JP4867687B2 - INTERNAL COMBUSTION ENGINE DEVICE, ITS CONTROL METHOD, AND VEHICLE - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the starting characteristics of an internal-combustion engine when it is restarted. <P>SOLUTION: When the operation stop conditions are established (S130) where the ignition is put off and the temperature Tw of the engine cooling water is below the reference value Tref, the first motor is controlled so that the engine is put in motoring at the prescribed engine speed Nidl for a prescribed period of time in the condition that the fuel to engine is cut off (S140, S150). Thereupon a VVT motor able to operate only while an intake cam shaft is rotating in association with the rotation of a crank shaft of the engine is put in the operable condition, and the VVT motor is operated so that the opening/closing timing VT of a suction valve is altered toward the most delayed angle timing VT1 (S110). This reduces the energy required to make the compression stroke when the engine is started next, so that the starting characteristics when the engine is restarted can be enhanced. <P>COPYRIGHT: (C)2008,JPO&amp;INPIT

Description

  The present invention relates to an internal combustion engine device, a control method therefor, and a vehicle.

Conventionally, as this type of internal combustion engine apparatus, an apparatus having an engine having a variable valve timing mechanism for changing the opening / closing timing of an intake valve and a motor for motoring the engine has been proposed (for example, see Patent Document 1). ). In this device, when stopping the engine idling, the intake valve opening / closing timing is set to the most retarded timing after increasing the negative pressure of the intake pipe pressure while the engine is motored at a predetermined speed. Thus, an increase in the pressure in the cylinder is suppressed to reduce vibrations that occur when the engine is stopped.
JP 2001-304005 A

  In the internal combustion engine device described above, there is a case where the opening / closing timing of the intake valve is controlled to be the most retarded timing when the engine is stopped for the purpose of improving startability when the engine is next started. In this case, in a device that changes the phase of the camshaft using hydraulic pressure or the like, the intake valve may be set to the most retarded timing by using the hydraulic pressure held by the actuator even after the engine is stopped. However, in a device that changes the phase of the camshaft using an electric motor or the like, an electric motor with a large physique is required due to the driving force required to change the phase of the camshaft that has stopped rotating. It is desirable to set the most retarded timing while the shaft is rotating. In particular, when the system is turned off, if the engine is not stopped immediately, the driver will feel uncomfortable, so that it is possible to change the opening / closing timing before stopping the operation at the time of idling stop. There may be a case where sufficient time for controlling the opening / closing timing cannot be secured.

  The internal combustion engine device, the control method thereof, and the vehicle according to the present invention are intended to improve the startability when the internal combustion engine is next started.

  The internal combustion engine device, the control method thereof, and the vehicle of the present invention employ the following means in order to achieve the above object.

The internal combustion engine device of the present invention is
An internal combustion engine device having an internal combustion engine,
A cam mechanism that is mechanically connected to the output shaft of the internal combustion engine and rotates with the rotation of the output shaft to open and close the intake valve of the internal combustion engine, and can be driven only when the cam mechanism is driven. An intake valve that opens and closes the intake valve so as to change an opening / closing timing with respect to the rotation of the output shaft, and a mechanism driving unit that drives the cam mechanism to change a phase angle of the cam mechanism with respect to the output shaft. Opening and closing means;
Motoring means for motoring the internal combustion engine;
When the predetermined operation stop condition is satisfied, the internal combustion engine and the motoring means are controlled so that the internal combustion engine is motored for a predetermined time at a predetermined rotation speed with fuel injection stopped. In order to improve the startability of the next internal combustion engine while the cam mechanism is being driven, the intake valve opening / closing is changed so that the opening / closing timing of the intake valve is changed to the slowest timing within the changeable range. Stop-time control means for controlling the means;
It is a summary to provide.

