JP2013113142A - Work machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To allow DPF regeneration to be performed without affecting work.SOLUTION: A work machine includes: first temperature raising means for raising the exhaust temperature inside an exhaust emission control device 20 toward a first target temperature when the accumulation amount of particulate matter accumulated on a filter 21 of the exhaust emission control device 20 exceeds a predetermined value; first combustion condition determination means 41 for determining whether the exhaust temperature has reached the first target temperature or not after the start of temperature raising by the first temperature raising means 40; temperature raising confirming means 42 for confirming whether temperature raising for raising the exhaust temperature above the first target temperature should be done or not after determining that the exhaust temperature has reached the first target temperature by the first combustion condition determination means 41; and second temperature raising means 43 for raising the exhaust temperature to a second target temperature which is higher than the first target temperature and prompts combustion of the particulate matter when temperature raising is confirmed to be performed by the temperature raising confirmation means 42.

Description

  The present invention relates to a work machine including a diesel particulate filter (DPF).

  Generally, a diesel engine is provided with a diesel particulate filter (DPF) that collects particulate matter (particulate master) contained in exhaust gas. The DPF collects particulate matter contained in exhaust gas from the diesel engine, and the collected particulate matter gradually accumulates. For this reason, in a vehicle equipped with a DPF, a DPF regeneration technique has been developed in which the exhaust temperature of a diesel engine is increased, the particulate matter deposited on the DPF is burned, and the particulate matter deposited on the DPF is reduced. .

Development of DPF regeneration technology is carried out on large trucks prior to working machines such as agricultural machinery and construction machinery equipped with diesel engines. Patent Document 1 discloses the technology for regenerating truck DPFs. .
Patent Document 1 urges the driver to regenerate the DPF when the accumulated amount of particulates in the DPF is equal to or higher than a threshold that requires regeneration and the temperature of the DPF is equal to or higher than the regeneration start suitable temperature. This is a technique in which DPF regeneration is performed when the driver presses a regeneration switch provided in the driver's seat.

  That is, in the technique of Patent Document 1, since the DPF regeneration may not be completed in some cases when the load fluctuation during traveling is severe, the driver is notified of a suitable time for the regeneration of the DPF, and then the driver Can determine the driving situation and manually instruct the regeneration of the DPF.

JP 2005-155444 A

  There is also a demand for an agricultural machine or a construction machine working machine to judge the driving condition (traveling condition) and instruct the regeneration of the DPF. However, although the working machine travels in the same manner as the above-described truck, the driving situation is completely different from that of the truck. For example, an agricultural machine such as a tractor often travels while performing work in a field. If regeneration of the DPF is automatically started during work in the field, a high temperature due to regeneration of the DPF is applied to the crop or the like. Exhaust gas may be hit and the crop may be damaged by the exhaust gas from the regeneration of the DPF. For this reason, during the work of the tractor, the operator who operates the tractor must always pay attention to the regeneration of the DPF, and the work by the tractor does not proceed smoothly, which may affect the work by the tractor.

  Accordingly, an object of the present invention is to provide a work machine that can regenerate the DPF without affecting the work performed by the work machine.

In order to achieve the above object, the present invention has taken the following measures.
According to the working machine according to claim 1, the exhaust gas purification device including a filter that collects particulate matter contained in the exhaust gas exhausted from the diesel engine, and the particles deposited on the filter of the exhaust gas purification device A first temperature raising means for raising the temperature of the exhaust gas in the exhaust gas purification device toward the first target temperature when the amount of deposit of the particulate matter is equal to or greater than a predetermined value, and after the temperature raising start by the first temperature raising means After determining that the exhaust temperature has reached the first target temperature by first combustion condition determining means for determining whether the exhaust temperature has reached the first target temperature and the first combustion condition determining means. Furthermore, when it is confirmed that the exhaust temperature is increased to a temperature higher than the first target temperature and whether the temperature increase is confirmed by the temperature increase confirmation unit for confirming whether or not the temperature increase is performed. The exhaust temperature is the first Characterized in that it includes a second temperature increase device for raising the temperature towards the second target temperature combustion of high and particulate matter than target temperature is promoted, the.

  According to the work machine according to claim 2, the second combustion condition determining means for determining whether or not the exhaust temperature is lower than the first target temperature after starting the temperature increase by the second temperature increasing means, the exhaust temperature If the temperature is not lower than the first target temperature, the temperature raising by the second temperature raising means is continued, and if the exhaust temperature is lower than the first target temperature, the temperature raising continuation stopping means for stopping the temperature raising by the second temperature raising means, It is characterized by having.

  According to the work machine according to claim 3, an off-condition notifying unit for notifying that the exhaust gas temperature is lower than the first target temperature after the second temperature raising unit starts to raise the temperature, and the second temperature raising unit. And a temperature raising guide means for urging the temperature of the exhaust gas to rise by increasing the engine speed of the diesel engine when the temperature is lower than the first target temperature after the temperature raising starts by the means. Features.

  According to a work machine according to a fourth aspect of the present invention, the temperature increase confirmation unit determines that the confirmation is made when a regeneration confirmation switch installed around the driver's seat is operated.

