Abnormality diagnosis device for in-cylinder pressure sensor

Patent metadata

Field	Value
Publication number	US-2020200112-A1
Application number	US-201916663750-A
Country	US
Kind code	A1
Filing date	Oct 25, 2019
Priority date	Dec 21, 2018
Publication date	Jun 25, 2020
Grant date	—

Abstract

An abnormality diagnosis device of an in-cylinder pressure sensor is provided. The device carries out a performance determination in which a performance quality of the sensor is determined based on an electric signal inputted from the sensor. The device carries out a first determination in which the performance determination is performed at a given timing, a performance recovery in which a given deposit removal control is executed in which a deposit accumulating inside the combustion chamber is removed when the performance quality of the in-cylinder pressure sensor is determined to fall below a given reference value, and a second determination in which the performance determination is carried out again after the performance recovery. In the second determination, the in-cylinder pressure sensor is diagnosed as abnormal when the performance quality of the sensor is determined to fall below the given reference value.

First claim

What is claimed is:

1 . An abnormality diagnosis device of an in-cylinder pressure sensor attached to an engine of an automobile to detect pressure inside a combustion chamber, comprising:
a processor configured to execute a sensor diagnosing module to carry out a performance determination in which a performance quality of the in-cylinder pressure sensor is determined based on an electric signal inputted from the in-cylinder pressure sensor, the sensor diagnosing module carrying out: a first determination in which the performance determination is performed at a given timing; a performance recovery in which a given deposit removal control is executed in which a deposit accumulating inside the combustion chamber is removed when the performance quality of the in-cylinder pressure sensor is determined to fall below a given reference value; and a second determination in which the performance determination is carried out again after the performance recovery, wherein in the second determination, the in-cylinder pressure sensor is diagnosed as abnormal when the performance quality of the in-cylinder pressure sensor is determined to fall below the given reference value.

2 . The device of claim 1 ,
wherein the engine includes a spark plug configured to ignite a mixture gas inside the combustion chamber, and wherein the given deposit removal control includes advancing the ignition timing of the spark plug.

3 . The device of claim 1 , wherein the engine includes:
a spark plug configured to ignite a mixture gas inside the combustion chamber; an intake passage through which intake air is introduced into the combustion chamber; an exhaust passage through which exhaust gas generated in the combustion chamber is discharged; an exhaust gas recirculation (EGR) passage communicating the intake passage with the exhaust passage and configured to recirculate a portion of the exhaust gas to the intake passage; and an EGR valve configured to adjust an amount of the exhaust gas flowing inside the EGR passage, wherein the deposit removal control includes igniting the mixture gas by the spark plug to cause combustion in a state where the EGR valve is controlled to reduce the amount of the exhaust gas introduced into the combustion chamber.

4 . The device of claim 1 , wherein the performance determination is carried out by estimating a pressure inside the combustion chamber at a given timing by way of a calculation, and comparing the estimated pressure with an output value of the in-cylinder pressure sensor at the given timing.

5 . The device of claim 4 , wherein the estimated pressure is corrected according to an engine speed.

6 . The device of claim 1 , wherein the performance determination is carried out when a supply of fuel to the engine is stopped.

7 . The device of claim 1 , wherein when the in-cylinder pressure sensor is diagnosed as abnormal, a notification of the diagnosis result is carried out.

8 . A method of diagnosing abnormality of an in-cylinder pressure sensor attached to an engine of an automobile to detect pressure inside a combustion chamber, comprising carrying out:
a performance determination in which a performance quality of the in-cylinder pressure sensor is determined based on an electric signal inputted from the in-cylinder pressure sensor; a first determination in which the performance determination is performed at a given timing; a performance recovery in which a given deposit removal control is executed in which a deposit accumulating inside the combustion chamber is removed when the performance quality of the in-cylinder pressure sensor is determined to fall below a given reference value; and a second determination in which the performance determination is carried out again after the performance recovery, wherein in the second determination, the in-cylinder pressure sensor is diagnosed as abnormal when the performance quality of the in-cylinder pressure sensor is determined to fall below the given reference value.

Assignees

• Mazda Motor

Inventors

• Fujiwara Shoji
• Hashimoto Hidetoshi
• Okumura Takuji
• Nakagawa Shigeru
• Torii Yasushi
• Kinoshita Masayuki
• Tsumura Yuichiro
• Tanaka Daisuke
• Maiguma Taiki

Classifications

• F02D41/3041

  with means for triggering compression ignition, e.g. spark plug · CPC title

• Y02T10/40

  Engine management systems · CPC title

• F02D41/0205

  using an auxiliary engine speed control (engine speed control per se F02D31/00) · CPC title

• F02P5/153

  dependent on combustion pressure · CPC title

• F02D41/1479

  Using a comparator with variable reference · CPC title