Patent ID: 7024964
Filing Date: 2006-04-11
Classification: E02F,F15B,Y10T

Abstract:
1. A hydraulic drive device utilizing an electric motor comprising: an electric motor; a first rotation transmission device that is connected to an output shaft of said electric motor and performs speed increasing function; a hydraulic pump driven by rotation of an output shaft of said first rotation transmission device; a hydraulic motor in which oil from said hydraulic pump is supplied through an operation-switching valve; a second rotation transmission device that is connected to an output shaft of said hydraulic motor and performs speed-increasing function; and a drive output shaft disposed on the output side of said second rotation transmission device, wherein said rotation transmission device comprises an input shaft; a rotating body that is connected to said input shaft, acts by itself as a flywheel, and on the output side of which an internal gear is formed; and a gear mechanism for transmitting rotation of said rotating body to a drive output shaft disposed on an output shaft gear by allowing counter gears to mesh with said internal gear and the output shaft gear to mesh with these counter gears; wherein a protrusion is formed on either the outer circumference of said rotating body or a stationary frame, and a recess surrounding said protrusion is formed on the other.