PURPOSE: To prevent open separation between a spherical bearing and a bearing plate by providing a pressure member of pressing an impeller to a partitioning plate side along a rotary shaft with a pump chamber side magnet, in a pump of rotating the pump chamber side magnet by magnetic coupling to a drive side magnet.

CONSTITUTION: When a drive side magnet 29 is rotated by a motor 26, a pump chamber side magnet 33 is rotated by magnetic coupling to the drive side magnet 29, to rotate an impeller 32, and a fluid sucked from a flow inlet 37 is boosted to be delivered from a flow outlet 38. Here is fixed a support bearing 36 to a rotary shaft 35, to mount this bearing 36 movably in an axial direction in the flow inlet 37. A spring 41 is interposed between a lower flange part of the support bearing 36 and a holding part 39, to press energize downward the bearing 36 by tension of this spring. That is, a spherical bearing 31 is pressed to a bearing plate 30, and by pressing with the spring 41 and by attracting force of the magnets 29, 33, the impeller 32 is prevented from floating at pump inoperative time.