Drive control apparatus of cooling fan used in hydraulic powered machine e.g. construction machinery, controls capacity of hydraulic motor and pump based on difference between actual and target values of fan speed

摘要

A pump (2) supplies hydraulic oil to a motor (7) which drives a circulating water cooling fan (8). Target fan speed is set up corresponding to temperature Tc' of circulating water. The capacity of pump and motor are controlled so that speed N' of the fan becomes the target fan speed.