JP4534865B2 - Intake route monitoring device for fuel supply device - Google Patents

Description

  The present invention relates to a suction route monitoring device for a fuel supply device.

  2. Description of the Related Art Conventionally, an internal combustion engine is known in which a fuel filter is provided in the middle of a fuel pipe between a fuel pump and a fuel tank so as to remove foreign matters and impurities contained in the fuel.

  However, if the fuel used for the internal combustion engine contains a relatively large amount of foreign matter, impurities, etc., the fuel filter and the fuel pipe are likely to be clogged. When clogging occurs in the fuel filter and fuel piping, and the level increases, the amount of fuel supplied from the fuel pump to the internal combustion engine decreases, so the amount of fuel supplied to the engine also decreases, engine output decreases, exhaust gas There is a risk that the condition of the.

  An object of the present invention is to provide an intake path monitoring device for a fuel supply device capable of monitoring a state in an intake path between a fuel tank and a fuel pump, such as a fuel filter or clogging in a fuel pipe. .

In order to achieve the above object, a suction path monitoring device for a fuel supply apparatus according to claim 1 of the present invention includes a supply pump for pressurizing fuel supplied from a fuel tank via a fuel pipe, and a fuel pipe halfway. Provided between the fuel tank and the supply pump, the fuel in the fuel tank is sucked through the fuel pipe and supplied to the supply pump, and the fuel tank and the feed pump are in the middle of the fuel pipe. A first fuel filter provided in between, a second fuel filter provided in the middle of the fuel pipe and between the feed pump and the supply pump, and between the first fuel filter and the suction portion of the feed pump. In the fuel pipe between the first pressure detecting means for detecting the fuel pressure at a predetermined first detection location in the fuel pipe and the second fuel filter and the suction portion of the supply pump And a second pressure detection means for detecting the fuel pressure at a predetermined second detection location, and receives fuel pressure detection information from the first pressure detection means and receives a fuel pipe upstream of the first detection location. The fuel flow state in the inside and the first fuel filter is monitored, and the fuel pressure detection information from both the first pressure detection means and the second pressure detection means is received, and between the first detection place and the second detection place. The fuel flow condition in the fuel pipe and the second fuel filter
When the fuel pressure detected by the first pressure detecting means is determined to be lower than the first abnormality determination value of a predetermined, second the fuel pressure is predetermined to be detected by the second pressure detecting means Is determined to be greater than or equal to the abnormality determination value, it is determined that there is an abnormality in the fuel pipe or the first fuel filter upstream of the first detection location, while the first pressure detection means detects the abnormality. when the fuel pressure is determined to be lower than the first abnormality determination value given, the fuel pressure detected by the second pressure detecting means is determined to be lower than the second abnormality determination value Sometimes, both the fuel pipe or the second fuel filter between the first detection place and the second detection place, and both the fuel pipe or the first fuel filter upstream of the first detection place. Thereby determining that there is an abnormality in,
When it is determined that the fuel pressure detected by the first pressure detection means is greater than or equal to a predetermined first abnormality determination value, the fuel pressure detected by the second pressure detection means is a predetermined second When it is determined that the abnormality determination value is greater than or equal to the abnormality detection value, the fuel pipe or the second fuel filter between the first detection location and the second detection location, and the fuel piping upstream of the first detection location or the While it is determined that both of the first fuel filters are normal, the second pressure detection is performed when it is determined that the fuel pressure detected by the first pressure detection means is greater than or equal to the first abnormality determination value. when it is determined that the fuel pressure detected is lower than the second abnormality determination value by the means, the fuel pipe or the second fuel filter between said second detection location and said first detection location Is characterized in that it comprises an abnormality determination means determines that there is an abnormality.

According to this configuration, the suction path monitoring device of the fuel supply device detects the fuel pressure in the fuel pipe between the first fuel filter and the suction portion of the feed pump by the first pressure detection means, and the second fuel filter and the fuel pressure in the fuel in the pipe between the inlet portion of the supply pump is detected by the second pressure detecting means, and receives the detection information of these fuel pressure monitors fuel flow condition of the fuel pipe middle. For this reason , the intake path of the fuel supply device can be managed, and as a result , the reliability of the fuel supply device is improved.

