JP2018132006A - Control device of on-vehicle internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control device of an on-vehicle internal combustion engine which can avoid that a gas which is high in a purge gas concentration is introduced into a combustion chamber, and thereby an air-fuel ratio becomes rich when an operation state is transited to a deceleration state from an acceleration state.SOLUTION: A control device 500 comprises a purge control part 501 and a supercharge control part 502. When supercharge is performed, the purge control part 501 performs a purge by selecting a first purge passage 381 as a purge path, when the supercharge is not performed, performs the purge by selecting a second purge passage 382 as the purge path, and on the other hand, when an operation state of an internal combustion engine 10 is transited to a deceleration state, stops the purge. Furthermore, when the operation state is transited to the deceleration state from an acceleration state that the supercharge is performed, the supercharge control part 502 performs supercharger rotation number suppression control for raising a deceleration speed of a rotation number of a compressor 220 of a supercharger 200 rather than the case that the purge gas concentration is lower than a normal concentration on condition that the purge gas concentration is not lower than the normal concentration.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a control device for an in-vehicle internal combustion engine that controls an in-vehicle internal combustion engine equipped with a supercharger.

  An in-vehicle internal combustion engine mounted on a vehicle is provided with an evaporated fuel processing system that processes evaporated fuel generated in a fuel tank. The evaporated fuel processing system includes a canister that collects evaporated fuel generated in a fuel tank and a purge passage that communicates the intake passage and the canister of the internal combustion engine, and the fuel collected in the canister is operated as purge gas together with air. The purge introduced into the intake passage of the internal combustion engine is performed. By performing such purging during engine operation, the fuel collected in the canister can be burned and processed in the combustion chamber of the internal combustion engine, and the collecting ability of the canister can be recovered.

  As an evaporative fuel processing system for an in-vehicle internal combustion engine equipped with a supercharger, Patent Document 1 discloses a first purge passage connected to the upstream side of the compressor in the intake passage and a downstream side of the throttle valve in the intake passage. And an evaporative fuel processing system including a second purge passage.

  In an internal combustion engine equipped with this evaporative fuel processing system, an electromagnetic valve provided in each purge passage is opened and closed to switch through which purge passage the purge is performed. Specifically, when the intake pressure downstream of the throttle valve is negative, purging is performed through the second purge passage, supercharging is performed, and the intake pressure downstream of the throttle valve is positive. Sometimes purging is performed through the first purge passage. And at the time of deceleration, both solenoid valves are closed and purge is stopped.

JP 2004-360461 A

  By the way, when the vehicle shifts from the supercharging state to the deceleration state, such as when the vehicle transitions from the acceleration state to the deceleration state, both solenoid valves are closed and the purge passages are closed. However, the purge gas stays in a portion from the portion of the intake passage where the first purge passage is connected to the combustion chamber. It is preferable from the viewpoint of emission control that the purge gas staying upstream from the throttle valve is introduced into the combustion chamber at the time of deceleration where the intake air amount is limited by the throttle valve and the air-fuel ratio becomes rich. Absent.

Hereinafter, means for solving the above-described problems and the effects thereof will be described.
A control apparatus for an on-vehicle internal combustion engine for solving the above problems includes a supercharger, a first purge passage connected to a portion of the intake passage upstream of the compressor of the supercharger, and a throttle in the intake passage. A vehicle-mounted internal combustion engine equipped with an evaporative fuel processing system that can select a second purge passage connected to a portion downstream of the valve as a purge route is a control target. The on-vehicle internal combustion engine control device includes a purge control unit that controls selection of the purge path, execution of purge, and stoppage of purge, and a supercharging control unit that controls the supercharger. In this on-vehicle internal combustion engine control device, the purge control unit selects the first purge passage as the purge path when supercharging is performed, performs purge, and when supercharging is not performed, While purging by selecting the second purge passage as the purge path, the purge is stopped when the operating state of the on-vehicle internal combustion engine shifts to the deceleration state. Further, in the control device for the on-vehicle internal combustion engine, when the operation state of the on-vehicle internal combustion engine shifts from the acceleration state in which the supercharging is performed to the deceleration state, the purge gas concentration is equal to or higher than a specified concentration. The supercharging control unit executes supercharger rotation speed suppression control for increasing the decrease rate of the rotation speed of the supercharger compared to when the purge gas concentration is less than a specified concentration.

