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:
Aug. 26, 2003
Filed:
Apr. 12, 2001
Kirk D. Doane, Essexville, MI (US);
John D. Zmierski, Cass City, MI (US);
Walbro Corporation, Cass City, MI (US);
Abstract
A fuel pressure regulation system for an internal combustion engine to regulate fuel pressure using a two-state pressure switch. In addition to the pressure switch, the system includes a control circuit, a current sensor, and a fuel pressure control device such as a fuel pump. The control circuit uses the pressure switch to sense whether the downstream fuel pressure is above or below a desired reference pressure. When below the reference pressure, the control circuit drives the fuel pump at full on to increase the fuel line pressure to the reference pressure. Once the fuel pressure rises and increases to or past the reference pressure, the pressure switch changes state, at which point the current sensor is used to sample and record the magnitude of the electric current supplied to the fuel pump at the moment the switch state changes. As long as the fuel line pressure is above the reference pressure, this stored value is used as a reference value in conjunction with the current measurement reading from the current sensor to provide closed loop control of the fuel pump operating current.