According to a second aspect of the present invention, in the intake path monitoring device of the fuel supply device according to the first aspect , the history of the fuel pressure detected by the first pressure detecting means and the second pressure detecting means Storage means for storing a history of fuel pressure is provided. According to this configuration, each history of the fuel pressure detected by the first and second pressure detection means is stored in the storage means. As a result, it is possible to grasp the change with time of the intake path of the fuel supply device, and management becomes easy.

The invention described in claim 3 of the present invention, in the suction route monitoring device of a fuel supply device according to claim 2, memorize means is characterized in that for storing the abnormality detection history by the abnormality judgment means.
According to this structure, the suction path monitoring apparatus as claimed in claim 2, since so as to store a history of the detected abnormality detected by abnormality determination means storage means, for example, the first detection location of the fuel pressure It is possible to determine an abnormal state of the suction path such as clogging in the fuel pipe or the first fuel filter on the upstream side.

According to a fourth aspect of the present invention, there is provided the fuel supply means according to any one of the first to third aspects, wherein the fuel viscosity means for determining the viscosity of the fuel in the fuel pipe is provided. The abnormality determining means includes a correcting means for correcting the fuel pressure detected by the first and second pressure detecting means or the first and second abnormality determining values based on the fuel viscosity.

  In general, it is known that the fuel viscosity varies depending on the surrounding environment, its type (oil type), and region. The fuel pressure in the fuel pipe is affected by the fuel viscosity, and the fuel pressure may change if the fuel viscosity is different. According to this configuration, the viscosity of the fuel in the fuel pipe is obtained by the fuel viscosity means, and the correction means provided in the abnormality determination means corrects the fuel pressure or the abnormality determination value based on the obtained fuel viscosity. Therefore, the accuracy of abnormality determination is improved. The means for obtaining the fuel viscosity may be obtained from another physical quantity capable of calculating the fuel viscosity, or may be obtained by a sensor or the like that can detect the fuel viscosity.

According to a fifth aspect of the present invention, in the intake path monitoring device for the fuel supply device according to the fourth aspect , the fuel supply device further comprises a temperature detecting means for detecting the fuel temperature in the fuel pipe, and the fuel viscosity means The fuel viscosity is obtained based on In general, it is known that the fuel viscosity and the fuel temperature have a correlation. According to this configuration, the fuel viscosity can be easily obtained from a map, an arithmetic expression, or the like.
The invention described in claim 6 of the present invention, in the suction route monitoring device of a fuel supply device according to any one of claims 1 to 5, the first detection location is an intake section of the feed pump The second detection place is a suction part of a supply pump. According to this configuration, the first detection location of the fuel pressure is used as the suction portion of the feed pump and the second detection location of the fuel pressure is used as the suction portion of the supply pump. Therefore, the monitoring section of the suction path can be made longer.

  A plurality of embodiments in which a suction route monitoring device for a fuel supply device of the present invention is applied to a common rail fuel supply device mounted on a diesel engine will be described with reference to the drawings.

(First embodiment)
FIG. 1 is a diagram showing an overall configuration of a common rail fuel supply apparatus (hereinafter referred to as a fuel supply apparatus). FIG. 2 is a diagram showing a change in fuel pressure in the fuel pipe of the fuel supply apparatus of the present embodiment. FIG. 3 is a flowchart showing the operation of the intake path monitoring device of the fuel supply apparatus of this embodiment.

  The fuel supply device 1 is a device that supplies fuel to each cylinder of a 6-cylinder diesel engine mounted on a vehicle such as an automobile. The fuel supply apparatus 1 mainly includes a fuel tank 10, a first fuel filter 130, a feed pump 20, a second fuel filter 140, a supply pump 30, a metering valve 32, a common rail 40, an injector 50, and an electronic control unit ( Hereinafter, an ECU) 90 is provided.

  The feed pump 20 is driven by a diesel engine (not shown), sucks the fuel stored in the fuel tank 10, and supplies the fuel to the supply pump 30. Between the fuel tank 10 and the feed pump inlet 21 of the feed pump 20, a first fuel pipe 60, a first fuel filter 130, and a second fuel pipe 61 are provided from the fuel tank 10 side. A first pressure sensor 110 is attached in the middle of the second fuel pipe 61. The first pressure sensor 110 detects the fuel pressure P <b> 1 in the fuel pipe 61.

