JP2007198290A - Vehicle abnormality diagnosis device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vehicle malfunction diagnosis device capable of properly reflecting malfunction in control to prevent its occurrence while reducing the storage amount of data to be used for estimating the causes of vehicle malfunction. <P>SOLUTION: In the vehicle malfunction diagnoses device, a time difference data calculating means calculates time difference data for each of a plurality of sensors and a storage means stores the time difference data. An updating means updates the time difference data stored in the storage means. Thus, the storage amount of data to be used for estimating the causes of malfunction can be reduced. A malfunction cause estimating means estimates the causes of malfunction in accordance with the time difference data when the occurrence of malfunction is determined. A control reflecting means reflects the malfunction in control to prevent its reoccurrence. Thus, the further occurrence of malfunction can be properly suppressed. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a vehicle abnormality diagnosis apparatus that acquires data from a plurality of sensors provided in a vehicle and diagnoses an abnormality occurring in the vehicle.

  Conventionally, detection values of various sensors provided in the vehicle are acquired, and failure diagnosis in the vehicle is performed based on the detection values. For example, Patent Document 1 describes a technique for analyzing a failure location by comparing data with a reference value. Patent Document 2 describes a technique for acquiring not only the detection value of a sensor but also information outside the vehicle, and analyzing the cause of an event that has occurred in the vehicle based on these information. In addition, Patent Documents 3 and 4 propose techniques for performing vehicle fault diagnosis.

JP 2005-14743 A JP 2002-106412 A JP 2002-106411 A JP 10-138780 A

  However, since the techniques described in Patent Documents 1 to 4 described above continue to store data acquired until a failure occurs, a large-capacity memory is required and the memory is loaded. There was a case. In addition, the techniques described in Patent Documents 1 to 4 described above do not take subsequent measures against failures.

  The present invention has been made to solve the above-described problems, and appropriately reduces the storage amount of data used for estimating the cause of an abnormality that has occurred in a vehicle, so that no abnormality occurs. An object of the present invention is to provide a vehicle abnormality diagnosis device that can be reflected in control.

  In one aspect of the present invention, a vehicle abnormality diagnosis apparatus that acquires data from a plurality of sensors provided in a vehicle and diagnoses an abnormality that has occurred in the vehicle based on the data is provided for each of the plurality of sensors. Time difference data calculation means for calculating time difference data between data acquired at present and data acquired a predetermined time ago, storage means for storing the time difference data, and each time difference data is calculated And updating means for updating the time difference data stored in the storage means with the calculated new time difference data.

  The vehicle abnormality diagnosis apparatus is an apparatus that acquires data from a plurality of sensors provided in the vehicle and diagnoses an abnormality occurring in the vehicle based on the acquired data. The time difference data calculation means calculates time difference data between the currently acquired data and the data acquired before a predetermined time for each of the plurality of sensors, and the storage means stores the time difference data. Then, the updating means updates the time difference data stored in the storage means with the calculated new time difference data every time the time difference data is calculated. Thereby, according to the above-described vehicle abnormality diagnosis device, it is possible to reduce the storage amount of data used for estimating the cause of abnormality and the like.

  In one aspect of the above vehicle abnormality diagnosis apparatus, when it is determined that an abnormality has occurred in the vehicle, an abnormality determination unit that determines whether or not an abnormality has occurred in the vehicle, An abnormality cause estimating means for estimating the cause of the abnormality based on the time difference data stored in the storage means, and a control for preventing the abnormality from occurring again based on the cause of the abnormality estimated by the abnormality cause estimating means. And a control reflecting means for reflecting the data.

  In this aspect, the abnormality determination unit determines whether or not an abnormality has occurred in the vehicle, and the abnormality cause estimation unit determines the time difference stored in the storage unit when it is determined that an abnormality has occurred. Estimate the cause of the abnormality based on the data. In other words, the abnormality cause estimation means determines what has affected the abnormality in the driving situation. Then, the control reflecting means reflects to the control so that the abnormality does not occur again based on the cause of the abnormality estimated by the abnormality cause estimating means. According to the vehicle abnormality diagnosis apparatus described above, since the reflection to the control according to the estimated cause of the abnormality is performed, it is possible to appropriately suppress the future occurrence of the abnormality.

  In another aspect of the vehicle abnormality diagnosis apparatus, the update unit stops updating the time difference data when the abnormality determination unit determines that an abnormality has occurred. Thereby, it is possible to prevent the time difference data acquired when an abnormality has occurred from being rewritten and erased. That is, the time difference data acquired when an abnormality occurs can be held.

