JP2015052297A - Shovel and management device for the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect supply of inferior fuel at an early stage.SOLUTION: A shovel according to an embodiment of the invention includes hydraulic actuators 7-9 for driving work attachments 4-6, a main pump 14 for supplying pressure oil to the hydraulic actuators 7-9, a control section 30 for controlling the hydraulic actuators 7-9, an internal combustion engine 11 for rotationally driving the main pump 14, internal combustion engine system abnormality detecting sections 11a-11d for detecting abnormality of the engine 11, a filter 50b for collecting PM in exhaust gas provided in an exhaust passage of the engine 11, and a differential pressure sensor 50c attached to the filter 50b. The control section 30 includes a fuel quality determination section 50b for determining quality of fuel based on a clogging condition of the filter 50b determined on the basis of output of the differential pressure sensor 50c and output of an engine system abnormality detection section 35a.

Description

  The present invention relates to an excavator equipped with a filter that collects particulate matter (hereinafter referred to as “PM”) in exhaust gas, and an excavator management device.

  Patent Document 1 discloses a DPF forced regeneration circuit that incinerates and removes PM deposited on a diesel particulate filter (hereinafter referred to as “DPF”).

  This DPF forced regeneration circuit supplies fuel to the oxidation catalyst in the DPF through the exhaust pipe of the engine by performing post-injection (post-injection) of the fuel immediately after the explosion process of the engine. Then, the temperature of the oxidation catalyst and thus the DPF is raised by the heat generated by the combustion (oxidation reaction) of the fuel, and the PM deposited on the DPF is heated and burned. In this manner, the DPF forced regeneration circuit automatically and periodically regenerates the DPF by periodically burning and removing the PM deposited on the DPF.

JP 2010-261340 A

  However, when inferior fuel is supplied to an excavator engine, a larger amount of sulfate, ash, etc. is accumulated in the DPF than high quality fuel. Since these sulfates, ash, and the like have a high melting point, even if the regeneration process of the DPF is automatically executed, it is not burned and removed, and the DPF is blocked. Furthermore, due to the influence of bad fuel, it causes adverse effects such as excessive discharge of black smoke and a decrease in compression pressure of the engine.

  However, when the load increases rapidly due to a sudden lever operation by the operator despite the use of good quality fuel, black smoke is used in the same way as when using poor fuel. Excessive emissions will occur. Also, when an abnormality occurs in the hydraulic system, the load increases rapidly, and black smoke may be excessively discharged.

  Furthermore, even when an abnormality occurs in a detection system such as a pressure sensor, or when the atmospheric pressure is low, the compression pressure of the engine is reduced despite the use of good quality fuel.

  In this way, the adverse effects caused by the excavator (excessive black smoke discharge, decrease in engine compression pressure, etc.) are similar to the abnormalities of the engine system and hydraulic system, so the cause of the adverse effects is poor. Even when the fuel is used, a complicated confirmation work is required before the cause is specified.

  Therefore, it is desired to detect at an early stage that poor fuel has been supplied.

  An excavator according to an embodiment of the present invention includes a lower traveling body, an upper revolving body that is rotatably mounted on the lower traveling body, a work attachment that is mounted on the upper revolving body, and a plurality of driving the work attachments. A main pump for supplying pressure oil to the plurality of hydraulic actuators mounted on the upper swing body, a control unit for controlling the plurality of hydraulic actuators mounted on the upper swing body, An internal combustion engine that rotationally drives the main pump mounted on the upper swing body, an internal combustion engine system abnormality detection unit that detects an abnormality of the internal combustion engine, and an exhaust gas of the internal combustion engine that is mounted on the upper swing body An excavator having a filter provided in a passage for collecting particulate matter in exhaust gas, and a pressure sensor attached to the filter. The engine is controlled to maintain a predetermined rotation speed, and the control unit is based on the degree of clogging of the filter determined based on the output of the pressure sensor and the output of the internal combustion engine system abnormality detection unit. A fuel quality determination unit that determines quality of the fuel is provided.

  An excavator management device according to an embodiment of the present invention includes a lower traveling body, an upper swing body that is pivotably mounted on the lower traveling body, a work attachment that is mounted on the upper swing body, and the work Controls a plurality of hydraulic actuators for driving attachments, a main pump for supplying pressure oil to the plurality of hydraulic actuators mounted on the upper swing body, and the plurality of hydraulic actuators mounted on the upper swing body An internal combustion engine which is mounted on the upper swing body and is driven to rotate the main pump so as to maintain a predetermined rotational speed, and an internal combustion engine system abnormality detection which detects abnormality of the internal combustion engine Part, a filter mounted on the upper revolving structure, provided in an exhaust passage of the internal combustion engine, for collecting particulate matter in the exhaust, and attached to the filter An excavator management device comprising: a pressure sensor, wherein the filter is clogged based on the output of the pressure sensor, and the determination result of the internal combustion engine system abnormality detection unit is transmitted from the excavator. A determination processing unit that determines whether the fuel is good or bad; and a display unit that displays a determination result by the determination processing unit.

  By the above-mentioned means, an excavator capable of detecting at an early stage that poor fuel has been supplied is provided.

It is a side view of the shovel which concerns on the Example of this invention. It is a block diagram which shows the structural example of the drive system of the shovel of FIG. It is an example of the flowchart which shows the flow of a fuel quality determination process. It is another example of the flowchart which shows the flow of a fuel quality determination process. It is the schematic which shows the relationship between the operating time of a shovel, and DPF differential pressure. It is explanatory drawing of a 1st determination condition. It is explanatory drawing of a 2nd determination condition. It is explanatory drawing of 3rd determination conditions. It is explanatory drawing of 4th determination conditions. It is explanatory drawing of 5th determination conditions.

