Fuel supply device

Abstract

A fuel supply device is disclosed. Through a simple structure, the fuel supply device is capable of realizing reduction of fuel suction pressure loss, restraint of steam suction, prevention of the phenomena that steam stays inside a pump, stable pump output, stability control over fuel pressure, and the like. In the fuel supply device, a pump part (20) is driven through an electric motor part (10), fuel pumped in the pump part (20) is pressurized and discharged. The pump part (20) comprises a housing (21) equipped with a suction connection head (23) and a discharge connection head (24), an oil cylinder (26) which is accommodated inside the housing and equipped with multiple pistons (25), a shaft (11) arranged at the electric motor part (10), an inclined plate (12) which enables reciprocating motion of the multiple pistons, multiple suction ports (26b) which serve as fuel passageways for guiding the fuel into a plenum chamber and a bush (28) which is roughly cylindrical-shaped, wherein the multiple suction ports (26b) run through the cylinder in an axial direction in such a way that the suction ports correspond to all pistons, two end parts of the bush are inserted and kept in the oil cylinder and the electric motor part, fuel pumped in through the suction connection head is guided to multiple suction ports, and the pistons (25) and the suction ports (26b) are disposed in different spaces (28c) which are separated from each other.

Description

technical field [0001] The present invention relates to a fuel supply device for supplying fuel to, for example, a fuel injection device of an internal combustion engine. Background technique [0002] The piston type fuel pump disclosed in Patent Documents 1 and 2 includes: a swash plate driven by an electric motor; and a cylinder having a plurality of pistons reciprocating with the rotation of the swash plate, and a cylinder for introducing fuel into the cylinder is provided on the inlet side of the cylinder. Suction port of the pressurized chamber. [0003] prior art literature [0004] patent documents [0005] Patent Document 1: Japanese Patent Laid-Open No. 2009-108683 [0006] Patent Document 2: Japanese Patent Laid-Open No. 2011-26962 [0007] In this kind of fuel supply device, due to the rotation of the motor rotor and the rotation of the swash plate, a swirling flow is likely to be generated in the fuel in the pump, and the fuel sucked into the suction port of ...

AI Technical Summary

Problems solved by technology

[0008] Alternatively, the fuel is disturbed by the reciprocating action of the piston or a return spring that exerts a return force on the piston

Both of these situations increase the pressure loss, which tends to generate vapors (bubbles) in the fuel

[0009] In addition, since the swirl flow formed substantially parallel to the cylinder end face is in the direction perpendicular to the suction port, the fuel drawn into the suction port is sucked into the suction port after turning sharply at right angles from the flow direction of the swirl flow, resulting in pressure increased losses

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