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WO2014132508A1 - Fuel filter diagnostic device and diagnostic method - Google Patents

Fuel filter diagnostic device and diagnostic method Download PDF

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Publication number
WO2014132508A1
WO2014132508A1 PCT/JP2013/081956 JP2013081956W WO2014132508A1 WO 2014132508 A1 WO2014132508 A1 WO 2014132508A1 JP 2013081956 W JP2013081956 W JP 2013081956W WO 2014132508 A1 WO2014132508 A1 WO 2014132508A1
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WO
WIPO (PCT)
Prior art keywords
fuel
control unit
atmospheric pressure
fuel filter
pressure
Prior art date
Application number
PCT/JP2013/081956
Other languages
French (fr)
Japanese (ja)
Inventor
泰治 高村
Original Assignee
日産ライトトラック株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 日産ライトトラック株式会社 filed Critical 日産ライトトラック株式会社
Priority to JP2015502717A priority Critical patent/JP5973055B2/en
Priority to CN201380073604.2A priority patent/CN105008707A/en
Publication of WO2014132508A1 publication Critical patent/WO2014132508A1/en

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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D41/00—Electrical control of supply of combustible mixture or its constituents
    • F02D41/22—Safety or indicating devices for abnormal conditions
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M37/00—Apparatus or systems for feeding liquid fuel from storage containers to carburettors or fuel-injection apparatus; Arrangements for purifying liquid fuel specially adapted for, or arranged on, internal-combustion engines
    • F02M37/22—Arrangements for purifying liquid fuel specially adapted for, or arranged on, internal-combustion engines, e.g. arrangements in the feeding system
    • F02M37/32—Arrangements for purifying liquid fuel specially adapted for, or arranged on, internal-combustion engines, e.g. arrangements in the feeding system characterised by filters or filter arrangements
    • F02M37/40—Arrangements for purifying liquid fuel specially adapted for, or arranged on, internal-combustion engines, e.g. arrangements in the feeding system characterised by filters or filter arrangements with means for detection of clogging
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D41/00—Electrical control of supply of combustible mixture or its constituents
    • F02D41/22—Safety or indicating devices for abnormal conditions
    • F02D2041/224—Diagnosis of the fuel system
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00—Road transport of goods or passengers
    • Y02T10/10—Internal combustion engine [ICE] based vehicles
    • Y02T10/40—Engine management systems

