Strut driveshaft for ram air turbine

摘要

A driveshaft for an aircraft ram air turbine includes a substantially cylindrical elongate portion, a first end extending from the elongate portion, and a second end extending from the elongate portion opposite the first end. The first and second ends each include a substantially frusto-conical section having a curved generatrix, such that distal portions of each of the first and second ends have smaller outer diameters than an outer diameter of the elongate portion. The elongate portion provides relatively high lateral stiffness and the first and second ends provide relatively low torsional stiffness, such that the driveshaft has a lateral natural frequency higher than an operating range of the driveshaft and has a torsional natural frequency below the operating range of the driveshaft.

主权项

1. A driveshaft for an aircraft ram air turbine, the driveshaft comprising:
an elongate portion, wherein the elongate portion is substantially cylindrical; a first end extending from the elongate portion; and a second end extending from the elongate portion opposite the first end, wherein the first and second ends each include a substantially frusto-conical section having a curved generatrix such that distal portions of each of the first and second ends have smaller outer diameters than an outer diameter of the elongate portion; wherein the first and second ends are mechanically connected to a driveline that extends between a power conversion device and a turbine; wherein at least one of the first and second ends further comprises:
a cylindrical portion located radially outward from the substantially frusto-conical section, wherein at least part of the cylindrical portion axially overhangs the substantially frusto-conical portion such that the cylindrical portion is separated from the distal portion of the corresponding first or second end by a radial gap, wherein the elongate portion provides higher lateral stiffness than the first and second ends, and wherein the first and second ends provide lower torsional stiffness than the elongate portion, such that the driveshaft has an overall lateral natural frequency higher than an operating range of the driveshaft and has an overall torsional natural frequency below the operating range of the driveshaft.