  When the transition from the acceleration state in which supercharging is performed to the deceleration state is stopped, the purge is stopped, but even if the purge is stopped, from the portion of the intake passage where the first purge passage is connected to the combustion chamber The purge gas stays in this part. At this time, if the rotation speed of the supercharger remains high, the purge gas staying upstream of the throttle valve is sent to the downstream side of the throttle valve by the intake air sent from the compressor, and the air-fuel ratio becomes rich. Become.

  On the other hand, according to the above configuration, when the transition from the acceleration state to the deceleration state occurs and the purge gas concentration is equal to or higher than the specified concentration, the supercharger rotation speed suppression control is executed, and the supercharger The decrease speed of the rotation speed is increased. As a result, when the purge gas concentration is equal to or higher than the specified concentration and there is a concern that the air-fuel ratio becomes rich when the purge gas is sent downstream from the throttle valve, the rotational speed of the supercharger is quickly reduced. The purge gas can be prevented from being sent to the downstream side of the throttle valve. Therefore, according to the above configuration, it is possible to prevent the air-fuel ratio from becoming rich due to introduction of a gas having a high purge gas concentration into the combustion chamber when the acceleration state is shifted to the deceleration state.

The schematic diagram which shows schematic structure of each part of the control apparatus of a vehicle-mounted internal combustion engine, and the vehicle-mounted internal combustion engine which is the control object. The perspective view of a turbocharger. The fragmentary sectional view of a turbine housing. The flowchart which shows the flow of a series of processes concerning supercharger rotation speed suppression control which the control apparatus of a vehicle-mounted internal combustion engine performs. The schematic diagram which shows the state of a vehicle-mounted internal combustion engine when purging through the 1st purge channel | path. The schematic diagram which shows the state of the vehicle-mounted internal combustion engine when purging through the 2nd purge channel | path.

Hereinafter, an embodiment of a control device for an in-vehicle internal combustion engine will be described with reference to FIGS. First, the configuration of an in-vehicle internal combustion engine that is a control target of the control device will be described.
As shown in FIG. 1, four combustion chambers 110 are provided in an engine body 100 including a cylinder block and a cylinder head in an internal combustion engine 10 that is an in-vehicle internal combustion engine. An intake passage 120 and an exhaust passage 130 are connected to the engine body 100. The intake passage 120 has four downstream ends branched into the engine main body 100 such that each combustion chamber 110 provided in the engine main body 100 communicates with the branched end one by one. It is connected. Further, the exhaust passage 130 has an upstream end branched into four, and, like the intake passage 120, each combustion chamber 110 provided in the engine body 100 and this branched end are one by one. The engine body 100 is connected so as to communicate with each other.

  The internal combustion engine 10 includes a turbocharger 200 as a supercharger. Therefore, the turbine 210 of the turbocharger 200 is disposed in the middle of the exhaust passage 130, and the compressor 220 of the turbocharger 200 is disposed in the middle of the intake passage 120. A turbine wheel 211 is accommodated in the turbine 210, and a compressor wheel 221 connected to the turbine wheel 211 via a rotating shaft is accommodated in the compressor 220. As a result, the energy of the exhaust gas flowing through the exhaust passage 130 is recovered by the turbine 210, and the compressor 220 can be supercharged by the energy.

  As shown in FIG. 2, the turbocharger 200 is configured by combining a compressor housing 222 that constitutes a compressor 220, a bearing housing 270 that supports a rotating shaft, and a turbine housing 212 that constitutes a turbine 210. Yes. The bearing housing 270 is fastened to the compressor housing 222 with bolts. The turbine housing 212 is assembled to the bearing housing 270 by a clamp 280.

  As shown in FIG. 3, a turbine wheel 211 is accommodated in the turbine housing 212, and a scroll passage 213 extending so as to surround the turbine wheel 211 is formed in the turbine housing 212. The exhaust blown to the turbine wheel 211 through the scroll passage 213 is discharged to the exhaust passage 130 through the discharge passage 214.

