JP2018021506A - Abnormality detector, abnormality detection method, and abnormality detection system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve abnormality detection accuracy for a cylinder based on a correction amount of a fuel injection amount.SOLUTION: An abnormality detector 1 includes: an acquisition unit 141 configured to acquire a correction amount of each fuel injection amount of plural cylinders 25 with an engine 21 made into a predetermined state; a storage unit 13 configured to store in time-series the plural correction amounts acquired by the acquisition unit 141 in association with the respective cylinders 25; and a determination unit 142 configured to determine whether abnormality occurs in any of the plural cylinders 25, on the basis of a variation pattern of the plural correction amount.SELECTED DRAWING: Figure 3

Description

  The present invention relates to an abnormality detection device, an abnormality detection method, and an abnormality detection system that detect an abnormality of an engine.

  2. Description of the Related Art Conventionally, in a vehicle engine having a plurality of cylinders, a technique for correcting the fuel injection amount in each cylinder is known in order to reduce the influence of variation among the cylinders. Patent Document 1 discloses an apparatus that determines that an abnormality has occurred when the deviation between the correction amount of the fuel injection amount of each cylinder and the initial correction amount exceeds a predetermined range.

JP-A-9-177487

  The correction amount of the fuel injection amount varies depending on various factors. Therefore, if it is determined that an abnormality has occurred due to the deviation between the correction amount used and the initial correction amount exceeding a predetermined range, as in the prior art, fluctuations in the correction amount are temporarily changed. In spite of the fact that no abnormality has occurred, there has been a problem that it may be erroneously determined that an abnormality has occurred.

  Therefore, the present invention has been made in view of these points, and provides an abnormality detection device, an abnormality detection method, and an abnormality detection system that can improve the abnormality detection accuracy of a cylinder based on the correction amount of the fuel injection amount. For the purpose.

  An abnormality detection device according to a first aspect of the present invention is an abnormality detection device for detecting an abnormality of an engine having a plurality of cylinders mounted on a vehicle, wherein the plurality of cylinders while the engine is in a predetermined state. An acquisition unit that acquires a correction amount of each fuel injection amount, a storage unit that stores a plurality of correction amounts acquired by the acquisition unit in association with each of the cylinders, and a change in the plurality of correction amounts And a determination unit that determines whether an abnormality has occurred in any of the plurality of cylinders based on the pattern.

  The determination unit determines, for example, that an abnormality has occurred in the cylinder corresponding to the correction amount when the correction amount is equal to or greater than a predetermined upper limit value or lower limit value for a predetermined number of times within a predetermined period. To do.

  Whether the abnormality has occurred by comparing the maximum value or the minimum value of the correction amount in the idle state within a period from when the engine is started to when it is stopped with the upper limit value or the lower limit value. It may be determined whether or not.

  The determination unit may determine whether an abnormality has occurred by comparing a plurality of the maximum values or minimum values in the plurality of periods with the upper limit value or the lower limit value.

  The determination unit estimates the maximum value and the minimum value based on a plurality of change states of the correction amount, and determines whether an abnormality has occurred based on the estimated maximum value and the minimum value. May be.

  An abnormality detection method according to a second aspect of the present invention is a method for detecting an abnormality of an engine having a plurality of cylinders mounted on a vehicle, wherein each of the plurality of cylinders while the engine is in a predetermined state is detected. Corresponding to the step of acquiring the correction amount of the fuel injection amount, the step of storing the plurality of correction amounts acquired by the acquisition unit in the storage unit in association with the time when the correction amount was used, and the plurality of times Determining whether an abnormality has occurred in any of the plurality of cylinders by comparing the plurality of correction amounts with a reference value.

  An abnormality detection system according to a third aspect of the present invention is an abnormality detection system including an engine mounted on a vehicle and an abnormality detection device that detects an abnormality of the engine, and the engine includes a plurality of cylinders. A control unit that corrects the fuel injection amount, and a communication unit that transmits correction amount data indicating the correction amount of the fuel injection amount to the abnormality detection device via a wireless communication line, and the abnormality detection device The acquisition unit that acquires the correction amount data corresponding to each of the plurality of cylinders while the engine is in a predetermined state, and the plurality of correction amounts acquired by the acquisition unit are associated with each of the cylinders. And a determination unit that determines whether or not an abnormality has occurred in any of the plurality of cylinders based on the change patterns of the plurality of correction amounts.

