Engine equipment

Abstract

To further properly remove deposit accumulated on a cylinder injection valve.SOLUTION: If a first counter increased when a fuel pressure of a high-pressure supply tube is less than a first predetermined value reaches a first threshold value or more, first removal processing is executed, in which deposit accumulated on a cylinder injection valve by injecting a fuel from the cylinder injection valve while the fuel pressure of the high-pressure supply tube is made to be the first predetermined pressure or more. If a second counter, increased when the fuel pressure of the high-pressure supply tube is less than a second predetermined pressure higher than the first predetermined pressure and a tip end temperature of the cylinder injection valve is a predetermined temperature or more, reaches a second threshold value or more, second removal processing is executed, in which the deposit accumulated on the cylinder injection valve is removed by injecting a fuel from the cylinder injection valve while the fuel pressure of the high-pressure supply tube is made to be the second predetermined pressure or more.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to an engine device, and more particularly to an engine device including an engine having a port injection valve and a direct injection valve. [Background technology]

[0002] Conventionally, as this type of engine device, there has been proposed a device that calculates a counter value for estimating the amount of deposits accumulated in the in-cylinder injection valve, and executes a deposit removal process for the in-cylinder injection valve when the counter value exceeds a threshold value (see, for example, Patent Document 1). In this device, when a request is made to increase the fuel injection amount beyond a basic fuel injection amount, the device calculates an amount of boost to the fuel pressure of the fuel supplied to the in-cylinder injection valve, and boosts the fuel pressure according to the amount of boost. By calculating the counter value according to the fuel pressure, the device performs a more appropriate deposit removal process for the in-cylinder injection valve. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2018-178849 A Summary of the Invention [Problem to be solved by the invention]

[0004] The inventors' analysis has revealed that, when the tip temperature of the in-cylinder injection valve is low, thermoplastic deposits tend to accumulate, and when the tip temperature is high, thermosetting deposits tend to accumulate. It has also been found that, while thermoplastic deposits can be removed by increasing the fuel pressure in the high-pressure supply pipe that supplies fuel to the in-cylinder injection valve to a certain level and injecting fuel from the in-cylinder injection valve, thermosetting deposits cannot be removed unless the fuel pressure is further increased and fuel is injected from the in-cylinder injection valve. For this reason, there are cases in which deposits cannot be removed using the deposit removal process using the counter value calculated according to the above-mentioned fuel pressure.

[0005] The main object of the engine apparatus of the present invention is to more appropriately remove deposits that build up on a direct injection valve. [Means for solving the problem]

[0006] In order to achieve the above-mentioned main object, the engine device of the present invention employs the following means.

[0007] The engine device of the present invention comprises: an engine having a port injection valve and a direct injection valve; a fuel supply device including a low-pressure pump that pressure-feeds fuel from a fuel tank to a low-pressure supply pipe to which the port injection valve is connected, and a high-pressure pump that pressure-feeds fuel from the low-pressure supply pipe to a high-pressure supply pipe to which the in-cylinder injection valve is connected; a control device for controlling the engine and the fuel supply device; An engine device comprising: The control device includes: when a first counter, which is incremented when the fuel pressure in the high-pressure supply pipe is less than a first predetermined pressure, reaches a first threshold value or more, a first removal process is performed in which the fuel pressure in the high-pressure supply pipe is set to a state equal to or greater than the first predetermined pressure, fuel is injected from the direct injection valve, and deposits accumulated in the direct injection valve are removed; when a second counter, which is incremented when the fuel pressure in the high-pressure supply pipe is less than a second predetermined pressure higher than the first predetermined pressure and the tip temperature of the in-cylinder injection valve is equal to or higher than a predetermined temperature, reaches a second threshold value or more, a second removal process is performed in which the fuel pressure in the high-pressure supply pipe is set to a state equal to or higher than the second predetermined pressure, fuel is injected from the in-cylinder injection valve, and deposits accumulated in the in-cylinder injection valve are removed. It is characterized by:

[0008] In the engine system of the present invention, when a first counter, which increases when the fuel pressure in a high-pressure supply pipe connected to the in-cylinder injection valve is below a first predetermined pressure, reaches or exceeds a first threshold, a first removal process is performed in which the fuel pressure in the high-pressure supply pipe is set to a state equal to or above the first predetermined pressure, fuel is injected from the in-cylinder injection valve, and deposits accumulated in the in-cylinder injection valve are removed. Since the first counter, which increases when the fuel pressure in the high-pressure supply pipe is below the first predetermined pressure, corresponds to the accumulation of thermoplastic deposits in the in-cylinder injection valve, by performing the first removal process when the first counter reaches or exceeds the first threshold, the thermoplastic deposits accumulated in the in-cylinder injection valve can be successfully removed. In addition, in the engine device of the present invention, when the second counter, which is increased when the fuel pressure in the high-pressure supply pipe is less than a second predetermined pressure higher than the first predetermined pressure and the tip temperature of the in-cylinder injection valve is equal to or higher than a predetermined temperature, reaches a second threshold value or higher, a second removal process is performed to remove deposits accumulated in the in-cylinder injection valve by injecting fuel from the in-cylinder injection valve with the fuel pressure in the high-pressure supply pipe at or above the second predetermined pressure. Since the second counter, which is increased when the fuel pressure in the high-pressure supply pipe is less than a second predetermined pressure higher than the first predetermined pressure and the tip temperature of the in-cylinder injection valve is equal to or higher than a predetermined temperature, corresponds to the accumulation of thermosetting deposits in the in-cylinder injection valve, the second removal process is performed when the second counter reaches the second threshold value or higher, so that the thermosetting deposits accumulated in the in-cylinder injection valve can be removed satisfactorily. As a result, the deposits accumulated in the in-cylinder injection valve can be removed more appropriately.

[0009] Here, as the first predetermined pressure, it is preferable to use the minimum fuel pressure that can remove thermoplastic deposits accumulated on the in-cylinder injection valve, and for example, 10 MPa, 12 MPa, 14 MPa, etc. can be used. As the first predetermined pressure, it is preferable to use the minimum fuel pressure that can remove thermosetting deposits accumulated on the in-cylinder injection valve, and for example, 18 MPa, 20 MPa, 22 MPa, etc. can be used. As the predetermined temperature, it is preferable to use the minimum temperature at which thermosetting deposits accumulate on the in-cylinder injection valve, and for example, 140°C, 150°C, 160°C, etc. can be used.

