Patent ID: 6311488
Filing Date: 2001-11-06
Classification: F01P,F16D

Abstract:
A cooling fan drive apparatus having a main hydraulic pump driven by a drive source; a hydraulic actuator actuated by supply of actuation pressure oil discharged from said main hydraulic pump, via a control valve; and a cooling fan for cooling said drive source or said actuation pressure oil, comprising:a variable-capacity dedicated fan drive hydraulic pump driven by said drive source;a hydraulic motor for turning said cooling fan, actuated by inflow through an inflow port of pressure oil discharged from said variable-capacity dedicated fan drive hydraulic pump;temperature detection means for detecting temperature of said drive source or of said actuation pressure oil;setting means for setting correlation between said temperature of said drive source or said actuation pressure oil and a target fan rotational speed for said cooling fan; andcapacity control means for controlling target fan rotational speed corresponding to temperature detected by said temperature detection means, in accordance with correlation set by said setting means, and varying the capacity of said variable-capacity dedicated fan drive hydraulic pump so that said cooling fan rotational speed becomes said target fan rotational speed.