A fluid delivery device, comprising an integrated cabinet, a pump installed in the integrated cabinet, an inlet pipeline connected to the pump, and an outlet pipeline connected to the pump; the pump comprises a motor located at the bottom portion of the integrated cabinet, a pump head located at the top portion of the integrated cabinet, and a magnetic coupling portion located between the motor and the pump head; the pump head, the magnetic coupling portion and the motor are arranged in a sequence from top to bottom; and the pump head is provided with a U-shaped flow channel and a gear mechanism therein located at the bottommost portion of the flow channel. The fluid delivery device eliminates bubbles in the solution accumulated in the pump, thus ensuring a working efficiency of fluid delivery of the pump, and ensuring precise control of a delivery amount.

A fluid gear pump gear arranged to rotate about a first axis. The fluid gear pump gear includes a concentrically disposed first hub portion and a plurality of first teeth radially projecting and circumferentially spaced about the first hub portion, the first hub portion and the first teeth being coated with a vapor-deposited of cavitation resistant coating. The gear also includes a first shaft on which the first hub portion is carried.

An outer wall surface of an output end portion includes a pair of first plane surfaces which are formed at different positions in its circumferential direction. An inner wall surface of a fitting hole includes a pair of second plane surfaces which are formed at different positions in the circumferential direction. A clearance between one of the pair of first plane surfaces and one of the pair of second plane surfaces is made larger from one side toward the other side in an axial direction in a state that a rotary shaft and an impeller are concentric with each other.

An evaporation leakage checking system includes a pump, a pump passage unit, a tank passage unit, a specified passage unit, an atmosphere passage unit, a flow-passage area changing unit, an atmosphere valve unit, a pressure sensing unit, and a control unit. The control unit includes a calculating unit that calculates a leakage threshold, based on a first pressure, a first area, an Nth pressure, an Nth area, and a reference area that is predetermined, and a leakage checking unit that activates the pump, closes the atmosphere passage unit by changing the flow-passage area of the atmosphere passage unit by using the atmosphere valve unit, and checks the existence of the evaporation leakage based on the leakage threshold and a checking pressure that is the pressure sensed by the pressure sensor in a case where a communication between the tank passage unit and the pump passage unit is allowed.

A fuel pump unit includes a suction filter and a fuel pump. The fuel pump includes: a rotatable shaft placed along a rotational axis; a rotor portion that rotates in response to rotation of the rotatable shaft; a suction hole portion, through which the fuel is suctioned into an inside of a rotor receiving chamber; and an outer peripheral wall that surrounds the suction hole portion. The suction filter includes: a filter element that filters the fuel and conducts the filtered fuel into an inside space; and a columnar hole portion having an inner peripheral wall, while the outer peripheral wall and the inner peripheral wall are fitted with each other, so that the columnar hole portion communicates between the inside space and the suction hole portion. The columnar hole portion is placed such that the rotational axis extends on an inner side of the inner peripheral wall.

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.

An outer wall surface of an output end portion includes a pair of first plane surfaces which are formed at different positions in its circumferential direction. An inner wall surface of a fitting hole includes a pair of second plane surfaces which are formed at different positions in the circumferential direction. A clearance between one of the pair of first plane surfaces and one of the pair of second plane surfaces is made larger from one side toward the other side in an axial direction in a state that a rotary shaft and an impeller are concentric with each other.

A dual compressor turbocharger includes two compressors. One compressor supplies fuel pressure, and one compressor supplies air pressure. The dual compressor turbocharger includes a turbine driven by exhaust of an engine and a shaft coupled to the turbine. The first compressor is mounted on the shaft and includes a first inlet coupled to an air supply and a first outlet coupled to an air intake of the engine. The second compressor is mounted on the shaft and includes a second inlet coupled to a fuel supply and a second outlet coupled to a fuel supply rail of the engine.

A dual compressor turbocharger includes two compressors. One compressor supplies fuel pressure, and one compressor supplies air pressure. The dual compressor turbocharger includes a turbine driven by exhaust of an engine and a shaft coupled to the turbine. The first compressor is mounted on the shaft and includes a first inlet coupled to an air supply and a first outlet coupled to an air intake of the engine. The second compressor is mounted on the shaft and includes a second inlet coupled to a fuel supply and a second outlet coupled to a fuel supply rail of the engine.