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:
Feb. 13, 1996
Filed:
Dec. 20, 1993
Donald E Wernberg, Rockford, IL (US);
Gregory A Molenaar, Loveland, CO (US);
Daniel F Miller, Beloit, WI (US);
Woodward Governor Company, Rockford, IL (US);
Abstract
A fuel metering unit for an aircraft gas turbine engine has both electronic and manual control, both compensated for altitude variations. A three-dimensional cam is used to control the position of a fuel metering valve. One axis of the 3-D cam is electronically controlled and another is mechanically controlled. Electronic control is the normal mode and sets the electronic axis to provide a fuel metering valve setting which delivers a mass flow rate to the engine as demanded by the position of the fuel lever as interpreted by the electronic control. Upon failure of the electronic control, the position of the 3-D cam along the electronic axis is mechanically locked so that any further changes in fuel metering valve position are a function solely of the position of the power lever as translated to the mechanical axis of the 3-D cam. Transfer from electronic to manual control is therefore 'bumpless.'