Patent ID: 7946829

Claim:
A jet pump, which is adapted to be provided in a tank and through which a liquid flows, comprising: a jet nozzle including an injection port for injecting the liquid; a throat pipe including a throat passage, the throat pipe including a downstream side, wherein the liquid injected from the injection port flows into the throat passage, wherein: the liquid in the throat passage forms a liquid seal across a cross section of the throat passage to generate negative pressure, which introduces the liquid into the throat passage; and a cup in fluid communication with an open part of the downstream side of the throat pipe that holds liquid therein, wherein: the cup includes at least one collision wall surface that opposes the open part of the downstream side of the throat pipe; the at least one collision wall surface includes a top end and a lower end; a first distance from the top end to a plane, which is at the open part of the throat pipe and is perpendicular to an axis of the throat pipe, in a direction parallel to the axis, is smaller than a second distance from the lower end to the plane in the direction parallel to the axis; the axis is parallel to a bottom surface of the tank; and the jet pump is provided in the tank such that the throat passage extends in a direction of the axis of the throat pipe and such that the cup opens in a direction opposite from the bottom surface of the tank.