Electronic control device

Abstract

To provide an electronic control device capable of indicating whether a failure location is in a controlled unit or in a control unit.SOLUTION: An electronic control device being a control unit for controlling a controlled unit, comprises: a failure detection unit that detects a failure of the controlled unit and the control unit and outputs failure detection information according to a failure phenomenon; and a failure location evaluation unit that stores a plurality of failure locations in correspondence with the failure detection information and evaluates whether the failure location is in the controlled unit or in the control unit on the basis of the failure detection information input from the failure detection unit.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an electronic control device. [Background technology]

[0002] The following Patent Document 1 discloses an electrical load abnormality detection device and an electronic control device that are intended to distinguish between an open circuit fault in an electrical load and a ground short circuit when a drive switching means is turned off in a low-side drive type electronic control device.

[0003] In this abnormality detection device and electronic control device, an ECU equipped with an N-channel MOSFET that energizes and drives a load on the low side has resistors provided between the power supply voltage and an output terminal (the drain of the N-channel MOSFET) and between the output terminal and ground, and the resistance value of each resistor is set so that the voltage at the output terminal when the N-channel MOSFET is off becomes half the power supply voltage in the event of a wire break in the load, and becomes approximately the power supply voltage under normal conditions.A comparator compares a pair of determination voltages with the above voltage to determine whether a wire break has occurred or whether a ground short has occurred, and performs different fail-safe processing for each detected fault. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2004-347423 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the above-mentioned background art, the voltage at a specific point in the drive circuit is measured, and open circuit faults and ground shorts (short circuit faults) are detected based on a comparison between the voltage at the output terminal and a pair of preset judgment voltages, and there is a problem in that it is not possible to determine whether the cause of the fault lies in the electrical load (the controlled unit) or in the electronic control device (control unit) that controls and drives the electrical load (the controlled unit).

[0006] The present invention has been made in view of the above-mentioned circumstances, and has as its object to provide an electronic control device that can indicate whether the faulty part is in a controlled part or in a control part. [Means for solving the problem]

[0007] In order to achieve the above object, the present invention adopts, as a first solution means relating to an electronic control device, a means in which the electronic control device is a control unit that controls a controlled unit, and is equipped with a fault detection unit that detects faults in the controlled unit and the control unit and outputs fault detection information according to the fault phenomenon, and a fault location evaluation unit that stores multiple fault locations corresponding to the fault detection information and evaluates whether the fault location is in the controlled unit or the control unit based on the fault detection information input from the fault detection unit.

[0008] In the present invention, as a second solution related to an electronic control device, in the above-mentioned first solution, the fault location evaluation unit employs a means in which an error flag indicating whether the fault location is in the controlled unit or the control unit is pre-registered in correspondence with the fault detection information, and outputs the error flag corresponding to the fault detection information input from the fault detection unit.

[0009] In the present invention, as a third solution related to an electronic control device, in the above-mentioned first or second solution, the fault location evaluation unit stores, in addition to the fault location, a fault factor corresponding to the fault detection information, and outputs the fault factor corresponding to the fault detection information input from the fault detection unit.

[0010] The present invention employs, as a fourth solution relating to an electronic control device, a solution in which, in any one of the first to third solution means, the controlled unit is an injector of an engine. [Effects of the Invention]

[0011] According to the present invention, it is possible to provide an electronic control device that can indicate whether the fault is in the controlled unit or the control unit. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a block diagram showing a configuration of an injector control device according to an embodiment of the present invention; [Figure 2] FIG. 2 is a schematic diagram showing the data structure of a failure location evaluation table according to an embodiment of the present invention. [Figure 3] 4 is a flowchart illustrating a failure detection operation in one embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0013] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. 1, the injector control device A according to this embodiment includes a CPU (Central Processing Unit) 1, an injector control IC (Integrated Circuit) 2, and a driver circuit 3. The injector control device A is a control unit that controls an injector 4 provided in a vehicle system F (engine).

