JP2009243304A - Filter clogging determination system and filter clogging determination device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a filter clogging determination system can determine the clogging of two filters and suppress the increase of the number of necessary sensors. <P>SOLUTION: In the filter clogging determination system, a first inlet pressure detection part detects first inlet pressure of a first filter. A first differential pressure detection part detects first differential pressure of the first filter. A deviation quantity calculation part refers first relation information of a first memory part and acquires reference first inlet pressure from the first differential pressure to calculate first inlet pressure deviation quantity. The reference first inlet pressure is the first inlet pressure while occurring no clogging at a second filter. The first inlet pressure deviation quantity is the difference between the reference first inlet pressure and the first inlet pressure detected by the first inlet pressure detection part. A second differential pressure acquisition part refers second relation information of a second memory part to acquire second differential pressure from the first inlet pressure deviation quantity. A clogging determination part determines the clogging of the first filter from the first differential pressure, and determines the clogging of the second filter from the second differential pressure. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a filter clogging determination system and a filter clogging determination device.

A filter is provided in a fuel supply path for supplying fuel to the fuel injection device of the engine in order to remove foreign matters in the fuel. When the filter is clogged, it is difficult to supply fuel normally. Therefore, in the conventional fuel supply device, clogging of the filter is monitored. For example, in the fuel supply device disclosed in Patent Document 1, a pressure sensor that detects the pressure of the fuel on the inlet side of the filter and the pressure of the fuel on the outlet side is provided, and the differential pressure between these pressures is monitored. Thus, it is determined whether or not the filter is clogged.
JP 2005-273535 A

  However, in the conventional fuel supply apparatus as described above, more pressure sensors are required when two filters are provided in the fuel supply path. That is, it is necessary to provide a pressure sensor for each filter in order to detect the pressure of the fuel on the inlet side and the outlet side of each filter. For this reason, the required number of sensors increases.

  An object of the present invention is to provide a filter clogging determination system and a filter clogging determination device capable of determining clogging of two filters and suppressing an increase in the required number of sensors.

  A filter clogging determination system according to a first invention includes a first filter, a second filter, a first inlet pressure detection unit, a first differential pressure detection unit, a first storage unit, a deviation amount calculation unit, A second storage unit; a second differential pressure acquisition unit; and a clogging determination unit. The first filter is provided in the fuel supply path. The second filter is provided upstream of the first filter in the fuel supply path. The first inlet pressure detector detects a first inlet pressure that is the pressure of fuel on the inlet side of the first filter. The first differential pressure detection unit detects a first differential pressure, which is a fuel pressure difference between the inlet side and the outlet side of the first filter. The first storage unit stores first relationship information. The first relationship information indicates the relationship between the first differential pressure and the reference first inlet pressure. The reference first inlet pressure is the first inlet pressure when the second filter is not clogged. The deviation amount calculation unit refers to the first relationship information, acquires a reference first inlet pressure corresponding to the first differential pressure detected by the first differential pressure detection unit, and calculates a first inlet pressure deviation amount. . The first inlet pressure deviation amount is a difference between the reference first inlet pressure and the first inlet pressure detected by the first inlet pressure detector. The second storage unit stores second relationship information. The second relationship information indicates the relationship between the first inlet pressure deviation amount and the second differential pressure. The second differential pressure is a fuel pressure difference between the inlet side and the outlet side of the second filter. The second differential pressure acquisition unit refers to the second relationship information and acquires the second differential pressure from the first inlet pressure deviation amount calculated by the deviation amount calculation unit. The clogging determination unit determines clogging of the first filter from the first differential pressure, and determines clogging of the second filter from the second differential pressure.

  In this filter clogging determination system, the first inlet pressure of the first filter is detected by the first inlet pressure detector. Further, the first differential pressure detector detects the first differential pressure. Then, the reference first inlet pressure corresponding to the detected first differential pressure is acquired by referring to the first relationship information. Next, a first inlet pressure deviation amount that is a difference between the reference first inlet pressure and the first inlet pressure is calculated. Then, the second relationship information is referred to, and the second differential pressure is acquired from the first inlet pressure deviation amount calculated by the deviation amount calculation unit. Thereby, the 1st differential pressure of the 1st filter and the 2nd differential pressure of the 2nd filter are acquired, and clogging of each filter is judged from these differential pressures.

