JP2022102933A - Work vehicle - Google Patents

Abstract

To protect an ECU for controlling an engine from heat.SOLUTION: In an engine comprising an ECU (100) that controls an engine (E), a thermo switch (73) is provided near the ECU (100); when the thermo switch (73) detects a temperature above a predetermined value, the thermo switch (73) is turned on; and when the thermo switch (73) is turned on after the engine is started, a fuel injection amount is changed to a smaller amount than a required fuel injection amount.SELECTED DRAWING: Figure 7

Description

The present invention relates to a work vehicle, and more particularly to deterioration and failure prevention of an ECU that controls an engine.

A technique is disclosed in which an air cleaner is fixed on a cylinder head of an engine via an air cleaner bracket, and an ECU is arranged in a space surrounded by the cylinder head, the air cleaner, and the air cleaner bracket (see, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2009-209699

The above-mentioned techniques have a problem that the ECU cannot be protected from heat.

An object of the present invention is to provide an engine that solves the above-mentioned problems.

The above object of the present invention is achieved by the following configuration.

That is, in the invention according to claim 1, in an engine provided with an ECU (100) for controlling an engine (E), a thermo switch (73) is provided near the ECU (100), and the thermo switch (73) is predetermined. When the temperature above the value is detected, the thermo switch (73) is turned on, and when the thermo switch (73) is turned on after the engine is started, the fuel injection amount is changed to less than the required fuel injection amount. It is a work vehicle characterized by this.

In the invention according to claim 2, the ECU (100) is attached to the bracket (70), the bracket (70) is attached to the engine via the mount rubber (71), and the portion covered with the bracket (70) is covered. It is a work vehicle characterized by being provided with an electric fan (72).

The work vehicle according to claim 1 or 2, wherein the invention according to claim 3 is provided with a notification means for notifying that the fuel injection amount has been changed to a smaller amount than the required fuel injection amount. It is a thing.

Since the present invention is configured as described above, the ECU can be protected from heat, and deterioration and failure of the ECU can be prevented.

Overall configuration of accumulator fuel injection system Diagram showing the relationship between engine speed and output torque in the control mode Left side view of the tractor Floor plan of the tractor Schematic diagram of intake system and exhaust system ECU mounting diagram ECU overheat prevention flowchart Plan view of the engine Side view of the engine Installation drawing of the aftertreatment device

The best mode for carrying out the present invention will be described.

FIG. 1 is an overall configuration diagram of a pressure-accumulation fuel injection device. The accumulator fuel injection device is applied to, for example, a multi-cylinder diesel engine, but may be a gasoline engine. Then, the accumulator fuel injection device pressurizes the common rail 1 that accumulates high-pressure fuel corresponding to the injection pressure, the pressure sensor 2 attached to the common rail 1, and the fuel pumped from the fuel tank 3 and pumps the fuel to the common rail 1. A high-pressure pump 4, a fuel injection nozzle 6 that injects high-pressure fuel accumulated in the common rail 1 into the cylinder 5 of the engine E, a control device (ECU) that controls the operation of the high-pressure pump 4, the fuel injection nozzle 6, and the like. Consists of. ECU is an abbreviation for engine control unit.

As described above, the common rail 1 injects fuel into each cylinder 5 of the engine E, and makes the fuel supply a required pressure.

The fuel in the fuel tank 3 is sucked into the high pressure pump 4 driven by the engine E through the fuel filter 7 through the suction passage, and the high pressure fuel pressurized by the high pressure pump 4 is guided to the common rail 1 by the discharge passage 8. It is stored and stored.

The high-pressure fuel in the common rail 1 is supplied to the fuel injection nozzles 6 for the number of cylinders by each high-pressure fuel supply passage 9, and the fuel injection nozzle 6 operates in each cylinder based on the command from the ECU 100, and the high-pressure fuel is supplied to the engine E. The surplus fuel (return fuel) in each fuel injection nozzle 6 is injected and supplied into each Sylunder 5 chamber, is guided to a common return passage 10 by each return passage 10, and is returned to the fuel tank 3 by this return passage 10.

Further, a pressure control valve 11 is provided in the high pressure pump 4 in order to control the fuel pressure (common rail pressure) in the common rail 1, and the pressure control valve 11 is provided from the high pressure pump 4 to the fuel tank 3 by a duty signal from the ECU 100. The flow path area of the return passage 10 of the surplus fuel to is adjusted, whereby the fuel discharge amount to the common rail 1 side can be adjusted to control the common rail pressure.