  Preferably, in the vehicle abnormality diagnosis device, the abnormality determination unit determines whether or not an engine stall has occurred, the abnormality cause estimation unit estimates the cause of the engine stall, The control reflecting means, when the abnormality cause determining means estimates that the engine stall has occurred due to a sudden change in the rotational speed of the internal combustion engine and a change in the shift position, the sudden change in the rotational speed of the internal combustion engine and the shift position in the future. When the change occurs, it is reflected in the control so that the operation for turning off the air conditioner is prohibited.

  This makes it possible to reduce the storage amount of data used for estimating the cause of engine stall while appropriately estimating the cause of engine stall (engine stop). In addition, since the control according to the cause of the engine stall can be performed in the future, it becomes possible to appropriately suppress the engine stall again.

  Preferred embodiments of the present invention will be described below with reference to the drawings.

[overall structure]
First, the configuration of the internal combustion engine according to the embodiment of the present invention will be described.

  FIG. 1 is a schematic diagram illustrating a configuration of a vehicle 100 to which the vehicle abnormality diagnosis apparatus according to the present embodiment is applied. In FIG. 1, solid arrows indicate gas flows, and broken arrows indicate input / output of signals.

  The vehicle 100 mainly includes an internal combustion engine (engine) 1 and a control unit 50. The internal combustion engine 1 includes an intake passage 3, a throttle valve 4, a fuel injection valve 5, a cylinder 6 a, an intake valve 7, an exhaust valve 8, an exhaust passage 9, and a spark plug 10. In FIG. 1, only one cylinder 6a is shown for convenience of explanation, but the internal combustion engine 1 actually has a plurality of cylinders 6a.

  Air introduced from outside passes through the intake passage 3, and the throttle valve 4 adjusts the flow rate of air passing through the intake passage 3. The air that has passed through the intake passage 3 is supplied to the combustion chamber 6b of the cylinder 6a. The fuel injected by the fuel injection valve 5 is supplied to the combustion chamber 6b. In the combustion chamber 6b, when the ignition plug 10 is ignited, the supplied air-fuel mixture is combusted. In this case, the piston 6c reciprocates by combustion, and this reciprocating motion is transmitted to the crankshaft (not shown) via the connecting rod 6d, and the crankshaft rotates. An exhaust passage 9 is connected to the internal combustion engine 1, and exhaust gas generated by combustion is discharged from the exhaust passage 9.

  An intake valve 7 and an exhaust valve 8 are provided in the combustion chamber 6 b of the internal combustion engine 1. The intake valve 7 controls conduction / interruption between the intake passage 3 and the combustion chamber 6b by opening and closing. Further, the exhaust valve 8 controls opening / closing of the exhaust passage 9 and the combustion chamber 6b by opening and closing.

  Further, vehicle 100 includes a rotation speed sensor 21, a shift position sensor 22, and an air conditioner switch 23. The rotation speed sensor 21 is a sensor that detects the rotation speed of the internal combustion engine 1, and the shift position sensor 22 is a sensor that detects the current position of the shift (gear shift). The air conditioner switch 23 is a switch for switching on and off an air conditioner (air conditioner) provided in the vehicle 100 and is operated by a driver or a passenger.

  The control unit 50 includes a CPU, a ROM, a RAM, an A / D converter, an input / output interface, and the like. More specifically, the control unit 50 includes a plurality of ECUs (Electronic Control Units) such as ECT (Electronic Controlled Transmission) and EFI (Electronic Fuel Injection) (not shown). These ECUs communicate information by CAN (Controller Area Network). Specifically, the control unit 50 supplies data such as the rotational speed of the internal combustion engine 1 detected by the rotational speed sensor 21, the shift position detected by the shift position sensor 22, and on / off information of the air conditioner switch 23. Is done. The control unit 50 controls the opening degree of the throttle valve 4, the fuel injection amount from the fuel injection valve 5, the control of the ignition timing by the spark plug 10 and the like based on the supplied data. Execute. The control unit 50 also performs control such that an operation for turning off the air conditioner is prohibited. Note that each of the above-described sensors is an example, and actually, the control unit 50 is supplied with corresponding information from a large number of sensors. Further, the control target controlled by the control unit 50 is not limited to the above.

  In the present embodiment, the control unit 50 stores the data supplied from the above-described sensors and the like, and estimates the cause of the abnormality based on the stored data when an abnormality occurs in the vehicle 100. . Specifically, for each of the plurality of sensors, the control unit 50 calculates time difference data indicating the difference between the currently acquired data and the data acquired a predetermined time before each time difference data is calculated. The stored time difference data is updated with new time difference data. Further, the control unit 50 stops updating the time difference data when an abnormality occurs, and at this time, estimates the cause of the abnormality based on the time difference data corresponding to a plurality of sensors. Thereby, according to this embodiment, it is possible to reduce the storage amount of data used for estimating the cause of abnormality while appropriately estimating the cause of abnormality. The abnormality occurring in the vehicle 100 means a state such as an engine stall (engine stop) that has occurred in the vehicle 100 due to a change in driving conditions.