  First, an excavator according to an embodiment of the present invention will be described with reference to FIG. FIG. 1 is a side view of the excavator according to the embodiment. An upper swing body 3 is mounted on a lower traveling body 1 of the shovel shown in FIG. A work attachment is attached to the upper swing body 3. The work attachment includes, for example, a boom 4, an arm 5, and a bucket 6. Specifically, the boom 4 is attached to the upper swing body 3, the arm 5 is attached to the tip of the boom 4, and the bucket 6 is attached to the tip of the arm 5. The boom 4, the arm 5, and the bucket 6 are hydraulically driven by a boom cylinder 7, an arm cylinder 8, and a bucket cylinder 9, respectively. The upper swing body 3 is provided with a cabin 10 and is mounted with a power source such as an engine 11.

  FIG. 2 is a block diagram showing a configuration example of a drive system mounted on the excavator of FIG. 1, and a mechanical power system, a high-pressure hydraulic line, a pilot line, and an electric control system are respectively represented by a double line, a solid line, a broken line, And it shows with a dashed-dotted line.

  The drive system of the shovel mainly includes an engine 11, a regulator 13, a main pump 14, a control valve 17, operating devices 26a and 26b, a gate lock lever 27, a controller 30, an engine controller 35, and an exhaust system 50.

  The engine 11 is a drive source of the excavator, for example, a diesel engine as an internal combustion engine. The engine 11 is controlled by the engine controller 35 so as to maintain a predetermined rotational speed. The output shaft of the engine 11 is connected to the input shaft of the main pump 14. In this embodiment, the engine 11 is provided with a rotation speed sensor 11a, a boost pressure sensor 11b, an atmospheric pressure sensor 11c, and a water temperature sensor 11d.

  The rotation speed sensor 11 a is a sensor that detects the rotation speed of the engine 11 and outputs the detected value to the engine controller 35.

  The boost pressure sensor 11 b is a sensor that detects the boost pressure of the engine 11 and outputs the detected value to the engine controller 35.

  The atmospheric pressure sensor 11 c is a sensor that detects the atmospheric pressure around the engine 11, and outputs the detected value to the engine controller 35.

  The water temperature sensor 11 d is a sensor that detects the temperature of the cooling water of the engine 11, and outputs the detected value to the engine controller 35.

  The regulator 13 is a device for controlling the discharge amount of the main pump 14. For example, the regulator 13 adjusts the tilt angle of the swash plate of the main pump 14 according to the discharge pressure of the main pump 14 or a control signal from the controller 30. By doing so, the discharge amount of the main pump 14 is controlled.

  The main pump 14 is a device for supplying hydraulic oil to the control valve 17 through a high-pressure hydraulic line, and is, for example, a swash plate type variable displacement hydraulic pump.

  The discharge pressure sensor 14 a is a pressure sensor that detects the discharge pressure of the main pump 14. In the present embodiment, the discharge pressure sensor 14 a detects the pressure of the hydraulic oil in the high-pressure hydraulic line on the downstream side of the main pump 14 and outputs the detected value to the controller 30.

  The control valve 17 is a hydraulic control device that controls a hydraulic system in the excavator. The control valve 17 is, for example, one or more of a boom cylinder 7, an arm cylinder 8, a bucket cylinder 9, a traveling hydraulic motor (not shown), and a turning hydraulic motor (not shown). On the other hand, hydraulic oil discharged from the main pump 14 is selectively supplied. In FIG. 2, the control valve 17 includes a boom switching valve 17 a that controls supply / discharge of hydraulic oil to / from the boom cylinder 7, an arm switching valve 17 b that controls supply / discharge of hydraulic oil to / from the arm cylinder 8, and the bucket cylinder 9. Including a bucket switching valve 17c for controlling the supply and discharge of hydraulic oil to and from the bucket. In FIG. 2, for the sake of clarity, illustration of switching valves corresponding to the traveling hydraulic motor and the turning hydraulic motor is omitted. Hereinafter, the boom cylinder 7, the arm cylinder 8, the bucket cylinder 9, the traveling hydraulic motor, and the turning hydraulic motor are collectively referred to as “hydraulic actuators”.

  Further, on the downstream side of the control valve 17, a negative control throttle 18 for negative control (a method for controlling the discharge amount of the main pump 14, hereinafter referred to as “negative control”) is installed. The negative control pressure, which is the pressure of the hydraulic oil upstream of the negative control throttle 18, is introduced into the regulator 13 through the negative control pilot line 19. With this configuration, the discharge amount of the main pump 14 increases as the negative control pressure decreases, and is controlled so that the operation amount of the hydraulic actuator increases. Further, the discharge amount of the main pump 14 is limited to a predetermined amount (for example, a minimum flow rate) when the negative control pressure becomes equal to or higher than the predetermined pressure, that is, when any hydraulic actuator is not operated. The valve 20a is a relief valve connected in parallel to the negative control throttle 18, and is opened when the negative control pressure rises excessively, and discharges hydraulic oil upstream of the negative control throttle 18 to the tank. The valve 20b is a relief valve connected to the upstream side of the control valve 17, and opens part of the hydraulic oil discharged when the discharge pressure of the main pump 14 rises excessively to the tank. Discharge.

  The operation devices 26a and 26b are devices used by the operator for operating the hydraulic actuator. In the present embodiment, the content of the operation in the operation devices 26a and 26b is transmitted to the corresponding switching valve via the switching valve line. Specifically, the operating device 26a is an operating lever for operating the boom cylinder 7 and the bucket cylinder 9, and the operating device 26b is an operating lever for operating the arm cylinder 8.

  The gate lock lever 27 is a device that switches the state of the excavator. In the present embodiment, the gate lock lever 27 has a locked state in which the excavator is in a work-impossible state and a lock-released state in which the excavator is in a workable state. The “workable state” means a state in which the operator can operate the shovel, and the “work not possible state” means a state in which the operator cannot operate the shovel.

