| 摘要 |
PROBLEM TO BE SOLVED: To greatly suppress the occurrence of a submerged vortex and an air intake vortex by a simple configuration without deteriorating a drainage efficiency. SOLUTION: A vertical shaft pump includes: a lifting pipe 11; and a main shaft 15 extending inside the lifting pipe 11 and having an impeller 19 fixed on a lower end side thereof. The vertical shaft pump further includes: a tubular outside flared part 24 provided on a lower side of the impeller 19 on the lower end side of the lifting pipe 11; a tubular inside flared part 26 provided inside the outside flared part 24 and extending downward while being spaced apart a predetermined distance from the outside flared part 24, in which a lower end opening 26c thereof is positioned on a lower side relative to a lower end opening 24c of the outside flared part 24; and three of more vortex flow prevention ribs 31 provided inside the inside flared part 26 and projecting downward from the lower end opening 26c of the inside flared part 26. COPYRIGHT: (C)2013,JPO&INPIT |
