Fuel injection drive signal generator and engine control system simulator

Abstract

To allow diagnosis of failures without using an actual vehicle.SOLUTION: A fuel injection drive signal generator generates a signal that simulates a normal-time fuel injection drive signal and a signal that simulates an abnormal-time fuel injection drive signal. The abnormal-time fuel injection drive signal has smaller values than the normal-time fuel injection drive signal in times which are not injection times and has larger values than the normal-time fuel injection drive signal in injection times.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a device for simulating a fault in an automobile. [Background technology]

[0002] In the education of automobile mechanics, fault diagnosis training is conducted using automobiles in which fault conditions are reproduced. For example, Patent Document 1 discloses a device that reproduces malfunctions or failures of operating devices such as automobile injectors, ignition coils, fuel pumps, and exhaust gas recirculation valves, and sensors such as crank angle sensors, MAF sensors, accelerator opening sensors, and vehicle speed sensors. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2018-205193 Summary of the Invention [Problem to be solved by the invention]

[0004] However, when many people need to carry out fault diagnosis at the same time, for example, when a test on fault diagnosis is to be given to many examinees, it is difficult to use an actual automobile.

[0005] SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to make it possible to perform fault diagnosis without using an actual automobile. [Means for solving the problem]

[0006] In order to solve the above problem, the fuel injection drive signal generating device of the present invention is a fuel injection drive signal generating device that generates a signal simulating a fuel injection drive signal in a normal state and a signal simulating a fuel injection drive signal in an abnormal state, and the fuel injection drive signal in the abnormal state has a smaller value than the fuel injection drive signal in a normal state outside the injection time, or has a larger value than the fuel injection drive signal in a normal state during the injection time.

[0007] Furthermore, the crank angle sensor signal generating device of the present invention generates a 1-degree simulation signal that simulates a 1-degree signal in which a pulse is generated every time the crank angle rotates by 1 degree, a 180-degree simulation signal that simulates a 180-degree signal in which a pulse is generated every time the crank angle rotates by 180 degrees, a signal in which some of the pulses are missing from the 1-degree simulation signal, and a signal in which some of the pulses are missing from the 180-degree simulation signal.

[0008] Furthermore, the crank angle sensor signal generator of the present invention generates a 1-degree simulation signal that simulates a 1-degree signal in which a pulse is generated every time the crank angle rotates by 1 degree, and a 180-degree simulation signal that simulates a 180-degree signal in which a pulse is generated every time the crank angle rotates by 180 degrees, and has input means for receiving input from a user, and determines, based on the input from the input means, whether the 180-degree simulation signal should be generated in synchronization with the 1-degree simulation signal or whether the 180-degree simulation signal should be generated asynchronously with the 1-degree simulation signal.

[0009] Moreover, the O2 sensor signal generating device of the present invention generates a signal simulating a signal generated by an O2 sensor in a normal state, and a signal indicating a constant value.

[0010] The engine control system simulator of the present invention may further include the fuel injection drive signal generator and the crank angle sensor signal generator, wherein a signal generated by the fuel injection drive signal generator is synchronized with a signal generated by the crank angle sensor signal. The engine control system simulator may further include an ignition control signal generator that generates an ignition control signal, wherein a signal generated by the fuel injection drive signal generator, a signal generated by the crank angle sensor signal, and a signal generated by the ignition control signal generator are synchronized. The engine control system simulator may further include the O2 sensor signal generator, a water temperature sensor signal generator 150 that simulates a signal generated by a water temperature sensor, and an air flow meter signal generator that simulates a signal generated by an air flow meter. [Effects of the Invention]

[0011] The present invention makes it possible to perform fault diagnosis without using an actual automobile. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a diagram showing an engine control system simulator 100 according to an embodiment of the present invention. [Figure 2] FIG. 1 is a diagram illustrating an example of an engine control system. [Figure 3] FIG. 4 is a diagram showing an example of a fuel injection drive signal in a normal state. [Figure 4] 10 is a diagram illustrating how the signals generated by the fuel injection drive signal generator 110, the ignition control signal generator 120, and the crank angle sensor signal generator 130 are synchronized. [Figure 5] FIG. 10 is a diagram showing an example of a signal simulating a fuel injection drive signal in an abnormal state. [Figure 6] FIG. 10 is a diagram showing an example of a signal simulating a one-degree signal in which some pulses are missing. [Figure 7] FIG. 10 is a diagram showing an example of a signal simulating a 180-degree signal in which some pulses are missing. [Figure 8] FIG. 10 is a diagram illustrating synchronization between a 1-degree signal and a 180-degree signal. [Figure 9] 4 is a diagram showing an example of a signal generated by an O2 sensor signal generating device 140. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0013] <Engine Control System Simulator 100> Fig. 1 is a diagram showing an engine control system simulator 100 according to one embodiment of the present invention. Generally, in an engine control system that controls an engine, an engine ECU acquires measurements from sensors such as a crank angle sensor, an O2 sensor, a water temperature sensor, and an air flow meter, and controls a fuel injector and an ignition device based on the acquired measurements. For example, as shown in Fig. 2, the fuel injector, ignition device, O2 sensor, water temperature sensor, and air flow meter are connected to the engine ECU.

