Patent ID: 6877489
Filing Date: 2005-04-12
Classification: F02M

Abstract:
1. A fuel injection device adapted to inject fuel from a fuel tank into a fuel intake part of an internal combustion engine, said fuel injection device comprising: a body; an intake section provided at a lower section of said body and arranged for intake of the fuel from the fuel tank; a return section provided at an upper section of said body and arranged to return surplus fuel to the fuel tank; an injection nozzle mounted to said body and arranged to inject the fuel into the fuel intake part of the internal combustion engine; and a plunger pump mounted in said body and comprising a plunger-receiving body having a passage extending therethrough, a plunger disposed in said passage of said plunger-receiving body, and a pressure chamber at least partly formed in said passage of said plunger-receiving body at an end of said plunger and communicated with said intake section, said plunger being movably disposed in said passage for reciprocal movement therein in a first direction to perform an intake stroke to draw the fuel into said pressure chamber and in a second direction to perform a pressurizing stroke to pressurize the fuel in said pressure chamber; wherein said plunger pump further includes a plunger-driving motor operably coupled to said plunger to drive said plunger in at least one of said first and second directions; wherein a circulation passage is provided between said plunger-receiving body and said plunger-driving motor and communicates between said intake section and said return section to guide at least a portion of the fuel from said intake section toward said return section; and wherein said return section is located at a position higher than said intake section such that fuel vapor present in the fuel at said intake section floats upward through said circulation passage to carry the fuel to said return section.