JP2012097678A - Open and close control device of waste gate valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the occurrence of a turbo lag associated with an opening/closing operation of a waste gate valve.SOLUTION: An opening/closing control device of the waste gate valve 210 which is located on a bypass passage 111 bypassing a turbine wheel 101 includes: a negative pressure actuator 230 for opening and closing the waste gate valve 210; a negative pressure source 260 driven by an engine 1; a shut-off valve 240 inserted between the negative pressure actuator 230 and the negative pressure source 260; and a shut-off valve control unit 320 for controlling the opening/closing of the shut-off valve 240. In addition, the shut-off valve control unit 320 closes the shut-off valve 240 when a stop condition of the engine 1 is satisfied.

Description

  The present invention relates to an opening / closing control device for a wastegate valve mounted on a vehicle.

  Conventionally, a turbocharger is mounted on a vehicle in order to improve the output of an internal combustion engine such as an engine. Further, in the supercharger, a wastegate valve is disposed in a bypass passage that bypasses the turbine wheel in order to prevent the supercharging pressure from becoming excessive. Various devices and methods for controlling the opening and closing of the waste gate valve have been proposed.

  For example, when the internal combustion engine is operated in a first operating region where the intake air flow rate is equal to or higher than a predetermined gas flow rate threshold, the opening of the wastegate valve is controlled so that the turbine passage gas flow rate becomes the gas flow rate threshold value. A control device that closes a bypass passage by a wastegate valve when the internal combustion engine is operated in a second operation region in which the intake air flow rate is smaller than a gas flow rate threshold is disclosed (see Patent Document 1). According to this control device, the exhaust pressure can be reduced to reduce the exhaust loss, and the acceleration response performance of the internal combustion engine can be ensured.

JP 2010-38093 A

  However, when the drive source that drives the wastegate valve is a negative pressure actuator, a time lag occurs until the wastegate valve transitions from the fully open state to the fully closed state when restarting after idling stop of the engine. There is a risk of drivability degradation.

  That is, when the driving source for driving the wastegate valve is a negative pressure actuator, when the engine stops idling, the negative pressure supplied to the negative pressure actuator disappears, and the wastegate valve is fully opened. Further, when the engine is restarted and accelerated, turbo lag is generated until the wastegate valve transitions from the fully open state to the fully closed state. Therefore, there is a risk that drivability will be lowered because a delay in response of supercharging occurs.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a wastegate valve opening / closing control device capable of suppressing the generation of a turbo lag associated with the opening / closing operation of the wastegate valve.

  In order to solve the above-described problems, the opening / closing control device for a waste gate valve according to the present invention is configured as follows.

  That is, the opening / closing control device for the waste gate valve according to the present invention is a waste gate valve opening / closing control device disposed in a bypass passage that bypasses the turbine wheel, and a negative pressure actuator that opens and closes the waste gate valve; A negative pressure source driven by an internal combustion engine, a cutoff valve interposed between the negative pressure actuator and the negative pressure source, and a cutoff valve control means for controlling opening and closing of the cutoff valve, The shut-off valve control means closes the shut-off valve when the internal combustion engine stop condition is satisfied.

  According to the opening / closing control device for a wastegate valve having such a configuration, when the stop condition of the internal combustion engine is satisfied, the shutoff valve interposed between the negative pressure actuator and the negative pressure source is closed, Since negative pressure is maintained between the shut-off valve and the negative pressure actuator, occurrence of turbo lag can be suppressed.

  That is, for example, during the period from when the idling stop condition is satisfied to when the internal combustion engine is stopped, the shut-off valve is closed, and negative pressure is maintained between the shut-off valve and the negative pressure actuator. And, for example, when restarting after idling is stopped, since the negative pressure that is the driving source of the negative pressure actuator is maintained between the shutoff valve and the negative pressure actuator, the waste gate valve is opened by the negative pressure actuator. It can be opened and closed in a short period of time. Therefore, since the wastegate valve can be closed when restarting after idling is stopped, the occurrence of turbo lag can be suppressed.

  In the wastegate valve opening / closing control apparatus according to the present invention, it is preferable that the stop condition of the internal combustion engine is an idling stop condition for stopping idling of the internal combustion engine.

  According to the opening / closing control device for a wastegate valve having such a configuration, since the stop condition of the internal combustion engine is an idling stop condition for stopping idling of the internal combustion engine, generation of a turbo lag is caused at the restart after the idling stop. Can be suppressed.

  That is, since the period from the idling stop to the restart is shorter than the period from the end of trip of the vehicle to the start of trip (between the ignition switch OFF and the ignition switch ON), the shut-off valve Since the negative pressure can be maintained between the negative pressure actuator and the negative pressure actuator, generation of turbo lag can be suppressed.