[0014] Therefore, the engine control system simulator 100 according to this embodiment includes a fuel injection drive signal generator 110, an ignition control signal generator 120, a crank angle sensor signal generator 130, an O2 sensor signal generator 140, a water temperature sensor signal generator 150, and an air flow meter signal generator 160.

[0015] <Fuel injection drive signal generator 110> The fuel injection drive signal generating device 110 generates a signal that simulates the fuel injection drive signal. The fuel injection control signal generating device 110 may be configured by hardware or software.

[0016] As shown in FIG. 2, the fuel injection device has a coil disposed between the engine ECU and a power supply. When current is passed through this coil, the coil attracts a plunger, thereby opening a valve and injecting fuel. The fuel injection drive signal is obtained, for example, by measuring the voltage between terminal F1 (F2, F3, F4) in FIG. 2 and the body ground. Under normal conditions, as shown in FIG. 3, for example, the voltage becomes zero during the injection time, a surge voltage occurs at the end of the injection time, and then returns to the power supply voltage. The fuel injection drive signal generator 110 generates a signal simulating such a fuel injection drive signal under normal conditions. Furthermore, as shown in FIG. 4, for example, the fuel injection drive signal generator 110 generates a signal simulating a fuel injection drive signal for each cylinder of a four-cylinder engine.

[0017] When the fuel injection drive signal generating device 110 is configured as hardware, it is preferable to provide a coil with the same capacity as the coil used in the fuel injection device, and to generate a signal simulating the fuel injection drive signal under normal conditions by turning this coil on and off.

[0018] Furthermore, the fuel injection drive signal generating device 110 is preferably configured to generate an abnormal signal that simulates a fuel injection drive signal in an abnormal state, in addition to a signal that simulates a fuel injection drive signal in a normal state. The fuel injection drive signal generating device 110 is preferably configured to generate an abnormal signal as shown in FIG. 5. In this way, it becomes possible to simulate a fuel injection drive signal in an abnormal state that occurs when the fuel control device fails. In other words, in this way, it becomes possible to simulate a failed state of the fuel control device.

[0019] FIG. 5(A) simulates a signal that is output when the resistance on the downstream side of the coil (engine ECU side) increases. In the abnormal signal (solid line) shown in FIG. 5(A), the voltage value during the injection time is no longer zero, and the shape of the signal during the injection time differs from that of the normal signal (dashed line). FIG. 5(B) simulates a signal that is output when the resistance on the upstream side of the coil (power supply side) increases. In the abnormal signal (solid line) shown in FIG. 5(B), the voltage value decreases outside the injection time, and the shape of the signal during the injection time differs from that of the normal signal (dashed line). In this way, the fuel injection drive signal generating device 110 may be configured to generate an abnormal signal when the resistance value on the downstream side of the coil increases, and an abnormal signal when the resistance value on the upstream side of the coil increases, for example.

[0020] The fuel injection drive signal generating device 110 may have a means for receiving input from a user, such as a test organizer who conducts a test related to fault diagnosis or an instructor who provides training related to fault diagnosis, and may determine, based on the input from the user, whether to generate a signal simulating a fuel injection drive signal under normal conditions, an abnormal signal when the resistance value on the upstream side of the coil increases, or an abnormal signal when the resistance value on the downstream side of the coil increases.Furthermore, the fuel injection drive signal generating device 110 may determine the resistance values ​​of the resistors on the upstream side of the coil and the resistors on the downstream side of the coil based on the input from a user, such as a test organizer who conducts a test related to fault diagnosis or an instructor who provides training related to fault diagnosis.

[0021] The fuel injection drive signal generating device 110 may be configured as a combination of a device that generates a signal simulating a normal fuel injection drive signal and a device that generates an abnormal signal by modifying the signal output from this device.

