High pressure fuel pump control apparatus for internal combustion engine
View Patent ↗There is provided a high pressure fuel pump control system for an internal combustion engine which enables fuel pressure control with high precision without being restricted by the number of cylinders of the internal combustion engine or the number of phase sensor signals and the number of cam noses which vertically drives a plunger of a high pressure fuel pump even when a camshaft phase varies by a variable valve timing mechanism by using the high pressure fuel pump with a solenoid valve. The control system has a means which changes an effective stroke by driving the solenoid valve in the high pressure fuel pump, and has a means which changes the drive timing of the high pressure fuel pump based on a cylinder recognition value of the internal combustion engine with the cam angle detecting means as an origin.
1. A high pressure fuel pump control system for an internal combustion engine, comprising:
a camshaft which is driven in synchronization with a crankshaft of the internal combustion engine;
a cam angle detecting means which generates a cam angle signal in synchronization with rotation of the camshaft;
a crank angle detecting means which generates a crank angle signal in synchronization with rotation of the crankshaft;
a means which carries out cylinder recognition of the internal combustion engine by the cam angle detecting means and the crank angle detecting means;
a high pressure fuel pump having a suction stroke and a spill stroke of the high pressure fuel pump in synchronization with the rotation of the camshaft; and
a means which changes an effective stroke by driving a solenoid valve in the high pressure fuel pump in connection with the spill stroke of the high pressure fuel pump, wherein
the means which drives the solenoid valve in the high pressure fuel pump operates in synchronization with the cam angle detecting means and the crank angle detecting means, and determines timing of the driving, with a cylinder recognition value and the cam angle detecting means as a reference position, and wherein
the means which determines timing of the driving from the cam angle detecting means based on the cylinder recognition value performs time control based on the number of the crank angle signals and a period of the crank angle signal by the crank angle detecting means from the cam angle detecting means.
2. The high pressure fuel pump control system for an internal combustion engine according to claim 1 , wherein the means which determines timing of the driving from the cam angle detecting means changes the drive timing based on the cylinder recognition value.
3. The high pressure fuel pump control system for an internal combustion engine according to claim 1 , wherein the means which determines timing of the driving from the cam angle detecting means performs a change based on time from the crank angle signal at which time at least the cam angle signal is detected.