Imbalance detection device, imbalance detection system, data analysis device, and controller for internal combustion engine

Patent metadata

Field	Value
Publication number	US-2020271069-A1
Application number	US-202016785720-A
Country	US
Kind code	A1
Filing date	Feb 10, 2020
Priority date	Feb 21, 2019
Publication date	Aug 27, 2020
Grant date	—

Abstract

An imbalance detection device is provided. An obtainment process includes obtaining a rotation waveform variable based on a detection value of a sensor that detects a rotational behavior of a crankshaft, and an air-fuel ratio detection variable in each of a plurality of first intervals. A calculation process includes calculating an imbalance variable based on an output of a mapping having a value obtained by the obtainment process as an input. The imbalance variable indicates a degree of variations in an air-fuel ratio of the internal combustion engine. The rotation waveform variable indicates a difference between instantaneous speed variables that are variables corresponding to the rotational speed of the crankshaft in each of the second intervals.

First claim

What is claimed is:

1 . An imbalance detection device applied to a multi-cylinder internal combustion engine, the imbalance detection device comprising:
a storage device; and an execution device, wherein the storage device is configured to store mapping data that is data defining a mapping, the mapping having a rotation waveform variable and an air-fuel ratio detection variable as an input, the air-fuel ratio detection variable being a variable corresponding to an output of an air-fuel ratio sensor in each of a plurality of first intervals, and the mapping outputting an imbalance variable that is a variable indicating a degree of variations in an air-fuel ratio of the internal combustion engine, the execution device is configured to execute
an obtainment process of obtaining the rotation waveform variable based on a detection value of a sensor that detects a rotational behavior of a crankshaft, and the air-fuel ratio detection variable in each of a plurality of first intervals,
a calculation process of calculating the imbalance variable based on an output of the mapping having a value obtained by the obtainment process as the input, and
a response process of operating predetermined hardware based on a calculation result of the calculation process to respond to a large degree of variations in the air-fuel ratio,
the rotation waveform variable is a variable indicating a difference between instantaneous speed variables that are variables corresponding to a rotational speed of the crankshaft in each of a plurality of second intervals, the first interval and the second interval are both angular intervals of the crankshaft smaller than an appearance interval of a compression top dead center, and the rotation waveform variables and the air-fuel ratio detection variables, which are inputs to the mapping, are respectively time series data within a predetermined angular interval larger than the appearance interval.

2 . The imbalance detection device according to claim 1 , wherein
the input to the mapping includes a half order component of a rotation frequency of the crankshaft based on the detection value of the sensor that detects the rotational behavior of the crankshaft, the obtainment process includes a process of obtaining a half order component variable that is a variable defining the half order component, and the calculation process is a process of calculating the imbalance variable based on the output of the mapping in which the half order component variable obtained by the obtainment process is further included in the input to the mapping.

3 . The imbalance detection device according to claim 1 , wherein
the input to the mapping includes an operating point variable that is a variable defining an operating point of the internal combustion engine, the obtainment process includes a process of obtaining the operating point variable, and the calculation process is a process of calculating the imbalance variable based on the output of the mapping in which the operating point variable obtained by the obtainment process is further included in the input to the mapping.

4 . The imbalance detection device according to claim 1 , wherein
the input to the mapping includes moderator variables that are variables for adjusting a combustion speed of air-fuel mixture in a combustion chamber of the internal combustion engine by an operation of an operation portion of the internal combustion engine, the obtainment process includes a process of obtaining the moderator variable, and the calculation process is a process of calculating the imbalance variable based on the output of the mapping in which the moderator variable obtained by the obtainment process is further included in the input to the mapping.

5 . The imbalance detection device according to claim 1 , wherein
the input to the mapping includes a driveline system state variable that is a variable indicating a state of a driveline system connected to the crankshaft, the obtainment process includes a process of obtaining the driveline system state variable, and the calculation process is a process of calculating the imbalance variable based on the output of the mapping in which the driveline system state variable obtained by the obtainment process is further included in the input to the mapping.

6 . The imbalance detection device according to claim 1 , wherein
the input to the mapping includes a road surface state variable that is a variable indicating a state of a road surface on which a vehicle to which the internal combustion engine is mounted travels, the obtainment process includes a process of obtaining the road surface state variable, and the calculation process is a process of calculating the imbalance variable based on the output of the mapping in which the road surface state variable obtained by the obtainment process is further included in the input to the mapping.

7 . The imbalance detection device according to claim 1 , wherein
the rotation waveform variable is configured as a variable indicating a difference between the instantaneous speed variables by the instantaneous speed variable in each of the second intervals, the obtainment process includes a process of obtaining the instantaneous speed variable in each of the second intervals as the rotation waveform variable, and the calculation process is a process of calculating the imbalance variable by having the instantaneous speed variable in each of the second intervals as the input to the mapping as the rotation waveform variable.

8 . The imbalance detection device according to claim 1 , wherein
the storage device includes a plurality of types of the mapping data, and the calculation process includes a selection process of selecting the mapping data to be used for calculating the imbalance variable from the plurality of types of mapping data.

9 . The imbalance detection device according to claim 1 , wherein
the internal combustion engine includes
a canister that collects fuel vapor in a fuel tank that stores fuel to be injected from a fuel injection valve,
a purge passage that connects the canister and an intake passage of the internal combustion engine to each other, and
an adjustment device for adjusting a flow rate of the fuel vapor flowing from the canister into the intake passage through the purge passage,
the calculation process includes both of
a process of calculating the imbalance variable by having data obtained by the obtainment process when the flow rate of the fuel vapor is zero as the input to the mapping, and
a process of calculating the imbalance variable by having data obtained by the obtainment process when the flow rate of the fuel vapor is greater than zero as the input to the mapping, and
the response process is a process of, when the flow rate of the fuel vapor is greater than zero, operating the predetermined hardware based on the imbalance variable calculated by having the data obtained by the obtainment process when the flow rate of the fuel vapor is greater than zero as the input to the mapping.

10 . The imbalance detection device according to claim 1 , wherein
the internal combustion engine includes
a canister that collects fuel vapor in a fuel tank that stores fuel to be injected from a fuel injection valve,
a purge passage that connects the canister and an intake passage of the internal combustion engine to each other, and
an adjustment device for adjusting a flow rate of the fuel vapor flowing from the canister into the intake passage through the purge passage,
the calculation process includes both of
a process of calculating the imbalance variable by having data obtained by the obtainment process when the

Assignees

• Toyota Motor Co Ltd

Inventors

• Muto Harufumi
• Katayama Akihiro
• Mori Kohei
• Hashimoto Yosuke

Classifications

• F02D41/2454 Primary

  Learning of the air-fuel ratio control · CPC title

• F02D41/2477

  characterised by the method used for learning · CPC title

• F02D41/2445

  characterised by a plurality of learning conditions or ranges · CPC title

• F02D41/0085 Primary

  Balancing of cylinder outputs, e.g. speed, torque or air-fuel ratio · CPC title

• F02M25/0836

  Arrangement of valves controlling the admission of fuel vapour to an engine, e.g. valve being disposed between fuel tank or absorption canister and intake manifold · CPC title