JP7605068B2 - Engine equipment - Google Patents

Description

The present invention relates to an engine device, and more specifically, to an engine device equipped with an engine having a port injection valve and an in-cylinder injection valve.

Conventionally, engine devices of this type have been proposed that include a port injection valve that injects fuel into the intake port and an in-cylinder injection valve that injects fuel into the combustion chamber (see, for example, Patent Document 1). In this device, if it is determined that the injection period of in-cylinder injection is shorter than a predetermined minimum injection period that has been set in advance, in-cylinder injection is prohibited for that injection period, and the port injection ratio is increased to make up for the shortfall in the fuel injection amount caused by the prohibition of in-cylinder injection. This allows stable engine operation even if the injection period of in-cylinder injection is shorter than the minimum injection period for some reason.

JP 2014-231742 A

However, in the above-mentioned engine device, when fuel is injected from the in-cylinder injection valve and the engine is operated in the high-speed, high-torque range, the fuel injection period becomes long, and selecting the optimal injection start timing may result in the injection end timing exceeding the injection retard limit. In this case, it may be possible to guard the injection end timing with the injection retard limit and advance the injection start timing, but advancing the injection start timing may result in the timing being advanced beyond the combustion limit or the limit due to the rise in catalyst temperature caused by fuel blow-by due to scavenging.

The main purpose of the engine device of the present invention is to inject fuel more appropriately from the in-cylinder injection valve when the engine is operated in the high-speed, high-torque range.

The engine device of the present invention employs the following means to achieve the above-mentioned main objective.

The engine device of the present invention comprises:
an engine having a port injection valve that injects fuel into an intake port and an in-cylinder injection valve that injects fuel into a cylinder;
A control device for controlling the engine;
An engine device comprising:
when the engine is operated in a high rotation and high torque region by injecting fuel from the in-cylinder injection valve and the injection start timing determined by guarding the injection end timing with a retard guard defined as an injection retard limit is on the advanced side of an advance guard based on engine speed, load factor, and atmospheric pressure, the control device injects fuel from the port injection valve in an amount of fuel injection corresponding to a period of the fuel injection period that is longer than the period from the advance guard to the retard guard.
It is characterized by:

In the engine device of the present invention, when fuel is injected from the in-cylinder injection valve and the engine is operated in the high-speed, high-torque range, if the injection start time determined by guarding the injection end time with the retard guard set as the injection retard limit is more advanced than the advance guard based on the engine speed, load factor, and atmospheric pressure, the port injection valve injects a fuel injection amount corresponding to a period of the fuel injection period that is longer than the period from the advance guard to the retard guard. In other words, the port injection valve injects a fuel injection amount that is insufficient for the fuel injection period from the advance guard to the retard guard. This allows for more appropriate fuel injection even when the engine is operated in the high-speed, high-torque range and fuel is injected from the in-cylinder injection valve.

The advance guard is based on engine speed, load factor, and atmospheric pressure for the following reasons. The advance guard must be set so that the injection start timing does not fall within the scavenge region. The scavenge region is a suitable region with a large amount of overlap based on the opening and closing timing of the engine's intake and exhaust valves. Since the valve opening and closing timing is often determined by a two-dimensional map of engine speed and load factor, it is preferable to use a two-dimensional map of engine speed and load factor for the advance guard as well. In addition, since fuel blow-through due to scavenge is more likely to occur at lower atmospheric pressures, it is preferable to set the advance guard so that it tends to be more retarded as the atmospheric pressure decreases. As a result of these factors, it is preferable to determine the advance guard based on engine speed, load factor, and atmospheric pressure, and it is even more preferable to set it using a three-dimensional map of engine speed, load factor, and atmospheric pressure.

1 is a configuration diagram showing an outline of the configuration of an engine device 10 according to an embodiment of the present invention. 4 is a flowchart showing an example of in-cylinder injection control executed by an electronic control unit 70. 10 is an explanatory diagram showing a case example in which the injection start timing θst and the injection end timing θend are set by the in-cylinder injection control. FIG.

Next, we will explain how to implement the present invention using examples.