Specifically, the target common rail pressure is set according to the engine operating conditions, and the common rail pressure is feedback-controlled via the pressure control valve 11 so that the common rail pressure detected by the rail pressure sensor 2 matches the target common rail pressure. It has a structure.

As shown in FIG. 2, the ECU 100 of the diesel engine E having the common rail 1 in the work vehicle (agricultural work machine) has three types of traveling mode A, normal working mode B, and heavy working mode C in relation to the rotation speed and the output torque. It has a control mode.

The driving mode A is a droop control in which the output also fluctuates according to the fluctuation of the engine speed. It is used when traveling on the move without performing farm work. For example, when the brake is applied to reduce or stop the traveling speed, the engine speed decreases as the traveling load increases, so that the traveling speed can be reduced or stopped safely.

The normal work mode B is isochronous control in which the engine speed is constant and the output is changed according to the load even if the load fluctuates. It is used when performing normal farm work. For example, in the case of a tractor, the cultivated land is hard during cultivating work and resistance is applied to the cultivating blade, and in the case of a combine harvester, the output fluctuates and the rotation speed is maintained even when the load increases due to a large amount of harvested material. It's time.

In the heavy work mode C, as in the normal work mode B, in addition to the isochronous control that changes the output according to the load at a constant engine speed even if the load fluctuates, the speed is increased and the output is increased when the load limit is approached. It is a control with a heavy load control that raises. In particular, it is used when farming near the load limit. For example, when cultivating with a tractor, especially when encountering hard cultivated land, the engine output increases beyond the normal limit, so the work is not interrupted and efficient work is possible. ..

These work modes A, B, and C are the operation of the work mode changeover switch that can switch each work mode A, B, C, or the shift operation of the traveling speed change lever of the agricultural work vehicle (tractor, combine, rice transplanter, etc.). Alternatively, the work clutch (rotary in the case of a tractor, cutting section and threshing section in the case of a combine) is configured to be switched by an on / off operation or the like.

In the diesel engine E, it is possible to shorten the ignition delay, reduce the knocking noise peculiar to the diesel engine E, and reduce the noise by performing the pilot injection that injects a small amount of fuel in a pulsed manner prior to the main injection. The configuration is as follows.

This pilot injection was performed only once or twice before the main injection, but by using the accumulator fuel injection device of the common rail 1, the pilot injection is performed according to the situation of the engine E. It becomes possible to reduce noise and suppress the generation of white smoke or black smoke due to incomplete combustion. Further, by performing the pilot injection in which a small amount of fuel is pulsedly injected prior to the main injection, the amount of nitrogen oxides in the exhaust gas is reduced.

FIG. 3 shows a side view of a tractor equipped with a diesel engine having a common rail 1 as described above, and FIG. 4 shows a plan view thereof. The plan view shows a state in which the cabin 14 shown in FIG. 3 is omitted.

The tractor is provided with front wheels 12, 12 and rear wheels 13, 13 at the front and rear parts of the airframe, and the rotational power of the engine E mounted on the front part of the airframe is appropriately decelerated by a transmission in the transmission case T, and these front wheels 12 are used. , 12 and the rear wheels 13, 13.

A steering handle 16 is supported by a handle post 15 in the cabin 14 at the center of the fuselage, and a seat 17 is provided behind the steering handle 16. Below the steering handle 16, a forward / backward lever 18 for switching the traveling direction of the aircraft in the front-rear direction is provided. When the forward / backward lever 18 is moved to the front side, the aircraft moves forward, and when it is moved backward, the aircraft moves backward.

An accelerator lever 25 for adjusting the engine speed is provided on the opposite side of the forward / backward lever 18 with the handle post 15 interposed therebetween, and an accelerator for adjusting the engine speed is similarly provided at the right corner of the step floor 19. The pedal 23 and the left and right rear wheels 13 and 13 are provided with left and right brake pedals 24L and 24R for operating the brakes. A clutch pedal 20 is provided at the left corner of the step floor 19.

