TAKE-UP DEVICE FOR CRANE

PROBLEM TO BE SOLVED: To prevent excessive input torque from being transmitted to the component parts of a winch drum. SOLUTION: A speed reducer 5 is connected with a prime mover 2 via a wet type multiple disc clutch 3 and a torque converter 4. A gear train 7 is connected with the output shaft of the speed reducer 5, and a boom derricking winch 11, a main winch 12 add an auxiliary winch 13 are connected with the respective output shafts 8, 9 and 10 of the gear train 7 via friction clutches 14, 15 and 16. And an electromagnetic proportion valve (not indicated in the figure) for adjusting clutch combining force is interposed to a hydraulic circuit driving the wet type multiple disc clutch 3. And input torque in response to the revolutions of the winch is operated by a controller 17, so that the electromagnetic proportion valve is thereby controlled based on a duty ratio corresponding to the input torque.