  The controller 30 is a control unit for controlling the excavator, and has lower control units such as a hydraulic system abnormality detection unit 30a and a fuel quality determination unit 30b.

  The engine controller 35 is a control unit for controlling the engine 11 and has lower control units such as an internal combustion engine system (engine system) abnormality detection unit 35a.

  The exhaust system 50 is a system for discharging the exhaust gas of the engine 11 to the outside. In the present embodiment, the exhaust system 50 mainly includes an exhaust pipe 50a, a DPF 50b, and a differential pressure sensor 50c. The exhaust pipe 50a is connected to the exhaust port of the engine 11 and exhausts exhaust gas discharged from the engine 11 to the outside. The DPF 50b is a filter that collects PM in the exhaust gas flowing through the exhaust pipe 50a. The differential pressure sensor 50 c detects a differential pressure between the upstream pressure and the downstream pressure of the DPF 50 b (hereinafter referred to as “DPF differential pressure”), and outputs the detected value to the engine controller 35. To do. The differential pressure sensor 50c may be composed of two pressure sensors that detect the upstream and downstream pressures of the DPF 50b.

  In the present embodiment, the controller 30 executes processing by each of the hydraulic system abnormality detection unit 30a and the fuel quality determination unit 30b based on outputs from the discharge pressure sensor 14a, the gate lock lever 27, the engine controller 35, and the like. Thereafter, the controller 30 appropriately outputs control signals corresponding to the processing results of the hydraulic system abnormality detection unit 30a and the fuel quality determination unit 30b to the display unit 31 and the like.

  The engine controller 35 executes processing by the engine system abnormality detection unit 35a based on outputs from the rotation speed sensor 11a, boost pressure sensor 11b, atmospheric pressure sensor 11c, water temperature sensor 11d, differential pressure sensor 50c, and the like. Thereafter, the engine controller 35 appropriately outputs a control signal corresponding to the processing result of the engine system abnormality detection unit 35a to the controller 30 or the like. Further, the engine controller 35 transfers the detection value of the differential pressure sensor 50 c to the controller 30. Note that the differential pressure sensor 50 c may directly output the detected value to the controller 30.

  Further, the engine controller 35 executes a regeneration process of the DPF 50b when a predetermined condition is satisfied. In this embodiment, the engine controller 35 automatically executes the regeneration process of the DPF 50b every time the excavator operating time reaches a predetermined time (for example, 8 hours). Further, the engine controller 35 automatically performs the regeneration process of the DPF 50b when the DPF differential pressure, which is the detection value of the differential pressure sensor 50c, exceeds the predetermined pressure even if the excavator operating time has not reached the predetermined time. Run. Further, the engine controller 35 may execute the reproduction process in response to an operator input via an input unit (not shown).

  Next, details of the hydraulic system abnormality detection unit 30a and the fuel quality determination unit 30b in the controller 30 and the engine system abnormality detection unit 35a in the engine controller 35 will be described.

  The hydraulic system abnormality detection unit 30a is a functional element that determines whether there is an abnormality in the hydraulic system. In this embodiment, the hydraulic system abnormality detection unit 30a determines that there is an abnormality in the hydraulic system when, for example, hunting of the discharge amount of the main pump 14 is detected based on the output of the discharge pressure sensor 14a or the like. This is because when the discharge amount of the main pump 14 is hunted, the engine load is also hunted, and the engine 11 easily injects fuel in accordance with the vertical fluctuation of the engine load and discharges black smoke (soot). Moreover, it is because DPF becomes easy to be clogged when the discharge amount of black smoke (soot) increases. When the hydraulic system abnormality detection unit 30a determines that there is an abnormality in the hydraulic system, the hydraulic system abnormality detection unit 30a causes the display unit 31 to display a warning message informing the operator of that fact. Specifically, the hydraulic system abnormality detection unit 30a causes the display unit 31 to display a warning message notifying the malfunction of the main pump 14 when detecting the hunting of the discharge amount of the main pump 14. The hydraulic system abnormality detection unit 30a may transmit a warning message to the outside through communication. This is because the operator of the excavator, the manager, the owner, etc. (hereinafter referred to as “operator etc.”) are encouraged to check the main pump 14. The hydraulic system abnormality detection unit 30a stores the determination result in the controller 30 so that it can be referred to.

  The engine system abnormality detection unit 35a is a functional element that determines whether there is an abnormality in the engine system. In this embodiment, the engine system abnormality detection unit 35a determines that there is an abnormality in the engine system when, for example, an abnormality of the atmospheric pressure sensor 11c is detected based on the output of the atmospheric pressure sensor 11c. This is because when the atmospheric pressure sensor 11c fails, the engine 11 cannot use the output of the atmospheric pressure sensor 11c, and has to determine the fuel injection timing on the assumption that the atmospheric pressure is a predetermined pressure. That is, the engine 11 cannot inject fuel at the optimal injection timing, and easily discharges black smoke (soot). Moreover, it is because DPF becomes easy to be clogged when the discharge amount of black smoke (soot) increases. If the engine system abnormality detection unit 35a determines that there is an abnormality in the engine system, the engine system abnormality detection unit 35a causes the display unit 31 to display a warning message informing the operator of that fact. Specifically, the engine system abnormality detection unit 35a causes the display unit 31 to display a warning message notifying the abnormality of the atmospheric pressure sensor 11c when the abnormality of the atmospheric pressure sensor 11c is detected. Further, the engine system abnormality detection unit 35a may transmit a warning message to the outside through communication. This is to prompt the operator or the like to check the atmospheric pressure sensor 11c. Further, the engine system abnormality detection unit 35a stores the determination result in the controller 30 so that it can be referred to.