  The turbine housing 212 is provided with a bypass passage 240. The bypass passage 240 is a passage that bypasses the turbine wheel 211 and connects the scroll passage 213 and the discharge passage 214. A waste gate valve 250 that closes the bypass passage 240 is provided in the turbine housing 212, and the bypass passage 240 can be opened and closed by driving the waste gate valve 250.

  When the waste gate valve 250 is opened and the bypass passage 240 is opened, the exhaust gas that has passed through the scroll passage 213 flows into the discharge passage 214 through the bypass passage 240, and the exhaust gas blown to the turbine wheel 211 is discharged. The amount is reduced. Therefore, when the bypass passage 240 is opened, rotation of the turbine wheel 211 and the compressor wheel 221 is suppressed, and supercharging is suppressed.

  The waste gate valve 250 is fixed to one end of a rotating shaft 251 that extends through the turbine housing 212 to the outside of the turbine housing 212. The rotation shaft 251 is rotatably supported by the turbine housing 212, and the waste gate valve 250 opens and closes the bypass passage 240 by rotating about the rotation shaft 251.

  As shown in FIGS. 2 and 3, a waste gate side link arm 252 is fixed to the other end of the rotating shaft 251 located outside the turbine housing 212. A columnar connecting pin 261 is fixed at a position away from the portion where the rotation shaft 251 is fixed on the waste gate side link arm 252 so that the central axis of the rotation shaft 251 and the central axis are parallel to each other. Yes.

  As shown in FIG. 2, an actuator 225 for driving the waste gate valve 250 is fixed to the compressor housing 222. The actuator 225 has a built-in motor, and drives the drive shaft 226 by the motor. An actuator side link arm 227 is fixed to the drive shaft 226. A connecting pin 261 is fixed at a position away from the portion where the drive shaft 226 is fixed in the actuator side link arm 227 so that the central axis of the drive shaft 226 is parallel to the central axis.

  In the turbocharger 200, the actuator side link arm 227 and the waste gate side link arm 252 are connected via a drive rod 260. Insertion holes are provided at both ends of the drive rod 260. The diameter of the insertion hole is slightly larger than the diameter of the connecting pin 261. One end of the drive rod 260 is assembled to the waste gate side link arm 252 so that the connection pin 261 is inserted into the insertion hole, and is prevented from being detached by an E-ring fitted in a groove provided at the distal end portion of the connection pin 261. Yes.

  The other end of the drive rod 260 is assembled with the actuator-side link arm 227 so that the connecting pin 261 is inserted into the insertion hole, and is prevented from being removed by an E-ring fitted in a groove provided at the tip of the connecting pin 261. Yes.

  As a result, when the drive shaft 226 is driven by the actuator 225 and the actuator side link arm 227 rotates about the drive shaft 226, the driving force of the actuator 225 is transmitted to the waste gate side link arm 252 via the drive rod 260. The Then, the waste gate side link arm 252 rotates about the rotation shaft 251 so that the waste gate valve 250 fixed to the rotation shaft 251 is close to or away from the bypass passage 240. Driven by. In the turbocharger 200, the bypass passage 240 can be opened and closed by driving the actuator 225 in this way.

  As shown in FIG. 1, an intercooler 140 that cools intake air is provided in a portion of the intake passage 120 downstream of the compressor 220. A surge tank 160 that reduces pulsation of intake air is provided in a portion of the intake passage 120 downstream of the intercooler 140. The intake passage 120 branches at a portion downstream of the surge tank 160 and is connected to the engine body 100. A throttle valve 150 that adjusts the amount of intake air is provided in a portion of the intake passage 120 between the surge tank 160 and the intercooler 140.

  The internal combustion engine 10 also includes an evaporative fuel processing system 300 including a canister 450 that collects evaporative fuel generated in the fuel tank 400. The canister 450 and the fuel tank 400 are connected via an evaporative fuel passage 410. Activated carbon is stored in the canister 450, and when the evaporated fuel generated in the fuel tank 400 is introduced into the canister 450 through the evaporated fuel passage 410, the evaporated fuel is adsorbed on the activated carbon and collected in the canister 450. It has become.