  Further, the wastegate valve opening / closing control device according to the present invention is configured such that the shutoff valve control means opens the shutoff valve when a preset open condition is satisfied after the internal combustion engine is restarted. It is preferable to do.

  According to the opening / closing control device for a wastegate valve having such a configuration, the shut-off valve is opened when a preset opening condition is satisfied after the internal combustion engine is restarted. Is set to an appropriate condition, the shutoff valve can be opened at an appropriate timing.

  Here, when the timing for opening the shut-off valve is too early, the negative pressure source operates after the shut-off valve is opened (exactly, a negative pressure can be secured by the negative pressure source). Since the negative pressure held between the shut-off valve and the negative pressure actuator is released during the period until it reaches the state), a turbo lag is generated. On the other hand, when the timing for opening the shut-off valve is too late, the negative pressure source can ensure a negative pressure, but the gap between the shut-off valve and the negative pressure actuator is not reached. As a result, the negative pressure held in the valve is released, so that the force for closing the shut-off valve is weakened. Therefore, in order to suppress the occurrence of turbo lag, it is necessary to open the shut-off valve at an appropriate timing.

  In the opening / closing control device for a waste gate valve according to the present invention, it is preferable that the opening condition is a condition that a negative pressure of the negative pressure source can be secured.

  According to the opening / closing control device for a wastegate valve having such a configuration, since the opening condition is a condition that the negative pressure of the negative pressure source can be secured, the shut-off valve is opened at an appropriate timing. Can do.

  That is, when the shutoff valve is opened before the negative pressure source can secure a negative pressure, the negative pressure source can secure the negative pressure after the shutoff valve is opened. Since the negative pressure held between the shut-off valve and the negative pressure actuator is released during the period until the state is reached, turbo lag is generated. On the contrary, when the shutoff valve is opened after the negative pressure source can secure the negative pressure, the negative pressure source can ensure the negative pressure. Since the negative pressure held between the shut-off valve and the negative pressure actuator is released, the force for closing the shut-off valve is weakened.

  In the waste gate valve opening / closing control apparatus according to the present invention, it is preferable that the opening condition is a condition that a predetermined time threshold or more has elapsed since the internal combustion engine was restarted.

  According to the opening / closing control device for a wastegate valve having such a configuration, since the opening condition is a condition that a predetermined time threshold or more has elapsed since the internal combustion engine was restarted, the time threshold By appropriately setting, the shutoff valve can be opened at an appropriate timing.

  For example, the time required for the pressure on the negative pressure source side of the shut-off valve to coincide with the pressure on the negative pressure actuator side of the shut-off valve from the time when the internal combustion engine is restarted is obtained by experiments or the like. This time may be set as the time threshold. In this case, the pressure on the negative pressure source side of the shut-off valve is equal to the pressure on the negative pressure actuator side of the shut-off valve when the time threshold elapses from the time when the internal combustion engine is restarted. Match. This timing is the earliest timing at which the negative pressure actuator can be opened and closed by the negative pressure source. Accordingly, since the shut-off valve is opened at this timing, the shut-off valve can be opened at an appropriate timing.

  Further, in the opening / closing control device for a waste gate valve according to the present invention, the opening condition is that the pressure on the negative pressure source side of the cutoff valve is equal to or lower than the pressure on the negative pressure actuator side of the cutoff valve. It is preferable that

  According to the opening / closing control device for a wastegate valve having such a configuration, the opening condition is that the pressure on the negative pressure source side of the shutoff valve is equal to or lower than the pressure on the negative pressure actuator side of the shutoff valve. Therefore, the shut-off valve can be opened at an appropriate timing.

  That is, the shutoff valve is opened at a timing when the pressure on the negative pressure source side of the shutoff valve coincides with the pressure on the negative pressure actuator side of the shutoff valve. This timing is the earliest timing at which the negative pressure actuator can be opened and closed by the negative pressure source. Accordingly, since the shut-off valve is opened at this timing, the shut-off valve can be opened at an appropriate timing.

  According to the opening / closing control apparatus for a wastegate valve according to the present invention, when the stop condition of the internal combustion engine is established, the shutoff valve interposed between the negative pressure actuator and the negative pressure source is closed, Since negative pressure is maintained between the shut-off valve and the negative pressure source, generation of turbo lag can be suppressed.

It is a block diagram which shows an example of the engine by which the wastegate valve which concerns on this invention is arrange | positioned. It is a block diagram which shows an example of the drive mechanism of the wastegate valve | bulb shown in FIG. It is sectional drawing which shows an example of the XX cross section of FIG. It is a perspective view which shows an example of a structure of the wastegate valve and link mechanism shown in FIG. FIG. 3 is a functional configuration diagram illustrating an example of a functional configuration of an ECU that controls operations of a waste gate valve and a shut-off valve illustrated in FIG. 2. It is a flowchart which shows an example of operation | movement of the cutoff valve control part shown in FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

-Engine 1-
FIG. 1 is a configuration diagram showing an example of an engine 1 in which a wastegate valve 210 according to the present invention is disposed. The engine 1 is, for example, a four-cylinder diesel engine, and includes an intake manifold 2 for distributing intake air to each cylinder and an exhaust manifold 3 for collecting exhaust gas discharged from each cylinder. It is connected. Here, the engine 1 corresponds to an “internal combustion engine” in the invention described in the claims.

