JP2016166537A - Engine and work vehicle with the engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide for an engine performing forcible regeneration of a DPF (Diesel Particulate Filter) under a predetermined condition, configuration allowing for estimation of a remaining time to timing when the forcible regeneration is required.SOLUTION: An engine comprises an engine body with a DPF, and an ECU 90. The ECU 90 can perform control for shifting to a plurality of regeneration modes of removing PM (Particulate Matter) collected by and accumulated in the DPF by oxidizing the same (including a reset regeneration mode that is a forcible regeneration mode of forcibly increasing an amount of the PM to be oxidized). The ECU 90 comprises a remaining time calculation part 94 and a remaining time output part 95. The remaining time calculation part 94 calculates a remaining time to timing when regeneration of the DPF by the reset regeneration mode is required, on the basis of at least one of an accumulated amount of the PM in the DPF and an operating time of the engine body. The remaining time output part 95 outputs the remaining time calculated by the remaining time calculation part 94.SELECTED DRAWING: Figure 4

Description

  The present invention mainly relates to an engine including an exhaust gas purification device.

  2. Description of the Related Art Conventionally, a particulate soot filter (DPF: Diesel Particulate Filter) that is provided in an exhaust path of an engine and collects and removes particulate matter (PM) in exhaust gas is known. Since the PM collected by the DPF increases with the operation of the engine, it is necessary to remove the PM deposited on the DPF at an appropriate timing. A general method for removing PM includes burning the PM into harmless carbon dioxide (hereinafter referred to as DPF regeneration).

  Patent document 1 discloses the diesel engine connected to the muffler which plays the role of this kind of DPF. The diesel engine disclosed in Patent Document 1 is configured to be connected to a muffler in which at least a diesel particulate soot filter is installed among an oxidation catalyst and a diesel particulate soot filter.

JP 2008-31955 A

  In the diesel engine disclosed in Patent Document 1, when the engine is operated at a low load or idling, the exhaust temperature is lowered, so that PM accumulated in the exhaust gas purification device is effectively removed. I can't.

  Therefore, in the prior art, by controlling the fuel injection timing or increasing the engine load, the exhaust temperature is raised and the PM accumulated in the exhaust gas purification device is forcibly burned off. Forced regeneration was executed.

  By the way, as a method of forced regeneration, there are a method of performing forced regeneration while operating the engine as usual, and a method of greatly restricting the operation of the engine. Hereinafter, the former may be referred to as a first forced regeneration mode, and the latter may be referred to as a second forced regeneration mode. Normally, in the second forced regeneration mode, it is not possible to substantially work with a machine equipped with an engine. Therefore, from the viewpoint of not reducing the convenience of the machine, it is preferable to perform the DPF regeneration with priority on the first forced regeneration mode.

  However, if the forced regeneration is performed, the exhaust gas of the engine becomes a high temperature. Even in the first forced regeneration mode, forced regeneration may be performed depending on the place where the engine is mounted. It may not always be appropriate. If forced regeneration of the engine is necessary when working at a place where forced regeneration is inappropriate, the operator must stop the work and execute forced regeneration once away from the place. In this case, the operator is forced to change the work schedule, and the work efficiency is greatly reduced.

  On the other hand, it is configured so that the operator can delay the transition to the first forced regeneration mode, the operator postpones the forced regeneration, and completes the work in a place where the forced regeneration is inappropriate, It may be possible to perform forced regeneration after moving to another location. However, there is a limit to the forced regeneration postponement because PM accumulates further during the work. In extreme cases, it is necessary to shift to the second forced regeneration mode in which the use of the machine is greatly restricted, There was a risk that special maintenance work would be required.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a configuration capable of predicting the remaining time until the timing at which the forced regeneration is necessary in an engine that performs forced regeneration of the DPF under a predetermined condition. There is to do.

Means and effects for solving the problems

  The problems to be solved by the present invention are as described above. Next, means for solving the problems and the effects thereof will be described.

  According to a first aspect of the present invention, an engine having the following configuration is provided. That is, this engine is provided with an exhaust gas purification device for purifying exhaust gas. The engine has a plurality of regeneration modes in which particulate matter collected and deposited in the exhaust gas purification device is removed by oxidizing. The engine includes an engine body and a control unit. The exhaust gas purification device is disposed in the engine body. The control unit can control to shift to a plurality of regeneration modes for removing particulate matter in the exhaust gas purification device. The plurality of regeneration modes include at least a forced regeneration mode for forcibly increasing the amount of the particulate matter to be oxidized. The control unit includes a remaining time calculation unit and a remaining time output unit. The remaining time calculation unit needs to regenerate the exhaust gas purification device in the forced regeneration mode based on at least one of the accumulated amount of the particulate matter in the exhaust gas purification device and the operation time of the engine body. The remaining time until the forced regeneration necessary timing is calculated. The remaining time output unit outputs the remaining time calculated by the remaining time calculation unit.

  Thus, the operator can grasp the remaining time until the timing at which forced regeneration of the exhaust gas purifying device in the engine is required. Therefore, for example, the operator can avoid operating the engine in a place that is not suitable for forced regeneration in a time zone where forced regeneration is required, or can complete forced regeneration before operating the engine in that place. it can. In this way, the operator can reasonably plan work using the engine in relation to the timing at which forced regeneration is necessary.

  The engine preferably has the following configuration. That is, the control unit further includes an emission amount calculation unit and an oxidation amount calculation unit. The emission amount calculation unit calculates an emission amount that is an amount of the particulate matter discharged from the engine body to the exhaust gas purification device. The oxidation amount calculation unit calculates an oxidation amount that is an amount of the particulate matter oxidized by the exhaust gas purification device. The control unit uses the emission amount calculated by the emission amount calculation unit and the oxidation amount calculated by the oxidation amount calculation unit to deposit the particulate matter in the exhaust gas purification apparatus. Calculate

  As a result, the amount of particulate matter deposited in the exhaust gas purifying apparatus can be accurately predicted, so that the remaining time until the timing at which forced regeneration is required in the engine can be calculated more accurately.

  The engine preferably has the following configuration. That is, the exhaust gas purification device includes a soot filter and a differential pressure sensor. The soot filter collects the particulate matter. The differential pressure sensor detects a pressure difference of the exhaust gas between the upstream side and the downstream side of the soot filter. The control unit calculates the accumulation amount of the particulate matter in the exhaust gas purification device based on a detection result of the differential pressure sensor.

  As a result, the amount of particulate matter deposited in the exhaust gas purification device can be accurately predicted.

