JP3752018B2 - Exhaust resistance variable muffler operation confirmation device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention, ExhaustVariable exhaust resistance muffler with multiple exhaust modes with different air resistanceWorkThe present invention relates to an operation confirmation device for an exhaust resistance variable muffler capable of easily confirming movement.
[0002]
[Prior art]
In recent years, a primary turbocharger and a secondary turbocharger are arranged in parallel in the intake and exhaust systems of the engine, and the exhaust system has a variable exhaust resistance muffler with multiple exhaust modes with different exhaust resistances. In the region, both the control valves are fully opened to make a twin turbo state in which both the primary turbocharger and the secondary turbocharger are supercharged, and the exhaust resistance variable muffler valve is opened to exhaust resistance. By adopting an exhaust mode with less exhaust gas, both high engine output due to the twin turbo state with both turbochargers operating and a reduction in exhaust resistance in response to an increase in exhaust gas flow at this time can be achieved. In the low speed range, the intake control valve is closed and the exhaust control valve is closed or slightly opened (to pre-rotate the secondary turbocharger). When the exhaust gas flow rate is low, the primary turbocharger can be operated when the exhaust gas flow rate is low by closing the exhaust resistance variable muffler valve and setting it to the exhaust mode with a large exhaust resistance. The exhaust gas is intensively supplied to the machine to increase the flow rate of the exhaust gas flow flowing through the turbine of the primary turbocharger to ensure a high boost pressure, and the exhaust expansion by the variable exhaust resistance muffler is promoted to mute An engine with a supercharger that obtains high torque while enhancing the effect has been proposed.
[0003]
When the turbo-supercharger operation is switched and the exhaust resistance variable muffler valve is switched, the secondary turbo is turned off when the engine moves from a high-speed range with a high exhaust flow rate to a low-speed range with a low exhaust gas flow rate. The turbocharger switches from operating to non-operating to increase the flow rate of the exhaust gas flow that flows through the turbine of the primary turbocharger. At the same time, the exhaust resistance of the variable exhaust resistance muffler increases, and the primary turbo Since the turbocharger turbine is decelerated to produce a turbo lag, Japanese Patent Laid-Open No. 3-92538 discloses only the primary turbocharger from the twin turbo state by the supercharging operation of both turbochargers. After the transition to the single turbo mode of operation, the valve of the exhaust resistance variable muffler (exhaust silencer) is closed from the open state after a predetermined period of time. And, during this time, by keeping the low emissions mode of exhaust resistance, a technique for preventing the occurrence of turbo lag to alleviate the deceleration of the turbine of the primary turbosupercharger is disclosed.
[0004]
[Problems to be solved by the invention]
However, according to the preceding example, the exhaust resistance variable muffler valve is closed and opened on the low-load low-rotation side of the switching line for closing and opening the exhaust control valve and the intake control valve depending on the engine load and the engine speed. This is handled by setting a switching line, which is simply provided with hysteresis in the switching line depending on the engine speed and engine load, and is in a twin turbo state due to the supercharging operation of both turbochargers during deceleration, etc. Is not necessary when the engine speed and load change instantaneously, such as when it is possible to prevent the occurrence of turbo lag at the time of transition from single turbo to single turbo, where only the primary turbocharger operates In addition, the exhaust resistance variable muffler valve opens and closes to cause hunting.
[0005]
In addition, when the exhaust resistance variable muffler valve is stuck open, a sufficient silencing effect due to exhaust gas expansion cannot be obtained under single turbo conditions where the exhaust gas flow rate is low. If the valve is closed, the exhaust resistance increases and the exhaust efficiency decreases and the engine output performance deteriorates under twin turbo conditions where the exhaust gas flow rate is large. In other words, it is not possible to confirm the valve sticking of the valve, that is, it is not possible to easily confirm the operation of the valve of the variable exhaust resistance type muffler.
[0006]
  The present invention has been made in view of the above circumstances., ExhaustTo provide an exhaust resistance variable muffler operation confirmation device capable of easily confirming the operation of a variable air resistance muffler.It is an object.
[0007]
[Means for Solving the Problems]
  UpNoteIn order to achieve the objective, the invention of claim 1The exhaust system of the engine is equipped with a variable exhaust resistance muffler with multiple exhaust modes with different exhaust resistance. When the exhaust gas flow rate is low, the exhaust resistance variable muffler valve is closed to provide an exhaust mode with a large exhaust resistance. In the exhaust resistance variable muffler operation confirmation device, the exhaust resistance variable muffler valve is opened when the gas flow rate is set to an exhaust mode with a small exhaust resistance.As shown in the basic configuration diagram ofMode switching means for switching between the normal operation mode in the normal operation state and the test mode for confirming the operation of the valve, and when the test mode is selected, when a preset condition is satisfied, the variable exhaust resistance type muffler Forced opening and closing means for forcibly opening and closing the valve;It is provided with.
[0008]
  According to a second aspect of the present invention, in the first aspect of the present invention, the setting condition is an idling time while the vehicle is stopped.It is characterized by that.
[0009]
  The invention according to claim 3 is the claim1 orIn the invention according to 2,When the test mode is selected, the valve is forcibly opened and closed every set time.It is characterized by that.
[0010]
  That is, the invention according to claim 1When the normal operation mode is selected by the mode switching means, the exhaust resistance variable muffler valve is closed when the exhaust gas flow rate is low, and the exhaust mode with a large exhaust resistance is closed. The valve is opened to enter a normal operation state in which the exhaust mode with a low exhaust resistance is set. Further, when the test mode for confirming the operation of the valve is selected by the mode switching means, the valve of the exhaust resistance variable muffler is forcibly opened and closed when a preset condition is satisfied. Therefore, by selecting the test mode, it is possible to easily confirm the valve sticking of the exhaust resistance variable muffler and the failure of the valve operating system. In this case, in the second aspect of the invention, the set condition is set to the idling state while the vehicle is stopped, and in the third aspect of the invention, when the test mode is selected, the valve is forcibly opened and closed every set time. .
[0012]
[Embodiments of the Invention]
Hereinafter, an embodiment of the present invention will be described with reference to FIGS. First, in FIG. 20, the overall configuration of a supercharged engine to which the present invention is applied will be described.
[0013]
Reference numeral 1 denotes an engine with a supercharger (in this embodiment, a horizontally opposed four-cylinder engine). In the left and right banks 3 and 4 of the crankcase 2, a combustion chamber 5, an intake port 6, an exhaust port 7, a spark plug 8, A valve operating mechanism 9 and the like are provided. The left bank 3 has # 2, # 4 cylinders, and the right bank 4 has # 1, # 3 cylinders. In addition, the primary turbocharger 40 and the secondary turbocharger 50 are respectively disposed immediately after the left and right banks 3 and 4 due to the engine shortened shape. As an exhaust system, a common exhaust pipe 10 from both the left and right banks 3 and 4 communicates with the turbines 40a and 50a of both turbochargers 40 and 50, and the exhaust pipe 11 from the turbines 40a and 50a is one exhaust pipe 12. Are connected to the catalytic converter 13 and the exhaust resistance variable muffler 14.
[0014]
The primary turbocharger 40 is a low-capacity low-speed type with a large supercharging capability in a low and medium speed range, while the secondary turbocharger 50 has a large capacity with a large supercharging capability in a medium and high-speed range. High speed type. For this reason, since the primary turbocharger 40 has a smaller capacity, the exhaust resistance increases.
[0015]
As an intake system, the intake pipe 16 from the downstream of the air cleaner 15 is branched into two intake pipes 17a and 17b, and the intake pipes 17a and 17b communicate with the compressors 40b and 50b of the turbochargers 40 and 50, respectively. The intake pipes 18 and 19 from the compressors 40 b and 50 b are communicated with the intercooler 20. The intercooler 20 communicates with the chamber 22 through a throttle body 27 having a throttle valve 21, and the chamber 22 communicates with an intake port 6 of each cylinder of the left and right banks 3 and 4 through an intake manifold 23. Further, as an idle control system, a check valve that bypasses the throttle valve 21 and communicates with the intake manifold 16 directly downstream of the air cleaner 15 and the intake manifold 23 is opened to the idle control valve (ISCV) 25 with a negative pressure. 26 is provided to control the amount of intake air during idling or deceleration.
[0016]
Further, as a fuel system, an injector 30 is disposed immediately upstream of the intake port 6 in each cylinder of the intake manifold 23, and a fuel passage 33 from a fuel tank 32 having a fuel pump 31 includes a filter 34 and a fuel pressure regulator 35. And communicated with the injector 30. The fuel pressure regulator 35 adjusts according to the intake pressure in the intake manifold, thereby maintaining the fuel pressure supplied to the injector 30 at a constant height with respect to the intake pipe pressure. It is possible to control the fuel injection amount by driving the injector 30 by the pulse width of the injection signal from the apparatus 100. The ignition system is connected so that an ignition signal from the igniter 36 is input to each ignition coil 8 a provided continuously for each ignition plug 8.
[0017]
Next, the operation system of the primary turbocharger 40 will be described.
[0018]
The primary turbocharger 40 operates to rotate the compressor 40b by the energy of the exhaust gas introduced into the turbine 40a, and to always supercharge by sucking and pressurizing air. A primary wastegate valve 41 including a diaphragm actuator 42 is provided on the turbine 40a side. A control pressure passage 44 directly downstream of the compressor 40b communicates with the pressure chamber of the actuator 42 through an orifice 48 so that the waste gate valve 41 can be opened with good response when the boost pressure rises above a set value. The The control pressure passage 44 further communicates the supercharging pressure with a duty solenoid valve D.SOL.1 that leaks upstream of the compressor 40b. The duty solenoid valve D.SOL.1 generates a predetermined control pressure. Acting on the actuator 42, the boost pressure control is performed by changing the opening of the waste gate valve 41. Here, the duty solenoid valve D.SOL.1 is actuated by a duty signal from the electronic control unit 150 described later, and when the duty ratio of the duty signal is small, the opening degree of the wastegate valve 41 is increased with a high control pressure. As the duty ratio is increased, the control pressure is reduced by increasing the leak amount, and the opening degree of the waste gate valve 41 is decreased to increase the supercharging pressure.
[0019]
On the other hand, in order to prevent a decrease in the compressor speed and intake noise when the throttle valve is suddenly closed, a bypass is provided between the outlet side of the intercooler 20 near the throttle valve 21 and the upstream side of the compressor 40b as a downstream side of the compressor 40b. A passage 46 is communicated. An air bypass valve 45 is provided in the bypass passage 46 so that the manifold negative pressure is introduced and opened by the passage 47 when the throttle valve is suddenly closed, and the compressed air confined downstream of the compressor 40b is quickly leaked.
[0020]
The operation system of the secondary turbocharger 50 will be described.