  An intake passage 4 is connected to the inlet of the intake manifold 2 to take air from the atmosphere and lead it to the intake manifold 2. An air cleaner 6 is disposed at the inlet of the intake passage 4. Further, a throttle valve 7 for adjusting the intake air amount of the engine is disposed upstream of the intake manifold 2 (upstream of the intake flow).

  The throttle valve 7 is driven by a throttle motor (not shown). Further, the opening degree of the throttle valve 7 is detected by a throttle opening degree sensor 32. The throttle opening degree of the throttle valve 7 is controlled by an ECU (Electronic Control Unit) 300. On the other hand, an exhaust passage 5 is connected to the outlet of the exhaust manifold 3. A catalyst 9 is disposed in the middle of the exhaust passage 5.

  Further, the engine 1 is equipped with a turbocharger 100 and an EGR device 120. Hereinafter, these configurations will be sequentially described.

-Turbocharger 100-
The turbocharger 100 includes a turbine wheel 101, a compressor impeller 102, and a connecting shaft 103. The turbine wheel 101 is disposed in the exhaust passage 5 and is rotationally driven by exhaust energy. The compressor impeller 102 is disposed in the intake passage 4. The connecting shaft 103 connects the turbine wheel 101 and the compressor impeller 102 integrally.

  The turbine wheel 101 disposed in the exhaust passage 5 is rotationally driven by the energy of the exhaust, and accordingly, the compressor impeller 102 disposed in the intake passage 4 is rotationally driven. Then, the intake air is supercharged by the rotation of the compressor impeller 102, and the supercharged air is forcibly sent into the combustion chamber of each cylinder of the engine 1. In addition, an intercooler 8 for cooling air supercharged by the compressor impeller 102 is interposed in the intake passage 4 on the downstream side (downstream of the intake air flow) of the compressor impeller 102.

  Further, in the turbocharger 100, as shown in FIG. 2, an exhaust bypass passage 111 is formed in the turbine housing 110, and a waste gate valve 210 that opens and closes the exhaust bypass passage 111 is disposed. Here, the exhaust bypass passage 111 corresponds to a “bypass passage” in the invention described in the claims. Details of the wastegate valve 210, the link mechanism 220, and the drive mechanism 200 will be described later with reference to FIGS.

-EGR device 120-
The EGR (Exhaust Gas Recirculation) device 120 includes an EGR passage (exhaust gas recirculation passage) 121. An end of one side (here, the upper side) of the EGR passage 121 is connected to the intake passage 4 between the intake manifold 2 and the throttle valve 7. The other end (here, the lower side) of the EGR passage 121 is connected to the exhaust manifold 3, and a part of the exhaust gas (EGR gas) is introduced into the intake passage 4 through the EGR passage 121. The EGR device 120 can lower the combustion temperature and reduce the amount of NOx produced by returning EGR gas (a gas having a higher specific heat and a smaller amount of oxygen than air) to the intake passage 4.

  An EGR valve 124 that opens and closes the EGR passage 121 is interposed in the middle of the EGR passage 121. In addition, an EGR cooler 122 that cools the EGR gas flowing in the EGR passage 121 is interposed on the upstream side (exhaust side) of the EGR valve 124 in the EGR passage 121. The EGR gas is cooled by the EGR cooler 122 to increase the density, and the EGR rate can be increased while securing the intake air amount.

  Further, the EGR device 120 is provided with an EGR bypass passage 121a that bypasses the EGR cooler 122 and flows EGR gas. A switching control valve 123 that adjusts the opening degree of the EGR passage 121 and the opening degree of the EGR bypass passage 121a is provided at a connection portion (a connection portion on the downstream side of the EGR gas flow) between the EGR bypass passage 121a and the EGR passage 121. It is installed.

-Wastegate valve device-
Next, the configuration of the waste gate valve device that opens and closes the waste gate valve 210 will be described with reference to FIGS. FIG. 2 is a configuration diagram illustrating an example of the drive mechanism 200 of the wastegate valve 210 illustrated in FIG. 1. 3 is a cross-sectional view taken along the line XX of FIG. In FIG. 3, a part of the turbine housing 110 is omitted. FIG. 4 is a perspective view showing an example of the configuration of the wastegate valve 210 and the link mechanism 220 shown in FIG.