Figure 1 is a schematic diagram showing the configuration of an engine device 10 according to one embodiment of the present invention. As shown in the figure, the engine device 10 of the embodiment includes an engine 12, a fuel supply device 50, and an electronic control unit 70. This engine device 10 is mounted on a general vehicle that runs on power from the engine 12, various hybrid vehicles that include a motor in addition to the engine 12, and stationary equipment (such as construction equipment) that operates using power from the engine 12.

Engine 12 is configured as an internal combustion engine that uses fuel such as gasoline or a mixture of gasoline and alcohol, and outputs power through four strokes: intake, compression, expansion, and exhaust. This engine 12 is equipped with a port injection valve 25 that injects fuel into the intake port, and an in-cylinder injection valve 26 that injects fuel into the cylinder. By being equipped with the port injection valve 25 and the in-cylinder injection valve 26, engine 12 can be operated in any of a port injection mode, an in-cylinder injection mode, and a shared injection mode.

In the port injection mode, air cleaned by the air cleaner 22 is drawn into the intake pipe 23 and passed through the throttle valve 24, while fuel is injected from the port injection valve 25 to mix the air and fuel. This mixture is then drawn into the combustion chamber 29 via the intake valve 28, where it is explosively combusted by an electric spark from the spark plug 30. The reciprocating motion of the piston 32, 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 29 in the same way as in the port injection mode, and fuel is injected from the in-cylinder injection valve 26 midway through the intake stroke and/or at the compression stroke, and is explosively combusted by an electric spark from the spark plug 30 to obtain the rotational motion of the crankshaft 14. In the shared injection mode, fuel is injected from the port injection valve 25 when air is drawn into the combustion chamber 29, and from the in-cylinder injection valve 26 during the intake stroke and compression stroke, and the fuel is explosively burned by an electric spark from the spark plug 30 to obtain rotational motion of the crankshaft 14. These injection modes are switched according to the operating state of the engine 12. Exhaust exhaust discharged from the combustion chamber 29 to the exhaust pipe 33 through the exhaust valve 31 is discharged into the outside air through a purification device 34 having a purification catalyst (three-way catalyst) 34a that purifies harmful components such as carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NOx).

The fuel supply device 50 is configured as a device that supplies fuel in a fuel tank 51 to the port injection valves 25 and the in-cylinder injection valves 26 of the engine 12. The fuel supply device 50 includes a fuel tank 51, a feed pump (first pump) 52, a low-pressure supply pipe (first supply pipe) 53, a check valve 54, a relief flow passage 55, a relief valve 56, a high-pressure pump (second pump) 57, and a high-pressure supply pipe (second supply pipe) 58.

The feed pump 52 is configured as an electric pump that operates by receiving power from a battery (not shown), and is disposed in the fuel tank 51. This feed pump 52 supplies fuel in the fuel tank 51 to a low-pressure supply pipe 53. The low-pressure supply pipe 53 is connected to the port injection valve 25. A check valve 54 is provided in the low-pressure supply pipe 53, and allows fuel to flow from the feed pump 52 side to the port injection valve 25 side, while restricting fuel flow in the opposite direction.

The relief flow passage 55 is connected to the low-pressure supply pipe 53 and the fuel tank 51. The relief valve 56 is provided in the relief flow passage 55, and closes when the fuel pressure in the low-pressure supply pipe 53 is less than the threshold value Pflolim, and opens when the fuel pressure in the low-pressure supply pipe 53 is equal to or greater than the threshold value Pflolim. When the relief valve 56 opens, a portion of the fuel in the low-pressure supply pipe 53 is returned to the fuel tank 51 via the relief flow passage 55. In this way, the fuel pressure in the low-pressure supply pipe 53 is prevented from becoming excessive.