  The engine preferably has the following configuration. That is, the control unit includes a first condition in which the amount of the particulate matter accumulated in the exhaust gas purification device is equal to or greater than a predetermined threshold value, and a second condition in which the operation time of the engine body is equal to or greater than a predetermined time. If at least one of the conditions is satisfied, it is determined that regeneration of the exhaust gas purifying device in the forced regeneration mode is necessary. The remaining time calculation unit includes: a first time that is a remaining time until the forced regeneration necessary timing related to the first condition; and a second time that is a remaining time to the forced regeneration necessary timing related to the second condition. Of these, the remaining time is defined as the remaining time.

  Thereby, in an engine having a condition for shifting to a plurality of forced regeneration modes, the timing at which forced regeneration is required can be output more accurately, so that the operator can more appropriately plan the operation of the engine.

  The engine preferably has the following configuration. That is, the control unit further includes a deposition amount increase / decrease trend calculation unit and an increase / decrease trend output unit. The accumulation amount increase / decrease tendency calculation unit calculates an increase / decrease tendency of the particulate matter in the exhaust gas purification device based on an operating state of the engine body. The increase / decrease trend output unit outputs the increase / decrease trend calculated by the accumulation amount increase / decrease trend calculation unit.

  Thereby, the operator can grasp whether the work currently being performed using the engine increases or decreases the amount of particulate matter deposited. Therefore, the operator delays the timing of forced regeneration in the engine by operating the engine in an operating state that is advantageous (or disadvantageous) with respect to regeneration of the exhaust gas purification device according to circumstances such as a work schedule ( (Or advance).

  According to a second aspect of the present invention, a work vehicle having the following configuration is provided. That is, this work vehicle includes the engine and the display unit. The display unit can display the remaining time output from the remaining time output unit.

  Thereby, the operator of the work vehicle can easily confirm the remaining time until the timing at which forced regeneration is necessary based on the display on the display unit. Therefore, the operator can rationally plan the work using the work vehicle according to the remaining time until the timing at which forced regeneration is required. As a result, the convenience of the work vehicle can be improved.

  According to a third aspect of the present invention, a work vehicle having the following configuration is provided. That is, this work vehicle includes the engine and the display unit. The said display part can display the said increase / decrease tendency output from the said increase / decrease tendency output part.

  Thereby, the operator of the work vehicle can easily confirm whether the current work is to increase or decrease the amount of particulate matter deposited based on the display on the display unit. Therefore, the operator defers (or puts forward) the timing at which forced regeneration is necessary by performing an operation that is advantageous (or disadvantageous) with respect to the regeneration of the exhaust gas purifying device according to circumstances such as the work schedule. Easy to do. As a result, the convenience of the work vehicle can be improved.

A side view showing a tractor provided with an engine concerning one embodiment of the present invention. Explanatory drawing which shows typically the flow of engine intake, exhaust, and fuel supply. Sectional drawing which shows the structure of DPF roughly. The block diagram which shows the structure for controlling an engine. The torque diagram which shows the continuous regeneration area | region and forced regeneration area | region of DPF. The figure explaining the reproduction mode which an engine has. The graph which shows a mode that forced regeneration of DPF is performed. The front view of the meter panel seen from the cockpit of the tractor. The figure explaining calculation of PM accumulation amount performed by ECU. (A) The figure which shows calculation of the time until the timing which requires forced regeneration. (B) The figure explaining the process which judges the increase / decrease tendency of the accumulation amount of PM.

  Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a side view showing a tractor 110 including an engine 100 according to an embodiment of the present invention. FIG. 2 is an explanatory diagram schematically showing intake and exhaust flows of the engine 100. FIG. 3 is a cross-sectional view schematically showing the configuration of the DPF 60. FIG. 4 is a block diagram illustrating a configuration for controlling engine 100.

  The engine 100 of this embodiment is configured as a diesel engine mounted on a tractor (work vehicle) 110 shown in FIG. As shown in FIG. 2, the engine 100 includes an engine body 10 and an ECU (engine control unit) 90 that is a control unit.

  The engine body 10 mainly includes an intake section 2 for sucking air from the outside, a cylinder (not shown) having a combustion chamber 3 for fuel, an exhaust section 4 for discharging exhaust gas generated by fuel combustion to the outside, It has.

  The intake section 2 includes an intake pipe 21 that is an intake passage. The intake section 2 includes a supercharger 22, an intake valve 23, and an intake manifold 24 that are arranged in order from the upstream side in the direction in which intake air flows in the intake pipe 21.

  The intake pipe 21 is an intake passage, and is configured to connect the supercharger 22, the intake valve 23, and the intake manifold 24. Air sucked from the outside can flow inside the intake pipe 21.

  As shown in FIG. 2, the supercharger 22 includes a turbine wheel 221, a shaft 222, and a compressor wheel 223. One end of the shaft 222 is connected to the turbine wheel 221, and the other end is connected to the compressor wheel 223. The turbine wheel 221 is configured to rotate using exhaust gas. The compressor wheel 223 connected to the turbine wheel 221 via the shaft 222 rotates as the turbine wheel 221 rotates. By the rotation of the compressor wheel 223, the air purified by an air cleaner (not shown) can be compressed and forcibly sucked.

  The intake valve 23 changes the cross-sectional area of the intake passage by adjusting the opening degree according to a control command from the ECU 90. Thereby, the amount of air supplied to the intake manifold 24 via the intake valve 23 can be adjusted.

  The intake manifold 24 is configured to distribute the air supplied from the intake pipe 21 according to the number of cylinders of the engine body 10 and supply the air to the combustion chambers 3 of the respective cylinders.

  An unillustrated intercooler that cools the compressed air sucked by the supercharger 22 by heat exchange with cooling water or flowing air (that is, wind) may be installed on the downstream side of the supercharger 22. good.

  In the combustion chamber 3, the air supplied from the intake manifold 24 is compressed, and fuel is injected into the compressed air that has become high temperature to cause spontaneous ignition, thereby generating combustion in the combustion chamber 3 and moving the piston up and down. . The power thus obtained is transmitted to a predetermined device (for example, the transmission of the tractor 110) via a crankshaft or the like.

  As shown in FIG. 2, the engine body 10 of the present embodiment includes a fuel tank 81 for storing fuel, a fuel filter 82, a fuel pump 83, a common rail 84, and an injector 85.

  The fuel stored in the fuel tank 81 passes through the fuel filter 82 and is then pumped to the common rail 84 by the fuel pump 83. Each injector 85 disposed in each combustion chamber 3 opens and closes in accordance with an instruction from the ECU 90 to inject fuel stored in the common rail 84 at a high pressure into each combustion chamber 3 at a predetermined timing.

  Exhaust gas generated by the combustion of fuel in the combustion chamber 3 is discharged from the combustion chamber 3 to the outside of the engine body 10 via the exhaust part 4.

  The exhaust unit 4 includes an exhaust pipe 41 that is an exhaust gas passage. Further, the exhaust unit 4 includes an exhaust manifold 42, an exhaust valve 43, and a DPF 60 that is an exhaust gas purification device, which are arranged in order from the upstream side in the direction in which the exhaust gas flows in the exhaust pipe 41.

  Further, the engine main body 10 includes an EGR device 50, and a part of the exhaust gas can be recirculated to the intake side via the EGR device 50 as shown in FIG. The EGR device 50 is provided with an EGR cooler 51 and an EGR valve 52. The EGR cooler 51 cools the exhaust gas recirculated to the intake air. The EGR valve 52 is configured to be able to adjust the recirculation amount of the exhaust gas. The EGR device 50 with the cooling function configured as described above can lower the maximum combustion temperature during, for example, high-load operation of the engine 100, so that the amount of NOx (nitrogen oxide) generated can be reduced. .

  The exhaust pipe 41 is an exhaust gas passage and is configured to connect the exhaust manifold 42, the exhaust valve 43, and the DPF 60, and allows the exhaust gas exhausted from the combustion chamber 3 to flow through the exhaust pipe 41. Can do.

  The exhaust manifold 42 collects the exhaust gas generated in each combustion chamber 3 and guides the exhaust gas to the exhaust pipe 41 so as to supply the exhaust gas to the turbine wheel 221 of the supercharger 22.

  Exhaust valve 43 is configured as a throttle valve, and can adjust the amount of exhaust gas exhausted to the outside of engine 100. For example, the ECU 90 controls the exhaust valve 43 by sending a control command so as to realize an appropriate exhaust pressure.

  The DPF 60 is provided at the outlet of the exhaust pipe 41 as shown in FIG. 1 or FIG. The DPF 60 includes an elongated casing. The DPF 60 includes an oxidation catalyst 61 and a soot filter 62. The oxidation catalyst 61 and the soot filter 62 are disposed inside the casing. The soot filter 62 is disposed downstream of the oxidation catalyst 61 in the direction in which the exhaust gas flows inside the casing. Exhaust gas introduced into the DPF 60 from the exhaust pipe 41 is purified by the soot filter 62 and then discharged out of the engine 100.

  The oxidation catalyst 61 is made of platinum or the like, and can promote oxidation of carbon monoxide, nitrogen monoxide and the like contained in the exhaust gas. Further, when the injector 85 performs post-injection described later, the oxidation catalyst 61 can raise the exhaust gas temperature by oxidizing the unburned fuel that has flowed with the exhaust gas.

  The soot filter 62 is composed of a wall flow type honeycomb soot filter having a plurality of cells 621 partitioned by partition walls having filterability. The soot filter 62 collects particulate matter (PM) composed of soot in the exhaust gas to filter the exhaust gas, and an oxidation reaction of PM is performed therein.

  Specifically, as shown in FIG. 3, the soot filter 62 has a configuration in which a large number of elongated cells 621 are arranged side by side. Each cell 621 is arranged such that its longitudinal direction is along the longitudinal direction of the casing of the DPF 60. Further, in one of the cells 621 adjacent to each other, the longitudinal end on the exhaust gas inlet side is closed, and on the other, the longitudinal end on the exhaust gas outlet side is closed. With this configuration, when exhaust gas passes between adjacent cells 621, PM is collected by the inner wall of the cell 621 (the cell 621 with the exhaust gas outlet side closed) and accumulated in the cell 621. The

  The amount of PM deposited on the soot filter 62 gradually increases as the engine body 10 operates, thereby increasing the exhaust gas passage resistance. If a large amount of PM accumulates on the soot filter 62, the soot filter 62 is clogged, and the exhaust gas is not smoothly discharged, which causes the engine to stop. Therefore, the PM needs to be oxidized and removed from the soot filter 62 at an appropriate timing.

  As shown in FIG. 4, the ECU 90 is electrically connected to the sensors constituting the sensor group 70 and the actuators constituting the actuator group 45. The ECU 90 can calculate parameters for controlling the operation of the actuators constituting the actuator group 45 based on information from the sensors of the sensor group 70 and control the actuators.

  The sensor group 70 includes an engine speed detection sensor 71, an intake pressure sensor 72, an intake temperature sensor 73, an exhaust pressure sensor 74, an exhaust temperature sensor 75, a differential pressure sensor 76, an oxidation catalyst temperature sensor 77, and a soot filter temperature sensor 78. Various sensors are included.

  The engine speed detection sensor 71 detects the speed (rotational speed) of the engine 100. The engine rotation speed detection sensor 71 can be configured as, for example, a crank sensor that detects rotation of a crankshaft included in the engine body 10.

  The intake pressure sensor 72 detects the pressure of the gas (EGR mixture) in the intake manifold 24. The intake air temperature sensor 73 detects the temperature of the gas in the intake manifold 24.

  The exhaust pressure sensor 74 detects the pressure of the gas (exhaust gas) in the exhaust manifold 42. The exhaust temperature sensor 75 detects the temperature of the gas in the exhaust manifold 42.

  The differential pressure sensor 76 detects a pressure difference between the upstream side of the soot filter 62 (downstream side of the oxidation catalyst 61) and the downstream side of the soot filter 62 in the DPF 60.

  The oxidation catalyst temperature sensor 77 detects the temperature near the inlet of the DPF 60 (upstream side of the oxidation catalyst 61).

  The soot filter temperature sensor 78 detects the temperature between the oxidation catalyst 61 and the soot filter 62 (upstream side of the soot filter 62).

  The actuator group 45 includes various actuators such as an injector 85, an EGR valve 52, and an intake valve 23 disposed in each combustion chamber 3.

  As shown in FIG. 4, the ECU 90 includes a calculation unit 91 configured by a CPU and the like, a storage unit 92 configured by a ROM and a RAM, and an output unit 93 configured by a connector and the like. The storage unit 92 stores software such as a control program related to reproduction of the DPF 60. The hardware and the software cooperate to operate the ECU 90 so that the remaining time calculation unit 94, the remaining time output unit 95, the PM emission amount estimation unit 96, the PM oxidation amount estimation unit 97, the regeneration capability. The calculation unit 98 and the reproduction capability output unit 99 can be operated.

  Based on the detection results output from the various sensors in the sensor group 70, the ECU 90 rotates the engine 100, the intake air flow rate, the intake air temperature, the excess air ratio (the ratio of air to fuel), the exhaust gas flow rate, and the exhaust gas temperature. Etc. can be obtained. Further, the ECU 90 can acquire the fuel injection amount of the injector 85 based on a control command to the injector 85. In this way, the ECU 90 can obtain various information regarding the state of the engine 100.