[0021]
Similarly, the secondary turbocharger 50 is a turbocharger in which the turbine 50a and the compressor 50b are rotationally driven by exhaust, and a secondary wastegate valve 51 including an actuator 52 is provided on the turbine 50a side. Further, the exhaust pipe 10 upstream of the turbine 50a is provided with a downstream opening type exhaust control valve 53 having a diaphragm actuator 54, and a butterfly type intake control having a similar actuator 56 downstream of the compressor 50b. A valve 55 is provided, and a boost pressure relief valve 57 is provided in a relief passage 58 that communicates between the upstream and downstream of the compressor 50b.
[0022]
The operation system of these valves will be described.
[0023]
First, a surge tank 60 serving as a negative pressure source communicates with the intake manifold 23 through a passage 61 having a check valve 62 to store negative pressure and buffer pulsation pressure when the throttle valve 21 is fully closed. In addition, a supercharging pressure relief valve switching solenoid valve SOL. 1. Intake control valve switching solenoid valve SOL. 2, first and second exhaust control valve switching solenoid valves SOL. 3, 4, duty solenoid valve D.SOL.2 for controlling the exhaust control valve 53 to be slightly opened, and switching solenoid valve SOL. For the secondary wastegate valve for opening and closing the secondary wastegate valve 51. W. Each switching solenoid valve SOL. W, SOL. 1-4 are negative pressures from the surge tank 60 via the negative pressure passage 63 by the ON / OFF signals from the electronic control unit 150, positive pressures from the positive pressure passages 64a and 64b communicating downstream of the intake control valve 55, Alternatively, the atmospheric pressure or the like is selected and guided to the actuator side by the control pressure passages 70a to 74a, and the secondary waste gate valve 51, the boost pressure relief valve 57, and the control valves 55 and 53 are operated. Further, the duty solenoid valve D.SOL.2 regulates the positive pressure acting on the positive pressure chamber 54a of the actuator 54 by the duty signal from the electronic control device 150, and controls the exhaust control valve 53 to be opened small.
[0024]
Switching solenoid valve SOL. 1, when energization is turned off, the positive pressure passage 64a side is closed and the negative pressure passage 63 side is opened, and a negative pressure is applied to the pressure chamber in which the spring of the boost pressure relief valve 57 is housed via the control pressure passage 71a. To open the boost pressure relief valve 57 against the biasing force of the spring. When turned ON, the negative pressure passage 63 side is closed and the positive pressure passage 64 a side is opened, and the positive pressure is introduced into the pressure chamber of the supercharging pressure relief valve 57 to close the supercharging pressure relief valve 57.
[0025]
Inlet control valve switching solenoid valve SOL. 2 is closed against the urging force of the spring by closing the atmospheric port and opening the side of the negative pressure passage 63 when it is turned off, and leading negative pressure to the pressure chamber in which the spring of the actuator 56 is housed via the control pressure passage 72a. Then, when the intake control valve 55 is closed and turned on, the negative pressure passage 63 side is closed, the atmospheric port is opened, the atmospheric pressure is guided to the pressure chamber of the actuator 56, and the intake control valve 55 is opened by the urging force of the spring in the pressure chamber. .
[0026]
Secondary wastegate valve switching solenoid valve SOL. W is turned OFF only when it is determined that high-octane gasoline is used based on the ignition advance amount learned in accordance with the presence or absence of knock in the ignition timing control by the electronic control unit 150, and is turned ON when it is determined that regular gasoline is used. The And the switching solenoid valve SOL. When W is turned OFF, the passage 65 communicating upstream of the intake control valve 55 is closed, the atmospheric port is opened, and the atmospheric pressure is introduced into the actuator 52 via the control pressure passage 70a. The secondary wastegate valve 51 is closed by the biasing force of the spring. Further, the atmospheric port is closed when ON and the passage 65 side is opened, and the supercharging pressure downstream of the secondary turbocharger 50 when the turbochargers 40, 50 are operated is guided to the actuator 52, and according to this supercharging pressure. The secondary wastegate valve 51 is opened, so that the boost pressure is relatively lowered when using regular gasoline as compared with when using high-octane gasoline.
[0027]
The first exhaust control valve switching solenoid valve SOL. 3 to the positive pressure chamber 54a of the actuator 54 that operates the exhaust control valve 53, the second exhaust control valve switching solenoid valve SOL. 4 communicates with the negative pressure chamber 54b in which the spring of the actuator 54 is housed. And both switching solenoid valves SOL. When both of 3 and 4 are OFF, the first exhaust control valve switching solenoid valve SOL. 3 closes the positive pressure passage 64b side and opens the atmospheric port, and the second solenoid valve SOL. 4 closes the negative pressure passage 63 side and opens the atmospheric port, whereby both chambers 54a and 54b of the actuator 54 are opened to the atmosphere, and the exhaust control valve 53 is fully closed by the biasing force of a spring built in the negative pressure chamber 54b. . Further, both switching solenoid valves SOL. When both 3 and 4 are ON, the atmospheric ports are closed, and the first exhaust control valve switching solenoid valve SOL. 3 opens the positive pressure passage 64b side, the second exhaust control valve switching solenoid valve SOL. 4 opens the side of the negative pressure passage 63, thereby introducing a positive pressure into the positive pressure chamber 54a of the actuator 54 and a negative pressure into the negative pressure chamber 54b, and fully opening the exhaust control valve 53 against the biasing force of the spring.
[0028]
The first exhaust control valve switching solenoid valve SOL. 3 is provided with an orifice 67. A leak passage 66 is communicated with the downstream side of the orifice 67 and the intake pipe 17a. The duty solenoid for controlling the small opening of the exhaust control valve is connected to the leak passage 66. Valve D.SOL.2 is provided. The first exhaust control valve switching solenoid valve SOL. 3 is ON, positive pressure is supplied to the positive pressure chamber 54a of the actuator 54, and the negative pressure chamber 54b is opened to the atmosphere. The exhaust solenoid valve 53 leaks the positive pressure by the duty solenoid valve D.SOL.2. Small open. Here, when the duty ratio in the duty signal from the electronic control unit 150 is large, the duty solenoid valve D.SOL.2 reduces the positive pressure acting on the positive pressure chamber 54a due to the increase in the leak amount, and the exhaust control valve 53 As the opening degree is reduced and the duty ratio is reduced, the leak amount is reduced, the positive pressure is kept higher, and the opening degree of the exhaust control valve 53 is increased. When the engine operating region is in the predetermined exhaust control valve small opening control region under the single turbo mode in which only the primary turbocharger 40 is supercharged, the exhaust solenoid control valve 53 is opened by the duty solenoid valve D.SOL.2. The supercharging pressure is feedback-controlled at a degree, and the exhaust control valve 53 is opened slightly in accordance with the supercharging pressure control to pre-rotate the secondary turbocharger to prepare for the transition to the twin turbo state.
[0029]
Next, various sensors will be described.
[0030]
A differential pressure sensor 80 is provided for detecting the differential pressure downstream of the intake control valve 55, and an absolute pressure sensor 81 is used to switch the intake pipe pressure (the intake pressure in the intake manifold 23) and the atmospheric pressure by the switching solenoid valve 76. It is provided to select and detect.
[0031]
A knock sensor 82 is attached to the engine body 1, a water temperature sensor 83 is exposed to the cooling water passage communicating the left and right banks 3, 4, and an O 2 sensor 84 is exposed to the exhaust pipe 10. Further, a throttle sensor 85 including a throttle opening sensor 85a and an idle switch 85b for detecting the throttle fully closed is connected to the throttle valve 21, and an intake air amount sensor 86 is disposed immediately downstream of the air cleaner 15. .
[0032]
In addition, a crank rotor 90 is mounted on the crankshaft 1 a supported on the engine body 1, and electromagnetic waves that detect protrusions corresponding to a predetermined phrase rank angle formed on the crank rotor 90 are formed on the outer periphery of the crank rotor 90. A crank angle sensor 87 composed of a pickup or the like is provided. Further, a cam angle sensor 88 for cylinder discrimination composed of an electromagnetic pickup or the like is provided on the cam rotor 91 connected to the camshaft of the valve mechanism 9 that rotates 1/2 with respect to the crankshaft 1a.
[0033]
The crank rotor 90 has protrusions formed on the outer periphery thereof corresponding to a predetermined crank angle, and the electronic control unit 150 (to be described later) inputs a protrusion detected by a crank angle sensor 87, that is, a crank angle signal (crank pulse). The engine speed is calculated from the interval time, and the cylinder is discriminated from an interrupt signal (cam pulse input) when the cam angle sensor 88 detects a cylinder discriminating protrusion formed on the outer periphery of the cam rotor 91.
[0034]
Next, the first-stage exhaust resistance variable muffler 14 will be described with reference to FIGS. In the exhaust resistance variable muffler 14, two tail pipes 102a and 102b are communicated with the muffler main body 101, and an exhaust mode switching valve 103 is disposed on one tail pipe 102a. The exhaust mode switching valve 103 is linked to the actuator motor 105 via the wire 104, and is sent from the motor actuator controller (ACTR) 106 to the actuator motor 105 via the valve closing signal line. As shown in FIG. 3, when a predetermined time TCON (for example, 3 sec) and an ON signal (valve closing signal) are output, the actuator motor 105 rotates in the forward direction and the urging force of the spring 103a provided in the valve 103 The valve 103 is closed. However, when the valve 103 is fully closed, the valve 103 is stopped at the fully closed position by a fully closed stopper (not shown).
[0035]
Further, when an AC signal is output from the ACTR 106 to the actuator motor 105 through the valve opening signal line for a predetermined time TCON (for example, 3 sec) and an ON signal (valve opening signal) is output, the actuator motor 105 is reversely rotated to attach the spring 103a. The valve 103 opens against the force. Also in this case, when the valve 103 is fully opened, the valve 103 is stopped at the fully opened position by a fully opened stopper (not shown).
[0036]
The ACTR 106 outputs a valve closing signal to the actuator motor 105 when the signal from the electronic control unit 150 is switched from OFF to ON, as shown in the time chart of FIG. When the signal is switched from ON to OFF, a valve open signal is output to the actuator motor 105.
[0037]
In the twin turbo mode in the high speed range where both the primary turbocharger 40 and the secondary turbocharger 50 are supercharged, as shown in FIG. 23 (a), the exhaust of the exhaust resistance variable muffler 14 is exhausted. By opening the valve 103 for mode switching to an exhaust mode with less exhaust resistance, it is possible to cope with higher engine output due to the twin turbo state of both turbocharger operations and an increase in the exhaust gas flow rate at this time. In the single turbo mode in the low speed range where only the primary turbocharger 40 is supercharged, the exhaust resistance is reduced as shown in FIG. 23 (b). By closing the valve 103 of the variable muffler 14 to the exhaust mode with a large exhaust resistance, when the exhaust gas flow rate is small, the primary turbocharger 40 is concentrated. The exhaust gas is supplied to increase the flow rate of the exhaust gas flow flowing through the turbine 40a of the primary turbocharger 40 to ensure a high supercharging pressure even in the single turbo mode, and the exhaust resistance variable muffler 14 can expand the exhaust gas. Promote to ensure high torque while enhancing the silencing effect.
