WO2024004087A1

WO2024004087A1 - Abnormality determination device

Info

Publication number: WO2024004087A1
Application number: PCT/JP2022/026001
Authority: WO
Inventors: 芽松尾; 幸久筧; 俊央松本
Original assignee: いすゞ自動車株式会社
Priority date: 2022-06-29
Filing date: 2022-06-29
Publication date: 2024-01-04

Abstract

Provided is an abnormality determination device that reliably determines disengagement of an intake pressure sensor from an intake pipe. This abnormality determination device (6) is provided with: an acquisition unit (13) that acquires an intake pressure from an intake pressure sensor (11) disposed in an intake pipe (2); and a determination unit (14) that determines, during load operation of an engine (1), disengagement of the intake pressure sensor from the intake pipe on the basis of a degree of an intake pressure acquired by the acquisition unit.

Description

Abnormality determination device

The present disclosure relates to an abnormality determination device.

Conventionally, the pressure in the intake pipe connected to the engine has been measured by an intake pressure sensor, and devices that perform on-board diagnosis (OBD), which is a function to detect malfunctions of this intake pressure sensor, have been put into practical use. . Here, it is required to reliably detect failure of the intake pressure sensor.

Therefore, as a technique for reliably detecting a failure of an intake pressure sensor, for example, Patent Document 1 discloses a sensor that identifies one of the intake pipe pressure sensor and the atmospheric pressure sensor that has an abnormality when the engine is stopped. An abnormality determination device is disclosed. This sensor abnormality determination device determines whether or not the difference between the detected value of the intake pipe pressure sensor and the estimated atmospheric pressure is within a predetermined tolerance range. Identify the sensor with.

Japanese Patent Application Publication No. 2008-303718

However, the device of Patent Document 1 detects failure of the intake pressure sensor, but does not detect detachment of the intake pressure sensor from the intake pipe. Therefore, if the intake pressure sensor becomes detached from the intake pipe due to vehicle vibration or human factors, there is a possibility that the abnormality cannot be detected.

An object of the present disclosure is to provide an abnormality determination device that reliably determines whether an intake pressure sensor has come off from an intake pipe.

An abnormality determination device according to the present disclosure includes an acquisition unit that acquires intake pressure from an intake pressure sensor disposed in an intake pipe, and a magnitude of the intake pressure acquired by the acquisition unit when the engine is operated under load. and a determining section that determines whether the intake pressure sensor has come off from the intake pipe based on the above information.

According to the present disclosure, it is possible to reliably determine whether the intake pressure sensor has come off from the intake pipe.

FIG. 1 is a diagram showing the configuration of a vehicle equipped with an abnormality determination device according to an embodiment of the present disclosure. FIG. 2 is a flowchart showing the operation of the embodiment.

Hereinafter, embodiments according to the present disclosure will be described based on the accompanying drawings.

FIG. 1 shows the configuration of a vehicle equipped with an abnormality determination device according to an embodiment of the present disclosure. The vehicle includes an engine 1 , an intake pipe 2 , an exhaust pipe 3 , an EGR (Exhaust Gas Recirculation) pipe 4 , an engine control section 5 , an abnormality determination device 6 , and a notification section 7 . Note that examples of the vehicle include a truck and a van.

The engine 1 is for driving a vehicle, and is comprised of, for example, a so-called four-stroke engine that repeats four strokes: an intake stroke, a compression stroke, an expansion stroke, and an exhaust stroke. Examples of the engine 1 include a diesel engine.

The intake pipe 2 is formed to extend from the outside to the engine 1, and supplies air taken in from the outside to the engine 1. The intake pipe 2 has an intake manifold 2a. The intake manifold 2a is connected to the engine 1 at the end of the intake pipe 2, and distributes and supplies air flowing through the intake pipe 2 to each cylinder of the engine 1.

