An electric fuel pump includes a housing having an oil inlet and an oil outlet, an impeller, a stator unit mounted in the housing and including a stator and a starter terminal set connected to the stator, a packaging adhesive encapsulating the stator and the starter terminal set to create an oil guide passage in communication between the oil inlet and the oil outlet, and a rotor unit mounted in the housing and including a rotor rotatably mounted in the stator and a rotating shaft mounted in the rotor and connected with the impeller. When the stator unit is electrically conducted, the rotor unit drives the impeller to draw a fuel oil into the oil guide passage. When the fuel oil goes through the oil guide passage, the stator and the starter terminal set are well protected by the packaging adhesive and prohibited from contacting the fuel oil.

An impeller for a fluid pump includes a central hub, an inner portion located adjacent to the central hub and an outer portion, the outer partially being radially outward from the inner portion. An array of vanes is located between the inner portion and the outer portion. At least one slot is formed within the outer portion. The at least one slot faces an angle of rotation of the impeller.

A sealing ring gland receives a sealing ring. The sealing ring gland includes an inner wall surface which seals against an inner periphery of the sealing ring. An outer wall surface is radially offset from the inner wall surface and seals against an outer periphery of the sealing ring. The sealing ring is axially compressed between an upper wall surface and a lower wall surface of the sealing ring gland. At least one of the upper wall surface and the lower wall surface includes an expansion volume which provides space for the sealing ring to expand upon swelling of the sealing ring.

A sealing ring gland receives a sealing ring. The sealing ring gland includes an inner wall surface which seals against an inner periphery of the sealing ring. An outer wall surface is radially offset from the inner wall surface and seals against an outer periphery of the sealing ring. The sealing ring is axially compressed between an upper wall surface and a lower wall surface of the sealing ring gland. At least one of the upper wall surface and the lower wall surface includes an expansion volume which provides space for the sealing ring to expand upon swelling of the sealing ring.

An engine fuel or pump system includes a centrifugal pump having an impeller for imparting energy to an associated fluid for an associated downstream engine fuel system. A regenerative start stage is in selective fluid communication with the pump. And ejector includes an inlet that communicates with the pump outlet and an outlet that communicates with the pump inlet. Further, a regulator valve is interposed between the pump outlet and the regenerative start stage that selectively regulates associated flow from the regenerative start stage. The associated method include directing flow from the centrifugal pump to a regenerative start stage in order to supply an associated downstream flow circuit. During low speed starting, a portion of the flow from the regenerative start stage is provided to an ejector that recirculates to an inlet of the centrifugal pump. Once the centrifugal pump provides a predetermined level of at least one of the flow and pressure requirements of the associated flow circuit, the method includes terminating flow from the regenerative start stage.

An electric fuel pump includes a housing having an oil inlet and an oil outlet, an impeller, a stator unit mounted in the housing and including a stator and a starter terminal set connected to the stator, a packaging adhesive encapsulating the stator and the starter terminal set to create an oil guide passage in communication between the oil inlet and the oil outlet, and a rotor unit mounted in the housing and including a rotor rotatably mounted in the stator and a rotating shaft mounted in the rotor and connected with the impeller. When the stator unit is electrically conducted, the rotor unit drives the impeller to draw a fuel oil into the oil guide passage. When the fuel oil goes through the oil guide passage, the stator and the starter terminal set are well protected by the packaging adhesive and prohibited from contacting the fuel oil.

A fluid pump includes an inlet for introducing fluid into the fluid pump and an outlet for discharging the fluid from the fluid pump. A motor is included having an armature which rotates about an axis. The motor also has a stator which circumferentially surrounds the armature such that a fluid passage is defined radially between the armature and stator through which the fluid flows from the inlet to the outlet. A pumping arrangement is rotated by the armature and pumps the fluid from the inlet to the outlet. A flow impedance member extends axially in the fluid passage which impedes circumferential flow of the fluid within the fluid passage, thereby generating a pressure gradient circumferentially within the fluid passage which applies a lateral force to the armature.

An engine fuel or pump system includes a centrifugal pump having an impeller for imparting energy to an associated fluid for an associated downstream engine fuel system. A regenerative start stage is in selective fluid communication with the pump. And ejector includes an inlet that communicates with the pump outlet and an outlet that communicates with the pump inlet. Further, a regulator valve is interposed between the pump outlet and the regenerative start stage that selectively regulates associated flow from the regenerative start stage. The associated method include directing flow from the centrifugal pump to a regenerative start stage in order to supply an associated downstream flow circuit. During low speed starting, a portion of the flow from the regenerative start stage is provided to an ejector that recirculates to an inlet of the centrifugal pump. Once the centrifugal pump provides a predetermined level of at least one of the flow and pressure requirements of the associated flow circuit, the method includes terminating flow from the regenerative start stage.

A fuel pump includes a pump cover at one end portion of the housing, a cover end at the other end portion of the housing, a bearing supported by the cover end and rotatably supporting an end portion of the shaft on the cover end-side. The cover end includes a base part that covers the other end portion, a discharge part that is connected to the base part, a bearing accommodating part which is formed such that a cross-section of the bearing accommodating part perpendicular to a rotation axis of the shaft has an annular shape and which includes an accommodating space accommodating the bearing, and a connection part that connects together the base part and the bearing accommodating part. A length of the connection part is shorter than a length of the base part and a length of the bearing accommodating part, in a direction of the rotation axis.

A fuel delivery pump for delivering fuel, having an electric motor and having a pump impeller that is driven by means of the electric motor, wherein the pump impeller is connected by means of a shaft to a rotor of the electric motor such that a rotational movement of the rotor is transmitted via the shaft to the pump impeller, wherein the shaft is mounted by means of an axial bearing in an axial direction and/or by means of a radial bearing in a radial direction relative to a pump stage in which the pump impeller is arranged, wherein an electrical insulation element is arranged between the axial bearing and the pump stage, and/or an electrical insulation element is arranged between the radial bearing and the pump stage.