[0010] In the engine system of the present invention, the control device may increment the first counter and the second counter when the engine cooling water temperature is equal to or higher than a predetermined water temperature and the tip temperature of the in-cylinder injection valve is equal to or higher than the predetermined temperature. Since the tip temperature of the in-cylinder injection valve varies depending on the cylinder, the increment of the first counter and the second counter can be set on the safe side by setting the condition that the engine cooling water temperature is equal to or higher than the predetermined water temperature.

[0011] In the engine apparatus of the present invention, the first counter may be increased by a first increase amount when the fuel pressure in the high-pressure supply pipe is less than the first predetermined pressure and fuel injection is performed from the port injection valve when the cooling water temperature of the engine is equal to or higher than a predetermined water temperature, and decreased by a first decrease amount when the fuel pressure in the high-pressure supply pipe is equal to or higher than the first predetermined pressure and fuel injection is performed from the in-cylinder injection valve; and the second counter may be increased by a second increase amount when the fuel pressure in the high-pressure supply pipe is less than the second predetermined pressure and the tip temperature of the in-cylinder injection valve is equal to or higher than the predetermined temperature and fuel injection is performed from the port injection valve or the in-cylinder injection valve when the cooling water temperature of the engine is equal to or higher than the predetermined water temperature, and decreased by the second decrease amount when the fuel pressure in the high-pressure supply pipe is equal to or higher than the second predetermined pressure and fuel injection is performed from the in-cylinder injection valve. Since the thermoplastic deposits counted by the first counter are gradually removed by fuel injection from the in-cylinder injection valve when the fuel pressure in the high-pressure supply pipe is equal to or higher than a first predetermined pressure, the first counter can more accurately indicate the amount of thermoplastic deposits by taking into account the increment of the first counter. Also, the thermosetting deposits counted by the second counter are gradually removed by fuel injection from the in-cylinder injection valve when the fuel pressure in the high-pressure supply pipe is equal to or higher than a second predetermined pressure, so the second counter can more accurately indicate the amount of thermosetting deposits by taking into account the increment of the second counter. As a result, deposits that have accumulated on the in-cylinder injection valve can be more accurately removed.

[0012] In the engine system of the present invention in which the removal process is performed using the first and second counters that take such down into consideration, the first up amount and the second up amount may be a value of 1, the first down amount increases as the fuel pressure in the high-pressure supply pipe increases within a range equal to or greater than the first predetermined pressure, and the second down amount increases as the fuel pressure in the high-pressure supply pipe increases within a range equal to or greater than the second predetermined pressure. This is based on the fact that the higher the fuel pressure in the high-pressure supply pipe, the greater the effect of removing deposits. As a result, the first counter more accurately indicates the amount of thermoplastic deposits, and the second counter more accurately indicates the amount of thermosetting deposits.

[0013] In the engine device of the present invention in which the removal process is performed using a first counter and a second counter that take down into consideration, the first removal process may be terminated when the first counter reaches a value of 0, and the second removal process may be terminated when the second counter reaches a value of 0. This makes it possible to more reliably remove deposits. In this case, the first removal process and the second removal process may be executed when the power required of the engine is less than a predetermined power, and may be interrupted when the power required of the engine is equal to or greater than the predetermined power. Here, the predetermined power may be considered to be the degree to which a creep torque is output when the engine is mounted on a vehicle. [Brief description of the drawings]

[0014] [Figure 1] 1 is a configuration diagram showing an outline of the configuration of an engine device 10. FIG. [Diagram 2] 4 is an explanatory diagram showing an example of input / output signals of an electronic control unit 70. FIG. [Diagram 3] 6 is a flowchart showing an example of a deposit removal process executed by an electronic control unit 70. [Figure 4] 4 is a flowchart showing an example of a first counter process executed by the electronic control unit 70; [Diagram 5]10 is a flowchart showing an example of a second counter process executed by the electronic control unit 70. [Figure 6] 11 is a table showing a list of counting processing conditions of a first counter Cs. [Figure 7] FIG. 4 is an explanatory diagram showing an example of a first down amount setting map. [Figure 8] 11 is a table showing a list of counting process conditions of a second counter Cs. [Figure 9] FIG. 4 is an explanatory diagram showing an example of a second down amount setting map. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] Next, a mode for carrying out the present invention will be described using examples. EXAMPLES

[0016] Fig. 1 is a schematic diagram showing the configuration of an engine device 10 according to an embodiment of the present invention, and Fig. 2 is an explanatory diagram showing an example of input / output signals of an electronic control unit 70. The engine device 10 according to the embodiment is mounted on a general vehicle that runs using power from an engine 12, or on various hybrid vehicles that are equipped with a motor in addition to the engine 12, and includes the engine 12, a turbocharger 40, a fuel supply device 16, and an electronic control unit 70, as shown in Figs. 1 and 2.

[0017] The engine 12 is configured as an internal combustion engine that outputs power using fuel such as gasoline or diesel supplied from a fuel tank 11. The engine 12 has a port injection valve 28 that injects fuel into an intake port, an in-cylinder injection valve 29 that injects fuel into a combustion chamber 31, and an ignition plug 32. The in-cylinder injection valve 29 is disposed approximately at the center of the top of the combustion chamber 31 and injects fuel in a spray form. The ignition plug 32 is disposed near the in-cylinder injection valve 29 so as to be able to ignite the fuel sprayed in a spray form from the in-cylinder injection valve 29. The engine 12 has the port injection valve 28 and the in-cylinder injection valve 29, and is therefore capable of operating in any one of a port injection mode, an in-cylinder injection mode, and a common injection mode. In the port injection mode, air purified by the air cleaner 22 is drawn into the intake pipe 23 and passes through the intercooler 25, the throttle valve 26, and the surge tank 27 in that order, and fuel is injected from the port injection valve 28 downstream of the surge tank 27 of the intake pipe 23 to mix the air and fuel. This mixture is drawn into the combustion chamber 31 through the intake valve 30, and is explosively combusted by an electric spark from the spark plug 32. The reciprocating motion of the piston 33, which is pushed down by the energy of the explosive combustion, is converted into the rotational motion of the crankshaft 14. In the in-cylinder injection mode, air is drawn into the combustion chamber 31 in the same manner as in the port injection mode, and fuel is injected from the in-cylinder injection valve 29 once or in multiple times during the intake stroke, compression stroke, or expansion stroke, and is explosively combusted by an electric spark from the spark plug 32 to obtain the rotational motion of the crankshaft 14. In particular, when fuel is injected during the expansion stroke, fuel injection from the in-cylinder injection valve 29 during the expansion stroke is synchronized with ignition from the spark plug 32 so that the spray-like fuel injected from the in-cylinder injection valve 29 can be ignited. In the shared injection mode, fuel is injected from the port injection valve 28 when air is drawn into the combustion chamber 31, and fuel is injected from the in-cylinder injection valve 29 once or multiple times during the intake stroke, compression stroke, or expansion stroke, and is exploded and burned by an electric spark from the spark plug 32 to generate rotational motion for the crankshaft 14.Exhaust discharged from the combustion chamber 31 to the exhaust pipe 35 via the exhaust valve 34 is discharged into the outside air via purification devices 37, 38 having catalysts (three-way catalysts) that purify harmful components such as carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NOx). A starter (not shown) that cranks the engine 12 and an alternator 48 that generates electricity using the power of the engine 12 are attached to the crankshaft 14. The alternator 48 supplies the generated electricity to a power line that supplies power from a battery (not shown) to a fan motor 38d, a water pump 38e, and the like of the engine cooling system 38.