  According to claim 1, after the exhaust temperature is raised to the first target temperature when the accumulation amount becomes a predetermined value or more, the particles are further raised to the second target temperature higher than the first target temperature. When burning particulate matter, it is possible to raise the exhaust temperature after confirming the temperature rise.For example, check the temperature rise when there is no hindrance to the work by looking at the interval between work by the work equipment. Thus, the regeneration of the DPF (combusting the particulate matter deposited on the filter) can be performed freely, and the DPF can be easily regenerated without affecting the work performed by the work machine. In particular, since control is performed to raise the exhaust temperature to the first target temperature and then to the second target temperature, after confirming the temperature rise, the exhaust temperature is quickly raised to a temperature range where the particulate matter is combusted. Thus, the particulate matter can be combusted, and there is no time lag between the temperature rise confirmation by the worker and the regeneration of the DPF, and the operator's intention to raise the temperature can be reflected immediately.

  According to the second aspect, when the exhaust gas temperature does not quickly rise to the second target temperature and becomes lower than the first target temperature after the temperature raising starts by the second temperature raising means, the temperature raising by the second temperature raising means is stopped. Thus, the temperature can be newly switched to the temperature raising by the first temperature raising means, and the temperature raising by the second temperature raising means can be performed again when the exhaust gas temperature becomes equal to or higher than the first target temperature. That is, after the start of temperature increase by the second temperature increase means, for example, if the exhaust temperature cannot be increased quickly due to load fluctuations of the work implement, a retry process can be performed to increase the exhaust temperature. .

According to the third aspect, the operator (operator) who operates the work machine can know that the exhaust temperature is lower than the first target temperature, and the exhaust temperature can be increased by manually increasing the engine speed. Can be compensated for.
According to the fourth aspect, the operator can easily press the regeneration confirmation switch while operating the working machine, and the temperature rise can be easily confirmed.

It is a figure which shows the structure of the exhaust gas purification apparatus in 1st Embodiment. It is a figure which shows transition (change) of exhaust temperature. It is a flowchart which shows operation | movement of the reproduction | regeneration mode in 1st Embodiment. It is a figure which shows the structure of the exhaust gas purification apparatus in 2nd Embodiment. It is a figure which shows the structure of the exhaust gas purification apparatus in 3rd Embodiment. It is a flowchart which shows operation | movement of the reproduction | regeneration mode in 3rd Embodiment. It is a figure which shows the structure of the exhaust gas purification apparatus in the 1st modification of 3rd Embodiment. It is a flowchart which shows operation | movement of the reproduction | regeneration mode in the 1st modification of 3rd Embodiment. It is a flowchart which shows operation | movement of the reproduction | regeneration mode in the 2nd modification of 3rd Embodiment. It is a figure which shows the structure of the exhaust gas purification apparatus in 3rd Embodiment. It is the whole tractor side view.

Embodiments of the present invention will be described below with reference to the drawings.
[First embodiment]
The work machine of the present invention includes a diesel particulate filter (DPF) and a means for burning and removing particulate matter deposited on the DPF. Such a working machine is an agricultural machine such as a tractor or a combiner and a construction machine such as a backhoe or a compact truck loader (CTL), which can perform a work such as a farm work or a construction work. To do.

  As shown in FIG. 11, the tractor 1 is configured by mounting a diesel engine 3, a transmission device 4, and the like on a traveling vehicle body 2 having front and rear wheels. A three-point link mechanism 5 is provided at the rear portion of the traveling vehicle body 2 so as to be movable up and down. Various working devices 6 such as a tillage device, a fertilizer application device, and a harvesting device are detachable from the three-point link mechanism 5. The power from the diesel engine 3 is transmitted to the work device 6 via the PTO shaft. In addition, an independently mounted cabin 7 is provided behind the diesel engine 3, and a driver's seat 8 is provided in the cabin 7.

FIG. 1 shows the structure of the exhaust system in the diesel engine 3. Normally, the diesel engine 3 is often a multi-cylinder engine having a plurality of cylinders (cylinders), but FIG. 1 shows one of them.
Hereinafter, the exhaust system of the diesel engine 3 will be described in detail.
As shown in FIG. 1, an intake port 11, which is an opening for introducing air into the cylinder 10, is formed in an upper portion of a cylinder 10 of a diesel engine (hereinafter referred to as an engine) 3 and after combustion. An exhaust port 12 that is an opening for discharging gas (combustion gas) from the cylinder 10 is formed. Further, an intake valve 13 for opening and closing the intake port 11 and an exhaust valve 14 for opening and closing the exhaust port 12 are provided at the upper portion of the cylinder 10.

  The intake port 11 is connected to a tubular intake manifold 15 that serves as a flow path for air introduced into the cylinder 10. The exhaust port 12 is connected to a tubular exhaust manifold 16 serving as a flow path for combustion gas discharged from the cylinder 10. A silencer 17 for reducing exhaust noise is provided at the end of the exhaust manifold 16, and the combustion gas passes through the silencer 17 and is discharged to the outside.