The high-pressure pump 57 is driven by power from the engine 12 (in the embodiment, the rotation of the intake camshaft that opens and closes the intake valve 28) and is configured as a pump that pressurizes the fuel in the low-pressure supply pipe 53 and supplies it to the high-pressure supply pipe 58. The high-pressure pump 57 has an electromagnetic valve 57a connected to its intake port that opens and closes when pressurizing the fuel, a check valve 57b connected to its discharge port that regulates the backflow of fuel and maintains the fuel pressure in the high-pressure supply pipe 58, and a plunger 57c that operates (moves up and down in FIG. 1) by the rotation of the engine 12 (rotation of the intake camshaft). When the electromagnetic valve 57a is open during operation of the engine 12, the high-pressure pump 57 sucks in fuel from the low-pressure supply pipe 53, and when the electromagnetic valve 57a is closed, the fuel compressed by the plunger 57c is intermittently sent to the high-pressure supply pipe 58 through the check valve 57b, thereby pressurizing the fuel to be supplied to the high-pressure supply pipe 58. When the high-pressure pump 57 is driven, the fuel pressure in the low-pressure supply pipe 53 and the fuel pressure in the high-pressure supply pipe 58 pulsates according to the rotation of the engine 12 (the rotation of the intake camshaft). The high-pressure supply pipe 58 is connected to the in-cylinder injection valve 26.

The electronic control unit 70 includes a microcomputer having a CPU 71, a ROM 72, a RAM 73, a flash memory 74, and input/output ports. Signals from various sensors are input to the electronic control unit 70 through the input ports. Examples of signals input to the electronic control unit 70 include the crank angle θcr from the crank position sensor 14a that detects the rotational position of the crankshaft 14 of the engine 12, the cooling water temperature Tw from the water temperature sensor 40 that detects the temperature of the cooling water of the engine 12, the atmospheric pressure Pa from the atmospheric pressure sensor 41 that detects the atmospheric pressure Pa, and the oil temperature Toil from the oil temperature sensor 42 that detects the temperature of the lubricating oil of the engine 12. Cam angles θci and θco from the cam position sensor 44 that detects the rotational position of the intake camshaft that opens and closes the intake valve 28 and the rotational position of the exhaust camshaft that opens and closes the exhaust valve 31 can also be mentioned. Other examples include the throttle opening TH from a throttle position sensor 24a that detects the position of the throttle valve 24, the intake air amount Qa from an air flow meter 23a attached upstream of the throttle valve 24 in the intake pipe 23, and the intake air temperature Ta from a temperature sensor 23t attached upstream of the throttle valve 24 in the intake pipe 23. Other examples include an air-fuel ratio AF from an air-fuel ratio sensor 35 attached upstream of the purification device 34 in the exhaust pipe 33, and an oxygen signal O2 from an oxygen sensor 36 attached downstream of the purification device 34 in the exhaust pipe 33. Other examples include the fuel temperature Tftnk from a fuel temperature sensor 51t attached to the fuel tank 51, the feed pump 52 rotation speed Nlp from a rotation speed sensor 52a attached to the feed pump 52, the low-pressure fuel pressure (the pressure of the fuel supplied to the port injection valve 25) Pflo from a fuel pressure sensor 53p attached to the low-pressure supply pipe 53 near the port injection valve 25 (e.g., the low-pressure delivery pipe), and the high-pressure fuel pressure (the pressure of the fuel supplied to the in-cylinder injection valve 26) Pfhi from a fuel pressure sensor 58p attached to the high-pressure supply pipe 58 near the in-cylinder injection valve 26 (e.g., the high-pressure delivery pipe).

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 throttle valve 24 of the engine 12, a control signal to the port injection valve 25, a control signal to the in-cylinder injection valve 26, and a control signal to the spark plug 30. Other examples include a control signal to the feed pump 52 of the fuel supply device 50, and a control signal to the electromagnetic valve 57a of the high-pressure pump 57.

The electronic control unit 70 calculates the rotation speed Ne of the engine 12 based on the crank angle θcr from the crank position sensor 14a. The electronic control unit 70 also calculates 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) based on the intake air amount Qa from the air flow meter 23a and the rotation speed Ne of the engine 12. Furthermore, the electronic control unit 70 estimates the temperature Tc of the catalyst 34a of the purification device 34 based on the cooling water temperature Tw from the water temperature sensor 40, the rotation speed Ne of the engine 12, and the load factor KL. In addition, the electronic control unit 70 estimates the fuel temperature Tfhp in the high-pressure pump 57 based on the cooling water temperature Tw, the oil temperature Toil from the oil temperature sensor 42, and the intake air temperature Ta from the temperature sensor 23t.

