In one exemplary embodiment, an epicyclic gear train for a turbine engine includes a first shaft that is rotatable about an axis. A ring gear includes first and second portions each having an inner periphery with teeth. The first and second portions are secured to one another at a radial interface. At least one of the first and second portions includes a flange that extends radially outward. The flange is fixed to the first shaft in an axial direction by a fastening element. A carrier supports star gears that mesh with the ring gear. A sun gear meshes with the star gears and is coupled to a second shaft.

Systems and methods in accordance with embodiments of the invention implement copper-based materials in applications where resistance to wear is desired. In one embodiment, a wear-resistant gear includes a gear defined by a rotatable body having teeth disposed on an outer surface of the rotatable body, where the gear body is formed at least in part from a material including copper and X, where X is one of zirconium, titanium, hafnium, rutherfordium, and mixtures thereof and where the atomic ratio of copper to X is approximately between 2:3 and 3:2.

An epicyclic gear train for a turbine engine includes a gutter with an annular channel. A rotating structure includes a ring gear that has an aperture that is axially aligned with the annular channel. Axially spaced apart walls extend radially outward relative to the rotating structure to define a passageway. The passageway is arranged radially between and axially aligned with the aperture and the annular channel. The walls are configured to inhibit an axial flow of an oil passing from the aperture toward the annular channel.

A cassette for a bicycle may include a plurality of sprocket portions joined together into a single unit. The cassette may include a cavity formed in the large end of the cassette. A related manufacturing method may include joining a first generally planar sprocket portion having a plurality of connector portions extending transverse to the plane of the first sprocket portion, to a second generally planar sprocket portion, e.g., by fusing at least one of the connector portions to the second sprocket portion.

A sprocket assembly is provided. The assembly includes a sprocket frame having a central body and a first ledge portion body. The first ledge portion has a first aperture extending therethrough. The assembly further includes a first removable tooth having a first tip portion, first and second landing portions, and a first extension portion. The first tip portion has first and second ends. The first extension portion extends from the second end and has an aperture extending therethrough. The assembly further includes a first bolt extending through the first aperture in the first ledge portion and the aperture in the first extension portion to removably couple the first extension portion to the first ledge portion.

A bidirectional gear set includes a male bidirectional gear component having an array of addendum teeth and a female bidirectional gear component having an array of dedendum sockets, wherein each dedendum socket has a full boundary edge around an open end thereof. One or both of the male and female gear components may have a circular cross sectional geometry, or one may have a non-circular cross sectional geometry. The non-circular cross sectional geometry may be a flat sheet or a sheet with surface contour. In an intermeshed state, neither the male nor the female component can slide relative to the other regardless of whether the male and female components are arranged in a parallel or perpendicular orientation. A method of making a bidirectional gear set is disclosed.

This invention addresses the problem of providing a press-fit structure and a press-fit method capable of improving the durability of a gear which press-fits into a ring part. As such, the embodiment of this invention is that, while one end side in the central axis direction of the ring gear abuts against a protrusion formed protruding on the outer side of the radial direction of the ring part from the outer circumferential surface of the ring of the ring part, and wherein the press-fit structure press-fits the inner circumferential surface of the gear into the outer circumferential surface of the ring part, when the inner circumferential surface of the gear is press-fitted into the outer circumferential surface of the ring part, there is a tensile strength reduction mechanism reducing the tensile strength generated in the lower portion of the gear teeth in at least the position of the aforementioned end side of the gear.

[Task] To provide a method that makes it possible to easily, inexpensively and accurately manufacture a machined part with a simple configuration and an excellent strength. [Means for Solution] In a method for manufacturing a machined part according to the invention, a dislocation is partially introduced (S3), through shot peening, only into a surface layer of a raw material 1 in a region 1a to be machined, graphite is partially deposited (S4), through heating, only in the surface layer of the region 1a to be machined, and then, the surface layer of the region 1a where graphite is deposited is removed, through machining (S5), only by an amount corresponding to a working margin 1c, thereby manufacturing a machined part 1.

Apparatus and associated methods relate to a unitary ring gear-flange body (URGFB). In an illustrative example, the flange body may be spin-formed and may, for example, include a riser body extending substantially parallel to a longitudinal axis and a flange extending substantially radially outward from the riser body. To the riser body may, for example, be welded a ring gear to form a unitary assembly, the ring gear having an axis of revolution aligned with the longitudinal axis. A continuous coating may, for example, be applied to at least a selected portion of a surface of the unitary assembly. Various embodiments may advantageously provide a cost-efficient, weight-efficient, and/or time-efficient unitary body which may, for example, be coupled to machinery to provide a shaftless torque-transmitter.