  In the exhaust manifold 16, an exhaust gas purification device 20 is provided between the exhaust port 12 and the silencer 17. The exhaust gas purification device 20 collects and purifies particulate matter contained in the exhaust gas that passes through. That is, the combustion gas discharged from the cylinder 10 through the exhaust port 12 becomes exhaust gas, passes through the exhaust manifold 16, is purified by the exhaust gas purification device 20, and reaches the silencer 17.

  The exhaust gas purification device 20 has a DPF 21 inside. The DPF 21 is a filter for collecting particulate matter contained in the exhaust gas. For example, the DPF 21 is made of ceramic and has a cross section having a honeycomb structure. That is, for example, a number of hexagonal-column straw-shaped polygonal through holes are adjacent to each other along the longitudinal direction from one end to the other end of the DPF 21, and each through hole has a predetermined interval along the longitudinal direction of the DPF 21. A porous partition is provided.

  Exhaust gas that has entered from one end side (incoming side) of the DPF 21 flows toward the other end side (outward side) of the DPF 21 while passing through a porous partition formed in the through hole. Particulate matter contained in the exhaust gas is collected by the DPF 21 by adhering to the porous partition walls or adhering to the inner wall of the through hole, and the exhaust gas purified by the DPF 21 is discharged to the outside. Although not shown, the exhaust system of the diesel engine 3 is an oxidation catalyst (not shown) for oxidizing the fuel in the particulate matter and the nitrogen oxide in the combustion gas between the entrance side of the DPF 21 and the engine 3. Diesel oxidation catalyst).

In the tractor 1 of the present invention, cleaning that reduces the amount of particulate matter deposited on the DPF 21 (referred to as PM deposition amount) under the control of the control unit 30 constituted by a CPU or the like, that is, regeneration of the DPF (referred to as DPF regeneration). Do).
The control unit 30 controls the operation of the entire tractor in addition to controlling the DPF regeneration. For example, an engine ECU 31 that mainly controls the engine 3 and various devices mounted on the tractor 1 in cooperation with the engine ECU 31 are provided. The main ECU 32 is controlled.

  The engine ECU 31 controls an injector, a common rail, a supply pump, and the like based on an operation amount of an accelerator lever, an operation amount of an accelerator pedal, a crank position, a cam position, or a control signal from the main ECU 32. The diesel engine control in the engine ECU 31 is the same as the general diesel engine control. For example, the fuel injection amount and the injection timing are set in the control of the injector, and the fuel injection pressure is set in the control of the supply pump and the common rail. Is set. As a matter of course, in the tractor 1, when the operator operates the accelerator lever or the accelerator pedal, the amount of operation of the accelerator lever or the amount of operation of the accelerator pedal changes, and the engine speed can be increased or decreased. it can.

The main ECU 32 performs various controls related to the tractor 1 separately from the engine ECU 31, and also performs control such that the engine speed is set in preference to the engine rotation control by the engine ECU 31.
For example, an engine rotation upper limit value set by a volume provided around the driver's seat 8 is input to the main ECU 32, and the main ECU 32 instructs the engine rotation speed by an accelerator lever or an accelerator pedal. When the value exceeds the engine rotation upper limit value, a command is output to the main ECU 32 so that the engine rotation speed does not exceed the engine rotation upper limit value, and the engine rotation speed is controlled with priority over the main ECU 32. In addition, the main ECU 32 controls the lifting and lowering of the three-point link mechanism 5 based on an operation lever provided around the driver's seat 8 and performs a shift control of the transmission.

Now, the DPF regeneration control according to the present embodiment is mainly performed by the main ECU 32. Specifically, when the deposition amount (PM deposition amount) of the particulate matter deposited on the DPF becomes equal to or greater than a predetermined value (greater than a predetermined threshold), the main ECU 32 controls the DPF regeneration, that is, the regeneration mode. It becomes.
Here, the PM accumulation amount is estimated based on the differential pressure between the exhaust pressure on the inlet side of the DPF 21 and the exhaust pressure on the outlet side of the DPF 21.

  Specifically, the exhaust pressure near the entry side of the DPF 21 (exhaust gas purification device 20) is detected by the entry pressure sensor 35, and the exhaust pressure near the exit side of the DPF 21 (exhaust gas purification device 20) is detected by the exit pressure sensor 36. The main ECU 32 detects the difference (difference) between the exhaust pressure detected by the inlet pressure sensor 35 and the exhaust pressure detected by the outlet pressure sensor 36 between the inlet side and the outlet side of the exhaust gas purification device 20. Pressure). When the PM accumulation amount is large, the differential pressure that is the difference in exhaust pressure is large, and when the PM accumulation amount is small, the differential pressure of the exhaust pressure is also small. Therefore, the main ECU 32 uses this relationship to calculate from the calculated differential pressure. The amount of PM deposited on the DPF is obtained. Note that the relationship between the differential pressure and the PM accumulation amount is stored in the main ECU 32 in the form of a control program or a control parameter in advance. In this embodiment, the PM accumulation amount is calculated from the difference in the exhaust pressure. However, the present invention is not limited to this, and the PM accumulation amount may be calculated based on the operating time when the engine 3 is operated, the fuel consumption amount, and the like. Any method for calculating the PM deposition amount may be used.