The storage unit 92 stores various programs such as the above-described control program, and also stores a plurality of control information set in advance regarding the control of the engine body 10. Examples of the control information include an output characteristic map of the engine 100, a PM emission amount map, a flow rate map of NO ₂ generated by oxidizing NO with the oxidation catalyst 61, and the like. Such control information is used to control the actuators of the actuator group 45.

  Various actuators constituting the actuator group 45 are electrically connected to the output unit 93, and various control commands and the like can be output to the actuator group 45. Further, a meter panel 112 described later is electrically connected to the output unit 93, and various information (for example, a timing calculated by the ECU 90 and requiring reset regeneration described later is required for the meter panel 112. The remaining time) can be output.

  Next, the continuous regeneration area and the forced regeneration area of the engine 100 will be described with reference to FIG. FIG. 5 is a torque diagram showing a continuous regeneration region and a forced regeneration region of the DPF 60.

  FIG. 5 is a torque diagram showing the output characteristics of the engine 100 of the present embodiment, with the engine speed on the horizontal axis and the load on the vertical axis. Here, it is preferable that the temperature of the exhaust gas is high in order to suitably regenerate the DPF 60, but the temperature of the exhaust gas is affected by the engine speed and the output torque. Therefore, from the viewpoint of DPF regeneration, as shown in FIG. 5, a region surrounded by the maximum load torque line and the horizontal and vertical axes is a curve representing the relationship between the rotational speed and torque at a predetermined exhaust gas temperature. Two regions (a continuous regeneration region and a forced regeneration region) can be considered so as to be separated by (a two-dot chain line in FIG. 5).

  The continuous regeneration region is a region in which the exhaust gas has a temperature high enough to oxidize and remove PM, and regeneration of the soot filter 62 can be realized only by normal operation.

  The forced regeneration region is a region where the exhaust gas temperature is low during normal operation and the soot filter 62 cannot be regenerated. For this reason, in the forced regeneration area, it is necessary to execute forced regeneration (assist regeneration or reset regeneration) described later for the regeneration of the soot filter 62.

  Next, control modes that the ECU 90 can take regarding DPF regeneration will be described. FIG. 6 is a diagram for explaining a playback mode that the engine 100 has. FIG. 7 is a graph showing how the DPF 60 is forcibly regenerated.

  As shown in FIG. 6, the ECU 90 roughly controls the engine 100 in two types of modes, a continuous regeneration mode and a forced regeneration mode.

  The continuous regeneration mode is a mode in which the soot filter 62 is spontaneously regenerated during the normal operation of the engine 100 on the assumption that the engine 100 is operated in the above-described continuous regeneration region. That is, in the continuous regeneration region, the exhaust gas is heated to such an extent that the amount of PM burned and removed by the soot filter 62 exceeds the amount of PM newly collected by the soot filter 62. The regeneration of the DPF 60 is naturally performed.

  The forced regeneration mode is a mode in which the PM in the soot filter 62 is forcibly burned and removed by increasing the exhaust gas temperature by controlling the operation of the engine body 10. The transition to the forced regeneration mode is performed by satisfying a predetermined condition, such as when the amount of PM deposited by the soot filter 62 exceeds a predetermined value.

  As shown in FIG. 6, the forced regeneration mode includes an assist regeneration mode, a reset regeneration mode, and a stationary regeneration mode. In the following description, the regeneration of the soot filter 62 in the continuous regeneration mode, the assist regeneration mode, the reset regeneration mode, and the stationary regeneration mode will be referred to as continuous regeneration, assist regeneration, reset regeneration, and stationary regeneration, respectively.

  In the assist regeneration mode, the opening degree of the intake valve 23 is adjusted, and the injection timing of the injector 85 is set to after-injection, thereby increasing the exhaust gas temperature and realizing regeneration of the soot filter 62 by forced combustion of PM. be able to.

  FIG. 7 is a graph showing how the forced regeneration including the assist regeneration is performed when the engine 100 is operated in the above-described forced regeneration region. In the graph of FIG. 7, the transition of the PM deposition amount is shown with the time as the horizontal axis and the PM deposition amount per unit volume of the soot filter 62 as the vertical axis. As shown in the example of FIG. 7, when the PM accumulation amount in the soot filter 62 becomes equal to or greater than a predetermined threshold value M <b> 1, assist regeneration is performed by a control command from the ECU 90. The predetermined PM deposition amount value M2 shown in the graph is determined as the upper limit value of the PM deposition amount that allows DPF regeneration without problems. If the PM deposition amount exceeds this value M2, there is a risk that PM will burn violently during DPF regeneration and the soot filter 62 will be damaged.

In the above-described continuous regeneration and assist regeneration, the temperature in the DPF 60 is controlled to be relatively low (250 ° C. to 500 ° C.) as compared with reset regeneration and stationary regeneration. At this time, as shown in FIG. 3, NO (nitrogen monoxide) contained in the exhaust gas is oxidized to NO ₂ (nitrogen dioxide) by the promoting action of the oxidation catalyst 61. The NO ₂ provides O (oxygen atoms) for the oxidation of PM in the soot filter 62.

  The reset regeneration is performed when the accumulated amount of PM still remains beyond a predetermined amount even when the assist regeneration is performed for a predetermined time, or when the accumulated operation time of the engine becomes a predetermined time or more. On the left side of FIG. 7, the assist regeneration is first performed for a predetermined time because the PM accumulation amount becomes equal to or greater than the predetermined threshold M1, but the reset regeneration is performed because the PM accumulation amount did not fall below the threshold M1. An example of what was done is shown.

  In the reset regeneration mode, the ECU 90 performs control (post-injection) to inject fuel into the combustion chamber 3 after the combustion process, in addition to the control in the assist regeneration mode, so that the fuel is combusted in the oxidation catalyst 61, The exhaust gas temperature in the soot filter 62 can be further increased. As a result, the PM deposited on the soot filter 62 can be forcibly burned and removed.

  In the reset regeneration, the exhaust gas temperature becomes considerably high. Therefore, in the engine 100 of the present embodiment, the execution of the reset regeneration is configured to be started by an operator's operation. Specifically, when reset regeneration is necessary, the ECU 90 outputs an instruction to the tractor 110 to display that reset regeneration is necessary.

  Next, the meter panel (display unit) 112 provided in the tractor 110 will be described. FIG. 8 is a front view of the meter panel 112 as seen from the cockpit of the tractor 110.

