Fuel pump control apparatus of engine
AssigneeMitsubishi Electric Corporation
InventorsYohei Yamaguchi, Yasuhiko Ishida
Life of this patent
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Abstract
By driving a fuel pump suitably to an amount of fuel according to an amount of fuel consumed by an engine and by monitoring an actual motor speed of the fuel pump, F/B control is carried out according to a target motor speed and the actual motor speed of the fuel pump. Meanwhile, by learning and storing a duty value comparable to a deviation between the target and actual motor speeds, duty driving of the fuel pump is corrected to suit an engine condition. It thus becomes possible to provide a fuel pump control apparatus of an engine capable of promoting power saving by suppressing a wasteful energy loss including a current consumption and making an internal circuit of an ECU simpler by enhancing fuel supply accuracy.
Claims2
A fuel pump control apparatus of an engine, comprising:
- an operation condition detection portion that detects an operation condition of the engine;
- a motorized fuel pump furnished with a fuel pressure regulation function;
- an injector that supplies the engine with fuel according to a fuel pressure supplied from the motorized fuel pump;
- a power generation portion that generates power by manual rotational driving of a crank shaft of the engine;
- and
- a control portion that is activated by a voltage generated by the power generation portion and computes an amount of fuel to be injected and calculates a fuel pump driving duty according to a detected value from the operation condition detection portion,
- wherein the control portion includes:
- an injector injection amount calculation functioning portion that calculates an amount of injector injection to be supplied to the engine according to the operation condition of the engine;
- a fuel consumption amount calculation functioning portion that calculates an amount of fuel the engine is consuming on a basis of the amount of injector injection, a number of cylinders of the engine, and an engine rotation speed of the engine;
- a pump driving fuel amount calculation functioning portion that calculates an amount of fuel to drive the motorized fuel pump on a basis of an output of the fuel consumption amount calculation functioning portion;
- a target motor speed calculation functioning portion that calculates a target motor speed on a basis of an output of the pump driving fuel amount calculation functioning portion;
- a driving duty calculation functioning portion that calculates the fuel pump driving duty indicating time periods during which the motorized fuel pump is driven, on a basis of an output of the target motor speed calculation functioning portion;
- and
- a feedback (F/B) correction value calculation functioning portion that finds a deviation between an actual motor speed detected from the motorized fuel pump and the target motor speed and calculates a F/B correction value of the fuel pump driving duty so that the deviation is eliminated, wherein:
- in a case where a state in which the operation condition of the engine is stable for a predetermined time period or longer and the F/B correction value is stable without yielding the deviation between the actual motor speed and the target motor speed for the predetermined time period or longer, the control portion learns the F/B correction value and stores the F/B correction value in a memory region in the control portion, so that when the control portion is activated a next time after the predetermined time period elapses, the control portion starts control by correcting the fuel pump driving duty with the stored, learned F/B correction value in addition to a subsequent F/B correction value calculated when the control portion is activated the next time.
Dependencies are inferred from the claim text.