| 摘要 |
<p>A novel axial flow pump with a tube (Tu) attached to the impeller (R) and extending from the impeller eye (O) to the pump flange to improve pump tightness, and comprising an internal Archimedes' spiral with a hollow centre (a helical surface with a constant-angle director cone) providing mechanical pre-whirl of the liquid before it reaches the impeller eye (O°), said spiral being calculated in such a way that the pump impeller (R) is 'saturated'. The tube (Tu) may include an extension forming the electric motor shaft to provide a unitary motor pump in which the liquid cools the tube (Tu) and the motor rotor (Ro).</p> |