  As shown in FIG. 1, the tractor 110 is provided with a driving unit 111 including a cockpit, an operation tool, and the like for an operator to drive. The driving unit 111 includes a meter panel 112 that can display information regarding the operation of the tractor 110 and the operation of the engine 100. As shown in FIG. 8, the meter panel 112 is configured as a driving operation display device, and an engine tachometer that indicates the number of revolutions of the engine 100 with a pointer is arranged in a display area arranged in the center thereof.

  As shown in FIG. 8, the meter panel 112 includes a regeneration lamp 113. When a signal indicating that reset regeneration is necessary is received from the ECU 90 of the engine 100, the meter panel 112 causes the regeneration lamp 113 to blink. Thereby, the operator can know that the reset regeneration is necessary.

  As shown in FIG. 8, the operating unit 111 includes a regeneration switch 114 disposed in the vicinity of the meter panel 112. When the operator presses the regeneration switch 114 for a predetermined time, the ECU 90 can be shifted to the reset regeneration mode and reset regeneration can be executed. In order to prevent the operator from touching the playback switch 114 with any momentum and unintentionally executing the reset playback, a so-called long press operation of the playback switch 114 is necessary to perform the reset playback. It is the composition.

  If the accumulated amount of PM still remains beyond the predetermined threshold value M1 even after executing reset regeneration for a predetermined time, the ECU 90 outputs a signal indicating that stationary regeneration is necessary. When it is necessary to execute stationary regeneration, the instrument panel 112 causes the regeneration lamp 113 and the display lamp 116 shown in FIG. 8 to blink at a high speed in response to an instruction from the ECU 90 and also sounds an alarm buzzer (not shown). To inform. When a specific transition condition such as the operator parking the tractor 110 is established, the ECU 90 shifts to the stationary regeneration mode and performs stationary regeneration.

  In the stationary regeneration mode, the exhaust gas temperature can be further increased by performing control for maintaining the rotational speed of the engine 100 at a predetermined rotational speed higher than normal in addition to the control of the reset regeneration mode. As a result, the stationary regeneration mode can remove PM in the soot filter 62 under better conditions than the reset regeneration mode.

In the reset regeneration and the stationary regeneration, the fuel that has flowed into the DPF 60 by the post-injection burns in the oxidation catalyst 61, so that the exhaust gas temperature is relatively high (500 ° C.˜ (About 700 ° C.). At this time, the oxidation catalyst 61 does not generate an oxidation reaction as shown in FIG. 3, and O ₂ (oxygen) is directly provided for the combustion of PM.

  Next, the relationship between various regeneration modes, the temperature of exhaust gas flowing through the DPF 60, and the operation of the tractor 110 will be described.

  As shown in FIG. 6, when the ECU 90 is in the continuous regeneration mode or the assist regeneration mode, the exhaust gas flowing through the DPF 60 is at a relatively low temperature. On the other hand, when the ECU 90 is in the reset regeneration mode or the stationary regeneration mode, the exhaust gas flowing through the DPF 60 is controlled to have a relatively high temperature by performing the post injection described above.

  Further, when the ECU 90 is in the continuous regeneration mode, the assist regeneration mode, or the reset regeneration mode, the operation by the tractor 110 can be performed without any problem in principle. On the other hand, when the ECU 90 is in the stationary regeneration mode, the work by the tractor 110 cannot be substantially performed because of the control of operating the engine 100 at a predetermined rotational speed.

  Therefore, from the viewpoint of preventing the work on the tractor 110 from being interrupted and ensuring convenience, the stationary reproduction mode is avoided and the DPF is used in another reproduction mode (continuous reproduction mode, assist reproduction mode, or reset reproduction mode). It is preferable to perform regeneration. However, even though it is possible to work with the tractor 110, it may not always be appropriate to perform the DPF regeneration in the reset regeneration mode in which the exhaust gas becomes high temperature depending on the work place. Therefore, for example, when the DPF regeneration in the reset regeneration mode becomes necessary while working with the tractor 110 in a place where high temperature exhaust gas is disliked, the operator interrupts the work early and leaves the place. After moving the tractor 110 as described above, it is necessary to execute the DPF regeneration in the reset regeneration mode by pressing the regeneration switch 114 described above. In this case, the operator is forced to change the work schedule suddenly, and the work efficiency is greatly reduced.

  On the other hand, after the operator depresses the operation of pressing the regeneration switch 114, the work in the place where high temperature is disliked is completed, and after moving to another place, the regeneration switch 114 is pressed to perform DPF regeneration in the reset regeneration mode. It is also possible. However, since PM accumulates further during work, there is a limit to the postponement of reset regeneration. In extreme cases, it is necessary to shift to the stationary regeneration mode in which the use of the tractor 110 is greatly restricted, There was also a risk that it would be necessary to perform proper maintenance.

  In this regard, the engine 100 according to the present embodiment is configured such that the ECU 90 can predict the remaining time until the time when reset regeneration is necessary by calculation. Then, the ECU 90 can output the obtained remaining time so that it can be displayed on the tractor 110 side.

  When described in detail with reference to FIG. 4, the ECU 90 includes the remaining time calculation unit 94 and the remaining time output unit 95 as described above. The remaining time calculation unit 94 calculates the remaining time until the PM accumulation amount reaches a predetermined threshold M1 by calculating the increase amount per unit time of the PM accumulation amount accumulated in the soot filter 62. Can be predicted in advance. The remaining time output unit 95 outputs the remaining time calculated by the remaining time calculating unit 94 to a device on the tractor 110 side (in the present embodiment, the meter panel 112).

  By displaying the remaining time on the meter panel 112, the operator can easily grasp the timing when the reset regeneration of the DPF 60 is necessary. As a result, the operator can plan the order of operations in advance so that reset regeneration is not necessary during work in a place where reset regeneration is inappropriate. As a result, work efficiency can be improved.

  Next, the estimation of the PM accumulation amount will be described. FIG. 9 is a diagram for explaining the calculation of the PM accumulation amount performed by the ECU 90.

  As shown in FIG. 3, the ECU 90 of this embodiment includes a PM emission amount estimation unit (emission amount calculation unit) 94 and a PM oxidation amount estimation unit (oxidation amount calculation unit) 95.

  Specifically, with reference to FIG. 9, the PM emission amount estimation unit 96 acquires operation information such as the rotational speed of the engine 100, the fuel injection amount, the intake flow rate, and the exhaust gas flow rate from the sensor group 70 and the like, The PM discharge speed (discharge amount per unit time) with respect to the current operating state of the engine 100 is estimated by calculation. For calculating the PM discharge speed, an unillustrated PM discharge amount map or the like stored in advance in the storage unit 92 is used.

The PM oxidation amount estimation unit 97 can estimate the PM oxidation rate (oxidation amount per unit time) by NO ₂ and the PM oxidation rate by O ₂ by calculation.

More specifically, the PM oxidation amount estimation unit 97 acquires information such as the temperature in the oxidation catalyst 61 and the exhaust gas flow rate from the sensor group 70, and estimates the flow rate of NO ₂ supplied to the soot filter 62. Note that the calculation of the flow rate of NO _2, an unillustrated NO ₂ flow map is used. The PM oxidation amount estimation unit 97 estimates the PM oxidation rate based on the estimated NO ₂ flow rate and the temperature of the soot filter 62 acquired from the soot filter temperature sensor 78. In the following description, the oxidation rate of PM by NO ₂ is referred to as a first PM oxidation rate.

Further, the PM oxidation amount estimation unit 97 obtains information such as the intake flow rate, the rotation speed, the fuel injection amount, the exhaust gas recirculation amount from the sensor group 70 and the like, and calculates the excess air ratio so as to be included in the exhaust gas. Estimate the amount of O ₂ Then, the PM oxidation amount estimation unit 97 estimates the PM oxidation rate based on the estimated amount of O ₂ in the exhaust gas and the temperature of the soot filter 62 acquired from the soot filter temperature sensor 78. In the following description, the oxidation rate of PM by O ₂ is referred to as a second PM oxidation rate.

As shown in FIG. 9, the ECU 90, based on the PM emission rate estimated by the PM emission amount estimation unit 96, the NO ₂ oxidation rate (first PM oxidation rate) and O ₂ estimated by the PM oxidation amount estimation unit 97. The PM deposition rate on the soot filter 62 can be obtained by subtracting the oxidation rate due to (second PM oxidation rate). Then, the ECU 90 obtains the PM accumulation amount by integrating the obtained PM deposition rate with time, and obtains the PM accumulation amount per unit volume by dividing the accumulation amount by the volume of the soot filter 62. In the following, the method for estimating the PM deposition amount based on the chemical reaction model as described above may be referred to as “C method”.

  Further, as described above, when PM accumulates on the soot filter 62, the exhaust gas passage resistance increases accordingly. By utilizing this fact, the pressure difference between the upstream side and the downstream side of the soot filter 62 can be detected by the differential pressure sensor 76, and the amount of accumulated PM can be obtained based on the detection result. Hereinafter, such a method for estimating the amount of accumulated PM based on the pressure difference may be referred to as a “P method”.

  However, the amount of PM deposited by the above-described P method is likely to have a relatively large error due to uneven PM deposition on the soot filter 62 or the like. Therefore, in the engine 100 of the present embodiment, the PM accumulation amount is estimated mainly by the C method, and the P method is used as a preliminary role when estimation by the C method is difficult.

  The ECU 90 repeats the estimation of the PM accumulation amount as described above at predetermined time intervals, and stores the result in the storage unit 92. Thereby, the ECU 90 can obtain a time transition of the PM accumulation amount as shown in FIG.

  Next, calculation of the remaining time until the timing at which reset regeneration is necessary in the engine 100 of the present embodiment will be described. FIG. 10A is a diagram illustrating calculation of the time T until the timing at which forced regeneration is necessary. FIG. 10B is a diagram for explaining the process of determining the increasing / decreasing tendency of the PM accumulation amount.

  As shown in FIG. 10A, the time (first time) T until the timing at which reset regeneration is required is a threshold value that is predetermined as an increasing tendency of the PM deposition amount and a deposition amount that requires reset regeneration. And can be calculated based on M1. Specifically, as shown in the calculation formula shown in FIG. 10A, the PM deposition amount is equal to the predetermined threshold value using the PM deposition amount at the current time t2 and the time t1 that is a predetermined time before the current time. The time t3 when reaching M1 can be calculated. That is, in the present embodiment, the PM accumulation amount shown in FIG. 10A is assumed to change according to a linear function after the current time t2, and the time t3 at which the PM accumulation amount reaches the threshold value M1 is estimated. By subtracting the current time t2 from this time t3, it is possible to obtain the time (first time) until the timing when the reset regeneration is necessary.

  Strictly speaking, the threshold value M1 is a PM accumulation amount that requires assist regeneration instead of reset regeneration. However, as described above, the condition for performing the reset regeneration is that the PM accumulation amount reaches the threshold value M1, and the PM accumulation amount does not fall below the threshold value M1 even if the assist regeneration is performed for a predetermined time (first). conditions). Accordingly, it can be said that there is a high possibility that the reset regeneration is performed at a timing not far from the timing at which the PM accumulation amount reaches the threshold value M1.

Here, it is preferable that the time T _i from the time t1 to the current time t2 is appropriately determined so as not to be too short. This is because increasing or decreasing trend of the PM deposit amount (in other words, work performed by the tractor 110, etc.) operation state of the engine 100 to vary significantly depending, shortening the time T _i, the predicted result is excessive according to the most recent work not This is because it may become stable.

Further, in the engine 100 of the present embodiment, even if the PM accumulation amount does not reach the threshold value M1, the accumulated operation time of the engine 100 since the previous reset regeneration or stationary regeneration has reached a predetermined time. In such a case, it is determined that it is necessary to perform reset reproduction (second condition). On the right side of FIG. 7, reset regeneration for the accumulated operating time of the engine 100 from the reset regeneration is performed last time exceeds a predetermined time T _A is shown to have been carried out again. The ECU 90 can calculate the time (second time) until the timing when the reset regeneration is necessary by calculating the time that the engine 100 has been operated since the previous reset regeneration or stationary regeneration.

  As described above, in the engine 100 of the present embodiment, it is determined that the reset regeneration is necessary when any one of the two types of conditions is satisfied. Therefore, the ECU 90 determines the remaining time (first time) until the timing at which reset regeneration is necessary for each of the condition based on the PM accumulation amount (first condition) and the condition based on the accumulated operation time (second condition). And second time). Then, the ECU 90 compares the two times, and adopts the shorter one as the remaining time until the timing when the reset regeneration is necessary.

  In order to inform the operator of the remaining time thus calculated, a liquid crystal panel 115 is arranged on the meter panel 112 as shown in the figure. On the liquid crystal panel 115, the remaining time until the timing at which reset regeneration is necessary can be displayed as, for example, “about 2 hours until forced regeneration”.

  However, how to display the remaining time is not particularly limited, and for example, a graphical display imitating an instrument or the like may be performed. Further, when the remaining time is sufficient, the above display is not performed, and the display may be performed only when the remaining time is less than a predetermined time.