  According to the present invention, the cylinder abnormality detection accuracy based on the fuel injection amount correction amount can be improved.

It is a figure which shows the structure of the abnormality detection system which concerns on this embodiment. It is a figure which shows the structure of the engine system of the vehicle which concerns on this embodiment. It is a schematic diagram which shows the mode of the change of the correction amount after starting an engine. It is a figure which shows the structure of an abnormality detection apparatus. It is a figure for demonstrating the method a determination part determines with abnormality having generate | occur | produced. It is a flowchart of the operation | movement which an abnormality detection apparatus detects abnormality of a cylinder.

  FIG. 1 is a diagram illustrating a configuration of an abnormality detection system S according to the present embodiment. The abnormality detection system S is a system that detects an abnormality of the vehicle T in conjunction with the abnormality detection device 1 and the vehicle T. The abnormality detection device 1 is installed in a data collection center C that collects data indicating various vehicle T states. The abnormality detection device 1 is connected to a plurality of vehicles T via wireless communication lines, and receives data indicating the state of the vehicle T from each vehicle T at a predetermined time interval. The abnormality detection device 1 detects an abnormality of the vehicle T based on various data received from the vehicle T.

  The abnormality detection apparatus 1 is connected to a computer installed in a management base station M that manages the vehicle T via a network (for example, the Internet). The management base station M is a company that owns the vehicle T or a company that maintains the vehicle T, for example. When the employee of the management base station M receives a notification that an abnormality has occurred in the vehicle T from the abnormality detection device 1, it notifies the driver of the vehicle T that an abnormality has occurred, By doing so, serious accidents can be prevented.

  The abnormality detection system S can identify the cylinder in which an abnormality has occurred based on the correction value of the fuel injection amount of each cylinder of the vehicle T. First, the configuration of the engine system including the cylinders of the vehicle T will be described.

[Configuration of engine system 2]
FIG. 2 is a diagram illustrating a configuration of the engine system 2 of the vehicle T according to the present embodiment. The engine system 2 of the present embodiment has a multi-cylinder (four cylinders in the present embodiment) diesel engine. The engine system 2 includes an engine 21, an intake passage 22 and an exhaust passage 23 connected to the engine 21, a common rail 24, four cylinders 25 (25a to 25d), a fuel injection valve (injector) 26, a cylinder An internal pressure sensor 27, a crank angle sensor 28, an ECU (Electronic Control Unit) 29 that functions as a control unit, and a communication unit 30 are included.

The common rail 24 stores the fuel injected from the fuel injection valve 26 to each cylinder 25 in a high pressure state.
The cylinder 25 is assigned a cylinder number for identifying each cylinder 25. Cylinder numbers 01 to 04 are assigned to the cylinders 25a to 25d, respectively.

  A fuel injection valve 26 and an in-cylinder pressure sensor 27 are provided for each cylinder 25. The fuel injection valve 26 injects an amount of fuel determined based on the control of the ECU 29 into the cylinder 25. The in-cylinder pressure sensor 27 detects the pressure inside the cylinder 25, that is, the in-cylinder pressure, and notifies the ECU 29 of the detected in-cylinder pressure. The crank angle sensor 28 detects the rotation angle of the crankshaft and the engine speed, and notifies the ECU 29 of the detected speed.

  The ECU 29 includes a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), an input port, an output port, and the like. The ECU 29 controls the amount of fuel injected from the fuel injection valve 26 of each cylinder 25. Further, the ECU 29 corrects the fuel injection amount that is determined based on the engine operating state in order to reduce the variation in rotational fluctuation between the cylinders 25 and the variation in the combustion state.