  The supply pump 30 is driven by a diesel engine (not shown), further pressurizes the fuel supplied from the feed pump 20, and supplies the pressurized high-pressure fuel to the common rail 40 via the high-pressure fuel pipe 80. A third fuel pipe 62, a second fuel filter 140, and a fourth fuel pipe 63 are provided from the feed pump 20 side between the feed pump discharge port 22 and the supply pump suction port 31 of the supply pump 30. A second pressure sensor 120 is attached in the middle of the fourth fuel pipe 63. The second pressure sensor 120 detects the fuel pressure P <b> 2 in the fuel pipe 63.

  The supply pump 30 is provided with a metering valve 32. The metering valve 32 adjusts the amount of high-pressure fuel supplied to the common rail 40 and adjusts the fuel pressure in the common rail 40. The supply pump 30 is also provided with a leak port so that the fuel temperature inside the pump 30 does not become high. The leaked fuel from the supply pump 30 is returned from the leak port to the fuel tank 10 through the return pipe 71 and the return pipe 70.

  The first and second fuel filters 130 and 140 remove foreign matters and impurities contained in the fuel sucked from the fuel tank 10 or the fuel sent from the feed pump 20. The fuel path from the supply pump 30 to the fuel tank 10 corresponds to the suction path described in the claims.

  The common rail 40 accumulates high-pressure fuel necessary for the fuel pressure injected from the injector 50 to each cylinder. The common rail 40 is provided with a return pipe 72 that leads to return pipes 70, 71, 73. A pressure limiter 41 is provided between the return pipe 72 and the common rail 40. When the fuel pressure in the common rail 40 exceeds the limit set pressure, the pressure limiter 41 opens to release the fuel in the common rail 40 and lower the fuel pressure.

  An injector 50 mounted in each cylinder of a diesel engine is configured by a nozzle portion 51 having a nozzle needle that opens and closes an injection hole, and an actuator 52 such as an electromagnetic valve that drives the nozzle needle in a valve opening direction. . The injector 50 is connected to the downstream ends of a plurality of high-pressure fuel pipes 81 branched from the common rail 40. A return pipe 73 is connected to the injector 50, and fuel (surplus fuel) that has not been used for fuel injection into the cylinder is recirculated from the return pipe 73 to the fuel tank 10 via the return pipe 70.

  The ECU 90 is composed of a digital computer and includes a ROM 91, a RAM 92, a CPU 93, an input port 95, and an output port 96 that are connected to each other by a bidirectional bus 94.

  The output signal of the accelerator opening sensor 100 and the output signals of the first and second pressure sensors 110 and 120 are input to the input port 95 via the corresponding A / D converter 97. Further, the input port 95 is connected to a rotation speed sensor 101 that generates an output pulse every time a crankshaft of a diesel engine (not shown) rotates, for example, by 30 °, and an output signal of the rotation speed sensor 101 is input to the input port 95. The

  The output port 96 is connected to the actuator 52 and the metering valve 32, which are controlled objects, via a plurality of corresponding drive circuits 98. A control signal from the output port 96 is sent to each control object via these drive circuits 98. Further, the alarm device 102 is connected to the output port 96 via a corresponding drive circuit 98.

  This alarm device 102 informs the driver of an abnormality such as clogging in the first to fourth fuel pipes 60, 61, 62, 63 and the first and second fuel filters 130, 140. For example, a warning lamp or a warning buzzer is used.

  Next, the intake route monitoring device of the fuel supply device of the present invention will be described in detail. If an abnormality such as clogging occurs in the first to fourth fuel pipes 60, 61, 62, 63 upstream of the supply pump 30 and the first and second fuel filters 130, 140, and the degree of clogging increases, the diesel engine Etc. The degree of clogging or clogging of the fuel pipes 60, 61, 62, 63 and the fuel filters 130, 140 can be determined from changes in the fuel pressures P1, P2 of the second and fourth fuel pipes 61, 63 ( (See FIG. 2).