  Thus, in this filter clogging determination system, the second differential pressure of the second filter can be accurately estimated from the first inlet pressure of the first filter and the first differential pressure. For this reason, an additional device for detecting the second differential pressure is not required. Thereby, clogging of two filters can be determined, and an increase in the required number of sensors can be suppressed.

  A filter clogging determination system according to a second invention is the filter clogging determination system according to the first invention, further comprising a display unit. The display unit outputs a predetermined warning display when the first differential pressure is larger than a predetermined first threshold value or when the second differential pressure is larger than a predetermined second threshold value.

  In this filter clogging determination system, a warning display is output by the display unit, so that it is possible to notify that the filter needs to be replaced.

  A filter clogging determination device according to a third aspect of the present invention is directed to a fuel supply system including a first filter, a second filter, a first inlet pressure detection unit, and a first differential pressure detection unit. It is an apparatus for determining clogging of the second filter. The first filter is provided in the fuel supply path. The second filter is provided upstream of the first filter in the fuel supply path. The first inlet pressure detector detects a first inlet pressure that is the pressure of fuel on the inlet side of the first filter. The first differential pressure detection unit detects a first differential pressure, which is a fuel pressure difference between the inlet side and the outlet side of the first filter. The filter clogging determination device includes a first storage unit, a deviation amount calculation unit, a second storage unit, a second differential pressure acquisition unit, and a clogging determination unit. The first storage unit stores first relationship information. The first relationship information indicates the relationship between the first differential pressure and the reference first inlet pressure. The reference first inlet pressure is the first inlet pressure when the second filter is not clogged. The deviation amount calculation unit refers to the first relationship information, acquires a reference first inlet pressure corresponding to the first differential pressure detected by the first differential pressure detection unit, and calculates a first inlet pressure deviation amount. . The first inlet pressure deviation amount is a difference between the reference first inlet pressure and the first inlet pressure detected by the first inlet pressure detector. The second storage unit stores second relationship information. The second relationship information indicates the relationship between the first inlet pressure deviation amount and the second differential pressure. The second differential pressure is a fuel pressure difference between the inlet side and the outlet side of the second filter. The second differential pressure acquisition unit refers to the second relationship information and acquires the second differential pressure from the first inlet pressure deviation amount calculated by the deviation amount calculation unit. The clogging determination unit determines clogging of the first filter from the first differential pressure, and determines clogging of the second filter from the second differential pressure.

  In this filter clogging determination device, the first inlet pressure of the first filter is detected by the first inlet pressure detector. Further, the first differential pressure detector detects the first differential pressure. Then, the reference first inlet pressure corresponding to the detected first differential pressure is acquired by referring to the first relationship information. Next, a first inlet pressure deviation amount that is a difference between the reference first inlet pressure and the first inlet pressure is calculated. Then, the second relationship information is referred to, and the second differential pressure is acquired from the first inlet pressure deviation amount. Thereby, the 1st differential pressure of the 1st filter and the 2nd differential pressure of the 2nd filter are acquired, and clogging of each filter is judged from these differential pressures.

  Thus, in this filter clogging determination device, the second differential pressure of the second filter can be accurately estimated from the first inlet pressure of the first filter and the first differential pressure. For this reason, an additional device for detecting the second differential pressure is not required. Thereby, clogging of two filters can be determined, and an increase in the required number of sensors can be suppressed.

  In the filter clogging determination system and the filter clogging determination device according to the present invention, the second differential pressure of the second filter can be accurately estimated from the first inlet pressure and the first differential pressure of the first filter. For this reason, an additional device for detecting the second differential pressure is not required. Thereby, clogging of two filters can be determined, and an increase in the required number of sensors can be suppressed.

1. Configuration 1-1. Overall Configuration FIG. 1 shows a fuel supply system 100 according to an embodiment of the present invention. The fuel supply system 100 is a system for supplying the fuel in the fuel tank 1 to the fuel injection device 11 of the engine, and is provided in a work vehicle such as a bulldozer, a hydraulic excavator, a wheel loader, or the like. The fuel supply system 100 includes a fuel tank 1, a second filter 2, a gear pump 3, a pressure feed pump 4, a first filter 5, a first pressure sensor 6, a second pressure sensor 7, and a filter clogging determination. A device 8, a feed pump 10, and a fuel injection device 11 are provided.