  In the evaporative fuel processing system 300, air is introduced from the outside into the canister 450, and the collected fuel is purged together with the air into the intake passage 120 of the operating internal combustion engine 10 as a purge gas, thereby collecting the canister 450. Restore ability. That is, the internal combustion engine 10 is equipped with an evaporative fuel processing system 300 that introduces evaporative fuel generated in the fuel tank 400 into the intake passage 120 for processing.

  The evaporative fuel processing system 300 switches the purge path for introducing the purge gas from the canister 450 to the intake passage 120 according to the situation, introduces the purge gas to the upstream side of the compressor 220 in the intake passage 120, or from the throttle valve 150. Also, a purge gas can be introduced into the downstream portion.

  Specifically, the evaporated fuel processing system 300 includes a switching valve 370 that switches the purge path by switching the communication mode of the purge path. The switching valve 370 houses a valve body 376 that switches between communication and blocking of the ports 371, 372, and 373 inside a housing 375 in which the first port 371, the second port 372, and the third port 373 are formed. Is.

  As shown in FIG. 1, the valve body 376 is formed with an intra-valve passageway. By rotating the valve body 376 within the housing 375, the ports 371, 372, and 373 can be connected and disconnected. Can be switched. The valve body 376 is driven by a motor, and the direction of the valve body 376 can be controlled by controlling the motor.

  A first port 371 of the switching valve 370 is connected to a portion of the intake passage 120 upstream of the compressor 220 by a first purge passage 381. The second port 372 of the switching valve 370 is connected to the downstream side of the throttle valve 150 in the intake passage 120 by the second purge passage 382, and the third port 373 is connected to the canister 450 by the upstream purge passage 340. It is connected. That is, the first purge passage 381 is a passage that communicates a portion of the intake passage 120 upstream of the compressor 220 with the upstream purge passage 340. The second purge passage 382 is a passage that communicates a portion of the intake passage 120 downstream of the throttle valve 150 with the upstream purge passage 340.

  A purge control valve 360 that closes the upstream purge passage 340 when the valve is closed is provided in the middle of the upstream purge passage 340. In addition, a purge pump 350 that sucks purge gas from the canister 450 side and sends it to the switching valve 370 side is also provided at a portion upstream of the purge control valve 360 in the upstream purge passage 340.

  Control of each part of the internal combustion engine 10 including control of the direction of the valve body 376 in the switching valve 370 is performed by the control device 500. That is, the control device 500 is a control device for an in-vehicle internal combustion engine. The control device 500 is connected to an accelerator position sensor 510 that detects an accelerator opening that is an accelerator operation amount, a vehicle speed sensor 520 that detects a vehicle speed that is a vehicle speed, and an air-fuel ratio sensor 530 that detects an air-fuel ratio. Yes. Further, the control device 500 includes a rotation speed sensor 540 that detects the rotation speed of the turbocharger 200 that is the rotation speed of the compressor wheel 221 per unit time, and a portion of the intake passage 120 that is downstream of the compressor 220. Also connected is a supercharging pressure sensor 550 for detecting the intake pressure at.

  The control device 500 controls the internal combustion engine 10 based on information detected by these sensors. Specifically, based on the vehicle speed detected by the vehicle speed sensor 520 and the accelerator opening detected by the accelerator position sensor 510, the magnitude of the required torque is estimated, and the intake required for generating the estimated torque The opening degree of the throttle valve 150 is adjusted to realize the air amount. Then, the injector 560 is controlled so as to supply an amount of fuel corresponding to the amount of intake air. When determining the fuel injection amount that is the amount of fuel injected from the injector 560, the air-fuel ratio is corrected by referring to the air-fuel ratio detected by the air-fuel ratio sensor 530 so that the air-fuel ratio approaches the stoichiometric air-fuel ratio. Perform feedback control. In the air-fuel ratio feedback control, a purge gas concentration learning value that is an index of the purge gas concentration, which is the concentration of fuel in the purge gas introduced by the purge, is calculated based on the magnitude of the air-fuel ratio deviation during the purge. To do. The purge gas concentration learning value becomes larger as the purge gas concentration is higher. In the internal combustion engine 10, one in-cylinder injector 560 that supplies fuel directly to the combustion chamber 110 of the internal combustion engine 10 is provided for each combustion chamber 110. Further, the control device 500 controls the ignition timing in each combustion chamber 110 by controlling the spark plugs 570 provided one by one in each combustion chamber 110 in order to realize the required torque.