[0018] The fuel supply device 16 includes a fuel tank 11, a feed pump 11p, a low-pressure supply pipe 17, a high-pressure pump 18, and a high-pressure supply pipe 19. Fuel from the fuel tank 11 is pumped by the feed pump 11p and supplied to the port injection valve 28 via the low-pressure supply pipe 17. The feed pump 11p is configured as an electric pump that operates by receiving power from a battery (not shown), and is disposed in the fuel tank 11. Although not shown, the low-pressure supply pipe 17 is also provided with a check valve that allows fuel to flow in the direction from the feed pump 11p side to the port injection valve 28 side and regulates fuel flow in the opposite direction. In addition, the fuel from the low-pressure supply pipe 17 is pumped by the high-pressure pump 18 and supplied to the in-cylinder injection valve 29 via the high-pressure supply pipe 19. The high-pressure pump 18 is configured as a pump driven by power from the engine 12 (in the embodiment, the rotation of the intake camshaft that opens and closes the intake valve 30). The high-pressure pump 18 has an electromagnetic valve 18a connected to its intake port which opens and closes when pressurizing the fuel, a check valve 18b connected to its discharge port which regulates the backflow of fuel and maintains the fuel pressure in the high-pressure supply pipe 19, and a plunger 18c which operates by the rotation (rotation of the intake camshaft) of the engine 12. When the electromagnetic valve 18a is opened while the engine 12 is running, the high-pressure pump 18 sucks in fuel from the low-pressure supply pipe 17, and when the electromagnetic valve 18a is closed, the fuel compressed by the plunger 18c is intermittently sent to the high-pressure supply pipe 19 via the check valve 18b, thereby pressurizing the fuel to be supplied to the high-pressure supply pipe 19. Note that when the high-pressure pump 18 is driven, the fuel pressure in the low-pressure supply pipe 17 and the fuel pressure (fuel pressure) in the high-pressure supply pipe 19 pulsate in response to the rotation of the engine 12 (rotation of the intake camshaft).

[0019] The engine 12 is provided with an engine cooling system 38 that cools the engine 12 with a heat exchange medium (cooling water, etc.). The engine cooling system 38 includes a circulation flow path 38a that circulates the heat exchange medium between a water jacket (not shown) of the engine 12 and a radiator 38b. A fan 38c driven by a fan motor 38d is attached to the radiator 38b, and the internal heat exchange medium (water, etc.) is cooled by outside air. A water pump 38e that circulates the heat exchange medium is attached to the circulation flow path 38a.

[0020] The supercharger 40 is configured as a turbocharger, and includes a compressor 41, a turbine 42, a rotating shaft 43, a wastegate valve 44, and a blow-off valve 45. The compressor 41 is disposed upstream of the intercooler 25 in the intake pipe 23. The turbine 42 is disposed upstream of the purification device 37 in the exhaust pipe 35. The rotating shaft 43 connects the compressor 41 and the turbine 42. The wastegate valve 44 is provided in a bypass pipe 36 that connects the upstream side and downstream side of the turbine 42 in the exhaust pipe 35, and is controlled by an electronic control unit 70. The blow-off valve 45 is provided in a bypass pipe 24 that connects the upstream side and downstream side of the compressor 41 in the intake pipe 23, and is controlled by the electronic control unit 70.

[0021] In this turbocharger 40, the opening degree of the wastegate valve 44 is adjusted to adjust the distribution ratio between the amount of exhaust gas flowing through the bypass pipe 36 and the amount of exhaust gas flowing through the turbine 42, thereby adjusting the rotational driving force of the turbine 42, adjusting the amount of air compressed by the compressor 41, and adjusting the supercharging pressure (intake pressure) of the engine 12. In detail, the distribution ratio is adjusted so that the smaller the opening degree of the wastegate valve 44, the smaller the amount of exhaust gas flowing through the bypass pipe 36 and the larger the amount of exhaust gas flowing through the turbine 42. When the wastegate valve 44 is fully open, the engine 12 can operate in the same manner as a naturally aspirated engine without the turbocharger 40.

[0022] In addition, in the turbocharger 40, when the pressure downstream of the compressor 41 in the intake pipe 23 is somewhat higher than the pressure upstream of the intake pipe 23, the blow-off valve 45 is opened to release the excess pressure downstream of the compressor 41. Note that, instead of a valve controlled by the electronic control unit 70, the blow-off valve 45 may be configured as a check valve that opens when the pressure downstream of the compressor 41 in the intake pipe 23 becomes somewhat higher than the pressure upstream of the intake pipe 23.

[0023] The electronic control unit 70 is configured as a microprocessor with a CPU at its core, and in addition to the CPU, is equipped with a ROM for storing processing programs, a RAM for temporarily storing data, a non-volatile flash memory for storing and holding data, an input / output port, and a communication port. Signals from various sensors are input to the electronic control unit 70 via the input ports.

