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. 25, 2011
Filed:
Jun. 21, 2007
Martin Clausen, Bjerringbro, DK;
Martin Clausen, Bjerringbro, DK;
Sauer-Danfoss ApS, Nordborg, DK;
Abstract
The invention provides a fluid controller for controlling a machine, e.g. for steering a vehicle. The controller comprises a housing defining an inlet port connected to the source and an outlet port connected to the pressure operated device. The flow rate is controlled by movement of a valve member within the housing, and a processor provides a reference which is indicative of a desired position of the valve member relative to the housing. The fluid controller comprises a fault detection system based on an observer. The observer calculates a theoretically correct position of the valve member relative to the housing for a given reference, and compares this position to an obtained position of the valve member relative to the housing. The difference between the positions is compared with a threshold value. In order to dynamically change the sensitivity of the system, the threshold value is scaled based on a gradient of the reference.