Further, in the intake pipe 2, a compressor 8a of the turbocharger 8, an intercooler 9, an intake throttle 10, and an intake pressure sensor 11 are arranged. Further, an atmospheric pressure sensor 12 is arranged outside the intake pipe 2.

The compressor 8a is connected to a turbine 8b disposed in the exhaust pipe 3, rotates by the rotational force of the turbine 8b rotated by exhaust pressure, and supercharges the air flowing through the intake pipe 2.
Intercooler 9 is disposed between intake manifold 2a and compressor 8a, and cools air flowing through intake pipe 2.

The intake throttle 10 is arranged on the upstream side of the intake manifold 2a in the intake pipe 2, and opens and closes the intake pipe 2 to adjust the opening degree. The intake throttle 10 can be constructed from, for example, a butterfly valve.

The intake pressure sensor 11 is arranged in the intake manifold 2a and detects the intake pressure of the engine 1.
The atmospheric pressure sensor 12 is placed in an atmospheric pressure environment and detects atmospheric pressure.

The exhaust pipe 3 is formed to extend outward from the engine 1, and discharges exhaust gas exhausted from the engine 1 to the outside. The exhaust pipe 3 has an exhaust manifold 3a. The exhaust manifold 3a is connected to the engine 1 at the base end of the exhaust pipe 3, collects exhaust gas discharged from each cylinder of the engine 1, and guides it to the exhaust pipe 3.

The EGR pipe 4 is arranged to connect between the intake manifold 2a and the exhaust manifold 3a, and recirculates a portion of the exhaust gas (EGR gas) in the exhaust pipe 3 to the intake pipe 2. The EGR pipe 4 is provided with an EGR cooler 4a and an EGR valve 4b. The EGR cooler 4a cools EGR gas. Further, the EGR valve 4b adjusts the flow rate of EGR gas that is recirculated through the EGR pipe 4.

The engine control section 5 controls the engine 1, and is connected to the engine 1, the intake throttle 10, and the acquisition section 13 of the abnormality determination device 6, respectively. The engine control unit 5 receives, for example, the intake pressure detected by the intake pressure sensor 11, the atmospheric pressure detected by the atmospheric pressure sensor 12, the driver's operation information, etc., and controls the intake pipe 2 based on these information. The flow rate of circulating air, the amount of fuel injection, the rotation speed of the engine 1, etc. are controlled.

The abnormality determination device 6 includes an acquisition section 13 and a determination section 14. The acquisition section 13 is connected to a determination section 14, and this determination section 14 is connected to the notification section 7. Further, the acquisition unit 13 is connected to the intake pressure sensor 11 and the atmospheric pressure sensor 12, respectively.

The acquisition unit 13 acquires the intake pressure from the intake pressure sensor 11 and also acquires the atmospheric pressure from the atmospheric pressure sensor 12. Further, the acquisition unit 13 acquires control information of the engine 1 and opening degree information of the intake throttle 10 from the engine control unit 5. Here, the control information includes, for example, information regarding load operation such as the rotational speed of the engine 1 and the amount of fuel to be injected. Load operation refers to operation in which the engine 1 is generating torque at a rotation speed higher than the idle rotation speed. Further, the opening degree information of the intake throttle 10 includes information indicating the opening degree of the intake throttle 10 (the degree to which the intake pipe 2 is opened), that is, control information for opening and closing the intake throttle 10.

The determination unit 14 determines whether the intake pressure sensor 11 has come off the intake pipe 2 based on the magnitude of the intake pressure acquired by the acquisition unit 13 when the engine 1 is operated under load.

If the determination unit 14 determines from the OBD that the intake pressure sensor 11 is disconnected, the notification unit 7 notifies that the intake pressure sensor 11 is disconnected. The notification section 7 can include a speaker, a display section, and the like.

