JP5169708B2 - Engine fuel control device - Google Patents

Description

  The present invention relates to a fuel control device for an engine including a blow-by gas processing device, and more particularly to an engine suitable for an engine including a blow-by gas processing device that ventilates blow-by gas both when the turbocharger is not operating and when the turbocharger is operating. The present invention relates to a fuel control device.

  Conventionally, an engine blow-by gas processing apparatus for ventilating blow-by gas both when the turbocharger is not operating and when operating is proposed (see Patent Document 1).

This includes a supercharger provided upstream of the throttle valve in the intake passage, a first blowby gas passage connecting the upstream position of the supercharger in the intake passage to the inside of the crankcase, and a throttle in the intake passage. A second blow-by gas passage connecting the position downstream of the valve to the crankcase, and a blow-by gas provided in the second blow-by gas passage and opened by intake negative pressure, from the crankcase side to the downstream position side of the intake passage And a flow rate control valve that allows the movement of. Then, when supercharging is performed by the supercharger, a predetermined amount of fresh air is allowed to move from the downstream position side of the intake passage to the crankcase side through the closed flow control valve. A notch is provided between the bodies.
JP 2004-60475 A

  By the way, when the blow-by gas processing device of the above-mentioned conventional example is applied to an engine equipped with a fuel control device that sets a fuel injection amount based on an intake air amount measured by an air flow meter, the turbocharger starts and stops transiently. Since the direction of the air flow flowing through the blow-by gas processing device sometimes changes, the amount of air detected by the air flow meter and the amount of air introduced into the combustion chamber are temporarily different. For this reason, it is expected that the fuel injection will be temporarily rich or lean with respect to the optimum fuel injection amount, the fuel consumption will deteriorate due to the increase in unburned HC, and the drivability will be reduced due to insufficient torque. .

  Therefore, the present invention has been made in view of the above-described problems, and is an engine fuel control equipped with a blow-by gas processing device that is suitable for optimally maintaining the fuel injection amount even when the turbocharger starts and stops transiently. An object is to provide an apparatus.

The present invention comprises a supercharger upstream of the throttle valve of the intake passage, and connects the upstream position of the supercharger of the intake passage to the inside of the crankcase via the first blow-by gas passage, A fuel control device for an engine comprising a blow-by gas processing device for connecting a position downstream of the throttle valve of the intake passage to a crankcase via a second blow-by gas passage provided with a flow control valve, wherein the supercharger of the supercharger e Bei control means temporarily increases or decreases adjusting the fuel injection amount during the operation transition between a state and a non-supercharged state, the increase or decrease adjustment of the temporary fuel injection quantity, the supercharger boost condition and the non Control is performed based on the recirculation amount of blow-by gas in which the flow direction is reversed with respect to the blow-by gas passage in the supercharged state.

Therefore, the present invention is an engine fuel control device including a blow-by gas processing device that enables recirculation of blow-by gas even during supercharging, and operates between a supercharged state and a non-supercharged state of the supercharger. Since the control means for temporarily adjusting the fuel injection amount at the time of transition is provided, the fuel injection amount can be optimally maintained even when the turbocharger starts and stops transiently. For this reason, it is suppressed that the fuel injection becomes temporarily rich or lean with respect to the optimal fuel injection amount, and the increase in unburned HC deteriorates the fuel consumption, and the deficiency in torque causes a decrease in drivability. Can be prevented.
Moreover, the temporary increase / decrease adjustment of the fuel injection amount is controlled based on the recirculation amount of the blow-by gas in which the flow direction is reversed with respect to the blow-by gas passage between the supercharged state and the non-supercharged state of the supercharger. Therefore, it is possible to cope with an increase or decrease in the amount of air introduced into the combustion chamber.