Definitions

  • the present invention relates to a fuel filter diagnostic device and a diagnostic method for diagnosing whether or not a fuel filter is clogged.
  • a fuel filter that removes foreign matters mixed in fuel is disposed in a fuel pipe that communicates a fuel tank and a fuel pump. If the fuel filter is clogged, fuel supply to the engine cannot be performed smoothly. For this reason, as described in Japanese Patent Application Laid-Open No. 2010-255517 (Patent Document 1), when the fuel pressure on the downstream side of the fuel filter becomes lower than a predetermined threshold value (fixed value), the fuel filter is considered. Techniques for diagnosing clogging have been proposed.
  • the predetermined threshold value for diagnosing whether or not the fuel filter is clogged is a fixed value, the fuel filter is clogged even though the fuel filter is not clogged. There was a risk of misdiagnosis.
  • an object of the present invention is to provide a fuel filter diagnostic device and a diagnostic method that make it difficult for erroneous diagnosis to occur even when atmospheric pressure changes.
  • a fuel filter diagnostic device includes: a negative pressure sensor that detects a fuel negative pressure downstream of a fuel filter disposed in a fuel pipe that communicates a fuel tank and a fuel pump; an atmospheric pressure sensor that detects an atmospheric pressure; And a control unit for reading the output signals of the negative pressure sensor and the atmospheric pressure sensor and diagnosing whether or not the fuel filter is clogged.
  • the control unit sets a threshold value according to the atmospheric pressure, and diagnoses that the fuel filter is clogged when the fuel pressure obtained by adding the fuel negative pressure and the atmospheric pressure becomes equal to or lower than the threshold value.
  • the threshold value is switched according to the atmospheric pressure, it is possible to prevent a misdiagnosis from occurring even if the atmospheric pressure changes.
  • FIG. 1 shows an example of a common rail system equipped with a fuel filter diagnostic device.
  • Fuel (light oil) stored in the fuel tank 100 is supplied to a supply pump 130 driven by a diesel engine ENG through a low-pressure fuel pipe 120 in which two fuel filters 110 are disposed.
  • the fuel supplied to the supply pump 130 is increased to a specified pressure by the supply pump 130 and supplied to the common rail 150 via the high-pressure fuel pipe 140. Further, the fuel that has been boosted to a specified pressure or higher by the supply pump 130 for some reason is returned to the fuel tank 100 via the fuel return pipe 160 when the built-in relief valve is opened.
  • the low-pressure fuel pipe 120 and the supply pump 130 are examples of the fuel pipe and the fuel pump, respectively.
  • the number of fuel filters 110 provided in the low-pressure fuel pipe 120 is not limited to two, but may be other numbers.
  • the fuel supplied to the common rail 150 is diverted to an injector 170 attached to the cylinder head of each cylinder, and the fuel injection amount and fuel according to the operating state of the diesel engine ENG It is injected into the combustion chamber at the injection timing. Further, the fuel that has not been injected from the injector 170 is returned to the fuel tank 100 via the fuel return pipe 160.
  • the common rail 150 is provided with a fuel pressure sensor 180 for detecting the pressure (fuel pressure) of the fuel accumulated therein, and an output signal thereof is input to a control unit 190 incorporating a computer.
  • the control unit 190 electronically controls the flow control valve built in the supply pump 130 so that the fuel pressure detected by the fuel pressure sensor 180 becomes a specified pressure.
  • a relief valve 200 that opens when the fuel pressure reaches the allowable upper limit value is attached to the common rail 150. The fuel flowing out from the relief valve 200 is returned to the fuel tank 100 via the fuel return pipe 160.
  • the control unit 190 determines the fuel injection amount and the fuel injection timing according to the operating state of the diesel engine ENG, and outputs an operation signal to the injector 170 at a predetermined timing.
  • a negative pressure sensor 210 for detecting a fuel negative pressure is attached to the low pressure fuel pipe 120 located downstream of the fuel filter 110, that is, between the fuel filter 110 and the supply pump 130. Therefore, the negative pressure sensor 210 detects the fuel negative pressure sucked from the fuel tank 100 via the fuel filter 110 in accordance with the operation of the supply pump 130.
  • the output signal of the negative pressure sensor 120 is input to the control unit 190.
  • the control unit 190 also detects an atmospheric pressure sensor 220 that detects atmospheric pressure, a rotation speed sensor 230 that detects the rotation speed of the diesel engine ENG (engine rotation speed), and a temperature (water temperature) of the cooling water of the diesel engine ENG. Each output signal of the water temperature sensor 240 is input.
  • the atmospheric pressure, the engine rotation speed, and the water temperature are not limited to the configuration that is directly detected by the atmospheric pressure sensor 220, the rotation speed sensor 230, and the water temperature sensor 240. You may make it read from the engine control unit (not shown) etc. which were made.
  • control unit 190 is an example of an alarm device attached to an instrument panel located in front of the driver's seat in order to notify the vehicle driver or the like that the fuel filter 110 is clogged.
  • a warning light 250 is connected.
  • control unit 190 executes a control program written in a non-volatile memory such as a flash ROM (Read Only Memory) to check whether or not the fuel filter 110 is clogged by the following logic. Diagnose.
  • a non-volatile memory such as a flash ROM (Read Only Memory)
  • diagnosis permission logic e.g., diagnosis permission logic
  • threshold setting logic e.g., threshold setting logic
  • filter diagnosis logic e.g., filter diagnosis logic.
  • FIG. 2 shows an example of a diagnosis permission logic for diagnosing whether or not a condition for diagnosing whether or not the fuel filter 110 is clogged.
  • the control unit 190 includes an atmospheric pressure condition (first condition) in which the atmospheric pressure is equal to or higher than a predetermined pressure, a rotation speed condition (second condition) in which the engine speed is within a predetermined range, and a water temperature at which the water temperature is equal to or higher than the predetermined temperature.
  • first condition in which the atmospheric pressure is equal to or higher than a predetermined pressure
  • second condition in which the engine speed is within a predetermined range
  • the flow rate of fuel supplied from the fuel tank 100 to the supply pump 130 is extremely small or extremely large.
  • a rotational speed condition in which the engine rotational speed is within a predetermined range is applied.
  • the possibility of misdiagnosis increases because the diesel engine ENG is not operating stably.
  • a water temperature condition is applied.
  • an abnormality such as a failure occurs in the negative pressure sensor 210
  • the fuel negative pressure downstream of the fuel filter 110 cannot be accurately detected. Therefore, an abnormality has occurred in the negative pressure sensor 210 as a diagnosis permission condition. Not applicable.
  • whether or not an abnormality has occurred in the negative pressure sensor 210 can be diagnosed by, for example, a known diagnostic function.
  • the clogging diagnosis of the fuel filter 110 is executed in a state where there is a high possibility that a misdiagnosis is performed. Can be suppressed, and the diagnostic accuracy can be improved. Note that it is also possible to apply that at least one of the atmospheric pressure condition, the rotation speed condition, the water temperature condition, and the sensor condition is satisfied as the diagnosis permission condition.
  • FIG. 3 shows an example of threshold setting logic for setting a first threshold for determining whether or not the fuel filter 110 is clogged.
  • the control unit 190 determines that the vehicle is traveling at a standard altitude that does not interfere with the clogging diagnosis of the fuel filter 110 if the atmospheric pressure is equal to or higher than the threshold value Hi. It is determined that the vehicle is traveling in a highland where the filter 110 is clogged.
  • the reason why the two threshold values Hi and Lo are used when determining the point where the vehicle is traveling is, for example, when the vehicle frequently travels between a lowland and a highland on a mountain road. This is to suppress control hunting.
  • the control unit 190 has a standard table and a high altitude table in which a control value suitable for the engine rotation speed is set in a nonvolatile memory, and according to a determination result of a point where the vehicle is traveling. The table is switched and a first threshold value corresponding to the engine speed is set.
  • the standard or high altitude table is appropriately switched according to the atmospheric pressure closely related to the altitude, and the atmospheric pressure is set by referring to the table and setting the first threshold value corresponding to the engine rotation speed. Even if changes, it is possible to make misdiagnosis difficult to occur.
  • FIG. 4 shows an example of filter diagnosis logic for diagnosing whether or not the fuel filter 110 is clogged.
  • the control unit 190 calculates the fuel pressure (absolute pressure) obtained by adding the atmospheric pressure and the fuel negative pressure, and the second threshold (which is equal to or less than the first threshold (variable value) or smaller than the first threshold ( It is determined whether or not it is less than (fixed value). If the control unit 190 determines that the fuel pressure is the first threshold value, the control unit 190 determines that the fuel filter 110 is clogged, and causes the warning light 250 attached to the instrument panel to move at a slow interval. Blink. Here, the control unit 190 outputs a first operation signal in order to blink the warning lamp 250 at a slow interval.
  • the control unit 190 determines that the fuel pressure is equal to or lower than the second threshold value, the vehicle driver or the like ignores the fuel filter 110 and drives the vehicle even though the fuel filter 110 is clogged. It is determined that the operation has been continued, and the warning lamp 250 is blinked at an early interval, and a control signal for limiting the output torque is output to the engine control unit.
  • the control unit 190 outputs the second operation signal in order to change the operation state of the warning lamp 250 and blink at an early interval.
  • the second threshold value may be a value with some margin from the limit pressure at which the fuel filter 110 is clogged and the diesel engine ENG stalls, for example.
  • FIG. 5 shows an example of the diagnosis permission process.
  • step 1 abbreviated as “S1” in the figure, the same applies hereinafter
  • the control unit 190 reads the atmospheric pressure from the atmospheric pressure sensor 220.
  • step 2 the control unit 190 determines whether or not the atmospheric pressure is equal to or higher than a predetermined pressure, in other words, whether or not the vehicle is traveling at a point with an extremely high altitude.
  • a predetermined pressure for example, in consideration of the output characteristics of the negative pressure sensor 210, a value having a margin more than a limit pressure at which a misdiagnosis may be performed can be set. If the control unit 190 determines that the atmospheric pressure is equal to or higher than the predetermined pressure, the control unit 190 proceeds to step 3 (Yes), whereas if it determines that the atmospheric pressure is lower than the predetermined pressure, the control unit 190 proceeds to step 9. (No).
  • step 3 the control unit 190 reads the engine rotation speed from the rotation speed sensor 230.
  • step 4 the control unit 190 determines whether or not the engine speed is within a predetermined range. Then, if the control unit 190 determines that the engine speed is within the predetermined range, the control unit 190 proceeds to step 5 (Yes), whereas if it determines that the engine speed is out of the predetermined range, the control unit 190 performs the process. Proceed to 9 (No).
  • step 5 the control unit 190 reads the water temperature from the water temperature sensor 240.
  • step 6 the control unit 190 determines whether or not the water temperature is equal to or higher than a predetermined temperature, in other words, whether or not the warm-up operation of the diesel engine ENG has been completed. If the control unit 190 determines that the water temperature is equal to or higher than the predetermined temperature, the control unit 190 proceeds to step 7 (Yes), while if the water temperature is determined to be lower than the predetermined temperature, the control unit 190 proceeds to step 9 (No). ).
  • step 7 the control unit 190 determines whether or not an abnormality such as a failure has occurred in the negative pressure sensor 210 using, for example, a self-diagnosis function of the sensor. If the control unit 190 determines that no abnormality has occurred in the negative pressure sensor 210, the process proceeds to step 8 (Yes), while if it determines that an abnormality has occurred in the negative pressure sensor 210, the process proceeds. To step 9 (No).
  • step 8 the control unit 190 sets the diagnosis permission flag stored in the nonvolatile memory to 1 (permission).
  • step 9 the control unit 190 sets the diagnosis permission flag stored in the nonvolatile memory to 0 (prohibited).
  • the diagnosis permission flag is set to 1 when all of the atmospheric pressure condition, the rotation speed condition, the water temperature condition, and the sensor condition are satisfied. On the other hand, when at least one of the atmospheric pressure condition, the rotation speed condition, the water temperature condition, and the sensor condition is not satisfied, the diagnosis permission flag is set to 0.
  • FIG. 6 shows an example of the threshold setting process.
  • the control unit 190 reads the atmospheric pressure from the atmospheric pressure sensor 220.
  • step 12 the control unit 190 determines whether or not the atmospheric pressure is equal to or higher than the threshold value Hi. If the control unit 190 determines that the atmospheric pressure is greater than or equal to the threshold value Hi, the control unit 190 proceeds to step 13 (Yes), whereas if it determines that the atmospheric pressure is less than the threshold value Hi, the process proceeds to step 14. Advance (No).
  • step 13 the control unit 190 switches the table for determining the first threshold according to the engine speed to the standard table.
  • step 14 the control unit 190 determines whether or not the atmospheric pressure is equal to or lower than a threshold Lo that is smaller than the threshold Hi. If the control unit 190 determines that the atmospheric pressure is equal to or lower than the threshold value Lo, the control unit 190 proceeds to step 15 (Yes), while if it determines that the atmospheric pressure is higher than the threshold value Lo, the process proceeds to step 17 ( No).
  • step 15 the control unit 190 switches the table for determining the first threshold value according to the engine rotation speed to a table for high altitude.
  • step 16 the control unit 190 reads the engine rotation speed from the rotation speed sensor 230.
  • step 17 the control unit 190 refers to the currently selected table and sets a first threshold value corresponding to the engine speed.
  • the table for determining the first threshold value is switched to the standard table, and when the atmospheric pressure becomes equal to or lower than the threshold value Lo, the first threshold value is changed.
  • the table for determination is switched to a table for high altitude. If the atmospheric pressure is higher than the threshold Lo and lower than the threshold Hi, the currently selected table is used as it is. Then, the currently selected table is referred to, and a first threshold value corresponding to the engine speed is set.
  • FIG. 7 shows an example of the filter diagnosis process.
  • the control unit 190 reads the diagnosis permission flag from the non-volatile memory, and whether or not the diagnosis permission flag is 1, that is, whether or not a diagnosis permission condition for diagnosing clogging of the fuel filter 110 is satisfied. Determine whether.
  • the control unit 190 advances the process to step 22 if it is determined that the diagnosis permission flag is 1 (permitted) (Yes), and performs the process if it is determined that the diagnosis permission flag is 0 (prohibited). End (No).
  • step 22 the control unit 190 reads the fuel negative pressure from the negative pressure sensor 210.
  • step 23 the control unit 190 reads the atmospheric pressure from the atmospheric pressure sensor 220.
  • control unit 190 calculates the fuel pressure (absolute pressure) of the low-pressure fuel pipe 120 located between the fuel filter 110 and the supply pump 130 by adding the fuel negative pressure and the atmospheric pressure.
  • step 25 the control unit 190 determines whether or not the fuel pressure is less than or equal to the second threshold, that is, whether or not the fuel filter 110 is clogged and the diesel engine ENG is about to stall. To do. Then, if the control unit 190 determines that the fuel pressure is equal to or lower than the second threshold value, the control unit 190 proceeds to step 26 (Yes), while if it determines that the fuel pressure is higher than the second threshold value, the process proceeds to step 28. Proceed to No (No).
  • step 26 the control unit 190 causes the warning light 250 attached to the instrument panel to blink at an early interval.
  • step 27 the control unit 190 outputs a control signal for limiting the output torque of the diesel engine ENG to the engine control unit.
  • step 28 the control unit 190 determines whether or not the fuel pressure is equal to or lower than the first threshold, in other words, whether or not the fuel filter 110 is clogged. If the control unit 190 determines that the fuel pressure is equal to or lower than the first threshold value, the control unit 190 advances the process to step 29 (Yes), whereas if it determines that the fuel pressure is higher than the first threshold value, the control unit 190 ends the process. (No).
  • step 29 the control unit 190 causes the warning light 250 attached to the instrument panel to blink at a slow interval.
  • the filter diagnosis process when the diagnosis permission flag is 1, it is diagnosed whether or not the fuel filter 110 is clogged. Therefore, the diagnosis in a state where a possibility of misdiagnosis is high is made. It is not executed, and the diagnostic accuracy can be improved. Further, when the fuel pressure obtained by adding the fuel pressure and the atmospheric pressure decreases to the first threshold value, it is determined that the fuel filter 110 is clogged. This utilizes the phenomenon that when the fuel filter 110 is clogged, the amount of fuel that can be supplied to the supply pump 130 decreases, and the fuel negative pressure on the downstream side of the fuel filter 110 decreases. When the fuel filter 110 is clogged, the warning light 250 blinks at a slow interval to notify the vehicle driver and the like. Accordingly, a vehicle driver who recognizes that the warning lamp 250 is blinking slowly can eliminate the clogging by replacing the element of the fuel filter 110, for example.
  • the warning lamp 250 blinks slowly but ignores the warning light 250 and continues to drive the vehicle, the fuel filter 110 is further clogged, and the fuel negative pressure on the downstream side further increases. descend.
  • the fuel pressure obtained by adding the fuel negative pressure and the atmospheric pressure becomes equal to or lower than the second threshold value, it is determined that the diesel engine ENG will soon be in a stalled state, and the warning lamp 250 blinks at an early interval. For this reason, the vehicle driver or the like can detect the danger that the diesel engine ENG will stall due to a change in the blinking state of the warning light 250, and can take prompt action.
  • control signal for limiting the output torque is output to the engine control unit along with the change of the blinking state of the warning lamp 250, the flow rate of the fuel flowing through the low-pressure fuel pipe 120 is reduced and the pressure loss is reduced. The time until the diesel engine ENG stalls can be increased. For this reason, it becomes possible to convey a vehicle to a service factory etc., for example, it can suppress that a vehicle stops on a road.
  • the limitation on the output torque may be that the vehicle can travel with no problem in traveling on a general road.
  • the fuel filter diagnostic device described above can be applied not only to diesel engines equipped with a common rail system, but also to other diesel engines, gasoline engines, and the like. Further, the number of tables for setting the first threshold is not limited to two according to the atmospheric pressure, and may be three or more.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Combined Controls Of Internal Combustion Engines (AREA)

