Hydraulic power unit for an elevator drive

摘要

A vertically oriented hydraulic power unit (40) for an elevator drive includes an outer tank (50) for drive fluid and an inner tank (88) for fluid used to submerge and cool a motor, the fluids being exchangeable to maintain temperature in the inner tank (88) at or below a specified maximum temperature. Oil returning from an elevator piston is fed into said inner tank (88) to keep the inner tank (88) sufficiently cool. <IMAGE>