[0014] That is, this injector control device A is provided incidentally in various vehicles equipped with various engines (internal combustion engines) such as gasoline engines and diesel engines, and is a control unit that controls and drives the injector 4 (controlled unit) by outputting a predetermined drive signal to the injector 4. Such an injector control device A corresponds to the electronic control device according to the present invention.

[0015] To explain each component, namely, the CPU 1, the injector control IC 2, the driver circuit 3, and the injector 4 in detail, the CPU 1 is electrically connected to the injector control IC 2 so as to be able to freely send and receive signals, and by executing a pre-stored injector control program, generates various signals necessary to control the injector 4 (the controlled unit) and outputs them to the injector control IC 2.

[0016] That is, the CPU 1 includes a ROM (Read Only Memory) and a RAM (Random Access Memory), and an injector control program is stored in the ROM. The CPU 1 reads the injector control program from the ROM and executes the injector control program.

[0017] The injector control program in this embodiment has a fault detection and evaluation function in addition to its main function of controlling the injector 4. The fault detection function will be described in detail later, but this fault detection and evaluation function is a function that evaluates whether the fault is in the injector 4 (controlled portion) or the injector control device A (control portion) based on a fault detection code (fault detection information) obtained from the injector control IC 2.

[0018] That is, the CPU 1 in this embodiment functions as a control unit that controls the (controlled unit) of the injector 4, and also functions as a fault location evaluation unit that evaluates whether the fault location is in the injector 4 (controlled unit) or the injector control device A (control unit). Such a CPU 1 corresponds to the fault location evaluation unit of the present invention.

[0019] The CPU 1 stores a predetermined data table (fault location evaluation table) in the ROM to function as a fault location evaluation unit. This fault location evaluation table is a data table corresponding to the fault detection code input from the injector control IC 2, and has a data structure such as that shown in Figure 2.

[0020] That is, the failure location evaluation table includes at least a failure detection code, a failure location, an error flag, and a failure cause as table elements, as shown in Fig. 2. The failure detection code is failure detection information input from the injector control IC 2, and is a code of a predetermined data length corresponding to the failure phenomenon.

[0021] The fault location is the faulty part in the controlled unit and the control unit corresponding to the fault detection code. The error flag is a 1-bit code that indicates whether the fault location corresponds to the control unit or the controlled unit. That is, in the error flag, the code "1" indicates that it corresponds to the fault location, and the code "0" indicates that it does not correspond to the fault location.

[0022] 2, for example, for the error flag corresponding to the fault detection code "C01," "1" is set in the control unit, and "0" is set in the controlled unit. Therefore, this fault location evaluation table indicates that the fault location corresponding to the fault detection code "C01" corresponds to the control unit.

[0023] 2, the failure factor is a code of a predetermined data length indicating the cause of the failure. Such a failure location evaluation table is a table (data table) in which error flags indicating whether the failure location is in the injector 4 (controlled portion) or the injector control IC 2 (control portion) are registered in advance in correspondence with failure detection codes (failure detection information).

[0024] Although not shown in Figure 1, the CPU 1 has a function for sending and receiving signals to external devices. In response to an information request received from an external device, the CPU 1 outputs to the external device the control operation status of itself as a control unit and the injector control IC 2, as well as the evaluation results as a fault location evaluation unit.

[0025] The injector control IC 2 is electrically connected to the CPU 1 and also to the driver circuit 3. The injector control IC 2 generates control commands based on various signals input from the CPU 1 and outputs them to the driver circuit 3. The control commands are generated signals that instruct the driver circuit 3 on the valve opening and closing timings of the injector 4.

[0026] That is, the injector control IC 2 is an IC (Integrated Circuit) dedicated to injector control, which controls the valve opening and closing timings of the injector 4 via the driver circuit 3. The injector control IC 2, together with the above-mentioned CPU 1, constitutes the control unit of the present invention.

[0027] In addition to functioning as a control unit, the injector control IC 2 has the function of detecting failures in itself, which constitutes the control unit, and in the injector 4 (controlled unit) directly connected to it. That is, the injector control IC 2 detects failures in itself (control unit) and the injector 4 (controlled unit) by monitoring the voltages of monitoring points pre-installed in each part of itself, and outputs a failure detection code corresponding to the failure phenomenon to the CPU 1 (failure location evaluation unit). Such an injector control IC 2 corresponds to the failure detection unit of the present invention. Furthermore, the failure detection code corresponds to the failure detection information of the present invention.