Note that the functions of the engine control section 5, abnormality determination device 6, and notification section 7 can also be realized by a computer program. For example, a reading device of a computer reads a program for realizing the functions of the engine control section 5, abnormality determination device 6, and notification section 7 from a recording medium on which the program is recorded, and stores the program in a storage device. Then, the CPU (Central Processing Unit) copies the program stored in the storage device to the RAM (Random Access Memory), and sequentially reads and executes the instructions included in the program from the RAM, thereby causing the engine control unit 5, The functions of the abnormality determination device 6 and the notification section 7 can be realized.

Next, the operation of this embodiment will be explained with reference to the flowchart in FIG. 2.

First, as shown in FIG. 1, the engine control section 5 controls the engine 1 to drive the vehicle. At this time, the acquisition unit 13 sequentially acquires load operation information, such as the rotation speed of the engine 1 and the fuel injection amount, from the engine control unit 5 and outputs this load operation information to the determination unit 14 . The acquisition unit 13 also acquires the opening degree information of the intake throttle 10 from the engine control unit 5 and outputs the opening degree information to the determination unit 14 . Further, the acquisition unit 13 acquires the intake pressure detected by the intake pressure sensor 11 and the atmospheric pressure detected by the atmospheric pressure sensor 12, and outputs information on the intake pressure and the atmospheric pressure to the determination unit 14.

Subsequently, in step S1, the determination unit 14 determines whether or not load operation has been performed based on the load operation information acquired by the acquisition unit 13. For example, the determination unit 14 estimates the load of the engine 1 based on the rotation speed of the engine 1 and the amount of fuel injection, and determines whether load operation is being performed when the load of the engine 1 exceeds a predetermined threshold. It is determined that there is. At this time, the predetermined threshold value can be set, for example, to a value that ensures that the intake pressure increases more than the atmospheric pressure. The determination unit 14 repeats the process of step S1 until it is determined that load operation is being performed.

If the determining unit 14 determines that load operation is being performed, the process proceeds to step S2, and determines whether the opening degree of the intake throttle 10 is larger than a predetermined value based on the opening information acquired by the acquiring unit 13. judge. The engine control unit 5 reduces the opening degree of the intake throttle 10 so as to close the intake pipe 2, for example, to increase the temperature of exhaust gas and recirculate EGR gas. The determining unit 14 repeats the processing of steps S1 and S2 until it is determined that the opening degree of the intake throttle 10 is larger than a predetermined value based on the opening degree information from the engine control unit 5.

Generally, when the engine 1 is operated under load, the intake pressure detected by the intake pressure sensor 11 increases significantly. At this time, if the intake pressure sensor 11 is detached from the intake manifold 2a, the intake pressure detected by the intake pressure sensor 11 does not increase even during load operation and indicates, for example, atmospheric pressure.

Therefore, if the determining unit 14 determines in step S2 that the opening degree of the intake throttle 10 is larger than the predetermined value, the process proceeds to step S3, where the intake pressure of the intake pressure sensor 11 acquired by the acquiring unit 13 is almost equal to atmospheric pressure. Determine whether they show the same size.

For example, the determination unit 14 sets a predetermined reference range (range near atmospheric pressure) based on atmospheric pressure, and if the intake pressure detected by the intake pressure sensor 11 falls within the predetermined reference range, the determination unit 14 determines that the intake pressure is within the predetermined reference range. can be determined to be approximately the same magnitude as atmospheric pressure. At this time, the determination unit 14 sets a predetermined reference range based on the atmospheric pressure of the atmospheric pressure sensor 12 acquired by the acquisition unit 13, and indicates that the intake pressure of the intake pressure sensor 11 is approximately the same magnitude as the atmospheric pressure. It can be determined whether or not. If the intake pressure measured by the intake pressure sensor 11 does not fall within the predetermined reference range, the determination unit 14 determines that the intake pressure measured by the intake pressure sensor 11 is different from atmospheric pressure, and proceeds to step S4. It is determined that the intake pressure sensor 11 has not come off the intake manifold 2a.