  The fuel quality determination unit 30 b is a functional element that determines the quality of the fuel used in the engine 11. In this embodiment, the fuel quality determination unit 30b determines the quality of the fuel (whether there is a fuel abnormality) based on the outputs of the engine system abnormality detection unit 35a, the differential pressure sensor 50c, and the like. Then, when the fuel quality determination unit 30b determines that the fuel is abnormal and confirms that there is no abnormality in the engine system based on the determination result of the engine system abnormality detection unit 35a, the fuel is abnormal. Notify the operator to that effect.

  Here, with reference to FIG. 3, a process in which the fuel quality determination unit 30b determines the quality of the fuel (hereinafter referred to as “fuel quality determination process”) will be described. FIG. 3 is an example of a flowchart showing the flow of the fuel quality determination process, and the fuel quality determination unit 30b executes the fuel quality determination process every time the regeneration process of the DPF 50b is executed, for example.

  First, the fuel quality determination unit 30b determines whether or not the DPF 50b is clogged (step ST1). In this embodiment, the fuel quality determination unit 30b determines whether or not the DPF 50b is clogged based on the output from the differential pressure sensor 50c and the like. The details of the method for determining whether or not the DPF 50b is clogged will be described later.

  When it is determined that clogging has occurred in the DPF 50b (YES in step ST1), the fuel quality determination unit 30b confirms whether there is an abnormality in the engine system based on the determination result of the engine system abnormality detection unit 35a in the engine controller 35. (Step ST2).

  If the determination result of the engine system abnormality detection unit 35a is that there is an engine system abnormality (YES in step ST2), the fuel quality determination unit 30b determines that the fuel is not poor fuel and the engine system is abnormal, and the engine system is abnormal. An operator or the like is notified (step ST3). In the present embodiment, the fuel quality determination unit 30b causes the display unit 31 to display a warning message indicating that there is an abnormality in the engine system. Further, the fuel quality determination unit 30b may transmit a warning message to an external management device via communication. For example, the increase in the discharge amount of black smoke (soot), which is one of the causes of clogging of the DPF 50b, can be caused by any abnormality in the atmospheric pressure sensor 11c and the use of poor fuel as described above. Further, as long as an abnormality of the atmospheric pressure sensor 11c is detected, the inspection of the atmospheric pressure sensor 11c should be given top priority. At this time, since the DPF 50b is also clogged, a warning message indicating that the DPF 50b is clogged is displayed on the display unit 31 to prompt the operator to check the DPF.

  On the other hand, if the determination result of the engine system abnormality detection unit 35a is that there is no engine system abnormality (NO in step ST2), the fuel quality determination unit 30b determines that the fuel is poor and the DPF 50b is clogged. Is notified to the operator or the like (step ST4). In this embodiment, the fuel quality determination unit 30b causes the display unit 31 to display a warning message indicating that the DPF 50b is clogged. Further, the fuel quality determination unit 30b may transmit a warning message to an external management device via communication. At this time, since it can be determined that there is a high possibility that the clogging of the DPF 50b is caused by poor fuel, a warning message indicating that the fuel is abnormal is displayed on the display unit 31, and the operator checks the fuel. May be prompted.

  When it is determined that the DPF 50b is not clogged (NO in step ST1), the fuel quality determination unit 30b ends the current fuel quality determination process without notifying the operator or the like of any information. . And the fuel quality determination part 30b repeats this fuel quality determination process with a predetermined control period.

  As described above, when the fuel quality determination unit 30b determines that the DPF 50b is clogged and confirms that there is no abnormality in the engine system based on the determination result of the engine system abnormality detection unit 35a, It is determined that there is an abnormality. Therefore, the presence or absence of fuel abnormality can be determined with high reliability.

  Next, another embodiment of the fuel quality determination process will be described with reference to FIG. FIG. 4 is an example of a flowchart showing the flow of the fuel pass / fail judgment process according to the present embodiment. The fuel pass / fail judgment unit 30b performs the fuel pass / fail judgment process every time the regeneration process of the DPF 50b is executed, for example. Run. The flowchart of FIG. 4 is different from the flowchart of FIG. 3 in that it includes step ST12 for confirming whether there is an abnormality in the hydraulic system based on the determination result of the hydraulic system abnormality detection unit 30a, but is common in other points. Therefore, description of common points is omitted, and differences are described in detail.

  When it is determined that the DPF 50b is clogged (YES in step ST11), the fuel quality determination unit 30b checks whether there is an abnormality in the hydraulic system (step ST12). In the present embodiment, the fuel quality determination unit 30b refers to the determination result of the hydraulic system abnormality detection unit 30a to check whether there is an abnormality in the hydraulic system.

  When the determination result of the hydraulic system abnormality detection unit 30a is that there is an abnormality in the hydraulic system (YES in step ST12), the fuel quality determination unit 30b determines that the fuel is not a bad fuel but an abnormality in the hydraulic system, and the hydraulic system is abnormal. An operator or the like is notified (step ST13). In the present embodiment, the fuel quality determination unit 30b causes the display unit 31 to display a warning message indicating that there is an abnormality in the hydraulic system. Further, the fuel quality determination unit 30b may transmit a warning message to an external management device via communication. For example, the increase in the amount of black smoke (soot) emission, which is one of the causes of clogging of the DPF 50b, can be caused by both the hunting of the main pump 14 and the use of poor fuel as described above. Further, as long as an abnormality of the main pump 14 is detected, the inspection of the main pump 14 should be given top priority. At this time, since the DPF 50b is also clogged, a warning message indicating that the DPF 50b is clogged is displayed on the display unit 31 to prompt the operator to check the DPF.