[0028] As shown in the figure, the driver circuit 3 is electrically connected to the injector control IC 2 and also electrically connected to the injector 4. The driver circuit 3 generates a drive signal based on a control command (control signal) input from the injector control IC 2 and outputs the drive signal to the injector 4.

[0029] The driver circuit 3 is, for example, a switching circuit including a switching transistor. That is, the driver circuit 3 sets the switching transistor to an ON state (conducting state) or an OFF state (non-conducting state) based on a control command (control signal) input from the injector control IC 2, thereby passing a drive current through the injector 4 during the ON period (conducting period) of the switching transistor. The driver circuit 3, together with the CPU 1 and the injector control IC 2, constitutes a control unit.

[0030] The injector 4 is an injection valve (solenoid valve) electrically connected to the above-mentioned driver circuit 3. The injector 4 is a controlled object (a controlled unit) of a control unit (injector control device A) that is made up of the CPU 1, the injector control IC 2, and the driver circuit 3. In other words, the injector 4 is a load (a controlled load) of the control unit (injector control device A).

[0031] The injector 4 opens or closes based on a drive signal (drive current) input from the driver circuit 3. The base state of the injector 4 is a closed state, and the injector 4 opens when a drive current is applied from the driver circuit 3 and closes when the drive current is cut off. In other words, the injector 4 injects an amount of fuel into the engine cylinder according to the open valve period.

[0032] Various types of engines (internal combustion engines) are widely known, and vehicle engines include not only single-cylinder engines but also multi-cylinder engines. Therefore, in the case of a multi-cylinder engine, a plurality of injectors 4 (controlled units) are provided according to the number of cylinders. In this case, the injector control device functioning as a control unit controls the plurality of injectors 4 (controlled units) in parallel.

[0033] The injector control device A according to this embodiment is a control unit that controls the injector 4 (the controlled unit) by electrically interconnecting the CPU 1, the injector control IC 2, the driver circuit 3, and the injector 4 (the controlled unit). In other words, the injector control device A is an assembly of multiple circuit components that constitute the CPU 1, the injector control IC 2, and the driver circuit 3.

[0034] For example, the driver circuit 3 and the injector 4 (controlled unit) are mounted near the engine with a physical distance between them, and are therefore electrically connected using a predetermined harness (connecting wire). That is, a harness (connecting wire) is interposed between the driver circuit 3 and the injector 4 as a separate component.

[0035] If a wire breakage or ground fault occurs in such a harness (connecting wire), the injector control device A will be unable to properly control the injector 4 (controlled portion). Therefore, in order to ensure soundness in the control of the injector 4 (controlled portion) by the injector control device A, it is necessary to detect whether a wire breakage, ground fault, or other fault has occurred in a circuit component such as the harness (connecting wire).

[0036] Furthermore, in order to respond to a failure, the injector control device A needs to accurately and quickly determine whether the failure is in the injector 4 (controlled portion) or the injector control device A (control portion). The above-mentioned function of the injector control IC 2 as a failure detection unit and the function of the CPU 1 as a failure location evaluation unit are functions for ensuring the soundness of the control of the injector 4 (controlled portion) by the injector control device A.

[0037] Next, the operation of the main parts of the injector control device A (electronic control device) according to this embodiment, that is, the failure detection operation, will be described with reference to the flowchart shown in FIG.

[0038] Here, the main operation of the injector control device A, that is, the control operation of the injector 4 (controlled portion), will be explained first. When the injector control device A is started, the CPU 1 executes the injector control program to generate various signals necessary to control the injector 4 (controlled portion). Then, the CPU 1 outputs the various signals to the injector control IC 2.

[0039] The injector control IC 2 generates a control command (control signal) based on the various signals described above and outputs it to the driver circuit 3. Then, the driver circuit 3 generates a drive signal based on the control command (control signal) and outputs it to the injector 4. Then, the injector 4 opens and closes based on a drive current that is supplied based on the drive signal.

