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:
Mar. 15, 1988
Filed:
Apr. 30, 1985
Geoffrey S Hedrick, Malvern, PA (US);
Steven L Tomlinson, Coatesvile, PA (US);
Smiths Industries Aerospace & Defence Systems Inc., Malvern, PA (US);
Abstract
A universal fuel quantity indicator apparatus (100,102) includes a digital fuel quantity indicator (100) having an internal microprocessor control unit (104) and a removably connectable digital calibration trim unit interface (102) which enables the fuel quantity indicator (100) to be reconfigured for different fuel tanks by varying selectable fuel tank parameters, such as constants associated with a fuel quantity determination based on calculations of capacitance of a tank capacitor array (110) and a compensator capacitor (112). The interface (102) includes up/down steering control buttons (140,142) which control selection and storage of the selected parameters, a mode selection jumper (154) which selects between a RUN mode and a CALIBRATE mode for the indicator (100), and an alternate static memory (108) which stores the configured parameters for loading to the indicator internal static memory (150) associated with the microprocessor (104) in the CALIBRATE mode to configure the indicator (100) for a specific fuel tank. The indicator display (130) is used in the CALIBRATE mode to display the parameters being selected to configure the indicator (100) for a specific fuel tank and in the RUN mode to display the measured fuel quantity information for the configured fuel tank. The control program for both the RUN and CALIBRATE modes is resident in the indicator internal static memory (150) and is accessed by the interface (102) in the CALIBRATE mode to accomplish the parameter selection needed to reconfigure the universal indicator (100) for a specific fuel tank, such as for an aircraft.