  On the other hand, when the determination result of the hydraulic system abnormality detection unit 30a is that there is no hydraulic system abnormality (NO in step ST12), the fuel quality determination unit 30b determines whether there is an abnormality in the engine system based on the determination result of the engine system abnormality detection unit 35a. Is confirmed (step ST14). In addition, since the process after step ST14 is the same as the process after step ST2 of FIG. 3, the description is abbreviate | omitted.

  Further, in this embodiment, the fuel quality determination unit 30b confirms whether there is an abnormality in the engine system after confirming that there is no abnormality in the hydraulic system. However, the present invention is not limited to this configuration. For example, the fuel quality determination unit 30b may confirm whether there is an abnormality in the hydraulic system after confirming that there is no abnormality in the engine system, and simultaneously determine whether there is an abnormality in the hydraulic system and whether there is an abnormality in the engine system. You may check.

  Further, in this embodiment, the fuel quality determination unit 30b confirms whether there is an abnormality in the engine system when it is confirmed that there is an abnormality in the hydraulic system based on the determination result of the hydraulic system abnormality detection unit 30a. Absent. However, the present invention is not limited to this configuration. For example, the fuel quality determination unit 30b confirms that there is an abnormality in the hydraulic system based on the determination result of the hydraulic system abnormality detection unit 30a, and then detects an abnormality in the engine system based on the determination result of the engine system abnormality detection unit 35a. The presence or absence of may be confirmed.

  As described above, the fuel quality determination unit 30b determines that the fuel is abnormal when it is determined that the DPF 50b is clogged and it is confirmed that there is no abnormality in either the hydraulic system or the engine system. Therefore, the presence or absence of fuel abnormality can be determined with high reliability.

  Next, a method for determining clogging of the DPF 50b that is determined by the fuel quality determining unit 30b will be described with reference to FIGS. FIG. 5 is a schematic diagram showing the relationship between the excavator operating time and the DPF differential pressure. In FIG. 5, a solid triangular wave transition TC represents a temporal transition of the DPF differential pressure when the poor fuel is used, and a broken triangular wave transition TC1 is a DPF differential pressure when the high quality fuel is used. It represents the time transition. Also, a solid line BC that rises to the right represents a temporal transition of the reference DPF differential pressure when using poor fuel, and a broken line that rises to the right of BC1 represents the reference DPF differential pressure when using good quality fuel. It represents the time transition. The “reference DPF differential pressure” means an estimated value of the DPF differential pressure after the regeneration process derived from the operation time.

  As described above, the DPF 50b is automatically subjected to the regeneration process every time the excavator operating time reaches a predetermined time (for example, 8 hours). Therefore, as shown in FIG. 5, until the DPF differential pressure exceeds the predetermined pressure Pth (see the dotted line), the DPF differential pressure changes in a triangular wave shape regardless of whether poor fuel or good quality fuel is used. To do. That is, the DPF differential pressure gradually increases as the operating time of the excavator increases until the next regeneration process is performed after the regeneration process, and is reduced by the subsequent regeneration process. In this case, the regeneration process execution interval Ta when using poor fuel and the regeneration process execution interval Ta1 when using high-quality fuel are both equal to a predetermined time.

  Further, when the DPF differential pressure output from the differential pressure sensor 50c exceeds the predetermined pressure Pth, the DPF 50b is automatically subjected to the regeneration process even if the excavator operating time after the previous regeneration process is less than the predetermined time. . 5 indicates a state where the DPF differential pressure exceeds the predetermined pressure Pth. In this case, the regeneration process execution interval Tb1 when the high quality fuel is used is equal to the predetermined time, whereas the regeneration process execution interval Tb when the poor fuel is used is less than the predetermined time.

  In addition, as indicated by the transition BC1, the reference DPF differential pressure when using high quality fuel increases at a relatively high rate at first, but when the cumulative operating time of the shovel reaches a certain amount of time. It remains almost flat. This is because, at the beginning, PM accumulates on the peripheral portion of the DPF 50b that cannot be removed by the regeneration process. Further, after the accumulated operating time of the excavator reaches a certain time, PM accumulated in a portion removable by the regeneration process is repeatedly burned and removed by the regeneration process.

  On the other hand, as indicated by the transition BC, the reference DPF differential pressure when using poor fuel rises higher than when using high-quality fuel even after the excavator's cumulative operating time reaches a certain amount of time. Continue to rise at a rate. This is because PM such as ash that cannot be removed by the regeneration process gradually accumulates in the DPF 50b.

  In addition, the average rate of increase in the DPF differential pressure between two successive regeneration processes is higher when poor fuel is used than when high quality fuel is used. This is because when poor fuel is used, the amount of PM emission such as black smoke (soot) is larger than when high quality fuel is used.

  Therefore, the fuel pass / fail judgment unit 30b uses the judgment condition based on the above-described difference between the transition TC when the poor fuel is used and the transition TC1 when the good fuel is used, and the degree of clogging of the DPF 50b. Judging. In the present embodiment, the fuel quality determination unit 30b determines whether or not the DPF 50b is clogged using the following determination conditions.

  6 to 10 are explanatory diagrams of the determination conditions, respectively, and are enlarged views of a part of the temporal transition TC of the DPF differential pressure when the poor fuel as shown in FIG. 5 is used. In addition, the black block arrow in each of FIGS. 6-10 represents that the reproduction | regeneration processing was performed.

  FIG. 6 is an explanatory diagram of a determination condition (hereinafter referred to as “first determination condition”) as to whether or not the execution interval of the reproduction process has continued for a predetermined number of times and falls below a predetermined time.

  Specifically, FIG. 6 shows that the regeneration processes R3 and R4 are started without waiting for the elapse of the predetermined time Tth because the DPF differential pressure exceeds the predetermined pressure Pth. In this case, the execution interval T2 between the reproduction process R2 and the reproduction process R3 and the execution interval T3 between the reproduction process R3 and the reproduction process R4 are both less than the predetermined time Tth.