  The remaining time calculation unit 94 repeatedly performs prediction (calculation) of the remaining time up to the timing at which reset regeneration is necessary at an appropriate time interval, and the remaining time output unit 95 outputs the latest prediction result of the remaining time. To do. As a result, the remaining time displayed on the meter panel 112 is updated as needed. Therefore, based on the displayed prediction result, for example, the reset regeneration is likely to be required after several hours, so that the work in a place where high temperature exhaust gas is disliked is completed now. It is possible to work on the tractor 110 with an appropriate plan.

  Further, as shown in FIG. 3, the ECU 90 has a regeneration capability calculation unit (deposition amount increase / decrease trend calculation unit) 98 that determines the DPF regeneration capability in the current operating state of the engine 100, and a regeneration capability that outputs the DPF regeneration capability. An output unit (deposition amount increase / decrease trend output unit) 99. In this specification, “DPF regeneration capability” indicates whether the operating state of the engine 100 is advantageous or disadvantageous for regeneration of the DPF 60, and the PM deposition amount time transition curve shown in FIG. It corresponds to the inclination. That is, when the PM deposition amount decreases with time, it can be said that the regeneration capacity is high, and when the PM deposition amount increases, it can be said that the regeneration capacity is low.

  As shown in FIG. 10B, the regeneration capacity calculation unit 98 determines the DPF regeneration capacity in the operating state of the engine 100 at the present time by calculation based on the change in the PM accumulation amount per unit time. Specifically, the regeneration capacity calculation unit 98 uses the PM accumulation amount (m1, m2) at the current time t2 and the time t1 a predetermined time before the present to change the PM accumulation amount per unit time. Calculate (PM deposition rate).

  When the value of the PM deposition rate is 0 or less (that is, when the amount of PM deposition has not increased), the DPF regeneration capability in the current operating state of the engine 100 (work performed by the tractor 110) is high. It is determined. If the value of the PM deposition rate is greater than 0 and less than or equal to the predetermined threshold k, it is determined that the DPF regeneration capability is moderate. When the PM deposition rate value is greater than k, it is determined that the DPF regeneration capability is low.

  The ECU 90 (reproduction capability output unit 99) outputs a signal including the DPF regeneration capability level determined by the regeneration capability calculation unit 98 to the meter panel 112 via the output unit 93. When a signal is input to the meter panel 112, the meter panel 112 displays the DPF regeneration capability level on the liquid crystal panel 115, for example, “Level: Medium” as shown in FIG.

  The regeneration capability calculation unit 98 repeatedly calculates the DPF regeneration capability at an appropriate time interval, and the regeneration capability output unit 99 outputs the latest calculation result of the DPF regeneration capability. As a result, the playback capability level displayed on the meter panel 112 is updated as needed. Therefore, the operator can grasp whether the work currently performed by the tractor 110 is advantageous or disadvantageous for the regeneration of the DPF 60 by looking at the displayed regeneration ability level. Thus, for example, when there is a situation such as a work schedule, the operator can perform the work while paying attention to postponing (or moving forward) the timing at which the reset regeneration is necessary. As a result, the timing at which reset regeneration is required can be adjusted to a certain degree of accuracy, so that the convenience of the engine 100 and the tractor 110 can be enhanced.

  In the engine 100 of the present embodiment, the DPF regeneration capability is displayed at three levels (three levels) of high, medium, and low. However, the present invention is not limited to this and is displayed at four or more levels. Also good.

  As described above, the engine 100 of the present embodiment is provided with the DPF 60 that purifies the exhaust gas. The engine 100 has a plurality of regeneration modes in which the PM collected and deposited in the DPF 60 is removed by oxidizing. The engine 100 includes an engine main body 10 and an ECU 90. A DPF 60 is disposed in the engine body 10. The ECU 90 can be controlled to shift to a plurality of regeneration modes for removing PM in the DPF 60. The plurality of regeneration modes include at least a reset regeneration mode for forcibly increasing the amount of PM to be oxidized. The ECU 90 includes a remaining time calculation unit 94 and a remaining time output unit 95. The remaining time calculation unit 94 is a timing at which regeneration of the DPF 60 in the reset regeneration mode is required based on at least one of the accumulated amount of PM accumulated in the DPF 60 and the operation time of the engine body 10 (forced regeneration necessary timing). Calculate the remaining time until. The remaining time output unit 95 outputs the remaining time calculated by the remaining time calculation unit 94.

  Thereby, the operator can grasp the remaining time until the timing at which reset regeneration of the DPF 60 in the engine 100 is required. Therefore, the operator can avoid operating the engine in a place that is not suitable for reset regeneration during a time period when reset regeneration is required, or can complete reset regeneration before operating the engine in that place. In this way, the operator can reasonably plan work using the engine 100 in relation to the timing at which reset regeneration is necessary.

  Further, in the engine 100 of the present embodiment, the ECU 90 further includes a PM emission amount estimation unit 96 and a PM oxidation amount estimation unit 97. The PM emission amount estimation unit 96 calculates an emission amount that is the amount of PM discharged from the engine body 10 to the DPF 60. The PM oxidation amount estimation unit 97 calculates an oxidation amount that is the amount of PM oxidized by the DPF 60. The ECU 90 calculates the PM accumulation amount in the DPF 60 using the emission amount calculated by the PM emission amount estimation unit 96 and the oxidation amount calculated by the PM oxidation amount estimation unit 97.

  As a result, the amount of PM accumulated in the DPF 60 can be accurately predicted, so that the remaining time until the timing at which the engine 100 needs to be reset can be calculated more accurately.

  In the engine 100 of the present embodiment, the DPF 60 includes a soot filter 62 and a differential pressure sensor 76. The soot filter 62 collects PM. The differential pressure sensor 76 detects a pressure difference between exhaust gas upstream and downstream of the soot filter 62. The ECU 90 calculates the PM accumulation amount in the DPF 60 based on the detection result of the differential pressure sensor 76.

  As a result, the amount of PM deposited in the DPF 60 can be accurately predicted.

  In the engine 100 of the present embodiment, the ECU 90 includes at least one of a first condition in which the PM accumulation amount in the DPF 60 is equal to or greater than a predetermined threshold and a second condition in which the operation time of the engine body 10 is equal to or greater than a predetermined time. If any one of them is satisfied, it is determined that regeneration of the DPF 60 in the reset regeneration mode is necessary. The remaining time calculation unit 94 includes a first time that is a remaining time until the forced regeneration necessary timing related to the first condition, and a second time that is a remaining time until the forced regeneration necessary timing related to the second condition. Of these, the remaining time is defined as the remaining time.

  As a result, in the engine 100 having the conditions for shifting to a plurality of reset regeneration modes, the timing at which reset regeneration is required can be output more accurately, so that the operator can plan the operation of the engine 100 more appropriately. it can.

