US4352346A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electronic control system for a carburetor
Assignee: Subaru Corp
•
Filing: 1980-03-27
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Granted: 1982-10-05
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Expires: 2000-03-27
Abstract
Abstract An electronic control system for a carburetor of an internal combustion engine for controlling the air-fuel ratio to a value providing satisfactory cold engine operating performance. The system comprises an automatic choke device having a heater operative in response to the temperature of the device to close the choke valve, an oxygen sensor for detecting the content of the exhaust gases, an air-fuel ratio controlling means, and an electronic control means selectively operative to the signals from the oxygen sensor and the automatic choke device. The heater of the automatic choke device is a PTC heater, the resistance of which increases with the increase of the temperature thereof. The air-fuel ratio control means comprises an electromagnetic valve for controlling the fuel supply or air flow rate. When the oxygen sensor does not operate in the cold, the electronic control means is operated in accordance with the signal from the automatic choke device to actuate the air-fuel ratio control means for correcting the air-fuel ratio provided by the automatic choke device according to the current flowing through the heater to a value providing satisfactory operating performance.
Inventors
- 👤 Hisashi Osano
- 👤 Takuro Morozumi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 20:19
CPC Classifications
F; F02; F02M; F02M7/00; F02M7/12; F02M7/18; F02M7/20; F02D; F02D41/00; F02D41/02; F02D41/04; F02D41/06; F02D41/068; F02D41/14; F02D41/1438; F02D41/1486; F02D41/1488; F02D41/149; F02M1/00; F02M1/08; F02M1/10; F02M1/12
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
152 words
An electronic control system for a carburetor of an internal combustion engine having an induction passage means and an air-fuel mixture supply means, comprising: a choke valve disposed in said induction passage means, bimetal means for actuating said choke valve, a heater for heating said bimetal means, detecting means for detecting the content of exhaust gases, control means for controlling the air-fuel ratio of the mixture supplied by said air-fuel mixture supply means, electronic control means for actuating said air-fuel ratio control means, said electronic control means for being responsive to current passing through said heater and to an output signal from said detecting means, respectively, such that the air-fuel ratio is controlled to a value providing satisfactory cold engine operating performance by said current passing through said heater, and is controlled to the stoichiometric air-fuel ratio by said output signal from said detecting means when the engine has been warmed-up, respectively.
Claim 2
Dependent Claim
152 words
An electronic control system for a carburetor of an internal combustion engine having an induction passage means and an air-fuel mixture supply means, comprising: a choke valve disposed in said induction passage means, bimetal means for actuating said choke valve, a heater for heating said bimetal means, detecting means for detecting the content of exhaust gases, control means for controlling the air-fuel ratio of the mixture supplied by said air-fuel mixture supply means, electronic control means for actuating said air-fuel ratio control means, said electronic control means for being responsive to current passing through said heater and to an output signal from said detecting means, respectively, such that the air-fuel ratio is controlled to a value providing satisfactory cold engine operating performance by said current passing through said heater, and is controlled to the stoichiometric air-fuel ratio by said output signal from said detecting means when the engine has been warmed-up, respectively.
Claim 3
Dependent Claim
16 words
An electronic control system according to claim 1 wherein said detecting means is an oxygen sensor.
Claim 4
Dependent Claim
38 words
An electronic control system according to claim 1 wherein said air-fuel ratio control means comprises an on-off electro magnetic valve and said electronic control means is adapted to produce on-off pulses for operating said air-fuel ratio control means.
Claim 5
Dependent Claim
17 words
An electronic control system according to claim 1 wherein said heater is a positive temperature coefficient heater.
Claim 6
Dependent Claim
57 words
The electronic control system according to claim 1 or 2, wherein: said control means includes a control start judgement circuit means for cutting off said output signal from said detecting means when said output signal is below a predetermined level and for cutting off a signal of said current when said output signal reaches another predetermined level.
Claim 7
Dependent Claim
17 words
An electronic control system according to claim 5 wherein said heater is a positive temperature coefficient heater.
Claim 8
Dependent Claim
138 words
An electronic control system for a carburetor of an internal combustion engine having an induction passage means and an air-fuel mixture supply means, comprising: a choke valve disposed in said induction passage means, bimetal means for actuating said choke valve, an automatically controllable heater for heating said bimetal means, control means for controlling the air-fuel ratio of the mixture supplied by said air-fuel mixture supply means, electronic control means for actuating said air-fuel ratio control means, said electronic control means for being responsive to current passing through said heater for controlling the air-fuel ratio to a value providing satisfactory cold engine operating performance by said current passing through said heater, said air-fuel ratio control means comprises an on-off electromagnetic valve and said electronic control means is adapted to produce on-off pulses for operating said air-fuel ratio control means.
Claim 9
Dependent Claim
138 words
An electronic control system for a carburetor of an internal combustion engine having an induction passage means and an air-fuel mixture supply means, comprising: a choke valve disposed in said induction passage means, bimetal means for actuating said choke valve, an automatically controllable heater for heating said bimetal means, control means for controlling the air-fuel ratio of the mixture supplied by said air-fuel mixture supply means, electronic control means for actuating said air-fuel ratio control means, said electronic control means for being responsive to current passing through said heater for controlling the air-fuel ratio to a value providing satisfactory cold engine operating performance by said current passing through said heater, said air-fuel ratio control means comprises an on-off electromagnetic valve and said electronic control means is adapted to produce on-off pulses for operating said air-fuel ratio control 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) | 1985-10-04 | 1986-04-05 | 1986-10-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-10-04 | 1990-04-05 | 1990-10-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-10-04 | 1994-04-05 | 1994-10-05 | $7700.00 | Window Closed / Lapsed |