Circumferential flow type liquid pump

摘要

A circumferential flow type liquid pump includes an impeller with vanes on its outer periphery, and a pump casing assembly defining an arcuate elongated pump flow path along the outer periphery of the impeller and a suction inlet and a discharge outlet at both ends of the pump flow path. The pump casing assembly includes a radially-extending gas venting path which is opened in the inner periphery of the pump flow path near the impeller and separated by a step from the bottom of the pump flow path, and a through-hole much larger in sectional area than the gas venting path, through which the gas venting path is communicated with the outside of the pump casing assembly. Bubbles formed by vaporization of the fuel in the pump flow path are positively discharged from the pump casing assembly, and no vapor locking is caused.