Gathering unit control apparatus

Abstract

A control apparatus is provided for controlling a gathering unit mounted on a forage harvester for vertical articulative movement about a transverse axis thereon, the control apparatus including a main lever pivotally mounted on the forage harvester frame and operatively attached by a tension apparatus to the gathering unit, a lifting apparatus interconnecting the frame and main lever through a lost motion connection for selectively engaging the main lever to lift the gathering unit, a floatation spring lever having a first pivotal connection and a second detachable connection with the main lever, and a floatation spring assembly interconnecting the spring lever and the frame, the floatation spring assembly counterbalancing a portion of the weight of the gathering unit when the detachable connection between the spring lever and the main lever is attached and being ineffective when the detachable connection is detached. The tension apparatus comprises a single tension member having its ends operatively connected to the gathering unit on each side of the crop inlet and its medial portion operatively engaging a pulley attached to the main lever in order to equalize the loading on the lifting apparatus.