A hook device includes a central shaft which extends in a first direction, and a first locking portion and a second locking portion which are disposed such that the central shaft is interposed therebetween, in a second direction orthogonal to the first direction. The first locking portion and the second locking portion are connected to the central shaft in a state where the first locking portion and the second locking portion are not rotatable independently around an axis extending in the first direction and are rotatable around an axis extending in a third direction different from the first direction and the second direction.
HOOK DEVICE AND CRANE
2020-01-30
Patent
Electronic Resource
English