HYDRAULIC HYBRID SWING DRIVE SYSTEM FOR EXCAVATORS

摘要

Swing drive systems for excavators utilize prime movers mechanically connected to the first hydraulic pump / motor and second hydraulic pumps / motors mechanically connected to the swing mechanism. The system includes a hydraulic fluid reservoir, a hydraulic accumulator, a hydraulic circuit connecting the first hydraulic pump / motor and the second hydraulic pump / motor. The system is operable in one mode in which the second hydraulic pump / motor acts as a pump to retard the movement of the swing mechanism and the pressurized hydraulic fluid from the second hydraulic pump / motor is pumped into the hydraulic accumulator. Do. The system is operable in another mode to assist the prime mover when pressurized hydraulic fluid from the hydraulic accumulator drives the hydraulic consumer including the pivot drive.