Abstract: A planetary gear transmission has two or more planetary gear sets in the gear train. Each planetary gear set comprises a sun gear mounted on a sun shaft with the sun gear engaging a plurality of planet gears mounted on a planet gear carrier with the plurality of planet gears engaging a ring gear mounted on the transmission housing. Each gear of the planetary gear transmission is a helical cut gear. Sun gears and/or ring gears are mounted for axial movement with respect to the transmission. Thrust imbalances on the sun gears and/or ring gears resulting from uneven loading and the helical cut result in sun gears and/or ring gears moving in the axial direction to eliminate the thrust imbalances and thereby resulting in equal loading or power sharing amongst the planetary gear sets.

Abstract: In a gear transmission, pairs of helical gears are rotatably mounted on a drive shaft for axial movement on the drive shaft. The pairs of helical gears mounted on the drive shaft engage corresponding pairs of helical gears rotatably mounted on a driven shaft for axial movement on the driven shaft. Retainer members are located adjacent each end of at least one of the shafts to restrict axial movement by helical gears caused by axial separation between pairs of helical gears resulting from commencement of rotation of the drive shaft.

Abstract: A fluid recovery system for use in a relatively deep down hole environment in which a power source at the surface drives a high capacity pump through a power transmission disposed in proximity to the pump in the down hole environment and which power transmission drives the pump at a relatively high speed relative to the speed of the power source.