  DESCRIPTION OF EMBODIMENTS Hereinafter, an embodiment of an engine blow-by gas processing apparatus of the present invention will be described with reference to FIGS. FIG. 1 is a system configuration diagram showing a first embodiment of an engine fuel control apparatus equipped with a blow-by gas processing apparatus to which the present invention is applied, FIG. 2 is a cross-sectional view of a flow control valve used, and FIG. FIG. 4 is a flowchart of the fuel injection amount correction control, and FIGS. 5 and 6 are explanatory views for explaining the operating state at the time of transition from when the supercharger is operated to when not operating.

  In FIG. 1, an intake passage 11 of an automobile engine E has an air cleaner 12, a compressor 13 constituting a turbocharger or a supercharger, and an intercooler from the upstream side to the downstream side of the intake air flow. 14, a throttle valve 15, a collector (not shown) and an intake manifold 16 are arranged. A flow rate control valve 23 whose opening degree is controlled by the control unit 10 of the engine E is disposed in a second blow-by gas passage 22 that connects the intake manifold 16 and the inside of a crankcase (not shown) of the engine E. The first blow-by gas passage 21 connects the upstream of the compressor 13 and the inside of a crankcase (not shown) of the engine E. The first blow-by gas passage 21 and the second blow-by gas passage 22 communicate with each other via the inside of the crankcase of the engine E in which blow-by gas accumulates. Although not shown, the turbocharger compressor 13 is provided with a bypass passage and a bypass valve for bypassing the turbocharger and allowing intake air to pass through when not supercharging. Note that the first blow-by gas passage 21, the crankcase inner space, and the second blow-by gas passage 22 are also collectively referred to as a blow-by gas passage (no symbol).

  As shown in FIG. 2, the flow control valve 23 drives the valve rod 30 in the sliding direction, and a valve portion 30 composed of a valve seat 31 and a valve rod 32 that slides on and fits the valve seat 31. The drive part comprised by the step motor 35 to perform is provided.

  The valve seat 31 of the valve portion 30 is formed with a hole 31A that fits into the valve stem 32, and a hole 31A that is shallow on the one end side in the axial direction (lower side in the drawing) and deep on the other end side in the axial direction. Provided with a valve opening 31B formed of a plurality of grooves extending in the axial direction. Further, the valve rod 32 of the valve portion 30 is fitted into the hole 31A of the valve seat 31 and is moved to the tip end side in the axial direction, so that the valve opening area is reduced, the valve is closed, and is retracted in the axial direction. The valve opening area is increased by turning (moving upward in the figure).

  The drive unit includes a rotor 37 rotatably supported by a case 36 and screw-engaged with the valve stem 32, and a stator 38 disposed around the rotor 37 with a gap therebetween. The step motor 35 is configured to control the rotation angle position of the rotor 37 according to the number. Then, the rotational angle position of the rotor 37 is adjusted according to the number of command steps from the control unit 10, and when the number of command steps is zero, the valve rod 32 screw-engaged with the rotor 37 is set to the most advanced position. The valve opening area is minimized (valve closed) by sliding and engaging with the lower end position of the valve seat 31. Further, the valve rod 32 is retracted according to the number of command steps to increase the relative clearance with the valve seat 31 so that the valve opening can be adjusted. Thus, by using the step motor 35 having a large driving force, the flow rate control valve 23 can be operated even in a state where the supercharging pressure is applied, and the flow rate can be controlled. Further, it is possible to prevent the supercharging pressure from being directly applied to the engine E.

  The control unit 10 includes a manifold pressure signal from a manifold pressure sensor 25 that detects the pressure of the intake manifold 16 (collector), an atmospheric pressure signal from an atmospheric pressure sensor 24 that detects the pressure in the intake passage 11 downstream of the air cleaner 12, and An intake air amount signal from an air flow meter 26, an accelerator opening signal from an accelerator opening sensor 27 that detects the amount of depression of an accelerator pedal, an engine speed signal from a position sensor 28 that detects a crank angle (not shown) of the engine E, Etc. are input. Based on these input signals, in addition to controlling the opening degree of the flow rate control valve 23, the opening degree of the throttle valve 15, the fuel injection amount of the fuel injection valve 29, the ignition timing, the operation of the supercharger, etc. are controlled. To do.

