JP2019074017A - Control device of waste gate valve - Google Patents

Abstract

To provide a control device of a waste gate valve which can eliminate an adhesion state of the waste gate valve in an early stage.SOLUTION: An ECU controls a waste gate valve so as to be closed up to an opening by which prescribed target intake pressure can be obtained at a start of an engine (step S3). When an intake pressure difference between target intake pressure and actual intake pressure is not smaller than a prescribed intake pressure difference after the waste gate valve is controlled so as to be closed up to the opening by which the target intake pressure can be obtained (YES in step S4), the ECU controls the waste gate valve to a valve-opening side once, and after that, controls the waste gate valve so as to reach the opening by which the target intake pressure can be obtained once again (step S5). It is preferable that the ECU close the waste gate valve up to the opening by which the target intake pressure can be obtained after repeating the opening and closing of the waste gate valve a plurality of times at prescribed intervals.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a waste gate valve control device.

  Some engines mounted on vehicles such as automobiles include a turbocharger that supercharges intake air using exhaust gas. The turbocharger has a turbine that is rotated by the exhaust gas, and a compressor that supercharges intake air by integrally rotating with the turbine.

  Further, the turbocharger is provided with a bypass passage so that the exhaust gas bypasses the turbine, and the bypass pressure is adjusted by opening and closing the bypass passage with a waste gate valve.

  In a turbocharger provided with a waste gate valve, if the waste gate valve is stuck due to freezing or the like, the opening and closing of the waste gate valve will be hindered, and the supercharging pressure can not be properly adjusted.

  DESCRIPTION OF RELATED ART Conventionally, what was described in patent document 1 as a technique which performs fault diagnosis of a waste gate valve is known. According to Patent Document 1, when the ignition timing is not retarded from the first ignition timing, the waste gate valve is set to be closed, and when the ignition timing is set to the first ignition timing, The opening degree of the waste gate valve is controlled so that the rotation speed of the internal combustion engine is maintained at the target rotation speed.

  Further, in the case described in Patent Document 1, when the opening degree of the waste gate valve is controlled, the time when the rotational speed of the internal combustion engine exceeds the target rotational speed becomes equal to or longer than the second predetermined time. Has diagnosed that the waste gate valve has failed.

  Thereby, the thing of patent document 1 can suppress the deterioration of the emission which arises at the time of a catalyst not warming up, and can perform failure diagnosis of a waste gate valve efficiently.

JP, 2006-348757, A

  Here, in the control method in which the waste gate valve of the turbocharger is controlled by the actuator, the waste gate valve is left open without performing control in a normal state where supercharging is unnecessary, and supercharging is necessary. In the situation, there is normally open control in which the waste gate valve is controlled to the closing side by using a negative pressure or the like.

  The waste gate valve in which the normally open control is performed is held in the open state without performing control since supercharging is not necessary at the time of starting the engine. On the other hand, when the waste gate valve is stuck when the engine is stopped, it is preferable to eliminate the stuck state at the time of starting the engine.

  However, according to the technology described in Patent Document 1, when the waste gate valve is normally open-controlled, no control is performed on the waste gate valve at the time of engine start, and the waste gate valve is kept open. Therefore, it can not be diagnosed whether or not the waste gate valve is broken. For this reason, the thing of patent document 1 had the problem that the adhering state of a waste gate valve could not be eliminated early.

  Then, an object of this invention is to provide the control apparatus of the waste gate valve which can eliminate the adhering state of a waste gate valve early.

  One aspect of the invention of a control device of a waste gate valve that solves the above-mentioned problems compresses the intake air of the engine by transmitting an engine, a turbine that rotates by passing the exhaust gas of the engine, and the rotation of the turbine. A turbocharger having a compressor, a bypass passage provided so that the exhaust gas bypasses the turbine, and a wastegate provided in the bypass passage to adjust the inflow of the exhaust gas to the bypass passage The waste gate valve is mounted on a vehicle that is a normally open waste gate valve that is opened when the engine is started, and has a control unit that adjusts the opening degree of the waste gate valve. A control device for a waste gate valve, wherein the control unit At the start of the engine, and controls to close the waste gate valve to opening to obtain a predetermined target intake pressure.

  Thus, according to the present invention, the stuck state of the waste gate valve can be eliminated early.