Further, the main shift lever 26 is located on the left front portion of the seat 17, and the auxiliary shift lever 27 capable of selecting any of low speed, medium speed, high speed and neutral positions is located behind the main shift lever 26, and the PTO shift lever 28 is further to the right of the auxiliary shift lever 27. Is provided. Further, on the right side of the seat 17, a position lever 29 for setting the height of the working machine 21 (rotary or the like), an automatic tilling depth lever 30 for automatically setting the tilling depth of the field, and a working machine 21 after these levers. The right-up switch 31 and the right-down switch 32 are arranged, and then the automatic horizontal switch 33 and the backup switch 34 of the working machine 21 are arranged. The backup switch 34 automatically raises the working machine 21 when the machine is moving backward. The working machine 21 is configured to be connected to the rear of the machine body by a link 22. The tractor drives the work machine 21 to run the machine to perform work such as tilling in the field. Reference numeral 21a is a hydraulic cylinder that raises and lowers the working machine 21.

FIG. 5 is a schematic diagram of intake and exhaust into the cylinder 5 of the engine, and is an example of a four-cycle diesel engine. The air supercharged by the intake turbine 36 of the supercharger TB passes through the intake turbine 36 and the intercooler 37 from the air cleaner 35, and is sent from the intake manifold 38 into the cylinder 5. 39 is an intake valve and 40 is a piston. Reference numeral 48 is a cam that opens and closes the intake / exhaust valves 39 and 41 via the rocker arm 49.

The exhaust gas burned in the cylinder 5 is configured to be discharged by driving the supercharger TB by the exhaust turbine 45 of the supercharger TB after passing through the exhaust manifold 42 from the exhaust valve 41.

This diesel engine has an EGR (exhaust gas recirculation device) circuit 44 for mixing a part of exhaust gas into the intake side. The EGR circuit is configured to reduce the amount of oxygen (O2) by mixing a part of the exhaust gas into the intake side to reduce the generation of nitrogen oxide Nox. However, if the EGR rate rises too much, the amount of oxygen decreases and incomplete combustion occurs. Therefore, it is necessary to adjust the EGR rate according to the combustion state. This adjustment is performed by the EGR valve 43. The EGR circuit 44 connects the exhaust pipe 55 on the downstream side of the aftertreatment device 46, which will be described later, to the intake pipe 56 on the upstream side of the intake turbine 36 of the turbocharger TB. Further, an EGR cooler 57 is provided in the middle of the EGR circuit 44. The amount of exhaust gas returned to the cylinder 5 changes depending on how the EGR valve 43 is opened and closed.

The exhaust gas after passing through the exhaust turbine 45 passes through the aftertreatment device 46 and is discharged to the atmosphere from the muffler 50. The aftertreatment device 46 is composed of an oxidation catalyst (DOC) 46a and a diesel particulate filter (DPF) 46b.

The oxidation catalyst (DOC) burns the incombustible chamber, and the diesel particulate filter (DPF) is for collecting the granulated substance (PM). The EGR valve 43 and the throttle valve 47 are configured to be controlled by the ECU 100. The aftertreatment device 46 may be composed of only the diesel particulate filter (DPF) 46b. If the oxidation catalyst (DOC) is provided, the incombustible substance is burned, so that the exhaust gas becomes cleaner.

If the temperature of the exhaust gas of the DPF46b is low (low load) for a long time, PM is accumulated and there is a concern that the capacity of the DPF46b is lowered. Therefore, if a throttle valve 47 is provided on the lower side of the post-treatment device 46 and the throttle valve 47 is throttled, the pressure in the DPF 46b is kept high, so that the temperature also rises. As a result, the DPF46b can be regenerated due to the influence of the high temperature. That is, when the exhaust gas having a high temperature passes through the DPF46b, the PM existing in the DPF46b is burnt off and the DPF46b is regenerated.

As the DPF regeneration operation for regenerating the DPF 46b, both the EGR valve 43 and the throttle valve 47 are throttled. Then, the gas temperature in the DPF46b is raised in combination with the retard (retard) of the fuel injection timing so that the DPF46b enters the regeneration. As a result, after-injection of fuel (to raise the exhaust gas temperature) becomes unnecessary, and the number of after-injections can be reduced, so that fuel consumption can be suppressed, which is good for the environment.

As a condition for performing such a DPF regeneration operation, a pressure sensor 52 is provided on the upper side of the post-processing device 46, and a pressure sensor 53 is also provided on the lower side of the post-processing device 46, and the pressure difference is equal to or larger than a predetermined value. When it becomes, PM is accumulated in the DPF46b and becomes a resistance, so the DPF regeneration operation is performed. Further, instead of the pressure sensor 52, the pressure sensor 58 may be provided between the DOC 46a and the DPF 46b.

