A fuel consumption-measuring system includes a feed line, a first pump which pumps fuel from a tank via the feed line to a consumer, a fuel consumption-measuring device in the feed line, a first return line which branches off at the consumer and opens into the feed line between the fuel consumption-measuring device and the consumer, a second return line which branches off from the feed line between the first pump and the fuel consumption-measuring device which opens into the tank, a branch which leads from the feed line into the second return line, a heat exchanger, and a flow device arranged in the first and second return lines. The flow device provides an equal volume flow at an opening of the first return line into the feed line and at the branch leading from the feed line into the second return line.

A discharge valve of a high-pressure pump is placed in a discharge passage and is openable to enable flow of fuel from a pressurizing chamber to a discharge outlet in response to a fuel pressure difference between the pressurizing chamber side and the discharge outlet side. A relief is placed in a relief passage. The relief passage communicates between a branching portion, which is located on a side of the discharge valve where the discharge outlet is placed in the discharge passage, and a return portion, which merges with a damper chamber. The relief valve is openable to enable flow of the fuel from the branching portion to the return portion in response to a fuel pressure difference between the branching portion side and the return portion side. A discharge passage orifice is placed between the discharge valve and the branching portion in the discharge passage and constricts a flow passage cross-sectional area of the discharge passage.

The present invention relates to a fuel pump (1) which comprises a pump housing (2), a delivery element (3) for delivering fuel, a heat-generating actuator (4) for actuating the delivery element (3), a first fuel path (5) which leads from an inlet (20) to a delivery space (7), and a second fuel path (6) which leads from the inlet (20) past the heat-generating actuator (4) to a first housing opening (21), wherein the first housing opening (21) is arranged above the inlet (20) in the vertical direction (V). The present invention also relates to a fuel pump arrangement which comprises a fuel pump (1) according to the invention and a fuel tank (10) in which the fuel pump (1) is at least partially and preferably entirely arranged. The present invention also relates to a method for operating a fuel pump (1).

A fuel supply system includes a feeder fuel circuit configured to: (i) convey a first fuel in a direction of a mixing tank via a first pump device proceeding from a first fuel tank for a first fuel type; or (ii) convey a second fuel in the direction of the mixing tank via the first pump device proceeding from a second fuel tank for a second fuel type; and a booster fuel circuit configured to convey fuel via a second pump device proceeding from the mixing tank in a direction of at least one marine diesel engine, the booster fuel circuit having an automatic fine filter positioned upstream of or downstream of the at least one marine diesel engine and in the booster fuel circuit, respectively.

A fuel return device to be mounted to a fuel tank for returning an excess fuel flowing out from an engine through a fuel return piping member to the fuel tank includes a fuel return pipe connected to the fuel return piping member. The fuel return pipe has an opening that is opened to an upper space formed in the fuel tank with the fuel return pipe mounted to the fuel tank.

A fuel supply device includes a fuel pump, a sub-tank configured to store a fuel, a leakage passage configured to return a part of a pressurized fuel discharged from the fuel pump into the sub-tank, and a fuel filter disposed at a bottom part of the sub-tank. The fuel filter includes a filter member that is configured to filter the fuel to be suctioned into the fuel pump. A downstream end of the leakage passage includes a linear passage part linearly extending from a position above the filter member toward the filter member. The fuel supply device also includes a direction change wall part configured to change the flow direction of the pressurized fuel jetted from the linear passage part so as to prevent the pressurized fuel from directly impacting the filter member.

A fuel supply device includes a fuel pump, a sub-tank configured to store a fuel, a leakage passage configured to return a part of a pressurized fuel discharged from the fuel pump into the sub-tank, and a fuel filter disposed at a bottom part of the sub-tank . The fuel filter includes a filter member that is configured to filter the fuel to be suctioned into the fuel pump. A downstream end of the leakage passage includes a linear passage part linearly extending from a position above the filter member toward the filter member. The fuel supply device also includes a direction change wall part configured to change the flow direction of the pressurized fuel jetted from the linear passage part so as to prevent the pressurized fuel from directly impacting the filter member.

In a pressure regulator, a valve element nozzle is supported by a diaphragm, which partitions between an inlet portion and an outlet portion. The outlet portion includes an inner cover and an outer cover. The inner cover receives an adjusting spring in an inside space of the inner cover. A primary communication hole is formed in the inner cover to oppose the valve element nozzle, and a secondary communication hole is formed in the inner cover at a location, which is on a radially outer side of the primary communication hole. The outer cover covers the inner cover and thereby forms a fuel space, which is communicated with the inside space through the primary and secondary communication holes, at a location between the inner cover and the outer cover.

A fuel pump for a liquid fuel water injection system of a motor vehicle is provided. The fuel pump includes a low-pressure pump that mixes water from a water tank of the motor vehicle with liquid fuel from a fuel tank of the motor vehicle to a liquid fuel water emulsion and provides the liquid fuel water emulsion at a low pressure. A high-pressure pump is in fluid communication with the low-pressure pump and compresses the liquid fuel water emulsion from the low pressure to a high pressure for injecting the liquid fuel water emulsion into an internal combustion engine of the motor vehicle via an injection rail of the motor vehicle. A pump drive drives the low-pressure pump and the high-pressure pump synchronously with a pump frequency independently from an engine speed of the internal combustion engine of the motor vehicle.

Fuel isolation systems, apparatuses and methods are described. In some embodiments, a system comprises a fuel tank, a fuel pump, an engine, a firewall, a fuel line from the fuel tank to the engine, a connector coupled inline with the fuel line on a cold side of the fuel line, a valve coupled to the connector, an air feed line coupled to an air source and to the valve. In the event of an engine fire condition, a control unit outputs signaling to turn off the fuel pump and operate the valve to introduce air from the air source into the fuel line. The introduced air provides a siphon break in the fuel line such that the only fuel that can pass the firewall is the remaining fuel in the fuel line downstream of the connector and the introduced air.