[0022] The engine control system simulator 100 preferably has an engine speed input means for receiving input of the engine speed from a user such as a test organizer who conducts a test related to fault diagnosis or an instructor who conducts training related to fault diagnosis, and the fuel injection drive signal generator 110 preferably generates a signal simulating the fuel injection drive signal having a period corresponding to the input speed. For example, the input means may be capable of receiving speeds such as 650 rpm or 2000 rpm from the user.

[0023] <Ignition control signal generator 120> The ignition control signal generator 120 generates a signal simulating an ignition control signal. The ignition control signal is obtained, for example, by measuring the voltage between terminal S1 (S2, S3, S4) in FIG. 2 and the body ground. The ignition control signal generator 120 generates a signal simulating an ignition control signal for each cylinder of a four-cylinder engine, for example, as shown in FIG. 4. In this case, the ignition control signal generator 120 may generate a signal simulating an ignition control signal having a period corresponding to the engine speed input by the engine speed input means of the engine control system simulator 100. Furthermore, the signal generated by the ignition control signal generator 120 may be synchronized with the signal generated by the fuel injection drive signal generator 120, for example, as shown in FIG. 4. In FIG. 4, the ignition order is cylinder 1, cylinder 3, cylinder 4, and cylinder 2. For example, when cylinder 1 is ignited, fuel is injected into cylinder 4.

[0024] <Crank Angle Sensor Signal Generator 130> The crank angle sensor signal generator 130 generates a signal simulating a signal generated by the crank angle sensor. The signals generated by the crank angle sensor include a 1-degree signal, which generates a pulse every time the crank angle rotates by one degree, and a 180-degree signal, which generates a pulse every time the crank angle rotates by 180 degrees. The crank angle sensor signal generator 130 generates a 1-degree simulation signal that simulates the 1-degree signal and a 180-degree simulation signal that simulates the 180-degree signal. In this case, it is preferable that the crank angle sensor signal generator 130 generates the 1-degree simulation signal and the 180-degree simulation signal with a period that corresponds to the rotation speed input by the engine rotation speed input means of the engine control system simulator 100.

[0025] In addition to the 1-degree simulation signal, the crank angle sensor signal generating device 130 may be configured to generate an abnormal signal in which some pulses are missing from the 1-degree simulation signal, as shown in FIG. 6. This makes it possible to simulate a 1-degree signal in which some pulses are missing due to a crank angle sensor failure. In other words, this makes it possible to simulate a crank angle sensor failure. In this case, the crank angle sensor signal generating device 130 may be configured as a combination of a device that generates a 1-degree simulation signal and a device that generates an abnormal signal in which some pulses are missing by modifying the 1-degree simulation signal output from this device.

[0026] The crank angle sensor signal generating device 130 may have a means for receiving input from a user, such as a test organizer who organizes a test related to fault diagnosis or an instructor who provides training related to fault diagnosis, and may determine, based on the input from the user, whether to generate a single simulation signal or an abnormal signal in which some pulses are missing.

[0027] In addition to the 180-degree simulation signal, the crank angle sensor signal generator 130 may be configured to generate an abnormal signal in which some pulses are missing from the 180-degree simulation signal, as shown in FIG. 7. This makes it possible to simulate a 180-degree signal in which some pulses are missing due to a crank angle sensor failure. In other words, this makes it possible to simulate a crank angle sensor failure state. In this case, the crank angle sensor signal generator 130 may be configured as a combination of a device that generates the 180-degree simulation signal and a device that generates an abnormal signal in which some pulses are missing by modifying the signal output from this device.

[0028] The crank angle sensor signal generating device 130 may determine whether to generate a 180-degree simulation signal or an abnormal signal with some pulses missing, based on input from a user such as a test organizer who organizes a test related to fault diagnosis or an instructor who provides training related to fault diagnosis.

[0029] If the crank angle sensor is normal, the 180-degree signal and the 1-degree signal will be synchronized, as shown in Figure 8(A). In other words, the rising time of the pulse of the 180-degree signal will match the rising time of the pulse of the 1-degree signal. Therefore, it is recommended that the crank angle sensor signal generator 130 generate the 1-degree simulation signal and the 180-degree simulation signal so that they are synchronized, as shown in Figure 8(A).

[0030] Furthermore, the crank angle sensor signal generating device 130 may be configured to generate the 1-degree and 180-degree simulation signals asynchronously, in addition to generating the 1-degree and 180-degree simulation signals synchronously, as shown in FIG. 8B. In FIG. 8B, the rising edge of the 180-degree signal pulse is shifted from the rising edge of the 1-degree signal pulse. This configuration simulates a crank angle sensor malfunction in which the 1-degree and 180-degree signals are asynchronous. In other words, this configuration simulates a crank angle sensor malfunction. In this case, the crank angle sensor signal generating device 130 may be configured as a combination of a device that generates the 1-degree and 180-degree simulation signals synchronously and a device that generates the 1-degree and 180-degree simulation signals asynchronously by modifying the signal output from the device that generates the 1-degree and 180-degree simulation signals asynchronously.