  FIG. 2 is a diagram showing changes in the fuel pressure in the second and fourth fuel pipes 61 and 63, and FIG. 2 (a) shows changes in the fuel pressure P1 in the second fuel pipe 61, and FIG. b) shows a change in the fuel pressure P <b> 2 in the fourth fuel pipe 63. ATM indicates atmospheric pressure. The limit pressure α and the limit pressure β are pressures that may adversely affect diesel engines and the like when the fuel pressure in the second and fourth fuel pipes 61 and 63 is lower than the respective pressures α and β. . These pressures α and β are experimentally obtained, and are pressures when, for example, there is a possibility that bubbles are generated in the fuel pipe or the output of the diesel engine or the state of exhaust gas is deteriorated.

  As shown in FIG. 2A, for example, when clogging occurs upstream of the position of the first pressure sensor 110 attached to the second fuel pipe 61 and the degree of clogging increases with time, the fuel The pressure P1 decreases with time. When the fuel pressure P1 further decreases and reaches time t1, the fuel pressure P1 reaches a limit pressure α lower than ATM. At this time, it can be determined that clogging has occurred upstream of the attachment position of the first pressure sensor 110 (section A shown in FIG. 1). In addition, the attachment position of the 1st pressure sensor 110 is corresponded to the detection place as described in a claim.

  As shown in FIG. 2B, for example, when clogging occurs upstream of the position of the second pressure sensor 120 attached to the fourth fuel pipe 63 and the degree of clogging increases with time, the fuel The pressure P2 decreases with time. When the fuel pressure P2 further decreases and time t2 is reached, the fuel pressure P2 reaches the limit pressure β. At this time, it can be determined that clogging has occurred upstream of the attachment position of the second pressure sensor 130 (section A and section B shown in FIG. 1). Further, in consideration of changes in both the fuel pressures P1 and P2, it can also be determined that clogging occurs upstream from the second pressure sensor 120 and downstream from the first pressure sensor 110 (FIG. B section shown in 1). The mounting position of the second pressure sensor 120 corresponds to the detection location described in claim 1.

  Next, the control flow of this embodiment will be described. In the present embodiment, a control flow for detecting an abnormal state will be described in particular, among the monitoring of the intake path of the fuel supply device. In step S10, the ECU 90 determines whether or not the diesel engine is in an idle operation state. This determination is performed based on output signals from the accelerator opening sensor 100 and the rotation speed sensor 101, for example. The ECU 90 advances the process to step S20 if the determination result is YES, and repeats the process of step S10 if the determination result is NO.

  In step S20, the ECU 90 detects the fuel pressures P1 and P2, and stores the detection results in the RAM 92. When the ECU 90 stores the fuel pressures P1 and P2 in the RAM 92, the ECU 90 also stores the detection times of the fuel pressures P1 and P2. In step S30, the ECU 90 determines whether or not the fuel pressure P1 is lower than the limit pressure α. If a determination result is YES, ECU90 will advance a process to step S50. At this time, it is determined that there is an abnormality such as clogging in the A section. If the determination result is NO, the ECU 90 proceeds with the process to step S40 (step S40 will be described later).

  In step S50, the ECU 90 determines whether or not the fuel pressure P2 is lower than the limit pressure β. If the determination result is YES, the ECU 90 proceeds with the process to step S90, and if there is an abnormality such as clogging in both the A section and the B section in step S90, the ECU 90 stores the abnormality in the RAM 92 and ends this control flow. . If the determination result is NO, the ECU 90 advances the process to step S80, and if there is an abnormality such as clogging in the section A in step S80, stores it in the RAM 92 and ends this control flow.

  On the other hand, in step S40, it is determined whether or not the fuel pressure P2 is lower than the limit pressure β. If a determination result is YES, ECU90 will advance a process to step S70, will memorize | store in RAM92 if there exists abnormality, such as clogging, in B area, and will complete | finish this control flow. If the determination result is NO, the ECU 90 advances the process to step S60, stores in the RAM 92 that both the A section and the B section are normal, and ends this control flow.

  By executing this control flow, the ECU 90 can determine an abnormal state such as clogging occurring in the fuel pipes 60, 61, 62, 63 or the fuel filters 130, 140 upstream of the supply pump 30. Steps S30 to S90 of the control flow shown in FIG. 3 correspond to the abnormality determination means described in claim 2. The RAM 92 corresponds to a storage unit according to claims 1 and 2. When the ECU 90 stores the abnormal state determined in steps S30 to S90 in the RAM 92, the ECU 90 also stores the time when the abnormal state occurs together with the abnormal state.