[0024] Examples of signals input to the electronic control unit 70 include a tank internal pressure Ptnk from an internal pressure sensor 11a that detects the pressure inside the fuel tank 11, a crank angle θcr from a crank position sensor 14a that detects the rotational position of the crankshaft 14 of the engine 12, a coolant temperature Tw from a water temperature sensor 38f that detects the temperature of the coolant for the engine 12, and a throttle opening TH from a throttle position sensor 26a that detects the opening of the throttle valve 26. Another example of signals input to the electronic control unit 70 is a cam position θca from a cam position sensor (not shown) that detects the rotational positions of an intake camshaft that opens and closes the intake valve 30 and an exhaust camshaft that opens and closes the exhaust valve 34. Other examples include the intake air amount Qa from the air flow meter 23a attached upstream of the compressor 41 of the intake pipe 23, the intake air temperature Tin from the intake air temperature sensor 23t attached upstream of the compressor 41 of the intake pipe 23, the intake pressure (pre-compressor pressure) Pin from the intake pressure sensor 23b attached upstream of the compressor 41 of the intake pipe 23, and the boost pressure Pc from the boost pressure sensor 23c attached between the compressor 41 of the intake pipe 23 and the intercooler 25. Other examples include the surge pressure (post-throttle pressure) Ps from the surge pressure sensor 27a attached to the surge tank 27, and the surge temperature Ts from the temperature sensor 27b attached to the surge tank 27. Other examples include the low-pressure fuel pressure Pfp from the fuel pressure sensor 28a that detects the pressure of the fuel supplied to the port injection valve 28, and the high-pressure fuel pressure Pfd from the fuel pressure sensor 29a that detects the pressure of the fuel supplied to the in-cylinder injection valve 29. Examples of the front air-fuel ratio AF1 from a front air-fuel ratio sensor 35a attached upstream of the purification device 37 of the exhaust pipe 35, and a rear air-fuel ratio AF2 from a rear air-fuel ratio sensor 35b attached downstream of the purification device 37 of the exhaust pipe 35 can also be mentioned.

[0025] Various control signals are output from the electronic control unit 70 via the output port. Examples of signals output from the electronic control unit 70 include a control signal to the alternator 15, a control signal to the throttle valve 26, a control signal to the port injection valve 28, a control signal to the in-cylinder injection valve 29, and a control signal to the spark plug 32. Examples of the signals output from the electronic control unit 70 include a drive signal to the fan motor 38d and the water pump 38e of the engine cooling device 38, and a drive signal to the fan motor 39d and the circulation pump 39e of the intercooler cooling device 39. Examples of the signals include a control signal to the wastegate valve 44, a control signal to the blow-off valve 45, and a control signal to the solenoid valve 18a.

[0026] The electronic control unit 70 calculates the rotation speed Ne and the load factor KL (the ratio of the volume of air actually taken in one cycle to the stroke volume per cycle of the engine 12) of the engine 12. The rotation speed Ne is calculated based on the crank angle θcr from the crank position sensor 14a. The load factor KL is calculated based on the amount of intake air Qa from the air flow meter 23a and the rotation speed Ne.

[0027] In the engine system 10 of this embodiment configured as described above, the electronic control unit 70 performs intake air amount control that controls the opening of the throttle valve 26, fuel injection control that controls the amount of fuel injected from the in-cylinder injection valve 28, ignition control that controls the ignition timing of the spark plug 31, supercharging control that controls the opening of the wastegate valve 44, and fuel pressure control in the high-pressure supply pipe 19 by opening and closing the solenoid valve 18a, based on the required load rate KL* of the engine 12.

[0028] Next, the operation of the engine device 10 of the embodiment, particularly the operation when removing deposits that adhere to and accumulate near the tip of the in-cylinder injection valve 29, will be described. FIG. 3 is a flowchart showing an example of a deposit removal process executed by the electronic control unit 70. FIG. 4 is a flowchart showing an example of a first counter process executed by the electronic control unit 70, and FIG. 5 is a flowchart showing an example of a second counter process executed by the electronic control unit 70. The deposit removal process of FIG. 3 is performed based on a first removal flag Fcs set by the first counter CS and a second removal flag Fch set by the second counter Ch. For ease of explanation, the first counter process and the second counter process will be described first, and then the deposit removal process will be described.

[0029] 4 is repeatedly executed for each cycle (720 crank angles). When the first counter process is executed, the electronic control unit 70 first inputs data required for the first counter process, such as the temperature (coolant temperature) Tw of the engine 12 detected by the temperature sensor 38f and the fuel pressure Pfd of the high-pressure supply pipe 19 detected by the fuel pressure sensor 29a (step S200).

[0030] When the data is input, a count-up process (steps S210 to S240) of the first counter Cs is executed. In the count-up process of the first counter Cs, first, it is determined whether or not the cooling water temperature Tw is equal to or higher than a threshold value Tref1 (step S210). The threshold value Tref1 is a threshold value for determining whether or not the engine 12 is in a state where it has been warmed up to a certain degree, and for example, 50°C, 60°C, or 70°C can be used. Since the first counter process is executed when the engine 12 has been warmed up to a certain degree, if it is determined that the cooling water temperature Tw is less than the threshold value Tref1, the process is terminated without counting up or down the first counter Cs.

[0031] When it is determined in step S210 that the cooling water temperature Tw is equal to or higher than the threshold value Tref1, it is then determined whether or not the high-pressure side fuel pressure Pfd is less than the threshold value Pref1 (step S220). The threshold value Pref1 can be a lower limit fuel pressure at which thermoplastic deposits adhering to and accumulating near the tip of the direct injection valve 29 can be removed, and can be, for example, 11 MPa, 12 MPa, or 13 MPa. Therefore, when it is determined that the high-pressure side fuel pressure Pfd is equal to or higher than the threshold value Pref1, it is considered that thermoplastic deposits will not adhere to and accumulate near the tip of the direct injection valve 29.

[0032] When it is determined in step S220 that the high pressure side fuel pressure Pfd is less than the threshold Pref1, it is determined whether or not the fuel injection from the port injection valve 28 is 100%, that is, whether or not there is no fuel injection from the direct injection valve 29 (step S230). This is because it is considered that when fuel is injected from the direct injection valve 29, adhesion and accumulation of thermoplastic deposits near the tip of the direct injection valve 29 does not occur.

