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:
Mar. 10, 1992
Filed:
Mar. 22, 1991
Gary Everingham, Chatham, CA;
Thomas A Davenport, Chatham, CA;
Siemens Automotive Limited, Chatham, CA;
Abstract
EGR is controlled by a valve whose actuator is a moving electromagnetic coil through which control current representing the desired degree of valve opening is conducted. The coil is disposed in an air gap of a magnetic circuit such that the magnetic flux passes radially through the coil. A coil spring biases the valve closed when there is no current flow through the coil. When control current is conducted through the coil, there is an interaction with the magnetic flux causing the exertion of an electromagnetic force on the coil against the spring force. Relative pressure acting on opposite sides of the valve will assist the coil motion. As a result the coil moves in a direction to increasingly compress the spring until the spring force balances the electromagnetic force. Consequently the valve is opened in an amount proportional to the control current. The motion of the coil is also electromagnetically damped, and a position sensor provides a feedback signal of the valve position.