  The main ECU 32 includes a first temperature raising means 40, a first combustion condition determining means 41, a temperature rise confirmation means 42, and a second temperature raising means 43. The first temperature raising means 40, the first combustion condition determining means 41, the temperature raising confirmation means 42, and the second temperature raising means 43 are configured by a control program or the like stored in the main ECU 32, and the regeneration mode is a control program or the like. It operates by each means constituted by.

Hereinafter, the operation in the reproduction mode will be described together with each means.
The first temperature raising means 40 outputs a command to the engine ECU 31 or the like when the PM accumulation amount exceeds a predetermined value at which DPF regeneration must be performed, and the exhaust temperature in the exhaust gas purifying device 20 (the entrance side of the DPF 21) The exhaust gas temperature, that is, the temperature in the DPF 21) is raised as the first stage toward the first target temperature.

  Here, the first target temperature is, as will be described later, when the second stage temperature increase control is performed to further increase the exhaust gas temperature from the first target temperature, the temperature increase by the second stage temperature increase control is This is a temperature range in a stage where smooth progress is easily made, and the first target temperature is appropriately set depending on the performance of the temperature rise control in the second stage. For example, when the second stage temperature increase control is “post injection” in which the exhaust temperature is increased by fuel injection, the temperature is set to 250 ° C. to prevent oil dilution due to post injection. ing.

As shown in FIG. 2, specifically, when the PM accumulation amount becomes equal to or greater than a threshold value at which DPF regeneration must be performed, the first temperature raising means 40 sends a signal for commanding the throttle of the intake throttle to the engine ECU 31 or the like. And the intake throttle is throttled, whereby the exhaust temperature is automatically raised toward the first target temperature of 250 ° C.
The first temperature raising means 40 performs control to raise the exhaust temperature toward the first target temperature by narrowing the intake throttle, but the first temperature raising means 40 determines that the exhaust temperature is near the first target temperature. What is necessary is just to control to such extent. In other words, the temperature increase control by the first temperature increase means 40 is intended to increase the temperature in advance so that the temperature increase easily proceeds smoothly when the second temperature increase control is performed. The temperature rise by the first temperature raising means 40 may be a little over the first target temperature.

The first combustion condition determination unit 41 starts the temperature increase by the first temperature increase unit 40 (after the intake throttle is throttled), and the exhaust temperature on the inlet side of the DPF 21 becomes the first target temperature (for example, 250 ° C.). It is determined whether or not the temperature has reached the first target temperature.
Specifically, when the intake air throttle is throttled by the first temperature raising means 40, the first combustion condition determining means 41 measures the exhaust gas temperature by the temperature sensor 22 provided on the entry side of the DPF 21, and the temperature sensor 22. It is determined that the exhaust temperature after throttling of the intake throttle has reached the first target temperature when the exhaust temperature on the inlet side of the DPF 21 measured by the above becomes 250 ° C. or higher.

After it is determined that the exhaust temperature has reached the first target temperature, the temperature increase confirmation means 42 further determines whether or not to perform a temperature increase that raises the exhaust temperature to a temperature higher than the first target temperature. This should be confirmed with the operator who is driving the vehicle.
Specifically, after it is determined by the first combustion condition determination means 41 that the exhaust gas temperature has reached the first target temperature, the temperature increase confirmation means 42 is connected to the regeneration confirmation switch 44 installed around the driver's seat 8. Allow input. The temperature increase confirmation means 42 keeps the input permission state of the regeneration confirmation switch 44, and when the regeneration confirmation switch 44 is pressed (turned on), “the exhaust gas temperature is higher than the first target temperature. It is determined that the operator has confirmed that “the second stage temperature increase control to raise the temperature may be performed”. On the other hand, even if the exhaust temperature reaches the first target temperature, if the regeneration confirmation switch 44 is not pressed, it is not confirmed that the temperature rise confirmation means 42 may perform the second-stage temperature rise control. to decide.

  When it is confirmed that the second temperature raising means 43 raises the temperature (when the regeneration confirmation switch 44 is pressed), the exhaust temperature on the inlet side of the DPF 21 (temperature in the DPF 21). The second stage temperature rise control is performed to raise the temperature toward the second target temperature higher than the first target temperature. On the other hand, the second temperature raising means 43 does not perform the second stage temperature rise control when the second stage temperature rise control by the temperature rise confirmation means 42 is not confirmed.

  As shown in FIG. 2, for example, when the regeneration confirmation switch 44 is pressed at timing P, the second temperature raising means 43 immediately outputs a command to the engine ECU 31 and the like to start post injection and burn particulate matter. The exhaust gas temperature is raised at a stroke toward the second target temperature (600 ° C.), which is the temperature at which is promoted. When the temperature is raised by the second temperature raising means 43, the exhaust temperature is raised to around 600 ° C. all at once by post-injection, so that the DPF regeneration proceeds and the PM deposition amount decreases. As can be seen, the second target temperature is a temperature range in which the particulate matter deposited on the DPF 21 burns and the amount of PM deposition decreases, and is not limited to 600 ° C. as a matter of course.

