A priming pump may include a housing; an inlet passageway inside of the housing; an outlet passageway inside of the housing; a divider, inside of the housing, separating the inlet passageway and the outlet passageway; a connecting passageway through the divider in fluid communication with the inlet passageway and the outlet passageway; a valve, disposed in the connecting passageway, configured for one-way fluid flow from the inlet passageway to the outlet passageway; a rotary pump, inside of the housing, having an inlet in fluid communication with the inlet passageway and an outlet in fluid communication with the outlet passageway; and a shaft connected to the rotary pump and extending through the housing, the shaft configured for rotation by an external driving mechanism.

The hydraulic injection system (100) with cam comprises an injection valve (50) housed in a tubular injection nozzle (54), a gap being formed between a valve stem (51) of said valve (50) and the inner surface of the tubular injection nozzle (54) to allow an injectable fluid (58) coming from pressurizing means (10) to flow, while a receiver piston (62) fixed with respect to said valve (50) receives on the one hand the pressure of the injectable fluid (58) to hold said valve (50) closed, and on the other hand, the pressure of a hydraulic fluid (60) to open said valve (50), an injection cam (67) being capable to move said receiver piston (62) via an emitter piston (69) and said hydraulic fluid (60).

The hydraulic injection system (100) with cam comprises an injection valve (50) housed in a tubular injection nozzle (54), a gap being formed between a valve stem (51) of said valve (50) and the inner surface of the tubular injection nozzle (54) to allow an injectable fluid (58) coming from pressurizing means (10) to flow, while a receiver piston (62) fixed with respect to said valve (50) receives on the one hand the pressure of the injectable fluid (58) to hold said valve (50) closed, and on the other hand, the pressure of a hydraulic fluid (60) to open said valve (50), an injection cam (67) being capable to move said receiver piston (62) via an emitter piston (69) and said hydraulic fluid (60).

An inner gear includes: sliding surface parts that are provided annularly at an outer peripheral part including a plurality of outer teeth on both sides of the inner gear in its axial direction and that slide on a pump housing; recessed parts that are respectively provided radially inward of the sliding surface parts to respectively form fuel chambers, into which fuel flows, between the recessed parts and the pump housing; and a communication hole that communicates between the recessed parts. The inner gear further includes an inclined surface part that is provided at an edge portion of a communicating edge portion on a rotation advance side of the inner gear, to avoid an adjacent part adjacent to an inner peripheral edge portion of each of the sliding surface parts and that is inclined further toward a rear side in a direction to a central part of the communication hole.

An inner gear includes: sliding surface parts that are provided annularly at an outer peripheral part including a plurality of outer teeth on both sides of the inner gear in its axial direction and that slide on a pump housing; recessed parts that are respectively provided radially inward of the sliding surface parts to respectively form fuel chambers, into which fuel flows, between the recessed parts and the pump housing; and a communication hole that communicates between the recessed parts. The inner gear further includes an inclined surface part that is provided at an edge portion of a communicating edge portion on a rotation advance side of the inner gear, to avoid an adjacent part adjacent to an inner peripheral edge portion of each of the sliding surface parts and that is inclined further toward a rear side in a direction to a central part of the communication hole.

A method for operating an electronically commutated fuel pump with an upstream fuel pump electronics unit of a motor vehicle, wherein the fuel pump is operated at a predefined speed, the method includes detecting a speed irregularity of the electronically commutated fuel pump, the speed irregularity being determined by examining the synchronicity between rotary field and rotor of the fuel pump, and switching over the speed of the electronically commutated fuel pump to a higher speed value than the predefined speed until a stable operation of the fuel pump without loss of synchronicity between rotary field and rotor of the fuel pump is achieved, the switchover of the fuel pump to the higher speed is performed by a predefined speed jump or is performed at predefined speed steps, the speed being increased until stable operation of the fuel pump is achieved.

A method for operating an electronically commutated fuel pump with an upstream fuel pump electronics unit of a motor vehicle, wherein the fuel pump is operated at a predefined speed, the method includes detecting a speed irregularity of the electronically commutated fuel pump, the speed irregularity being determined by examining the synchronicity between rotary field and rotor of the fuel pump, and switching over the speed of the electronically commutated fuel pump to a higher speed value than the predefined speed until a stable operation of the fuel pump without loss of synchronicity between rotary field and rotor of the fuel pump is achieved, the switchover of the fuel pump to the higher speed is performed by a predefined speed jump or is performed at predefined speed steps, the speed being increased until stable operation of the fuel pump is achieved.

A fluid pump includes an inlet plate with an inlet; an outlet plate, the outlet plate having an outlet plate outlet passage; an outlet; an electric motor having a shaft which rotates; a pumping element coupled to the shaft such that rotation of the pumping element by the shaft causes fluid to be pumped from the inlet to the outlet, the inlet plate interfacing with the pumping element in an inlet sealing surface interface and the outlet plate interfacing with the pumping element in an outlet sealing surface interface; a purge passage which receives fluid from the outlet plate outlet passage, the purge passage being in fluid communication with the inlet sealing surface interface and the outlet sealing surface interface; and a filter downstream of the outlet plate outlet passage which filters fluid that passes through the purge passage prior to reaching the inlet and outlet sealing surface interfaces.

A fluid pump includes an inlet plate with an inlet; an outlet plate, the outlet plate having an outlet plate outlet passage; an outlet; an electric motor having a shaft which rotates; a pumping element coupled to the shaft such that rotation of the pumping element by the shaft causes fluid to be pumped from the inlet to the outlet, the inlet plate interfacing with the pumping element in an inlet sealing surface interface and the outlet plate interfacing with the pumping element in an outlet sealing surface interface; a purge passage which receives fluid from the outlet plate outlet passage, the purge passage being in fluid communication with the inlet sealing surface interface and the outlet sealing surface interface; and a filter downstream of the outlet plate outlet passage which filters fluid that passes through the purge passage prior to reaching the inlet and outlet sealing surface interfaces.

The disclosed lift pump employs a unique arrangement of conductive studs to transmit the three phases of motor power from the control board to the brushless motor. The conductive studs penetrate the wall of the motor/pump enclosure, which is otherwise non-conductive. The conductive studs are intentionally larger than needed to transmit the current used by the motor, and are arranged in thermal contact with heat conductive portions of the motor control board to transmit heat from the control board into the motor/pump enclosure where heat is transmitted to fuel passing through the assembly. An additional center heat sink is situated in a position aligned with heat generating capacitors that are part of the motor drive circuitry on the motor control board.