[0031] The crank angle sensor signal generating device 130 may determine whether to generate the 1-degree simulation signal and the 180-degree simulation signal in a synchronized manner or asynchronously, based on input from a user such as a test organizer who organizes a test related to fault diagnosis or an instructor who provides training related to fault diagnosis.

[0032] Furthermore, the signal generated by the crank angle sensor signal generator 130 may be synchronized with the signal generated by the fuel injection drive signal generator 120 and the signal generated by the ignition control signal generator 120, as shown in Fig. 4. In Fig. 4, every time the crank angle rotates 180 degrees, ignition occurs in one of the cylinders and fuel injection occurs in one of the cylinders.

[0033] Incidentally, in the above description, the crank angle sensor signal generator 130 generates a signal simulating the signal generated by the crank angle sensor for a 4-cylinder engine. However, for example, when the crank angle sensor signal generator 130 generates a signal simulating the signal generated by the crank angle sensor for a 6-cylinder engine, the crank angle sensor signal generator 130 generates a signal simulating a 120-degree signal in which a pulse is generated every time the crank angle rotates 120 degrees, instead of the 180-degree simulation signal.

[0034] <O2 sensor signal generator 140> The O2 sensor signal generator 140 generates a signal simulating the signal generated by the O2 sensor. The signal generated by the O2 sensor can be obtained, for example, by measuring the voltage between the terminal O and the body ground in FIG. 2. When the O2 sensor is normal, it generates a signal that vibrates like a sine wave as shown in FIG. 9. Therefore, the O2 sensor signal generator 140 generates a signal simulating this vibrating signal as the signal simulating the signal generated by the normal O2 sensor.

[0035] In addition to the signal simulating the signal generated by the normal O2 sensor, the O2 sensor signal generator 140 may be made to generate an abnormal signal indicating a certain voltage value. For example, the O2 sensor signal generator 140 may generate a 0V signal that always indicates 0V or a 1V signal that always indicates 1V. By doing so, it becomes possible to simulate the state where the O2 sensor fails and does not generate a vibrating signal. That is, by doing so, it becomes possible to simulate the failure state of the O2 sensor.

[0036] The O2 sensor signal generator 140 may be provided with means for receiving an input from a user such as a test organizer who holds a test related to fault diagnosis or an instructor who conducts training related to fault diagnosis, and based on this input from the user, determines whether to generate a signal simulating the signal generated by the normal O2 sensor, a 0V signal, or a 1V signal.

[0037] In addition, the O2 sensor signal generating device 140 may record a signal generated by an actual O2 sensor and reproduce this recorded signal to generate a signal that simulates the signal generated by an O2 sensor under normal conditions.

[0038] <Water temperature sensor signal generator 150> The water temperature sensor signal generator 150 generates a signal simulating the signal generated by the water temperature sensor. The signal generated by the water temperature sensor can be obtained, for example, by measuring the voltage between terminal W in FIG. 2 and the body earth. When the water temperature sensor is normal, it generates a signal indicating a constant voltage value corresponding to the water temperature. Therefore, the water temperature sensor signal generator 150 generates a signal indicating a voltage value between 0V and 5V. The water temperature sensor signal generator 150 should preferably have a means for receiving input from a user, such as a test organizer who conducts tests related to fault diagnosis or an instructor who provides training related to fault diagnosis, and the voltage value of the signal to be generated should be determined based on this input from the user.

[0039] <Air flow meter signal generator 160> Air flow meter signal generator 160 generates a signal simulating the signal generated by the air flow meter. The signal generated by the air flow meter can be obtained, for example, by measuring the voltage between terminal A in FIG. 2 and the body earth. When the air flow meter is normal, it generates a signal indicating a constant voltage value corresponding to the air volume. Therefore, air flow meter signal generator 160 generates a signal indicating a voltage value between 0V and 5V. Air flow meter signal generator 160 should preferably have a means for receiving input from a user, such as a test organizer who conducts tests related to fault diagnosis or an instructor who provides training related to fault diagnosis, and the voltage value of the signal to be generated should be determined based on this user input.