  The blow-by gas processing device for the engine E having the above-described configuration is an idling operation state where the accelerator opening is near zero and the engine speed is low, and the low-speed engine E where the accelerator pedal is not depressed and the turbocharger is inoperative. When the engine is negative, fresh air is sucked into the engine E through the air cleaner 12, the compressor 13 (bypass valve not shown), the intercooler 14, the throttle valve 15, and the intake manifold 16 due to the intake negative pressure generated by the engine E. At this time, a portion of the fresh air that has passed through the air cleaner 12 due to the intake negative pressure acting on the intake manifold 16 is from the upstream of the compressor 13 to the first blow-by gas passage 21, the crankcase, the second blow-by gas passage 22, and the flow control valve 23. Then, it is sucked into the engine E through the intake manifold 16. The blow-by gas in the crankcase is sucked into the engine E together with the fresh air, so that the crankcase is ventilated and deterioration of the lubricating oil of the engine E due to NOx or the like contained in the blow-by gas is minimized.

  As shown in FIG. 3, the reflux amount at that time is minimized to, for example, 12 [L / min] in the idling operation state, and the engine speed is in a low / medium speed rotation region (for example, ˜5000 [rpm]). ) Is set to a maximum flow rate of 60 [L / min], for example, and is set to be halved to, for example, 30 [L / min] in a high-speed rotation region (for example, 5000 [rpm]). In this way, oil consumption can be reduced by controlling the amount of reflux to be small in the high-speed rotation region. Then, the valve opening degree of the flow control valve 23 is adjusted according to the pressure difference between the intake manifold 16 and the upstream intake passage 11 so as to achieve the target ventilation amount.

  Further, when the engine E where the accelerator pedal is depressed greatly and the turbocharger operates is high, a supercharging pressure is generated in the intake manifold 16 provided in the intake passage 11 on the downstream side of the compressor 13, so that the internal pressure of the intake manifold 16 is increased. Becomes higher than the internal pressure of the crankcase. Therefore, high-pressure fresh air in the intake manifold 16 passes through the second blow-by gas passage 22 and the flow rate control valve 23, and returns to the upstream side of the compressor 13 through the crankcase and the first blow-by gas passage 21. At that time, the blow-by gas in the crankcase is returned to the upstream intake passage 11 together with the fresh air and is sucked into the engine E, whereby the crankcase is ventilated and the engine is caused by NOx or the like contained in the blow-by gas. Degradation of E's lubricating oil is minimized.

  As shown in FIG. 3, the recirculation amount at that time is, for example, 60 [L / min] and a maximum flow rate when the engine speed is low and medium speed (for example, up to 5000 [rpm]). In the rotation region (for example, 5000 [rpm] to), it is set to be halved to 30 [L / min], for example. Then, the valve opening degree of the flow control valve 23 is adjusted according to the pressure difference between the intake manifold 16 and the upstream intake passage 11 so as to achieve the target ventilation amount.

  The routine shown in FIG. 4 is a flowchart for correcting and controlling the fuel injection amount at the time of transition from the supercharged state to the non-supercharged state or from the non-supercharged state to the supercharged state, and is executed by the control unit 10. This will be described below.

  First, in step 1, the accelerator opening signal from the accelerator opening sensor 27, the pressure in the upstream intake passage 11 and the pressure in the intake manifold 16 are the pressure signals from the atmospheric pressure sensor 24 and the manifold pressure sensor 25, the supercharger The operating state, the intake air amount by the air flow meter 26, and the like are read, and the process proceeds to step S2. In step S2, it is determined whether or not the opening difference with respect to the previous value of the current accelerator opening exceeds a set value. If so, the process proceeds to step 3 where the supercharger operating state is in the supercharging state. Is determined from the non-supercharged state or from the non-supercharged state to the supercharged state. If the supercharged state is changed, the process proceeds to the next step 4 to determine the fuel injection amount. Correction control is started.