FIG. 1 is a block diagram of a vehicle equipped with a control device for a waste gate valve according to an embodiment of the present invention. FIG. 2 is a flow chart for explaining the operation of the control device of the waste gate valve according to the embodiment of the present invention. FIG. 3 is a view for explaining the correlation between the control duty of the waste gate valve according to an embodiment of the present invention and the actuator negative pressure.

  A control device for a waste gate valve according to an embodiment of the present invention includes an engine, a turbine that rotates by passing an exhaust gas of the engine, and a turbo that has a compressor that compresses engine intake by transmitting rotation of the turbine. A waste gate valve comprising: a supercharger; a bypass passage provided so that exhaust gas bypasses the turbine; and a waste gate valve provided in the bypass passage for adjusting the inflow amount of the exhaust gas to the bypass passage, A control device for a waste gate valve mounted on a vehicle that is a normally open waste gate valve that is opened at the start of the engine and having a control unit that adjusts the opening degree of the waste gate valve, the control unit When the engine is started, the And controlling so as to close the gate valve. Thus, the control device for the waste gate valve according to the embodiment of the present invention can quickly eliminate the stuck state of the waste gate valve.

  Hereinafter, a control device for a waste gate valve according to an embodiment of the present invention will be described in detail with reference to the drawings.

  In FIG. 1, a vehicle 1 equipped with a waste gate valve control device according to an embodiment of the present invention is configured to include an engine 2 and an ECU (Electronic Control Unit) 3 as a control unit.

  The engine 2 is constituted by a four-stroke engine performing a series of four strokes consisting of an intake stroke, a compression stroke, an expansion stroke and an exhaust stroke while the piston reciprocates twice in the cylinder.

  The piston housed in each cylinder is connected to the crankshaft via a connecting rod. The connecting rod is adapted to convert the reciprocating movement of the piston into rotational movement of the crankshaft.

  Therefore, the engine 2 reciprocates the piston by burning a mixture of fuel and air in the combustion chamber 25 in the cylinder, and drives the vehicle 1 by rotating the crankshaft through the connecting rod. It is designed to generate power.

  An intake manifold 31 for introducing air into the combustion chamber 25 is provided at an intake port of the engine 2. The intake manifold 31 is connected to an intake pipe 32 for sucking in the outside air. That is, the intake manifold 31 communicates the intake pipe 32 with the intake port of each cylinder.

  An intake pressure sensor 27 is provided upstream of the intake manifold 31. The upstream portion of the intake manifold 31 forms a surge tank that temporarily stores air.

  The intake pressure sensor 27 detects the pressure of the intake manifold 31 as a manifold pressure, and transmits a detection signal to the ECU 3. The manifold pressure is a pressure on the downstream side of the throttle valve 33 in the intake pipe 32, and changes according to the opening degree of the throttle valve 33, the engine speed, and the like.

  An air cleaner 34 and a throttle valve 33 are provided in the intake pipe 32 from the upstream side to the downstream side in the intake direction, where the passage direction of the fresh air in the intake pipe 32 is the intake direction. The air cleaner filters the intake air.

  The throttle valve 33 is configured as an electronically controlled throttle valve, and adjusts the intake air amount of the engine 2 by controlling the throttle opening degree in accordance with a command signal from the ECU 3.

  A throttle opening degree sensor 28 is provided in the throttle valve 33. The throttle opening degree sensor 28 detects the opening degree of the throttle valve 33, and transmits a detection signal to the ECU 3 as the throttle opening degree.

  An air flow sensor 21 is provided on the upstream side of the throttle valve 33 in the intake direction, where the passage direction of the fresh air in the intake pipe 32 is the intake direction. The air flow sensor 21 detects the flow rate of air flowing into the engine 2.

  At an exhaust port of the engine 2, an exhaust manifold 41 for exhausting the exhaust gas generated by the combustion of the air-fuel mixture in the combustion chamber 25 to the outside of the vehicle is provided. The exhaust manifold 41 is connected to the exhaust pipe 42. That is, the exhaust manifold 41 communicates the exhaust pipe 42 with the exhaust port of each cylinder.

