To improve easiness to get alongside the quay by accurately stopping a body.

When spools 58, 59 are rotated by an electric motor 39 driven in linkage with the operation of an operation lever 32 and a clutch cable 66 is moved in one direction with the friction force of a clutch cable 66, when fastened, wound on the spool 58 with the operation of the operation lever 32 in one direction, a reverse bucket 36 is oscillated downward via a stroke enlarging member 60 and a reverse cable 37. When the clutch cable 67 is moved to the other direction with the friction force of a clutch cable 67, when fastened, wound on the spools 58, 59 with the operation of the operation lever 32 in the other direction, the reverse bucket 36 is oscillated upward via the stroke enlarging member 60 and the reverse cable 37.