  Specifically, the ECU 29 determines the fuel injection amount corresponding to the engine speed detected by the crank angle sensor 28 based on the relationship between the engine speed and the fuel injection amount that are determined in advance corresponding to the accelerator opening. decide. At this time, the ECU 29 detects the variation amount of the rotation variation of each cylinder 25 and corrects the fuel injection amount of each cylinder 25 based on the variation amount of the rotation variation. However, the amount by which the ECU 29 can correct the fuel injection amount has an upper limit value and a lower limit value. When correction exceeding the upper limit value or the lower limit value is necessary, the correction amount is set to the upper limit value or the lower limit value.

  The ECU 29 stores the maximum value or the minimum value of the correction amount of each cylinder 25 while the engine 21 is in an idle state in association with the cylinder number in the RAM from when the engine 21 is started to when it is stopped. For example, the ECU 29 periodically stores the correction amount after the correction amount is stabilized after the engine 21 is started in the RAM.

  FIG. 3 is a schematic diagram showing how the correction amount changes after the engine 21 is started. The correction amount varies depending on the internal temperature of the engine 21, and for example, as shown in FIG. 3, the correction amount becomes stable after gradually increasing as the time since the engine 21 is started. The correction amount at the stable time is substantially equal to the maximum value or the minimum value of the correction amount from when the engine 21 is started to when it is stopped.

  In the example shown in FIG. 3, the correction amount of the cylinder 25a is gradually increased, and the correction value a is the maximum value. In the cylinder 25b, the correction amount gradually increases, and the correction value b becomes the maximum value. In the cylinder 25c, the correction amount gradually decreases, and the correction value c is the minimum value. In the cylinder 25d, the correction amount gradually decreases, and the correction value d is the minimum value.

  The ECU 29 stores the maximum value and the minimum value specified after being stabilized in this manner in the RAM. The ECU 29 may store the correction amount after a predetermined time has elapsed from the start of the engine 21 in the RAM as the maximum value or the minimum value.

  The communication unit 30 is a wireless communication unit for transmitting and receiving data via a wireless communication line. The communication unit 30 transmits various data acquired from the ECU 29 to the abnormality detection device 1 and receives various data transmitted by the abnormality detection device 1 and notifies the ECU 29 of the various data. For example, the communication unit 30 detects an abnormality at predetermined time intervals in association with correction amount data indicating the correction amount applied to the fuel injection amount of each cylinder 25 by the ECU 29 in association with the cylinder number for specifying the cylinder 25. Transmit to device 1.

[Configuration of Abnormality Detection Device 1]
FIG. 4 is a diagram illustrating the configuration of the abnormality detection device 1.
The abnormality detection device 1 includes a first communication unit 11, a second communication unit 12, a storage unit 13, and a control unit 14. The control unit 14 includes an acquisition unit 141, a determination unit 142, and an abnormality notification unit 143.

  The first communication unit 11 is a wireless communication unit for transmitting and receiving data to and from the engine system 2 via a wireless communication line. The 1st communication part 11 receives the electromagnetic wave containing various data, such as correction amount data, from the some vehicle T registered previously, for example via the computer of a packet communication network. The first communication unit 11 extracts correction amount data included in the received radio wave, and inputs the correction amount data to the acquisition unit 141.

  The second communication unit 12 is a communication controller for transmitting and receiving data to and from the computer of the management base station M via the Internet. When the determination unit 142 detects an abnormality in the cylinder 25 of the vehicle T, the second communication unit 12 transmits a message notifying the abnormality to the computer of the management base station M that manages the vehicle T.

  The storage unit 13 is a storage medium including a ROM, a RAM, a hard disk, and the like. The storage unit 13 stores a program executed by the control unit 14. In addition, the storage unit 13 stores the correction amount data transmitted from the vehicles T in time series in association with the identification information, the cylinder number, and the correction amount unique to each vehicle T.

  In the storage unit 13, the determination unit 142 stores an upper limit value and a lower limit value of the correction amount of the cylinder 25. Since the upper limit value and the lower limit value of the correction amount are different for each vehicle type of the vehicle T, the storage unit 13 stores the upper limit value and the lower limit value of the correction amount in association with the vehicle type of the vehicle T, for example.