[0038]
Next, the configuration of the electronic control unit (ECU) 150 will be described with reference to FIG. The ECU 150 includes a main computer 160 that performs engine control such as fuel injection control, ignition timing control, idle speed control, supercharger switching control, supercharging pressure control, etc., and exhaust control by the variable exhaust resistance muffler 14, etc. A constant voltage circuit 180 that supplies a predetermined stabilized power supply to each unit, a drive circuit 181 connected to the main computer 160, and an A / D converter. Various peripheral circuits connected to the device 182 and the sub computer 170 are incorporated.
[0039]
The constant voltage circuit 180 is connected to the battery 111 directly and via the first relay contact of the power relay 110, and the relay coil of the power relay 110 is connected to the battery 111 via the ignition switch 112. When the ignition switch 112 is turned on and the relay contact of the power relay 110 is closed, control power is supplied to the computers 160 and 170. The second relay contact of the power relay 110 is connected to the power line to each actuator and the relay contact of the fuel pump relay 113, and the fuel pump 31 is connected to the fuel pump relay 113. Is connected to the battery 111 via a relay contact.
[0040]
The main computer 160 is a microcomputer in which a CPU 161, a ROM 162, a RAM 163, a backup RAM 164, a counter / timer group 165, an SCI 166 as a serial communication interface, and an I / O interface 167 are connected via a bus line. Regardless of whether the ignition switch 112 is turned on or off, the RAM 164 is always supplied with backup power from the constant voltage circuit 180 directly connected to the battery 111 and holds data.
[0041]
The counter / timer group includes a free run counter, various counters such as a cam pulse input counting counter for cylinder discrimination, a fuel injection timer, an ignition timer, a periodic interrupt timer for generating a periodic interrupt, and a previous crank pulse. Various timers such as an input interval timing timer and a watchdog timer for system abnormality monitoring are collectively referred to for convenience. In the main computer 160, other various software counters and timers are used.
[0042]
Similarly to the main computer 160, the sub-computer 170 is a microcomputer in which a CPU 171, ROM 172, RAM 173, counter / timer group 174, SCI 175, and I / O interface 176 are connected via a bus line. The computer 160 and the sub computer 170 are connected to each other by a serial communication line via the SCI 166 and 175.
[0043]
The input port of the I / O interface 167 of the main computer 160 includes a crank angle sensor 87, a cam angle sensor 88, a vehicle speed sensor 92, an idle switch 85b, and a neutral switch 93 that is turned on at the neutral position of the transmission and detects a neutral state. The ignition switch 112 and the starter switch 114 are connected, and the intake air amount sensor 86, the throttle opening sensor 85a, the water temperature sensor 83, the O2 sensor 84, the absolute pressure sensor 81, and the differential pressure sensor 80 are connected to the A / D converter. Further, the voltage VB of the battery 111 is input to the A / D converter 182 and monitored.
[0044]
An igniter 36 is connected to the output port of the I / O interface 167, and the boost solenoid relief valve switching solenoid valve SOL. 1. Intake control valve switching solenoid valve SOL. 2, first and second exhaust control valve switching solenoid valve SOL. 3, 4, Duty solenoid valve D.SOL.1 for primary wastegate valve control, Duty solenoid valve D.SOL.2 for exhaust control valve small opening control, Switching solenoid valve SOL. W, intake pipe pressure / atmospheric pressure switching solenoid valve 76, each actuator such as injector 30, ISCV 25, ACTR 106 that outputs a valve open / close signal to actuator motor 105 that opens and closes valve 103 of exhaust resistance variable muffler 14; And the relay coil of the fuel pump relay 113 is connected via the drive circuit 181.
[0045]
The I / O interface 167 is connected to a test mode switch 120 and a read memory switch 121 each comprising a connector grounded at one end as mode switching means. When at least one of the test mode switch 120 and the read memory switch 121 is OFF (connector released state), a normal operation mode in which the exhaust resistance variable muffler 14 is normally operated is set. The valve 103 of the variable muffler 14 is closed to an exhaust mode with a large exhaust resistance, and the valve 103 of the variable exhaust muffler 14 is opened to an exhaust mode with a low exhaust resistance when the exhaust gas flow rate is high in a twin turbo state. When the test mode switch 120 and the read memory switch 121 are both ON (connector connection state), the test mode for confirming the operation of the valve 103 of the exhaust resistance variable muffler 14 is entered, and a preset condition ((vehicle Exhaust resistance when the vehicle is idle) Henshiki forcibly opened and closed at predetermined time intervals a valve muffler. Therefore, by selecting a test mode, it is possible to easily inspect the easily sticking of the valve 130 of the exhaust resistance variable muffler 14
During normal use, both the test mode switch 120 and the read memory switch 121 are turned off to enter the normal operation mode, and the operator turns on both the switches 120 and 121 at the time of inspection and repair. Select a mode. Then, both switches 120 and 121 are turned off at the end of inspection and repair.
[0046]
On the other hand, a crank angle sensor 87 and a cam angle sensor 88 are connected to an input port of the I / O interface 176 of the sub computer 170, and a knock sensor 82 includes an amplifier 183, a frequency filter 184, and an A / D converter 185. After the knock detection signal from the knock sensor 82 is amplified to a predetermined level by the amplifier 183, a necessary frequency component is extracted by the frequency filter 184, and is digitally converted by the A / D converter 185. It is converted into a signal and input. The main computer 160 processes detection signals from the sensors and switches, and controls engine control such as fuel injection control, ignition timing control, idle speed control, supercharger switching control, supercharging pressure control, and exhaust resistance. Exhaust control is performed by a variable muffler. On the other hand, the sub-computer 170 specifies a sample section of the signal from the knock sensor 82 based on the engine speed and the engine load, and the signal from the knock sensor 82 in this sample section. A / D conversion is performed at high speed to convert the vibration waveform into digital data faithfully, and the presence or absence of knocking is determined based on this data.
[0047]
The output port of the I / O interface 176 of the sub computer 170 is connected to the input port of the I / O interface 167 of the main computer 160, and knock determination data in the sub computer 170 is transmitted from the I / O interface 176. The data is output to the I / O interface 167 of the main computer 160. The main computer 160 reads the knock data from the sub computer 170 via the serial communication line via the SCI 166 and 175 when the determination result indicating that the knock has occurred is output from the sub computer 170, and immediately applies the corresponding data based on the knock data. Delay the ignition timing of the cylinder to avoid knocking.
[0048]
In such an engine control system, when the ignition switch 112 is turned on, the power relay 110 is turned on, a constant voltage is supplied to each part via the constant voltage circuit 180, and the ECU 150 is activated. In the main computer 160, the CPU 161 processes detection signals from the sensors and switches, the battery voltage, and the like input via the I / O interface 167 in accordance with the program stored in the ROM 162, and stores them in the RAM 163. Various control amounts are calculated based on various data to be stored, various learning value data stored in the backup RAM 164, fixed data stored in the ROM 162, and the like. Then, a drive signal corresponding to the calculated fuel injection amount is output to the injector 30 of the corresponding cylinder at a predetermined timing to perform fuel injection control, and an ignition signal is output to the igniter 36 at a timing corresponding to the calculated ignition timing. Ignition timing control is executed, a drive signal with the calculated duty ratio is output to the ISCV 25 to perform idle speed control, and each solenoid valve SOL. 1 to 4 outputs ON and OFF signals to perform supercharger switching control. Further, according to the operating state and the operating state of each supercharger, the solenoid valve SOL. Outputs ON and OFF signals to W and outputs duty signals to duty solenoid valves D.SOL.1 and D.SOL.2 for engine control such as supercharging pressure control. An OFF signal is output and exhaust control by the exhaust resistance variable muffler 14 is executed. The sub computer 170 is a computer dedicated to the knock detection process, and therefore detailed description of its operation is omitted.
[0049]
In this case, in the turbocharger switching control, in the high speed range, both the exhaust control valve 53 and the intake control valve 55 are fully opened to supercharge the primary turbocharger 40 and the secondary turbocharger 50 together. In the low speed range, the intake control valve 55 is closed and the exhaust control valve 53 is closed or the exhaust control valve 53 is opened slightly when the operating state is in the predetermined small opening control region. A single turbo state in which only the feeder 40 is supercharged is set.
[0050]
In the exhaust control in the exhaust resistance variable muffler 14, when at least one of the test mode switch 120 and the read memory switch 121 is OFF, the normal operation mode in which the exhaust resistance variable muffler 14 is normally operated is set, and the turbocharger is operated. Depending on the state, in the single turbo state where only the primary turbocharger 40 operates, the valve 103 of the exhaust resistance variable muffler 14 is closed to set the exhaust mode with a large exhaust resistance, and in addition to the primary turbocharger 40 In the twin turbo state in which the secondary turbocharger 50 is supercharged, the valve 103 of the exhaust resistance variable muffler 14 is opened to set the exhaust mode with a low exhaust resistance. Further, after switching from the single turbo state where only the primary turbocharger 40 is supercharged to the twin turbo state where both turbochargers 40 and 50 are supercharged, the single turbo state is switched to the twin turbo state. When the engine load remains above the set value for a set time, the valve 103 of the exhaust resistance variable muffler 14 is opened. When the twin turbo state is changed to the single turbo state, the twin turbo state is changed to the single turbo state. After switching to the state, the valve 103 of the exhaust resistance variable muffler 14 is closed after the set time has elapsed, thereby preventing the occurrence of turbo lag and instantaneously changing the engine speed and load when shifting the transmission. Prevents the valve 103 of the exhaust resistance variable muffler 14 from being opened and closed unnecessarily even when the air pressure changes greatly. Is, off hunting of the valve 103 of the exhaust resistance variable muffler 14 is reliably prevented.
[0051]
Further, when both the test mode switch 120 and the read memory switch 121 are ON, the test mode for confirming the operation of the valve 103 of the exhaust resistance variable muffler 14 is entered, and a preset condition (during idling while the vehicle is stopped) is set. ) Is established, the valve 103 of the exhaust resistance variable muffler 14 is forcibly controlled to open and close every predetermined time.
[0052]
Therefore, by selecting the test mode, it is possible to easily check the adhesion of the valve 130 of the exhaust resistance variable muffler 14. That is, when both the test mode switch 120 and the read memory switch 121 are turned on (connector connection state) during inspection and repair, the test mode is set, and at this time, the valve 103, the wire 104, the actuator motor 105, the ACTR 106, etc. are normal. If there is, the valve 103 of the exhaust resistance variable muffler 14 opens and closes every predetermined time. As shown in FIG. 21, the tail pipe 101a on which the valve 103 of the exhaust resistance variable muffler 103 is disposed is located at the rear of the vehicle. Thus, the operation of the valve 103 and the wire 104 can be easily observed, and the normal operation can be confirmed by visual observation.