  The exhaust pipe 42 is provided with a three-way catalyst 43 and oxygen sensors 44 and 45 with a heater. The three-way catalyst 43 purifies exhaust gas discharged from the combustion chamber 25 of the engine 2, that is, burned gas.

  Here, when the direction in which the exhaust gas is discharged is the exhaust direction, the oxygen sensor 44 is provided upstream of the three-way catalyst 43 in the exhaust direction. In addition, the oxygen sensor 45 is provided downstream of the three-way catalyst 43 in the exhaust direction.

  The oxygen sensors 44, 45 detect whether the air-fuel ratio is rich or lean with respect to the stoichiometric air-fuel ratio by detecting the concentration of oxygen contained in the exhaust gas, and transmit a detection signal to the ECU 3 Do.

  The oxygen sensors 44 and 45 have output characteristics in which the output suddenly changes when the air-fuel ratio is rich and lean with the theoretical air-fuel ratio, or have linear output characteristics with respect to the oxygen concentration It consists of a sensor.

  The fuel tank 51 stores gasoline as fuel of the engine 2 under normal pressure. The gasoline stored in the fuel tank 51 is pressure-fed by the fuel pump 51A, further pressurized by the high-pressure fuel pump 55, and injected from the injector 24 into the combustion chamber 25 of each cylinder.

  The engine 2 includes a variable valve timing mechanism 26 that changes the open / close timing (hereinafter referred to as a valve timing) of the intake valve, and a VVT oil control valve 71 that operates the variable valve timing mechanism 26 hydraulically.

  The VVT oil control valve 71 is electrically controlled by the ECU 3. The ECU 3 controls the variable valve timing mechanism 26 via the variable valve timing mechanism 26 to change the valve timing.

  The variable valve timing mechanism 26 may be provided on both the intake side and the exhaust side. In this case, by controlling the variable valve timing mechanism 26 by the ECU 3, both the valve timing and the valve side of the intake side and the exhaust side can be controlled. The amount of overlap can be adjusted.

  The fuel tank 51 is connected to a canister 52 for adsorbing the fuel vapor. The purge pipe 53 is connected to the canister 52, and the intake manifold 31 is connected to the end of the purge pipe 53 opposite to the end where the canister 52 is connected. The evaporated fuel adsorbed in the canister 52 is introduced into the intake manifold 31 via the purge pipe 53 together with air as a purge gas.

  The purge pipe 54 is provided with a purge valve 54. The purge valve 54 is a vacuum switching valve operated by a negative pressure, and the ECU 3 controls opening and closing. The ECU 3 controls the amount of purge gas introduced into the intake manifold 31 by controlling the opening and closing of the purge valve 54.

  The engine 2 includes a turbocharger 60 that pressurizes intake air using exhaust gas, a bypass passage 46 through which exhaust gas bypassing the turbine 60A of the turbocharger 60 passes, and exhaust gas passing through the bypass passage 46 A waste gate valve 65 is provided to adjust the amount of gas.

  The turbocharger 60 includes a turbine 60A disposed in the exhaust pipe 42 and a compressor 60B disposed in the intake pipe 32, and when the turbine 60A is rotated by the exhaust gas, this rotation is transmitted to the compressor 60B, and the compressor 60B supercharges intake.

  Thus, a turbocharger 60 having a compressor 60B that compresses the intake of the engine 2 by transmitting the rotation of the turbine 60A and the turbine 60A that are rotated by passing the exhaust gas of the engine 2 to the vehicle 1; A bypass passage 46 is provided so that the exhaust gas bypasses the turbine 60A, and a waste gate valve 65 provided in the bypass passage 46 for adjusting the inflow amount of the exhaust gas to the bypass passage 46.

  An intercooler 35 is provided downstream of the compressor 60B in the intake pipe 32, and the intercooler 35 cools the intake air, which is heated when supercharged by the compressor 60B, by heat exchange with the outside air.

  A waste gate valve actuator 69 is connected to the waste gate valve 65. A vacuum pump 67 that generates a negative pressure is connected to the waste gate valve actuator 69 via a negative pressure pipe 68. A vacuum switching valve 66 is provided in the middle of the negative pressure pipe 68, and the vacuum switching valve 66 is controlled by the ECU 3.