  After the end of this control flow, the ECU 90 generates a control signal corresponding to the state determined in step S70, step S80, and step S90 by another control flow (not shown), and signals the control signal according to, for example, an alarm Output to the device 102. The alarm device 102 issues an alarm according to the control signal output from the ECU 90.

  The ECU 90 executes the control flow to monitor the state of the fuel flow in the intake path based on the fuel pressures P1 and P2 in the intake path of the fuel supply apparatus 1, so that the intake of the fuel supply apparatus 1 The route can be managed, and the reliability of the fuel supply device 1 is improved.

  Further, the ECU 90 stores the history of the fuel pressures P1 and P2 detected by the first and second pressure sensors 110 and 120 in the RAM 92, which is a storage unit, by executing this control flow. The change with time of the inhalation route of the apparatus 1 can be grasped. Further, these fuel pressures P1 and P2 can be taken out from the RAM 92 and analyzed. Thereby, management of the fuel supply apparatus 1 becomes easy.

  In the present embodiment, the attachment positions of the first and second pressure sensors 110 and 120 are attached in the vicinity of the outlet portions of the first and second fuel filters 130 and 140. If the mounting positions of the first and second pressure sensors 110 and 120 are set near the feed pump suction port 21 and the supply pump suction port 31, respectively, the monitoring section can be lengthened.

(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIG. FIG. 4 is a diagram showing a change in the fuel pressure P1 detected by the first pressure sensor. In addition, the same code | symbol is attached | subjected to the same function thing and the same process as 1st Embodiment. Here, only the feature points different from the first embodiment will be described.

  As shown in FIG. 4, when the ECU 90 detects the fuel pressure P1 in step S20, the ECU 90 performs processing for storing the fuel pressure P1 and information on the time when the fuel pressure P1 is detected in the RAM 92 as a history of the fuel pressure P1. Yes. FIG. 4 shows only the fuel pressure P1. Of course, for the fuel pressure P2, the history of the fuel pressure P2 may be stored in the RAM 92 similarly. Hereinafter, an example of the fuel pressure P1 detected by the first pressure sensor 110 will be described.

  If the history of the fuel pressure P1 is stored in the RAM 92, a mechanic or the like analyzes the history of the fuel pressure P1, so that, for example, the replacement time, the replacement interval, or the replaced fuel filter 130 of the fuel filter 130 is analyzed. Quality (genuine product, poor product) etc. can be discriminated.

  As shown in FIG. 4, the fuel pressure P1 suddenly increases at times t1 and t2. Thereby, it can be determined that the fuel filter 130 has been replaced. Further, by comparing ΔP1 at time t1 and ΔP2 at time t2, the quality and the like of the replaced fuel filter 130 can be determined. In FIG. 4, ΔP2 at time t2 is smaller than ΔP1 at time t1 when the fuel filter 130 is replaced. This is an element for determining that the fuel filter 130 replaced at time t2 is a poor product. Further, the quality of the fuel filter 130 can be determined by examining the time interval when the fuel pressure P1 falls below the limit pressure α after the fuel filter 130 is replaced.

(Third embodiment)
Next, a third embodiment of the present invention will be described with reference to FIGS. FIG. 5 is a flowchart showing the operation of the intake path monitoring device of the fuel supply apparatus of this embodiment. FIG. 6 is a graph showing the relationship between fuel temperature and fuel viscosity.

  In step S110, the ECU 90 determines whether or not the diesel engine is in an idle operation state. This determination is performed based on output signals from the accelerator opening sensor 100 and the rotation speed sensor 101, for example. If the determination result is YES, ECU 90 advances the process to step S120, and if NO, repeats the process of step S110.

  In step S120, the ECU 90 detects the fuel pressures P1, P2 and the fuel temperature TMP, and stores the detection results in the RAM 92. When the ECU 90 stores the fuel pressures P1 and P2 and the fuel temperature TMP in the RAM 92, the ECU 90 also stores the detection times of the fuel pressures P1 and P2 and the fuel concentration TMP. As the fuel temperature TMP, the temperature in the fuel tank 10 may be detected, or the temperature of the fuel in the second and fourth fuel pipes 61 and 63 may be detected.

