Patent ID: 7380539
Filing Date: 2008-06-03
Classification: F02D,F02M,Y02T

Abstract:
1. A fuel supply apparatus for an internal combustion engine having first fuel injection means for injecting fuel into a cylinder, and second fuel injection means for injecting fuel into an intake manifold, comprising: pressure monitoring means for monitoring a pressure of the fuel in said first fuel injection means; relief means for externally relieving fuel within a delivery pipe to which said first fuel injection means is attached, said relief means including a high-pressure fuel pump for pressurizing the fuel and supplying the high-pressure fuel to said delivery pipe, a relief path for relieving the fuel from said delivery pipe to a fuel tank, and a relief valve provided at said relief path; and control means for actuating said relief means when the fuel pressure obtained by said pressure monitoring means is equal to or greater than a reference pressure to relieve the fuel within said delivery pipe so as to decrease the fuel pressure while actuating the high-pressure fuel pump for a period of time in order to supply the high-pressure fuel to said delivery pipe and circulate the fuel through the relief path to cool the first injection means, and for stopping said relief means when the fuel pressure becomes a critical pressure for fuel injection in minimum injection quantity of said first fuel injection means.