[0053]
Also, when the test mode is selected and the valve 103 is not operated despite idling while the vehicle is stopped, the valve 103 is stuck, the wire 104 is caught, or the actuator motor 105, the ACTR 106 is broken, or the ECU 150 This is a failure such as disconnection or short circuit of any signal line from the ACTR 106 and the ACTR 106 to the actuator motor 105, and the operator can easily determine this. Here, the idling condition when the vehicle is stopped as the set condition is that the engine operability, the superchargers 40, 50, etc. are adversely affected even if the valve 103 of the exhaust resistance variable muffler 14 is forcibly opened and closed. This is because this is a region that does not give In other words, when the valve 103 of the exhaust resistance variable muffler 14 is forcibly opened and closed every predetermined time and the exhaust mode is switched while the vehicle is running, the exhaust resistance increases and decreases in a short time, and the engine operability and The turbochargers 40 and 50 are adversely affected and drivability is deteriorated.
[0054]
  That is, the test mode switch 120 and the read memory switch 121 relate to the present invention.RumoThe function of the mode switching means is realized, and the main computer 160 of the ECU 150 relates to the present invention.StrengthThe function of the opening / closing means is realized.
[0055]
Hereinafter, the supercharger switching control process by the main computer 160 of the ECU 150 and the exhaust control process for the exhaust resistance variable muffler will be described with reference to the flowcharts shown in FIGS.
[0056]
First, when the ignition switch 112 is turned on and the ECU 150 is powered on, the system is initialized by the initialization routine shown in FIG. Each counter is initialized.
[0057]
Note that the initialization routine is performed only once at the time of startup by turning on the power, and in step S1, an ON signal is output to the ACTR 106 (GACTR ← ON). As a result, as shown in the time chart of FIG. 18, the signal from the ECU 150 to the ACTR 106 is switched from OFF to ON, and from the ACTR 106 to the actuator motor 105 via the valve closing signal line for a certain time (for example, 3 sec), the ON signal ( When the valve 103 of the exhaust resistance variable muffler 14 is open, the actuator motor 105 rotates forward and the urging force of the spring 103a attached to the valve 103 of the exhaust resistance variable muffler 14 is output. Thus, the valve 103 is closed, the tail pipe 102a is closed, and the exhaust gas is discharged from only the other tail pipe 102b. When the valve 103 is in a closed state, the valve 103 is held as it is.
[0058]
Accordingly, the exhaust mode corresponding to the single turbo state in which the exhaust gas flow rate is small immediately after the engine is started is provided, and the single turbo state immediately after the start is prepared.
[0059]
When the starter switch is turned on to crank the engine 1 and the engine 1 is operated, the engine speed N is calculated based on the crank pulse input from the crank angle sensor 87.
[0060]
First, prior to the exhaust control process for the exhaust resistance variable muffler 14, the supercharger switching control process will be described with reference to the flowcharts of the turbo switching control routine shown in FIGS.
[0061]
This turbo switching control routine is executed every set time (for example, 10 msec) after system initialization. First, in step S101, the value of the twin turbo mode determination flag F1 is referred to. If the twin turbo mode determination flag F1 is cleared, the process proceeds to step S102, and if it is set, the process proceeds to step S160. The twin turbo mode determination flag F1 is cleared when the current control state is the single turbo mode in which only the primary turbocharger 40 is supercharged, and in the twin turbo mode in which both turbochargers 40 and 50 are supercharged. Set when.
[0062]
In the following description, the single turbo mode will be described first, then the single to twin switching control, and finally the twin turbo mode will be described.
[0063]
Immediately after turning on the ignition switch 112, and when the current control state is the single turbo mode, F1 = 0, and the process proceeds to step S102.
[0064]
In step S102, a single to twin switching determination value TP2 is set by referring to the turbo switching determination value table with interpolation calculation based on the engine speed N. This single-to-twin switching determination value TP2 is for determining switching from the single turbo state to the twin turbo state. As shown in FIG. 10, the turbo switching determination value table includes a basic fuel injection pulse width TP (TP = K × Q / N; Q is an intake air amount, K is an injector characteristic) indicating the engine speed N and the engine load. From the relationship with the correction constant), the single-to-twin switching judgment line L2 for switching from the single turbo mode to the twin turbo mode and vice versa, the twin-to-single switching judgment line L1 for switching from the twin turbo mode to the single turbo mode is appropriate from experiments. A value is obtained and a single turbo region and a twin turbo region are set. The single → twin switching judgment basic value TP2 and the twin → single switching judgment basic value TP1 are stored in a series of addresses in the ROM 162 in advance as a table with the engine speed N as a parameter corresponding to each line L2, L1. ing.
[0065]
Here, it is necessary to set the single-to-twin switching determination line L2 at a point where the engine output torque curve in the single turbo state matches the engine output torque curve in the twin turbo state in order to prevent torque fluctuation at the time of switching. For this reason, as shown in FIG. 10, the engine is set to the low load side according to the increase in the engine speed N from the high load in the low and medium speed ranges. Also, as shown in the figure, in order to prevent control hunting when the secondary turbocharger 50 is switched between operation and non-operation, the twin → single switching determination line L1 is compared to the single → twin switching determination line L2. It is set with a relatively wide hysteresis on the low speed side.
[0066]
Next, the process proceeds to step S103, where the single to twin switching determination value TP2 is compared with the current basic fuel injection pulse width TP (hereinafter referred to as “engine load”). If TP <TP2, the process proceeds to step S104, where TP ≧ TP2. In this case, the process branches to step S130 and shifts to single-> twin switching control for switching from the single turbo state to the twin turbo state.
[0067]
If TP <TP2 in step S103 and the process proceeds to step S104, single turbo mode control is performed.
[0068]
In step S104, the value of the supercharging pressure control mode determination flag F2 is referred to. This supercharging pressure control mode determination flag F2 is used in the exhaust control valve small opening control mode region in which the current operation region performs supercharging pressure control by small opening of the exhaust control valve 53 and preliminarily rotates the secondary turbocharger 50. When set, cleared when out of range.
[0069]
Accordingly, immediately after the ignition switch 112 is turned on, the initial setting is performed, and when the operation area is outside the exhaust control valve small opening control mode area when the previous routine is executed, F2 = 0. It is determined whether or not the current operation region has shifted to the exhaust control valve small opening control mode region by the condition determination in step S107.
[0070]
The determination of transition to the exhaust control valve small opening control mode region is lower than the single-> twin switching determination line L2 because of the relationship between the engine speed N and the intake pipe pressure (supercharging pressure) P as shown in FIG. On the rotation low load side, that is, in the single turbo mode, in a region surrounded by a set value N2 (for example, 2650 rpm) and P2 (for example, 1120 mmHg), the throttle opening TH is not less than the set value TH2 (for example, 30 deg). When it is determined that the region has moved into the area.
[0071]
That is, the engine speed N and the set value N2 are compared in step S105, the intake pipe pressure P and the set value P2 are compared in step S106, and the throttle opening TH and the set value TH2 are compared in step S107. If N <N2, or P <P2, or TH <TH2, the process proceeds to step S108, where it is determined that the current operation region is outside the exhaust control valve small opening control mode region, and the boost pressure control mode determination flag F2 If N ≧ N2, P ≧ P2, and TH ≧ TH2, the process proceeds to step S109, and it is determined that the current operation region has shifted to the exhaust control valve small opening control mode region, and the boost pressure control mode The discrimination flag F2 is set.
[0072]
Then, the process proceeds to step S110, and the boost pressure relief valve switching solenoid valve SOL. 1 is turned OFF and the intake control valve switching solenoid valve SOL. 2 is turned off. Next, when the routine proceeds to step S112, the value of the boost pressure control mode determination flag F2 is referred to. When F2 = 0, the routine proceeds to step S113, where the first exhaust control valve switching solenoid valve SOL. 3 is turned OFF, and the second exhaust control valve switching solenoid valve SOL. 4 is turned off.
[0073]
Thereafter, in steps S115 to S117, the twin turbo mode determination flag F1, a differential pressure search flag F3 (to be described later), and a control valve switching time count value C1 are cleared, and the routine is exited.
[0074]
Therefore, in the single turbo mode and in the low rotation and low load operation region outside the exhaust control valve small opening control mode region, each switching solenoid valve SOL. 1 to 4 are all OFF. Therefore, the supercharging pressure relief valve 57 is a supercharging pressure relief valve switching solenoid valve SOL. When the negative pressure from the surge tank 60 is introduced into the pressure chamber by turning OFF, the intake control valve 55 opens the intake control valve switching solenoid valve SOL. When 2 is turned off, a negative pressure is introduced into the pressure chamber of the actuator 56, so that the valve is closed against the biasing force of the spring. Further, the exhaust control valve 53 is a switching solenoid valve SOL. When the atmospheric pressure is introduced into both chambers 54a and 54b of the actuator 54 by turning OFF 3 and 4, the valve is closed by the biasing force of the spring.
[0075]
Then, by closing the exhaust control valve 53, the introduction of exhaust gas to the secondary turbocharger 50 is cut off, the secondary turbocharger 50 becomes inoperative, and only the primary turbocharger 40 is in a single turbo state. . Further, by closing the intake control valve 55, leakage of the supercharging pressure from the primary turbocharger 40 to the secondary turbocharger 50 side via the intake control valve 55 is prevented, and the supercharging pressure is reduced. Is prevented.
[0076]
In the case of the single turbo mode and outside the exhaust control valve small opening control mode region, or in the twin turbo mode described later, the supercharging pressure feedback control is not described in detail here, but the primary wastegate valve 41 Is done using only. And this supercharging pressure control uses the absolute pressure, sets the target supercharging pressure based on the engine operating state, compares the intake pipe pressure detected by the absolute pressure sensor 81, that is, the actual supercharging pressure P, Depending on the comparison result, the ON duty (duty ratio) for the duty solenoid valve D.SOL.1 is calculated by PI control (proportional integral control), for example, and the duty signal of this ON duty is sent to the duty solenoid valve D.SOL.1. This is performed by outputting and controlling the primary waste gate valve 41.
[0077]
On the other hand, if it is determined in step S109 that the current operation region is within the exhaust control valve small opening control mode region and the boost pressure control mode determination flag F2 is set, step S118 is performed via steps S110 to S112. To the first exhaust control valve switching solenoid valve SOL. Only 3 is turned on. Therefore, the first exhaust control valve switching solenoid valve SOL. 3 is turned on, positive pressure is introduced into the positive pressure chamber 54a of the actuator 54, and the exhaust control valve 53 is opened.
[0078]
Note that, under this exhaust control valve small opening control mode, supercharging pressure feedback control is performed using the exhaust control valve 53, and the exhaust control valve 53 is slightly opened accordingly. That is, the target supercharging pressure based on the absolute pressure is compared with the actual supercharging pressure P detected by the absolute pressure sensor 81, and the exhaust control valve small opening control duty solenoid valve D is controlled by, for example, PI control according to the comparison result. Calculates the ON duty (duty ratio) for .SOL.2, outputs this ON duty signal to duty solenoid valve D.SOL.2, and executes boost pressure feedback control. Therefore, the positive pressure acting on the positive pressure chamber 54a of the actuator 54 is regulated by the duty solenoid valve D.SOL.2, and the exhaust control valve 53 is opened slightly as shown in FIG. Is used to perform supercharging pressure feedback control. A part of the exhaust gas is supplied to the turbine 50a of the secondary turbocharger 50 by the small opening of the exhaust control valve 53, and the secondary turbocharger 50 is preliminarily rotated to prepare for the transition to the twin turbo state.