  The fuel tank 1 stores fuel therein. The fuel tank 1 is connected to the fuel injection device 11 by a fuel supply path 12, and the fuel in the fuel tank 1 is sent to the fuel injection device 11 through the fuel supply path 12. In FIG. 1, the arrow indicates the direction of fuel flow.

  The 2nd filter 2 is provided in the fuel supply path 12, and is provided in the upstream from the 1st filter 5 mentioned later. The 2nd filter 2 filters a foreign material from the fuel which passes.

  The gear pump 3 and the pressure pump 4 send the fuel in the fuel tank 1 to the fuel injection device 11. The pressure pump 4 discharges fuel at a predetermined flow rate. As a result, when the first filter 5 and the second filter 2 are not clogged, the pressure of the fuel on the inlet side of the first filter 5 (hereinafter referred to as “first inlet pressure PL”) is a predetermined steady pressure. Ps (see FIG. 4) is maintained.

  The first filter 5 is provided downstream of the second filter 2 and the pressure feed pump 4 in the fuel supply path 12. The 2nd filter 2 filters a foreign material from the fuel which passes.

  The first pressure sensor 6 detects the first inlet pressure P1in. The first inlet pressure P1in detected by the first pressure sensor 6 is sent as a detection signal to the control unit (see FIG. 2) of the filter clogging determination device 8.

  The second pressure sensor 7 detects a first outlet pressure P1out that is the pressure of the fuel on the outlet side of the first filter 5. The first outlet pressure P1out detected by the second pressure sensor 7 is sent to the control unit (see FIG. 2) as a detection signal.

  The filter clogging determination device 8 constitutes a filter clogging determination system together with the first filter 5, the second filter 2, the first pressure sensor 6, and the second pressure sensor 7. The filter clogging determination device 8 includes the first filter 5 and the second filter 2 based on the first inlet pressure P1in detected by the first pressure sensor 6 and the first outlet pressure P1out detected by the second pressure sensor 7. It is an apparatus which can determine clogging. The filter clogging determination device 8 will be described in detail later.

  The feed pump 10 supplies fuel to the fuel injection device 11.

  The fuel injection device 11 injects fuel into the engine. The fuel remaining without being injected in the fuel injection device 11 is returned to the pressure feed pump 4 by the first fuel circulation path 13. When the amount of fuel returned to the pressure pump 4 by the first fuel circulation path 13 is excessive, a part of the fuel is returned to the fuel tank 1 by the second fuel circulation path 14.

1-2. Configuration of Filter Clogging Determination Device 8 The filter clogging determination device 8 is based on the first inlet pressure P1in detected by the first pressure sensor 6 and the first outlet pressure P1out detected by the second pressure sensor 7. This is a device for determining clogging between the first filter 5 and the second filter 2. As illustrated in FIG. 2, the filter clogging determination device 8 includes a first storage unit 21, a second storage unit 22, a third storage unit 23, a control unit 24, and a display unit 25.

  The 1st memory | storage part 21 is an apparatus which memorize | stores data, and memorize | stores the 1st table (1st relationship information) as shown to Fig.3 (a). The first table is a table in which the first differential pressure dP1 and the reference first inlet pressure PL are associated with each other. The first table is obtained experimentally and stored in the first storage unit 21 in advance. The first differential pressure dP1 is a difference between the first inlet pressure P1in and the first outlet pressure P1out. The reference first inlet pressure PL is the first inlet pressure P1in in a state where the second filter 2 is not clogged. Here, in a state where the second filter 2 is not clogged, the first differential pressure dp1 and the reference first inlet pressure PL have a relationship as shown by a line L1 in FIG. That is, when the first filter 5 is clogged and it becomes difficult for the fuel to flow through the first filter 5, the first inlet pressure P1in on the upstream side of the first filter 5 increases. Accordingly, as the first differential pressure dp1 increases, the reference first inlet pressure PL also increases and becomes larger than the steady pressure Ps. In FIG. 4, Ps is a steady pressure in a state where the first filter 5 and the second filter 2 are not clogged. The first table is a table of the relationship between the first differential pressure dp1 indicated by the line L1 and the reference first inlet pressure PL.

