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:
Nov. 23, 2004
Filed:
Jul. 01, 2003
Johannes-Joerg Rueger, Vienna, AT;
Matthias Mrosik, Sparrhärmlingweg, DE;
Volker Pitzal, Waldstetten/Wissgoldingen, DE;
Udo Schulz, Vaihingen/Enz, DE;
Robert Bosch GmbH, Stuttgart, DE;
Abstract
A method is proposed for diagnosing the drive voltage for a piezoelectric actuator of an injector, in which the drive voltage is measured for the individual phases of the injection procedure. With respect to each control phase, a corresponding tolerance band is provided, which is set using the setpoint value of the drive voltage. The tolerance ranges are established as a function of operating and/or environmental conditions. If, for the individual drive cycles, the corresponding tolerance ranges are not reached, then, in response to repeated measurement, these erroneous measurements are counted. When a preestablished number for the erroneous measurements is exceeded, then an ongoing error is diagnosed. If, after a certain time, the number is not exceeded, then the counter is reset. In the case of an error, the error storage unit can be reset using a maintenance plug-in device during maintenance.