Abstract

A fuel filter diagnostic device having: a negative pressure sensor that detects the negative fuel pressure downstream from a fuel filter provided in a fuel pipe connecting a fuel tank and a fuel pump; an atmospheric pressure sensor that detects the atmospheric pressure; and a control unit that reads the respective output signals from the negative pressure sensor and the atmospheric pressure sensor, and determines whether the fuel filter has become clogged. The control unit sets a first threshold value in accordance with the atmospheric pressure, and when the fuel pressure obtained by adding the negative fuel pressure and the atmospheric pressure is equal to or less than the first threshold value, the control unit determines that the fuel filter has become clogged.

Description

燃料フィルタの診断装置及び診断方法Fuel filter diagnostic apparatus and diagnostic method
　本発明は、燃料フィルタに目詰まりが発生したか否かを診断する、燃料フィルタの診断装置及び診断方法に関する。 The present invention relates to a fuel filter diagnostic device and a diagnostic method for diagnosing whether or not a fuel filter is clogged.
　エンジンの燃料供給システムにおいて、燃料タンクと燃料ポンプとを連通する燃料配管には、燃料に混入した異物を除去する燃料フィルタが配設されている。燃料フィルタに目詰まりが発生すると、エンジンへの燃料供給が円滑に行えなくなってしまう。このため、特開２０１０－２５５５１７号公報（特許文献１）に記載されるように、燃料フィルタの下流側の燃料圧力が所定の閾値（固定値）よりも低くなったときに、燃料フィルタに目詰まりが発生したと診断する技術が提案されている。 In a fuel supply system of an engine, a fuel filter that removes foreign matters mixed in fuel is disposed in a fuel pipe that communicates a fuel tank and a fuel pump. If the fuel filter is clogged, fuel supply to the engine cannot be performed smoothly. For this reason, as described in Japanese Patent Application Laid-Open No. 2010-255517 (Patent Document 1), when the fuel pressure on the downstream side of the fuel filter becomes lower than a predetermined threshold value (fixed value), the fuel filter is considered. Techniques for diagnosing clogging have been proposed.
特開２０１０－２５５５１７号公報JP 2010-255517 A
　ところで、車両が走行する標高が変化した場合、燃料フィルタの下流側における燃料の相対圧力が一定であっても、大気圧の変化に伴って燃料の絶対圧力が変化してしまう。このため、燃料フィルタに目詰まりが発生しているか否かを診断する所定の閾値が固定値であると、燃料フィルタに目詰まりが発生していないにもかかわらず、目詰まりが発生していると誤診断してしまうおそれがあった。 By the way, when the altitude at which the vehicle travels changes, even if the relative pressure of the fuel on the downstream side of the fuel filter is constant, the absolute pressure of the fuel changes as the atmospheric pressure changes. For this reason, when the predetermined threshold value for diagnosing whether or not the fuel filter is clogged is a fixed value, the fuel filter is clogged even though the fuel filter is not clogged. There was a risk of misdiagnosis.
　そこで、本発明は、大気圧が変化しても誤診断が起こり難くした、燃料フィルタの診断装置及び診断方法を提供することを目的とする。 Therefore, an object of the present invention is to provide a fuel filter diagnostic device and a diagnostic method that make it difficult for erroneous diagnosis to occur even when atmospheric pressure changes.
　燃料フィルタの診断装置は、燃料タンクと燃料ポンプとを連通する燃料配管に配設された燃料フィルタの下流側における燃料負圧を検出する負圧センサと、大気圧を検出する大気圧センサと、負圧センサ及び大気圧センサの出力信号を夫々読み込み、燃料フィルタに目詰まりが発生したか否かを診断するコントロールユニットと、を有する。そして、コントロールユニットは、大気圧に応じて閾値を設定し、燃料負圧と大気圧とを加算した燃料圧力が閾値以下になったときに、燃料フィルタに目詰まりが発生したと診断する。 A fuel filter diagnostic device includes: a negative pressure sensor that detects a fuel negative pressure downstream of a fuel filter disposed in a fuel pipe that communicates a fuel tank and a fuel pump; an atmospheric pressure sensor that detects an atmospheric pressure; And a control unit for reading the output signals of the negative pressure sensor and the atmospheric pressure sensor and diagnosing whether or not the fuel filter is clogged. The control unit sets a threshold value according to the atmospheric pressure, and diagnoses that the fuel filter is clogged when the fuel pressure obtained by adding the fuel negative pressure and the atmospheric pressure becomes equal to or lower than the threshold value.
　本発明によれば、大気圧に応じて閾値が切り替わるので、大気圧が変化しても誤診断が起こり難くすることができる。 According to the present invention, since the threshold value is switched according to the atmospheric pressure, it is possible to prevent a misdiagnosis from occurring even if the atmospheric pressure changes.
コモンレールシステムの一例を示す概要図である。It is a schematic diagram showing an example of a common rail system. 診断許可ロジックの一例を示すブロック図である。It is a block diagram which shows an example of a diagnosis permission logic. 閾値設定ロジックの一例を示すブロック図である。It is a block diagram which shows an example of a threshold value setting logic. フィルタ診断ロジックの一例を示すブロック図である。It is a block diagram which shows an example of a filter diagnostic logic. 診断許可処理の一例を示すフローチャートである。It is a flowchart which shows an example of a diagnosis permission process. 閾値設定処理の一例を示すフローチャートである。It is a flowchart which shows an example of a threshold value setting process. フィルタ診断処理の一例を示すフローチャートである。It is a flowchart which shows an example of a filter diagnostic process.
　以下、添付された図面を参照し、本発明を実施するための実施形態について詳述する。
　図１は、燃料フィルタの診断装置を備えたコモンレールシステムの一例を示す。 Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 shows an example of a common rail system equipped with a fuel filter diagnostic device.
　燃料タンク１００に貯蔵される燃料（軽油）は、２つの燃料フィルタ１１０が配設された低圧燃料配管１２０を介して、ディーゼルエンジンＥＮＧにより駆動されるサプライポンプ１３０に供給される。サプライポンプ１３０に供給された燃料は、サプライポンプ１３０によって規定圧力まで昇圧され、高圧燃料配管１４０を介してコモンレール１５０に供給される。また、サプライポンプ１３０において何らかの理由で規定圧力以上まで昇圧した燃料は、内蔵されたリリーフバルブが開弁することで、燃料戻し配管１６０を介して燃料タンク１００へと戻される。 Fuel (light oil) stored in the fuel tank 100 is supplied to a supply pump 130 driven by a diesel engine ENG through a low-pressure fuel pipe 120 in which two fuel filters 110 are disposed. The fuel supplied to the supply pump 130 is increased to a specified pressure by the supply pump 130 and supplied to the common rail 150 via the high-pressure fuel pipe 140. Further, the fuel that has been boosted to a specified pressure or higher by the supply pump 130 for some reason is returned to the fuel tank 100 via the fuel return pipe 160 when the built-in relief valve is opened.
　ここで、低圧燃料配管１２０及びサプライポンプ１３０が、夫々、燃料配管及び燃料ポンプの一例として挙げられる。また、低圧燃料配管１２０に配設される燃料フィルタ１１０は、２つに限らず、他の個数であってもよい。 Here, the low-pressure fuel pipe 120 and the supply pump 130 are examples of the fuel pipe and the fuel pump, respectively. Further, the number of fuel filters 110 provided in the low-pressure fuel pipe 120 is not limited to two, but may be other numbers.
　コモンレール１５０に供給された燃料は、例えば、４気筒のディーゼルエンジンＥＮＧの場合、各気筒のシリンダヘッドに取り付けられたインジェクタ１７０へと分流され、ディーゼルエンジンＥＮＧの運転状態に応じた燃料噴射量及び燃料噴射タイミングで燃焼室内へと噴射される。また、インジェクタ１７０から噴射されなかった燃料は、燃料戻し配管１６０を介して燃料タンク１００へと戻される。 For example, in the case of a four-cylinder diesel engine ENG, the fuel supplied to the common rail 150 is diverted to an injector 170 attached to the cylinder head of each cylinder, and the fuel injection amount and fuel according to the operating state of the diesel engine ENG It is injected into the combustion chamber at the injection timing. Further, the fuel that has not been injected from the injector 170 is returned to the fuel tank 100 via the fuel return pipe 160.
　コモンレール１５０には、ここに蓄圧される燃料の圧力（燃圧）を検出する燃圧センサ１８０が取り付けられ、その出力信号がコンピュータを内蔵したコントロールユニット１９０へと入力される。コントロールユニット１９０は、燃圧センサ１８０により検出された燃圧が規定圧力になるように、サプライポンプ１３０に内蔵された流量制御弁を電子制御する。また、コモンレール１５０には、燃圧が許容上限値に達すると開弁するリリーフバルブ２００が取り付けられる。リリーフバルブ２００から流出した燃料は、燃料戻し配管１６０を介して燃料タンク１００へと戻される。さらに、コントロールユニット１９０は、ディーゼルエンジンＥＮＧの運転状態に応じた燃料噴射量及び燃料噴射タイミングを決定し、所定タイミングでインジェクタ１７０に対して作動信号を出力する。 The common rail 150 is provided with a fuel pressure sensor 180 for detecting the pressure (fuel pressure) of the fuel accumulated therein, and an output signal thereof is input to a control unit 190 incorporating a computer. The control unit 190 electronically controls the flow control valve built in the supply pump 130 so that the fuel pressure detected by the fuel pressure sensor 180 becomes a specified pressure. In addition, a relief valve 200 that opens when the fuel pressure reaches the allowable upper limit value is attached to the common rail 150. The fuel flowing out from the relief valve 200 is returned to the fuel tank 100 via the fuel return pipe 160. Further, the control unit 190 determines the fuel injection amount and the fuel injection timing according to the operating state of the diesel engine ENG, and outputs an operation signal to the injector 170 at a predetermined timing.
