Variable Speed Fan Drive

摘要

A variable fan drive (10) for a vehicle powered by an internal combustion engine (13) is provided. A drive side assembly (12) utilizes a hydraulic actuator to actuate a variable sheave assembly (20). The variable sheave assembly (20) drives a sheave assembly (22) of a driven side assembly (14) by way of a v-belt (18). The hydraulic actuator has a piston (114) coupled to the variable sheave assembly (20). The piston (114) is hydraulically translated by pressurized engine oil from the internal combustion engine (13). An electronically controlled solenoid valve (124) controlled by an engine or vehicle controller selectively controls the flow of engine oil for piston actuation. Thus the speed of the fan (16) can be controlled based on various engine or vehicle operating parameters.