  As shown in FIG. 2, the wastegate valve device includes a wastegate valve 210, a link mechanism 220, and a drive mechanism 200. The drive mechanism 200 opens and closes the wastegate valve 210 via the link mechanism 220.

  Before describing the wastegate valve device, a part of the configuration of the turbine housing 110 will be described first with reference to FIGS. 2 and 3. An exhaust bypass passage 111 that bypasses the turbine wheel 101 is formed in the turbine housing 110. The exhaust bypass passage 111 includes a circular waste gate hole 111a that passes through the wall body 110b of the turbine housing 110, and the exhaust gate is connected to the upstream side of the turbine wheel 101 (upstream side of the exhaust gas flow) and the exhaust gas by the waste gate hole 111a. The outlet passage 110a communicates with the outlet passage 110a. In addition, a valve seat (valve seat) 112 is provided at a peripheral portion of the waste gate hole 111a (peripheral portion on the exhaust gas outlet passage 110a side).

-Wastegate valve 210-
Next, the structure of the wastegate valve 210 will be described with reference to FIG. The wastegate valve 210 controls the amount of EGR gas flowing out into the exhaust bypass passage 111 by adjusting the opening degree of the wastegate hole 111a, and includes a valve body 211, a biasing member 212, a support pin 213, In addition, a stopper 214 is provided.

  The valve body 211 is a disk-like member that is disposed at a position facing the valve seat 112 provided in the turbine housing 110 and opens or closes the exhaust bypass passage 111 by being seated on or separated from the valve seat 112. Further, the valve body 211 has a through hole 211 a formed at a substantially central portion of the valve body 211, a support pin 213 is inserted into the through hole 211 a, and the valve body 211 is supported by the support pin 213. .

  The biasing member 212 is interposed between the valve body 211 and the distal end portion of the swing arm 221 and biases the valve body 211 in a direction away from the distal end portion of the swing arm 221.

  The support pin 213 is disposed at the tip of the swing arm 221 in a direction perpendicular to the swing arm 221. That is, the valve body 211 is attached to the support pin 213 so as to be movable toward and away from the swing arm 221 in the valve opening / closing direction (left-right direction in FIG. 2). Here, since the inner diameter of the through hole 211a formed in the valve body 211 is larger than the outer diameter of the support pin 213 by a predetermined amount, the valve body 211 can slide with respect to the support pin 213. And tiltable.

  The stopper 214 regulates the movement of the valve body 211 in a direction away from the swing arm 221. That is, when an external force (pressing force toward the swing arm 221) is not applied to the valve body 211, the valve body 211 comes into contact with the stopper 214 while being pressed by the biasing force of the biasing member 212.

-Link mechanism 220-
Next, the link mechanism 220 will be described with reference to FIGS. The link mechanism 220 transmits the driving force from the drive mechanism 200 to the wastegate valve 210, and includes a swing arm 221, a support shaft 222, a link shaft 223, a drive rod 224, and a connecting pin 225. Yes.

  The swing arm 221 drives the wastegate valve 210 in a direction in which the wastegate valve 210 is brought into contact with and separated from the valve seat 112 provided in the turbine housing 110 (left and right direction in FIG. 2). 4, the lower end portion is locked to the wastegate valve 210, and the other end portion (the upper end portion in FIGS. 2 and 4) is fixed to the support shaft 222. That is, the swing arm 221 is configured to rotate about the support shaft 222 when the support shaft 222 rotates.

  The support shaft 222 is a shaft that is rotatably supported by the turbine housing 110, and transmits the driving force from the link shaft 223 to the swing arm 221. The swing arm 221 is centered on the support shaft 222. It is intended to rotate. One end (right end in FIG. 4) of the support shaft 222 is fixed to one end of the swing arm 221, and the other end (left end in FIG. 4) is fixed to one end of the link shaft 223. Has been.

  The link shaft 223 transmits the driving force from the drive rod 224 to the support shaft 222, and is rotatably engaged with one end of the drive rod 224 at one end (upper end in FIG. 4). The other end (the lower end in FIG. 4) is fixed to the one end (the left end in FIG. 4) of the support shaft 222.

  The drive rod 224 transmits a driving force from the drive mechanism 200 to the link shaft 223, and one end portion (right end portion in FIG. 2) is connected to the drive mechanism 200 (diaphragm 232), and the other side. The end (left end in FIG. 2 and right end in FIG. 4) is fixed to one end (upper end in FIG. 4) of the link shaft 223. The connection pin 225 is a pin that rotatably engages the link shaft 223 and the drive rod 224.

-Drive mechanism 200-
Next, the configuration of the drive mechanism 200 will be described with reference to FIG. The drive mechanism 200 opens and closes the wastegate valve 210 via the link mechanism 220 based on an instruction from the ECU 300. The drive mechanism 200 includes a negative pressure actuator 230, a shut-off valve 240, an electronic vacuum regulating valve. (Hereinafter also referred to as E-VRV) 250, a negative pressure source 260, and a negative pressure pipe 270.

