltage through a second resistor and coupled to ground through a third resistor, a feedback resistor coupled between the output and said positive input of said operational amplifier; and a series combination of a fourth resistor and a diode coupled in parallel with said feedback resistor.
Claim 4
Dependent Claim
68 words
An ionization probe interface circuit means as recited in claim 2 wherein said level detector includes: a second operational amplifier, for performing as a comparator, having a positive input coupled through a fifth resistor to the output of said first operational amplifier, a negative input coupled to a voltage threshold level and an output coupled to said positive input of said second operational amplifier through a sixth resistor.
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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) | 1989-11-10 | 1990-05-12 | 1990-11-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-11-10 | 1994-05-12 | 1994-11-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-11-10 | 1998-05-12 | 1998-11-11 | $7700.00 | Window Closed / Lapsed |