  The waste gate valve actuator 69 comprises a rod 70, a diaphragm 69A and a spring 69B. The distal end of the rod 70 is connected to the waste gate valve 65, and the proximal end of the rod 70 is connected to the diaphragm 69A. The restoring force of the spring 69 B acts to open the waste gate valve 65 via the rod 70.

  The vacuum pump 67 uses the rotation of the camshaft of the engine 2 to generate a negative pressure. The vacuum switching valve 66 is duty-controlled by the ECU 3 to be controlled to an opening degree between fully closed and fully open. The vacuum pump 67 supplies the negative pressure corresponding to the opening degree from the vacuum pump 67 to the waste gate valve actuator 69.

  When the vacuum switching valve 66 is closed, no negative pressure is supplied to the waste gate valve actuator 69, and the waste gate valve 65 is opened by the restoring force of the spring.

  When the vacuum switching valve 66 is opened under the control of the ECU 3, the negative pressure of the vacuum pump 67 is supplied to the waste gate valve actuator 69 through the negative pressure pipe 68. Then, in the waste gate valve actuator 69, the diaphragm 69A moves against the restoring force of the spring by the negative pressure, and closes the waste gate valve 65 via the rod 70.

  The intake pipe 32 is provided with a bypass passage 36 which diverts the intake air from the downstream side to the upstream side of the compressor 60B of the turbocharger 60. An air bypass valve 38 is provided in the middle of the bypass passage 36.

  The air bypass valve 38 is opened and closed by a vacuum switching valve 37. The ECU 3 adjusts the opening degree of the air bypass valve 38 by operating the vacuum switching valve 37 under duty control.

  When the throttle valve 33 is suddenly closed, the ECU 3 operates the vacuum switching valve 37 to open the air bypass valve 38. Thereby, the supercharging pressure on the downstream side of the compressor 60B can be released to the upstream side, the bounce of the air flow can be suppressed, and the back turbine noise and the damage to the turbocharger 60 can be reduced.

  The ECU 3 is configured by a computer unit provided with a central processing unit (CPU), a random access memory (RAM), a read only memory (ROM), a flash memory, an input port, and an output port.

  A program for causing the computer unit to function as the ECU 3 is stored in the ROM of the ECU 3 together with various control constants, various maps, and the like. That is, when the CPU executes a program stored in the ROM, the computer unit functions as the ECU 3.

  In addition to the above-described airflow sensor 21 and oxygen sensors 44 and 45, the input port of the ECU 3 includes an accelerator opening sensor 22, a crank angle sensor 23, a cam angle sensor 72, a coolant temperature sensor 73, and a throttle upstream side intake pressure sensor 75 Etc. are connected.

  The accelerator opening degree sensor 22 detects an accelerator opening degree representing the depression amount of the accelerator pedal 22A, and transmits a detection signal to the ECU 3.

  The crank angle sensor 23 detects a rotation angle of a crankshaft of the engine 2. The ECU 3 calculates the engine speed of the engine 2 based on the detection result input from the crank angle sensor 23.

  The cam angle sensor 72 detects the rotation angle of the camshaft of the engine 2. The ECU 3 determines the cylinder based on the detection result input from the cam angle sensor 72.

  The coolant temperature sensor 73 detects the temperature of the coolant flowing through the engine 2 and transmits a detection signal to the ECU 3. The throttle upstream side intake pressure sensor 75 detects an intake pressure on the upstream side of the throttle valve 33 in the intake pipe 32 and transmits a detection signal to the ECU 3. The throttle upstream side intake pressure sensor 75 constitutes an intake pressure sensor in the present invention.

  Various devices such as an injector 24, a throttle valve 33, a purge valve 54, a VVT oil control valve 71, and a vacuum switching valve 66 are connected to the output port of the ECU 3.

  The ECU 3 controls the operating state of the engine 2 by controlling the injectors 24, the throttle valve 33, the purge valve 54, the VVT oil control valve 71, and the like. Further, the ECU 3 controls the vacuum switching valve 66 to adjust the opening degree of the waste gate valve 65.

  Here, the control method of the waste gate valve 65 includes normal close control and normal open control. The normal close control is control to close the waste gate valve 65 and perform supercharging normally, and to open the waste gate valve 65 when the manifold pressure becomes higher than a predetermined allowable pressure.

