Electrohydraulic control device for a drive train of a machine

摘要

An electrohydraulic control device for a drive train of a machine is disclosed. The drive train includes an engine, a transmission, and a torque converter having a rotating housing. The torque converter is drivingly connected between the engine and the transmission. The torque converter also includes an impeller element. An impeller clutch connects the impeller element to the rotating housing. An impeller clutch electrohydraulic valve produces fluid flow to the impeller clutch to controllably engage and disengage the impeller clutch. A torque converter speed sensor senses the output speed of the torque converter and responsively produces a torque converter speed signal. A electronic device receives the measured torque converter speed signal, determines a desired torque convertor speed signal, produces an error speed signal in response to a difference between the measured and desired torque converter speed signals, and controllably actuates the electrohydraulic valve to cause the speed error signal to approach zero.