  In step S130, the ECU 90 calculates the fuel viscosity V based on the fuel temperature TMP. The fuel temperature TMP and the fuel viscosity V have a relationship as shown in FIG. 6 and are calculated by a map or an arithmetic expression. When the fuel temperature TMP is detected at a plurality of points (second and fourth fuel pipes 61 and 63), the fuel viscosity V corresponding to each fuel temperature TMP is calculated. The fuel viscosity V may be obtained by a map or an arithmetic expression as in the present embodiment, but the fuel viscosity V may be directly detected by a sensor or the like that detects the fuel viscosity.

  In step S140, the ECU 90 corrects the values of the limit pressures α and β based on the fuel viscosity V. Generally, it is known that when the fuel viscosity V changes, the pressure of the fuel flowing through the fuel pipes 60, 61, 62, 63 and the fuel filters 130, 140 also changes. Correcting the limit pressures α and β based on the fuel viscosity V can prevent erroneous determination. When a plurality of fuel viscosities V are calculated, the limit pressures α and β are corrected with the corresponding fuel viscosities V. Thereby, the determination accuracy of the abnormal state is further improved. The values corrected by the fuel viscosity V may be fuel pressures P1 and P2.

  In step S150, the ECU 90 determines whether or not the fuel pressure P1 is lower than the limit pressure α. If a determination result is YES, ECU90 will advance a process to step S170. At this time, it is determined that there is an abnormality such as clogging in the A section. If the determination result is NO, the ECU 90 advances the process to step S160 (step S160 will be described later).

  In step S170, the ECU 90 determines whether or not the fuel pressure P2 is lower than the limit pressure β. If the determination result is YES, the ECU 90 advances the process to step S210, and if there is an abnormality such as clogging in both the A section and the B section in step S210, stores the abnormality in the RAM 92 and ends this control flow. . If the determination result is NO, the ECU 90 advances the process to step S200, and if there is an abnormality such as clogging in the section A in step S200, stores it in the RAM 92, and ends this control flow.

  On the other hand, in step S160, it is determined whether or not the fuel pressure P2 is lower than the limit pressure β. If the determination result is YES, the ECU 90 advances the process to step S190, stores in the RAM 92 if there is an abnormality such as clogging in the B section, and ends this control flow. If the determination result is NO, the ECU 90 advances the process to step S180, stores in the RAM 92 that both the A section and the B section are normal, and ends this control flow. When the ECU 90 stores the abnormal state determined in steps S150 to S210 in the RAM 92, the ECU 90 also stores the time when the abnormal state occurs together with the abnormal state.

  After the end of this control flow, the ECU 90 generates a control signal corresponding to the state determined in step S190, step S200, and step S210 by another control flow (not shown), and signals the control signal according to, for example, an alarm Output to the device 102. The alarm device 102 issues an alarm according to the control signal output from the ECU 90.

  In the present embodiment, the fuel viscosity V is calculated using the relationship between the fuel temperature TMP and the fuel viscosity V, and the limit pressures α and β are corrected. It is known that the fuel viscosity V varies depending on the region where the fuel is used. You may make it correct | amend limit pressure (alpha) and (beta) using the fuel viscosity V according to the fuel of the area | region which uses a diesel engine.

(Other embodiments)
In the first to third embodiments, the example in which the intake path monitoring device of the fuel supply apparatus is applied to a diesel engine has been described. However, the intake path monitoring device is applied to a gasoline internal combustion engine that is a spark ignition type. The same effect can be obtained. Further, the suction route monitoring device of the present invention may be applied to a fuel supply device in which the feed pump 20 and the supply pump 30 are integrated.

It is the figure which showed the whole structure of the common rail type fuel supply apparatus. It is a figure which shows the change of the fuel pressure in the fuel piping of the fuel supply apparatus of 1st Embodiment. It is a flowchart which shows operation | movement of the suction route monitoring apparatus of the fuel supply apparatus of 1st Embodiment. It is a figure which shows the change of the fuel pressure of the suction route of the fuel supply apparatus of 2nd Embodiment. It is a flowchart which shows operation | movement of the suction route monitoring apparatus of the fuel supply apparatus of 3rd Embodiment. It is a figure which shows the relationship between fuel temperature and fuel viscosity.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Fuel supply apparatus 10 Fuel tank 20 Feed pump 21 Feed pump inlet 22 Feed pump outlet 30 Supply pump 31 Supply pump inlet 32 Metering valve 40 Common rail 41 Pressure limiter 50 Injector 51 Nozzle part 52 Actuator 60 1st fuel piping 61 Second fuel pipe 62 Third fuel pipe 63 Fourth fuel pipe 90 Electronic control unit (ECU)
92 RAM (storage means)
102 alarm device 110 first pressure sensor (pressure detection means)
120 Second pressure sensor (pressure detection means)
130 1st fuel filter 140 2nd fuel filter

