Circumferential flow pump

Abstract

A circumferential flow pump in which the quantity of swelling by alcohol or toluene contained in fuel, is curbed and an impeller thereof is prevented from locking is provided. A circumferential flow pump for feeding into an internal combustion engine, fuel from the fuel tank thereof includes an impeller, made of fiber-reinforced PPS, having a base portion fitted to a motor rotor, a vane portion provided outer-circumferentially on the base portion, and an outer ring portion provided outer-circumferentially on the vane portion; the vane portion is composed of a plurality of vanes arranged radially protruding straightly from the base portion and each vane includes a bend thereon; and furthermore, given that a projected area of the entire vane portion is S1, that of the ring portion, S2, that of the base portion, S3, when the impeller, is projected from a direction along a motor shaft of the motor rotor, the ratio of S3 to S1 is made to fall between 9:1 to 15:1, and the ratio of S2 to S1 is made to fall between 0.10:1 to 0.13:1.

Dependencies are inferred from the claim text.