  The negative pressure actuator 230 drives the drive rod 224 using a negative pressure supplied from a negative pressure source 260 via a negative pressure pipe 270 as a power source. The negative pressure actuator 230 includes an outer wall 231, a diaphragm 232, an atmospheric chamber 233, a negative pressure. A chamber 234 and a coil spring 235 are provided.

  In the negative pressure actuator 230, the inside of the outer wall 231 is partitioned into an atmospheric chamber 233 and a negative pressure chamber 234 by a diaphragm 232. The negative pressure chamber 234 communicates with the negative pressure source 260 via the cutoff valve 240 and the E-VRV 250 when the cutoff valve 240 is open. The negative pressure chamber 234 includes a coil spring 235, and the coil spring 235 applies a biasing force that biases the diaphragm 232 to the atmosphere chamber 233 with respect to the diaphragm 232. Further, a drive rod 224 that can be moved forward and backward with the deformation of the diaphragm 232 is attached to the diaphragm 232.

  The shutoff valve 240 is interposed between the negative pressure actuator 230 and the E-VRV 250 and is a valve that opens and closes the negative pressure pipe 270 based on an instruction from the ECU 300. The shutoff valve 240 is composed of, for example, a VSV (vacuum switching valve).

  The E-VRV 250 is a valve that is interposed between the shutoff valve 240 and the negative pressure source 260 and controls the pressure in the negative pressure pipe 272 based on an instruction from the ECU 300. In addition, the E-VRV 250 includes an output port 251 connected to the negative pressure pipe 272, a negative pressure port 253 connected to the negative pressure source 260, and an atmospheric port 252 for introducing atmospheric air through a filter (not shown). Prepare. When a predetermined duty ratio signal is input from the ECU 300 to the E-VRV 250, the E-VRV 250 adjusts the inside of the negative pressure pipe 272 to a negative pressure having a magnitude corresponding to the duty ratio.

  The negative pressure source 260 includes, for example, a vacuum pump driven by the engine 1 and generates negative pressure that drives the negative pressure actuator 230. The negative pressure pipe 270 is a pipe that guides the negative pressure generated by the negative pressure source 260 to the negative pressure actuator 230, and includes a negative pressure pipe 271 between the negative pressure actuator 230 and the cutoff valve 240, the cutoff valve 240, and the like. It is divided into a negative pressure pipe 272 between the E-VRV 250 and a negative pressure pipe 273 between the E-VRV 250 and the negative pressure source 260.

  With such a configuration, when the shutoff valve 240 is in an open state and the electromagnetic solenoid of the E-VRV 250 is in a non-excited state, the negative pressure pipe 272 and the air inlet are in a conductive state, and the negative pressure The negative pressure chamber 234 of the actuator 230 is at atmospheric pressure. In this case, the drive rod 224 connected to the negative pressure actuator 230 (diaphragm 232) is most advanced by the urging force of the coil spring 235 (in FIG. 2, the most moved state to the left side, that is, the wastegate valve). 210 is held open.

  On the other hand, when the shutoff valve 240 is in an open state and the electromagnetic solenoid of the E-VRV 250 is in an excited state, the negative pressure pipes 271 and 272 are in a conductive state, and the inside of the negative pressure chamber 234 of the negative pressure actuator 230 is inside. Negative pressure. In this case, the drive rod 224 connected to the negative pressure actuator 230 (diaphragm 232) is displaced against the urging force of the coil spring 235, and the drive rod 224 is most retracted accordingly (right side in FIG. 2). The wastegate valve 210 is held in the most moved state, that is, the wastegate valve 210 is closed.

  Further, the forward / backward movement amount of the drive rod 224 connected to the negative pressure actuator 230 (diaphragm 232) can be adjusted by duty control of excitation and non-excitation of the electromagnetic solenoid of the E-VRV 250. By such a forward / backward movement of the drive rod 224 connected to the negative pressure actuator 230 (diaphragm 232), the link mechanism 220 is driven and the opening degree of the wastegate valve 210 is adjusted.

-ECU300-
Next, the configuration of the ECU 300 will be described with reference to FIGS. 1 and 5. The ECU 300 includes a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and a backup RAM.

  The ROM stores various control programs and table data that is referred to when the various control programs are executed. The CPU performs various processes by reading and executing various control programs stored in the ROM. The RAM is a memory that temporarily stores data input from each sensor as a result of processing by the CPU, and the backup RAM is a nonvolatile memory that stores data to be saved when the engine 1 is stopped, for example. Sex memory.

