A pump body of a high pressure fuel pump defines a compression chamber in fluid communication with a first recess dug in a first outer face. A second recess is dug in a second outer face of the body. An inlet channel opens in a conduit extending between the first recess and the second recess.

A fuel supply device of an engine includes a primary pump suctioning fuel to discharge the fuel to a first pipeline, a secondary pump connected in series to the primary pump via the first pipeline, and suctioning the fuel from the primary pump to supply the fuel through a second pipeline to an engine side, a tank storing the fuel and accommodating the secondary pump, an outflow part causing part of the fuel flowing from the first pipeline through the secondary pump to the second pipeline in the tank to flow outward, a third pipeline returning, to a suction side of the primary pump, gas-liquid mixed fuel generated by vaporizing the fuel flowing out from the outflow part, and a preloading part in one of portions of a circulation path formed between the primary pump and the tank by the first pipeline and the third pipeline and preloading the fuel.

A fuel supply device of an engine includes a primary pump suctioning fuel to discharge the fuel to a first pipeline, a secondary pump connected in series to the primary pump via the first pipeline, and suctioning the fuel from the primary pump to supply the fuel through a second pipeline to an engine side, a tank storing the fuel and accommodating the secondary pump, an outflow part causing part of the fuel flowing from the first pipeline through the secondary pump to the second pipeline in the tank to flow outward, a third pipeline returning, to a suction side of the primary pump, gas-liquid mixed fuel generated by vaporizing the fuel flowing out from the outflow part, and a preloading part in one of portions of a circulation path formed between the primary pump and the tank by the first pipeline and the third pipeline and preloading the fuel.

A pump body of a high pressure fuel pump defines a compression chamber in fluid communication with a first recess dug in a first outer face. A second recess is dug in a second outer face of the body. An inlet channel opens in a conduit extending between the first recess and the second recess.

The invention relates to a fuel pump assembly for a motor vehicle, which can be upstream of a fuel pump of the motor vehicle in a fuel line of the motor vehicle, having a pump housing and a pump device arranged thereupon, by means of which fuel can be pumped into and/or through the pump housing when the pump device is in the active state thereof, wherein the pump device has at least one stroke piston pump having an inlet valve and an outlet valve which are opened and closed in alternation by pressure activation when the pump device is active. In order to provide a fuel pump assembly which enables a very energy efficient operation of a motor vehicle thereby equipped, according to the invention the inlet valve and the outlet valve are held in the open positions thereof when the pump device is inactive.

A fuel system for managing the flow of fuel to an engine having a metering valve, a bypass valve, and a shutoff valve. The system is configured to allow a primary flow of fuel in a first state to flow through the shutoff valve to the metering valve and out to an output line. In a second state the fuel system is configured to shut off the primary flow at the shutoff valve and metering valve to prevent the primary flow from traveling to the output line. The bypass valve is configured to receive the primary flow and is closed in the first state. In the second state, the metering valve closes, opening a window for a secondary flow path to a return line. When fuel flows through the secondary flow path the bypass valve opens. Wherein when the bypass valve is open the primary flow flows through the bypass valve to a return line. In addition, the bypass valve provides a secondary flow path to the shutoff valve which closes the shutoff valve.