  However, either the determination of whether or not the opening difference with respect to the previous value of the current accelerator opening in step 2 exceeds the set value or the change determination of the operating state of the supercharger in step 3 is denied. In this case, the fuel injection amount correction control is not started, and the current processing step is ended.

  In step 4 in which correction control of the fuel injection amount is started, the flow rate at that time is determined based on the pressure difference from the atmospheric pressure sensor 24 and the manifold pressure sensor 25 based on the pressure difference between them and the opening degree of the flow control valve 23. The recirculation amount of the blow-by gas passing through the control valve 23 is calculated, and the process proceeds to step 5.

  In step 5, it is determined whether or not the change in the accelerator opening in step 2 is an increase. The increase is a case where the operation of the supercharger is started, and the process proceeds to step 6, where it is a decrease. The case is when the operation of the supercharger is stopped, and the process proceeds to step 7.

  In step 6 which proceeds when the accelerator opening is increased and the supercharger is operated, the fuel injection amount (decrease) is corrected and the process proceeds to step 8. The fuel injection amount (decrease) correction is calculated by, for example, (intake air amount by air flow meter 26−recirculation amount by flow control valve 23) / intake air amount by air flow meter. This is because the entire amount of intake air by the air flow meter 26 is supplied to the collector (intake manifold 16) by the supercharger, but the increase (recirculation amount) cannot catch up (with a time delay), so part of it. This is caused by being diverted from the collector (intake manifold 16) and flowing to the blow-by gas passage. For this reason, the amount of air obtained by subtracting the recirculation amount flowing to the flow control valve 23 from the flow rate temporarily measured by the air flow meter 26 is led to the combustion chamber, and the amount (ratio (the amount of intake air by the air flow meter 26). -If the fuel injection amount is not reduced by the amount of recirculation by the flow control valve 23) / the amount of intake air by the air flow meter 26), it means that the air-fuel ratio in the combustion chamber becomes rich (overconcentration).

  Further, in step 7 which proceeds when the accelerator opening is decreased and the supercharger is inactivated, the fuel injection amount (increase) is corrected and the process proceeds to step 8. The fuel injection amount (increase) correction is calculated by, for example, (intake air amount by air flow meter 26 + recirculation amount by flow control valve 23) / intake air amount by air flow meter 26. This is because the air amount obtained by adding the recirculation amount of blow-by gas to the total amount of intake air amount by the air flow meter 26 is supplied to the collector (intake manifold 16) by the supercharger. Although it is throttled by stopping the feeder, the flow rate immediately after subtracting the recirculation amount to the blow-by gas passage is accompanied by a time delay. In addition, due to the decrease in the throttle valve opening and the suspension of the supercharger, a recirculation amount forcibly flowing back into the blow-by gas passage is generated and flows into the collector (intake manifold 16). Therefore, the air that temporarily flows into the collector (intake manifold 16) is obtained by adding the air amount before and after the intake air amount by the air flow meter 26 and the recirculation amount that recirculates through the blow-by gas passage. That is, the amount of air obtained by adding the recirculation amount flowing to the flow control valve 23 to the flow rate temporarily measured by the air flow meter 26 is led to the combustion chamber, and the amount (ratio (the amount of intake air by the air flow meter 26 + If the fuel injection amount is not increased by the recirculation amount by the flow rate control valve 23 / the intake air amount by the air flow meter 26), it means that the air-fuel ratio in the combustion chamber becomes lean.

  In step 8, it is determined whether or not the pressure in the collector (intake manifold 16) is stabilized at the target pressure (supercharging pressure or negative pressure). To Step 6 or Step 4 to Step 7 are repeatedly executed. The pressure in the collector (intake manifold 16) changes with time, and the recirculation amount passing through the flow control valve 23 in step 4 also changes accordingly. If it is determined in step 8 that the pressure in the collector (intake manifold 16) has stabilized at the target pressure (supercharging pressure or negative pressure), the process proceeds to step 9 to perform fuel correction control during transition. End a series of processing.

