A DRIVING UNIT THAT COMPRIZES A HYDRAULIC MOTOR AND A REDUCTION GEAR

摘要

A driving unit is provided to decrease a size of the driving unit by integrating an output shaft of a hydraulic motor with an input shaft of a decelerator. Hydraulic motors are arranged in a fixed casing(11). A rotation casing(12) is rotatably supported by a shaft mount, which is inserted from one end of the fixed casing. An inner gear is included in the rotation casing. A sun gear(17) is attached to an output shaft, which is protruded from one end of the hydraulic motor. A planetary gear train is arranged between the sun gear and the inner gear and performs a deceleration process. At least one stage of the planetary gear train includes two planetary gears(20) and a planetary frame(19). The planetary gears are symmetrically arranged from an output shaft. The planetary frame supports the planetary gears at both ends of an axial direction. The planetary frame includes a pair of planar units and a pole. A portion of the pole is arranged along an outer periphery of the planar unit to be adjacent to the planetary gear.