  In the internal combustion engine device of the present invention, when a predetermined operation stop condition is satisfied, the internal combustion engine and the motoring means are operated so that the internal combustion engine is motored for a predetermined time at a predetermined rotation speed with the fuel injection stopped. The engine is mechanically connected to the output shaft of the internal combustion engine and rotated with the rotation of the output shaft to drive the cam mechanism that opens and closes the intake valve of the internal combustion engine. In order to improve the performance, the intake valve opening / closing timing can be driven only when the cam mechanism is driven so as to be changed toward the slowest timing within the changeable range, and the phase angle with respect to the output shaft of the cam mechanism In order to change this, the intake valve opening / closing means having a mechanism driving section for driving the cam mechanism and the cam mechanism is controlled. Here, the control is performed so that the opening / closing timing of the intake valve is changed to the latest timing within the changeable range by reducing the energy required for the compression process when the internal combustion engine is next started. This is based on the fact that the startability can be improved. As described above, when the predetermined operation stop condition is satisfied, the internal combustion engine is motored, so that the mechanism drive unit that can be driven only when the cam mechanism is driven can be driven. The valve opening / closing timing can be changed toward the slowest timing within a changeable range. As a result, the startability when the internal combustion engine is started next can be improved.

  In such an internal combustion engine device of the present invention, the predetermined operation stop condition may be a condition including a condition for stopping the operation of the internal combustion engine when the system is turned off. In this case, the predetermined operation stop condition may be a condition including a condition that an engine temperature reflecting physical quantity that is a physical quantity reflecting the temperature of the internal combustion engine is less than a predetermined quantity. This is based on the fact that the smaller the engine temperature reflecting physical quantity when the fuel injection to the internal combustion engine is stopped, the faster the rotational speed of the internal combustion engine decreases. Here, the engine temperature reflecting physical quantity includes, for example, the temperature of the cooling water of the internal combustion engine and the temperature of the lubricating oil.

  Further, in the internal combustion engine device of the present invention, the stop time control means stops the control of the intake valve opening / closing means when the rotational speed of the internal combustion engine reaches a stop rotational speed smaller than the predetermined rotational speed. It can also be assumed. In this way, after the internal combustion engine is motored, the control of the intake valve opening / closing means is continued until the rotational speed of the internal combustion engine reaches the stop rotational speed. It can be changed more reliably toward the timing. As a result, the startability when the internal combustion engine is started next time can be improved. Even after the internal combustion engine is motored, the intake valve opening and closing timing is the slowest within the range that can be changed, but when the internal combustion engine speed reaches the stopping rotational speed, the intake valve opening and closing timing is Since the control of the means is stopped, it is possible to prevent the cam mechanism from being driven more than necessary by the mechanism driving portion of the intake valve opening / closing means.

  In the internal combustion engine device of the present invention in which the control of the intake valve opening / closing means is stopped when the rotational speed of the internal combustion engine reaches a stop rotational speed smaller than the predetermined rotational speed, the stop rotational speed is the predetermined rotational speed. The engine speed is lower than the engine speed at which the control of the intake valve opening / closing means is stopped when the operation of the internal combustion engine is stopped due to the operation stop condition when the internal combustion engine is intermittently operated. You can also In this way, when the operation stop condition for intermittent operation of the internal combustion engine is satisfied, the cam mechanism is more driven by the mechanism drive unit of the intake valve opening / closing means than when the predetermined operation stop condition is satisfied. You can stop early.

  In the internal combustion engine device of the present invention, the mechanism drive unit may be a drive unit including an electric motor as a drive source.

  The vehicle of the present invention is the internal combustion engine apparatus of the present invention according to any one of the above-described aspects, that is, basically an internal combustion engine apparatus having an internal combustion engine, which is mechanically coupled to the output shaft of the internal combustion engine. A cam mechanism that rotates with the rotation of the output shaft to open and close the intake valve of the internal combustion engine, and can be driven only when the cam mechanism is driven, and changes a phase angle of the cam mechanism with respect to the output shaft. An intake valve opening / closing means for opening and closing the intake valve so that the opening / closing timing with respect to the rotation of the output shaft can be changed, and a motoring means for motoring the internal combustion engine. And when the predetermined operation stop condition is satisfied, the internal combustion engine and the motoring means are operated so that the internal combustion engine is motored for a predetermined time at a predetermined rotation speed with fuel injection stopped. In order to improve the startability of the next internal combustion engine while the cam mechanism is being driven, the intake valve opening / closing operation is performed so that the intake valve opening / closing timing becomes the slowest within a changeable range. A gist of the invention is that an internal combustion engine device including a stop time control means for controlling the means is mounted and travels using power from the internal combustion engine.

