PURPOSE: To make a rod or the like so as not to have protruded from an apparatus mounting part with the movement in the longitudinal direction of the rod by extending or contracting and slackening the rod properly with the movement of a flow pipe being housed in the inner part in the longitudinal direction.

CONSTITUTION: A suction means 11 is attached to one end of a flow pipe 13, and this flow pipe 13 is shifted in the longitudinal direction of the flow pipe 23, whereby a position of the suction means 11 is adjusted. Since the air flow pipe 13 is flexible in structure, it is recommended that this pipe 13 is prevented from being projected to the upper part of an apparatus mounting part by means of slackening the flow pipe 13. Moreover, as for a rod 17, one end is attached to the apparatus mounting part and the other end to one end of the flow pipe 13, respectively, and the flow pipe 13 housed in the inner part extends or contracts with its movement in the longitudinal direction. Since the flow pipe 13 is flexible and the rod 17 is extended or contracted, a floor space is made reducible. Negative pressure for attracting a conveyed work is generable when a flow of air is produced by suction or exhaust of the air.