In the engine device 10 of the embodiment configured in this manner, the CPU 71 of the electronic control unit 70 controls the intake air volume, fuel injection, and ignition of the engine 12 as part of the operation control of the engine 12, and also controls the feed pump 52 and high-pressure pump 57 (electromagnetic valve 57a) of the fuel supply device 50.

For example, the intake air amount control of the engine 12 sets the required air amount Qa* based on the accelerator opening and the engine 12 revolution speed Ne, sets the target opening TH* of the throttle valve 24 so that the intake air amount Qa becomes the required air amount Qa*, and controls the throttle valve 24 using the target opening TH*. For fuel injection control of the engine 12, the required injection amount Qf* is basically set based on the required air amount Qa* and the target air-fuel ratio AF*, the fuel injection period Tf is set based on the required injection amount Qf* and the high pressure fuel pressure Pfhi, the injection start time θst is set so that fuel injection ends by the retard guard θendlim as the injection end limit, and the in-cylinder injection valve 26 is controlled to inject fuel for the fuel injection period Tf from the injection start time θst. Ignition control of the engine 12 sets the target ignition timing Ti* of the spark plug 30 based on the engine 12 rotation speed Ne and required air volume Qa*, and controls the spark plug 30 using the set target ignition timing Ti*.

Next, the operation of the engine device 10 of the embodiment thus configured will be described, in particular the operation when fuel is injected from the in-cylinder injection valve 26 to operate the engine 12 at high output (high rotation and high torque). FIG. 2 is a flow chart showing an example of in-cylinder injection control executed by the electronic control unit 70. This process is executed at a predetermined timing before the start of the intake stroke for each cylinder.

In the in-cylinder injection control, the electronic control unit 70 first sets the required injection amount Qf* based on the required air amount Qa* and the target air-fuel ratio AF* (step S100), and then sets the fuel injection period Tf based on the required injection amount Qf*, the high pressure fuel pressure Pfhi, and the rotation speed Ne of the engine 12 (step S110). The fuel injection period Tf can be calculated by multiplying the time required for the in-cylinder injection valve 26 to inject the required injection amount Qf* at the high pressure fuel pressure Pfhi by the crank angle at which the crankshaft 14 rotates per unit time. Therefore, the fuel injection period Tf is the change (angle) in the crank angle at which the in-cylinder injection valve 26 is opened. In addition, when changing gears while the engine 12 is operating at high power (high revolutions and high torque), the fuel is retarded and increased so that the catalyst does not overheat, so the required injection amount Qf* is calculated based on the required air amount Qa* and the target air-fuel ratio AF* and the retarded amount is added to that calculated.

Next, the injection start timing θst is set to the optimal start timing θopt (step S120), and the time that is the fuel injection period Tf from the injection start timing θst is set as the injection end timing θend (step S130). The optimal start timing θopt is the optimal time for starting fuel injection from the in-cylinder injection valve 26, and is determined in advance through experiments, etc. Now, when the optimal timing θopt is BTDCXXX (Before TDC XXX degrees) and the fuel injection period Tf is 90 degrees, the injection end timing θend can be calculated as BTDC (XXX-90) (Before TDC (XXX-90) degrees).

Next, it is determined whether the injection end timing θend is retarded from the retard guard θendlim (step S140). The retard guard θendlim is determined as the injection end limit, and can be, for example, bottom dead center (BTDC180). As described above, when the engine 12 is operated at high power (high rotation and high torque), the amount of fuel retarded is increased during gear changes, so that the injection end timing θend may be retarded from the retard guard θendlim. If it is determined that the injection end timing θend is not retarded from the retard guard θendlim, fuel is injected from the in-cylinder injection valve 26 using the injection start timing θst set with the optimal start timing θopt and the injection end timing θend set in step S130 (step S220), and this control is terminated.