  Furthermore, the control unit 50 reflects in the control so that the abnormality does not occur in the vehicle 100 in the future based on the cause of the abnormality estimated as described above. In other words, the control unit 50 determines a measure for preventing the occurrence of an abnormality when an abnormality can occur in the future. Then, the control unit 50 executes the determined measure when a state in which such an abnormality can occur occurs. Thereby, according to this embodiment, it becomes possible to suppress the recurrence of abnormality appropriately.

  Thus, the control unit 50 functions as a vehicle abnormality diagnosis device in the present invention. Specifically, the control unit 50 operates as a time difference data calculation unit, a storage unit, an update unit, an abnormality determination unit, an abnormality cause estimation unit, and a control reflection unit.

[End diagnosis / prevention processing]
Next, as an example of processing performed by the control unit 50 described above, processing for performing diagnosis and prevention of engine stall (hereinafter referred to as “engine diagnosis / prevention processing”) will be described. In this process, the control unit 50 determines whether or not an engine stall has occurred. When it is determined that an engine stall has occurred, the cause of the engine stall is determined based on the stored time difference data. Is estimated. Then, the control unit 50 reflects in the control so that the engine stall does not occur again in the vehicle 100 based on the estimated cause of engine stall.

  FIG. 2 is a flowchart showing the engine stall diagnosis / prevention process. This process is repeatedly executed by the control unit 50 at a predetermined cycle.

First, in step S101, the control unit 50 calculates, for each of the plurality of sensors, time difference data indicating the difference between the currently acquired data and the data acquired before a predetermined time, and stores the time difference data stored therein. Is updated with the calculated new time difference data. Specifically, the currently acquired data is expressed as “X _i (t)”, the data acquired before the predetermined time T0 is expressed as “X _i (t−T0)”, and the time difference data is expressed as “X _i (t−T0)”. When expressed as “ΔX _i (t)”, the time difference data is expressed as “ΔX _i (t) = X _i (t) −X _i (t−T0)” (“i” indicates the index of each sensor. Show). When the time difference data is updated every time T1, time difference data ΔX _i (t−T1) is stored before the update. Therefore, the control unit 50 updates the stored time difference data ΔX _i (t−T1) with the calculated time difference data ΔX _i (t). The data acquired by the control unit 50 includes control data. Further, the control unit 50 stores the time difference data ΔX _i (t) in a RAM or the like. When the process in step S101 is completed, the process proceeds to step S102.

In step S <b> 102, the control unit 50 determines whether engine stall has occurred based on the rotational speed of the internal combustion engine 1. Specifically, the control unit 50 acquires the rotation speed of the internal combustion engine 1 detected by the rotation speed sensor 21, and determines whether or not the acquired rotation speed of the internal combustion engine 1 is equal to or less than a predetermined value. It is determined whether an engine stall has occurred. If an engine stall has occurred (step S102; Yes), the process proceeds to step S103. On the other hand, when the engine stall has not occurred (step S102; No), the process returns to step S101. In this case, the control unit 50 calculates and updates the time difference data ΔX _i (t) again. That is, the control unit 50 repeatedly calculates and updates the time difference data ΔX _i (t) until it is determined that an engine stall has occurred.

In step S103, the control unit 50 stops updating the time difference data ΔX _i (t). This is because if the update of the time difference data ΔX _i (t) is not stopped, the time difference data ΔX _i (t) at the time of occurrence of the engine stall is rewritten and deleted. That is, the control unit 50 stops updating in order to hold the time difference data ΔX _i (t) at the time of occurrence of the engine stall. When the process of step S103 is completed, the process proceeds to step S104.

  In step S104, the control unit 50 estimates the cause of engine stall based on time difference data corresponding to a plurality of sensors. Specifically, the control unit 50 extracts an item that affects the occurrence of engine stall (“item” means a detection target of the sensor) based on time difference data obtained from a plurality of sensors. . Here, a specific example of a method for estimating the cause of engine stall is given. In one example, the control unit 50 normalizes the time difference data for each of a plurality of sensors, and extracts an item having a large value in the normalized data (that is, an item in which a change in data becomes large when an engine stall occurs). be able to. In this case, the control unit 50 extracts the item causing the engine stall by comparing the normalized data with the threshold value. In another example, the control unit 50 can also distribute time difference data obtained from a plurality of sensors, and extract an item causing the engine stall based on this distribution. Note that the control unit 50 can extract a plurality of items.