Claims (6)

A supply pump for pressurizing the fuel supplied from the fuel tank via the fuel pipe;
A feed pump that is provided between the fuel tank and the supply pump in the middle of the fuel pipe, sucks the fuel in the fuel tank through the fuel pipe, and supplies the fuel to the supply pump;
A first fuel filter provided in the middle of the fuel pipe and between the fuel tank and the feed pump;
A second fuel filter provided in the middle of the fuel pipe and between the feed pump and the supply pump;
First pressure detecting means for detecting a fuel pressure at a predetermined first detection location in the fuel pipe between the first fuel filter and the suction portion of the feed pump;
A second pressure detecting means for detecting a fuel pressure at a predetermined second detection location in the fuel pipe between the second fuel filter and the suction portion of the supply pump;
Receiving fuel pressure detection information from the first pressure detecting means, monitoring the fuel flow state in the fuel pipe upstream of the first detection location and in the first fuel filter;
Upon receiving fuel pressure detection information from both the first pressure detection means and the second pressure detection means, the fuel pipe and the second fuel filter between the first detection place and the second detection place Monitoring the fuel flow condition in the
When the fuel pressure detected by the first pressure detecting means is determined to be lower than the first abnormality determination value of a predetermined, second the fuel pressure is predetermined to be detected by the second pressure detecting means Is determined to be greater than or equal to the abnormality determination value, it is determined that there is an abnormality in the fuel pipe or the first fuel filter upstream of the first detection location, while the first pressure detection means detects the abnormality. when the fuel pressure is determined to be lower than the first abnormality determination value given, the fuel pressure detected by the second pressure detecting means is determined to be lower than the second abnormality determination value Sometimes, both the fuel pipe or the second fuel filter between the first detection place and the second detection place, and both the fuel pipe or the first fuel filter upstream of the first detection place. Thereby determining that there is an abnormality in,
When it is determined that the fuel pressure detected by the first pressure detection means is greater than or equal to a predetermined first abnormality determination value, the fuel pressure detected by the second pressure detection means is a predetermined second When it is determined that the abnormality determination value is greater than or equal to the abnormality detection value, the fuel pipe or the second fuel filter between the first detection location and the second detection location, and the fuel piping upstream of the first detection location or the While it is determined that both of the first fuel filters are normal, the second pressure detection is performed when it is determined that the fuel pressure detected by the first pressure detection means is greater than or equal to the first abnormality determination value. when it is determined that the fuel pressure detected is lower than the second abnormality determination value by the means, the fuel pipe or the second fuel filter between said second detection location and said first detection location Inhalation route monitoring device of a fuel supply system, characterized in that it comprises an abnormality determination means determines that there is an abnormality.   2. The fuel according to claim 1, further comprising storage means for storing the history of the fuel pressure detected by the first pressure detection means and the history of the fuel pressure detected by the second pressure detection means. Inhalation route monitoring device of supply device.   The intake path monitoring device for a fuel supply apparatus according to claim 2, wherein the storage means stores a history of abnormality detection by the abnormality determination means. A fuel viscosity means for determining the viscosity of the fuel in the fuel pipe;
The abnormality determination means includes correction means for correcting the fuel pressure detected by the first and second pressure detection means or the first and second abnormality determination values based on the fuel viscosity. The intake path monitoring device for a fuel supply device according to any one of claims 1 to 3. Temperature detecting means for detecting the fuel temperature in the fuel pipe;
The intake path monitoring device for a fuel supply apparatus according to claim 4, wherein the fuel viscosity means obtains the fuel viscosity based on the fuel temperature. The first detection location is the suction portion of the feed pump;
The intake path monitoring device for a fuel supply device according to any one of claims 1 to 5, wherein the second detection location is the suction portion of the supply pump.

Images