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:
Jan. 25, 2000
Filed:
Mar. 06, 1998
Siemens Canada Limited, Mississauga, CA;
Abstract
A leak detection method for an on-board evaporative emission leak detection system that detects leakage from an evaporative emission space of a fuel system of an automotive vehicle. During a leak detection test, a vent valve closes, and a purge valve, that selectively communicates the evaporative emission space with the engine intake manifold, opens to cause vacuum to be drawn in the evaporative emission space. A vacuum regulator valve regulates evaporative emission space vacuum to a defined vacuum. Subsequently, the purge valve closes. Loss of vacuum, indicative of leakage, is signaled by a pressure sensor. An algorithm detects a substantially constant rate of vacuum loss and then measures the amount of loss over a defined time interval. That measurement is then compensated for volume of the evaporative emission space and rate of fuel volatilization to arrive at a value forming a basis for making a leakage determination.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile