Electronic control unit

Abstract

To provide an electronic control device which can identify a clogging of a respiration filter at an early stage.SOLUTION: An electronic control device 10 includes: a housing 20; a respiration filter 40 provided at the housing 20 and having an air permeability and water resistance; an air pressure sensor 51 detecting an air pressure inside the housing 20; and a control part 322 for controlling drive of a load 90. When a pressure difference between a first pressure detected by the air pressure sensor 51 at start-up and a second pressure detected by the air pressure sensor 51 after a lapse of predefined time exceeds a preset value after the start-up, the control part 322 determines an error of the respiration filter 40.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present disclosure relates to electronic control devices. [Background technology]

[0002] Conventionally, there has been known an electronic control device mounted on, for example, a vehicle, etc. In the electronic control device, a printed circuit board on which electronic components are mounted is housed in a waterproof case, i.e., a housing, and the housing is provided with a breathing filter for allowing ventilation between the inside and outside of the housing. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2007-141959 Summary of the Invention [Problem to be solved by the invention]

[0004] For example, when the engine starts, the electronic components inside the housing generate heat, causing the temperature inside the housing to rise. If the breathing filter becomes clogged, breathing between the inside and outside of the housing will no longer function, causing the pressure inside the housing to temporarily rise, resulting in a pressure difference between the inside and outside of the housing. In this case, since load control is performed based on the pressure inside the housing, there is a risk of problems such as inappropriate control. However, in conventional configurations, clogged breathing filters have been detected by visual inspection, making it difficult to identify clogged breathing filters early.

[0005] The present disclosure has been made in consideration of the above circumstances, and an object of the present disclosure is to provide an electronic control device that can identify clogging of a breathing filter at an early stage. [Means for solving the problem]

[0006] In order to achieve the above object, one embodiment of the electronic control device comprises a housing (20), a breathable and waterproof breathing filter (40) provided in the housing, an atmospheric pressure sensor (51) that detects the atmospheric pressure inside the housing, and a control unit (322) that controls the driving of a load (90), and the control unit determines an abnormality in the breathing filter when the pressure difference between a first pressure detected by the atmospheric pressure sensor at startup and a second pressure detected by the atmospheric pressure sensor after a predetermined time has elapsed since startup exceeds a set value. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a cross-sectional view schematically illustrating an example of the configuration of an electronic control device according to a first embodiment. [Figure 2] FIG. 1 is a block diagram showing an example of an electrical configuration of an electronic control device according to a first embodiment; [Figure 3] FIG. 10 is a diagram showing an example of a change in air pressure inside the housing over time when a breathing filter becomes clogged in the electronic control device according to the first embodiment. [Figure 4] 10 is a flowchart showing an example of control executed by the control unit when determining whether the breathing filter is clogged in the electronic control device according to the first embodiment. [Figure 5] 10 is a flowchart showing an example of control executed by a control unit when determining whether a breathing filter is clogged in the electronic control device according to the second embodiment. [Figure 6] 10 is a flowchart showing an example of control executed by the control unit when determining whether the breathing filter is clogged in the electronic control device according to the third embodiment. [Figure 7] FIG. 10 is a cross-sectional view schematically illustrating an example of the configuration of an electronic control device according to a fourth embodiment. [Figure 8] 10 is a flowchart showing an example of control executed by a control unit when determining whether a breathing filter is clogged in the electronic control device according to the fourth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, several embodiments will be described with reference to the drawings. In each embodiment, substantially the same components are designated by the same reference numerals, and the description thereof will be omitted. In the following description, the terms "first" and "second" are used simply to distinguish between components of the same type, and do not indicate superiority or inferiority of each component.

[0009] (First embodiment) First, the first embodiment will be described with reference to FIGS. The electronic control device 10 shown in Fig. 1 is configured as, for example, an engine ECU that controls an engine mounted on a vehicle. ECU is an abbreviation for Electronic Control Unit. The electronic control device 10 has a waterproof structure and is installed, for example, in an engine compartment of the vehicle. The electronic control device 10 includes a housing 20, a circuit board 30, and a breathing filter 40.

[0010] The housing 20 is formed in a substantially rectangular container shape from, for example, a combination of synthetic resin and metal. The housing 20 has an accommodation space 21 formed therein. The housing 20 also has a through-hole 22. The through-hole 22 is formed by penetrating the wall surface of the housing 20 in the thickness direction. The through-hole 22 connects the inside and outside of the housing 20.

[0011] The circuit board 30 is accommodated in the accommodation space 21 of the housing 20. The circuit board 30 is fixed to the housing 20 by, for example, screw fastening or adhesive. The circuit board 30 has a substrate 31 and electronic components 32. The substrate 31 is configured as a so-called printed circuit board. The electronic components 32 are mounted on the substrate 31. The electronic components 32 may be mounted on one side or both sides of the substrate 31.

[0012] The electronic components 32 include a heat generating element 321 and a microcomputer that constitutes a control unit 322. The heat generating element 321 is a component that generates a lot of heat and includes, for example, a switching element such as an IGBT or a MOSFET. The control unit 322 realizes predetermined functions by executing a program stored in a ROM or the like (not shown). The control unit 322 has a function of controlling the drive of well-known components such as a fuel injection valve, a throttle valve, and an ignition device as the load 90. The controls performed by the control unit 322 include control of the engine fuel injection amount, control of the air-fuel ratio, control of ignition timing, etc.

[0013] The electronic control device 10 includes a connector 33. The connector 33 is mounted on the circuit board 30, with one end housed inside the housing 20 and the other end exposed to the outside of the housing 20 through an opening (not shown) formed in the housing 20. The connector 33 has a plurality of terminals 331. The terminals 331 are made of, for example, a conductive metal, and electrically connect the circuit board 30 to an external device (not shown). The terminals 331 are provided on one end of the connector 33 and are mounted on the board 31.

[0014] The breathing filter 40 is provided in a portion of the housing 20 corresponding to the through-hole 22. The breathing filter 40 is attached to the housing 20 in a watertight manner, for example by snap-fitting. The breathing filter 40 allows ventilation between the housing space 21 and the outside via the through-hole 22, and prevents liquid from passing through the through-hole 22 from the outside and entering the housing space 21. The breathing filter 40 is configured to maintain equilibrium between the air pressure in the housing space 21 and the outside air pressure.

[0015] The breathing filter 40 has a main body 41, a breathing membrane 42, and a cover 43. The main body 41 is formed in a cylindrical shape and is attached to the housing 20 while being inserted through the through-hole 22. The outer shape of the main body 41 is formed to correspond to the shape of the through-hole. The inner peripheral surface of the main body 41 forms a path for ventilation between the accommodation space 21 and the outside.

[0016] The breathing membrane 42 is located outside the housing 20 and is provided so as to close one opening of the main body 41, in this case the opening on the exterior side of the housing 20. The breathing membrane 42 is breathable and waterproof. That is, the breathing membrane 42 allows gas to pass through while preventing liquid from passing through. The breathing membrane 42 may be a porous membrane formed using, for example, fluororesin or polyolefin. The breathing membrane 42 is fixed to the main body 41 by, for example, an adhesive or the like.

[0017] The cover 43 is formed, for example, in the shape of a box with one side open, and covers the breathing membrane 42. A gap is secured between the cover 43 and the breathing membrane 42. The cover 43 is intended to protect the breathing membrane 42.

[0018] For example, when the engine starts and the circuit board 30 operates, the internal temperature of the housing 20 rises due to the heat generated by the heating element 321, and the air pressure inside the housing 20 rises. At this time, pressure acts on the breathing membrane 42 toward the outside of the accommodation space 21, and the expanded air inside the housing 20 is released to the outside. On the other hand, for example, when the engine stops and the operation of the circuit board 30 stops, the internal temperature of the housing 20 drops, and the air pressure inside the housing 20 drops. At this time, pressure acts on the breathing membrane 42 toward the inside of the accommodation space 21, and outside air is drawn into the housing 20. In this way, the breathing filter 40 maintains equilibrium between the air pressure inside and outside the housing 20.

[0019] As shown in Fig. 2, the electronic control device 10 includes an atmospheric pressure sensor 51, a timing unit 52, and a memory unit 53. The atmospheric pressure sensor 51, the timing unit 52, and the memory unit 53 are electrically connected to the control unit 322. The atmospheric pressure sensor 51 has a function of detecting the atmospheric pressure inside the housing 20. The atmospheric pressure sensor 51 is mounted on the substrate 31 as shown in Fig. 1. The control unit 322 controls the load 90 based on the detection result of the atmospheric pressure sensor 51, i.e., the measurement value P.

[0020] The timing unit 52 has a function of acquiring the time at any point in time, for example. The time means, for example, an absolute time such as an hour, minute, and second, or a relative time based on a certain point in time. The timing unit 52 may also have a function of measuring the elapsed time from a certain reference point in time. The time means the length of time from one point in time to another. The memory unit 53 is composed of, for example, a non-volatile memory medium, and is configured to be able to store various information that is referenced or updated by the control unit 322 and used in the electronic control device 10.

[0021] The control unit 322 is electrically connected to the notification device 91. The notification device 91 has a function of notifying a user, for example, a vehicle driver, of predetermined information. The notification device 91 includes a display unit for visually presenting information to the driver. The display unit can be configured, for example, with a liquid crystal panel or a warning lamp. The notification device 91 may also audibly present information to the driver by sound, and can be configured, for example, to include a speaker.

[0022] 3 shows the change in air pressure inside the housing 20 over time depending on the state of the breathing membrane 42 of the breathing filter 40 on a graph with the horizontal axis representing time and the vertical axis representing the air pressure inside the housing 20. Under normal conditions where the breathing membrane 42 is not clogged, the air pressure inside the housing 20 gradually increases from an initial air pressure P0 at startup as the temperature inside the housing 20 rises due to operation of the circuit board 30, for example, from time T1 when the engine is started, as shown by the dashed line in FIG. 3. Thereafter, when the air pressure inside the housing 20 reaches a predetermined pressure, air inside the housing 20 is released from the breathing filter 40, and the internal air pressure begins to decrease, gradually approaching the initial air pressure P0.

[0023] On the other hand, when the breathing membrane 42 becomes clogged, the air pressure P0' inside the housing 20 after a predetermined time t has elapsed since startup will be higher than the air pressure inside the housing 20 after the predetermined time t has elapsed under normal conditions, due to the effect of a decrease in the amount of air passing through the breathing membrane 42, as shown by the solid line in Fig. 3. If the control unit 322 controls the load 90 based on the air pressure P0' inside the housing 20 due to clogging of the breathing membrane 42, there is a risk that inappropriate control will be performed, which may result in a deterioration in drivability.

[0024] Therefore, the control unit 322 determines that there is an abnormality in the breathing filter 40 when the pressure difference between the first pressure P1 detected by the atmospheric pressure sensor 51 when the electronic control device 10 is started and the second pressure P2 detected by the atmospheric pressure sensor 51 after a predetermined time t has elapsed since the start-up exceeds a set value ΔP. Furthermore, when the control unit 322 determines that there is an abnormality in the breathing filter 40, it executes correction control to correct the measured value P of the atmospheric pressure sensor 51 to the atmospheric pressure value of the first pressure P1. In other words, when the atmospheric pressure value inside the housing 20 cannot be accurately obtained due to clogging of the breathing filter 40, the control unit 322 corrects the measured value P of the atmospheric pressure sensor 51 to the first pressure P and controls the load 90.

[0025] The first pressure P is, for example, the atmospheric pressure value inside the housing 20 when the engine is started, and is the atmospheric pressure value when the pressure difference between the inside and outside of the housing 20 is balanced, and is therefore a safer value for performing normal control. Therefore, by controlling the load 90 using the atmospheric pressure value corrected to the first pressure P, it is possible to avoid the execution of inappropriate control based on an atmospheric pressure value that is erroneously detected due to clogging of the breathing membrane 42.

[0026] An atmospheric pressure value other than the first pressure P may be used as a correction value for the measured value P. The range of the correction value is between the first pressure P1 and the atmospheric pressure value obtained by adding the set value ΔP to the first pressure P1, and more preferably between the first pressure P1 and the atmospheric pressure value obtained by adding the first pressure P1 to a value equal to or less than half the set value ΔP.

[0027] Next, an example of the control content executed by the control unit 322 will be described with reference to Fig. 4. For example, when the engine starts (Start in Fig. 4), the control unit 322 acquires the first pressure P1 using the atmospheric pressure sensor 51 in step S11. Next, the control unit 322 stores the acquired first pressure P1 in the memory unit 53 in step S12. The control unit 322 proceeds to the process in step S13, and controls the timer unit 52 to start measuring the elapsed time.

