PURPOSE: Simultaneous as seeing to it that high precision can be maintained by making the movable piece that constitutes the drive device be able to move up and down vertically with the result that no eccentricity takes place due to the partial attrition of the bearing, by making the diaphragm one of such a type as is annularly driven, to make the whole apparatus compact and thus to attain a high efficiency

CONSTITUTION: If electro-magnetic coil 6 inserted into yoke 4 is connected to alternative current power source, movable piece 7 installed to be axially freely slidable inside yokes 4, 5 and formed by setting magnetic pole piece 9 to the both ends of permanent magnet 8 magnetized axially by means of axial-directional alternating fields, alternately reciprocates in the axial, that is to say, vertical direction and drives diaphragm 13 which is in a combined condition via shaft 10. Therefore, by virtue of the capacity fluctuations of the chamber 24, the fluid attracted into the attraction room 20 via link ports 30, 22 and 15 from inhalation opening 29, is intermittently, exhausted from exhaust port 23 via exhaustion room 21 by way of inhalation valve 16 and exhause valve 17. In this case, the fluid is purified by filter 28 and circulates back to the drive chamber 25.