FIG. 3 summarizes the operations in the playback mode in the first embodiment. In the description of FIG. 3, for convenience of explanation, it is assumed that, for example, a fertilizer spraying device, a harvesting device, and the like are attached as the working device 6 to the rear portion of the tractor 1 and the tractor 1 is working.
As shown in step S1 of FIG. 3, the main ECU 32 determines whether or not the PM accumulation amount is equal to or greater than the threshold value. If the PM accumulation amount is equal to or greater than the threshold value (step S1, yes), the process proceeds to step S2. In step S2, the main ECU 32 enters a regeneration mode. As shown in step S3, when in the regeneration mode, the first temperature raising means 40 throttles the intake throttle, and the exhaust temperature is raised to 250 ° C. (first target temperature).

  Next, as shown in step S4, when the temperature raising control of the exhaust temperature is performed by the first temperature raising means 40, it is determined whether or not the exhaust temperature has reached the first target temperature by the first combustion condition judging means 41. To be judged. As shown in step 3 and step S4, the throttle of the intake throttle by the first temperature raising means 40 is continued until the exhaust temperature reaches the first target temperature (exhaust temperature ≧ first target temperature).

Thereafter, when the first combustion condition determining means 41 determines that the exhaust temperature has reached the first target temperature (step S4, yes), the process proceeds to step S5. In step S5, it is confirmed whether or not to raise the exhaust temperature to a second target temperature higher than the first target temperature.
Thus, in the stage from step S1 to step S5, although the exhaust gas temperature rises due to DPF regeneration by the first temperature raising means 40, the exhaust temperature on the inlet side of the DPF 21 is about 250 ° C. There is little influence on crops and the like, and at this point, even if the regeneration mode is set, the operation of the tractor 1 may be continued as it is.

  However, if the particulate matter is combusted and raised to a second target temperature at which it can be reliably reduced, the temperature of the exhaust gas discharged from the tractor 1 is high, which may damage the crop. Therefore, between step S3 and step S4, the exhaust temperature is raised to the first target temperature that does not damage the crop and the second-stage temperature rise control proceeds smoothly. The exhaust temperature is further confirmed to be raised to the second target temperature. That is, in the present invention, when the amount of accumulated PM becomes equal to or higher than the threshold required for DPF regeneration, the temperature is automatically raised to the first target temperature, and further temperature rise is waited until instructed, After the operator's confirmation (instruction), that is, the processing in step S5, the exhaust temperature is raised in the second stage.

  For example, during work on the tractor 1, when the tractor 1 is traveling in a place where there is no combustible material such as crops even when the tractor 1 is in the field, or the work in the field is temporarily interrupted. When traveling on a farm road, etc., even if the exhaust temperature is raised above the first target temperature, the exhaust gas does not damage the crop and does not affect the work. As described above, when the work is not affected, the regeneration confirmation switch 44 can be pressed to immediately perform the DPF regeneration.

In step S5, when the regeneration confirmation switch 44 is pressed and the operator is confirmed (S5, yes), the process proceeds to step S6. In step S6, the second temperature raising means 43 switches from the throttle of the intake throttle to the post injection, the post injection is immediately performed, and the exhaust temperature is raised to about 600 ° C. of the second target temperature.
In this way, since the second stage post-injection is performed from the state where the exhaust gas temperature has been raised to the first target temperature in advance, when the regeneration confirmation switch 44 is pressed, the exhaust temperature immediately decreases by burning particulate matter. The level of particulate matter can be reduced. In particular, when post-injection is started under the condition where the temperature is equal to or higher than the first target temperature, the temperature rise when fuel is injected is good, so the time required for raising the exhaust temperature from the first target temperature to the second target temperature is short. In addition, it is possible to minimize the temperature rise failure (a phenomenon that the temperature does not easily rise) due to post injection.

As shown in step S7, it is determined whether or not the PM accumulation amount is less than the threshold value. If the PM accumulation amount is less than the threshold value (S7, yes), the post injection is stopped and the DPF regeneration is terminated.
As described above, according to the present invention, the work implement 1 includes the first temperature raising means 40, the first combustion condition determining means 41, the temperature raising confirmation means 42, and the second temperature raising means 43. For this reason, as described above, the PM accumulation amount can be reduced during the work without affecting the work, so that the DPF regeneration can be performed without affecting the work. In addition, the operator must confirm the temperature range in which the PM accumulation amount is reduced, and the exhaust gas temperature suddenly rises unintended by the operator (from the first stage temperature range to the second stage temperature range). Temperature rise), and the operator can continue working without worrying about the temperature rise due to DPF regeneration.

[Second Embodiment]
In the second embodiment, the operator is notified that the exhaust temperature has reached the first target temperature.
As shown in FIG. 4, specifically, the main ECU 32 includes a condition coincidence notification unit 45 that notifies the operator that the exhaust temperature has reached the first target temperature. The condition coincidence notification unit 45 is configured by a control program stored in the main ECU 32 and the like. The description of the same configuration as that of the first embodiment is omitted.