　燃料フィルタ１１０の下流側、即ち、燃料フィルタ１１０とサプライポンプ１３０との間に位置する低圧燃料配管１２０には、燃料負圧を検出する負圧センサ２１０が取り付けられる。従って、負圧センサ２１０は、サプライポンプ１３０の作動に伴って、燃料フィルタ１１０を経由して燃料タンク１００から吸い上げられる燃料負圧を検出することとなる。負圧センサ１２０の出力信号は、コントロールユニット１９０へと入力される。また、コントロールユニット１９０には、大気圧を検出する大気圧センサ２２０、ディーゼルエンジンＥＮＧの回転速度（エンジン回転速度）を検出する回転速度センサ２３０、ディーゼルエンジンＥＮＧの冷却水の温度（水温）を検出する水温センサ２４０の各出力信号が入力される。なお、大気圧、エンジン回転速度及び水温は、大気圧センサ２２０、回転速度センサ２３０及び水温センサ２４０で直接検出する構成に限らず、例えば、ＣＡＮ（Controller Area Network）などの車載ネットワークを介して接続されたエンジンコントロールユニット（図示せず）などから読み込むようにしてもよい。 A negative pressure sensor 210 for detecting a fuel negative pressure is attached to the low pressure fuel pipe 120 located downstream of the fuel filter 110, that is, between the fuel filter 110 and the supply pump 130. Therefore, the negative pressure sensor 210 detects the fuel negative pressure sucked from the fuel tank 100 via the fuel filter 110 in accordance with the operation of the supply pump 130. The output signal of the negative pressure sensor 120 is input to the control unit 190. The control unit 190 also detects an atmospheric pressure sensor 220 that detects atmospheric pressure, a rotation speed sensor 230 that detects the rotation speed of the diesel engine ENG (engine rotation speed), and a temperature (water temperature) of the cooling water of the diesel engine ENG. Each output signal of the water temperature sensor 240 is input. Note that the atmospheric pressure, the engine rotation speed, and the water temperature are not limited to the configuration that is directly detected by the atmospheric pressure sensor 220, the rotation speed sensor 230, and the water temperature sensor 240. You may make it read from the engine control unit (not shown) etc. which were made.
　さらに、コントロールユニット１９０には、燃料フィルタ１１０に目詰まりが発生したことを車両運転者などに報知すべく、例えば、運転席の前方に位置するインストルメントパネルに取り付けられた警報装置の一例としての警告灯２５０が接続されている。 Further, the control unit 190 is an example of an alarm device attached to an instrument panel located in front of the driver's seat in order to notify the vehicle driver or the like that the fuel filter 110 is clogged. A warning light 250 is connected.
　そして、コントロールユニット１９０は、フラッシュＲＯＭ（Read Only Memory）などの不揮発性メモリに書き込まれた制御プログラムを実行することで、次のようなロジックによって、燃料フィルタ１１０に目詰まりが発生したか否かを診断する。ここで、燃料フィルタ診断ロジックとして、診断許可ロジック、閾値設定ロジック及びフィルタ診断ロジックが挙げられる。 Then, the control unit 190 executes a control program written in a non-volatile memory such as a flash ROM (Read Only Memory) to check whether or not the fuel filter 110 is clogged by the following logic. Diagnose. Here, examples of the fuel filter diagnosis logic include diagnosis permission logic, threshold setting logic, and filter diagnosis logic.
　図２は、燃料フィルタ１１０に目詰まりが発生しているか否かを診断する条件が成立しているか否かを診断する、診断許可ロジックの一例を示す。 FIG. 2 shows an example of a diagnosis permission logic for diagnosing whether or not a condition for diagnosing whether or not the fuel filter 110 is clogged.
　コントロールユニット１９０は、大気圧が所定圧力以上である大気圧条件（第１の条件）、エンジン回転速度が所定範囲内にある回転速度条件（第２の条件）、水温が所定温度以上である水温条件（第３の条件）、及び、負圧センサ２１０に故障などの異常が発生していないセンサ条件（第４の条件）のすべてが成立したときに、診断許可が成立したと判定する。即ち、車両が極端に標高の高い地点を走行している場合、大気圧が低くなって誤診断の可能性が高くなるので、診断許可条件として、大気圧が所定圧力以上である大気圧条件が適用される。エンジン回転速度が極低速域又は極高速域の場合、燃料タンク１００からサプライポンプ１３０へと供給される燃料流量が極少量又は極多量であるため、誤診断の可能性が高くなるので、診断許可条件として、エンジン回転速度が所定範囲内にある回転速度条件が適用される。また、ディーゼルエンジンＥＮＧの始動直後などの暖機運転中には、ディーゼルエンジンＥＮＧが安定して作動していないことから誤診断の可能性が高くなるので、診断許可条件として、水温が所定温度以上である水温条件が適用される。さらに、負圧センサ２１０に故障などの異常が発生している場合、燃料フィルタ１１０の下流側の燃料負圧を正確に検出できないため、診断許可条件として、負圧センサ２１０に異常が発生していないことが適用される。ここで、負圧センサ２１０に異常が発生しているか否かは、例えば、公知の診断機能により診断することができる。 The control unit 190 includes an atmospheric pressure condition (first condition) in which the atmospheric pressure is equal to or higher than a predetermined pressure, a rotation speed condition (second condition) in which the engine speed is within a predetermined range, and a water temperature at which the water temperature is equal to or higher than the predetermined temperature. When all of the condition (third condition) and the sensor condition (fourth condition) in which no abnormality such as failure has occurred in the negative pressure sensor 210 are satisfied, it is determined that the diagnosis permission is satisfied. In other words, when the vehicle is traveling at a point where the altitude is extremely high, the atmospheric pressure becomes low and the possibility of misdiagnosis increases. Applied. When the engine rotation speed is in the extremely low speed range or extremely high speed range, the flow rate of fuel supplied from the fuel tank 100 to the supply pump 130 is extremely small or extremely large. As a condition, a rotational speed condition in which the engine rotational speed is within a predetermined range is applied. In addition, during the warm-up operation such as immediately after the start of the diesel engine ENG, the possibility of misdiagnosis increases because the diesel engine ENG is not operating stably. A water temperature condition is applied. Furthermore, when an abnormality such as a failure occurs in the negative pressure sensor 210, the fuel negative pressure downstream of the fuel filter 110 cannot be accurately detected. Therefore, an abnormality has occurred in the negative pressure sensor 210 as a diagnosis permission condition. Not applicable. Here, whether or not an abnormality has occurred in the negative pressure sensor 210 can be diagnosed by, for example, a known diagnostic function.
　従って、診断許可条件として、大気圧条件、回転速度条件、水温条件及びセンサ条件を適用することで、誤診断がなされる可能性が高い状態において、燃料フィルタ１１０の目詰まり診断が実行されることを抑制し、その診断精度を向上させることができる。なお、診断許可条件として、大気圧条件、回転速度条件、水温条件及びセンサ条件の少なくとも１つの条件が成立していることを適用することもできる。 Therefore, by applying the atmospheric pressure condition, the rotation speed condition, the water temperature condition, and the sensor condition as the diagnosis permission condition, the clogging diagnosis of the fuel filter 110 is executed in a state where there is a high possibility that a misdiagnosis is performed. Can be suppressed, and the diagnostic accuracy can be improved. Note that it is also possible to apply that at least one of the atmospheric pressure condition, the rotation speed condition, the water temperature condition, and the sensor condition is satisfied as the diagnosis permission condition.
　図３は、燃料フィルタ１１０に目詰まりが発生しているか否かを判定するための第１の閾値を設定する、閾値設定ロジックの一例を示す。 FIG. 3 shows an example of threshold setting logic for setting a first threshold for determining whether or not the fuel filter 110 is clogged.
　コントロールユニット１９０は、大気圧が閾値Ｈｉ以上であれば、燃料フィルタ１１０の目詰まり診断に支障がない標準的な標高を走行していると判定し、大気圧が閾値Ｌｏ以下であれば、燃料フィルタ１１０の目詰まり診断に支障がある高地を走行していると判定する。ここで、車両が走行している地点を判定する際に、２つの閾値Ｈｉ及びＬｏを使用している理由は、例えば、車両が山道などを走行して低地と高地とを頻繁に行き来する場合などを考慮し、制御のハンチングを抑制するためである。また、コントロールユニット１９０は、エンジン回転速度に適合した制御値が設定された、標準用のテーブルと高地用のテーブルとを不揮発性メモリに持ち、車両が走行している地点の判定結果に応じてテーブルを切り替え、エンジン回転速度に応じた第１の閾値を設定する。 The control unit 190 determines that the vehicle is traveling at a standard altitude that does not interfere with the clogging diagnosis of the fuel filter 110 if the atmospheric pressure is equal to or higher than the threshold value Hi. It is determined that the vehicle is traveling in a highland where the filter 110 is clogged. Here, the reason why the two threshold values Hi and Lo are used when determining the point where the vehicle is traveling is, for example, when the vehicle frequently travels between a lowland and a highland on a mountain road. This is to suppress control hunting. In addition, the control unit 190 has a standard table and a high altitude table in which a control value suitable for the engine rotation speed is set in a nonvolatile memory, and according to a determination result of a point where the vehicle is traveling. The table is switched and a first threshold value corresponding to the engine speed is set.
　従って、標高と密接に関連する大気圧に応じて、標準用又は高地用のテーブルを適宜切り替えると共に、そのテーブルを参照してエンジン回転速度に応じた第１の閾値を設定することで、大気圧が変化しても誤診断が起こり難くすることができる。 Accordingly, the standard or high altitude table is appropriately switched according to the atmospheric pressure closely related to the altitude, and the atmospheric pressure is set by referring to the table and setting the first threshold value corresponding to the engine rotation speed. Even if changes, it is possible to make misdiagnosis difficult to occur.
　図４は、燃料フィルタ１１０に目詰まりが発生しているか否かを診断する、フィルタ診断ロジックの一例を示す。 FIG. 4 shows an example of filter diagnosis logic for diagnosing whether or not the fuel filter 110 is clogged.
　コントロールユニット１９０は、大気圧と燃料負圧とを加算した燃料圧力（絶対圧力）を算出し、これが第１の閾値（可変値）以下、又は、第１の閾値よりも小さい第２の閾値（固定値）以下であるか否かを判定する。そして、コントロールユニット１９０は、燃料圧力が第１の閾値であると判定すれば、燃料フィルタ１１０に目詰まりが発生したと判断し、インストルメントパネルに取り付けられた警告灯２５０をゆっくりとした間隔で点滅させる。ここで、コントロールユニット１９０は、警告灯２５０をゆっくりとした間隔で点滅させるために、第１の作動信号を出力する。 The control unit 190 calculates the fuel pressure (absolute pressure) obtained by adding the atmospheric pressure and the fuel negative pressure, and the second threshold (which is equal to or less than the first threshold (variable value) or smaller than the first threshold ( It is determined whether or not it is less than (fixed value). If the control unit 190 determines that the fuel pressure is the first threshold value, the control unit 190 determines that the fuel filter 110 is clogged, and causes the warning light 250 attached to the instrument panel to move at a slow interval. Blink. Here, the control unit 190 outputs a first operation signal in order to blink the warning lamp 250 at a slow interval.