  For example, when the time difference data of the rotational speed of the internal combustion engine 1 is a large value (in this case, the rotational speed changes suddenly before and after the engine stall), the control unit 50 sets the rotational speed of the internal combustion engine 1 as an item. Extract as Further, the control unit 50 extracts the shift position as an item when the time change data indicating the change of the shift position becomes a large value (in this case, the shift position changes before and after the engine stall). Furthermore, when the time difference data indicating ON / OFF of the air conditioner is a large value, the control unit 50 (in this case, the air conditioner is turned off from on or off before and after the engine stall), Extract air conditioner on / off as an item. In the case of the above-described example, the control unit 50 estimates a sudden change in the rotational speed of the internal combustion engine 1, a change in the shift position, on / off of the air conditioner, and the like as causes of the engine stall. When the process in step S104 is completed, the process proceeds to step S105.

  In step S105, the control unit 50 reflects the control so that the engine stall does not occur again in the vehicle 100 based on the cause of the engine stall estimated in step S104. In other words, the control unit 50 determines a measure that prevents the occurrence of engine stall in a state where engine stall can occur in the future. Specifically, a plurality of measures are stored in the control unit 50 in association with the items, and the control unit 50 corresponds to the items extracted in step S104 from the stored measures. Select a measure. For example, if it is estimated in step S104 that an engine stall has occurred due to a sudden change in the rotational speed of the internal combustion engine 1 and a change in the shift position, the control unit 50 selects a measure for prohibiting the operation of the air conditioner from on to off. Then, the control unit 50 controls the air conditioner switch 23 so that the air conditioner switch 23 will not be switched from on to off when a sudden change in the rotational speed of the internal combustion engine 1 and a change in the shift position occur in the future. When the above process ends, the process exits the flow.

  As described above, according to the engine stall diagnosis / prevention process described above, it is possible to reduce the storage amount of data used for estimating the engine stall cause while appropriately estimating the engine engine stall cause. Further, when an engine stall occurs in the future, appropriate control according to the cause of the engine stall can be performed, so that the engine stall can be prevented from occurring again.

  In the above-described embodiment, the process for diagnosing the engine stall and preventing the engine stall has been described, but the present invention is not limited to this. The present invention can also be applied to an abnormality that occurs in the vehicle 100 other than the engine stall.

1 is a schematic diagram illustrating a configuration of a vehicle to which a vehicle abnormality diagnosis device according to an embodiment of the present invention is applied. It is a flowchart which shows an engine stall diagnosis / prevention process.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Internal combustion engine 3 Intake passage 4 Throttle valve 5 Fuel injection valve 6a Cylinder 9 Exhaust passage 21 Rotational speed sensor 22 Shift position sensor 23 Air-conditioner switch 50 Control unit 100 Vehicle

Claims (4)

A vehicle abnormality diagnosis device that acquires data from a plurality of sensors provided in a vehicle and diagnoses an abnormality that has occurred in the vehicle based on the data,
For each of the plurality of sensors, time difference data calculating means for calculating time difference data between data acquired at present and data acquired before a predetermined time;
Storage means for storing the time difference data;
An abnormality diagnosis for a vehicle, comprising: update means for updating the time difference data stored in the storage means with the calculated new time difference data each time the time difference data is calculated. apparatus. Abnormality determining means for determining whether an abnormality has occurred in the vehicle;
An abnormality cause estimating means for estimating the cause of the abnormality based on the time difference data stored in the storage means when the abnormality determining means determines that an abnormality has occurred;
2. The vehicle abnormality according to claim 1, further comprising: a control reflection unit that reflects the control so that the abnormality does not occur again based on the cause of the abnormality estimated by the abnormality cause estimation unit. Diagnostic device.   The vehicle abnormality diagnosis apparatus according to claim 2, wherein the update unit stops updating the time difference data when the abnormality determination unit determines that an abnormality has occurred. The abnormality determination means determines whether an engine stall has occurred,
The abnormality cause estimating means estimates the cause of the engine stall,
The control reflecting means, when the abnormality cause determining means estimates that the engine stall has occurred due to a sudden change in the rotational speed of the internal combustion engine and a change in the shift position, the sudden change in the rotational speed of the internal combustion engine and the shift position in the future. 4. The vehicle abnormality diagnosis device according to claim 2, wherein when the change occurs, the control is performed so that an operation for turning the air conditioner from on to off is prohibited. 5.

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