The control unit 14 is, for example, a CPU, and functions as the acquisition unit 141, the determination unit 142, and the abnormality notification unit 143 by executing a program stored in the storage unit 13.
The acquisition unit 141 acquires correction amount data used by the ECU 29 at a plurality of different times and indicating the correction amount of the fuel injection amount when the engine 21 is in a predetermined state via the first communication unit 11. The acquisition unit 141 acquires correction amount data indicating the maximum value or the minimum value of the correction amount used in the idle state from when the engine 21 of the vehicle T is started to when it is stopped.

The acquisition unit 141 acquires correction data indicating the maximum value or the minimum value of the correction amount for each predetermined period, and causes the storage unit 13 to store a plurality of correction amount data acquired for each predetermined period in time series.
The predetermined period is, for example, a period from when the engine 21 is started to when it is stopped.

  The determination unit 142 reads a plurality of correction amount data stored in the storage unit 13 and determines whether or not an abnormality has occurred in any of the plurality of cylinders 25 based on a plurality of correction amount change patterns. . Specifically, when the correction amount has reached a predetermined upper limit value or lower limit value for a predetermined number of times or more within a predetermined period, an abnormality has occurred in the cylinder 25 corresponding to this correction amount. Is determined. For example, the determination unit 142 compares the maximum value or the minimum value of the correction amount in the idle state within a period from when the engine 21 is started to when it is stopped, to determine whether an abnormality has occurred. Determine whether.

  FIG. 5 is a diagram for describing a method in which the determination unit 142 determines that an abnormality has occurred. FIG. 5 shows an example of correction amount data of each cylinder 25 acquired by the acquisition unit 141 from the vehicle T. The horizontal axis in FIG. 5 indicates the number of days that have elapsed since the start of recording the correction amount data. The vertical axis indicates the correction amount, where a positive number indicates a correction amount that increases the fuel injection amount, and a negative number indicates a correction amount that decreases the fuel injection amount.

  In FIG. 5, the correction amount of the cylinder 25a starts to increase from the 14th day, and the day when the upper limit value is 15 is increased after the 18th day. The determination unit 142 determines that an abnormality has occurred in the cylinder 25a because the correction amount is 15 in 13 days out of 20 days from the 19th day to the 39th day.

  The rule of the change pattern that the determination unit 142 determines that an abnormality has occurred is arbitrary, and it is determined that an abnormality has occurred when the correction amount is continuously equal to the upper limit value or the lower limit value for a predetermined number of times or more. Also good. The determination unit 142 may determine that an abnormality has occurred when the average value of the correction amounts within a predetermined period is within a predetermined value from the upper limit value or the lower limit value.

  When the determination unit 142 determines that an abnormality has occurred in the cylinder 25, the abnormality notification unit 143 notifies the computer of the management base station M that an abnormality has occurred. Specifically, the abnormality notification unit 143 includes the identification information of the vehicle T in which the abnormality has occurred, the cylinder number of the cylinder 25 in which the abnormality has occurred, and the address of the computer of the management base station M that manages the vehicle T. An abnormality notification message including the fact that an abnormality has occurred is created and transmitted via the second communication unit 12 to notify the computer of the management base station M that an abnormality has occurred.

[Flowchart of abnormality detection operation]
FIG. 6 is a flowchart of an operation in which the abnormality detection device 1 detects an abnormality in the cylinder 25.
First, the acquisition unit 141 acquires correction amount data transmitted from the vehicle T (S11). Whenever the acquisition unit 141 acquires the correction amount data, the acquisition unit 141 associates the correction amount data with the identification information and the cylinder number of the vehicle T and stores them in the storage unit 13 (S12).

  In response to the acquisition unit 141 acquiring new correction amount data, the determination unit 142 identifies a change pattern of a plurality of correction amount data acquired by the acquisition unit 141 within the most recent predetermined period (S13). Then, the determination unit 142 determines whether or not the identified change pattern is in the normal range (S14).