[0079]
Under this state, since the intake control valve 55 is closed, the boost pressure between the downstream of the compressor 50b of the secondary turbocharger 50 and the intake control valve 55 (compressor pressure by the secondary turbocharger 50). However, at this time, the supercharging pressure is leaked by opening the supercharging pressure relief valve 57 to facilitate the preliminary rotation.
[0080]
Further, when the engine operating region is in the exhaust control valve small opening control mode region under the single turbo mode and the supercharging pressure control mode determination flag F2 is set (F2 = 1), the steps S104 to S120 are performed. Then, it is determined whether or not the current operation region has shifted to the outside of the exhaust control valve small opening control mode region based on the condition determination in steps S120 to S122.
[0081]
In order to prevent control hunting at the time of switching to the supercharging pressure control mode, the determination of transition to the outside of this region is performed as shown in FIG. 2600 rpm), P1 (for example, 1070 mmHg), TH1 (for example, 25 deg). In step S120, the engine speed N is compared with the set value N1, in step S121, the intake pipe pressure (supercharging pressure) P is compared with the set value P1, and in step S122, the throttle opening TH and the set value TH1 are compared. If N <N1, or P <P1, or TH <TH1, it is determined that the current operation region has shifted to the outside of the exhaust control valve small opening control mode region, and the process proceeds to step S108 described above. The pressure control mode determination flag F2 is cleared. As a result, the exhaust control valve small opening control is canceled. If N ≧ N1, P ≧ P1, and TH ≧ TH1, it is determined that the current operation region remains within the exhaust control valve small opening control mode region, and the process proceeds to step S109, where the boost pressure control mode is set. The determination flag F2 is maintained in the state of F2 = 1, and the exhaust control valve small opening control is continued.
[0082]
As described above, under the single turbo mode, most of the exhaust from the engine 1 is introduced into the primary turbocharger 40, and the turbine 40a rotates the compressor 40b. Therefore, air is sucked and compressed by the compressor 40b, the compressed air is cooled by the intercooler 20, the flow rate is adjusted by the opening degree of the throttle valve 21, and supplied to each cylinder through the chamber 22 and the intake manifold 23 with high filling efficiency. Supercharged. In the single turbo state in which only the primary turbocharger 40 is operated in the single turbo mode, the output characteristics by the supercharging operation of the primary turbocharger 40 causes a single turbo with a high shaft torque in a low and medium rotational speed range. Torque curve is obtained.
[0083]
Next, single to twin switching control will be described.
[0084]
If it is determined in step S103 that TP ≧ TP2, that is, the current operation region has shifted from the single turbo region to the twin turbo region (see FIG. 10) at the single to twin switching determination line L2, the process branches to step S130. Then, the single-to-twin switching control for switching from the single turbo state in which only the primary turbocharger 40 is operated to the twin turbo state in which both turbochargers 40 and 50 are operated is executed.
[0085]
Then, in step S130, the boost pressure relief valve switching solenoid valve SOL. 1 is determined. In step S132, the first exhaust control valve switching solenoid valve SOL. 3 is determined, and both switching solenoid valves SOL. If both 1 and 3 are ON, the process proceeds to step S134 as it is. The switching solenoid valves SOL. When 1 and 3 are OFF, after turning ON in steps S131 and S133, the process proceeds to step S134.
[0086]
Therefore, the supercharging pressure relief valve 57 is a supercharging pressure relief valve switching solenoid valve SOL. When the positive pressure from the positive pressure passage 64a is introduced into the pressure chamber when 1 is turned on, the valve is immediately closed by the positive pressure and the biasing force of the spring. Further, the exhaust control valve 53 includes a first exhaust control valve switching solenoid valve SOL. 3 is turned on when positive pressure is introduced into the positive pressure chamber 54a of the actuator 54. In addition, when the exhaust control valve small opening control mode under the single turbo mode is shifted to the single to twin switching control, the supercharging pressure feedback control by the exhaust control valve 53 is stopped, and the exhaust control valve small opening control duty solenoid is performed. The valve D.SOL.2 is fully closed, and the positive pressure through the positive pressure passage 64b is directly introduced into the positive pressure chamber 54a of the actuator 54 without being leaked by the duty solenoid valve D.SOL.2. The opening degree of the exhaust control valve 53 is increased.
[0087]
Then, the relief passage 58 is shut off by closing the supercharging pressure relief valve 57, and the rotational speed of the secondary turbocharger 50 is increased by opening the exhaust control valve 53 and increasing its opening, and the secondary The supercharging pressure between the compressor 50b downstream of the turbocharger 50 and the intake control valve 55 is gradually increased to prepare for the transition to the twin turbo mode.
[0088]
In step S134, the value of the differential pressure search flag F3 is referred to. If F3 = 0, the process proceeds to step S135. If F3 = 1, the process jumps to step S139.
[0089]
After the transition from single to twin switching control, since F3 = 0 when the first routine is executed, the process proceeds to step S135. First, referring to the exhaust control valve opening delay time setting table with interpolation calculation based on the vehicle speed VSP, single → An exhaust control valve opening delay time T1 for setting a timing for fully opening the exhaust control valve 53 after the transition to the twin switching control (turning the second exhaust control valve switching solenoid valve SOL.4 from ON to OFF) is set, and step S136 is performed. Referring to the intake control valve opening delay time set value table with interpolation calculation based on the vehicle speed VSP, after the exhaust control valve 53 is fully opened, the intake control valve 55 is opened (the intake control valve switching solenoid valve SOL. The intake control valve opening delay time T2 for setting the start timing condition is set. Further, in step S137, the intake control valve opening differential pressure setting table is interpolated based on the differential pressure between the upstream pressure PU and downstream pressure PD of the intake control valve 55 (read value of the differential pressure sensor 80) DPS (= PU -PD). With reference to the calculation, the intake control valve differential pressure DPSST for determining the opening control start timing of the intake control valve 55 is set.
[0090]
FIG. 12 shows a conceptual diagram of the exhaust control valve opening delay time setting table, and FIG. 13 shows a conceptual diagram of the intake control valve opening delay time setting table. As shown in the figure, the higher the vehicle speed VSP is, the shorter the exhaust control valve opening delay time T1 and the intake control valve opening delay time T2, and the timing for fully opening the exhaust control valve 53 and the timing for opening the intake control valve 55, that is, The timing for switching to the twin turbo mode is advanced, the acceleration response is made uniform regardless of the vehicle speed, and the drivability is improved.
[0091]
FIG. 14 is a conceptual diagram of the intake control valve opening differential pressure setting table. As shown in the figure, the differential pressure DPS immediately after the engine operating state shifts from the single turbo region to the twin turbo region (see FIG. 10) at the single → twin switching determination line L2 (single → twin switching determination value TP2). Is more negative, that is, the downstream pressure PD is higher than the upstream pressure PU of the intake control valve 55, and the higher the supercharging state, the more the intake control valve opening differential pressure DPSST becomes negative, and the intake control valve 55 is The opening timing is advanced and the acceleration response is improved.
[0092]
After setting the delay times T1 and T2 and the intake control valve opening differential pressure DPSST, the process proceeds to step S138, the differential pressure search flag F3 is set, and the process proceeds to step S139.
[0093]
In step S139, the second exhaust control valve switching solenoid valve SOL. 4 to determine whether the fully open control for the exhaust control valve 53 has already been started. If 4 = ON and the fully open control for the exhaust control valve 53 has already been started, the routine jumps to step S144 to determine the valve opening timing for the intake control valve 55. In addition, SOL. When 4 = OFF, the exhaust control valve full open control is not yet executed, so the process proceeds to step S140, where the control valve switching time count value C1 is compared with the exhaust control valve open delay time T1, and the single to twin switching control is performed. After the shift, it is determined whether the exhaust control valve opening delay time T1 has elapsed.
[0094]
When C1 <T1, the routine proceeds to step S141, where the control valve switching time count value C1 is incremented and the routine is exited as it is, and when C1 ≧ T1, the operation area stays in the twin turbo area and shifts to single to twin switching control. Thereafter, when the exhaust control valve opening delay time T1 has elapsed, the routine proceeds to step S142, where the second exhaust control valve switching solenoid valve SOL. 4 is turned ON and the exhaust control valve 53 is fully opened. By fully opening the exhaust control valve 53, the rotational speed of the secondary turbocharger 50 is further increased, and the compressor pressure (supercharging pressure) by the secondary turbocharger 50 between the compressor 50b and the intake control valve 55 is also increased. As shown in FIG. 16, the differential pressure DPS between the upstream and downstream sides of the intake control valve 55 increases.
[0095]
Thereafter, the process proceeds to step S143, and the control valve switching time count value C1 is cleared in order to measure the time after the exhaust control valve full open control, and the process proceeds to step S144.
[0096]
Then, when proceeding from step S139 or step S143 to step S144, the count value C1 representing the time after exhaust control valve full open control (SOL.4 OFF → ON) is compared with the intake control valve open delay time T2, and C1 In the case of <T2, it is determined that the intake control valve 55 opening condition is not satisfied, and the count value C1 is incremented in step S141, and the routine is exited. If C1 ≧ T2, it is determined that the valve opening condition is satisfied, and the process proceeds to step S145, where the current differential pressure DPS and the intake control valve open differential pressure DPSST are compared, and the valve opening start timing of the intake control valve 55 is reached. Determine whether you have reached.
[0097]
When DPS <DPSST, it is determined that the valve opening start timing has not been reached, and the process proceeds to step S146. When DPS ≧ DPSST, the upstream pressure PU and the downstream pressure PD of the intake control valve 55 are substantially equal, That is, the supercharging pressure by the secondary turbocharger 50 between the compressor 50b of the secondary turbocharger 50 and the intake control valve 55 rises and becomes substantially equal to the supercharging pressure by the primary turbocharger 40, and the intake air When it is determined that the control valve opening start timing has been reached, the routine proceeds to step S147, where the intake control valve switching solenoid valve SOL. 2 is turned on and the intake control valve 55 is opened.
[0098]
As a result, supercharging from the secondary turbocharger 50 is started and a twin turbo state is established. Then, the process proceeds to step S148, and upon completion of the single to twin switching control, the twin turbo mode determination flag F1 is set to shift to the twin turbo mode next time, and the routine is exited.
[0099]
When it is determined in step S145 that DPS <DPSST and the process proceeds to step S146, the count value C1 is further compared with a value obtained by adding the set value TDP to the intake control valve opening delay time T2, and C1 < When T2 + TDP, the routine proceeds to step S141, the count value C1 is incremented and the routine is exited. When C1 ≧ T2 + TDP, the routine proceeds to step S147, and the intake control valve even if the differential pressure DPS does not reach the intake control valve opening differential pressure DPSST Switching solenoid valve SOL. 2 is turned ON, and the intake control valve 55 is opened to shift to the twin turbo mode.