  When the first combustion condition determining unit 41 determines that the exhaust gas temperature has reached the first target temperature, the condition coincidence notification unit 45 displays the exhaust gas temperature on the display device 46 provided around the driver's seat 8. A notification signal indicating that the temperature has been reached is output. In response to the notification signal, the display device 46 notifies the operator that the exhaust temperature has reached the first target temperature, for example, by turning on or blinking the first notification unit 47 configured by an LED or the like.

  In this way, the operator looks at the first notification unit 47 of the display device 46 to confirm that the exhaust gas temperature has reached the first target temperature and is ready for the second stage temperature increase. I can grasp it. The temperature rise can be confirmed while considering the work status while looking at the first notification unit 47. In addition, the 1st alerting | reporting part 47 is not limited to what shows that exhaust temperature reached the 1st target temperature by lighting or blinking of LED as mentioned above, but exhaust gas temperature is 1st by the output of a sound and the display by a character. It may indicate that the target temperature has been reached.

[Third embodiment]
In 3rd Embodiment, the process after the temperature rising start by the 2nd temperature rising means 43 is further added with respect to 1st Embodiment or 2nd Embodiment.
As shown in FIG. 5, specifically, the main ECU 32 includes a second combustion condition determination unit 48 and a temperature increase continuation stop unit 49.

The second combustion condition determining means 48 and the temperature rise continuation stopping means 49 are configured by a control program or the like stored in the main ECU 32. Note that the description of the same configuration as the first embodiment and the second embodiment is omitted.
The second combustion condition determination means 48 determines whether or not the exhaust gas temperature is lower than the first target temperature after the second temperature increase means 43 starts the temperature increase. Specifically, while post injection is being performed, it is determined whether or not the exhaust temperature on the inlet side of the DPF 21 is lower than a first target temperature (for example, 250 ° C.).

When the second combustion condition determination unit 48 determines that the exhaust temperature is not lower than the first target temperature (above the first target temperature), the temperature increase continuation stopping unit 49 continues the temperature increase by the second temperature increase unit 43. The temperature increase continuation stopping means 49 stops the temperature increase by the second temperature increase means 43 when the second combustion condition determination means 48 determines that the exhaust temperature is lower than the first target temperature.
FIG. 6 summarizes the operations in the playback mode in the third embodiment. Steps 1 to 7 are the same as the operations described above.

  As shown in FIG. 6, when post-injection is started in step S6, in step S10, whether or not the exhaust gas temperature is lower than the first target temperature (less than 250 ° C.) is determined by the second combustion condition determination means 48. To be judged. If the exhaust gas temperature is not less than 250 ° C. (S10, no), the process proceeds to step S7. If the PM accumulation amount is not less than the threshold value in step 7, the process returns to step S6, The post injection command to the ECU 31 is continued. On the other hand, when the exhaust gas temperature is less than 250 ° C. (S10, yes), the routine proceeds to step S11, where the post-injection command to the engine ECU 31 is stopped by the temperature rise continuation stopping means 49, and the post-injection is stopped. When post injection is stopped, the process returns to step S3 and the process is continued.

  As described above, if post injection is performed with the exhaust temperature being 250 ° C. or higher, the exhaust temperature immediately rises to 600 ° C., but the load on the tractor 1 changes and rarely post injection is performed. However, the exhaust temperature does not rise in a short period of time and may be less than 250 ° C. In such a case, if post-injection is continued for a long time, fuel consumption deteriorates and oil dilution occurs. Therefore, in the third embodiment, for some reason, it is assumed that the exhaust temperature increases due to post-injection. If there is no increase in exhaust temperature due to post-injection, stop post-injection immediately and retry the post-injection when the exhaust temperature reaches 250 ° C or higher. It is intended to prevent deterioration and oil dilution.

FIG. 7 shows a first modification of the third embodiment.
As shown in FIG. 7, the main ECU 32 includes an out-of-condition notification unit 50 and a temperature increase guide unit 51 in addition to the second combustion condition determination unit 48 and the temperature increase continuation stop unit 49. A control program or the like stored in the main ECU 32 is used.
When the second combustion condition determining unit 48 determines that the exhaust gas temperature is lower than the first target temperature after the start of temperature increase by the second temperature increasing unit 43, the off-condition notifying unit 50 displays the exhaust temperature on the display device 46. A notification signal indicating that the temperature is lower than one target temperature is output. The display device 46 receives the notification signal and notifies the operator that the exhaust temperature is lower than the first target temperature by, for example, lighting or blinking the second notification unit 52 configured by an LED or the like.

  In this way, the operator grasps that the second stage temperature rise does not proceed smoothly by looking at the second notification unit 52 of the display device 46 after pressing the regeneration confirmation switch 44. It is possible to indirectly know that the temperature of the exhaust gas after the regeneration confirmation switch 44 is pressed is relatively low. The out-of-condition notification unit 50 may output a notification signal when the exhaust temperature is lower than the first target temperature for several seconds continuously.

