PURPOSE: To simplify the constitution so as to enable failure prevention and remote control by providing a roller capable of rocking between branched passages at a branchpoint of a ball transfer passage.

CONSTITUTION: A ball 12 moves inside a transfer passage 10a and reaches a branchpoint. Then a branch device 14 is located at a position of a line segment 1 and the ball surely collides a roll 20. At that time, the roller 20 is rotated in the specified direction by a motor not shown in the figure. For example, if the roller 20 is rotated anticlockwise, a rod 18 rotates clockwise to close a transfer passage 10b by the revolving force of the roller 20 and the reactive force of the ball and the ball 12 moves in the arrow B direction. If the roller 20 is rotated reversely, the ball 12 moves in the arrow C direction inside a branch passage 10b. By this constitution, the constitution becomes simple, the trouble is decreased and the remote control becomes possible.