  FIG. 5 is an explanatory diagram for explaining the intake air flow state when the accelerator opening is decreased and the supercharger is deactivated, and FIG. 6 is the case where the accelerator opening is increased and the supercharger is operated. It is explanatory drawing explaining the intake airflow state in a case.

  First, the intake air flow state when the accelerator opening is decreased and the supercharger is changed from the operating state to the non-operating state will be described based on the explanatory diagram of FIG.

  FIG. 5 (A) shows a state at the time of supercharging, where the intake air amount F1 is measured by the air flow meter 26 and merged with the recirculation amount F2 returning from the first blow-by gas passage 21, and a supercharger constituted by a supercharger. 13 is sent downstream and introduced into the collector 16A (intake manifold 16) via the throttle valve 15 (introduction amount F1 + F2). The collector pressure at this time is positive due to the supply by the supercharger 13. Part of the introduced air (F 2) is diverted to the blow-by gas passage 22 and supplied into the crankcase CC of the engine E via the flow control valve 23. Then, the remaining air amount (F1) is introduced into the combustion chamber A.

  When the accelerator pedal is suddenly returned from this state, the throttle opening is also rapidly reduced, and the supercharging operation of the supercharger 13 is stopped. Due to the decrease in the throttle valve opening and the suspension of the supercharger 13, the inflow to the collector 16A through the intake passage 11 is throttled, but the inflow to the collector 16A is continued due to its inertia, and immediately the first blow-by gas The flow rate change to the flow rate (F1-F2) obtained by subtracting the reflux amount F2 to the passage 21 is accompanied by a time delay.

  On the other hand, by reducing the throttle valve opening and stopping the supercharger 13, a recirculation amount F2 forcibly flowing back to the first blow-by gas passage 21 is generated, and to the collector 16A (intake manifold 16) via the blow-by gas passage. The amount of reflux F2 that flows in increases rapidly. The recirculation amount F2 is determined by the differential pressure between the manifold negative pressure and the atmospheric pressure and the opening degree of the flow control valve 23, and is increased in accordance with a decrease in the manifold pressure to a negative pressure.

  Therefore, as shown in FIG. 5B, the air that temporarily flows into the collector 16A is the amount of intake air introduced through the intake passage 11 (around F1) and the amount of recirculation that recirculates through the blow-by gas passage. The amount of air (F1 + F2) is added to (F2), and this is introduced into the combustion chamber of the engine E.

  That is, an air flow (F1 + F2) obtained by adding the recirculation amount F2 flowing to the flow rate control valve 23 to the flow rate F1 temporarily measured by the air flow meter 26 is guided to the combustion chamber A, and the amount (ratio (air flow meter 26 The fuel injection amount is increased by the intake air amount F1 due to the above (the recirculation amount F2 due to the flow rate control valve 23) / the intake air amount F1 due to the air flow meter 26 (step 7), and the air-fuel ratio in the combustion chamber A becomes lean (diluted). Can be prevented.

  The change during the transition is that the amount of air flowing through the intake passage 11 converges to (F1-F2) when the collector pressure (intake manifold pressure) is stabilized at a predetermined value, and the amount of air flowing through the blow-by gas passage. Is converged to (F2), it becomes possible to shift to the fuel injection amount at the time of non-supercharging, and a series of correction control is completed.

  Next, the intake air flow state when the accelerator opening is increased and the supercharger 13 is changed from the non-operating state to the operating state will be described based on the explanatory diagram of FIG.

  FIG. 6A shows a non-supercharging state, the intake air amount F1 is measured by the air flow meter 26, the recirculation amount F2 to the first blow-by gas passage 21 is divided, and the supercharger configured by a supercharger. It is sent downstream via the bypass valve B that bypasses the machine 13, and is introduced into the collector 16A (intake manifold 16) via the throttle valve 15 (introduction amount F1-F2). The collector pressure at this time is negative due to the non-operation of the supercharger 13. The introduced air (F1-F2) merges with the return air (F2) from the second blowby gas passage 22 through the crankcase CC of the engine E and the flow rate control valve 23 to obtain an air amount (F1). It is introduced into the combustion chamber A.