  The ECU 300 includes an engine speed sensor 31, a throttle opening sensor 32, an accelerator opening sensor 33 that detects an accelerator pedal depression amount (accelerator opening), a vehicle speed sensor 34 that detects a vehicle speed, and a brake pedal depression amount. Various sensors for acquiring various information indicating the driving state, such as a brake pedal sensor 35 for detecting the above, are connected.

  The output portion of the ECU 300 includes an injector (not shown) of the engine 1, the throttle valve 7, the EGR valve 124, the switching control valve 123, and the E-VRV 250 of the drive mechanism 200 of the wastegate valve device shown in FIG. A shutoff valve 240 or the like is connected.

  The ECU 300 controls the drive of the injector (fuel injection valve) (fuel injection control), the drive control of the throttle motor of the throttle valve 7 (intake air amount control), and EGR based on the detection signals of the various sensors. Various control of the engine including control of the amount (control of the EGR valve 124 and the switching control valve 123, etc.) is executed.

  Further, the CPU functionally functions as the valve opening degree control unit 310, the shut-off valve control unit 320, and the start / stop control unit 330 by reading and executing the control program stored in the ROM.

  The valve opening degree control unit 310 is a functional unit that controls the opening degree of the waste gate valve 210 via the E-VRV 250. Here, the valve opening degree control unit 310 uses, for example, the engine speed and the required torque as parameters, and a full supercharging region (valve fully closed region), a supercharging pressure adjusting region (valve opening adjusting region), and a supercharging region. Using the table (or map) in which three areas of no supply (valve full open area) are set, based on the required torque and the current engine speed, which of the above three areas is the operating area Is determined, and the opening degree of the wastegate valve 210 is instructed to the E-VRV 250.

  When it is determined that the operation region is in the full supercharging region (valve fully closed region), the valve opening degree control unit 310 fully closes the wastegate valve 210 with respect to the E-VRV 250. (Instruction for energizing the electromagnetic solenoid of the E-VRV 250) is output.

  On the other hand, when it is determined that the operation region is in the supercharging pressure adjustment region (valve opening adjustment region), the valve opening control unit 310 causes the wastegate valve 210 to be connected to the E-VRV 250, Instruction to achieve target opening, which is the opening to achieve supercharging pressure according to engine speed and required torque (duty control of excitation and de-excitation of electromagnetic solenoid of E-VRV250 according to target opening Output).

  Further, when it is determined that the operation region is in the non-supercharging region (valve full open region), the valve opening degree control unit 310 opens the waste gate valve 210 to the E-VRV 250. (Instruction to de-energize the electromagnetic solenoid of E-VRV 250) is output.

  The shut-off valve control unit 320 is a functional unit that controls opening and closing of the shut-off valve 240. Here, the shut-off valve control unit 320 corresponds to a shut-off valve control unit. Specifically, the shut-off valve control unit 320 closes the shut-off valve 240 when an idling stop condition for stopping idling of the engine 1 is satisfied. Note that the stop unit 331 determines whether or not the idling stop condition is satisfied.

  When the idling stop condition is established in this way, the shutoff valve 240 is closed by the shutoff valve control unit 320, and therefore, the shutoff valve 240 is between the establishment of the idling stop condition and the stop of the engine 1. Is closed, and negative pressure is maintained between the shut-off valve 240 and the negative pressure actuator 230 (in the negative pressure chamber 234 and the negative pressure pipe 271). For example, when restarting after idling is stopped, a negative pressure that is a driving source of the negative pressure actuator 230 is held between the shutoff valve 240 and the negative pressure actuator 230, so The gate valve 210 can be opened and closed in a short time. Therefore, since the wastegate valve 210 can be closed when restarting after idling is stopped, generation of turbo lag can be suppressed.

  In the present embodiment, the case where the shutoff valve control unit 320 closes the shutoff valve 240 when the idling stop condition is satisfied has been described. However, when the shutoff valve control unit 320 fulfills the stop condition of the engine 1. The shut valve 240 may be closed. In this case, after the ignition 1 is turned off and the engine 1 is stopped, when the ignition 1 is turned on and the engine 1 is started, the gap between the shut-off valve 240 and the negative pressure actuator 230 (negative pressure chamber 234 and In the negative pressure pipe 271), a negative pressure that is a driving source of the negative pressure actuator 230 is held, so that the waste gate valve 210 can be opened and closed by the negative pressure actuator 230 in a short period of time. Therefore, since the wastegate valve 210 can be closed when restarting after the engine is stopped, generation of turbo lag can be suppressed.

  Further, after the engine 1 is restarted, the shut-off valve control unit 320 opens the shut-off valve 240 when the opening condition that the negative pressure of the negative pressure source 260 can be secured is satisfied. Specifically, the opening condition is, for example, a condition that a predetermined time threshold TH or more has elapsed since the time when the engine 1 was restarted. The value of the time threshold value TH is, for example, that the pressure on the negative pressure source 260 side of the shutoff valve 240 (pressure in the negative pressure pipe 273) is the negative pressure actuator of the shutoff valve 240 from the time when the engine 1 is restarted. This is the period up to the time when the pressure becomes 230 (pressure in the negative pressure pipe 271) or less.