Further, if the state of entering the DPF regeneration operation continues for a long time, the DPF 46b will be damaged due to an overheated state. Therefore, a temperature sensor 59 is provided on the lower side of the aftertreatment device 46, and when the value of the temperature sensor 59 exceeds a predetermined value, the DPF regeneration operation is stopped and the normal operation is returned.

In normal operation, the EGR valve 43 and the throttle valve 47 are controlled at the same time so that the EGR amount is appropriately controlled. In particular, by having the throttle valve 47, the gas temperature in the DPF 46b can be kept high.

The above-mentioned configuration eliminates the need for an intake throttle. That is, since the pressure on the intake side is high in an engine with a supercharger, it is necessary to provide an exhaust throttle valve or an intake throttle to secure the amount of EGR gas and control in conjunction with the EGR valve, but such a system is unnecessary. Will be.

Further, since the exhaust gas downstream of the DPF46b is taken out, it becomes possible to prevent the performance deterioration due to the contamination of the turbocharger TB. Since the EGR gas is cooled by the EGR cooler 57, the effect on reducing NOx is greater.

As described above, in the DPF forced regeneration mode in which the DPF regeneration operation is performed, the exhaust throttle valve 47 is throttled and the EGR valve 43 is fully closed by ON-OFF control. Therefore, since the exhaust gas is not reduced, NO increases, and this NO is converted to NO2 by the oxidation catalyst (DOC) 46a, and the regeneration of DPF46b is promoted.

Further, when the engine rotation shifts to low idle during the forced regeneration of the DPF 46b, the EGR valve 43 is fully opened. Since the temperature sensor 59 is provided on the downstream side of the DPF 46b, it may be added to the condition that the value detected by the temperature sensor 59 rises above a predetermined value.

When the throttle valve 47 is throttled to perform forced regeneration of the DPF 46b, the engine speed is set to a low speed to increase the amount of oxygen supplied, and the exhaust gas flow velocity is reduced to facilitate the temperature rise. However, when the engine speed is changed to low idle or its vicinity during regeneration, soot burns rapidly due to an increase in the amount of oxygen supplied and a decrease in the flow velocity. As a result, the temperature may rise rapidly and the DPF46b may be damaged. Therefore, it is necessary to control the soot so that the maximum temperature does not exceed the allowable temperature.

Therefore, when the temperature sensor 59 exceeds a predetermined value, the engine speed is configured to increase to the medium speed range. As a result, the flow velocity of the exhaust gas is increased, so that the maximum temperature is lowered and damage to the DPF46b can be prevented. Further, if the value of the predetermined value of the temperature sensor 59 is controlled in the vicinity of the limit value, the DPF 46b can be efficiently regenerated.

In raising the engine speed to the medium speed range, the engine speed may be increased to the maximum speed and then decelerated to the medium speed range. As a result, the exhaust gas once flows at the maximum speed, so that preheating is performed. It becomes possible to prevent the DPF46b from being heated and exceeding the threshold temperature due to such factors.

Further, during the forced regeneration of the DPF46b, when the engine speed is shifted to low idle as described above, the post injection is interrupted, and then the engine speed is increased to the maximum speed to shift to the medium speed range. The post injection is restarted at. As a result, a sudden rise in the exhaust gas temperature can be suppressed, so that damage to the DPF 46b can be prevented.

When the differential pressure around DPF46b becomes more than a predetermined value, the driver automatically regenerates DPF46b by selecting the reproduction mode of DPF46b with the selection switch 67 after the work, and automatically stops the engine after reproduction of DPF46b. Configure to do. The differential pressure before and after DPF46b is monitored by the pressure sensors 58 and 53. When the differential pressure before and after the DPF46b immediately before the engine is stopped is equal to or higher than a predetermined value, a warning lamp or an alarm is used to notify the driver, and the driver operates a switch (not shown) for reproducing the DPF46b by himself / herself.

Then, even when the engine key is in the off position, by selecting the reproduction mode, the engine maintains the rotation in the idling state and executes the reproduction of the DPF46b. When the differential pressure around DPF46b becomes less than a predetermined value, the engine is automatically stopped.