　また、コントロールユニット１９０は、燃料圧力が第２の閾値以下であると判定すれば、燃料フィルタ１１０に目詰まりが発生したにもかかわらず、車両運転者などがこれを無視して車両を運転し続けたと判断し、警告灯２５０を早い間隔で点滅させると共に、エンジンコントロールユニットに対して出力トルクを制限する制御信号を出力する。ここで、コントロールユニット１９０は、警告灯２５０の作動状態を変更して早い間隔で点滅させるために、第２の作動信号を出力する。また、第２の閾値としては、例えば、燃料フィルタ１１０に目詰まりが発生してディーゼルエンジンＥＮＧがストールしてしまう限界圧力から多少の余裕を持たせた値とすることができる。 If the control unit 190 determines that the fuel pressure is equal to or lower than the second threshold value, the vehicle driver or the like ignores the fuel filter 110 and drives the vehicle even though the fuel filter 110 is clogged. It is determined that the operation has been continued, and the warning lamp 250 is blinked at an early interval, and a control signal for limiting the output torque is output to the engine control unit. Here, the control unit 190 outputs the second operation signal in order to change the operation state of the warning lamp 250 and blink at an early interval. Further, the second threshold value may be a value with some margin from the limit pressure at which the fuel filter 110 is clogged and the diesel engine ENG stalls, for example.
　次に、コントロールユニット１９０が、ディーゼルエンジンＥＮＧの始動又は電源投入を契機として所定時間ごとに繰り返し実行する、診断許可処理、閾値設定処理及びフィルタ診断処理について説明する。 Next, a diagnosis permission process, a threshold setting process, and a filter diagnosis process that the control unit 190 repeatedly executes at predetermined time intervals when the diesel engine ENG is started or turned on will be described.
　図５は、診断許可処理の一例を示す。
　ステップ１（図では「Ｓ１」と略記する。以下同様。）では、コントロールユニット１９０が、大気圧センサ２２０から大気圧を読み込む。 FIG. 5 shows an example of the diagnosis permission process.
In step 1 (abbreviated as “S1” in the figure, the same applies hereinafter), the control unit 190 reads the atmospheric pressure from the atmospheric pressure sensor 220.
　ステップ２では、コントロールユニット１９０が、大気圧が所定圧力以上であるか否か、要するに、車両が極端に標高の高い地点を走行しているか否かを判定する。ここで、所定圧力としては、例えば、負圧センサ２１０の出力特性などを考慮し、誤診断が行われる可能性がある限界圧力よりも若干余裕を持った値とすることができる。そして、コントロールユニット１９０は、大気圧が所定圧力以上であると判定すれば処理をステップ３へと進める一方（Ｙｅｓ）、大気圧が所定圧力未満であると判定すれば処理をステップ９へと進める（Ｎｏ）。 In step 2, the control unit 190 determines whether or not the atmospheric pressure is equal to or higher than a predetermined pressure, in other words, whether or not the vehicle is traveling at a point with an extremely high altitude. Here, as the predetermined pressure, for example, in consideration of the output characteristics of the negative pressure sensor 210, a value having a margin more than a limit pressure at which a misdiagnosis may be performed can be set. If the control unit 190 determines that the atmospheric pressure is equal to or higher than the predetermined pressure, the control unit 190 proceeds to step 3 (Yes), whereas if it determines that the atmospheric pressure is lower than the predetermined pressure, the control unit 190 proceeds to step 9. (No).
　ステップ３では、コントロールユニット１９０が、回転速度センサ２３０からエンジン回転速度を読み込む。 In step 3, the control unit 190 reads the engine rotation speed from the rotation speed sensor 230.
　ステップ４では、コントロールユニット１９０が、エンジン回転速度が所定範囲内であるか否かを判定する。そして、コントロールユニット１９０は、エンジン回転速度が所定範囲内であると判定すれば処理をステップ５へと進める一方（Ｙｅｓ）、エンジン回転速度が所定範囲を逸脱していると判定すれば処理をステップ９へと進める（Ｎｏ）。 In step 4, the control unit 190 determines whether or not the engine speed is within a predetermined range. Then, if the control unit 190 determines that the engine speed is within the predetermined range, the control unit 190 proceeds to step 5 (Yes), whereas if it determines that the engine speed is out of the predetermined range, the control unit 190 performs the process. Proceed to 9 (No).
　ステップ５では、コントロールユニット１９０が、水温センサ２４０から水温を読み込む。 In step 5, the control unit 190 reads the water temperature from the water temperature sensor 240.
　ステップ６では、コントロールユニット１９０が、水温が所定温度以上であるか否か、要するに、ディーゼルエンジンＥＮＧの暖機運転が終了しているか否かを判定する。そして、コントロールユニット１９０は、水温が所定温度以上であると判定すれば処理をステップ７へと進める一方（Ｙｅｓ）、水温が所定温度未満であると判定すれば処理をステップ９へと進める（Ｎｏ）。 In step 6, the control unit 190 determines whether or not the water temperature is equal to or higher than a predetermined temperature, in other words, whether or not the warm-up operation of the diesel engine ENG has been completed. If the control unit 190 determines that the water temperature is equal to or higher than the predetermined temperature, the control unit 190 proceeds to step 7 (Yes), while if the water temperature is determined to be lower than the predetermined temperature, the control unit 190 proceeds to step 9 (No). ).
　ステップ７では、コントロールユニット１９０が、例えば、センサの自己診断機能を利用し、負圧センサ２１０に故障などの異常が発生しているか否かを判定する。そして、コントロールユニット１９０は、負圧センサ２１０に異常が発生していないと判定すれば処理をステップ８へと進める一方（Ｙｅｓ）、負圧センサ２１０に異常が発生していると判定すれば処理をステップ９へと進める（Ｎｏ）。 In step 7, the control unit 190 determines whether or not an abnormality such as a failure has occurred in the negative pressure sensor 210 using, for example, a self-diagnosis function of the sensor. If the control unit 190 determines that no abnormality has occurred in the negative pressure sensor 210, the process proceeds to step 8 (Yes), while if it determines that an abnormality has occurred in the negative pressure sensor 210, the process proceeds. To step 9 (No).
　ステップ８では、コントロールユニット１９０が、不揮発性メモリに格納されている診断許可フラグを１（許可）に設定する。 In step 8, the control unit 190 sets the diagnosis permission flag stored in the nonvolatile memory to 1 (permission).
　ステップ９では、コントロールユニット１９０が、不揮発性メモリに格納されている診断許可フラグを０（禁止）に設定する。 In step 9, the control unit 190 sets the diagnosis permission flag stored in the nonvolatile memory to 0 (prohibited).
　かかる診断許可処理によれば、大気圧条件、回転速度条件、水温条件及びセンサ条件のすべてが成立したときには、診断許可フラグが１に設定される。一方、大気圧条件、回転速度条件、水温条件及びセンサ条件の少なくとも１つが成立しないときには、診断許可フラグが０に設定される。 According to such diagnosis permission processing, the diagnosis permission flag is set to 1 when all of the atmospheric pressure condition, the rotation speed condition, the water temperature condition, and the sensor condition are satisfied. On the other hand, when at least one of the atmospheric pressure condition, the rotation speed condition, the water temperature condition, and the sensor condition is not satisfied, the diagnosis permission flag is set to 0.
　図６は、閾値設定処理の一例を示す。
　ステップ１１では、コントロールユニット１９０が、大気圧センサ２２０から大気圧を読み込む。 FIG. 6 shows an example of the threshold setting process.
In step 11, the control unit 190 reads the atmospheric pressure from the atmospheric pressure sensor 220.
　ステップ１２では、コントロールユニット１９０が、大気圧が閾値Ｈｉ以上であるか否かを判定する。そして、コントトールユニット１９０は、大気圧が閾値Ｈｉ以上であると判定すれば処理をステップ１３へと進める一方（Ｙｅｓ）、大気圧が閾値Ｈｉ未満であると判定すれば処理をステップ１４へと進める（Ｎｏ）。 In step 12, the control unit 190 determines whether or not the atmospheric pressure is equal to or higher than the threshold value Hi. If the control unit 190 determines that the atmospheric pressure is greater than or equal to the threshold value Hi, the control unit 190 proceeds to step 13 (Yes), whereas if it determines that the atmospheric pressure is less than the threshold value Hi, the process proceeds to step 14. Advance (No).
　ステップ１３では、コントロールユニット１９０が、エンジン回転速度に応じた第１の閾値を決定するためのテーブルを、標準用のテーブルに切り替える。 In step 13, the control unit 190 switches the table for determining the first threshold according to the engine speed to the standard table.
　ステップ１４では、コントロールユニット１９０が、大気圧が閾値Ｈｉよりも小さい閾値Ｌｏ以下であるか否かを判定する。そして、コントロールユニット１９０は、大気圧が閾値Ｌｏ以下であると判定すれば処理をステップ１５へと進める一方（Ｙｅｓ）、大気圧が閾値Ｌｏより高いと判定すれば処理をステップ１７へと進める（Ｎｏ）。 In step 14, the control unit 190 determines whether or not the atmospheric pressure is equal to or lower than a threshold Lo that is smaller than the threshold Hi. If the control unit 190 determines that the atmospheric pressure is equal to or lower than the threshold value Lo, the control unit 190 proceeds to step 15 (Yes), while if it determines that the atmospheric pressure is higher than the threshold value Lo, the process proceeds to step 17 ( No).
　ステップ１５では、コントロールユニット１９０が、エンジン回転速度に応じた第１の閾値を決定するためのテーブルを、高地用のテーブルに切り替える。 In step 15, the control unit 190 switches the table for determining the first threshold value according to the engine rotation speed to a table for high altitude.
　ステップ１６では、コントロールユニット１９０が、回転速度センサ２３０からエンジン回転速度を読み込む。 In step 16, the control unit 190 reads the engine rotation speed from the rotation speed sensor 230.
　ステップ１７では、コントロールユニット１９０が、現在選択されているテーブルを参照し、エンジン回転速度に応じた第１の閾値を設定する。 In step 17, the control unit 190 refers to the currently selected table and sets a first threshold value corresponding to the engine speed.
