| 摘要 |
<p>The invention provides an impeller for a circumferential current pump which does not generate a weld phenomenon and can make a structure of an injection molding metal mold simple. An impeller (2) for a circumferential current pump (1) is provided with a plurality of vane grooves (12) on an outer periphery of a synthetic resin disc-like member (8) rotated by a motor (3a), and is rotatably received with a substantially disc-like space (6) formed between a pump casing (4) and a pump cover (5). An axial hole (15) engaging with a drive shaft (21) of the motor (3a) is formed in a center portion of the disc-like member (8), and a pressure adjusting groove (17) open to both side surfaces (10, 11) of the disc-like member (8) is formed in the axial hole (15). An annular recess portion (18) for arranging a ring gate (20) for injection molding Is formed at a position a predetermined size apart from an outer peripheral side of the axial hole (15). The pressure adjusting groove (17) functions to keep a balance of a pressure applied to both side surfaces (10, 11) in the impeller (2). <IMAGE></p> |
