| 摘要 |
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. |