　かかる閾値設定処理によれば、大気圧が閾値Ｈｉ以上になると、第１の閾値を決定するためのテーブルが標準用のテーブルに切り替えられ、大気圧が閾値Ｌｏ以下になると、第１の閾値を決定するためのテーブルが高地用のテーブルに切り替えられる。また、大気圧が閾値Ｌｏより高く、かつ、閾値Ｈｉ未満である場合には、現在選択されているテーブルがそのまま利用される。そして、現在選択されているテーブルが参照され、エンジン回転速度に応じた第１の閾値が設定される。 According to this threshold value setting process, when the atmospheric pressure becomes equal to or higher than the threshold value Hi, the table for determining the first threshold value is switched to the standard table, and when the atmospheric pressure becomes equal to or lower than the threshold value Lo, the first threshold value is changed. The table for determination is switched to a table for high altitude. If the atmospheric pressure is higher than the threshold Lo and lower than the threshold Hi, the currently selected table is used as it is. Then, the currently selected table is referred to, and a first threshold value corresponding to the engine speed is set.
　図７は、フィルタ診断処理の一例を示す。
　ステップ２１では、コントロールユニット１９０が、不揮発性メモリから診断許可フラグを読み出し、診断許可フラグが１であるか否か、要するに、燃料フィルタ１１０の目詰まりを診断する診断許可条件が成立しているか否かを判定する。そして、コントロールユンユニット１９０は、診断許可フラグが１（許可）であると判定すれば処理をステップ２２へと進める一方（Ｙｅｓ）、診断許可フラグが０（禁止）であると判定すれば処理を終了させる（Ｎｏ）。 FIG. 7 shows an example of the filter diagnosis process.
In step 21, the control unit 190 reads the diagnosis permission flag from the non-volatile memory, and whether or not the diagnosis permission flag is 1, that is, whether or not a diagnosis permission condition for diagnosing clogging of the fuel filter 110 is satisfied. Determine whether. The control unit 190 advances the process to step 22 if it is determined that the diagnosis permission flag is 1 (permitted) (Yes), and performs the process if it is determined that the diagnosis permission flag is 0 (prohibited). End (No).
　ステップ２２では、コントロールユニット１９０が、負圧センサ２１０から燃料負圧を読み込む。 In step 22, the control unit 190 reads the fuel negative pressure from the negative pressure sensor 210.
　ステップ２３では、コントロールユニット１９０が、大気圧センサ２２０から大気圧を読み込む。 In step 23, the control unit 190 reads the atmospheric pressure from the atmospheric pressure sensor 220.
　ステップ２４では、コントロールユニット１９０が、燃料負圧と大気圧とを加算することで、燃料フィルタ１１０とサプライポンプ１３０との間に位置する低圧燃料配管１２０の燃料圧力（絶対圧力）を算出する。 In step 24, the control unit 190 calculates the fuel pressure (absolute pressure) of the low-pressure fuel pipe 120 located between the fuel filter 110 and the supply pump 130 by adding the fuel negative pressure and the atmospheric pressure.
　ステップ２５では、コントロールユニット１９０が、燃料圧力が第２の閾値以下であるか否か、要するに、燃料フィルタ１１０に目詰まりが発生し、ディーゼルエンジンＥＮＧがもうすぐストールする状態であるか否かを判定する。そして、コントロールユニット１９０は、燃料圧力が第２の閾値以下であると判定すれば処理をステップ２６へと進める一方（Ｙｅｓ）、燃料圧力が第２の閾値より高いと判定すれば処理をステップ２８へと進める（Ｎｏ）。 In step 25, the control unit 190 determines whether or not the fuel pressure is less than or equal to the second threshold, that is, whether or not the fuel filter 110 is clogged and the diesel engine ENG is about to stall. To do. Then, if the control unit 190 determines that the fuel pressure is equal to or lower than the second threshold value, the control unit 190 proceeds to step 26 (Yes), while if it determines that the fuel pressure is higher than the second threshold value, the process proceeds to step 28. Proceed to No (No).
　ステップ２６では、コントロールユニット１９０が、インストルメントパネルに取り付けられた警告灯２５０を早い間隔で点滅させる。 In step 26, the control unit 190 causes the warning light 250 attached to the instrument panel to blink at an early interval.
　ステップ２７では、コントロールユニット１９０が、エンジンコントロールユニットに対して、ディーゼルエンジンＥＮＧの出力トルクを制限する制御信号を出力する。 In step 27, the control unit 190 outputs a control signal for limiting the output torque of the diesel engine ENG to the engine control unit.
　ステップ２８では、コントロールユニット１９０が、燃料圧力が第１の閾値以下であるか否か、要するに、燃料フィルタ１１０に目詰まりが発生したか否かを判定する。そして、コントロールユニット１９０は、燃料圧力が第１の閾値以下であると判定すれば処理をステップ２９へと進める一方（Ｙｅｓ）、燃料圧力が第１の閾値より高いと判定すれば処理を終了させる（Ｎｏ）。 In step 28, the control unit 190 determines whether or not the fuel pressure is equal to or lower than the first threshold, in other words, whether or not the fuel filter 110 is clogged. If the control unit 190 determines that the fuel pressure is equal to or lower than the first threshold value, the control unit 190 advances the process to step 29 (Yes), whereas if it determines that the fuel pressure is higher than the first threshold value, the control unit 190 ends the process. (No).
　ステップ２９では、コントロールユニット１９０が、インストルメントパネルに取り付けられた警告灯２５０をゆっくりとした間隔で点滅させる。 In step 29, the control unit 190 causes the warning light 250 attached to the instrument panel to blink at a slow interval.
　かかるフィルタ診断処理によれば、診断許可フラグが１であるとき、燃料フィルタ１１０に目詰まりが発生しているか否かが診断されるので、誤診断がなされる可能性が高い状態での診断が実行されず、その診断精度を向上させることができる。また、燃料圧力と大気圧とを加算した燃料圧力が第１の閾値まで低下すると、燃料フィルタ１１０に目詰まりが発生したと判断される。これは、燃料フィルタ１１０に目詰まりが発生すると、サプライポンプ１３０に供給可能な燃料が少なくなり、燃料フィルタ１１０の下流側における燃料負圧が低下する現象を利用したものである。そして、燃料フィルタ１１０に目詰まりが発生したときには、これを車両運転者などに報知すべく、警告灯２５０がゆっくりとした間隔で点滅される。従って、警告灯２５０がゆっくりと点滅していることを認識した車両運転者などは、例えば、燃料フィルタ１１０のエレメントを交換することで、その目詰まりを解消することができる。 According to the filter diagnosis process, when the diagnosis permission flag is 1, it is diagnosed whether or not the fuel filter 110 is clogged. Therefore, the diagnosis in a state where a possibility of misdiagnosis is high is made. It is not executed, and the diagnostic accuracy can be improved. Further, when the fuel pressure obtained by adding the fuel pressure and the atmospheric pressure decreases to the first threshold value, it is determined that the fuel filter 110 is clogged. This utilizes the phenomenon that when the fuel filter 110 is clogged, the amount of fuel that can be supplied to the supply pump 130 decreases, and the fuel negative pressure on the downstream side of the fuel filter 110 decreases. When the fuel filter 110 is clogged, the warning light 250 blinks at a slow interval to notify the vehicle driver and the like. Accordingly, a vehicle driver who recognizes that the warning lamp 250 is blinking slowly can eliminate the clogging by replacing the element of the fuel filter 110, for example.
　また、警告灯２５０がゆっくりと点滅しているにもかかわらず、これを無視して車両の運転を続行すると、燃料フィルタ１１０の目詰まりがさらに進行して、その下流側における燃料負圧がさらに低下する。そして、燃料負圧と大気圧とを加算した燃料圧力が第２の閾値以下になると、もうすぐディーゼルエンジンＥＮＧがストールする状態となると判断し、警告灯２５０を早い間隔で点滅させる。このため、車両運転者などは、警告灯２５０の点滅状態が変化することで、ディーゼルエンジンＥＮＧがストールする危険性を察知でき、迅速な対応をとることができる。また、警告灯２５０の点滅状態の変化と共に、エンジンコントロールユニットに対して出力トルクを制限する制御信号が出力されるので、低圧燃料配管１２０を流れる燃料の流量が減って圧力損失が小さくなることから、ディーゼルエンジンＥＮＧがストールするまでの時間を長くすることができる。このため、車両をサービス工場などに搬送することが可能となり、例えば、車両が路上で停車してしまうことを抑制することができる。出力トルクの制限は、一般道路における走行に支障がない程度で走行可能なものとすればよい。 Further, if the warning lamp 250 blinks slowly but ignores the warning light 250 and continues to drive the vehicle, the fuel filter 110 is further clogged, and the fuel negative pressure on the downstream side further increases. descend. When the fuel pressure obtained by adding the fuel negative pressure and the atmospheric pressure becomes equal to or lower than the second threshold value, it is determined that the diesel engine ENG will soon be in a stalled state, and the warning lamp 250 blinks at an early interval. For this reason, the vehicle driver or the like can detect the danger that the diesel engine ENG will stall due to a change in the blinking state of the warning light 250, and can take prompt action. Further, since the control signal for limiting the output torque is output to the engine control unit along with the change of the blinking state of the warning lamp 250, the flow rate of the fuel flowing through the low-pressure fuel pipe 120 is reduced and the pressure loss is reduced. The time until the diesel engine ENG stalls can be increased. For this reason, it becomes possible to convey a vehicle to a service factory etc., for example, it can suppress that a vehicle stops on a road. The limitation on the output torque may be that the vehicle can travel with no problem in traveling on a general road.
　以上説明した燃料フィルタの診断装置は、コモンレールシステムを備えたディーゼルエンジンに限らず、他のディーゼルエンジン、ガソリンエンジンなどにも適用することができる。また、第１の閾値を設定するためのテーブルは、大気圧に応じた２つに限らず、３つ以上であってもよい。 The fuel filter diagnostic device described above can be applied not only to diesel engines equipped with a common rail system, but also to other diesel engines, gasoline engines, and the like. Further, the number of tables for setting the first threshold is not limited to two according to the atmospheric pressure, and may be three or more.
　　１００　燃料タンク
　　１１０　燃料フィルタ
　　１２０　低圧燃料配管
　　１３０　サプライポンプ
　　１９０　コントロールユニット
　　２１０　負圧センサ
　　２２０　大気圧センサ
　　２３０　回転速度センサ
　　２４０　水温センサ
　　２５０　警告灯
　　ＥＮＧ　ディーゼルエンジン DESCRIPTION OF SYMBOLS 100 Fuel tank 110 Fuel filter 120 Low pressure fuel piping 130 Supply pump 190 Control unit 210 Negative pressure sensor 220 Atmospheric pressure sensor 230 Rotational speed sensor 240 Water temperature sensor 250 Warning light ENG Diesel engine

