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:
Sep. 23, 2003
Filed:
Jun. 29, 2001
Craig Andrew Weldon, Chatham, CA;
Raymond Rasokas, Thamesville, CA;
Siemens VDO Automotive Inc., Chatham, CA;
Abstract
A leak detection system for a fuel system of an automotive vehicle has a diaphragm pump that is repeatedly stroked to pressurize vapor containment space of the fuel system during a leak detection test. A restriction is disposed between the pump and the space being pressurized to cause a real time pressure trace of pressure between the pump and the restriction to comprise a succession of pulses having peaks and valleys. Data from the first pump burst of the trace is used to adjust the number of times the pump is stroked during subsequent bursts to maintain substantially constant mass airflow into the space during each burst, thereby compensating for change in pump efficiency.