When it is determined in step S140 that the injection end timing θend is retarded from the retard guard θendlim, the retard guard θendlim is set as the injection end timing θend (step S150), and the timing preceding the injection end timing θend by the fuel injection period Tf is set as the injection start timing θst (step S160). Then, the advance guard θstlim is set based on the engine 12 rotation speed Ne, load factor KL, and atmospheric pressure Pa (step S170). The advance guard θstlim must be set so that the injection start timing θst does not fall within the scavenge region. The scavenge region is a suitable region with a large amount of overlap based on the opening and closing timing of the intake valve 28 and exhaust valve 31 of the engine 12, so it is better to determine it based on a two-dimensional map of the engine 12 rotation speed Ne and load factor KL that determine the valve opening and closing timing. In addition, since the lower the atmospheric pressure Pa, the more likely it is that fuel will be blown through due to scavenging, it is preferable to set the advance guard θstlim so that it tends to be more retarded as the atmospheric pressure Pa becomes lower. As a result of these factors, it is preferable to determine the advance guard θstlim based on the engine 12 rotation speed Ne, load factor KL, and atmospheric pressure Pa. In the embodiment, the relationship between the engine 12 rotation speed Ne, load factor KL, atmospheric pressure Pa, and the advance guard θstlim is determined in advance by experiment or the like and stored as an advance guard setting map, and when the engine 12 rotation speed Ne, load factor KL, and atmospheric pressure Pa are given, the advance guard θstlim obtained by applying these to the advance guard setting map is derived as the advance guard θstlim to be set.

When the advance guard θstlim is set, it is determined whether the injection start timing θst is more advanced than the advance guard θstlim (step S180). As described above, when the engine 12 is operated at high power (high rotation and high torque) and shifting gears, the amount of fuel retarded is increased, so the injection start timing θst may be more advanced than the advance guard θstlim. If it is determined that the injection start timing θst is not more advanced than the advance guard θstlim, fuel is injected from the in-cylinder injection valve 26 using the injection start timing θst set in step S160 and the injection end timing θend set as the retard guard θendlim in step S150 (step S220), and this control is terminated.

When it is determined in step S180 that the injection start timing θst is more advanced than the advance guard θstlim, the advance guard θstlim is set as the injection start timing θst (step S190), and the fuel shortage injection amount Psh that is insufficient for in-cylinder injection based on the fuel shortage injection period obtained by subtracting the angle from the injection start timing θst to the injection end timing θend from the fuel injection period Tf is calculated (step S200). The fuel shortage injection amount Psh can be calculated by multiplying the fuel shortage injection period divided by the crank angle at which the crankshaft 14 rotates per unit time by the amount of fuel injected per unit time by the in-cylinder injection valve 26 at the high fuel pressure Pfhi. Then, the fuel shortage injection amount Psh is injected from the port injection valve 25 (step S210), and fuel is injected from the in-cylinder injection valve 26 using the injection start timing θst set with the advance guard θstlim in step S190 and the injection end timing θend set with the retard guard θendlim in step S150 (step S220), and this control ends. The fuel shortage injection amount Psh is injected from the port injection valve 25 by multiplying the time required for the port injection valve 25 to inject the fuel shortage injection amount Psh at the low fuel pressure Pflo by the crank angle at which the crankshaft 14 rotates per unit time to calculate the fuel injection period Tp, and opening the port injection valve 25 for the fuel injection period Tp at an appropriate time during the intake stroke.

Figure 3 is an explanatory diagram showing example cases in which the injection start time θst and the injection end time θend are set by in-cylinder injection control. In case (a), the injection start time θst is set to the optimal start time θopt, and the injection end time θend is set to the time that is the fuel injection period Tf from the injection start time θst, and the injection end time θend is not retarded beyond the retard guard θendlim. In this case, fuel is injected from the in-cylinder injection valve 26 using the injection start time θst set to the optimal start time θopt, and the injection end time θend set as the time that is the fuel injection period Tf from the injection start time θst.

In case (b), the injection start time θst is set to the optimal start time θopt, and the injection end time θend is set to the time that is the fuel injection period Tf from the injection start time θst. The injection end time θend is retarded from the retard guard θendlim. Therefore, when the retard guard θendlim is set as the injection end time θend and the injection start time θst is set to the time that is the fuel injection period Tf back from the injection end time θend, the injection start time θst is not advanced from the advance guard θstlim. In this case, fuel is injected from the in-cylinder injection valve 26 using the injection end time θend for which the retard guard θendlim is set and the injection start time θst that is set to the time that is the fuel injection period Tf back from the injection end time θend.

