Abstract: A crane system for carrying a load while suspending it from a portal-shaped body frame via wire ropes includes first and second wire ropes on both sides, in a right-and-left direction, of an upper portion of the body frame for fixing the suspended load, and means for taking up and paying out the first and second wire ropes. The system also includes means for winding the first and second wire ropes in opposite directions, or winding them in the same direction. The first and second wire ropes may be looped together with the means of taking up and paying out the wire ropes. Connection points or sheaves may be provided on the suspended load. It is also permissible to route the first and second wire ropes parallel to each other. Further, the above takeup and payout means may be in a tapered drum form.

Abstract: A crane apparatus is disclosed. A hoisting accessory is traversed by rotating rotating drums by driving of a traversing motor to take up or pay out wire ropes. Continuously variable transmissions are provided for changing rotational speeds of the rotating drums. A control device controls the continuously variable transmissions in a gear changing manner so that forces imposed on the drums by the wire ropes will be balanced. Thus, torques acting on the pair of drums are canceled out in all areas in which the hoisting accessory moves, whereby the capacity of the drive motor can be reduced.

Abstract: A crane apparatus is disclosed. First traverser wire ropes are connected to a right connecting portion of a traverser, while second traverser wire ropes are connected to a left connecting portion of the traverser. First hoisting accessory wire ropes are passed over a right rope pulley via the traverser, and then connected to the traverser, while second hoisting accessory wire ropes are passed over a left rope pulley via the traverser, and then connected to the traverser. A hoisting accessory is suspended from the right and left rope pulleys. The crane apparatus enlarges the traversing range of the hoisting accessory, and increases work efficiency, without becoming upsized.