  On the other hand, normally open control is control that normally opens the waste gate valve 65 and closes the waste gate valve when supercharging needs to be performed according to an increase in the accelerator opening degree of the accelerator pedal 22A, etc. .

  The waste gate valve 65 of this embodiment is a normally open waste gate valve. Here, the normal time refers to an operating state that does not require a large boost pressure, and includes, for example, a steady running state, a decelerating running state, and an engine start time. The normally open waste gate valve is opened at least when the engine is started.

  Here, in the turbocharger 60 provided with the waste gate valve 65, when the waste gate valve 65 is stuck due to icing or the like when the engine 2 is stopped for a long time in an environment where the outside temperature is low, etc., the waste gate valve It may interfere with the opening and closing of the 65.

  The sticking of the waste gate valve 65 is caused not only by the sticking of the waste gate valve 65 itself but also by the sticking of the diaphragm 69A in the waste gate valve actuator 69.

  Therefore, when the waste gate valve 65 is stuck due to the icing in the diaphragm 69A, if the heat conductivity from the waste gate valve 65 to the diaphragm 69A is small, the sticking is eliminated or prevented by the heat of the exhaust gas. Can not expect to be done. In addition, the waste gate valve 65 may stick due to clogging of foreign matter instead of freezing, etc. In this case, the sticking can not be canceled by the heat of the exhaust gas.

  Therefore, in order to eliminate the sticking, it is effective to actually operate the waste gate valve 65 so as to destroy the frozen ice and foreign matter.

  Therefore, in the present embodiment, when the engine 2 is started, the ECU 3 controls the waste gate valve 65 to close to an opening degree for obtaining a predetermined target intake pressure.

  In addition, after the ECU 3 controls the waste gate valve 65 to close to an opening degree for obtaining the target intake pressure, the waste gate valve 65 is operated if the intake pressure difference between the target intake pressure and the actual intake pressure is equal to or greater than the predetermined intake pressure difference. Is preferably controlled to the valve-opening side, and then controlled to the valve-closing side so as to obtain the opening degree for obtaining the target intake pressure again.

  Further, preferably, after opening and closing the waste gate valve 65 a plurality of times at predetermined intervals, the ECU 3 performs control so as to close the waste gate valve 65 to an opening degree for obtaining a target intake pressure.

  In addition, after the ECU 3 controls the waste gate valve 65 to close to an opening degree for obtaining the target intake pressure, the waste gate valve 65 is operated if the intake pressure difference between the target intake pressure and the actual intake pressure is equal to or greater than a predetermined intake pressure difference Is preferably opened and closed several times at predetermined intervals.

  In addition, it is preferable that the ECU 3 determine that the engine 2 is being started on condition that the start of the engine 2 is started and immediately after the engine 2 is completely detonated.

  The operation of the control apparatus for the waste gate valve according to the present embodiment configured as described above will be described with reference to the flowchart of FIG.

  In FIG. 2, the ECU 3 repeatedly determines whether the engine 2 has been started and is in an idle state (step S1). Here, the ECU 3 determines that the engine 2 is started on condition that the start of the engine 2 is started and the engine 2 is completely detonated.

  Further, the ECU 3 determines that the engine 2 is in the idle state on condition that the engine speed is a predetermined idle speed. Therefore, that the engine 2 is started and in the idle state means that the start of the engine 2 is started and the engine 2 is in a state of complete explosion.

  When the engine 2 is started in step S1 and in the idle state, the ECU 3 proceeds to step S2. In step S2, the ECU 3 determines whether any one of the engine water temperature, the engine oil temperature, the transmission oil temperature, and the outside air temperature is equal to or lower than a predetermined temperature (step S2).

  Here, the technical significance of comparing the engine water temperature, the engine oil temperature, the transmission oil temperature, and the outside air temperature with the predetermined temperature in step S2 is to determine whether the waste gate valve 65 may be stuck due to icing. is there. The case where any one of the engine water temperature, the engine oil temperature, the transmission oil temperature, and the outside air temperature is lower than or equal to a predetermined temperature means that the waste gate valve 65 is highly likely to be stuck by icing. In this step S2, the ECU 3 determines YES if any one of the engine water temperature, engine oil temperature, transmission oil temperature and outside air temperature is lower than a predetermined temperature, and any of the engine oil temperature, transmission oil temperature and outside air temperature When the temperature exceeds the predetermined temperature, it is determined as NO. The predetermined temperature may be a temperature common to the engine water temperature, the engine oil temperature, the transmission oil temperature or the outside temperature, and is set individually for each of the engine water temperature, the engine oil temperature, the transmission oil temperature or the outside temperature It may be a temperature.