  The control device 500 also controls supercharging by the turbocharger 200 by opening and closing the waste gate valve 250 in accordance with the control of the throttle valve 150, the injector 560, and the spark plug 570 as described above. This supercharging control is performed by a supercharging control unit 502 provided in the control device 500. When the requested torque is large and there is a supercharging request, the supercharging control unit 502 closes the waste gate valve 250 and performs supercharging with the turbocharger 200. On the other hand, when the required torque is small, the waste gate valve 250 is not closed, and the exhaust gas flows around the turbine 210 to suppress supercharging.

  When supercharging is performed by closing the waste gate valve 250, the supercharging control unit 502 drives the actuator 225 to press the waste gate valve 250 against the portion of the turbine housing 212 where the bypass passage 240 is open. Keep in state. On the other hand, when the waste gate valve 250 is not closed and supercharging is not performed, the driving of the actuator 225 is stopped so that the waste gate valve 250 freely rotates about the rotation shaft 251. Accordingly, the waste gate valve 250 is pushed by the exhaust from the bypass passage 240 side and opens.

Further, the control device 500 includes a purge control unit 501 that controls each part of the evaporated fuel processing system 300, and also controls each part of the evaporated fuel processing system 300.
Next, with reference to FIG. 4, the flow of processing relating to control of the evaporated fuel processing system 300 and supercharging control executed by the control device 500 will be described.

  The control device 500 repeatedly executes a series of processes shown in FIG. 4 during operation of the internal combustion engine 10. As shown in FIG. 4, when this series of processes is started, the control device 500 first determines in step S100 whether or not the accelerator opening is equal to or greater than a predetermined opening ThA. The size of the predetermined opening ThA is set to such a size that it can be determined that the operating state of the internal combustion engine 10 is in a deceleration state or a stopped state based on the fact that the accelerator opening is less than the predetermined opening ThA. Has been.

  If it is determined in step S100 that the accelerator opening is equal to or greater than the predetermined opening ThA (step S100: YES), that is, if the operating state of the internal combustion engine 10 is an acceleration state or a cruise state at a constant speed, control is performed. Apparatus 500 proceeds with the process to step S110.

  In step S110, control device 500 determines whether or not there is a supercharging request. Whether or not there is a supercharging request is determined based on whether or not the requested torque is large. That is, when the required torque estimated based on the vehicle speed and the accelerator opening is large, it is determined that there is a supercharging request.

  If it is determined in step S110 that there is a supercharging request (step S110: YES), control device 500 advances the process to step S120. In step S120, the purge control unit 501 in the control device 500 selects the first purge passage 381 as the purge route, and executes the purge.

  Specifically, as shown in FIG. 5, the purge control unit 501 controls the valve body 376 of the switching valve 370 in a direction in which the third port 373 and the first port 371 communicate with each other. At this time, the second port 372 is closed by the valve body 376. That is, in the process of step S120, the valve body 376 of the switching valve 370 is controlled so as to communicate the upstream purge passage 340 and the first purge passage 381. As a result, a purge path is formed by the upstream purge passage 340 and the first purge passage 381. Then, the purge control unit 501 drives the purge pump 350 to send the purge gas to the intake passage 120 side through the upstream purge passage 340. The purge gas introduced into the third port 373 of the switching valve 370 through the upstream purge passage 340 is introduced into a portion upstream of the compressor 220 in the intake passage 120 through the first purge passage 381 connected to the first port 371. Will come to be. The purge gas thus introduced into the intake passage 120 is introduced into the combustion chamber 110 together with the intake air flowing through the intake passage 120 and is used for combustion in the combustion chamber 110.

  If step S120 is performed, the control apparatus 500 will perform supercharging control in step S130 next. Here, the supercharging control unit 502 in the control device 500 opens and closes the waste gate valve 250 according to the intake pressure detected by the supercharging pressure sensor 550 to control the intake pressure. Specifically, as described above, the actuator 225 is driven to hold the waste gate valve 250 in a state where it is pressed against the portion of the turbine housing 212 where the bypass passage 240 is open. However, when the intake pressure becomes excessively high, the driving of the actuator 225 is stopped and the waste gate valve 250 is opened to prevent the intake pressure from becoming excessively high.