  The 2nd memory | storage part 22 is an apparatus which memorize | stores data, and has memorize | stored the 2nd table (2nd relationship information). As shown in FIG. 3B, the second table is a table in which the first inlet pressure deviation amount dPL and the second differential pressure dP2 are associated with each other. Is remembered. The first inlet pressure deviation amount dPL is a difference between the above-described reference first inlet pressure PL and the first inlet pressure P1in detected by the first pressure sensor 6. The second differential pressure dP2 is a difference between the second inlet pressure that is the pressure of the fuel on the inlet side of the second filter 2 and the second outlet pressure that is the pressure of the fuel on the outlet side of the second filter 2. Here, in a state where the first filter 5 is not clogged, the second differential pressure dp2 and the reference first inlet pressure PL have a relationship as shown by a line L2 in FIG. 4B. That is, when the second filter 2 is clogged and it becomes difficult for the fuel to flow through the second filter 2, the first inlet pressure P1in on the downstream side of the second filter 2 decreases. Accordingly, as the second differential pressure dp2 increases, the reference first inlet pressure PL decreases and becomes smaller than the steady pressure Ps. However, in the actual case where clogging may occur in both the first filter 5 and the second filter 2, the first inlet pressure P1in changes as indicated by the line L3 in FIG. That is, the actual first inlet pressure P1in is smaller than the reference first inlet pressure PL (see line L1). This difference is the first inlet pressure deviation dPL, which is caused by the decrease in the first inlet pressure P1in as the second differential pressure dP2 increases as shown in FIG. 4B. . Therefore, the first inlet pressure deviation amount dPL in FIG. 4A corresponds to the amount of decrease in the reference first inlet pressure PL (see line L2) with respect to the steady pressure Ps in FIG. Have a specific relationship. The second table tabulates the relationship between the first inlet pressure deviation dPL and the second differential pressure dP2.

  The third storage unit 23 is a device that stores data, and stores threshold information. As shown in FIG. 5, the threshold information includes a threshold value (hereinafter, referred to as “clogging threshold value”) as a criterion for determining occurrence of clogging, and a threshold value (hereinafter, referred to as “error cancellation threshold value”) as a criterion for determining error cancellation. ) And is prepared for each of the first filter 5 and the second filter 2.

  Based on the detection signals detected by the first pressure sensor 6 and the second pressure sensor 7 and the data stored in the first to third storage units 21 to 23, the control unit 24 performs the first filter 5 and the second filter 5. The clogging of the filter 2 is determined. The control unit 24 includes a first differential pressure calculation unit 26, a deviation amount calculation unit 27, a second differential pressure acquisition unit 28, and a clogging determination unit 29.

  The first differential pressure calculator 26 calculates the first differential pressure dP1 from the first inlet pressure P1in detected by the first pressure sensor 6 and the first outlet pressure P1out detected by the second pressure sensor 7. The first differential pressure calculator 26 constitutes the first differential pressure detector 30 that detects the first differential pressure dP1 together with the second pressure sensor 7.

  The deviation amount calculation unit 27 refers to the first table stored in the first storage unit 21, and calculates the reference first inlet pressure PL corresponding to the first differential pressure dP1 detected by the first differential pressure detection unit 30. get. Then, the deviation amount calculation unit 27 calculates the first inlet pressure deviation amount dPL from the reference first inlet pressure PL and the first inlet pressure P1in.

  The second differential pressure acquisition unit 28 acquires the second differential pressure dP2 from the first inlet pressure deviation amount dPL with reference to the second table.

  The clogging determination unit 29 determines clogging of the first filter 5 from the first differential pressure dP1 and determines clogging of the second filter 2 from the second differential pressure dP2. Specifically, the clogging determination unit 29 determines that clogging has occurred in the first filter 5 when the first differential pressure dP1 is greater than the clogging threshold value a1, and the second differential pressure dP2 is clogged. If it is larger than the threshold value a2, it is determined that the second filter 2 is clogged. Further, the clogging determination unit 29 determines that the clogging of the first filter 5 has been eliminated when the first differential pressure dP1 becomes smaller than the error release threshold value b1 after determining that clogging has occurred. When the second differential pressure dP2 becomes smaller than the error release threshold b2, it is determined that the clogging of the second filter 2 has been eliminated.

  Note that the control unit 24 includes an arithmetic device such as a CPU and a storage device such as a RAM and a ROM. By the operation of these devices, the first differential pressure calculation unit 26, the deviation amount calculation unit 27, the first 2 functions as a differential pressure acquisition unit 28 and a clogging determination unit 29.