[0100]
That is, if the differential pressure DPS by the differential pressure sensor 80 does not increase due to a failure of the differential pressure sensor 80 system, the first set time by the exhaust control valve opening delay time T1 has elapsed, and after the exhaust control valve 53 is fully opened, Further, after the second set time due to the intake control valve opening delay time T2 has elapsed, the intake control valve 55 is not opened at any time, during which the compressor 50b and the intake control valve 55 of the secondary turbocharger 50 During this period, the supercharging pressure (compressor pressure) by the secondary turbocharger 50 is contained, the supercharging pressure between the secondary turbocharger 50 and the intake control valve 55 rises abnormally, and the secondary turbocharger 50 Will cause surging and damage. For this reason, after the exhaust control valve 53 is fully opened, after the second set time has elapsed, even if the differential pressure DPS has not reached the intake control valve open differential pressure DPSST, the third set time given by T2 + TDP has elapsed. Thereafter, the intake control valve 55 is opened to prevent an abnormal increase in the supercharging pressure between the secondary turbocharger 50 and the intake control valve 55, and the secondary turbo associated with the failure of the differential pressure sensor 80 system. This prevents damage to the supercharger 50.
[0101]
The time chart of FIG. 16 shows the switching state from the single turbo mode to the twin turbo mode by the single-to-twin switching control described above.
[0102]
As described above, in the single to twin switching control, first, the supercharging pressure relief valve 57 is closed, the exhaust control valve 53 is opened, and the preliminary rotational speed of the secondary turbocharger 50 is increased. Thereafter, the time required to increase the preliminary rotational speed of the secondary turbocharger 50 is given by the exhaust control valve opening delay time T1, and the exhaust control valve 53 is fully opened after the delay time T1 has elapsed. Then, the supercharging pressure by the secondary turbocharger 50 between the blower 50b of the secondary turbocharger 50 and the intake control valve 55 increases and the differential pressure DPS increases, and after the exhaust control valve is fully opened, the intake control valve is opened. The delay time T2 compensates for the operation delay time until the exhaust control valve 53 is fully opened, and after the delay time T2, the differential pressure DPS between the upstream and downstream of the intake control valve 55 reaches the intake control valve open differential pressure DPSST. At that time, the intake control valve 55 is opened. Thereby, the switching from the single turbo state in which only the primary turbocharger 40 operates to the twin turbo state by the operation of both turbochargers 40 and 50 is smoothly performed, and the upstream pressure PU and the downstream of the intake control valve are further reduced. When the pressure PD becomes substantially equal, the intake control valve 55 is opened and supercharging from the secondary turbocharger 50 is started, so that the supercharging pressure generated when switching to the twin turbo state is temporarily increased. Generation of torque shock due to the reduction is effectively and reliably prevented.
[0103]
After the exhaust control valve 53 is fully opened (SOL.4 OFF → ON) and after the intake control valve opening delay time T2 (second set time) has elapsed, the differential pressure DPS between the upstream and downstream sides of the intake control valve 55 When the third set time by T2 + TDP has elapsed before reaching the intake control valve opening differential pressure DPSST, the intake control valve 55 is immediately opened (SOL.2 OFF → ON), and the differential pressure sensor 80 system By preventing an abnormal increase in the supercharging pressure between the secondary turbocharger 50 and the intake control valve 55 due to a failure, the secondary turbocharger 50 is prevented from being damaged in advance. When switching to the state, the reliability of the secondary turbocharger 50 is improved.
[0104]
Next, the twin turbo mode will be described.
[0105]
When the twin-turbo mode determination flag F1 is set due to the end of the single to twin switching control, or when the twin-turbo mode is in effect at the time of the previous routine execution, the process branches from step S101 to step S160 due to F1 = 1 when the current routine is executed. .
[0106]
Then, in step S160, the turbo switching determination value table is referred to with interpolation calculation based on the engine speed N to set the twin-to-single switching determination value TP1 (see FIG. 10), and the process proceeds to step S161, where the engine load TP and The twin-to-single switching judgment value TP1 is compared. If TP> TP1, the current operation area is in the twin turbo area, so the judgment value search flag F4 is cleared in step S162, and the single turbo area is entered in step S163. After clearing the single turbo region duration count value C2 for counting the single turbo region duration after the transition, the process proceeds to step S164, and in step S164 to step S167, the boost pressure relief valve switching solenoid valve SOL. 1. Intake control valve switching solenoid valve SOL. 2, first and second exhaust control valve switching solenoid valve SOL. 3 and 4 are turned ON, the boost pressure relief valve 57 is closed, the intake control valve 55 and the exhaust control valve 53 are both fully opened, and the twin turbo mode determination flag F1 is set in step S168. After returning to S117 and clearing the control valve switching time count value C1, the routine is exited.
[0107]
Under the twin turbo mode, the secondary turbocharger 50 is fully operated in addition to the primary turbocharger 40 by closing the boost pressure relief valve 57 and fully opening the intake control valve 55 and the exhaust control valve 53. The turbocharger 40, 50 is in a twin turbo state due to the supercharging operation, the compressed air due to the supercharging of both the turbochargers 40, 50 is supplied to the intake system, and the turbochargers 40, 50 are supercharged. Depending on the output characteristics of the operation, a torque curve for a twin turbo with high shaft torque in a high speed range can be obtained.
[0108]
On the other hand, if it is determined in step S161 that TP ≦ TP1, that is, the current operation region has shifted to the single turbo region (see FIG. 10) at the boundary of the twin → single switching determination line L1, the process proceeds to step S170. With reference to the value of the value search flag F4, if F4 = 0, the process proceeds to step S171, and if F4 = 1, the process jumps to step S173.
[0109]
The determination value search flag F4 is cleared when the engine operating state is in the twin turbo region in the twin turbo mode and the engine load TP is separated from the twin → single switching determination line L1 (TP1) (step S162). Therefore, after TP ≦ TP1, the process proceeds to step S171 when the routine is executed for the first time, and the single turbo region duration determination value T4 is set by referring to the single turbo region duration determination value table with interpolation calculation based on the engine load TP. . This determination value T4 is a reference value for switching to the single turbo mode in which only the primary turbocharger 40 operates after a predetermined time has elapsed after the engine operating state has shifted from the twin turbo region to the single turbo region.
[0110]
FIG. 15 is a conceptual diagram of a single turbo region duration determination value table. The single turbo region duration determination value T4 set according to the engine load TP is set to, for example, a maximum of 2.3 sec and a minimum of 0.6 sec, and the smaller the value of the engine load TP is, the larger the value is. Is set. As a result, after the engine operating state shifts from the twin turbo region to the single turbo region, the time until switching from the twin turbo mode to the single turbo mode is accelerated as the engine load increases.
[0111]
Next, after the determination value search flag F4 is set in step S172, the process proceeds to step S173.
[0112]
Then, after counting up the single turbo region duration count value C2 in step S173, the determination value T4 is compared with the count value C2 in step S174. If C2 ≧ T4, the process proceeds to step S175, and the count value C2 is set. After clearing, the process returns to step S108, and the twin turbo mode is switched to the single turbo mode. As a result, each switching solenoid valve SOL. 1 to 4 are turned off, the boost pressure relief valve 57 is opened, and both the intake control valve 55 and the exhaust control valve 53 are closed, so that the primary turbocharger 40, 50 is operated from the twin turbo state. Only the turbocharger 40 is switched to the single turbo state.
[0113]
The switching state at this time is shown in a time chart as shown in FIG. As described above, the switching from the twin turbo mode to the single turbo mode is performed when the engine operation region shifts from the twin turbo region to the single turbo region (TP ≦ TP1) and the state continues for a set time (C2 ≧ T4). Therefore, unnecessary switching of the supercharger due to a temporary decrease in the engine speed N accompanying a shift of the transmission or the like is prevented in advance.
[0114]
Here, the single turbo region duration determination value T4 giving the set time is set to a shorter time as the value of the engine load TP is higher and the load is higher, and the switching to the single turbo state is accelerated. In other words, high torque is required during high engine load operation, but the single turbo region side of the twin → single switching judgment line L1 has a shaft torque for single turbo rather than the torque given by the shaft torque curve for twin turbo. The torque given by the curve is higher, and if the twin turbo state is maintained in this region, sufficient shaft torque cannot be obtained, the output performance deteriorates, and the reacceleration performance also deteriorates. For this reason, when the engine is heavily loaded, the single turbo region duration determination value T4 is set to a short value, so that the switching from the twin turbo state to the single turbo state is speeded up, and the torque in the twin turbo state is low. By quickly switching to a single-turbo state with a high torque with a minimum operation in the region, the output performance is improved and the reacceleration performance is also improved.
[0115]
During low-load operation, the torque is low and the torque difference between the twin turbo and single turbo is small. Even if the set time is given enough to switch from the twin turbo to the single turbo, the torque fluctuations Hardly occurs. For this reason, when the load is low, the engine operating region shifts from the twin turbo region side to the single turbo region with the twin → single switching determination line L1 as a boundary, and the state is given by the single turbo region duration determination value T4. By switching from the twin turbo state to the single turbo state after the time has continued, unnecessary switching of the supercharger due to a temporary decrease in the engine speed N is effectively and reliably avoided.
[0116]
On the other hand, if C2 <T4 in step S174, the process returns to step S164, and the twin turbo state is maintained until the set time given by the determination value T4 elapses.
[0117]
Then, the value of the twin turbo mode determination flag F1 is referred to by an exhaust resistance variable muffler normal control subroutine (see FIG. 9) executed as normal control in the exhaust resistance variable muffler control routine shown in FIG. At present, it is determined whether the engine is in the twin turbo state or the single turbo state, and the exhaust control process for the exhaust resistance variable muffler 14 is performed so as to select the exhaust mode corresponding thereto.
[0118]
Next, an exhaust control process for the exhaust resistance variable muffler 14 will be described with reference to FIGS. The exhaust resistance variable muffler control routine shown in FIG. 8 is executed every set time (for example, 10 msec). First, in steps S201 and S202, the ON / OFF state of the test mode switch 120 and the read memory switch 121 is determined. It is determined whether the normal operation mode is selected or the test mode is selected.
[0119]
Then, when the test mode switch 120 or the read memory switch 121 is OFF (connector release state), it is determined that the normal operation mode is selected, and the routine jumps from the corresponding step to step S207 to perform normal control. When both switches 120 and 121 are ON (connector connection state), it is determined that the test mode is selected, and the process proceeds to step S203. In step S203 through step S206, the condition determination when executing the test mode, that is, the vehicle It is determined whether or not the vehicle is in an idle state while stopped.
[0120]
In step S203, it is determined whether or not the vehicle is stopped (VSP = 0) based on the vehicle speed VSP. If the vehicle is stopped with VSP = 0, it is determined in step S204 whether the throttle valve is fully closed when the idle switch 85b is ON. To do.
[0121]
When the idle switch 85b is in the fully closed throttle valve state, it is further determined in step S205 whether the neutral switch 93 is in the neutral state of the transmission, and when in the neutral state, the process proceeds to step S206, and the current engine The engine speed N is read, and it is determined whether the engine is in the idling engine speed state based on whether the engine speed N is within a set range (for example, within a range of 600 rpm to 1000 rpm).