  Thus, after the engine 1 is restarted, the shutoff valve 240 is opened by the shutoff valve control unit 320 when the opening condition that the negative pressure of the negative pressure source 260 can be secured is satisfied. The shut-off valve 240 can be opened at an appropriate timing.

  That is, when the shutoff valve 240 is opened before the negative pressure of the negative pressure source 260 can be secured, the negative pressure source 260 can secure the negative pressure after the shutoff valve 240 is opened. In the period up to, the negative pressure held between the shutoff valve 240 and the negative pressure actuator 230 (in the negative pressure chamber 234 and the negative pressure pipe 271) is released, so that turbo lag occurs. On the other hand, when the shutoff valve 240 is opened after the negative pressure source 260 can secure the negative pressure, the negative pressure source 260 can ensure the negative pressure. Since the negative pressure held between the shutoff valve 240 and the negative pressure actuator 230 is released, the force for closing the shutoff valve 240 is weakened.

  In addition, since the opening condition is a condition that a predetermined time threshold value TH has elapsed from the time when the engine 1 is restarted, the cutoff valve 240 is appropriately set by setting the time threshold value TH appropriately. It can be opened at the timing.

  For example, from the time when the engine 1 is restarted, the pressure on the negative pressure source 260 side (in the negative pressure pipe 273) of the cutoff valve 240 is changed to the pressure on the negative pressure actuator 230 side (in the negative pressure pipe 271) of the cutoff valve 240. The time T0 required to agree with the above may be obtained by experiments or the like, and this time T0 may be set as the time threshold value TH. In this case, when the time threshold TH elapses from when the engine 1 is restarted, the pressure on the negative pressure source 260 side (in the negative pressure pipe 273) of the cutoff valve 240 is changed to the negative pressure of the cutoff valve 240. This is the same as the pressure on the actuator 230 (inside the negative pressure pipe 271). This timing is the earliest timing at which the negative pressure actuator 230 can be opened and closed by the negative pressure source 260. Therefore, since the shutoff valve 240 is opened at this timing, the shutoff valve 240 can be opened at an appropriate timing.

  In the present embodiment, the case where the opening condition is a condition that the negative pressure of the negative pressure source 260 can be secured will be described. However, the opening condition may be other conditions set in advance. For example, as shown in FIG. 2, a pressure sensor 241 that detects a pressure P1 on the negative pressure actuator 230 (inside the negative pressure pipe 271) side of the shutoff valve 240, and a negative pressure source 260 side (negative pressure pipe) of the shutoff valve 240 273), and the open condition may be a condition that the pressure P2 is equal to or lower than the pressure P1. In this case, the shutoff valve 240 can be opened at a more appropriate timing.

  The start / stop control unit 330 stops idling of the engine 1 and restarts the engine 1 after being stopped, and functionally includes a stop unit 331 and a restart unit 332.

  When the idling stop condition set in advance is satisfied, the stop unit 331 outputs information indicating that the idling stop condition is satisfied to the shutoff valve control unit 320 and stops idling of the engine 1 (fuel supply) It is a functional part to be stopped). Here, the idling stop condition is, for example, when the ignition is “ON”, the vehicle speed sensor 34 detects that the vehicle speed is “0”, and the brake pedal sensor 35 depresses the brake pedal. It is a condition that it has been detected.

  The restart unit 332 restarts the engine 1 and shuts off the valve when the idling of the engine 1 is stopped (fuel supply is stopped) by the stop unit 331 and a preset restart condition is satisfied. This is a functional unit that outputs information indicating that the engine 1 has been restarted to the unit 320. Here, the restart condition is, for example, that the brake pedal sensor 35 detects that the brake pedal depressing operation has been performed while the idling of the engine 1 is stopped (fuel supply stopped) by the stop unit 331. Or the accelerator opening sensor 33 detects that the accelerator pedal has been depressed.

-Opening / closing operation of shutoff valve 240-
Next, the opening / closing operation of the shutoff valve 240 performed by the shutoff valve control unit 320 of the ECU 300 will be described. FIG. 6 is a flowchart showing an example of the operation of the shut-off valve control unit 320 shown in FIG. Note that the following operation is performed by the shut-off valve control unit 320 unless otherwise specified. Further, here, for convenience, a case will be described in which the engine 1 is idling in the initial state.