On the other hand, if the intake pressure measured by the intake pressure sensor 11 falls within the predetermined reference range, the determination unit 14 determines that the intake pressure measured by the intake pressure sensor 11 is approximately the same as the atmospheric pressure, and proceeds to step S5. It is determined that the atmospheric pressure sensor 11 is disconnected from the intake manifold 2a.

In this way, the determination unit 14 determines whether the intake pressure sensor 11 has come off from the intake manifold 2a based on the magnitude of the intake pressure acquired by the acquisition unit 13 when the engine 1 is operated under load. . Therefore, it can be determined during load operation when the intake pressure in the intake pipe 2 increases significantly, and it is possible to reliably determine whether the intake pressure sensor 11 has come off from the intake manifold 2a.

Further, the determination unit 14 performs determination when the opening degree of the intake throttle 10 acquired by the acquisition unit 13 is larger than a predetermined value. For example, if the opening degree of the intake throttle 10 is reduced in order to raise the temperature of exhaust gas, the intake pressure will be significantly reduced. If the determination is made in an environment where the intake pressure significantly decreases as described above, there is a risk that a decrease in the intake pressure caused by the intake throttle 10 may be mistakenly determined as a decrease in the intake pressure due to the intake pressure sensor 11 coming off. Therefore, the determining unit 14 can suppress erroneous determinations by making a determination when the opening degree of the intake throttle 10 is larger than a predetermined value, and can more reliably determine whether the intake pressure sensor 11 is disconnected. . Note that the predetermined value can be set, for example, based on the opening degree of the intake throttle 10 at which the intake pressure decreases to near atmospheric pressure.

Further, the determination unit 14 determines that the intake pressure sensor 11 is disconnected when the intake pressure of the intake pressure sensor 11 is approximately the same as the atmospheric pressure. At this time, if the determination is made based on a change in the difference between the intake pressure detected by the intake pressure sensor 11 and the atmospheric pressure detected by the atmospheric pressure sensor 12, for example, if the intake pressure in the intake pipe 2 suddenly changes. In addition, there is a possibility that it may be mistakenly determined that the intake pressure sensor 11 is disconnected. Therefore, the determining unit 14 can more reliably determine whether the intake pressure sensor 11 is disconnected by making the determination based on whether the intake pressure of the intake pressure sensor 11 is approximately the same as the atmospheric pressure. .

Further, since the determining unit 14 determines the magnitude of the intake pressure of the intake pressure sensor 11 based on the atmospheric pressure detected by the atmospheric pressure sensor 12, the standard can be changed according to the actual atmospheric pressure. Therefore, even if the atmospheric pressure changes due to the vehicle traveling on a highland, for example, it is possible to determine with high accuracy whether the intake pressure sensor 11 is disconnected.

Here, it is preferable that the determination unit 14 performs the determination when the engine 1 is continuously operated under load for a predetermined period of time or more. At this time, the predetermined time can be set, for example, to a time during which the intake pressure in the intake pipe 2 is stably maintained at a value greater than atmospheric pressure. Thereby, the determination unit 14 can make a determination while the intake pressure in the intake pipe 2 is stable, and therefore can more reliably determine whether the intake pressure sensor 11 has come off.

Further, it is preferable that the determination unit 14 performs the determination when the opening degree of the intake throttle 10 continues for a predetermined period of time or more and is larger than a predetermined value. At this time, the predetermined time can be set, for example, to a time during which the intake throttle 10 stably maintains a predetermined opening degree. Thereby, the determination unit 14 can make a determination while the intake pressure in the intake pipe 2 is stable, and therefore can more reliably determine whether the intake pressure sensor 11 has come off.

In this manner, when determining in step S5 that the intake pressure sensor 11 is removed from the intake manifold 2a, the determination unit 14 outputs the determination result to the notification unit 7. Then, in step S6, the notification unit 7 notifies that the intake pressure sensor 11 has come off.