[0122]
Then, only when it is in the idling rotation state, that is, when it is determined that the vehicle is idling while the vehicle is stopped by the determination in step S203 to step S206, the process proceeds to step S210, and the exhaust gas is exhausted every predetermined time by the processing after step S210. Test mode control for forcibly opening and closing the valve 103 of the variable resistance muffler 14 is executed.
[0123]
On the other hand, in steps S203, S204, S205, and S206, when VSP is not 0 and the vehicle is traveling, or when the idle switch 85b is OFF and non-idle, or when the neutral switch 93 is OFF and non-neutral, or when the engine is not idle. Since the test mode execution condition is not satisfied, the process proceeds from the corresponding step to step S207 to execute the normal time control.
[0124]
First, the normal control will be described prior to the test mode control. In step S207, the exhaust resistance variable muffler normal control subroutine shown in FIG. 9 is executed, and only the primary turbocharger 40 in the low speed range described above is executed. The valve 103 of the exhaust resistance variable muffler 14 corresponds to the single turbo mode in which the supercharging operation is performed and the twin turbo mode in which the turbochargers 40 and 50 are supercharged in the high speed range when the exhaust gas flow rate is low in the single turbo state. Is closed to set an exhaust mode with a large exhaust resistance, and when the exhaust gas flow rate is high in a twin turbo state, the valve 103 is opened to set an exhaust mode with a low exhaust resistance.
[0125]
In this exhaust resistance variable muffler normal time control subroutine, in step S220, the turbo mode determination flag F1 set in the turbo switching control routine described above is referred to, and only the primary turbocharger 40 in the single turbo mode with F1 = 0. In the single turbo state in which the turbocharger is supercharged, the process proceeds to step S221, the output signal state for the ACTR 106 is determined, and when the ON signal is being output (GACTR = ON), the ON signal output is maintained and the process jumps to step S226. After the transition from the single turbo mode to the twin turbo mode, clear the high load duration count value TMF2 for measuring the duration in the high load operation region with a high exhaust gas flow rate. Proceed to step S208.
[0126]
Immediately after the engine is started, it is in a single turbo state in which only the primary turbocharger 40 is supercharged by the single turbo mode, and the valve 103 of the exhaust resistance variable muffler 14 is closed by the above-described initialization routine. While the state continues, the valve 103 is kept closed.
[0127]
In step S221, when the output signal state for the ACTR 106 is OFF (GACTR = OFF), it is a transition from the twin turbo mode to the single turbo mode, and the valve 103 of the exhaust resistance variable muffler 14 is open. Since the exhaust mode with the low exhaust resistance is selected, the process proceeds to step S222, and the valve 103 of the exhaust resistance variable muffler 14 is closed.
[0128]
In step S222, the single turbo mode duration count value TMF1 for measuring the duration time of the single turbo mode after the transition from the twin turbo mode to the single turbo mode, and a preset valve closing delay time TCL (for example, a value corresponding to 3 sec) are obtained. In comparison, after shifting from the twin turbo mode to the single turbo mode, the single turbo mode is continued and it is determined whether the valve closing delay time TCL has elapsed. If TMF1 <TCL, the process proceeds to step S223, where the single turbo mode When the duration count value TMF1 is incremented and the process proceeds to step S208 via step S226 described above, after the transition from the twin turbo mode to the single turbo mode with TMF1 ≧ TCL, the valve remains in the single turbo mode and the valve closing delay time TCL has elapsed. Step S2 Proceed to step 24, and the output signal for ACTR 106 is turned ON.
[0129]
As a result, the output signal from the ECU 150 to the ACTR 106 is switched from OFF to ON, and from the ACTR 106 to the actuator motor 105 via the valve closing signal line, as shown in FIG. In response to this, the actuator motor 105 rotates forward, and the valve 103 of the exhaust resistance variable muffler 14 is closed by the urging force of the spring 103 a provided along with the valve 103.
[0130]
In step S225, the single turbo mode duration count value TMF1 is cleared, and the process proceeds to step S208 of the exhaust resistance variable muffler control routine through step S226.
[0131]
The relationship between the switching from the twin turbo mode to the single turbo mode and the switching of the exhaust mode by the above exhaust control will be described with reference to the time chart of FIG.
[0132]
When a transition is made from the twin turbo mode in which the primary turbocharger 40 and the secondary turbocharger 50 are both supercharged to the single turbo mode in which only the primary turbocharger 40 is supercharged, the twin turbo mode determination flag F1 is set. Clearing (F1 = 0) from the set (F1 = 1) starts the time measurement of the duration time of the single turbo mode. After the transition from the twin turbo mode to the single turbo mode, when the single turbo mode for operating only the primary turbocharger 40 continues for a set time determined by the valve closing delay time TCL, the valve 103 of the exhaust resistance variable muffler 14 Is closed, the occurrence of turbo lag is prevented, and even when the engine speed and the engine load change greatly instantaneously, such as when the transmission is shifting, the variable exhaust resistance muffler 14 The valve 103 is prevented from being closed unnecessarily, and the opening / closing hunting of the valve 103 can be reliably prevented.
[0133]
When the exhaust gas flow rate is low in the low speed region, the operation of the secondary turbocharger 50 is stopped in the single turbo mode, and exhaust gas is supplied to the primary turbocharger 40 in a concentrated manner, so that the primary turbocharger 40 The flow rate of the exhaust gas flowing through the turbine 40a is increased to ensure a high supercharging pressure even in a single turbo state, and at the time of a low exhaust gas flow rate in a single turbo state where only the primary turbocharger 40 operates. By closing the valve 103 of the exhaust resistance variable muffler 14 and closing the tail pipe 102a to enter the exhaust mode with a large exhaust resistance, the exhaust resistance variable muffler 14 is promoted to expand when the exhaust gas flow rate is small. High torque can be secured while enhancing the silencing effect.
[0134]
On the other hand, in step S220, in the twin turbo mode where both turbochargers 40 and 50 are supercharged in the twin turbo mode with F1 = 1, the process branches to step S227 to determine the output signal state for ACTR 106 and to ACTR 106. When the output signal state is ON (GACTR = ON), it is a transition from the single turbo mode to the twin turbo mode, and the exhaust mode with a large exhaust resistance when the valve 103 of the exhaust resistance variable muffler 14 is closed. Because of this state, the process proceeds to step S228, where the valve 103 of the exhaust resistance variable muffler 14 is opened.
[0135]
In step S228, the engine load Tp is compared with a set value TpMFH for determining whether the engine load is in the high load range of the exhaust gas high flow rate. When Tp <TpMFH, the process jumps to step S232, and in steps S232 and S233, The high load duration count value TMF2 and the single turbo mode duration count value TMF1 are cleared, respectively, and the routine proceeds to step S208 of the exhaust resistance variable muffler control routine.
[0136]
Further, when Tp ≧ TpMFH and the operation region is a high load region with a high exhaust gas flow rate, the process proceeds to step S229, and after the transition from the single turbo mode to the twin turbo mode, the high load for measuring the duration of operation in the high load region. The duration count value TMF2 is compared with a preset valve opening delay time TOP (equivalent to a value of 3 sec, for example), and after the transition from the single turbo mode to the twin turbo mode, the high exhaust gas flow rate is high under the twin turbo mode. It is determined whether or not the valve opening delay time TOP has elapsed by continuing the load operation. When TMF2 <TOP, the process proceeds to step S230, and the high load duration time count value TMF2 is counted up, and then step S233 is performed. Proceed to S208 and switch from single turbo mode to twin turbo mode with TMF2 ≧ TOP, then twin When the duration of the high load operation under Bomodo has passed the valve opening delay time TOP, the process proceeds to step S231, and turns OFF the output signal for ACTR106 (GACTR ← OFF).
[0137]
As a result, the output signal from the ECU 150 to the ACTR 106 is switched from ON to OFF, and from the ACTR 106 to the actuator motor 105 via the valve opening signal line, as shown in FIG. In response to this, the actuator motor 105 reversely rotates and the valve 103 of the exhaust resistance variable muffler 14 opens against the urging force of the spring 103a attached to the valve 103.
[0138]
Then, after steps S232 and S233, the process proceeds to step S208 of the exhaust resistance variable muffler control routine.
[0139]
When the twin turbo mode is continued and the output signal to the ACTR 106 is turned OFF by the above processing, the step jumps from step S227 to step S233 due to GACTR = OFF in step S227, and the exhaust resistance variable muffler control routine step Proceeding to S208, the valve 103 of the exhaust resistance variable muffler 14 is kept open.
[0140]
The relationship between the switching from the single turbo mode to the twin turbo mode and the switching of the exhaust mode by the above exhaust control will be described with reference to the time chart of FIG.
[0141]
When the single turbo mode in which only the primary turbocharger 40 is supercharged is switched to the twin turbo mode in which the primary turbocharger 40 and the secondary turbocharger 50 are both supercharged, the twin turbo mode determination flag F1 is set. It is set (F1 = 1) from the clear (F1 = 0), and the duration of the high load operation with the high exhaust gas flow rate in the twin turbo mode state is measured. After the transition from the single turbo mode to the twin turbo mode, the duration time of the high load operation in the twin turbo mode in which both turbochargers 40 and 50 are supercharged has passed the set time due to the valve opening delay time TOP. When this is done, the valve 103 of the exhaust resistance variable muffler 14 is opened, and a high output is required in a twin turbo state where both turbochargers 40, 50 are supercharged, and When the exhaust gas is determined to have a high flow rate, that is, when the valve 103 of the exhaust resistance variable muffler 14 is opened when it is truly necessary, and when the engine speed changes instantaneously, such as when the engine is idling. Even in this case, the valve 103 of the exhaust resistance variable muffler 14 is prevented from being opened unnecessarily. It is possible to reliably prevented.
[0142]
When the exhaust gas flow rate is high in a twin turbo state where both the primary turbocharger 40 and the secondary turbocharger 50 are supercharged in the high speed range, the valve 103 of the exhaust resistance variable muffler 14 is opened. By opening the tail pipe 102a and setting the exhaust mode with a low exhaust resistance, the exhaust resistance is reduced and the exhaust efficiency is improved in response to the increase in the exhaust gas flow rate at this time, and the engine output is increased by the twin turbo. It becomes possible to cope with.
[0143]
When the routine proceeds to step S208 of the exhaust resistance variable muffler control routine from the exhaust resistance variable muffler normal time control subroutine, in steps S208 and S209, the valve closing duration of the valve 103 of the exhaust resistance variable muffler 14 in the test mode is set. , The valve opening continuation time, that is, the ON continuation time count value TMFT1 and the OFF continuation time count value TMFT2 for measuring the ON continuation time and the OFF continuation time of the output signal to the ACTR 106 are cleared, and the routine is exited.
[0144]
Next, the test mode control will be described. In steps S201 and S202, it is determined that the test mode switch 120 and the read memory switch 121 are both ON and the test mode is selected, and the determination in steps S203 to S206. Therefore, only when it is determined that the vehicle is idling while the vehicle is stopped, the process proceeds to step S210, and the valve 103 of the exhaust resistance variable muffler 14 is forcibly opened and closed every predetermined time by the processing after step S210.