  As a result, the fuel quality determination unit 30b determines that the DPF 50b is clogged, assuming that the execution interval of the regeneration process has continued twice and falls below a predetermined time.

  FIG. 7 is an explanatory diagram of a determination condition (hereinafter referred to as “second determination condition”) indicating whether or not the execution interval of the reproduction process has been shortened a predetermined number of times.

  Specifically, FIG. 7 shows that the regeneration processes R3, R4, and R5 are started without waiting for the elapse of the predetermined time Tth because the DPF differential pressure exceeds the predetermined pressure Pth. In this case, the execution interval T2 between the reproduction process R2 and the reproduction process R3, the execution interval T3 between the reproduction process R3 and the reproduction process R4, and the execution interval T4 between the reproduction process R3 and the reproduction process R4 are as follows. In either case, the time is less than the predetermined time Tth. Further, in the present embodiment, since the PM that is difficult to burn that accumulates in the DPF 50b increases with time, the decrease width of the DPF differential pressure that is decreased by each of the regeneration processes R1 to R4 gradually decreases, and the execution interval T1 ~ T4 is also gradually shortened.

  As a result, the fuel quality determination unit 30b determines that the DPF 50b is clogged, assuming that the execution interval of the regeneration process has been shortened three times in succession.

  FIG. 8 shows a determination condition (hereinafter, “third determination condition”) indicating whether or not the average rate of increase in the DPF differential pressure between the execution of the previous regeneration process and the execution of the current regeneration process exceeds a predetermined value. ).

  Specifically, FIG. 8 shows that the average increase rate α2 of the DPF differential pressure after the execution of the regeneration process R2 and before the execution of the regeneration process R3 is determined after the regeneration process R1 and before the regeneration process R2. It shows that it is larger than the average rate of increase α1 of the DPF differential pressure. This is because PM which is difficult to burn and accumulates in the DPF 50b increases with time, and the DPF differential pressure easily increases. FIG. 8 shows that the average rate of increase α2 is larger than the predetermined value αth in the partially enlarged view surrounded by a dotted circle.

  As a result, the fuel quality determination unit 30b assumes that the average rate of increase α2 of the DPF differential pressure between the execution of the regeneration process R2 and the execution of the regeneration process R3 exceeds the predetermined value αth, and the DPF 50b is clogged. It is determined that The fuel quality determination unit 30b compares the average increase rate α1 and the average increase rate α2, and determines that the DPF 50b is clogged when it is determined that the average increase rate is increasing (α1 <α2). May be.

  FIG. 9 shows a determination condition (hereinafter referred to as “the difference between the decrease range of the DPF differential pressure decreased by the current regeneration process” and the decrease range of the DPF differential pressure decreased by the previous regeneration process exceeds a predetermined value. It is referred to as “fourth determination condition”).

  Specifically, FIG. 9 shows that the decrease width D1 of the DPF differential pressure decreased by the regeneration process R1 is larger than the decrease width D2 of the DPF differential pressure decreased by the regeneration process R2. This is because PM which is difficult to burn and accumulates in the DPF 50b increases with time, and the DPF differential pressure easily increases. FIG. 9 shows that the difference V1 between the decrease width D1 and the decrease width D2 is larger than the predetermined value Vth in the partially enlarged view surrounded by the dotted circle.

  As a result, the fuel quality determination unit 30b assumes that the difference V1 between the decrease range D1 of the DPF differential pressure decreased by the regeneration process R1 and the decrease width D2 of the DPF differential pressure decreased by the regeneration process R2 exceeds the predetermined value Vth. It is determined that the DPF 50b is clogged.

  FIG. 10 illustrates a determination condition (hereinafter referred to as “fifth determination condition”) indicating whether or not the number of times the DPF differential pressure after the regeneration process has been performed has not decreased to the reference DPF differential pressure exceeds a predetermined number. FIG. In FIG. 10, the DPF differential pressure after the regeneration process is represented by a black circle, and the reference DPF differential pressure after the regeneration process is represented by a white circle.

  Specifically, FIG. 10 shows that the DPF differential pressure P1 after the regeneration process R1 is executed is equal to the reference DPF differential pressure Q1, and the DPF differential pressure P2 after the regeneration process R2 is executed is larger than the reference DPF differential pressure Q2. Show. FIG. 10 shows that the DPF differential pressure P3 after the regeneration process R3 is greater than the reference DPF differential pressure Q3, the DPF differential pressure P4 after the regeneration process R4 is equal to the reference DPF differential pressure Q4, and the regeneration process R5. It shows that the DPF differential pressure P5 after execution is larger than the reference DPF differential pressure Q5. In this case, FIG. 10 shows that in the three regeneration processes R2, R3, and R5 of the five regeneration processes R1 to R5, the DPF differential pressure after the regeneration process is greater than the reference DPF differential pressure. .

  As a result, when the regeneration process R5 ends, the fuel quality determination unit 30b assumes that the number of times the DPF differential pressure after the regeneration process has not decreased to the reference DPF differential pressure has exceeded two times, and the DPF 50b It is determined that clogging has occurred.

  Further, the fuel quality determination unit 30b may determine the degree of clogging of the DPF 50b using a determination condition (hereinafter referred to as “sixth determination condition”) indicating whether or not the regeneration process has been manually started. . Specifically, the fuel quality determination unit 30b determines that the DPF 50b is clogged when the regeneration process is manually started. Note that the manual regeneration process is executed after the excavator is in a work-impossible state. Specifically, since the load applied to the engine is small, manual regeneration is prompted by a message display or the like when the exhaust temperature does not become high. The manual regeneration process is executed, for example, with the gate lock lever 27 in a locked state and the excavator in an unworkable state. The manual regeneration process is interrupted when, for example, the gate lock lever 27 is unlocked and the excavator is in a workable state.