[0028] Thereafter, in step S14, the control unit 322 determines whether a predetermined time t has elapsed since the elapsed time was measured. If the predetermined time t has elapsed (YES in step S14), the control unit 322 proceeds to step S15, where the control unit 322 acquires the second pressure P2 using the atmospheric pressure sensor 51. Next, the control unit 322 proceeds to step S16, where the control unit 322 determines whether the pressure difference between the second pressure P2 and the first pressure P1 has exceeded a set value ΔP. If the pressure difference has not exceeded the set value ΔP (NO in step S16), the control unit 322 proceeds to step S18, where the control unit 322 controls the timer unit 52 to stop measuring the elapsed time, and ends the series of control steps (END).

[0029] On the other hand, if the pressure difference between the second pressure P2 and the first pressure P1 exceeds the set value ΔP (YES in step S16), the control unit 322 determines that there is an abnormality in the breathing filter 40, and in step S17 corrects the measurement value P of the atmospheric pressure sensor 51 to the first pressure P1. Therefore, the control unit 322 can control the load 90 based on the corrected measurement value, i.e., the first pressure P1. Thereafter, the control unit 322 proceeds to step S18 and proceeds with the subsequent processes.

[0030] According to the embodiment described above, the electronic control device 10 includes a housing 20, a breathing filter 40, an atmospheric pressure sensor 51, and a control unit 322. The breathing filter 40 is provided in the housing 20 and is breathable and waterproof. The atmospheric pressure sensor 51 detects the atmospheric pressure inside the housing 20. The control unit 322 controls the driving of the load 90. The control unit 322 determines that there is an abnormality in the breathing filter 40 when the pressure difference between a first pressure P1 detected by the atmospheric pressure sensor 51 at startup and a second pressure P2 detected by the atmospheric pressure sensor 51 after a predetermined time t has elapsed since startup exceeds a set value ΔP.

[0031] This makes it possible to identify an abnormality, such as clogging, in the breathing filter 40 based on the atmospheric pressure detected by the atmospheric pressure sensor 51. This makes it possible to identify clogging of the breathing filter 40 early on without having to check the breathing filter 40 directly.

[0032] The control unit 322 controls the load 90 based on the measured value P of the atmospheric pressure sensor 51, and if it determines that there is an abnormality in the breathing filter 40, it executes correction control to correct the measured value P of the atmospheric pressure sensor 51 to the atmospheric pressure value of the first pressure P1. Here, if it is determined that there is an abnormality in the breathing filter 40, it is assumed that the breathing filter 40 is clogged, and the atmospheric pressure value P detected by the atmospheric pressure sensor 51 may be inaccurate. In this case, if the load 90 is controlled based on the atmospheric pressure value P detected by the atmospheric pressure sensor 51, inappropriate control may be executed, which may result in a deterioration in drivability.

[0033] Therefore, when it is determined that there is an abnormality in the breathing filter 40, the measured value P is corrected to the first pressure P1, which is the atmospheric pressure value at the time of startup, and the corrected measured value P1 is used to control the load 90, thereby enabling temporary normal control. This prevents inappropriate control from being performed, thereby suppressing deterioration of drivability.

[0034] (Second embodiment) Next, a second embodiment will be described with reference to Fig. 5. This second embodiment differs from the first embodiment in the control content of the control unit 322. In the first embodiment, the control unit 322 executes correction control when it determines that there is an abnormality in the breathing filter 40. In contrast, in the second embodiment, when it determines that there is an abnormality in the breathing filter 40, the control unit 322 uses the alarm device 91 to notify that there is an abnormality in the breathing filter 40.

[0035] In this second embodiment, the control unit 322 executes the control contents shown in Fig. 5 instead of the control contents shown in Fig. 4. In the control contents shown in Fig. 5, step S21 is executed instead of step S17 shown in Fig. 4. Specifically, if the pressure difference between the second pressure P2 and the first pressure P1 exceeds the set value ΔP (YES in step S16), the control unit 322 shifts the process to step S21 and uses the alarm device 91 to notify that the breathing filter 40 is abnormal.