  When the change pattern is in the normal range as in the cylinders 25b, 25c, and 25d shown in FIG. 5 (YES in S14), the determination unit 142 determines that no abnormality has occurred and proceeds to step S11. Return and wait until the next intake air amount data is transmitted. When the change pattern is not in the normal range as in the cylinder 25a shown in FIG. 5 (NO in S14), the determination unit 142 determines that an abnormality has occurred in the cylinder 25a (S15).

  Here, the determination unit 142 determines whether the level of abnormality is a level that requires emergency response or a level that does not require emergency response. The level is notified to the abnormality notification unit 143 (S16). When the abnormality notification unit 143 receives a notification of the occurrence of an urgent abnormality (for example, an abnormality that hinders driving), the abnormality notification unit 143 notifies both the management base station M and the vehicle T that the abnormality has occurred ( S17). The abnormality notification unit 143 may determine that the abnormality is urgent when the frequency at which the correction amount matches the upper limit value or the lower limit value is equal to or greater than a predetermined value. When the abnormality notification unit 143 receives a notification of occurrence of an abnormality that is not urgent (for example, an abnormality in which component deterioration is estimated), the abnormality notification unit 143 notifies only the management base station M that the abnormality has occurred ( S18).

[Modification 1]
In the above description, the ECU 29 of the vehicle T specifies the maximum value and the minimum value of the correction amount in the idle state from when the engine 21 is started to when it is stopped. The subject specifying the value is arbitrary. For example, the ECU 29 transmits all correction amount data to the abnormality detection device 1, and the acquisition unit 141 of the abnormality detection device 1 acquires correction amount data indicating the correction amount used in a state other than the engine idle state. May be.

  In this case, the acquisition unit 141 acquires information indicating the engine state in association with the correction amount data, such as information indicating the engine speed and the accelerator opening. The acquisition unit 141 extracts correction amount data used in the idle state from the acquired correction amount data, and stores the extracted correction amount data in the storage unit 13 in time series. By doing in this way, the abnormality detection apparatus 1 can detect abnormality based on the correction amount data plotted as shown in FIG.

  In addition, when the engine 21 stops the engine 21 for a short time after the vehicle T starts, the engine 21 stops before the correction amount is stabilized, and the maximum value and the minimum value may not be specified. In such a case, the determination unit 142 estimates the maximum value and the minimum value based on the change states of the plurality of correction amounts after the engine 21 is started, and performs an abnormality based on the estimated maximum value and minimum value. You may determine the presence or absence of.

[Modification 2]
In the example shown in FIG. 5, the horizontal axis is the number of days that have elapsed since the start of the recording of the correction amount data, but the unit of the horizontal axis is arbitrary. For example, the abnormality detection device 1 plots one correction amount data within one period from when the engine 21 is started to when it stops, with the period from when the engine 21 is started to when it stops as one unit on the horizontal axis. May be.

[Effects of the abnormality detection device 1 of the present embodiment]
As described above, the vehicle T transmits correction amount data indicating the correction amount of the fuel injection amount of each cylinder 25 when the engine 21 is in an idle state to the abnormality detection device 1. Then, the abnormality detection device 1 associates each of the plurality of correction amount data acquired by the acquisition unit 141 with each of the cylinders 25 and stores the correction amount data in the storage unit 13 in time series, and the determination unit 142 makes a change pattern of the plurality of correction amounts. Based on this, it is determined whether or not an abnormality has occurred in any of the plurality of cylinders 25. By doing so, the determination unit 142 eliminates the influence of the temporary variation in the correction amount of the cylinder 25 and is abnormal when the correction amount continuously reaches the upper limit value or the lower limit value. Since it can be determined, the accuracy of detecting an abnormality in the cylinder 25 is improved.

  In addition, the abnormality detection device 1 compares the maximum value or the minimum value of the correction amount in the idle state during the period from when the engine 21 is started to when it is stopped, to determine whether an abnormality has occurred. Therefore, the determination can be made based on the change in the correction amount in a state where the fuel injection amount is stable. Therefore, the accuracy of detecting an abnormality is further improved.

  Moreover, the abnormality detection apparatus 1 estimates the maximum value and the minimum value based on the change states of the plurality of correction amounts, and determines whether an abnormality has occurred based on the estimated maximum value and minimum value. By doing in this way, even if the period from starting to stopping the engine 21 is short and the correction amount is not stable, the correction amount can be used for the determination of abnormality.

