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:
Jun. 21, 2011
Filed:
Dec. 27, 2007
Silke Haag, Abstatt, DE;
Silke Haag, Abstatt, DE;
Robert Bosch GmbH, Stuttgart, DE;
Abstract
A method to test for a leak in a fuel tank system of a motor vehicle includes a fuel tank is cut off during the overrun by means of at least one cutoff device, and the pressure, which builds up in the fuel tank within a specifiable time interval is acquired; if a specifiable maximum pressure or a specifiable vacuum threshold is not achieved, said cutoff device is opened and closed again after a specifiable time period, and a vacuum is produced and acquired in a subsequent vacuum phase, and a parameter, which characterizes the leak tightness, is determined and evaluated from the vacuum achieved within a specifiable time period and the overpressure, which is achieved, and the test for a leak is concluded; if the specifiable maximum pressure is achieved, a parameter characterizing the leak tightness is determined from the acquired overpressure and the specifiable overpressure threshold and is compared with a specifiable reference value and for the case that the determined parameter is smaller than the reference value, a leak-proof fuel tank system is suggested and the test for a leak is concluded, and if the determined parameter is greater than the specifiable reference value, the cutoff device is opened and a vacuum is produced and acquired in the fuel tank in a subsequent vacuum phase, whereby a leak-proof fuel tank system is then suggested if a specifiable vacuum threshold is achieved, and hence the test for a leak is concluded, and whereby the test for a leak is then concluded if the vacuum threshold is not achieved within a specifiable time period, and hence the parameter characterizing the leak tightness is evaluated.