[0145]
First, in step S210, the output signal state for the ACTR 106 is determined. When it is determined that the valve 103 of the exhaust resistance variable muffler 14 is closed while the ON signal is being output (GACTR = ON), the process proceeds to step S211. The ON duration count value TMFT1 for measuring the ON duration of the output signal to the ACTR 106 is compared with a preset valve closing duration TTEST1 (for example, a value corresponding to 2 to 5 sec), and the duration of the ON signal for the ACTR 106, ie, After the valve 103 of the exhaust resistance variable muffler 14 is closed, it is determined whether or not the valve closing duration has reached the valve closing duration TTEST1, and if TMFT1 <TTEST1, the process proceeds to step S212 and the ON duration time is counted. The value TMFT1 is counted up, the routine is exited, and exhaust resistance variable muffler with TMFT1 ≧ TTEST1 When the valve closing duration of the 14th valve 103 reaches the valve closing duration TTEST1, the process proceeds to step S213, and the output signal to the ACTR 106 is turned OFF.
[0146]
As a result, the output signal from the ECU 150 to the ACTR 106 is switched from ON to OFF, and from the ACTR 106 to the actuator motor 105 via the valve opening signal line, as shown in FIG. In response to this, the actuator motor 105 rotates in reverse, and the valve 103 of the exhaust resistance variable muffler 14 opens against the urging force of the spring 103 a provided in the valve 103.
[0147]
Therefore, the valve 103 of the exhaust resistance variable muffler 14 is forcibly opened after continuing the closed state for a set time determined by the valve closing duration TTEST1.
[0148]
In step S214, the ON duration count value TMFT1 is cleared and the routine is exited.
[0149]
On the other hand, when it is determined in step S210 that the output signal state for the ACTR 106 is OFF (GACTR = OFF) and the valve 103 of the exhaust resistance variable muffler 14 is open, the process branches to step S215 and The OFF duration count value TMFT2 for measuring the OFF duration of the output signal is compared with a preset valve opening duration TTEST2 (for example, a value corresponding to 2 to 5 sec), and the duration of the OFF signal for the ACTR 106, that is, the exhaust resistance After the valve 103 of the variable muffler 14 is opened, it is determined whether or not the valve opening duration has reached the valve opening duration TTEST2. If TMFT2 <TTEST2, the OFF duration count value TMFT2 is counted in step S216. Up the routine and exhaust resistance variable muffler with TMFT2 ≧ TTEST2 When the valve opening continuation time of the 14th valve 103 reaches the valve opening continuation time TTEST1, the process proceeds to step S217, and the output signal to the ACTR 106 is turned ON.
[0150]
As a result, the output signal from the ECU 150 to the ACTR 106 is switched from OFF to ON, and from the ACTR 106 to the actuator motor 105 via the valve closing signal line, as shown in FIG. In response to this, the actuator motor 105 rotates forward, and the valve 103 of the exhaust resistance variable muffler 14 is closed by the urging force of the spring 103 a provided along with the valve 103.
[0151]
Therefore, the valve 103 of the exhaust resistance variable muffler 14 is forcibly closed after continuing the valve opening state for a set time determined by the valve opening continuation time TTEST2.
[0152]
In step S218, the OFF duration count value TMFT2 is cleared and the routine is exited.
[0153]
In this way, during the test mode control, as shown in the time chart of FIG. 19, the output signal state from the ECU 150 to the ACTR 106 is ON at every set time determined by the valve closing duration TTEST1 and the valve opening duration TTEST2. The valve 103 of the exhaust resistance variable muffler 14 is forcibly opened and closed.
[0154]
Here, if the valve 103, the wire 104, the actuator motor 105, the ACTR 106, etc. are normal when the test mode is selected, the valve 103 of the exhaust resistance variable muffler 14 is set at every set time during idling while the vehicle is stopped. The valve 103 and the wire 104 can be easily opened and closed, and the normal operation can be confirmed visually.
[0155]
Also, when the test mode is selected and the valve 103 is not operated despite idling while the vehicle is stopped, the valve 103 is stuck, the wire 104 is caught, or the actuator motor 105, the ACTR 106 is broken, or the ECU 150 This is a failure such as disconnection or short circuit of any signal line from the ACTR 106 and the ACTR 106 to the actuator motor 105, and the operator can easily determine this.
[0156]
Since the test mode is executed when the vehicle is in an idle state, the engine operability and the superchargers 40, 50, etc. are not affected even when the valve 103 of the exhaust resistance variable muffler 14 is forcibly opened and closed. Does not adversely affect. Even if the vehicle is run in the test mode selection state, the test mode is not executed, and the valve 103 of the exhaust resistance variable muffler 14 is forcibly opened and closed every predetermined time while the vehicle is running. In other words, the engine operability is not deteriorated by increasing or decreasing the exhaust resistance in a short time, and the turbochargers 40 and 50 are not adversely affected.
[0157]
Although one embodiment of the present invention has been described above, the present invention is not limited to this, and an engine load other than the basic fuel injection pulse width TP may be used. It can also be applied to engines other than horizontally opposed engines. In addition, the exhaust resistance variable muffler operation confirmation device according to the present invention can be applied even to an exhaust resistance variable muffler attached to the exhaust system of a naturally aspirated engine. It is not limited to the form.
[0158]
  Furthermore, in this embodiment, a test mode switch and a read memory switch are adopted as mode switching means, and the test mode is selected when both switches are ON. However, at least one of the switches is ON. The test mode may be selected or the mode may be switched with one switch.TheThe mode switching means is not limited to this embodiment, and various types are employed.
[0159]
【The invention's effect】
  As explained aboveAccording to the present invention, when the normal operation mode is selected by the mode switching means, when the exhaust gas flow rate is low, the exhaust resistance variable muffler valve is closed to set the exhaust mode with a large exhaust resistance, and when the exhaust gas flow rate is high, the exhaust resistance is reduced. When the variable muffler valve is opened to enter the normal operation state where the exhaust resistance is low, and when the test mode for checking the valve operation is selected by the mode switching means, the preset condition is When established, a test mode state in which the exhaust resistance variable muffler valve is forcibly opened and closed is entered. For example, when the set condition is satisfied, the valve of the variable exhaust resistance type muffler opens and closes, and the valve and the operation of the valve can be easily performed. When the test mode is selected and the set conditions are satisfied, the exhaust resistance variable muffler valve does not operate. Therefore, by selecting the test mode, it is possible to easily confirm whether the exhaust resistance variable muffler valve is stuck or the valve operating system is faulty.
  At that time, if the set condition is set to idle when the vehicle is stopped, even if the exhaust resistance variable muffler valve is forcibly opened and closed by the test mode, it will have no adverse effect on the engine operability and each turbocharger. Even if the vehicle is run with the test mode selected, the test mode is not executed, and the exhaust resistance variable muffler valve is forcibly opened and closed while the vehicle is running. In other words, the engine operability is not deteriorated due to the increase or decrease of the exhaust resistance in a short time, and the turbochargers and the like are not adversely affected. Further, when the test mode is selected, the valve is forcibly opened and closed at set time intervals, so that the operation of the valve can be easily visually confirmed, and the normal operation can be confirmed visually.
[Brief description of the drawings]
FIG. 1 is a basic configuration diagram of the present invention.
FIG. 2 is a flowchart showing an initialization routine.
FIG. 3 is a flowchart showing a turbo switching control routine.
FIG. 4 is a flowchart showing a turbo switching control routine (continued).
FIG. 5 is a flowchart showing a turbo switching control routine (continued).
FIG. 6 is a flowchart showing a turbo switching control routine (continued).
FIG. 7 is a flowchart showing a turbo switching control routine (continued).
FIG. 8 is a flowchart showing an exhaust resistance variable muffler control routine.
FIG. 9 is a flowchart showing an exhaust resistance variable muffler normal time control subroutine;
FIG. 10 is an explanatory diagram showing each switching determination value and the relationship between a single turbo region and a twin turbo region.
FIG. 11 is an explanatory diagram of an exhaust control valve small opening control region.
FIG. 12 is a conceptual diagram of an exhaust control valve opening delay time setting table.
FIG. 13 is a conceptual diagram of an intake control valve opening delay time setting table.
FIG. 14 is a conceptual diagram of an intake control valve opening differential pressure setting table.
FIG. 15 is a conceptual diagram of a single turbo region duration determination value table.
FIG. 16 is a time chart showing the relationship between the switching state from the single turbo mode to the twin turbo mode by the supercharger switching control and the switching state of the exhaust mode by the exhaust control;
FIG. 17 is a time chart showing the relationship between the switching state from the twin turbo mode to the single turbo mode by the supercharger switching control and the switching state of the exhaust mode by the exhaust control.
FIG. 18 is a time chart showing the relationship between each signal state in the normal operation mode and the operation state of the valve of the exhaust resistance variable muffler.
FIG. 19 is a time chart showing the relationship between each signal state in the test mode and the valve operating state of the exhaust resistance variable muffler.
FIG. 20 is an overall schematic view of a supercharged engine.
FIG. 21 is a block diagram of an exhaust resistance variable muffler and a valve operating system.
FIG. 22 is an explanatory view showing a mounting state of the exhaust resistance variable muffler on the vehicle.
FIG. 23 is an explanatory diagram of an exhaust mode of a variable exhaust resistance type muffler.
FIG. 24 is a circuit configuration diagram of an electronic control system.
[Explanation of symbols]
14 Exhaust resistance variable muffler
40 Primary turbocharger
50 Secondary turbocharger
53 Exhaust control valve
55 Intake control valve
103 Valve
120 test mode switch (mode switching means)
121 Read memory switch (mode switching means)
150 Electronic control unit (ECU)
160 Main computer
Tp Basic fuel injection pulse width (engine load)
TpMFH setting value
TOP Valve opening delay time (set time)
TCL valve closing delay time (set time)

Claims (3)

The exhaust system of the engine is equipped with an exhaust resistance variable muffler that has multiple exhaust modes with different exhaust resistance, and when the exhaust gas flow rate is low, the exhaust resistance variable muffler valve is closed to provide an exhaust mode with high exhaust resistance. In the exhaust resistance variable muffler operation confirmation device that opens the exhaust resistance variable muffler valve at the gas flow rate to make the exhaust mode with a small exhaust resistance,
Mode switching means for switching between a normal operation mode in a normal operation state and a test mode for confirming the operation of the valve;
Checking the operation of the variable exhaust resistance muffler, comprising forcibly opening and closing means for forcibly opening and closing the valve of the variable exhaust resistance muffler when a preset condition is satisfied when the test mode is selected apparatus. 2. The exhaust resistance variable muffler operation confirmation device according to claim 1, wherein the setting condition is an idling time while the vehicle is stopped . 3. The exhaust resistance variable muffler operation confirmation device according to claim 1, wherein when the test mode is selected, the valve is forcibly opened and closed at a set time .

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