To hold each object in suction certainly regardless of the plane shape of the object to be held with suction.

If a communication hole 57 is opened upon applying the oversurface of each object only to a left-hand opening 46 so as to block it, a left-hand recess 45 and a lower chamber 42b are put immediately in negative pressure simultaneously, so that a valve element 50 does not close a suction port 49, and the object comes in tight attachment to a resilient piece 47. On the other hand, the right-hand opening 46 remains unclosed, and the suction port 49 mating with the right-hand opening 46 is closed automatically by the valve element 50 sucked toward the suction port 49 because inside the lower chamber 42b is put in negative pressure.