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:
Nov. 04, 1980
Filed:
Jun. 20, 1979
Torazo Nishimiya, Mito, JP;
Masamitsu Okumura, Katsuta, JP;
Tomo Ito, Katsuta, JP;
Seisaku Numakura, Katsuta, JP;
Hitachi, Ltd., , JP;
Abstract
An exhaust gas recirculation control system for controlling the amount of exhaust gas subjected to recirculation to the air inlet depending on the amount of inlet air of an internal combustion engine. This system comprises a control valve disposed in an exhaust gas recirculation passage, for controlling the amount of exhaust gas recirculation, an orifice disposed in the recirculation passage, for creating a negative pressure upstream of the control valve, and a solenoid valve for generating a pressure which controls the control valve. The solenoid valve comprises a core formed therein with a hollow passage opened at one end to a valve portion, a plunger made of a magnetic material and having a valve seat opposing the open end to define the valve portion, a spring biasing the plunger in the opening direction of the valve portion, a first exciting coil generating, when passing therethrough a current proportional to the amount of inlet air, a force acting on the plunger to close the valve portion, and a second exciting coil generating, when passing therethrough a current in inverse proportion to the pressure downstream of the orifice, a force opposite to the force on the plunger due to the first exciting coil.