[0033] When it is determined in step S230 that the fuel injection from the port injection valve 28 is 100%, the first counter Cs is incremented by a value of 1 (step S240). Note that when it is determined in step S210 that the cooling water temperature Tw is less than the threshold value Tref1, when it is determined in step S220 that the high-pressure side fuel pressure Pfd is equal to or greater than the threshold value Pref1, or when it is determined in step S230 that the fuel injection from the port injection valve 28 is not 100%, the first counter Cs is not incremented. A list of counting processing conditions for the first counter Cs in the embodiment is shown in FIG. 6. In this counting processing, the first counter Cs is incremented by a value of 1, assuming that the cooling water temperature Tw is equal to or greater than the threshold value Tref, when both of the conditions that the high-pressure side fuel pressure Pfd is less than the threshold value Pref1 and that the fuel injection from the port injection valve 28 is 100% are satisfied.

[0034] After the count-up process of the first counter Cs is performed, the count-down process of the first counter Cs (steps S250 to S290) is performed. In the count-down process of the first counter Cs, first, it is determined whether the high-pressure side fuel pressure Pfd is equal to or greater than the threshold value Pref1 (step S250). This is because it is considered that if the high-pressure side fuel pressure Pfd is less than the threshold value Pref1, the thermoplastic deposits that have adhered and accumulated near the tip of the in-cylinder injection valve 29 cannot be removed.

[0035] When it is determined in step S250 that the high pressure side fuel pressure Pfd is equal to or greater than the threshold Pref1, it is determined whether or not the fuel injection from the port injection valve 28 is other than 100%, that is, whether or not fuel injection from the direct injection valve 29 has been performed (step S260). This is because it is considered that the injection of fuel from the direct injection valve 29 can remove thermoplastic deposits that have built up near the tip of the direct injection valve 29.

[0036] When it is determined in step S260 that the fuel injection from the port injection valve 28 is other than 100%, a first down amount ΔCs for counting down the first counter Cs is derived based on the high-pressure fuel pressure Pfd (step S270). In this embodiment, the relationship between the high-pressure fuel pressure Pfd and the first down amount ΔCs is determined in advance and stored as a first down amount setting map, and when the high-pressure fuel pressure Pfd is given, the corresponding first down amount ΔCs is derived from the map. FIG. 7 shows an example of the first down amount setting map. As shown in the figure, the first down amount ΔCs is set to a value of 2 when the high-pressure fuel pressure Pfd is the threshold Pref1, and is set to increase as the high-pressure fuel pressure Pfd increases within a range equal to or greater than the threshold Pref1. The first down amount setting map is stepped in order to set the first down amount ΔCs to an integer.

[0037] When the first reduction amount ΔCs is derived, the first counter Cs is subtracted from the first counter Cs to set a new first counter Cs (step S280), and the set first counter Cs is guarded against a lower limit by a value of 0 (step S290). As a result, the first counter Cs is counted down to a value of 0 or more. Note that when it is determined in step S250 that the high-pressure side fuel pressure Pfd is less than the threshold value Pref1, or when it is determined in step S260 that the fuel injection from the port injection valve 28 is not other than 100% (is 100%), the first counter Cs is not counted down. In this countdown process, when both the condition that the high-pressure side fuel pressure Pfd is equal to or greater than the threshold value Pref1 and the condition that the fuel injection from the port injection valve 28 is not 100% (the condition that the fuel is injected from the in-cylinder injection valve 29) are satisfied, the first counter Cs is counted down by the first reduction amount ΔCs.

[0038] After the count-up and count-down processes of the first counter Cs are thus performed, a setting process of the first removal flag Fcs (steps S300 to S330) is performed. In the setting process of the first removal flag Fcs, first, it is determined whether the first counter Cs is equal to or greater than a threshold value Cref1 (step S300). The first removal flag Fcs is set to a value of 0 as an initial value, and is set to a value of 1 when a request is made to remove a thermoplastic deposit that has adhered and accumulated near the tip of the in-cylinder injection valve 29, and is set to a value of 0 when the removal of the deposit is completed. The threshold value Cref1 is a threshold value for determining whether or not it is necessary to remove a thermoplastic deposit that has adhered and accumulated near the tip of the in-cylinder injection valve 29, and can be determined by experiments or the like according to the characteristics of the engine 12. When it is determined that the first counter Cs is equal to or greater than the threshold value Cref1, the first removal flag Fcs is set to a value of 1 (step S310).

[0039] Next, it is determined whether the first counter Cs is equal to 0 (step S320), and if it is determined that the first counter Cs is equal to 0, the first removal flag Fcs is set to 0 (step S330), and this process ends. When the first counter Cs is equal to or greater than 1 and less than the threshold Cref1, the first removal flag Fcs maintains its value. The first removal flag Fcs is set to 1 when the first counter Cs, which counts up and down by the first counter process of Fig. 4, reaches equal to or greater than the threshold Cref1, and is set to 0 when the first counter Cs is equal to 0.

[0040] The second counter process in Fig. 5 is repeatedly executed for each cycle (720 crank angles). When the second counter process is executed, the electronic control unit 70 first inputs data required for the second counter process, such as the cooling water temperature Tw detected by the temperature sensor 38f, the high-pressure fuel pressure Pfd detected by the fuel pressure sensor 29a, and the tip temperature Test of the in-cylinder injection valve 29 (step S400). The tip temperature Test of the in-cylinder injection valve 29 is estimated to be higher as the intake air amount Qa is larger and the cooling water temperature Tw is higher. Based on this, in the embodiment, the relationship between the intake air amount Qa, the cooling water temperature Tw, and the tip temperature Test is obtained in advance and stored as a tip temperature setting map, and when the intake air amount Qa and the cooling water temperature Tw are given, the tip temperature Test corresponding to the intake air amount Qa and the cooling water temperature Tw is derived from the map to estimate the tip temperature Test, so this is input.

[0041] When the data is input, it is determined whether the cooling water temperature Tw is equal to or higher than the threshold value Tref1 (step S410). The threshold value Tref1 has been described above. If it is determined that the cooling water temperature Tw is lower than the threshold value Tref1, this process ends without counting up or down the first counter Cs.

[0042] When it is determined in step S410 that the cooling water temperature Tw is equal to or greater than the threshold value Tref1, a count-up process (steps S420 to S460) is executed. In the count-up process of the second counter Ch, first, it is determined whether or not the tip temperature Test of the in-cylinder injection valve 29 is equal to or greater than the threshold value Tref2 (step S420). The threshold value Tref2 is determined as the lower limit temperature of the temperature range at which a thermosetting deposit is likely to adhere and accumulate near the tip of the in-cylinder injection valve 29 or a temperature in the vicinity thereof, and for example, 140°C, 150°C, 160°C, etc. can be used. When it is determined that the tip temperature Test of the in-cylinder injection valve 29 is equal to or greater than the threshold value Tref2, it is determined whether or not the fuel injection from the port injection valve 28 is 100% (step S430), and when it is determined that the fuel injection from the port injection valve 28 is 100%, the second counter Ch is counted up by a value of 1 (step S460).

