Fuel injection system and controller for fuel injection system
AssigneeDenso Corporation
InventorTamaki Ishikawa
Life of this patent
Estimating the term…
Abstract
A fuel pump includes a camshaft that rotates in accordance with operation of an engine and a tappet provided in contact the camshaft. An ECU includes an angle determination unit configured to determine whether a rotation angle from a start of rotation of the camshaft when starting the engine is under a predetermined angle required for forming an oil film on a sliding portion of the tappet, and a control unit configured to, when the rotation angle from the start of rotation of the camshaft is determined to be under the predetermined angle, execute a limit process including at least one of limiting a fuel discharge pressure of the fuel pump or limiting a rotation of the camshaft.
Claims8
A controller for a fuel injection system including a fuel pump having a camshaft that rotates in accordance with operation of an internal combustion engine, a tappet provided in contact with a cam of the camshaft that converts the rotation of the camshaft into linear motion, and a plunger that reciprocates according to the linear motion of the tappet, the fuel pump being configured to suck and discharge fuel according to the reciprocation of the plunger, an accumulator that stores high pressure fuel discharged from the fuel pump, and a fuel injection valve that injects the high pressure fuel stored in the accumulator into a combustion chamber of the internal combustion engine, the controller comprising:
- an angle determination unit configured to determine whether a rotation angle from a start of rotation of the camshaft when starting the internal combustion engine is under a predetermined angle required for forming an oil film on a sliding portion of the tappet, and
- a control unit configured to:
- when the rotation angle from the start of rotation of the camshaft is determined to be under the predetermined angle, execute a limit process including at least one of limiting a fuel discharge pressure of the fuel pump or limiting a rotation of the camshaft, and
- when the rotation angle is determined to have exceeded the predetermined angle after having executed the limit process, cancel the limit process execution.
A fuel injection system for an internal combustion engine, comprising:
- a fuel pump including:
- a camshaft that rotates in accordance with operation of the internal combustion engine,
- a tappet provided in contact with a cam of the camshaft that converts the rotation of the camshaft into linear motion, and
- a plunger that reciprocates according to the linear motion of the tappet, the fuel pump being configured to suck and discharge fuel according to the reciprocation of the plunger;
- an accumulator that stores the fuel discharged from the fuel pump;
- a fuel injection valve that injects the fuel stored in the accumulator into a combustion chamber of the internal combustion engine;
- and
- an electronic control unit including a processor and a memory, the memory having stored thereon instructions which when executed by the processor causes the processor to:
- determine whether a rotation angle from a start of rotation of the camshaft when starting the internal combustion engine is under a predetermined angle required for forming an oil film on a sliding portion of the tappet,
- upon determining that the rotation angle from the start of rotation of the camshaft is under the predetermined angle, execute a limit process including at least one of limiting a fuel discharge pressure of the fuel pump or limiting a rotation of the camshaft, and
- upon determining that the rotation angle is greater than the predetermined angle after having executed the limit process, cancel the limit process execution.
Dependencies are inferred from the claim text.