  When the ECU 3 determines NO in step S2, the ECU 3 ends the current operation. On the other hand, when it is determined as YES in step S1, the ECU 3 proceeds to step S3.

  In step S3, the ECU 3 closes the waste gate valve 65 (denoted as WGV in the drawing) to a predetermined opening degree. The predetermined opening degree is an opening degree for obtaining a predetermined target boost pressure.

  Next, in step S4, the ECU 3 determines whether or not there is a difference between the target supercharging pressure and the actual supercharging pressure by a predetermined value or more. The actual supercharging pressure is an intake pressure on the upstream side of the throttle valve 33 in the intake pipe 32, which is actually measured by the throttle upstream side intake pressure sensor 75.

  If there is no difference between the target supercharging pressure and the actual supercharging pressure in step S4, the ECU 3 ends the current operation. On the other hand, when there is a difference between the target supercharging pressure and the actual supercharging pressure in step S4, the ECU 3 proceeds to step S5.

  In step S5, the ECU 3 executes waste gate valve sticking prevention control (described as WGV sticking prevention control in the drawing). Next, the ECU 3 once again returns the waste gate valve 65 to the fully open state, and then executes step S3 again.

  Thereafter, when there is a difference between the target supercharging pressure and the actual supercharging pressure in step S4, the ECU 3 executes waste gate valve sticking prevention control again in step S5. On the other hand, when it is determined in step S4 that there is no difference between the target supercharging pressure and the actual supercharging pressure, the present operation is ended.

  In the waste gate valve sticking prevention control in step S5, the ECU 3 once fully opens the waste gate valve 65, and then fully closes the waste gate valve 65.

  Here, in FIG. 3, the horizontal axis indicates the duty ratio of the vacuum switching valve 66, and the vertical axis indicates the actuator negative pressure. The actuator negative pressure is expressed such that the negative pressure becomes stronger and the absolute pressure becomes smaller toward the lower side in FIG.

  In the waste gate valve sticking prevention control, the ECU 3 controls the vacuum switching valve 66 to a duty ratio that is an opening degree for obtaining the target boost pressure described above to make the actuator negative pressure strong. That is, the absolute pressure is reduced.

  At this time, the duty ratio of the vacuum switching valve 66 is fully closed from the normal control range at idle, as described as WGV sticking prevention control in the figure, and the waste gate valve 65 is fully closed. It is the range of the duty ratio.

  The waste gate valve 65, which is fully open because the engine 2 is started, is fully closed by increasing the actuator negative pressure (reducing the absolute pressure) by waste gate valve sticking prevention control.

  Therefore, if the waste gate valve 65 is icing or the like, the waste gate valve 65 is fully closed several times until the target supercharging pressure is obtained due to the ice being destroyed by the icing, so that the sticking of the waste gate valve 65 It is eliminated.

  As described above, according to the present embodiment, when starting the engine 2, the ECU 3 controls the waste gate valve 65 to close to an opening degree for obtaining a predetermined target intake pressure.

  Thereby, when the engine 2 is started, the waste gate valve 65 is forcibly closed to an opening degree for obtaining the target boost pressure, and therefore, if the waste gate valve 65 or the waste gate valve actuator 69 is icing, It is possible to eliminate the sticking of the waste gate valve 65 due to these freezing. Therefore, the controllability of the waste gate valve 65 can be improved immediately after the start of the engine 2.

  Further, since the opening degree of the waste gate valve 65 is adjusted when the engine 2 is started, the stuck state of the waste gate valve 65 can be eliminated early, and controllability of the waste gate valve 65 is improved immediately after the engine 2 is started. be able to.

  As a result, the stuck state of the waste gate valve 65 can be eliminated early.