  The display unit 25 includes, for example, a panel that can display various screens, a lamp, and the like. The display unit 25 receives command signals from the control unit 24 and outputs various displays. If the clogging determination unit 29 determines that the first filter 5 is clogged, the display unit 25 outputs a warning display indicating that the first filter 5 is clogged. If the clogging determination unit 29 determines that the second filter 2 is clogged, the display unit 25 outputs a warning display indicating that the second filter 2 is clogged. To do. When the clogging determination unit 29 determines that the clogging of each filter has been eliminated, the display unit 25 stops outputting the corresponding warning display.

2. Control Flow Hereinafter, the filter clogging determination processing procedure will be described with reference to FIGS.

  First, as shown in FIG. 6, in steps S1 to S5, a first differential pressure dP1 and a second differential pressure dP2 are obtained.

  In step S1, the first inlet pressure P1in and the first outlet pressure P1out of the first filter 5 are detected. Here, the first pressure sensor 6 detects the first inlet pressure P1in. Further, the first outlet pressure P1out is detected by the second pressure sensor 7.

  In step S2, the first differential pressure dP1 is calculated. Here, the first differential pressure dP1 is calculated by the first differential pressure calculator 26 from the first inlet pressure P1in and the first outlet pressure P1out acquired in step S1.

  In step S3, the reference first inlet pressure PL is acquired. Here, the first table is referred to, and the reference first inlet pressure PL corresponding to the first differential pressure dP1 calculated in step S2 is acquired.

  In step S4, the first inlet pressure deviation amount dPL is calculated. Here, the first inlet pressure deviation amount dPL is calculated from the first inlet pressure P1in detected in step S1 and the reference first inlet pressure PL acquired in step S3 (PL-P1in = dPL).

  In step S5, the second differential pressure dP2 is calculated. Here, the second table is referred to, and the second differential pressure dP2 corresponding to the first inlet pressure deviation dPL calculated in step S4 is acquired.

  Next, as shown in FIG. 7, whether clogging has occurred or has been resolved is determined based on the first differential pressure dP1 and the second differential pressure dP2 obtained in steps S1 to S5. In FIG. 7, “F1” indicates the first filter 5, and “F2” indicates the second filter 2.

  In step S6, it is determined whether or not the first differential pressure dP1 is greater than the clogging threshold value a1 (first threshold value). When the first differential pressure dP1 is larger than the clogging threshold value a1, the process proceeds to step S7, and a warning display is output to the display unit 25.

  Next, in step S8, it is determined whether or not the first differential pressure dP1 is smaller than the error release threshold value b1. If the first differential pressure dP1 is smaller than the error release threshold value b1, the process proceeds to step S9, and the warning display is released.

  In the sixth step, when the first differential pressure dP1 is equal to or less than the clogging threshold value a1, the warning display is not output and the process proceeds to step S10. In step S8, if the first differential pressure dP1 is equal to or greater than the error release threshold b1, the warning display is not released and the process proceeds to step S10.

  In step S10, it is determined whether or not the second differential pressure dP2 is greater than the clogging threshold value a2 (second threshold value). When the second differential pressure dP2 is larger than the clogging threshold value a2, the process proceeds to step S11 and a warning display is output to the display unit 25.

  Next, in step S12, it is determined whether or not the second differential pressure dP2 is smaller than the error cancellation threshold value b2. If the second differential pressure dP2 is smaller than the error release threshold value b2, the process proceeds to step S13 and the warning display is released.

  In the tenth step, when the second differential pressure dP2 is equal to or less than the clogging threshold value a2, the warning display is not output and the process ends. If the second differential pressure dP2 is greater than or equal to the error release threshold value b2 in step S12, the warning display is not canceled and the process ends.

3. Features In the fuel supply system 100, the second differential pressure dP2 of the second filter 2 can be accurately calculated from the first inlet pressure P1in and the first outlet pressure P1out of the first filter 5. Accordingly, it is possible to determine whether the second filter 2 is clogged and released without adding a pressure sensor for detecting the second differential pressure dP2. Thereby, clogging of two filters can be determined, and an increase in the required number of sensors can be suppressed.

  In addition, since there is no need to provide a pressure sensor near the second filter 2, the clearance in the vehicle in which the fuel supply system 100 is provided can be increased. Thereby, the maintainability of the vehicle can be improved.

4). Other Embodiments In the above embodiment, the filter clogging determination device 8 is provided in the work vehicle, but may be provided in a server outside the vehicle. In this case, if the server manages a plurality of types of vehicles, different tables may be prepared for each vehicle type as shown in FIGS.

