| 摘要 |
PROBLEM TO BE SOLVED: To prevent that an object exceeds an allowable stop position, and falls at a free fall of the object even if a failure occurs at an electric system which reaches an electric motor from a regenerative power consumption part, in an electric winch device of a crane having a regeneration function.SOLUTION: An electric winch device comprises: a necessary brake force derivation part which drives a necessary brake force for stopping an object 102 which freely falls at an allowable stop height h; a brake force decision part which decides a first brake force which is born by a brake device 24 out of an operation brake force corresponding to an operation amount of a pedal 28a, and a second brake force born by regenerative brake; and a control part which makes a drum 12 impart the first brake force decided by the brake force decision part to the brake device 24. When the operation brake force is not smaller than the necessary brake force when stopping the object 102 which freely falls, the brake force decision part decides the first brake force to a prescribed brake force which is not smaller than the necessary brake force.SELECTED DRAWING: Figure 1 |