  Thus, the fuel quality determination unit 30b determines the degree of clogging of the DPF 50b using at least one of the first to sixth determination conditions. Specifically, the fuel quality determination unit 30b determines whether the DPF 50b is clogged using at least one of the first to sixth determination conditions.

  Further, the fuel quality determination unit 30b may determine the quality of the fuel by additionally considering the load factor of the engine 11 and the DPF differential pressure. Specifically, the fuel quality determination unit 30b calculates the load factor of the engine 11 based on outputs from the discharge pressure sensor 14a, the engine controller 35, and the like. The load factor of the engine 11 is calculated as, for example, the ratio of the absorption horsepower of the main pump 14 to the output horsepower of the engine 11. Alternatively, it may be calculated based on the ratio between the current injection amount and the injection amount at the rated output determined for each engine speed. When determining based on the load factor, the fuel pass / fail determination unit 30b determines that the fuel quality is determined when the DPF differential pressure exceeds the predetermined value even though the average value of the load factor of the engine 11 in the predetermined time exceeds the predetermined value. Is temporarily determined to be abnormal. This is because when high-quality fuel is used, if the average value of the load factor of the engine 11 is high, the DPF 50b becomes high temperature, PM in the DPF 50b is burned and removed by self-regeneration, and the DPF differential pressure should decrease. In other words, when poor fuel is used, even if the DPF 50b becomes high temperature due to the high average load factor of the engine 11, the PM that is difficult to burn is not removed by combustion, and the DPF differential pressure decreases. It is because it does not.

  Then, the fuel quality determination unit 30b determines the quality of the fuel based on the clogging of the DPF 50b and the output of the engine system abnormality detection unit 35a. In this case, even if the fuel quality determination unit 30b can determine that the fuel is abnormal based on the clogging of the DPF 50b and the output of the engine system abnormality detection unit 35a, the load factor of the engine 11 and the DPF difference If it is temporarily determined that there is no abnormality in the fuel based on the pressure, the final determination may be made that there is no abnormality in the fuel. The same applies to the case where the quality of the fuel is determined based on the clogging of the DPF 50b, the output of the hydraulic system abnormality detection unit 30a, and the output of the engine system abnormality detection unit 35a.

  With the above configuration, the controller 30 determines that the fuel is abnormal when it is determined that the DPF 50b is clogged and it is confirmed that there is no abnormality in the engine system. Alternatively, the controller 30 determines that the fuel is abnormal when determining that the DPF 50b is clogged and confirming that there is no abnormality in either the hydraulic system or the engine system. Therefore, the presence or absence of fuel abnormality can be determined with high reliability. Moreover, the presence or absence of fuel abnormality can be determined at an early stage, and adverse effects on other parts of the engine 11 such as an injector, an exhaust gas recirculation system, and a supercharger can be prevented.

  The controller 30 functions as a component independent of the engine controller 35, and determines whether the DPF 50b is clogged and whether the fuel is good or bad. Therefore, the reliability of the determination result can be improved. However, the controller 30 and the engine controller 35 may be configured integrally.

  Further, the controller 30 determines the degree of clogging of the DPF 50b using at least one of the first to sixth determination conditions described above. Specifically, the controller 30 determines the degree of clogging of the DPF 50b using any combination of the first to sixth determination conditions described above. Therefore, it can be determined with high reliability whether or not the DPF 50b is clogged.

  Further, the controller 30 determines whether or not there is a fuel abnormality by additionally considering the load factor of the engine 11 and the DPF differential pressure. Therefore, the presence or absence of fuel abnormality can be determined with higher reliability.

  Although the preferred embodiments of the present invention have been described in detail above, the present invention is not limited to the above-described embodiments, and various modifications and substitutions can be made to the above-described embodiments without departing from the scope of the present invention. Can be added.

  For example, the controller 30 uses any of the first to sixth determination conditions described above according to the accumulated operating time of the excavator after starting to use a new DPF or after exchanging the DPF, or You may determine which combination of the above-mentioned 1st-6th determination conditions is used. For example, the controller 30 uses the first determination condition when the excavator accumulated operating time is less than a predetermined time, and combines the second determination condition and the third determination condition when the excavator accumulated operating time is equal to or longer than the predetermined time. It may be used to determine whether the DPF 50b is clogged.

  In addition, the controller 30 may determine a determination condition or a combination of determination conditions to be employed according to the surrounding environment such as weather, temperature, humidity, and atmospheric pressure.

  Further, the controller 30 determines whether the DPF 50b has a repeating pattern of DPF differential pressure that changes in a triangular wave shape (a pattern drawn by the DPF differential pressure that decreases after the start of the regeneration process and increases until the next regeneration process is started). You may determine the presence or absence of clogging. For example, the controller 30 may determine that the DPF 50b is clogged when the current repetitive pattern changes more than a predetermined degree compared to the previous repetitive pattern. The predetermined degree is based on, for example, the decrease in the DPF differential pressure, the average increase rate of the DPF differential pressure, the minimum value of the DPF differential pressure immediately after execution of the regeneration process, the maximum value of the DPF differential pressure immediately before execution of the regeneration process, and the like. Determined.

  In the above-described embodiment, the quality of the fuel used in the engine 11 is determined by the fuel quality determination unit 30b of the controller 30. However, the present invention is not limited to this configuration. For example, the quality of fuel used in the engine 11 may be determined by a management device outside the excavator. In this case, the management device includes a determination processing unit that determines whether or not the fuel is good and a display unit that displays a determination result by the determination processing unit. Then, the determination processing unit determines the quality of the fuel based on the degree of clogging of the DPF 50b based on the output of the pressure sensor transmitted from the shovel and the determination result of the engine system abnormality detection unit 35a. In addition, the determination processing unit transmits fuel based on the degree of clogging of the DPF 50b based on the output of the pressure sensor, the determination result of the engine system abnormality detection unit 35a, and the determination result of the hydraulic system abnormality detection unit 30a transmitted from the shovel. You may determine the quality of.