  In the above embodiment, the first table is used as the first relation information, but the first table is not limited to the table as long as it indicates the relation between the reference first inlet pressure PL and the first differential pressure dP1. The same applies to the second table as the second relation information.

  In the above embodiment, the first differential pressure detector 30 is configured by the second pressure sensor 7 and the first differential pressure calculator 26. However, the differential pressure sensor that directly detects the first differential pressure is the first differential sensor. It may be provided as a pressure detector.

  INDUSTRIAL APPLICABILITY The present invention has an effect of being able to determine clogging of two filters and suppressing an increase in the required number of sensors, and is useful as a filter clogging determination system and a filter clogging determination device.

Schematic which shows the structure of a fuel supply system. The control block diagram of a filter clogging determination apparatus. The figure which shows an example of the table as 1st relevant information and 2nd relevant information. The graph which shows the relationship between 1st differential pressure | voltage and a reference | standard 1st inlet pressure, and the relationship between 2nd differential pressure | voltage and a reference | standard 1st inlet pressure. The figure which shows an example of threshold value information. The flowchart which shows the determination process procedure of filter clogging. The flowchart which shows the determination process procedure of filter clogging.

Explanation of symbols

2 Second filter 2
5 First filter 5
6 1st pressure sensor (1st inlet pressure detection part)
21 First storage unit 22 Second storage unit 27 Deviation amount calculation unit 28 Second differential pressure acquisition unit 29 Clogging determination unit 30 First differential pressure detection unit

Claims (3)

A first filter provided in the fuel supply path;
A second filter provided upstream of the first filter in the fuel supply path;
A first inlet pressure detector that detects a first inlet pressure that is the pressure of fuel on the inlet side of the first filter;
A first differential pressure detection unit that detects a first differential pressure that is a pressure difference of fuel between an inlet side and an outlet side of the first filter;
A first storage unit that stores first relationship information indicating a relationship between the first differential pressure and a reference first inlet pressure indicating the first inlet pressure in a state where the second filter is not clogged;
The reference first inlet pressure corresponding to the first differential pressure detected by the first differential pressure detector is acquired with reference to the first relationship information, and the reference first inlet pressure and the first inlet are obtained. A deviation amount calculation unit that calculates a first inlet pressure deviation amount that is a difference from the first inlet pressure detected by the pressure detection unit;
A second storage unit that stores second relationship information indicating a relationship between the first inlet pressure deviation amount and a second differential pressure that is a fuel pressure difference between the inlet side and the outlet side of the second filter;
A second differential pressure acquisition unit that acquires the second differential pressure from the first inlet pressure deviation amount calculated by the deviation amount calculation unit with reference to the second relationship information;
A clogging determination unit for determining clogging of the first filter from the first differential pressure, and determining clogging of the second filter from the second differential pressure;
A filter clogging determination system comprising: When the first differential pressure is greater than a predetermined first threshold value, or when the second differential pressure is greater than a predetermined second threshold value, a display unit that outputs a predetermined warning display is further provided.
The filter clogging determination system according to claim 1. A first filter provided in a fuel supply path, a second filter provided upstream of the first filter in the fuel supply path, and a first inlet pressure that is a pressure of fuel on an inlet side of the first filter are detected. A fuel supply system comprising: a first inlet pressure detecting unit that detects a first differential pressure that is a pressure difference between the fuel at the inlet side and the outlet side of the first filter; A filter clogging determination device for determining clogging of the first filter and the second filter,
A first storage unit that stores first relationship information indicating a relationship between the first differential pressure and a reference first inlet pressure indicating the first inlet pressure in a state where the second filter is not clogged;
The reference first inlet pressure corresponding to the first differential pressure detected by the first differential pressure detector is acquired with reference to the first relationship information, and the reference first inlet pressure and the first inlet are obtained. A deviation amount calculation unit that calculates a first inlet pressure deviation amount that is a difference from the first inlet pressure detected by the pressure detection unit;
A second storage unit that stores second relationship information indicating a relationship between the first inlet pressure deviation amount and a second differential pressure that is a fuel pressure difference between the inlet side and the outlet side of the second filter;
A second differential pressure acquisition unit that acquires the second differential pressure from the first inlet pressure deviation amount with reference to the second relationship information;
A clogging determination unit for determining clogging of the first filter from the first differential pressure, and determining clogging of the second filter from the second differential pressure;
A filter clogging determination device comprising:

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