[0036] If the notification device 91 is configured to include, for example, a warning lamp, the control unit 322 can turn on the warning lamp to notify the driver that there is an abnormality in the breathing filter 40. Also, if the notification device 91 is configured to include, for example, a speaker, the control unit 322 can notify the driver that there is an abnormality in the breathing filter 40 by generating a warning sound from the speaker.

[0037] According to the second embodiment, by notifying the driver that there is an abnormality in the breathing filter 40, it is possible to prompt the driver to inspect or replace the breathing filter 40. This improves the maintainability of the electronic control device 10.

[0038] (Third embodiment) Next, a third embodiment will be described with reference to FIG. 6. This third embodiment differs from the above-described embodiments in the control content of the control unit 322. In this embodiment, the control unit 322 determines whether the breathing filter 40 is abnormal multiple times, and executes correction control when the number of times N that it has been determined to be abnormal exceeds a preset number Ns. The set number Ns is not particularly limited, but is preferably about two or three times. This is because if an abnormality in the breathing filter 40 is repeatedly determined two or three times, it is highly likely that the breathing filter 40 is clogged.

[0039] In this third embodiment, the control unit 322 executes the control contents shown in Fig. 6 instead of the control contents shown in Fig. 4. The control contents shown in Fig. 6 are the same as the control contents shown in Fig. 4, but with steps A11 to A13 added. Specifically, if the pressure difference between the second pressure P2 and the first pressure P1 does not exceed the set value ΔP (NO in step S16), the control unit 322 shifts the process to step A11, resets the count of the number of errors N, which is the number of times an abnormality in the breathing filter 40 has been determined (step A11), and executes the processes from step S18 onwards.

[0040] On the other hand, if the pressure difference between the second pressure P2 and the first pressure P1 exceeds the set value ΔP (YES in step S16), the control unit 322 proceeds to step A12, increments the number of errors N by 1, and proceeds to step A13. Then, in step A13, the control unit 322 determines whether the number of errors N has exceeded the set number of errors Ns.

[0041] If the number of errors N does not exceed the set number of times Ns (NO in step A13), the control unit 322 shifts the process to step S18. On the other hand, if the number of errors N exceeds the set number of times Ns (YES in step A13), the control unit 322 shifts the process to step S17, determines that there is an abnormality in the breathing filter 40, and corrects the measurement value P of the atmospheric pressure sensor 51 to the first pressure P1. Thereafter, the control unit 322 shifts the process to step S18, controls the timer unit 52 to stop measuring the elapsed time, and ends the series of controls (END).

[0042] According to the third embodiment, by determining whether there is an abnormality in the breathing filter 40 multiple times, it is possible to prevent erroneous detection of the atmospheric pressure value inside the housing 20 due to, for example, a sudden change in the external air pressure. This makes it possible to more accurately detect clogging of the breathing filter 40. As a result, it is possible to prevent inappropriate control from being performed due to clogging of the breathing filter 40.

[0043] (Fourth embodiment) Next, a fourth embodiment will be described with reference to Figures 7 and 8. This fourth embodiment differs from the above-described embodiments in that the electronic control device 10 is equipped with a temperature sensor 54. The temperature sensor 54 has a function of detecting the temperature inside the housing 20. As shown in Figure 7, the temperature sensor 54 is mounted on the substrate 31 and is electrically connected to the control unit 322.

[0044] In this embodiment, the control unit 322 determines that an abnormality exists in the breathing filter 40 when the ratio of the pressure difference between the first pressure P1 and the second pressure P2 to the temperature difference between the first temperature T1 detected by the temperature sensor 54 at startup and the second temperature T2 detected by the temperature sensor 54 after a predetermined time t has elapsed exceeds a set value δ. In other words, the control unit 322 determines that an abnormality exists in the breathing filter 40 based on the detection results of the atmospheric pressure sensor 51 and the temperature sensor 54.

[0045] In the fourth embodiment, the control unit 322 executes the control content shown in Fig. 8. Specifically, when the engine is started (Start in Fig. 8), for example, the control unit 322 acquires a first pressure P1 using the atmospheric pressure sensor 51 and acquires a first temperature T1 using the temperature sensor 54 in step S31. Next, the control unit 322 stores the acquired first pressure P1 and first temperature T1 in the memory unit 53 in step S32. The control unit 322 proceeds to the process in step S33 and controls the timer unit 52 to start measuring the elapsed time.