  When the second combustion condition determination unit 48 determines that the exhaust gas temperature is lower than the first target temperature after the temperature increase starts by the second temperature increase unit 43, the temperature increase guide unit 51 causes the display device 46 to be manually operated. A guidance signal for guiding the increase in engine speed is output. In response to the guidance signal, the display device 46 lights up or blinks the guidance portion 53 composed of, for example, an LED or the like, thereby notifying the operator that the engine speed needs to be increased.

In this way, the operator can raise the exhaust temperature by operating the accelerator lever and increasing the engine speed by viewing the guide portion 53 of the display device 46 after pressing the regeneration confirmation switch 44. . The temperature raising guide means 51 may output a guidance signal when the exhaust temperature is lower than the first target temperature continuously for several seconds.
FIG. 8 summarizes the operations in the playback mode in the first modification of the third embodiment. In addition, step S1-step S7, step S10 are the same as the operation | movement mentioned above.

  As shown in FIG. 8, when post-injection is started in step S6, it is determined in step S10 whether or not the exhaust gas temperature is less than the first target temperature (less than 250 ° C.) by the second combustion condition determining means 48. Is done. If the exhaust temperature is less than 250 ° C. (S10, yes), the process proceeds to step 20, where the exhaust temperature is less than the first temperature by the off-condition notification means 50 and the second notification unit 52 of the display device 46. Notify that there is.

  Further, the process proceeds to step S21 and step S22, and the post-injection is stopped in step S21. In step S22, the engine speed is increased by manual operation by the temperature raising guide means 51 and the guide unit 53 of the display device 46. invite. If post injection is stopped and an increase in engine speed is guided, the process returns to step S3 and the processing is continued.

  According to the first modification, even when the exhaust temperature rise due to post injection does not go smoothly, the engine speed is increased by the operator operating the accelerator lever between operations, and the engine is manually operated. The increase in the exhaust temperature can be supplemented by the increase in the rotational speed. By performing this manual operation, the exhaust temperature once lowered can be quickly raised to a state where the post injection can be performed (the exhaust temperature is 250 ° C. or higher). In particular, since the exhaust temperature is raised by both the increase in the engine speed and the throttle of the intake throttle, the recovery process can be performed more quickly.

  In the first modification described above, when the exhaust temperature is not higher than the first target temperature but lower than the first target temperature after the start of temperature increase by the second temperature increase means 43 (after the start of post injection), the temperature is increased. Although the guide means 51 notifies that the engine speed is to be increased, the first temperature raising means 40 may be used even after the second temperature raising means 43 is not started to warm, as in a second modification described later. When the exhaust temperature does not become the first target temperature or higher after the start of the temperature increase, the temperature increase guide means 51 may notify that the engine speed is to be increased.

FIG. 9 summarizes the operations in the reproduction mode in the second modification. Note that steps S1 to S3, steps S5 to S7, and steps S20 to S22 are the same as those described above.
As shown in FIG. 9, as shown in step S <b> 4, the exhaust gas temperature reaches the first target temperature by the first combustion condition determining means 41 after the exhaust gas temperature raising control is performed by the first temperature raising means 40. It is determined whether or not (exhaust temperature ≧ first target temperature). Here, if the exhaust gas temperature does not reach the first target temperature and is lower than the first target temperature, the process proceeds to step S30. In step S30, the temperature raising guide means 51 outputs a guidance signal for guiding the display device 46 to increase the engine speed by manual operation. That is, in step S30, it is guided to increase the engine speed, and the process returns to step S3.

According to this, even if the exhaust temperature does not exceed the first target temperature due to the throttle of the intake throttle, the operator looks at the guide portion 53 of the display device 46 and increases the engine speed by manual operation. Therefore, the recovery process can be performed quickly.
That is, in the second modification, there is a case where the exhaust temperature is raised to the predetermined first target temperature or the second target temperature by the throttle of the intake throttle or post injection, but if the target temperature is not reached. Sometimes the engine speed can be increased manually.

[Fourth embodiment]
In the above-described embodiment, when the PM accumulation amount becomes equal to or greater than the threshold value, the exhaust temperature is automatically raised to the first target temperature, and after confirming the temperature rise, the exhaust temperature is made higher than the first target temperature. However, in the fourth embodiment, the DPF regeneration can be interrupted at any time between the operations. However, in the fourth embodiment, the DPF regeneration can be interrupted at any time between the operations. It is a thing.

  As shown in FIG. 10, specifically, the main ECU 32 includes a temperature rise interruption means 54. The temperature raising interruption means 54 is configured by a control program or the like stored in the main ECU 32. The description of the same configuration as that of the above-described embodiment is omitted. The temperature increase interrupting means 54 immediately interrupts (stops) the temperature increase by the second temperature increasing means 43 when an instruction to interrupt DPF regeneration is given from the outside.

  Specifically, after confirming the temperature rise, for example, the regeneration interruption switch 55 installed in the display device 46 is pressed (ON) in a situation where the post-injection is executed by the second temperature raising means 43 and the DPF regeneration is proceeding. When the DPF regeneration is instructed to the main ECU 32 by operating the regeneration interruption switch 55, the temperature raising interruption means 54 stops the temperature raising by the second temperature raising means 43.