  DESCRIPTION OF SYMBOLS 1 ... Lower traveling body 2 ... Turning mechanism 3 ... Upper turning body 4 ... Boom 5 ... Arm 6 ... Bucket 7 ... Boom cylinder 8 ... Arm cylinder 9 ... Bucket cylinder 10 ... cabin 11 ... engine 11a ... rotational speed sensor 11b ... boost pressure sensor 11c ... atmospheric pressure sensor 11d ... water temperature sensor 13 ... regulator 14 ... main Pump 14a ... Discharge pressure sensor 17 ... Control valve 17a ... Switching valve for boom 17b ... Switching valve for arm 17c ... Switching valve for bucket 18 ... Negative control throttle 19 ... For negative control Pilot lines 20a, 20b ... relief valve 26 ... operating device 27 ... gate lock lever 30 ... controller 30a ... Hydraulic system abnormality detection unit 30b ... Fuel quality determination unit 31 ... Display unit 35 ... Engine controller 35a ... Engine system abnormality detection unit 50 ... Exhaust system 50a ... Exhaust pipe 50b ... DPF 50c ... Differential pressure sensor

Claims (7)

A lower traveling body,
An upper swing body that is rotatably mounted on the lower traveling body;
A work attachment mounted on the upper swing body;
A plurality of hydraulic actuators for driving the work attachment;
A main pump for supplying pressure oil to the plurality of hydraulic actuators mounted on the upper swing body;
A control unit for controlling the plurality of hydraulic actuators mounted on the upper swing body;
An internal combustion engine that is mounted on the upper rotating body and that rotationally drives the main pump;
An internal combustion engine system abnormality detection unit for detecting abnormality of the internal combustion engine;
A filter that is mounted on the upper rotating body and that is provided in an exhaust passage of the internal combustion engine to collect particulate matter in the exhaust;
A pressure sensor attached to the filter,
The internal combustion engine is controlled to maintain a predetermined rotational speed;
The control unit includes a fuel quality determination unit that determines quality of the fuel based on the degree of clogging of the filter determined based on the output of the pressure sensor and the output of the internal combustion engine system abnormality detection unit.
Excavator. An internal combustion engine controller for controlling the internal combustion engine;
The internal combustion engine control unit determines whether the internal combustion engine is abnormal based on an output of the internal combustion engine system abnormality detection unit, and transmits a result of the determination to the control unit;
The excavator according to claim 1. A hydraulic system abnormality detection unit for detecting an abnormality in the plurality of hydraulic actuators and the main pump;
The fuel quality determination unit is configured to determine whether the fuel is clogged based on the degree of clogging of the filter determined based on the output of the pressure sensor, the output of the internal combustion engine system abnormality detection unit, and the output of the hydraulic system abnormality detection unit. Judge pass / fail,
The shovel according to claim 1 or 2. The pressure sensor detects a differential pressure before and after the filter;
The filter is regenerated by a regenerating process every time the excavator operating time reaches a predetermined time or when the differential pressure exceeds a predetermined pressure,
4. The control unit according to claim 1, wherein the control unit determines that the filter is clogged when a repeating pattern of the differential pressure formed for each regeneration process changes beyond a predetermined degree. 5. Excavator. The pressure sensor detects a differential pressure before and after the filter;
The filter is regenerated by a regenerating process every time the excavator operating time reaches a predetermined time or when the differential pressure exceeds a predetermined pressure,
The degree of clogging of the filter is as follows:
Whether or not the execution interval of the reproduction process has continued for a predetermined number of times and falls below a predetermined time,
Whether or not the playback processing execution interval has been shortened a predetermined number of times,
Whether or not the average rate of increase in the differential pressure between the execution of the previous regeneration process and the execution of the current regeneration process exceeds a predetermined value,
Whether the average rate of increase of the differential pressure this time is greater than the average rate of increase of the differential pressure of the previous time,
Whether or not the difference between the reduction range of the differential pressure reduced by the current regeneration process and the reduction range of the differential pressure reduced by the previous regeneration process exceeds a predetermined value,
Whether or not the number of times the differential pressure after the regeneration process has not decreased to a predetermined reference pressure exceeds a predetermined number; and
Whether or not the playback process was started manually,
Is determined using at least one determination condition.
The excavator according to any one of claims 1 to 3. The fuel quality determination unit determines the quality of the fuel by additionally considering a load factor of the internal combustion engine and a differential pressure before and after the filter detected by the pressure sensor.
The excavator according to any one of claims 1 to 5. A lower traveling body, an upper revolving body that is pivotably mounted on the lower traveling body, a work attachment mounted on the upper revolving body, a plurality of hydraulic actuators that drive the work attachment, and the upper revolving body A main pump that supplies pressure oil to the plurality of hydraulic actuators; a control unit that controls the plurality of hydraulic actuators; and that is mounted on the upper swing body; An internal combustion engine that is controlled to rotate a main pump and maintain a predetermined rotational speed, an internal combustion engine system abnormality detection unit that detects abnormality of the internal combustion engine, and the internal combustion engine that is mounted on the upper swing body An excavator management device having a filter for collecting particulate matter in the exhaust provided in an exhaust passage of the gas, and a pressure sensor attached to the filter I,
A determination processing unit that determines the quality of the fuel based on the degree of clogging of the filter based on the output of the pressure sensor and the determination result of the internal combustion engine system abnormality detection unit transmitted from the excavator;
A display unit for displaying a determination result by the determination processing unit,
Excavator management device.

Images