  When the accelerator pedal is stepped on suddenly from this state, the throttle opening increases rapidly, and the supercharging operation of the supercharger 13 is started. The increase in the throttle valve opening and the start of the operation of the supercharger 13 promote the inflow to the collector 16A through the intake passage 11, but the increase in the inflow to the collector 16A is delayed due to the inertia of the air. The flow rate change to the flow rate (F1 + F2) obtained by adding the recirculation amount F2 to the second blow-by gas passage 22 is accompanied by a time delay.

  On the other hand, by increasing the throttle valve opening and starting the operation of the supercharger 13, a recirculation amount F2 that flows from the collector 16A (intake manifold 16) to the second blow-by gas passage 22 is generated, and the collector pressure (intake manifold pressure) is generated. As the flow rate increases, the recirculation amount F2 flowing into the second blow-by gas passage 22 increases rapidly. The recirculation amount F2 is determined by the differential pressure between the manifold pressure and the atmospheric pressure and the opening degree of the flow control valve 23, and is increased according to the increase of the manifold pressure to the positive pressure.

  For this reason, as shown in FIG. 6B, the amount of recirculation (F2) recirculated from the intake air amount (corresponding to F1) introduced through the intake passage 11 to the second blow-by gas passage 22 is temporarily changed. The subtracted air amount (F1-F2) remains in the collector 16A and is introduced into the combustion chamber A of the engine E.

  That is, the air flow (F1-F2) obtained by subtracting the recirculation amount F2 flowing to the flow control valve 23 from the flow rate F1 that is temporarily measured by the air flow meter 26 is guided to the combustion chamber A, and the amount (ratio (air flow meter 26, the fuel injection amount is reduced by the intake air amount F1-recirculation amount F2 by the flow control valve 23) / intake air amount F1 by the air flow meter 26 (step 6), and the air-fuel ratio in the combustion chamber A is rich (excessive). (Concentration) can be prevented.

  The change during the transition is that the collector pressure (intake manifold pressure) is stabilized at a predetermined value, so that the amount of air flowing through the intake passage 11 converges to (F1 + F2), and the amount of air flowing through the blow-by gas passage is ( By converging with F2), it becomes possible to shift to the fuel injection amount at the time of supercharging, and a series of correction control ends.

  In the present embodiment, the following effects can be achieved.

  (A) The turbocharger 13 is provided at a position upstream of the throttle valve 15 in the intake passage 11, and the position upstream of the supercharger 13 in the intake passage 11 is connected to the crankcase CC via the first blow-by gas passage 21. Fuel of an engine E provided with a blow-by gas processing device that is connected to the inside and connects a position downstream of the throttle valve 15 of the intake passage 11 to the crankcase CC via a second blow-by gas passage 22 provided with a flow control valve 23 It is a control device, and includes a control means 10 that temporarily adjusts the fuel injection amount to increase or decrease when the operation of the supercharger 13 is shifted between a supercharged state and a non-supercharged state. For this reason, the fuel injection amount can be optimally maintained even when the operation of the turbocharger 13 is started and stopped, and the fuel injection amount can be temporarily rich or lean with respect to the optimal fuel injection amount. It is possible to prevent the fuel efficiency from deteriorating due to the increase in the unburned HC and the drivability from being lowered due to insufficient torque.

  (A) Temporary increase / decrease adjustment of the fuel injection amount is controlled based on the recirculation amount of the blow-by gas in which the flow direction is reversed with respect to the blow-by gas passage between the supercharged state and the non-supercharged state of the supercharger 13. Therefore, it is possible to cope with an increase or decrease in the amount of air introduced into the combustion chamber A.

  (C) Temporarily adjusting the fuel injection amount to be increased / decreased when the supercharger 13 shifts from the non-supercharged state to the supercharged state, so the air-fuel ratio in the combustion chamber A becomes excessively rich. This can be suppressed, emission of unburned HC can be reduced, and fuel consumption can be improved.