When the process of step S130 is performed in this way, the control device 500 temporarily ends this series of processes.
On the other hand, when it determines with there being no supercharging request | requirement in step S110 (step S110: NO), the control apparatus 500 advances a process to step S140. In step S140, the purge control unit 501 in the control device 500 selects the second purge passage 382 as the purge route, and executes the purge.

  Specifically, as shown in FIG. 6, the purge control unit 501 controls the valve body 376 of the switching valve 370 in a direction in which the third port 373 and the second port 372 are communicated. At this time, the first port 371 is closed by the valve body 376. That is, in the process of step S140, the valve body 376 of the switching valve 370 is controlled so as to communicate the upstream purge passage 340 and the second purge passage 382. As a result, a purge path is formed by the upstream purge passage 340 and the second purge passage 382. Then, the purge control unit 501 drives the purge pump 350 to send the purge gas to the intake passage 120 side through the upstream purge passage 340. The purge gas introduced into the third port 373 of the switching valve 370 through the upstream purge passage 340 passes through the second purge passage 382 connected to the second port 372 to a portion downstream of the throttle valve 150 in the intake passage 120. Will be introduced. The purge gas thus introduced into the intake passage 120 is introduced into the combustion chamber 110 together with the intake air flowing through the intake passage 120 and is used for combustion in the combustion chamber 110.

  If step S140 is performed, the control apparatus 500 will stop supercharging control in step S150. If supercharging control is not performed at this time, the state where supercharging control is stopped is maintained as it is. When the supercharging control is stopped, the actuator 225 is not driven. As a result, the waste gate valve 250 is pushed and opened by the exhaust gas flowing through the bypass passage 240, so that the exhaust gas bypasses the turbine wheel 211 and supercharging is not performed.

When the process of step S140 is performed in this way, the control device 500 temporarily ends this series of processes.
When it is determined in step S100 that the accelerator opening is less than the predetermined opening ThA (step S100: NO), that is, when the operating state is the deceleration state or the stop state, the control device 500 performs the process. Proceed to S160.

  In step S160, control device 500 stops the supercharging control and stops the purge. That is, here, the supercharging control unit 502 stops the supercharging control similarly to step S150. Further, the purge control unit 501 stops the purge.

  As shown in FIG. 1, when stopping the purge, the purge control unit 501 controls the switching valve 370 so that the valve passage in the valve element 376 does not communicate with any of the ports 371, 372, and 373. At the same time, the purge control valve 360 is closed and the upstream purge passage 340 is closed to prevent purging.

  When the supercharging control and the purge are thus stopped through step S160, the control device 500 advances the process to step S170, and determines whether or not the supercharger rotational speed is equal to or higher than the predetermined rotational speed NcA in step S170. If the compressor wheel 221 is rotating at this time, the compressor wheel 221 is rotating by inertia. Therefore, the size of the predetermined rotational speed NcA is set to a size that can be estimated from the acceleration state to the deceleration state based on the supercharger rotational speed being equal to or higher than the predetermined rotational speed NcA. Has been.

  When it is determined in step S170 that the supercharger rotational speed is equal to or higher than the predetermined rotational speed NcA (S170: YES), the control device 500 advances the process to step S180, and in step S180, the purge gas concentration learning value is a predetermined value. It is determined whether it is DpA or more. The magnitude of the predetermined value DpA is set to such a magnitude that it can be determined that the purge gas concentration is equal to or higher than the specified concentration based on the purge gas concentration learned value being equal to or higher than the predetermined value DpA. The specified concentration is a concentration at which the air-fuel ratio may become rich beyond the allowable range when the purge gas is sent downstream of the throttle valve 150 by the action of the compressor wheel 221 that rotates by inertia.

  When it is determined in step S170 that the supercharger rotation speed is less than the predetermined rotation speed NcA (S170: NO), or when it is determined in step S180 that the purge gas concentration learned value is less than the predetermined value DpA (step S180: NO). ), The control device 500 once ends this series of processes. That is, in this case, the supercharging control and the purge are stopped.