As a result, the DPF46b can be automatically regenerated and the engine can be stopped even after the work is completed, so that the driver can perform other work away from the machine.

When the DPF46b is regenerated, as shown in FIG. 5, the air on the intake side may be configured to be sent from the pipeline 61 to the upstream side of the DPF46b. That is, when the DPF46b is regenerated, the valve 60 may be opened to send the air on the intake side on the upstream side of the turbocharger TB having a large amount of oxygen to the upstream side of the DPF46b. As a result, the reproduction efficiency is improved.

Further, the temperature of the DPF 46b may be monitored by the temperature sensors 62 and 59, and the temperature rise during regeneration may be confirmed in three steps. First, the intake air is throttled (not shown), and the temperature rise is confirmed in the throttled state of the intake air. Next, the first post injection is performed to confirm the temperature rise. At this point, if the temperature before and after the DPF46b does not reach 250 degrees, further temperature rise cannot be expected even if the second post injection is performed, so the reproduction is temporarily interrupted. Of course, if the temperature is 250 degrees or higher, the second post injection is performed to regenerate the DPF46b.

As shown in FIG. 5, an air-fuel ratio sensor 63 is provided on the downstream side of the DPF 46b. When the DPF46b is regenerated by performing post injection, if the fuel injection amount is too large, the fuel efficiency deteriorates, and if it is too small, the temperature does not rise and the regeneration cannot be performed. Therefore, the value of the air-fuel ratio sensor 63 is fed back to the ECU 100 to determine the injection amount. As a result, the fuel consumption is appropriate and the DPF46b can be regenerated. Further, instead of the air-fuel ratio sensor 63, the pressure value in the intake manifold may be fed back.

In the case of a plurality of cylinders, the combustion of some cylinders may be stopped when the DPF 46b is regenerated as described above. In this way, by stopping the combustion of some cylinders, even if the friction of the engine is the same, the load per cylinder may be increased to raise the exhaust temperature.

In the EGR valve 43, soot and HC adhere to the EGR valve 43 and are integrated with water such as dew condensation to form a viscous liquid. In such a state, the EGR valve 43 operates, but when the engine is stopped and the engine cools, the viscous liquid sticks, and when the engine is restarted, the EGR valve 43 may not move. In order to solve such a problem, the EGR valve 43 is provided with a cleaning function. That is, by forcibly operating the EGR valve 43 during the afterrun after the engine is stopped to remove the viscous liquid, the EGR valve 43 does not stick even if the engine cools.

During the work of the tractor, the smoke concentration and the excess of HC due to the load fluctuation contribute to the sticking of the EGR valve 43. In particular, at the start of turning, the load drops at once, resulting in an excess of HC, so the possibility of the EGR valve 43 increases.

Therefore, when the tractor is in a turning state (steering rotation angle of the steering handle 16 is equal to or greater than a predetermined value) during work running, the EGR valve 43 is temporarily closed, and when the tractor becomes stable with a low load after a predetermined time, it is determined. It is configured so that an appropriate opening (steady opening: a value corresponding to the NOX value) is obtained after performing the opening / closing operation (preliminary operation) a plurality of times. This is because when the tractor is switched to the turning state during work running, the load is suddenly released and smoke is generated, so that the EGR valve 43 is likely to be stuck.

The ECU 100 may be provided at an arbitrary position on the machine body such as in the engine room or the handle post, but in an agricultural machine such as a tractor, vibration is intense and the temperature becomes high depending on the season. Therefore, the ECU 100 It is necessary to be careful about the installation of.

Therefore, as shown in FIG. 6, the ECU 100 is placed on the bracket 70 and fixed with screws or the like, and the bracket 70 is attached to the engine or the airframe side via the mount rubber 71. As a result, it is possible to suppress the vibration of the airframe from being transmitted to the ECU 100, and it is possible to prevent damage to the ECU 100. Further, an electric fan 72 is provided in the bracket 70 to blow air to the ECU 100. Since the bracket 70 serves as a wind guidance guide and the wind efficiently hits the ECU 100, the cooling efficiency is improved and damage to the ECU 100 can be prevented. The electric fan 72 may be provided on the bracket 70 side, or may be provided on the engine side or the vehicle side on which the engine is mounted.

The electric fan 72 is not always driven, but is turned on when the thermo switch 73 provided near the ECU 100 reaches a temperature equal to or higher than a predetermined temperature, thereby driving the electric fan 72. As a result, extra power consumption can be suppressed.