[0040] The signals generated by actual aerometers contain noise. Therefore, it is preferable that the air flow meter signal generating unit 160 generates a signal that contains noise. In this case, the air flow meter signal generating unit 160 may be configured as a combination of a device that generates a noise-free signal and a device that generates a signal by adding noise to the signal output from this device.

[0041] <Measurement terminal> Each of the fuel injection drive signal generator 110, the ignition control signal generator 120, the crank angle sensor signal generator 130, the O2 sensor signal generator 140, the water temperature sensor signal generator 150, and the air flow meter signal generator 160 may have a measurement terminal that allows a person undergoing testing or training to measure the generated signals. This configuration makes it possible to test or train the engine control system without using an actual vehicle. For example, the person undergoing testing or training may apply a voltmeter to the measurement terminals of each device on the engine control system simulator 100 and to a reference potential measurement terminal, and measure the voltage between the measurement terminals. Alternatively, the engine control system simulator 100 may further include checkboxes with measurement terminals, so that the signals generated by the fuel injection drive signal generator 110, the ignition control signal generator 120, the crank angle sensor signal generator 130, the O2 sensor signal generator 140, the water temperature sensor signal generator 150, and the air flow meter signal generator 160 can be measured via the measurement terminals of the checkboxes.

[0042] The present invention has been described above in terms of preferred embodiments thereof. While the present invention has been described herein with reference to specific examples, various modifications and variations can be made to these examples without departing from the spirit and scope of the present invention as set forth in the claims. [Explanation of symbols]

[0043] 100 Engine Control System Simulator 110 Fuel injection drive signal generator 120 Ignition control signal generator 130 Crank angle sensor signal generator 140 O2 sensor signal generator 150 Water temperature sensor signal generator 160 Air flow meter signal generator

Claims

1. A fuel injection drive signal generating device for use in an automobile engine control system simulator, which generates a signal simulating a fuel injection drive signal in a normal state and a signal simulating a fuel injection drive signal in an abnormal state, the signal simulating the fuel injection drive signal is a signal simulating a voltage signal of a coil terminal of a fuel injection device, the abnormal fuel injection drive signal has a smaller value than the normal fuel injection drive signal at times other than the injection time, or has a larger value than the normal fuel injection drive signal at the injection time, The fuel injection drive signal generating device includes: a first device for generating a signal simulating the fuel injection drive signal in a normal state; a second device that generates a signal simulating the fuel injection drive signal at the time of the abnormality by modifying the signal output from the first device.

2. a fuel injection drive signal generating device according to claim 1; a crank angle sensor signal generating device for generating a signal simulating a crank angle sensor signal, an engine control system simulator, wherein the signal generated by the fuel injection drive signal generating device and the signal generated by the crank angle sensor signal generating device are synchronized;

3. The crank angle sensor signal generating device includes: a one-degree simulated signal that simulates a one-degree signal in which a pulse is generated every one degree of crank angle rotation; a 180-degree simulated signal that simulates a 180-degree signal in which a pulse is generated every time the crank angle rotates 180 degrees; a signal in which some pulses are missing from the one-degree simulation signal; 3. The engine control system simulator according to claim 2, wherein the 180-degree simulation signal is generated by subtracting some pulses from the 180-degree simulation signal.

4. The crank angle sensor signal generating device includes: generating a 1-degree simulation signal that simulates a 1-degree signal in which a pulse is generated every time the crank angle rotates by 1 degree, and a 180-degree simulation signal that simulates a 180-degree signal in which a pulse is generated every time the crank angle rotates by 180 degrees; having an input means for receiving an input from a user; 3. The engine control system simulator according to claim 2, wherein it is determined whether the 180-degree simulation signal is generated in synchronization with the 1-degree simulation signal or whether the 180-degree simulation signal is generated asynchronously with the 1-degree simulation signal based on an input from the input means.

5. further comprising an ignition control signal generator for generating an ignition control signal; 5. The engine control system simulator according to claim 2, wherein the signal generated by the fuel injection drive signal generating device, the signal generated by the crank angle sensor signal generating device, and the signal generated by the ignition control signal generating device are synchronized.

6. An O2 sensor signal generator that generates a signal simulating a signal generated by an O2 sensor under normal conditions and a signal indicating a constant value; a water temperature sensor signal generator that simulates a signal generated by the water temperature sensor; and an air flow meter signal generator that simulates a signal generated by the air flow meter, 6. The engine control system simulator according to claim 2, wherein the O2 sensor signal generator records a signal generated by an actual O2 sensor and reproduces the recorded signal to generate a signal simulating a signal generated by the O2 sensor in a normal state.

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