  On the other hand, when it is determined in step S180 that the purge gas concentration learning value is equal to or greater than the predetermined value DpA (step S180: YES), control device 500 advances the process to step S190.

  In step S190, the control device 500 executes supercharger rotation speed suppression control. In the supercharger suppression control, the supercharging control unit 502 continues to drive the actuator 225 in the direction in which the waste gate valve 250 is opened. As a result, when the supercharger rotation speed suppression control is being executed, the waste gate valve 250 is opened larger than when the actuator 225 is not driven and opened unexpectedly, and is kept fully open. Is done.

When the process of step S190 is performed in this way, the control device 500 temporarily ends this series of processes.
Next, the effect | action by which the control apparatus 500 repeatedly performs the series of processes demonstrated with reference to FIG. 4 is demonstrated.

  When the accelerator opening is equal to or greater than the predetermined opening ThA (step S100: YES), purge is executed by the purge control unit 501. As a result, the evaporated fuel adsorbed on the activated carbon stored in the canister 450 is introduced into the intake passage 120 as a purge gas and is processed by combustion in the combustion chamber 110. Therefore, the ability of the canister 450 to collect evaporated fuel is increased. Can be recovered.

  Further, when purging, a purge path is selected according to whether or not a supercharging request is made, and the purge control unit 501 performs the purging by selecting the first purge path 381 as the purge path when supercharging is performed. When the supply is not performed, the purge is performed by selecting the second purge passage 382 as the purge path.

  By the way, when the operating state of the internal combustion engine 10 is an acceleration state and supercharging by the turbocharger 200 is performed, the purge gas is introduced into the intake passage 120 through the first port 371 as shown in FIG. ing. When shifting from the state of supercharging by the turbocharger 200 to the decelerating state as in the case of shifting from the accelerating state to the decelerating state, as shown in FIG. The first port 371 is closed and the purge is stopped. At this time, although the purge is stopped, the purge gas stays in the portion from the portion of the intake passage 120 where the first purge passage 381 is connected to the throttle valve 150. At this time, if the rotation speed of the compressor wheel 221 remains high, the purge gas staying upstream of the throttle valve 150 is sent to the downstream side of the throttle valve 150 by the intake air sent from the compressor 220, The fuel ratio becomes rich.

  On the other hand, in the control device 500 of the above embodiment, when the accelerator opening is less than the predetermined opening ThA (step S100: NO), and the supercharger rotation speed is equal to or higher than the predetermined rotation speed NcA (step S170: YES), the supercharger rotation speed suppression control is executed based on the purge gas concentration learning value. These conditions are satisfied when the compressor wheel 221 is inertial and is rotating at a rotational speed equal to or higher than the predetermined rotational speed NcA, although it is not in an accelerated state or a cruise state, and the operating state of the internal combustion engine 10 is in an accelerated state. This is the case immediately after the transition to the deceleration state.

  According to this control device 500, when the operation state of the internal combustion engine 10 thus shifts from the acceleration state to the deceleration state, the purge gas concentration learning value is equal to or greater than the predetermined value DpA (step S180: YES), that is, the purge gas concentration is The supercharger rotation speed suppression control is executed on condition that the concentration is not less than the specified concentration (step S190).

  When the supercharger rotation speed suppression control is executed, the waste gate valve 250 is held fully open, so that the purge gas concentration is less than the specified concentration, and compared with the case where the waste gate valve 250 is opened in an unexpected manner. The opening degree of the waste gate valve 250 increases, and the amount of exhaust that bypasses the compressor wheel 221 increases. As a result, the rate of decrease in the rotational speed of the compressor 220 is higher than when the purge gas concentration is less than the specified concentration and the waste gate valve 250 is opened unexpectedly.