Further, when the heat source exists near the electric fan 72, the electric fan 72 is configured to reverse the electric fan 72 so that the generated wind is directed toward the heat source. This makes it possible to prevent hot air near the heat source from being directed toward the ECU 100.

A thermo switch 73 is provided near the ECU 100, and when the thermo switch 73 detects a temperature equal to or higher than a predetermined value, the thermo switch 73 is turned on. Then, when the thermo switch 73 is turned on after the engine is started, the fuel injection amount is changed to a smaller amount than the required fuel injection amount.
This makes it possible to prevent deterioration and failure of the ECU 100.

Further, the ECU 100 is attached to the bracket 70, and the bracket 70 is attached to the engine via the mount rubber 71. Further, the electric fan 72 is provided in the portion covered by the bracket 70.

Thereby, the ECU 100 can be protected from the influence of vibration.

Further, since the notification means for notifying that the fuel injection amount has been changed to be smaller than the required fuel injection amount is provided, it is possible to prevent erroneous recognition as a failure.

When the thermo switch 73 is turned off, the fuel injection amount is returned to the normal level. Even if the thermo switch 73 is turned on after the engine is restarted, the electric fan 72 may be driven.

FIG. 8 shows a plan view of the engine. The DPF 46b and the intake throttle valve 74 are located at the top of the engine. The intake throttle valve 74 and the intake manifold 76 are connected by a pipe or hose made of aluminum, resin, or rubber. This makes it possible to arrange the intake throttle valve 74 with a simple configuration.

Further, another arrangement configuration of the intake throttle valve 74 will be described. As shown in the side view of the engine of FIG. 9, the DPF46b is arranged on the upper part of the engine. The intake throttle valve is located at the top of the engine and as close to the intake manifold 76 as possible. The intake throttle valve 74 is arranged at an angle of about 45 degrees around the valve axis. The intake throttle valve is located closer to the fan 75 than the DPF46b. The intake throttle valve 74 and the intake manifold 76 are connected by a pipe or hose made of aluminum, resin, or rubber. A part of the piping connecting the intake throttle valve 74 and the turbo 77 is made of aluminum / resin to reduce the cost. As a result, the intake throttle valve 74 can be arranged with a simple configuration.

Although not shown, the intake throttle valve 74 is a space between the fan 75 and the engine, and the intake throttle valve 74 is arranged so as to overlap the fan 75 as much as possible when viewed from the side, so that the compact can be arranged. Become.

FIG. 10 shows the mounting configuration of the aftertreatment device 46 for the engine. The hood bracket 78 is attached to the side surface of the engine with bolts 79. The upper side 78a of the DPF bracket is formed on the hood bracket 78 by welding or the like. The DPF46b is sandwiched between the DPF bracket upper side 78a and the DPF bracket lower side 79, and is fastened with a plurality of bolts 80. As a result, the space portion 82 is secured above the cylinder head 81 of the engine, so that maintenance related to the engine becomes easy.

When driving in the field with a tractor, input the position and shape of the field. When the work start button is pressed, data acquisition related to work information is started. For example, data such as a work start position, a work speed, a turning position, and a work end position in a field are stored in the CPU. At the time of the next work, the field is specified by inputting the position of the field to be worked on, and when the start button is pressed, the user is guided to the memorized previous work start position. This facilitates work running.

It can also be used for other vehicles such as agricultural work machines such as tractors and combines.

E Engine 70 Bracket 71 Mount Rubber 72 Electric Fan 73 Thermo Switch 100 ECU

Claims (3)

In an engine provided with an ECU (100) for controlling an engine (E), a thermo switch (73) is provided near the ECU (100), and when the thermo switch (73) detects a temperature equal to or higher than a predetermined value, the thermo switch (73) is provided. A work vehicle having a configuration in which 73) is turned on, and when the thermo switch (73) is turned on after the engine is started, the fuel injection amount is changed to a smaller amount than the required fuel injection amount. The ECU (100) is attached to the bracket (70), the bracket (70) is attached to the engine via the mount rubber (71), and the electric fan (72) is provided in the portion covered by the bracket (70). A work vehicle characterized by that. The work vehicle according to claim 1 or 2, wherein a notification means for notifying that the fuel injection amount has been changed to be smaller than the required fuel injection amount is provided.

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