Patent ID: 8459234

Claim:
A fuel injection device configured to be supplied with fuel from a pressure-accumulation vessel, the fuel injection device comprising: a fuel injection valve for injecting fuel, which is distributed from the pressure-accumulation vessel; a pressure sensor located in a fuel passage, which extends from the pressure-accumulation vessel to a nozzle hole of the fuel injection valve, the pressure sensor being located closer to the nozzle hole than the pressure-accumulation vessel and configured to detect pressure of fuel; a storage unit for storing individual difference information, which indicates a pre-actual use injection characteristic of the fuel injection valve, the pre-actual use injection characteristic being obtained by an examination of the fuel injection device in advance of actual use of the fuel injection device during engine operation; and a control unit configured to reflect the individual difference information on an injection control map and perform an injection control in accordance with the injection control map, wherein the individual difference information represents a relationship between the following parameters to indicate the pre-actual use injection characteristic obtained by the examination of the fuel injection device in advance of the actual use of the fuel injection device during engine operation: i) a delay time period from an actual injection time point of start of actual fuel injection of the fuel injection valve to a transition time point at which a transition point appears in a waveform of the detected pressure, the transition point being attributed to fuel injection; and ii) a change in detected pressure in a period from a time point of an output of an injection instruction to the fuel injection valve to the transition time point at which the transition point appears, in the examination of the fuel injection device in advance of the actual use, a predetermined injection instruction pulse is applied to the fuel injection valve to measure: an injection rate of fuel by using an examination equipment; the actual injection time point, which is caused by the instruction pulse, by using the pressure sensor; the change in the fuel pressure, which is attributed to the fuel injection caused by the instruction pulse, by using the pressure sensor; the delay time period being a difference between: the actual injection time point and the transition time point; wherein the injection rate is calculated based on a detection result outputted from a pressure detector provided to an inner periphery of an examination vessel of the examination equipment for detecting the change in pressure in the vessel caused by test injection from the fuel injection device in the examination.