[0046] Thereafter, in step S34, the control unit 322 determines whether a predetermined time t has elapsed since the elapsed time was measured. If the predetermined time t has elapsed (YES in step S34), the control unit 322 proceeds to step S35, where it acquires the second pressure P2 using the atmospheric pressure sensor 51 and acquires the second temperature T2 using the temperature sensor 54.

[0047] Next, the control unit 322 proceeds to step S36, where it determines whether the ratio of the pressure difference between the first pressure P1 and the second pressure P2 to the temperature difference between the first temperature T1 and the second temperature T2 exceeds a set value δ. If the ratio does not exceed the set value δ (NO in step S36), the control unit 322 proceeds to step S38, controls the timer unit 52 to stop measuring the elapsed time, and ends the series of control steps (END).

[0048] On the other hand, if the ratio of the pressure difference between the first pressure P1 and the second pressure P2 to the temperature difference between the first temperature T1 and the second temperature T2 exceeds the set value δ (YES in step S36), the control unit 322 determines that there is an abnormality in the breathing filter 40, and corrects the measurement value P of the atmospheric pressure sensor 51 to the first pressure P1 in step S37. Thereafter, the control unit 322 proceeds to step S38 and proceeds with the subsequent processes.

[0049] According to the fourth embodiment, an abnormality, such as clogging, in the breathing filter 40 can be identified based on the atmospheric pressure value detected by the atmospheric pressure sensor 51 and the temperature detected by the temperature sensor 54. This allows clogging of the breathing filter 40 to be identified early on without having to directly check the breathing filter 40.

[0050] The above-described embodiments can be combined with each other, and only the characteristic features of two or more embodiments can be extracted and combined.

[0051] Although the present disclosure has been described with reference to the embodiments, it is understood that the present disclosure is not limited to the embodiments or structures. The present disclosure also encompasses various modifications and equivalent modifications. In addition, various combinations and forms, including only one element, more than one element, or less than one element, are also within the scope and spirit of the present disclosure. [Explanation of symbols]

[0052] 10...Electronic control device, 20...Housing, 322...Control unit, 40...Breathing filter, 51...Atmospheric pressure sensor, 54...Temperature sensor, 90...Load, 91...Alarm device

Claims

1. A housing (20); a breathable and waterproof breathing filter (40) provided in the housing; an atmospheric pressure sensor (51) for detecting the atmospheric pressure inside the housing; a control unit (322) that controls the driving of the load (90); The control unit controlling the load based on the measurement value of the atmospheric pressure sensor; determining an abnormality in the breathing filter when a pressure difference between a first pressure detected by the atmospheric pressure sensor at the time of startup and a second pressure detected by the atmospheric pressure sensor after a predetermined time has elapsed since startup exceeds a set value; the determination of the abnormality is performed a plurality of times, and when the number of times that the abnormality is determined exceeds a preset number of times, a correction control is executed to correct the measurement value of the atmospheric pressure sensor to the atmospheric pressure value of the first pressure. Electronic control unit.

2. A housing (20); a breathable and waterproof breathing filter (40) provided in the housing; an atmospheric pressure sensor (51) for detecting the atmospheric pressure inside the housing; a temperature sensor (54) for detecting the temperature inside the housing; a control unit (322) that controls the load (90); the control unit determines that the breathing filter is abnormal when a ratio of a pressure difference between a first pressure detected by the atmospheric pressure sensor at the time of startup and a second pressure detected by the atmospheric pressure sensor after a predetermined time has elapsed since the startup, to a temperature difference between a first temperature detected by the temperature sensor at the time of startup and a second temperature detected by the temperature sensor after the predetermined time has elapsed, exceeds a set value. Electronic control unit.

3. The control unit controlling the load based on the measurement value of the atmospheric pressure sensor; When it is determined that the breathing filter has an abnormality, a correction control is executed to correct the measurement value of the atmospheric pressure sensor to the atmospheric pressure value of the first pressure. The electronic control device according to claim 2 .

4. When the control unit determines that the breathing filter is abnormal, the control unit uses an alarm device (91) to notify the user that the breathing filter is abnormal. The electronic control device according to claim 1 or 2.

5. the control unit performs the abnormality determination a plurality of times, and when the number of times the abnormality is determined exceeds a preset number of times, executes the correction control. The electronic control device according to claim 3 .

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