  (D) The adjustment of increase / decrease in the fuel injection amount is temporarily corrected when the operation of the supercharger 13 is shifted from the supercharged state to the non-supercharged state, so that the air-fuel ratio in the combustion chamber A becomes lean. It is possible to suppress the output torque from being temporarily insufficient and the drivability from being deteriorated.

  (E) When the fuel injection amount is temporarily adjusted to increase or decrease, the pressure change in the intake manifold 16 downstream of the throttle valve 15 after the operation transition between the supercharged state and the non-supercharged state of the supercharger 13 converges. Since the process is terminated at the time, the control during the transition is not continued to the steady state.

  (F) A manifold pressure sensor 25 for detecting the pressure in the intake manifold 16 downstream of the throttle valve 15 in the intake passage 11 and an atmospheric pressure sensor 24 for detecting the pressure in the intake passage 11 upstream of the supercharger 13. The amount of recirculation of the blow-by gas is calculated by the pressure difference between both pressures detected by the manifold pressure sensor 25 and the atmospheric pressure sensor 24 and the valve opening degree of the flow control valve 23. The amount of blow-by gas recirculated can be determined, and the fuel injection amount can be accurately corrected.

BRIEF DESCRIPTION OF THE DRAWINGS The system block diagram which shows 1st Embodiment of the fuel control apparatus of an engine provided with the blowby gas processing apparatus which shows one Embodiment of this invention. Sectional drawing of the flow control valve used similarly. Map for reflux control. 7 is a flowchart of fuel injection amount correction control. Explanatory drawing explaining the operation state at the time of the transition at the time of the operation | movement of a supercharger-non-operation. Explanatory drawing explaining the operation state at the time of the transition at the time of the non-operation-operation of a supercharger.

Explanation of symbols

E Engine 10 Control unit 11 Intake passage 12 Air cleaner 13 Compressor (supercharger)
14 Intercooler 15 Throttle valve 16 Intake manifold (collector)
21 First blow-by gas passage 22 Second blow-by gas passage 23 Flow control valve 24 Atmospheric pressure sensor 25 Manifold pressure sensor 29 Fuel injection valve 35 Step motor

Claims (5)

A supercharger is provided at a position upstream of the throttle valve in the intake passage, the upstream position of the supercharger in the intake passage is connected to the inside of the crankcase through the first blow-by gas passage, and a flow control valve is provided. An engine fuel control device including a blow-by gas processing device that connects a position downstream of the throttle valve of the intake passage to a crankcase via a second blow-by gas passage provided;
E Bei control means temporarily increases or decreases adjusting the fuel injection amount during the operation transition between the boost condition and the non-supercharging condition of the supercharger,
The increase / decrease adjustment of the temporary fuel injection amount is controlled based on the recirculation amount of blow-by gas in which the flow direction is reversed with respect to the blow-by gas passage between a supercharged state and a non-supercharged state of the supercharger. An engine fuel control device. The engine fuel control apparatus according to claim 1, wherein the increase / decrease adjustment of the temporary fuel injection amount is corrected to decrease when the operation of the supercharger shifts from the non-supercharged state to the supercharged state . The engine fuel control apparatus according to claim 1 , wherein the temporary increase / decrease adjustment of the fuel injection amount is corrected to increase when the operation of the supercharger is shifted from the supercharged state to the non-supercharged state . The increase / decrease adjustment of the temporary fuel injection amount is terminated when the pressure change of the intake manifold downstream of the throttle valve converges after the operation transition between the supercharged state and the non-supercharged state of the turbocharger. fuel control system for an engine according to any one of claims 1 to 3, characterized in that that. A manifold pressure sensor for detecting the pressure in the intake manifold downstream of the throttle valve in the intake passage, and an atmospheric pressure sensor for detecting the pressure in the intake passage upstream of the supercharger,
5. The recirculation amount of the blow-by gas is calculated from a pressure difference between both pressures detected by a manifold pressure sensor and an atmospheric pressure sensor and a valve opening degree of the flow control valve. The engine fuel control device according to any one of the above.

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