In case (c), similarly to case (b), the injection start time θst is set to the optimal start time θopt, and the time that is the fuel injection period Tf from the injection start time θst is set to the injection end time θend, and the injection end time θend is retarded from the retard guard θendlim. Therefore, when the retard guard θendlim is set as the injection end time θend, and the time that is the fuel injection period Tf back from the injection end time θend is set to the injection start time θst, the injection start time θst is advanced from the advance guard θstlim. In this case, fuel is injected from the in-cylinder injection valve 26 using the injection end time θend set to the retard guard θendlim and the injection start time θst set to the advance guard θstlim, and the shortage fuel injection amount Psh is injected from the port injection valve 25.

In the engine device 10 of the embodiment described above, when fuel is injected from the in-cylinder injection valve 26 and the engine 12 is operated at high output (high rotation and high torque), the injection start time θst is set to the optimal start time θopt and the time that is the fuel injection period Tf from the injection start time θst is set to the injection end time θend. When the injection end time θend is retarded more than the retard guard θendlim, the retard guard θendlim is set as the injection end time θend, and the time that is the fuel injection period Tf back from the injection end time θend is set to the injection start time θst. At this time, when the injection start timing θst is more advanced than the advance guard θstlim, the retard guard θendlim is set as the injection end timing θend, and the advance guard θstlim is used as the injection start timing θst to inject fuel from the in-cylinder injection valve 26, and fuel is injected from the port injection valve 25 to compensate for the insufficient fuel injection amount Psh, which is insufficient with the amount of fuel injected from the in-cylinder injection valve 26. This allows for more appropriate fuel injection even when the engine 12 is operated in a high-power (high-speed, high-torque) range by injecting fuel from the in-cylinder injection valve 26.

The following describes the relationship between the main elements of the embodiment and the main elements of the invention described in the section on means for solving the problem. In the embodiment, the port injection valve 25 corresponds to the "port injection valve", the in-cylinder injection valve 26 corresponds to the "in-cylinder injection valve", the engine 12 corresponds to the "engine", and the electronic control unit 70 corresponds to the "control device".

The correspondence between the main elements of the Examples and the main elements of the invention described in the Means for Solving the Problem column does not limit the elements of the invention described in the Means for Solving the Problem column, since the Examples are examples for specifically explaining the form for implementing the invention described in the Means for Solving the Problem column. In other words, the interpretation of the invention described in the Means for Solving 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 Means for Solving the Problem column.

The above describes the form for carrying out the present invention using examples, but 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 invention.

The present invention can be used in the engine equipment manufacturing industry, etc.

10 engine device, 12 engine, 14 crankshaft, 14a crank position sensor, 15 crank position sensor, 22 air cleaner, 23 intake pipe, 23a air flow meter, 23t temperature sensor, 24 throttle valve, 24a throttle position sensor, 25 port injection valve, 26 in-cylinder injection valve, 28 intake valve, 29 combustion chamber, 30 spark plug, 31 exhaust valve, 32 piston, 33 exhaust pipe, 34 purification device, 34a catalyst, 35 air-fuel ratio sensor, 36 oxygen sensor, 40 water temperature sensor, 41 atmospheric pressure sensor, 42 oil temperature sensor, 44 cam position sensor, 50 fuel supply device, 51 fuel tank, 51t fuel temperature sensor, 52 feed pump, 52a rotation speed sensor, 53 low pressure supply pipe, 53p fuel pressure sensor, 54 check valve, 55 Relief flow passage, 56 relief valve, 57 high-pressure pump, 57a solenoid valve, 57b check valve, 57c plunger, 58 high-pressure supply pipe, 58p fuel pressure sensor, 70 electronic control unit, 71 CPU, 72 ROM, 73 RAM, 74 flash memory.

Claims (1)

an engine having a port injection valve that injects fuel into an intake port and an in-cylinder injection valve that injects fuel into a cylinder;
A control device for controlling the engine;
An engine device comprising:
when the engine is operated in a high rotation and high torque region by injecting fuel from the in-cylinder injection valve and the injection start timing determined by guarding the injection end timing with a retard guard defined as an injection retard limit is on the advanced side of an advance guard based on engine speed, load factor, and atmospheric pressure, the control device injects fuel from the port injection valve in an amount of fuel injection corresponding to a period of the fuel injection period that is longer than the period from the advance guard to the retard guard.
An engine device characterized by:

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