DIRECT-COUPLED CLUTCH CONTROLLER FOR FLUID TRANSMISSION DEVICE

摘要

PURPOSE:To simplify the structure of hydraulic circuit by controlling the direct- coupled clutch of fluid transmission device by means of first spool valve for switching between hydraulic source and drain path and second spool valve for regulating the changing rate of differential pressure. CONSTITUTION:A direct-coupled clutch 2 of fluid transmission device is controlled by first spool valve 6 for switching between hydraulic source 4 and drain oil path to produce differential pressure, second spool valve 7 provided in the drain path to regulate the discharge pressure rate thus to regulate the changing rate of differential pressure and solenoid valve S1 for controlling the first spool valve 6 under first duty ratio region while controlling second spool valve 7 under second duty ratio region. Consequently, only one control means is required to simplify the structure of hydraulic circuit while to facilitate the control resulting in precise control of direct-coupled clutch with correspondence to the travel conditions and smooth engaging/disengaging of direct-coupled clutch.