  In the engine 100 of the present embodiment, the ECU 90 further includes a regeneration capability calculation unit 98 and a regeneration capability output unit 99. Based on the operating state of the engine body 10, the regeneration capacity calculation unit 98 calculates an increasing / decreasing tendency of the PM accumulation amount in the DPF 60. The reproduction capability output unit 99 outputs the increase / decrease tendency calculated by the reproduction capability calculation unit 98.

  Thus, the operator can grasp whether the work currently being performed using the engine 100 is to increase or decrease the amount of accumulated PM. Therefore, the operator defers (or puts forward) the timing of reset regeneration in the engine 100 by operating the engine in an operating state that is advantageous (or disadvantageous) with respect to DPF regeneration according to circumstances such as the work schedule. )can do.

  The tractor 110 according to the present embodiment includes an engine 100 and a meter panel 112. The meter panel 112 can display the remaining time output from the remaining time output unit 95.

  Thereby, the operator of the tractor 110 can easily confirm the remaining time until the timing when the reset regeneration is necessary, based on the display on the meter panel 112. Therefore, the operator can rationally plan the operation using the tractor 110 according to the remaining time until the timing when the reset regeneration is necessary. As a result, the convenience of the tractor 110 can be improved.

  Further, in the tractor 110 of the present embodiment, the meter panel 112 can display the increase / decrease tendency output from the playback capability output unit 99.

  As a result, the operator of the tractor 110 can easily confirm whether the work currently being performed is to increase or decrease the amount of accumulated PM based on the display on the meter panel 112. Therefore, the operator can postpone (or advance) the timing at which the reset regeneration is necessary by performing an operation that is advantageous (or disadvantageous) with respect to the regeneration of the DPF 60 according to circumstances such as the work schedule. It becomes easy. As a result, the convenience of the tractor 110 can be improved.

  The preferred embodiment of the present invention has been described above, but the above configuration can be modified as follows, for example.

  The present invention is not limited to the engine 100 including the exhaust valve 43, and can be applied to an engine not provided with the exhaust valve 43.

  In the above embodiment, only the remaining time until the timing at which the reset playback is required is displayed on the meter panel 112, but the remaining time until shifting to each of the assist playback mode, the reset playback mode, and the stationary playback mode is displayed. You may comprise so that it may calculate and display.

  The transition conditions for the assist regeneration mode, the reset regeneration mode, and the stationary regeneration mode are not limited to the above-described examples, and can be changed as appropriate.

  The remaining time and the reproduction capability level are not limited to the meter panel 112 but can be displayed on another appropriate display device.

  If the ECU 90 determines that the reset regeneration is necessary, the ECU 90 can be configured to immediately shift to the reset regeneration mode without waiting for the operation of the regeneration switch 114.

  The present invention can be applied not only to a work vehicle as an agricultural machine such as the tractor 110 but also to a work vehicle as a construction machine such as a skid steer loader. In addition, the present invention is not limited to work vehicles, and can also be applied to engines mounted on various machines such as ships, automobiles, and generators.

10 Engine body 60 DPF (Exhaust gas purification device)
62 soot filter 76 differential pressure sensor 90 ECU (control unit)
94 Remaining time calculation part 95 Remaining time output part 96 PM emission amount estimation part (discharge amount calculation part)
97 PM oxidation amount estimation unit (oxidation amount calculation unit)
98 Reproduction capacity calculator (change / increase trend calculator)
99 Playback capacity output section (increase / decrease trend output section)
100 engine 110 tractor (work vehicle)
112 Meter panel (display section)

Claims (7)

An exhaust gas purification device for purifying exhaust gas is provided, and an engine having a plurality of regeneration modes for removing particulate matter collected and deposited in the exhaust gas purification device by oxidizing,
An engine body in which the exhaust gas purifying device is disposed;
A control unit capable of controlling transition to a plurality of regeneration modes for removing particulate matter in the exhaust gas purification device;
With
The plurality of regeneration modes include at least a forced regeneration mode for forcibly increasing the amount of the particulate matter to be oxidized,
The controller is
Forced regeneration is required, which is the timing at which regeneration of the exhaust gas purification device in the forced regeneration mode is required based on at least one of the accumulated amount of the particulate matter in the exhaust gas purification device and the operation time of the engine body A remaining time calculation unit for calculating the remaining time until the timing;
A remaining time output unit that outputs the remaining time calculated by the remaining time calculating unit;
An engine comprising: The engine according to claim 1,
The controller is
An emission amount calculation unit for calculating an emission amount that is an amount of the particulate matter discharged from the engine body to the exhaust gas purification device;
An oxidation amount calculation unit for calculating an oxidation amount which is an amount of the particulate matter oxidized by the exhaust gas purification device;
Further comprising
The control unit uses the emission amount calculated by the emission amount calculation unit and the oxidation amount calculated by the oxidation amount calculation unit to deposit the particulate matter in the exhaust gas purification apparatus. An engine characterized by calculating The engine according to claim 1 or 2,
The exhaust gas purification device includes:
A soot filter for collecting the particulate matter;
A differential pressure sensor for detecting a pressure difference between the exhaust gas upstream and downstream of the soot filter;
With
The engine, wherein the control unit calculates the accumulation amount of the particulate matter in the exhaust gas purification device based on a detection result of the differential pressure sensor. The engine according to any one of claims 1 to 3,
The control unit includes at least one of a first condition in which the accumulation amount of the particulate matter in the exhaust gas purification device is equal to or greater than a predetermined threshold and a second condition in which the operation time of the engine body is equal to or greater than a predetermined time. If this is satisfied, it is determined that regeneration of the exhaust gas purification device in the forced regeneration mode is necessary,
The remaining time calculation unit includes: a first time that is a remaining time until the forced regeneration necessary timing related to the first condition; and a second time that is a remaining time to the forced regeneration necessary timing related to the second condition. An engine characterized in that the shorter time is the remaining time. The engine according to any one of claims 1 to 4, wherein
The controller is
Based on the operating state of the engine body, a deposit amount increase / decrease trend calculation unit for calculating the increase / decrease trend of the particulate matter in the exhaust gas purification device;
Increase / decrease trend output unit for outputting the increase / decrease trend calculated by the accumulation amount increase / decrease trend calculation unit,
An engine further comprising: An engine according to any one of claims 1 to 5;
A display unit capable of displaying the remaining time output from the remaining time output unit;
A work vehicle comprising: An engine according to claim 5;
A display unit capable of displaying the increase / decrease trend output from the increase / decrease trend output unit;
A work vehicle comprising:

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