In this way, even after confirming the temperature rise, the operator can interrupt DPF regeneration at any time by simply pressing the regeneration interruption switch 55 installed in the display device 46.
The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

In the above embodiment, the first temperature raising means 40 and the second temperature raising means are described as raising the exhaust gas temperature in order to burn the particulate matter in the DPF 21, but this is substantially In particular, the temperature in the DPF 21 is raised in order to burn the particulate matter, and there is no problem even if these exhaust temperatures are read as the temperature in the DPF 21 or the water temperature.
1st temperature rise means 40, 1st combustion condition judgment means 41, temperature rise confirmation means 42, 2nd temperature rise means 43, condition coincidence notification means 45, 2nd combustion condition judgment means 48, temperature rise continuation stop means 49, conditions The control program for configuring the detachment notification means 50, the temperature rise guidance means 51, etc. may be stored in the engine ECU 31 or the main ECU 32, or an electronic device mounted on the work implement (tractor 1). It may be stored in equipment. Further, the engine ECU 31 and the main ECU 32 may be integrated. The control in the engine ECU 31 and the main ECU 32 is not limited to the above-described ones, and various controls may be performed depending on the work machine to be applied. For example, if the work machine is a combiner, control suitable for the combine is performed. Control suitable for backhoes.

  The second notification unit 52 is not limited to indicating that the exhaust temperature is lower than the first target temperature by turning on or blinking the LED, and the exhaust temperature is lower than the first target temperature by outputting sound or displaying by text. It may indicate that. Moreover, the guide part 53 is not limited to what accelerate | stimulates an increase in engine speed by lighting or blinking of LED, You may accelerate | stimulate the increase in engine speed by the output of a sound and the display by a character. Furthermore, it is preferable that the guide unit 53 represents the target engine speed when the engine speed is increased, together with guidance for increasing the engine speed.

  In the above-described embodiment, the two-stage method in which the exhaust temperature is raised to the first target temperature and then raised to the second target temperature has been described. However, until the exhaust temperature reaches the first target temperature, the second target temperature is reached. The temperature may be divided into a plurality of stages such as two or more stages, for example, three stages or four stages. As a matter of course, the contents described in the above embodiments may be combined as appropriate. For example, the content of the fourth embodiment and the second embodiment may be combined, or may be combined with the first modification.

DESCRIPTION OF SYMBOLS 1 Tractor 2 Traveling vehicle body 3 Diesel engine 4 Transmission device 5 Three-point link mechanism 6 Working device 7 Cabin 8 Driver's seat 10 Cylinder 11 Intake port 12 Exhaust port 13 Intake valve 14 Exhaust valve 15 Intake manifold 16 Exhaust manifold 17 Silencer 20 Exhaust gas purification Equipment 21 DPF
22 Temperature sensor
30 Control unit 31 Engine ECU
32 Main ECU
35 Inlet pressure sensor 36 Outlet pressure sensor 40 First temperature raising means 41 First combustion condition determining means 42 Temperature rising confirmation means 43 Second temperature raising means 44 Regeneration confirmation switch 45 Condition coincidence notifying means 46 Display device 47 First notice Unit 48 Second combustion condition determining means 49 Temperature rise continuation stopping means 50 Condition off notification means 51 Temperature rise guide means 52 Second notification section 53 Guide section 54 Temperature rise interruption means 55 Regeneration interruption switch

Claims (4)

An exhaust gas purification device having a filter for collecting particulate matter contained in exhaust gas discharged from a diesel engine;
First temperature raising means for raising the exhaust temperature in the exhaust gas purification device toward the first target temperature when the amount of particulate matter deposited on the filter of the exhaust gas purification device is a predetermined value or more;
First combustion condition determining means for determining whether or not the exhaust temperature has reached a first target temperature after the temperature raising start by the first temperature raising means;
After the first combustion condition determining means determines that the exhaust temperature has reached the first target temperature, it is further determined whether or not to raise the exhaust temperature to a temperature higher than the first target temperature. A temperature rise confirmation means to confirm;
When the temperature rise confirmation means confirms that the temperature is to be raised, the exhaust temperature is raised to a second target temperature that is higher than the first target temperature and promotes the combustion of particulate matter. A temperature raising means;
A working machine characterized by comprising: Second combustion condition determining means for determining whether or not the exhaust gas temperature is lower than a first target temperature after the temperature raising start by the second temperature raising means;
If the exhaust temperature is not less than the first target temperature, the temperature rise by the second temperature raising means is continued. If the exhaust temperature is less than the first target temperature, the temperature rise continuation stopping means for stopping the temperature rise by the second temperature raising means. When,
The working machine according to claim 1, further comprising: An out-of-condition notifying means for notifying that the exhaust temperature is lower than the first target temperature after the temperature raising start by the second temperature raising means;
A temperature raising guide means for urging to raise the exhaust temperature by increasing the engine speed of the diesel engine when the temperature is lower than the first target temperature after the temperature raising start by the second temperature raising means;
The working machine according to claim 2, further comprising:   The work implement according to any one of claims 1 to 3, wherein the temperature rise confirmation means determines that the confirmation is made when a regeneration confirmation switch installed around the driver's seat is operated.

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