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:
Oct. 31, 2006
Filed:
Jun. 01, 2005
Jurgen Thyroff, Harxheim, DE;
Jurgen Thyroff, Harxheim, DE;
GM Global Technology Operations, Inc., Detroit, MI (US);
Abstract
A method for detecting leaks in a fuel cell system that includes a hydrogen storage tank, a primary shut-off valve and a secondary shut-off valve in a supply line. At shut-down, the primary shut-off valve is closed and the stack is temporarily left operating. The pressure is measured in the supply line between the valves. When the measured pressure has reached a predetermined shut-down pressure, the secondary shut-off valve is closed. At the next system start-up, the pressure is measured before the shut-off valves are opened, and the measured pressure is compared with the stored pressure. If the current pressure measurement is lower than the stored pressure measurement, it is an indication that the supply line between the shut-off valves or the secondary valve leaks. If the measured pressure is higher than the stored pressure, it is an indication that the primary valve leaks.