[0043] When it is determined in step S420 that the tip temperature Test of the in-cylinder injection valve 29 is less than the threshold value Tref2, it is determined whether or not the high-pressure side fuel pressure Pfd is less than the threshold value Pref2 (step S440). The threshold value Pref2 can be a lower limit fuel pressure at which a thermosetting deposit adhering and accumulating near the tip of the in-cylinder injection valve 29 can be removed, for example, 18 MPa, 20 MPa, 22 MPa, etc. can be used. Therefore, when it is determined that the high-pressure side fuel pressure Pfd is equal to or greater than the threshold value Pref2, it is considered that a thermosetting deposit will not adhere and accumulate near the tip of the in-cylinder injection valve 29. When it is determined that the high-pressure side fuel pressure Pfd is less than the threshold value Pref2, it is determined whether or not the fuel injection from the port injection valve 28 is 100% (whether or not fuel is being injected from the in-cylinder injection valve 29) (step S450). This determination is based on the assumption that, when fuel is being injected from the in-cylinder injection valve 29, thermosetting deposits do not adhere to and accumulate near the tip of the in-cylinder injection valve 29. If it is determined that the fuel injection from the port injection valve 28 is not 100%, the second counter Ch is counted up by a value of 1 (step S460).

[0044] When it is determined in step S430 that the fuel injection from the port injection valve 28 is not 100%, when it is determined in step S440 that the high-pressure side fuel pressure Pfd is equal to or greater than the threshold value Pref2, or when it is determined in step S450 that the fuel injection from the port injection valve 29 is 100%, the second counter Ch is not counted up. A list of count processing conditions for the second counter Ch in the embodiment is shown in Fig. 8. In this count-up processing, the cooling water temperature Tw is a prerequisite that it is equal to or greater than the threshold value Tref, and when both of the conditions that the tip temperature of the in-cylinder injection valve 29 is equal to or greater than the threshold value Tref2 and that the high-pressure side fuel pressure Pfd is less than the threshold value Pref2 are satisfied, the second counter Ch is counted up by a value of 1.

[0045] After the count-up process of the second counter Ch is performed, the count-down process of the second counter Ch (steps S470 to S510) is performed. In the count-down process of the second counter Ch, first, it is determined whether the high-pressure side fuel pressure Pfd is equal to or greater than the threshold value Pref2 (step S470). This is because it is considered that if the high-pressure side fuel pressure Pfd is less than the threshold value Pref2, the thermosetting deposits that have adhered and accumulated near the tip of the in-cylinder injection valve 29 cannot be removed.

[0046] When it is determined in step S470 that the high pressure side fuel pressure Pfd is equal to or greater than the threshold Pref2, it is determined whether or not the fuel injection from the port injector 28 is other than 100%, that is, whether or not fuel injection from the direct injection valve 29 has been performed (step S480). This is because it is considered that fuel injection from the direct injection valve 29 can remove thermosetting deposits that have built up near the tip of the direct injection valve 29.

[0047] When it is determined in step S480 that the fuel injection from the port injection valve 28 is other than 100%, the second down amount ΔCh for counting down the second counter Ch is derived based on the high-pressure fuel pressure Pfd (step S490). In this embodiment, the relationship between the high-pressure fuel pressure Pfd and the second down amount ΔCh is determined in advance and stored as a second down amount setting map, and when the high-pressure fuel pressure Pfd is given, the corresponding second down amount ΔCh is derived from the map. FIG. 9 shows an example of the second down amount setting map. As shown in the figure, the second down amount ΔCh is set to a value of 6 when the high-pressure fuel pressure Pfd is the threshold Pref2, and is set to increase as the high-pressure fuel pressure Pfd increases within a range equal to or greater than the threshold Pref2. The second down amount setting map is stepped in order to set the second down amount ΔCh to an integer.

[0048] When the second reduction amount ΔCh is derived, the second counter Ch is subtracted by the second reduction amount ΔCh to set a new second counter Ch (step S500), and the set second counter Ch is guarded against a lower limit by a value of 0 as a lower limit value (step S510). As a result, the second counter Ch is counted down to a value of 0 or more. Note that when it is determined in step S470 that the high-pressure side fuel pressure Pfd is less than the threshold value Pref2, or when it is determined in step S480 that the fuel injection from the port injection valve 28 is not other than 100% (is 100%), the second counter Ch is not counted down. In this countdown process, when all of the conditions that the high-pressure side fuel pressure Pfd is equal to or greater than the threshold value Pref2 and that the fuel injection from the port injection valve 28 is not 100% (the condition that the fuel is injected from the in-cylinder injection valve 29) are satisfied, the second counter Ch is counted down by the second reduction amount ΔCh.

[0049] After the count-up and count-down processes of the second counter Ch are thus performed, a setting process of the second removal flag Fch (steps S520 to S550) is performed. In the setting process of the second removal flag Fch, first, it is determined whether the second counter Ch is equal to or greater than a threshold value Cref2 (step S520). The second removal flag Fch is set to a value of 0 as an initial value, and is set to a value of 1 when a request is made to remove a thermosetting deposit that has adhered and accumulated near the tip of the in-cylinder injection valve 29, and is set to a value of 0 when the removal of the deposit is completed. The threshold value Cref2 is a threshold value for determining whether or not it is necessary to remove a thermosetting deposit that has adhered and accumulated near the tip of the in-cylinder injection valve 29, and can be determined by experiments or the like according to the characteristics of the engine 12. When it is determined that the second counter Ch is equal to or greater than the threshold value Cref2, the second removal flag Fch is set to a value of 1 (step S530).

[0050] Next, it is determined whether the second counter Ch has a value of 0 (step S540), and if it is determined that the second counter Ch has a value of 0, the second removal flag Fch is set to a value of 0 (step S550), and this process ends. When the second counter Ch has a value of 1 or more and is less than the threshold value Cref2, the second removal flag Fch maintains its value. The second removal flag Fch is set to a value of 1 when the second counter Ch, which counts up and down by the second counter process of Fig. 5, reaches a value equal to or greater than the threshold value Cref2, and is set to a value of 0 when the second counter Ch has a value of 0.

