Twin drum cable winch for recovery of tree trunks in forestry operations has tension control systems to prevent parting of cable

摘要

A friction drive coupling (6) is placed between the drums (2) and the drive shaft (9), driven by a motor (4) and gearbox (5). The torque limit of the friction drive is adjustable according to the loading and the effective drum diameter, which changes with the amount of cable wound. The control system includes an ultrasonic sensor (14) and a microprocessor (15).