Control device for compression-ignited internal combustion engine

Patent metadata

Field	Value
Publication number	US-9957913-B2
Application number	US-201515112545-A
Country	US
Kind code	B2
Filing date	Jan 19, 2015
Priority date	Jan 21, 2014
Publication date	May 1, 2018
Grant date	May 1, 2018

Abstract

A control device for a compression-ignited internal combustion engine includes a nozzle that includes plural injection holes arranged at intervals in the circumferential direction and that directly injects fuel to a combustion chamber, a piston that includes a cavity with an inner circumferential side surface to which a distance from the nozzle varies in the circumferential direction, a first injection hole for injecting fuel to a portion of the inner circumferential side surface to which the distance from the nozzle is the largest out of the plural injection holes, a second injection hole for injecting fuel to a portion of the inner circumferential side surface to which the distance from the nozzle is the smallest out of the plural injection holes, a detection unit that detects a heat release rate in the combustion chamber, and a control unit that determines which of the first and second injection holes is abnormal.

First claim

The invention claimed is:

1. A control device for a compression-ignited internal combustion engine, the compression-ignited internal combustion engine including
a nozzle in which a plurality of injection holes are arranged at intervals in a circumferential direction of the nozzle, the plurality of injection holes including a first injection hole and a second injection hole, the nozzle being configured to directly inject fuel to a combustion chamber, and
a piston provided with a cavity, the cavity being configured such that i) a distance from the first injection hole to an inner circumferential surface of the cavity is larger than a distance from any other injection hole to the inner circumferential surface of the cavity and ii) a distance from the second injection hole to the inner circumferential surface of the cavity is shorter than a distance from any other injection hole to the inner circumferential surface of the cavity, the control device comprising:
an electronic control unit configured to:
a) detect a heat release rate in the combustion chamber; and
b) determine which of the first injection hole and the second injection hole is abnormal based on a magnitude of one relative to the other between a first-half determination value of the heat release rate and a second-half determination value of the heat release rate, the first-half determination value being a maximum value of the heat release rate after a fuel spray from the second injection hole in main injection is ignited and before a fuel spray from the first injection hole is ignited, the second-half determination value being a maximum value of the heat release rate after the fuel spray from the first injection hole is ignited.

2. The control device according to claim 1 , wherein the electronic control unit is configured to determine that the first injection hole is abnormal when the magnitude of the first-half determination value relative to the second-half determination value is greater than a first predetermined value, and
wherein the electronic control unit is configured to determine that the second injection hole is abnormal when the magnitude of the first-half determination value relative to the second-half determination value is less than a second predetermined value which is smaller than the first predetermined value.

3. The control device according to claim 1 , wherein the electronic control unit is configured to determine that the second injection hole is abnormal when the magnitude of the second-half determination value relative to the first-half determination value is greater than a first predetermined value, and
wherein the electronic control unit is configured to determine that the first injection hole is abnormal when the magnitude of the second-half determination value relative to the first-half determination value is less than a second predetermined value which is smaller than the first predetermined value.

4. The control device according to claim 1 , wherein the electronic control unit is configured to perform a process of suppressing generation of smoke when the electronic control unit determines that the first injection hole is abnormal.

5. The control device according to claim 1 , wherein the electronic control unit is configured to perform a process of improving ignitionability of fuel when the electronic control unit determines that the second injection hole is abnormal.

6. A control device for a compression-ignited internal combustion engine, the compression-ignited internal combustion engine including
a nozzle in which a plurality of injection holes are arranged at intervals in a circumferential direction of the nozzle, the plurality of injection holes including a first injection hole and a second injection hole, the nozzle being configured to directly inject fuel to a combustion chamber, and
a piston provided with a cavity, the cavity being configured such that i) a distance from the first injection hole to an inner circumferential surface of the cavity is larger than a distance from any other injection hole to the inner circumferential surface of the cavity and ii) a distance from the second injection hole to the inner circumferential surface of the cavity is shorter than a distance from any other injection hole to the inner circumferential surface of the cavity, the control device comprising:
an electronic control unit configured to:
a) detect a heat release rate in the combustion chamber; and
b) determine which of the first injection hole and the second injection hole is abnormal based on a magnitude of one relative to the other between a first-half determination value of the heat release rate and a second-half determination value of the heat release rate, the first-half determination value being a value of the heat release rate when a decreasing rate of the heat release rate is the largest after a fuel spray from the second injection hole in main injection is ignited and before a fuel spray from the first injection hole is ignited, the second-half determination value being a maximum value of the heat release rate after the fuel spray from the first injection hole is ignited.

7. The control device according to claim 6 , wherein the electronic control unit is configured to determine that the first injection hole is abnormal when the magnitude of the first-half determination value relative to the second-half determination value is greater than a first predetermined value, and
wherein the electronic control unit is configured to determine that the second injection hole is abnormal when the magnitude of the first-half determination value relative to the second-half determination value is less than a second predetermined value which is smaller than the first predetermined value.

8. The control device according to claim 6 , wherein the electronic control unit is configured to determine that the second injection hole is abnormal when the magnitude of the second-half determination value relative to the first-half determination value is greater than a first predetermined value, and
wherein the electronic control unit is configured to determine that the first injection hole is abnormal when the magnitude of the second-half determination value relative to the first-half determination value is less than a second predetermined value which is smaller than the first predetermined value.

9. The control device according to claim 6 , wherein the electronic control unit is configured to perform a process of suppressing generation of smoke when the electronic control unit determines that the first injection hole is abnormal.

10. The control device according to claim 6 , wherein the electronic control unit is configured to perform a process of improving ignitionability of fuel when the electronic control unit determines that the second injection hole is abnormal.

Assignees

• Toyota Motor Co Ltd

Inventors

• Ono Tomoyuki

Classifications

• Y02T10/125

  Cross-Sectional Technologies · mapped topic

• F02B23/0672 Primary

  Omega-piston bowl, i.e. the combustion space having a central projection pointing towards the cylinder head and the surrounding wall being inclined towards the cylinder center axis (the surrounding wall being exactly vertical F02B23/0696) · CPC title

• F02D35/023

  by determining the cylinder pressure · CPC title

• Y02T10/40

  Engine management systems · CPC title

• F02M2200/06

  Fuel-injection apparatus having means for preventing coking, e.g. of fuel injector discharge orifices or valve needles · CPC title