Claims (7)

  1. 　燃料タンクと燃料ポンプとを連通する燃料配管に配設された燃料フィルタの下流側における燃料負圧を検出する負圧センサと、
    　大気圧を検出する大気圧センサと、
    　前記負圧センサ及び前記大気圧センサの出力信号を夫々読み込み、前記燃料フィルタに目詰まりが発生したか否かを診断するコントロールユニットと、
    　を有し、
    　前記コントロールユニットが、
    　前記大気圧に応じた第１の閾値を設定し、
    　前記燃料負圧と前記大気圧とを加算した燃料圧力が前記第１の閾値以下になったときに、前記燃料フィルタに目詰まりが発生したと診断する、
    　ことを特徴とする燃料フィルタの診断装置。     A negative pressure sensor for detecting a fuel negative pressure downstream of a fuel filter disposed in a fuel pipe communicating with the fuel tank and the fuel pump;
    An atmospheric pressure sensor for detecting atmospheric pressure;
    A control unit that reads the output signals of the negative pressure sensor and the atmospheric pressure sensor, respectively, and diagnoses whether or not the fuel filter is clogged;
    Have
    The control unit is
    Setting a first threshold value according to the atmospheric pressure;
    Diagnosing that the fuel filter is clogged when the fuel pressure obtained by adding the fuel negative pressure and the atmospheric pressure is less than or equal to the first threshold value;
    A fuel filter diagnostic device.
  2. 　エンジンの回転速度を検出する回転速度センサを更に有し、
    　前記コントロールユニットが、大気圧ごとにエンジンの回転速度に適合した制御値が設定されたテーブルを参照し、前記大気圧及び前記回転速度に応じた第１の閾値を設定する、
    　ことを特徴とする請求項１に記載の燃料フィルタの診断装置。     A rotation speed sensor for detecting the rotation speed of the engine;
    The control unit refers to a table in which a control value adapted to the rotational speed of the engine is set for each atmospheric pressure, and sets a first threshold value corresponding to the atmospheric pressure and the rotational speed;
    The fuel filter diagnostic apparatus according to claim 1, wherein:
  3. 　エンジンの冷却水の温度を検出する水温センサを更に有し、
    　前記コントロールユニットが、前記大気圧が所定圧力以上である第１の条件、前記エンジンの回転速度が所定範囲内にある第２の条件、前記冷却水の温度が所定温度以上である第３の条件、かつ、前記負圧センサに異常が発生していない第４の条件の少なくとも１つの条件が成立したときに、前記燃料フィルタに目詰まりが発生しているか否かを診断する、
    　ことを特徴とする請求項２に記載の燃料フィルタの診断装置。     A water temperature sensor for detecting the temperature of the engine cooling water;
    The control unit includes a first condition in which the atmospheric pressure is equal to or higher than a predetermined pressure, a second condition in which the rotational speed of the engine is within a predetermined range, and a third condition in which the temperature of the cooling water is equal to or higher than a predetermined temperature. And diagnosing whether or not the fuel filter is clogged when at least one of the fourth conditions in which no abnormality has occurred in the negative pressure sensor is satisfied,
    3. The fuel filter diagnostic apparatus according to claim 2, wherein
  4. 　前記コントロールユニットが、前記燃料圧力が前記第１の閾値以下になったときに、警報装置を作動させる第１の作動信号を出力する、
    　ことを特徴とする請求項１～請求項３のいずれか１つに記載の燃料フィルタの診断装置。     The control unit outputs a first activation signal for activating an alarm device when the fuel pressure falls below the first threshold;
    The fuel filter diagnostic apparatus according to any one of claims 1 to 3, wherein
  5. 　前記コントロールユニットが、前記燃料圧力が前記第１の閾値より小さい第２の閾値以下になったときに、前記警報装置の作動状態を変更した第２の作動信号を出力する、
    　ことを特徴とする請求項４に記載の燃料フィルタの診断装置。     The control unit outputs a second operation signal that changes an operation state of the alarm device when the fuel pressure is equal to or lower than a second threshold value that is smaller than the first threshold value;
    The fuel filter diagnostic device according to claim 4, wherein
  6. 　前記コントロールユニットが、前記燃料圧力が前記第１の閾値より小さい第２の閾値以下になったときに、エンジンの出力トルクを制限する制御信号を出力する、
    　ことを特徴とする請求項１～請求項５のいずれか１つに記載の燃料フィルタの診断装置。     The control unit outputs a control signal for limiting an output torque of the engine when the fuel pressure falls below a second threshold value that is smaller than the first threshold value;
    6. The fuel filter diagnostic apparatus according to claim 1, wherein
  7. 　コントロールユニットが、
    　大気圧に応じて閾値を設定し、
    　燃料タンクと燃料ポンプとを連通する燃料配管に配設された燃料フィルタの下流側における燃料負圧と前記大気圧とを加算した燃料圧力が、前記閾値以下になったときに、前記燃料フィルタに目詰まりが発生したと診断する、
    　ことを特徴とする燃料フィルタの診断方法。     The control unit
    Set the threshold according to the atmospheric pressure,
    When the fuel pressure obtained by adding the fuel negative pressure on the downstream side of the fuel filter disposed in the fuel pipe communicating with the fuel tank and the fuel pump and the atmospheric pressure is equal to or lower than the threshold value, the fuel filter To diagnose clogging,
    A method for diagnosing a fuel filter.
PCT/JP2013/081956 2013-02-27 2013-11-27 Fuel filter diagnostic device and diagnostic method WO2014132508A1 (en)

