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:
Jul. 24, 2001
Filed:
Aug. 29, 2000
John M. Hawkins, Greenwood, IN (US);
Rolls-Royce Corporation, Indianapolis, IN (US);
Abstract
An aircraft (,) having turboprop propulsion has a plurality of gas turbine engines (,), each with a two stage reduction gearbox (,) with the engine output shaft (,A) inline with the propeller drive output shaft (,) to drive a propeller (,) in front of the engine in a tractor mode of propulsion. The input gear reduction stage (,) and output gear reduction stage (,) share a plurality layshafts (,) mounted in fixed circularly-spaced relation to each other about the axis of the output shafts in the mechanical housing in the aircraft. Each layshaft of said plurality of layshafts has a layshaft first end toward the rear, input end of the gearbox, and a layshaft second end toward the output, front end of the gearbox. The layshaft gears are arranged to avoid any net thrust loading of the layshafts. Spur (,) and double helical (,) are used in FIG.,while spur gears,and,are used in FIG.,with suitable helix settings to neutralize end thrust on layshaft,Cantilever layshaft input gear (,) mounting in rear bearings (,) enables it to share some layshaft output gear,load sharing with the front bearing (,). A torquemeter (,) is conveniently situated at the gearbox input end. The engine output gear (,) and gearbox output gear (,), and propeller (,) all have colinear rotational axes.