The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 17, 1980
Filed:
Aug. 11, 1978
Masaharu Sumiyoshi, Toyota, JP;
Setsuro Sekiya, Toyota, JP;
Katsuhiko Motosugi, Toyota, JP;
Junzo Uozumi, Nagoya, JP;
Tsuneo Ando, Chiryu, JP;
Yuzo Takeuchi, Nagoya, JP;
Mikio Minoura, Nagoya, JP;
Toyota Jidosha Kogyo Kabushiki Kaisha, Toyota, JP;
Aisan Industry Co., Ltd., Ohbu, JP;
Abstract
An air-fuel ratio control apparatus for an internal combustion engine has an air valve disposed in an intake passage downstream of a throttle valve to cooperate therewith to define an air pressure chamber and operative to maintain a substantially constant pressure therein. A fuel circuit includes a fuel discharge port open to the intake passage and a fuel-metering orifice operatively associated with the air valve such that the fuel-flowing section of the orifice is varied in proportion to the air-flowing section of the air valve. A constant differential fuel pressure valve is disposed in the fuel circuit to maintain a substantially constant fuel pressure difference across the fuel metering orifice during normal engine operation. The differential fuel pressure valve is mechanically operatively connected to a piston-cylinder assembly into which the fuel pressure upstream of the fuel-metering orifice is introduced. The position of the piston relative to the cylinder is varied when the engine operating condition is varied. The movement of the piston varies the fuel-flowing section of the differential fuel pressure valve thereby to vary the fuel pressure difference across the fuel-metering orifice whereby the air-fuel ratio is varied when the engine operating condition is varied.