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JP7310657B2 (en) * 2020-03-06 2023-07-19 トヨタ自動車株式会社 Fuel property diagnostic device
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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5935676U (en) * 1982-08-31 1984-03-06 日産自動車株式会社 Diesel engine fuel filter clogging warning device
JP2006283724A (en) * 2005-04-04 2006-10-19 Hitachi Constr Mach Co Ltd Fuel filter clogging detection device of construction machine
JP2010255517A (en) * 2009-04-24 2010-11-11 Kobelco Contstruction Machinery Ltd Engine control device

Family Cites Families (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH08200119A (en) * 1995-01-23 1996-08-06 Toyota Motor Corp Fuel injection amount controller of internal combustion engine
FR2787143B1 (en) * 1998-12-14 2001-02-16 Magneti Marelli France DETECTION OF FOULING OF A FUEL FILTER OF A SUPPLY CIRCUIT OF AN INTERNAL COMBUSTION ENGINE
JP2004068763A (en) * 2002-08-08 2004-03-04 Toyota Motor Corp Fuel supply control device of internal combustion engine
JP2005104392A (en) * 2003-10-01 2005-04-21 Komatsu Ltd Tank fuel purifier
JP4135666B2 (en) * 2004-03-24 2008-08-20 トヨタ自動車株式会社 Engine fuel supply control device
JP4407611B2 (en) * 2005-10-06 2010-02-03 株式会社デンソー Fuel injection control device
JP4306722B2 (en) * 2006-11-24 2009-08-05 トヨタ自動車株式会社 Fuel injection device
JP2010203330A (en) * 2009-03-04 2010-09-16 Denso Corp Device for diagnosing abnormality of fuel supply path
JP5168222B2 (en) * 2009-04-27 2013-03-21 株式会社デンソー Fuel injection device
JP2012122336A (en) * 2010-12-06 2012-06-28 Ud Trucks Corp Clogging determination device of air filter for internal combustion engine

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5935676U (en) * 1982-08-31 1984-03-06 日産自動車株式会社 Diesel engine fuel filter clogging warning device
JP2006283724A (en) * 2005-04-04 2006-10-19 Hitachi Constr Mach Co Ltd Fuel filter clogging detection device of construction machine
JP2010255517A (en) * 2009-04-24 2010-11-11 Kobelco Contstruction Machinery Ltd Engine control device

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