Air-fuel ratio controller

Abstract

Abstract PURPOSE: To effect the stable control of air fuel ratio in the low-load run of an engine, by providing two flow control valves in an accessory air passage. CONSTITUTION: An accessory intake pipe 9 is provided to supply additional air from an air cleaner 2 to an intake pipe 5 at the downstream side of a throttle valve 4. The additional air is bypassed off a carburetor 3 and the throttle valve 4. A diaphragm chamber 13 of a first air control valve 10 is connected to an electromagnetic pressure control mechanism 30 through a pipe 51. When the air fuel ratio is smaller than a theoretical one, a solenoid valve 31 is energized another solenoid valve 32 is deenergized to conduct the intake negative pressure from the intake pipe 5 to the diaphragm ghamber 13 through the pipes 51, 53 to raise the degree of opening of a valve element 12 attahced to a diaphragm to increase the flow rate of the additional air. In the load low-load run, the degree of opening of a valve element 22 of a second air control valve 20 is lowered to prevent the flow rate of the additional air from greatly fluctuating due to change in the degree of opening of the first air control valve 10. COPYRIGHT: (C)1980,JPO&Japio

Inventors

• 👤 Tokio Kohama
• 👤 Tadashi Hattori
• 👤 Hideki Obayashi
• 👤 Kimiaki Yamaguchi

Bibliographic Details