Abstract: A method of constructing an integral coupling system containing a sun gear is disclosed. An integral sun gear is provided that has a sun gear component and a connection shaft. A first straight flat inner edge is machined on a first diaphragm to use as a datum point, and then the straight flat edge is fixtured. A tapered outer edge is machined on the first diaphragm, and the first diaphragm is welded to the integral sun gear. The flat inner edge is generally perpendicular to a central axis of the connection shaft.

Abstract: Roller bearings, and struts and gas turbine engines using such bearings are provided. In this regard, a representative roller bearing for a gas turbine engine includes: a roller having a rolling surface and an end; a race having a flange and defining a raceway, the raceway terminating at the flange, the raceway being operative to receive the roller such that the rolling surface of the roller engages in rolling contact with the raceway; and a hard coating applied to the flange such that the end of the roller engages in sliding contact with the coating.

Abstract: A coupling system for connecting a sun gear to a shaft within a planetary gear train, includes a sun gear coupling connecting the sun gear to the shaft. The sun gear coupling has at least one undulant flexible section joined to an inflexible spindle for accommodating misalignment between the sun gear and the shaft. The flexible section comprises a cylindrical ring having a diameter greater than the diameter of the spindle, and joined to the spindle by two longitudinally spaced apart diaphragms. The juncture between the diaphragms, the ring, and the spindle is curved in cross section on an outer side to improve flexibility and minimize stress concentrations, and the inner sides of the diaphragms are straight edges which result in a non-symmetric contour of the diaphragm walls.

Abstract: A method of constructing an integral coupling system containing a sun gear is disclosed. An integral sun gear is provided that has a sun gear component and a connection shaft. A first straight flat inner edge is machined on a first diaphragm to use as a datum point, and then the straight flat edge is fixtured. A tapered outer edge is machined on the first diaphragm, and the first diaphragm is welded to the integral sun gear. The flat inner edge is generally perpendicular to a central axis of the connection shaft.

Abstract: A coupling system for connecting a sun gear to a shaft within a planetary gear train, includes a sun gear coupling connecting the sun gear to the shaft. The sun gear coupling has at least one undulant flexible section joined to an inflexible spindle for accommodating misalignment between the sun gear and the shaft. The flexible section comprises a cylindrical ring having a diameter greater than the diameter of the spindle, and joined to the spindle by two longitudinally spaced apart diaphragms. The juncture between the diaphragms, the ring, and the spindle is curved in cross section on an outer side to improve flexibility and minimize stress concentrations, and the inner sides of the diaphragms are straight edges which result in a non-symmetric contour of the diaphragm walls.

Abstract: A coupling system for connecting a sun gear to a shaft within a planetary gear train, includes a sun gear coupling connecting the sun gear to the shaft. The sun gear coupling has at least one undulant flexible section joined to an inflexible spindle for accommodating misalignment between the sun gear and the shaft. The flexible section comprises a cylindrical ring having a diameter greater than the diameter of the spindle, and joined to the spindle by two longitudinally spaced apart diaphragms. The juncture between the diaphragms, the ring, and the spindle is curved in cross section on an outer side to improve flexibility and minimize stress concentrations, and the inner sides of the diaphragms are straight edges which result in a non-symmetric contour of the diaphragm walls.

Abstract: Roller bearings, and struts and gas turbine engines using such bearings are provided. In this regard, a representative roller bearing for a gas turbine engine includes: a roller having a rolling surface and an end; a race having a flange and defining a raceway, the raceway terminating at the flange, the raceway being operative to receive the roller such that the rolling surface of the roller engages in rolling contact with the raceway; and a hard coating applied to the flange such that the end of the roller engages in sliding contact with the coating.