[0051] Next, the deposit removal process of Fig. 3 will be described. When the deposit removal process is executed, the electronic control unit 70 first inputs the first removal flag Fcs and the second removal flag Fch (step S100). Next, it is determined whether the first removal flag Fcs is set to a value of 1 and the second removal flag Fch is set to a value of 0 (step S110). Since the first removal flag Fcs is set to a value of 1 when it is necessary to remove thermoplastic deposits and the second removal flag Fch is set to a value of 1 when it is necessary to remove thermosetting deposits, the determination in step S110 is whether it is necessary to remove thermoplastic deposits while it is not yet necessary to remove thermosetting deposits.

[0052] When it is determined in step S110 that the first removal flag Fcs is equal to 1 and the second removal flag Fch is equal to 0, it is then determined whether or not conditions exist for allowing the deposit removal process to be performed (step S120). Such conditions may include the vehicle being stopped, or the engine 12 having finished warming up, etc.

[0053] When it is determined in step S120 that the conditions for performing the deposit removal process are met, the high-pressure pump 18 is driven so that the high-pressure fuel pressure Pfd becomes the threshold value Pref1, and fuel is injected from the in-cylinder injection valve 29 at 100% (step S130). By injecting fuel from the in-cylinder injection valve 29 with the high-pressure fuel pressure Pfd set to the threshold value Pref1, the thermoplastic deposits that have adhered and accumulated near the tip of the in-cylinder injection valve 29 are removed. Note that this removal process (first removal process) in step S130 continues until the first counter Cs becomes 0 and the first removal flag Fcs is set to 0. Note that if the driver depresses the accelerator pedal during the first removal process and the conditions for performing the deposit removal process are no longer met, the first removal process is interrupted, but is resumed when the conditions for performing the deposit removal process are subsequently met.

[0054] Next, it is determined whether the second removal flag Fch is equal to the value 1 (step S140). When it is determined that the second removal flag Fch is equal to the value 1, it is determined whether the conditions for performing the deposit removal process are satisfied (step S150). These conditions are the same as those in the first removal process. When it is determined that the conditions for performing the deposit removal process are satisfied, the high-pressure pump 18 is driven so that the high-pressure side fuel pressure Pfd becomes the threshold value Pref2, and fuel is injected from the in-cylinder injection valve 29 at 100% (step S160). By injecting fuel from the in-cylinder injection valve 29 with the high-pressure side fuel pressure Pfd set to the threshold value Pref2, the thermosetting deposits that have adhered and accumulated near the tip of the in-cylinder injection valve 29 are removed. In this removal process of step S160 (second removal process), the high pressure side fuel pressure Pfd is set to a threshold value Pref2 which is greater than the threshold value Pref1, so that not only thermosetting deposits are removed but also thermoplastic deposits are removed. The second removal process continues until the second counter Ch reaches a value of 0 and the second removal flag Fch is set to a value of 0. If the driver depresses the accelerator pedal while the second removal process is being performed and the conditions for performing the deposit removal process are no longer met, the second removal process is interrupted, but is resumed when the conditions for performing the deposit removal process are subsequently met.

[0055] 3, the second removal process is executed regardless of the value of the first removal flag Fcs when the second removal flag Fch has a value of 1. The first removal process is executed when the second removal flag Fch has a value of 0 and the first removal flag Fcs has a value of 1.

[0056] In the engine device 10 of the embodiment described above, when the first counter Cs reflecting the amount of thermoplastic deposits adhering and accumulating near the tip of the in-cylinder injection valve 29 reaches or exceeds the threshold value Cref1, the fuel pressure Pfd of the high-pressure supply pipe 19 is set to or above the threshold value Pref1 and fuel is injected from the in-cylinder injection valve 29 to perform a thermoplastic deposit removal process (first removal process). When the second counter Ch reflecting the amount of thermosetting deposits adhering and accumulating near the tip of the in-cylinder injection valve 29 reaches or exceeds the threshold value Cref2, the fuel pressure Pfd of the high-pressure supply pipe 19 is set to or above the threshold value Pref2 and fuel is injected from the in-cylinder injection valve 29 to perform a thermosetting deposit removal process (second removal process). In this way, by performing the thermoplastic deposit removal process and the thermosetting deposit removal process using the first counter Cs and the second counter Ch, the deposits accumulated in the in-cylinder injection valve 29 can be more appropriately removed.

[0057] In the engine device 10 of the embodiment, the first counter process counts up by a value of 1, but it may also be configured to count up by a value of 2, or to count up using a first increment amount that changes according to the cooling water temperature Tw or the high-pressure side fuel pressure Pfd. Also, in the second counter process, the second counter process counts up by a value of 1, but it may also be configured to count up by a value of 2, or to count up using a second increment amount that changes according to the tip temperature Test or the fuel injection rate from the port injection valve 28.

[0058] In the engine device 10 of the embodiment, the first counter process counts down using a first down amount ΔCs that increases as the high-pressure fuel pressure Pfd increases, but a fixed first down amount may be used. In the second counter process, the second counter process counts down using a second down amount ΔCh that increases as the high-pressure fuel pressure Pfd increases, but a fixed second down amount may be used.

[0059] In the engine device 10 of the embodiment, the condition for counting up the first counter Cs is that the condition that fuel injection from the port injection valve 28 is 100% is satisfied with the precondition that the cooling water temperature Tw is equal to or higher than the threshold value Tref1, but the condition that the tip temperature Test of the direct injection valve 29 is equal to or higher than the threshold value Tref2 is satisfied with the precondition that the cooling water temperature Tw is equal to or higher than the threshold value Tref1 may also be used. Since the second counter Ch is counted up when the condition that the tip temperature Test of the direct injection valve 29 is equal to or higher than the threshold value Tref2 is satisfied with the precondition that the cooling water temperature Tw is equal to or higher than the threshold value Tref1, the first counter Cs is also counted up to be on the safe side.

[0060] In the engine device 10 of the embodiment, the engine 12 used has an in-cylinder injection valve 29 arranged approximately in the center of the top of the combustion chamber 31, but it is also possible to use an engine in which the in-cylinder injection valve 29 is arranged on the side wall (side) of the combustion chamber 31.

