Blade constraining structure

Claim 1

In an axial flow apparatus having stator and rotor elements, a blade constraining structure comprising: a first rotor element having axially opposed faces and a plurality of open-ended generally radial slots extending from one face to the other, with each slot having side walls which are undercut to provide inwardly directed abutment faces; a second rotor member axially spaced from said first member and including an axially extending circumferential flange, the tip of which is in closely spaced opposing relation to said slots and is axially undercut to provide an inwardly directed surface; a wedge ring whose outer radial annular surface is axially overcut to provide an outwardly directed surface abutting said inwardly directed surface of said flange, such that under the influence of centrifugal loading said wedge ring circumferentially expands and said overcut surface slides over said undercut surface in both an outward radial direction and an axial direction, effecting an axial translation of said wedge ring; a plurality of blades having root portions inserted into said slots so that the forward inserted face of each root abuts said wedge ring, wherein each root is thickened to provide outwardly extending shoulders which abut the inwardly extending shoulders of said slots so as to radially retain said blades under centrifugal loading; locking means constraining the other face of each root to inhibit axial movement of said roots such that under centrifugal loading the axial translation of said wedge ring is directed against the abutting root faces and cooperates with said locking means to further restrict axial movement of said blades.