Methods of repairing a torque converter that enable the continued use of a torque converter and result in a repaired torque converter with a higher-strength and more durable construction. In some examples, a backing ring can be replaced with a replacement backing ring that includes a spline ring for replacing the function of a cover spline ring. In some examples, a method of repairing a torque converter can be improved by providing a replacement backing ring with a radial protrusion for locating the backing ring on the cover, and a method of determining an axial location of the radial protrusion.

A gear drive device includes a first gear, a second gear that meshes with the first gear to allow torque transmission, and a biasing member that applies rotational torque in one direction to the first gear or the second gear. The first gear and the second gear are brought into contact at a contacting tooth surface thereof by the biasing member. At least one of the first gear and the second gear includes a non-contacting tooth surface that is on an opposite side of the contacting tooth surface and partially removed.

A gear train includes a first gear having teeth meshed with teeth of a second gear. Each tooth of the first gear includes a coast side and a drive side opposed to the coast side. The drive side has a pressure angle that is greater than that of the coast side. The gear train can be part of a powertrain system for a rotorcraft, and can replace a traditional gear train in a retrofit or new build. The first gear is a planet gear and the second gear is a ring gear wherein the planet gear and ring gear are in a planetary gear train configuration.

An output ring gear for use in an integrated drive generator has a gear body extending between a first end and a second end and having a disc extending radially outwardly. A boss extends from the disc toward the second end. There are outer gear teeth outwardly of an outer diameter of the disc. There are inner gear teeth inwardly of an inner surface of the disc. The outer and inner gear teeth have a unique gear tooth profile with roll angles A, B, C, and D. An integrated drive generator and a method are also disclosed.

A gear train mechanism of a timepiece is formed by a gear having an involute tooth profile, which is easily manufactured, and a pinion that meshes with the gear. In order to reduce a fluctuation in torque to be transmitted, a gear train mechanism of a timepiece includes a gear including a tooth having a tooth profile of an involute curve and a pinion including a tooth meshing with the tooth of the gear to transmit and receive a torque, wherein the torque to be transmitted from the gear to the pinion is substantially constant at least in a part of a first half of a meshing period of the gear and the pinion.

A gearbox assembly includes a first gear and a second gear. The first gear includes a plurality of first gear teeth. The second gear includes a plurality of second gear teeth. The plurality of first gear teeth and the plurality of second gear teeth mesh with each other as the first gear and the second gear rotate. A profile shape of at least one first gear tooth of the first gear is characterized by a total profile modification between 66 micrometers and 120 micrometers.

An accessory drive gear for use in the integrated drive generator includes a gear body extending between a first end and a second end and having a plurality of gear teeth at a radially outer surface adjacent the first end, and the gear teeth having a gear tooth profile, with roll angles A, B, C, and D, and the roll angle at A being between 17.0 and 18.5, the roll angle at B being between 20.0 and 21.5, the roll angle at C being between 29.5 and 31.0, and the roll angle at D being between 32.5 and 34.0. In addition, an integrated drive generator is disclosed as is a method of replacing an accessory drive gear in an integrated drive generator.

A gear device includes a first gear, a second gear, and a third gear. The second gear is constituted of first meshing teeth that mesh with teeth in a first row of teeth of the first gear, second meshing teeth that mesh with teeth in a second row of teeth of the first gear, third meshing teeth that mesh with teeth in a third row of teeth of the third gear, and fourth meshing teeth that mesh with teeth in a fourth row of teeth of the third gear. The helix directions of the first meshing teeth and the third meshing teeth are the same direction. The helix directions of the second meshing teeth and the fourth meshing teeth are the same direction.

A method of avoiding gear tooth interference in a planetary gear system includes designing and building a planetary gear system comprising a selected base pitch and tooth length for planet gears, breaking a rim of one of the planet gears, and verifying whether tooth tip interference occurs during operation of the planetary gear system.

A check method of worm gears includes the following steps: identification of a real profile (PR) of a worm gear to be checked; scanning of the real profile (PR) in such a way to obtain a measured profile (PM), filtering of the measured profile (PM) with a low pass filter in such a way to obtain a primary profile (PP), filtering of the primary profile (PP) with a high pass filter in such a way to obtain a surface analysis profile (SA), calculation of three parameters (SA.sub.3; SA.sub.q; SA.sub.p) from said surface analysis profile (SA) and comparison of the three parameters (SA.sub.3; SA.sub.q; SA.sub.p) with preset threshold values (TSa; TSq; TSp) in such a way to reject the worm gear when at least one of the parameters exceeds the corresponding threshold value.