[0061] In the engine system 10 of the embodiment, the supercharger 40 is configured as a turbocharger in which a compressor 41 arranged in the intake pipe 23 and a turbine 42 arranged in the exhaust pipe 35 are connected via a rotating shaft 43. However, instead of this, the supercharger may be configured as a compressor driven by the engine 12 or a motor and arranged in the intake pipe 23. Also, the supercharger 40 may not be provided.

[0062] The correspondence between the main elements of the embodiment and the main elements of the invention described in the section on Means for Solving the Problems will be described below. In the embodiment, the port injection valve 28 corresponds to the "port injection valve", the in-cylinder injection valve 29 corresponds to the "in-cylinder injection valve", the engine 12 corresponds to the "engine", the fuel tank 11 corresponds to the "fuel tank", the feed pump 11p corresponds to the "low pressure pump", the high pressure pump 18 corresponds to the "high pressure pump", the fuel supply device 16 corresponds to the "fuel supply device", and the electronic control unit 70 corresponds to the "control device".

[0063] The correspondence between the main elements of the Examples and the main elements of the invention described in the Summary of the Problem column does not limit the elements of the invention described in the Summary of the Problem column, since the Examples are examples for specifically explaining the mode for implementing the invention described in the Summary of the Problem column. In other words, the interpretation of the invention described in the Summary of the Problem column should be based on the description in that column, and the Examples are merely a specific example of the invention described in the Summary of the Problem column.

[0064] Although the form for carrying out the present invention has been described above using examples, the present invention is not limited to these examples in any way, and it goes without saying that the present invention can be carried out in various forms without departing from the scope of the gist of the present invention. [Industrial Applicability]

[0065] The present invention can be used in the engine device manufacturing industry and the like. [Explanation of symbols]

[0066] 10 engine device, 11 fuel tank, 11a internal pressure sensor, 11p feed pump, 12 engine, 14 crankshaft, 14a crank position sensor, 16 fuel supply device, 17 low pressure supply pipe, 18 high pressure pump, 18a solenoid valve, 18b check valve, 18c plunger, 19 high pressure supply pipe, 22 air cleaner, 23 intake pipe, 23a air flow meter, 23b intake pressure sensor, 23c boost pressure sensor, 24 bypass pipe, 25 intercooler, 26 throttle valve, 26a throttle position sensor, 27 surge tank, 27a surge pressure sensor, 27b temperature sensor, 28 in-cylinder injection valve, 28a fuel pressure sensor, 29 intake valve, 30 combustion chamber, 31 spark plug, 32 piston, 34 exhaust valve, 35 exhaust pipe, 35a Front air-fuel ratio sensor, 35b rear air-fuel ratio sensor, 36 bypass pipe, 37 purification device, 38 engine cooling system, 38a circulation flow path, 38b radiator, 38c fan, 38d fan motor, 38e water pump, 38f temperature sensor, 40 turbocharger, 41 compressor, 42 turbine, 43 rotating shaft, 44 wastegate valve, 45 blow-off valve, 70 electronic control unit.

Claims

1. an engine having a port injection valve and a direct injection valve; a fuel supply device including a low-pressure pump that pressure-feeds fuel from a fuel tank to a low-pressure supply pipe to which the port injection valve is connected, and a high-pressure pump that pressure-feeds fuel from the low-pressure supply pipe to a high-pressure supply pipe to which the in-cylinder injection valve is connected; a control device for controlling the engine and the fuel supply device; An engine device comprising: The control device includes: when a first counter, which is incremented when the fuel pressure in the high-pressure supply pipe is less than a first predetermined pressure, reaches a first threshold value or more, a first removal process is performed in which the fuel pressure in the high-pressure supply pipe is set to a state equal to or greater than the first predetermined pressure, fuel is injected from the in-cylinder injection valve, and deposits accumulated in the in-cylinder injection valve are removed; when a second counter, which is incremented when the fuel pressure in the high-pressure supply pipe is less than a second predetermined pressure higher than the first predetermined pressure and the tip temperature of the in-cylinder injection valve is equal to or higher than a predetermined temperature, reaches a second threshold value or more, a second removal process is performed in which the fuel pressure in the high-pressure supply pipe is set to a state equal to or higher than the second predetermined pressure, fuel is injected from the in-cylinder injection valve, and deposits accumulated in the in-cylinder injection valve are removed. An engine device characterized by:

2. 2. The engine device according to claim 1, the control device increments the first counter and the second counter when the engine cooling water temperature is equal to or higher than a predetermined water temperature and the tip temperature of the in-cylinder injection valve is equal to or higher than the predetermined temperature. Engine equipment.

3. 2. The engine device according to claim 1, the first counter is increased by a first increase amount when fuel injection is performed from the port injection valve with the fuel pressure in the high-pressure supply pipe being lower than the first predetermined pressure in a state in which the cooling water temperature of the engine is equal to or higher than a predetermined water temperature, and is decreased by a first decrease amount when fuel injection is performed from the direct injection valve with the fuel pressure in the high-pressure supply pipe being equal to or higher than the first predetermined pressure, the second counter is increased by a second increase amount when fuel injection is performed from the port injection valve and / or the in-cylinder injection valve in a state where the cooling water temperature of the engine is equal to or higher than the predetermined water temperature, the fuel pressure in the high-pressure supply pipe is lower than the second predetermined pressure, the tip temperature of the in-cylinder injection valve is equal to or higher than the predetermined temperature, and is decreased by a second decrease amount when fuel injection is performed from the in-cylinder injection valve in a state where the fuel pressure in the high-pressure supply pipe is equal to or higher than the second predetermined pressure. Engine equipment.

4. 4. The engine device according to claim 3, the first increase amount and the second increase amount are equal to 1; the first down amount becomes larger as the fuel pressure in the high-pressure supply pipe becomes larger within a range equal to or higher than the first predetermined pressure, the second down amount increases as the fuel pressure in the high-pressure supply pipe increases within a range equal to or higher than the second predetermined pressure; Engine equipment.

5. The engine device according to claim 3 or 4, the first removal process is terminated when the first counter reaches a value of 0; The second removal process ends when the second counter reaches a value of 0. The engine device.

6. 6. The engine device according to claim 5, the first removal process and the second removal process are executed when the power required for the engine is less than a predetermined power, and are interrupted when the power required for the engine is equal to or greater than the predetermined power. Engine equipment.

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