PURPOSE: To surely suck a substance in simple structure by connecting an air intake tube that communicates with a sucker composed of an elastic member, with an opening/closing valve, and by providing a controller that opens and closes the opening/closing valve by detecting deformation of the sucker when pressed on the substance to be adsorbed.

CONSTITUTION: By means of a controller 17, one edge of an air intake tube is opened in the air with an opening/closing valve 12 opened, while a sucker 10 starts to descend by a vertical moving system 13 until it adheres to sheet material S. The sucker 10 descends further until it is pushed by the substance S and is deformed flat, and when it reaches a predetermined state of deformation, the edge of an actuator 16 touches the substance S, and a signal is sent from a switch 15 to the controller 17, which closes the opening/closing valve 12 and stops the actuation of the vertical moving system 13 temporarily. The sucker 10 is then lifted up by the system 13, and, by means of the elasticity of the sucker 10 trying to be restored, the inside of the air intake tube 11 becomes the state of negative pressure, and the substance S is thus attracted by the sucker. When the substances S is dropped from the sucker 10, the controller 17 releases the opening/closing valve 12.