[0040] That is, the injector 4 (controlled unit) is controlled by the cooperation of the electrically interconnected CPU 1, injector control IC 2, and driver circuit 3, that is, the control operation of the injector control device A. As a result, an amount of fuel according to the control operation of the injector control device A is injected into the cylinder of the engine.

[0041] In the injector control device A, the injector control IC 2 functions as a failure detection unit to detect failures in itself (control unit) and the injector 4 (controlled unit) (step S1). Then, the injector control IC 2 outputs a failure detection code corresponding to the failure phenomenon detected by itself to the CPU 1 (failure location evaluation unit).

[0042] The CPU 1 functions as a fault location evaluation unit and acquires table information corresponding to the fault detection code by searching a fault location evaluation table based on the fault detection code acquired from the injector control IC 2 (step S2).Then, the CPU 1 identifies the fault location based on the table information (step S3) and outputs it to the outside.

[0043] Furthermore, the CPU 1 determines whether the fault is in the injector 4 (controlled portion) or the injector control IC 2 (control portion) based on the error flag also included in the table information (step S4), and outputs the determination result to the outside. If the determination in step S4 is "Yes," that is, the fault is in the injector control IC 2 (control portion), the CPU 1 identifies the cause of the fault in the injector control IC 2 based on the table information (step S5), and outputs the result to the outside.

[0044] Then, when the process of step S4 is completed, the CPU 1 ends the failure evaluation process as the failure location evaluation unit. Also, even if the determination of step S4 is "No", that is, if the failure location is the injector 4 (the controlled unit), the CPU 1 ends the failure evaluation process as the failure location evaluation unit.

[0045] The injector control device A (electronic control device) according to this embodiment is a control unit that controls the injector 4 (controlled unit), and includes an injector control IC2 (failure detection unit) that detects failures in the injector 4 (controlled unit) and the injector control IC2 (control unit) and outputs a failure detection code (failure detection information) corresponding to the failure phenomenon, and a CPU1 (failure location evaluation unit) that stores a plurality of failure locations in a table (failure location evaluation table) corresponding to the failure detection codes (failure detection information) and evaluates whether the failure location is in the injector 4 (controlled unit) or the injector control IC2 (control unit) based on the failure detection code (failure detection information) input from the injector control IC2 (failure detection unit).

[0046] According to this embodiment, since the electronic control device A is equipped with an injector control IC 2 (fault detection unit) and a CPU 1 (fault location evaluation unit), it is possible to provide an electronic control device A that can indicate whether the fault location is in the injector 4 (controlled unit) or the injector control IC 2 (control unit).

[0047] In the above embodiment, the present invention (electronic control device) is applied to the injector control device A, but the present invention is not limited to this. That is, the present invention (electronic control device) is not limited to the injector control device A, and therefore the controlled part of the present invention is not limited to the injector 4 of the engine. [Explanation of symbols]

[0048] A Injector control device (control unit, electronic control device) F vehicle system 1 CPU(Central Processing Unit) 2. Injector Control IC (Integrated Circuit) 3 Driver circuit 4 Injector (controlled part)

Claims

1. An electronic control device that is a control unit that controls a controlled unit, a failure detection unit that detects a failure in the controlled unit and the control unit and outputs failure detection information according to the failure phenomenon; a failure location evaluation unit that stores a plurality of failure locations corresponding to the failure detection information and evaluates whether the failure location is in the controlled unit or the control unit based on the failure detection information input from the failure detection unit; An electronic control device comprising:

2. The electronic control device according to claim 1, characterized in that the fault location evaluation unit includes a table in which error flags indicating whether the fault location is in the controlled part or the control part are registered in advance in correspondence with the fault detection information, and outputs the error flag corresponding to the fault detection information input from the fault detection unit.

3. 3. The electronic control device according to claim 1, wherein the failure location evaluation unit stores a failure factor corresponding to the failure detection information in addition to the failure location, and outputs the failure factor corresponding to the failure detection information input from the failure detection unit.

4. 3. The electronic control device according to claim 1, wherein the controlled unit is an injector of an engine.

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