The notification unit 7 can notify that the intake pressure sensor 11 has come off, for example, using an OBD device installed in the vehicle. Further, the notification section 7 can be placed at a dealer that maintains the vehicle, and the notification section 7 can be installed at a dealer or the like that maintains the vehicle, and the notification section 7 can notify the maintenance worker of the disconnection of the intake pressure sensor 11 based on the determination result transmitted from the determination section 14 via a communication section (not shown). can be notified.

According to the present embodiment, the determination unit 14 makes a determination based on the magnitude of the intake pressure acquired by the acquisition unit 13 when the engine 1 is operated under load. It is possible to reliably determine whether the sensor 11 has come off.

Note that in the above embodiment, the determining unit 14 determines whether the intake pressure sensor 11 is disconnected using the atmospheric pressure detected by the atmospheric pressure sensor 12; It is sufficient if the determination can be made based on, and is not limited to this. For example, the determination unit 14 can store a predetermined reference atmospheric pressure in advance, and determine whether the intake pressure sensor 11 is disconnected based on the reference atmospheric pressure.

Further, in the above embodiment, the determining unit 14 determines whether the intake pressure sensor 11 has come off from the intake manifold 2a, but it is sufficient if it can determine whether the intake pressure sensor 11 has come off from the intake pipe 2. It is not limited to. That is, the determination unit 14 can also determine whether the intake pressure sensor 11 disposed in a location other than the intake manifold 2a in the intake pipe 2 has come off.

Further, in the above embodiment, the determining unit 14 determines whether the intake pressure sensor 11 is disconnected based on whether the intake pressure acquired by the acquiring unit 13 is approximately the same as atmospheric pressure. It is only necessary that the determination can be made based on the magnitude of the intake pressure obtained in , and is not limited to this. For example, the determination unit 14 can also determine whether the intake pressure sensor 11 is disconnected based on the difference between the intake pressure and atmospheric pressure acquired by the acquisition unit 13.

Furthermore, in the above embodiment, the abnormality determination device 6 is placed in the vehicle, but it is not limited to this as long as it can determine whether the intake pressure sensor 11 has come off the intake pipe 2. For example, the abnormality determination device 6 can be placed in a ship, an industrial machine, or a factory equipped with a stationary internal combustion engine.

In addition, the above-mentioned embodiments are merely examples of implementation of the present invention, and the technical scope of the present invention should not be construed as limited by these. be. That is, the present invention can be implemented in various forms without departing from its gist or main features. For example, the disclosure regarding the shape, number, etc. of each part described in the above embodiment is merely an example, and can be implemented with appropriate changes.

The abnormality determination device according to the present disclosure can be used as a device for determining abnormality of an intake pressure sensor.

1 Engine 2 Intake pipe 2a Intake manifold 3 Exhaust pipe 3a Exhaust manifold 4 EGR pipe 4a EGR cooler 4b EGR valve 5 Engine control section 6 Abnormality determination device 7 Notification section 8 Turbocharger 8a Compressor 8b Turbine 9 Intercooler 10 Intake throttle 11 Intake pressure Sensor 12 Atmospheric pressure sensor 13 Acquisition unit 14 Judgment unit

Claims

an acquisition unit that acquires intake pressure from an intake pressure sensor placed in the intake pipe;
An abnormality determination device comprising: a determination unit that determines whether the intake pressure sensor is disconnected from the intake pipe based on the magnitude of the intake pressure acquired by the acquisition unit when the engine is operated under load.
The acquisition unit further acquires an opening degree of an intake throttle arranged in the intake pipe so as to sandwich the intake pressure sensor between the acquisition unit and the engine;
The abnormality determining device according to claim 1, wherein the determining unit performs the determination when the engine is operated under load and the opening degree of the intake throttle acquired by the acquiring unit is larger than a predetermined value.
The abnormality determination device according to claim 1, wherein the determination unit determines that the intake pressure sensor is off when the intake pressure acquired by the acquisition unit shows approximately the same magnitude as atmospheric pressure.
The abnormality determination device according to claim 1, wherein the determination unit performs the determination when the engine is continuously operated under load for a predetermined period of time or more.