  Further, according to the present embodiment, after the ECU 3 controls the waste gate valve 65 to close to the opening degree for obtaining the target intake pressure, the intake pressure difference between the target intake pressure and the actual intake pressure is equal to or greater than the predetermined intake pressure difference. In some cases, the waste gate valve 65 is controlled to the valve opening side, and then is controlled to the valve closing side so as to obtain the opening degree for obtaining the target intake pressure again.

  Thereby, the waste gate valve 65 is controlled to the valve closing side until the opening degree at which the target intake pressure is obtained when the engine 2 is started, and the differential pressure between the target intake pressure and the actual intake pressure at that time is equal to or higher than a predetermined differential pressure. For example, after the waste gate valve 65 is once controlled to the valve opening side, it is controlled to the valve closing side again to the opening degree for obtaining the target intake pressure. As described above, when the target intake pressure can not be obtained, the waste gate valve 65 can be prevented from adhering by controlling the waste gate valve 65 to the valve opening side and then controlling it to the valve closing side again. .

  Further, according to the present embodiment, after opening and closing the waste gate valve 65 a plurality of times at predetermined intervals, the ECU 3 controls the waste gate valve 65 to close to an opening degree for obtaining the target intake pressure.

  Thereby, the stuck state of the waste gate valve 65 can be eliminated earlier.

  Further, according to the present embodiment, after the ECU 3 controls the waste gate valve 65 to close to the opening degree for obtaining the target intake pressure, the intake pressure difference between the target intake pressure and the actual intake pressure is equal to or greater than the predetermined intake pressure difference. In some cases, the waste gate valve 65 is opened and closed multiple times at predetermined intervals.

  Thereby, the stuck state of the waste gate valve 65 can be eliminated earlier.

  Further, according to the present embodiment, the ECU 3 determines that the engine 2 is about to be started under the condition that the start of the engine 2 is started and the engine 2 is in the complete explosion state immediately after.

  As a result, the intake amount of the engine 2 is stable immediately after the engine 2 is completely detonated, and sticking of the waste gate valve 65 when the waste gate valve 65 is closed to obtain the target intake pressure. Can be determined with high accuracy.

  While embodiments of the present invention have been disclosed, it will be apparent to those skilled in the art that changes may be made without departing from the scope of the present invention. All such modifications and equivalents are intended to be included in the following claims.

2 Engine 3 ECU (control unit)
46 bypass passage 60 turbocharger 60A turbine 60B compressor 65 waste gate valve 75 throttle upstream intake pressure sensor (intake pressure sensor)

Claims (5)

With the engine,
A turbocharger having a turbine that rotates by passing the exhaust gas of the engine and a compressor that compresses the intake of the engine by transmitting rotation of the turbine;
A bypass passage provided for the exhaust gas to bypass the turbine;
And a waste gate valve provided in the bypass passage to adjust the inflow of the exhaust gas to the bypass passage,
The waste gate valve is mounted on a vehicle that is a normally open waste gate valve that is opened when the engine is started.
A control device for a waste gate valve including a control unit that adjusts the opening degree of the waste gate valve, the control device comprising:
The control unit
A control device for a waste gate valve, which is controlled to close the waste gate valve to an opening degree for obtaining a predetermined target intake pressure at the start of the engine. It has an intake pressure sensor that detects the intake pressure,
The control unit
When the intake pressure difference between the target intake pressure and the actual intake pressure is equal to or greater than a predetermined intake pressure difference after controlling the waste gate valve to close to an opening degree for obtaining the target intake pressure,
The control device for the waste gate valve according to claim 1, characterized in that the waste gate valve is controlled to the valve opening side and then to the valve closing side so as to obtain the target intake pressure again. . The control unit
The waste gate according to claim 1 or 2, wherein the waste gate valve is controlled to be closed to an opening degree for obtaining the target intake pressure after opening and closing the waste gate valve a plurality of times at predetermined intervals. Valve control device. The control unit
When the intake pressure difference between the target intake pressure and the actual intake pressure is equal to or greater than a predetermined intake pressure difference after controlling the waste gate valve to close to an opening degree for obtaining the target intake pressure,
The control device of the waste gate valve according to claim 2, wherein the waste gate valve is opened and closed plural times at predetermined intervals. The control unit
The waste gate valve according to claim 1, characterized in that it is determined that the engine is started, provided that the start of the engine is started and it is immediately after the engine is fully detonated. Control device.

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