  First, in step S101, it is determined whether a preset idling stop condition is satisfied. Specifically, whether the idling stop condition set in advance is satisfied is determined by the stop unit 331, and when it is determined that the idling stop condition is satisfied, the stop unit 331 to the shut-off valve control unit 320 In response to this, information indicating that the idling stop condition is satisfied is output. That is, the shutoff valve control unit 320 determines whether or not the idling stop condition is satisfied based on whether or not information indicating that the idling stop condition is satisfied is input from the stop unit 331. If YES in step S101, the process proceeds to step S103. If NO in step S101, the process is in a standby state.

  In step S103, the shutoff valve 240 is closed. By closing the shut-off valve 240, negative pressure is maintained between the shut-off valve 240 and the negative pressure actuator 230 (in the negative pressure chamber 234 and the negative pressure pipe 271).

  In step S105, the restart unit 332 determines whether a preset restart condition is satisfied. If YES in step S105, the process proceeds to step S107. If NO in step S105, the process is in a standby state.

  In step S <b> 107, the restart unit 332 restarts the engine 1 and outputs information indicating that the engine 1 has been restarted to the shut-off valve control unit 320. Then, the process proceeds to step S109.

  In step S109, it is determined whether or not a preset time threshold value TH has elapsed since the engine 1 was restarted (whether or not the “open condition” is satisfied). If YES in step S109, the process proceeds to step S111. If NO in step S109, the process is in a standby state.

  In step S111, the shutoff valve 240 is opened, and the process is returned to step S101. When the shutoff valve 240 is opened, the opening control of the wastegate valve 210 is executed by the E-VRV 250 via the negative pressure actuator 230 based on an instruction from the valve opening control unit 310. .

  In this way, since the shutoff valve 240 is opened and closed at an appropriate timing by the shutoff valve control unit 320, the occurrence of turbo lag can be suppressed.

-Other embodiments-
In the present embodiment, the case where the valve opening degree control unit 310, the shut-off valve control unit 320, the stop unit 331, and the restart unit 332 are configured as functional units of the ECU 300 has been described. At least one of the shut-off valve control unit 320, the stop unit 331, and the restart unit 332 may be configured by hardware such as an electronic circuit.

  In the present embodiment, the case where the internal combustion engine is the diesel engine 1 has been described. However, another type of internal combustion engine (for example, a gasoline engine or the like) may be used.

  In this embodiment, the case where the negative pressure actuator is the diaphragm type negative pressure actuator 230 has been described. However, the negative pressure actuator is another type of negative pressure actuator (for example, a piston type negative pressure actuator). Form may be sufficient.

  The present invention can be used for an open / close control device for a wastegate valve mounted on a vehicle.

DESCRIPTION OF SYMBOLS 1 Engine 100 Turbocharger 101 Turbine wheel 110 Turbine housing 110a Exhaust gas outlet passage 111 Exhaust gas bypass passage 111a Waste gate hole 112 Valve seat 200 Drive mechanism 210 Waste gate valve 220 Link mechanism 230 Negative pressure actuator 240 Shut-off valve 250 Electronic vacuum regulation Rating valve (E-VRV)
260 Negative pressure source 270 (271, 272, 273) Negative pressure pipe 300 ECU
310 Valve opening control unit 320 Shut-off valve control unit (shut-off valve control means)
330 Start / Stop Control Unit 331 Stop Unit 332 Restart Unit

Claims (6)

An opening / closing control device for a wastegate valve disposed in a bypass passage that bypasses a turbine wheel,
A negative pressure actuator for opening and closing the waste gate valve;
A negative pressure source driven by an internal combustion engine;
A shutoff valve interposed between the negative pressure actuator and the negative pressure source;
A shut-off valve control means for controlling opening and closing of the shut-off valve,
The wastegate valve opening / closing control device, wherein the shutoff valve control means closes the shutoff valve when a stop condition of the internal combustion engine is satisfied. In the opening / closing control device of the wastegate valve according to claim 1,
The waste gate valve opening / closing control device, wherein the internal combustion engine stop condition is an idling stop condition for stopping idling of the internal combustion engine. In the opening / closing control device of the waste gate valve according to claim 2,
The shutoff valve control means opens and shuts off the shutoff valve when a preset opening condition is satisfied after the internal combustion engine is restarted. In the opening / closing control device of the wastegate valve according to claim 3,
The opening / closing control device for a wastegate valve, wherein the opening condition is a condition that a negative pressure of the negative pressure source can be secured. In the opening / closing control device of the wastegate valve according to claim 4,
The opening / closing control apparatus for a wastegate valve, wherein the opening condition is a condition that a predetermined time threshold or more has elapsed from a time when the internal combustion engine is restarted. In the opening / closing control device of the wastegate valve according to claim 4,
The opening control device for a wastegate valve, wherein the opening condition is a condition that a pressure on the negative pressure source side of the shutoff valve is equal to or lower than a pressure on the negative pressure actuator side of the shutoff valve.

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