By such an operation, the following effects can be obtained according to the control device 500 described above.
(1) When the transition from the acceleration state to the deceleration state occurs, if the purge gas concentration is equal to or higher than the specified concentration, the supercharger rotation speed suppression control is executed, and the decrease speed of the rotation speed of the compressor wheel 221 is increased. . Accordingly, when the purge gas concentration is equal to or higher than the specified concentration and there is a concern that the air-fuel ratio becomes rich when the purge gas is sent downstream from the throttle valve 150, the rotation speed of the compressor wheel 221 is rapidly reduced. Therefore, it is possible to suppress the purge gas from being sent to the downstream side of the throttle valve 150. Therefore, it is possible to prevent the air-fuel ratio from becoming rich due to the introduction of a gas having a high purge gas concentration into the combustion chamber 110 when shifting from the acceleration state to the deceleration state.

In addition, said embodiment can also be implemented with the following forms which changed this suitably.
If the purge gas concentration can be detected without depending on the purge gas concentration learning value, it may be determined whether to execute the supercharger rotation speed suppression control according to the detected purge gas concentration. Good.

  ・ The turbocharger is not limited to a turbocharger. For example, an internal combustion engine that employs an electric supercharger that operates the compressor 220 with a motor as a supercharger, or an engine-driven supercharger that operates the compressor 220 using a part of the driving force of the internal combustion engine 10. Even the engine 10 can achieve the same effects as the above embodiment.

  For example, in the case of an electric supercharger, if the motor is controlled so as to act as a brake for reducing the rotational speed in the supercharger rotation speed suppression control, the compressor 220 is stopped immediately. Good.

  In the case of an engine-driven supercharger, the compressor 220 may be provided with a brake, and the brake may be applied in the supercharger rotation speed suppression control to reduce the rotation speed.

  DESCRIPTION OF SYMBOLS 10 ... Internal combustion engine, 100 ... Engine body, 110 ... Combustion chamber, 120 ... Intake passage, 130 ... Exhaust passage, 140 ... Intercooler, 150 ... Throttle valve, 160 ... Surge tank, 200 ... Turbocharger, 210 ... Turbine, 211 ... turbine wheel, 212 ... turbine housing, 213 ... scroll passage, 214 ... discharge passage, 220 ... compressor, 221 ... compressor wheel, 222 ... compressor housing, 225 ... actuator, 226 ... drive shaft, 227 ... actuator side link arm, 240 ... Bypass passage, 250 ... Wastegate valve, 251 ... Rotating shaft, 252 ... Wastegate side link arm, 260 ... Drive rod, 261 ... Connecting pin, 270 ... Bearing housing, 280 ... Clamp, 300 ... Steaming Fuel treatment system, 340 ... upstream purge passage, 350 ... purge pump, 360 ... purge control valve, 370 ... switching valve, 371 ... first port, 372 ... second port, 373 ... third port, 375 ... housing, 376 ... Valve, 381 ... First purge passage, 382 ... Second purge passage, 400 ... Fuel tank, 410 ... Evaporative fuel passage, 450 ... Canister, 500 ... Control device, 501 ... Purge control section, 502 ... Supercharging control section , 510 ... Accelerator position sensor, 520 ... Vehicle speed sensor, 530 ... Air-fuel ratio sensor, 540 ... Rotational speed sensor, 550 ... Supercharging pressure sensor, 560 ... Injector, 570 ... Spark plug.

Claims (1)

A supercharger, a first purge passage connected to a portion of the intake passage upstream of the compressor of the supercharger, and a second purge connected to a portion of the intake passage downstream of the throttle valve An in-vehicle internal combustion engine equipped with an evaporative fuel processing system that can select a passage as a purge route is a control target,
A purge control unit that controls selection of the purge path, execution of purge, and stoppage of purge;
A supercharging control unit for controlling the supercharger,
The purge control unit performs the purge by selecting the first purge passage as the purge path when supercharging is performed, and selects the second purge path as the purge path when supercharging is not performed. The purge is stopped when the operating state of the in-vehicle internal combustion engine shifts to the deceleration state,
When the operating state of the in-vehicle internal combustion engine shifts from an acceleration state in which supercharging is performed to a deceleration state, the supercharging control unit defines the purge gas concentration on condition that the purge gas concentration is equal to or higher than a specified concentration. A control device for an on-vehicle internal combustion engine that performs supercharger rotation speed suppression control that increases a decrease speed of the rotation speed of the supercharger more than when the concentration is less than the concentration.

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