<Second Embodiment>
In the first embodiment, the abnormality detection device 1 installed in the data collection center C detects an abnormality in the cylinder 25, but the vehicle T detects an abnormality that is equivalent to the abnormality detection device 1 in the first embodiment. An abnormality of the cylinder 25 in the vehicle T may be detected. In this case, when the abnormality detection device of the vehicle T detects an abnormality, the abnormality detection device of the vehicle T displays on the instrument panel that the abnormality has occurred and notifies the driver to the management base station M. Report the occurrence of an abnormality.

  As mentioned above, although this invention was demonstrated using embodiment, the technical scope of this invention is not limited to the range as described in the said embodiment. It will be apparent to those skilled in the art that various modifications or improvements can be added to the above embodiment. It is apparent from the scope of the claims that the embodiments added with such changes or improvements can be included in the technical scope of the present invention.

DESCRIPTION OF SYMBOLS 1 Abnormality detection apparatus 2 Engine system 11 1st communication part 12 2nd communication part 13 Memory | storage part 14 Control part 21 Engine 22 Intake passage 23 Exhaust passage 24 Common rail 25 Cylinder 26 Fuel injection valve 27 In-cylinder pressure sensor 28 Crank angle sensor 29 ECU
30 communication unit 141 acquisition unit 142 determination unit 143 abnormality notification unit

Claims (7)

An abnormality detection device for detecting an abnormality of an engine having a plurality of cylinders mounted on a vehicle,
An acquisition unit that acquires a correction amount of a fuel injection amount of each of the plurality of cylinders while the engine is in a predetermined state;
A storage unit that stores the plurality of correction amounts acquired by the acquisition unit in association with each of the cylinders in time series;
A determination unit that determines whether or not an abnormality has occurred in any of the plurality of cylinders based on the plurality of correction amount change patterns;
An anomaly detection device. The determination unit determines that an abnormality has occurred in the cylinder corresponding to the correction amount when the correction amount is greater than or equal to a predetermined upper limit value or less than a lower limit value over a predetermined number of times within a predetermined period.
The abnormality detection device according to claim 1. Whether the abnormality has occurred by comparing the maximum value or the minimum value of the correction amount in the idle state within a period from when the engine is started to when it is stopped with the upper limit value or the lower limit value. Determine whether or not
The abnormality detection device according to claim 2. The determination unit determines whether or not an abnormality has occurred by comparing a plurality of the maximum values or minimum values within the plurality of periods with the upper limit value or the lower limit value.
The abnormality detection device according to claim 3. The determination unit estimates the maximum value and the minimum value based on a plurality of change states of the correction amount, and determines whether an abnormality has occurred based on the estimated maximum value and the minimum value. To
The abnormality detection device according to claim 3 or 4. A method for detecting an abnormality in an engine having a plurality of cylinders mounted on a vehicle,
Obtaining a fuel injection amount correction amount for each of the plurality of cylinders while the engine is in a predetermined state;
Storing the obtained plurality of correction amounts in a storage unit in association with the time when the correction amount was used;
Determining whether an abnormality has occurred in any of the plurality of cylinders by comparing the plurality of correction amounts corresponding to a plurality of times with a reference value;
An abnormality detection method comprising: An abnormality detection system comprising an engine mounted on a vehicle and an abnormality detection device that detects abnormality of the engine,
The engine is
A control unit for correcting the fuel injection amount of each of the plurality of cylinders;
A communication unit that transmits correction amount data indicating a correction amount of the fuel injection amount to the abnormality detection device via a wireless communication line;
Have
The abnormality detection device is:
An acquisition unit that acquires the correction amount data corresponding to each of the plurality of cylinders while the engine is in a predetermined state;
A storage unit that stores the plurality of correction amounts acquired by the acquisition unit in association with each of the cylinders in time series;
A determination unit that determines whether or not an abnormality has occurred in any of the plurality of cylinders based on the plurality of correction amount change patterns;
Having an anomaly detection system.

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