  According to the vehicle of the present invention, since the internal combustion engine device of the present invention according to any one of the above-described aspects is mounted, the effects exhibited by the internal combustion engine device of the present invention, for example, startability when the internal combustion engine is started next time. It is possible to achieve the same effects as the effect that can be improved, the effect that the cam drive mechanism can be prevented from being driven more than necessary by the mechanism drive portion of the intake valve opening / closing means, and the like.

The control method of the internal combustion engine device of the present invention includes:
A cam mechanism that is mechanically coupled to an output shaft of the internal combustion engine and rotates with the rotation of the output shaft to open and close the intake valve of the internal combustion engine; and the cam mechanism is driven A mechanism drive unit that drives the cam mechanism to change the phase angle of the cam mechanism with respect to the output shaft, and opens and closes the intake valve so that the opening / closing timing with respect to the rotation of the output shaft can be changed. A control method for an internal combustion engine device comprising: an intake valve opening / closing means for performing; and a motoring means for motoring the internal combustion engine,
When the predetermined operation stop condition is satisfied, the internal combustion engine and the motoring means are controlled so that the internal combustion engine is motored for a predetermined time at a predetermined rotation speed with fuel injection stopped. In order to improve the startability of the next internal combustion engine while the cam mechanism is being driven, the intake valve opening / closing is changed so that the opening / closing timing of the intake valve is changed to the slowest timing within the changeable range. Control means,
It is characterized by that.

  In the control method for an internal combustion engine device according to the present invention, when a predetermined operation stop condition is satisfied, the internal combustion engine is motored for a predetermined time at a predetermined rotation speed with the fuel injection stopped. While the cam mechanism that controls the motoring means and is mechanically connected to the output shaft of the internal combustion engine and rotates with the rotation of the output shaft to open and close the intake valve of the internal combustion engine is driven, the next internal combustion engine The output shaft of the cam mechanism can be driven only when the cam mechanism is driven so that the opening / closing timing of the intake valve is changed to the slowest timing in order to improve engine startability. In order to change the phase angle with respect to the intake valve, an intake valve opening / closing means having a mechanism driving portion for driving the cam mechanism and the cam mechanism is controlled. Here, the control is performed so that the opening / closing timing of the intake valve is changed to the latest timing within the changeable range by reducing the energy required for the compression process when the internal combustion engine is next started. This is based on the fact that the startability can be improved. As described above, when the predetermined operation stop condition is satisfied, the internal combustion engine is motored, so that the mechanism drive unit that can be driven only when the cam mechanism is driven can be driven. The valve opening / closing timing can be changed toward the slowest timing within a changeable range. As a result, the startability when the internal combustion engine is started next can be improved.

  Next, the best mode for carrying out the present invention will be described using examples.

  FIG. 1 is a configuration diagram showing an outline of the configuration of a hybrid vehicle 20 equipped with an internal combustion engine device as one embodiment of the present invention. As shown in the figure, the hybrid vehicle 20 of the embodiment includes an engine 22, a three-shaft power distribution / integration mechanism 30 connected to a crankshaft 26 as an output shaft of the engine 22 via a damper 28, and power distribution / integration. A motor MG1 capable of generating electricity connected to the mechanism 30, a reduction gear 35 attached to a ring gear shaft 32a as a drive shaft connected to the power distribution and integration mechanism 30, a motor MG2 connected to the reduction gear 35, And a hybrid electronic control unit 70 for controlling the entire apparatus.

  The engine 22 is configured as an internal combustion engine capable of outputting power using a hydrocarbon-based fuel such as gasoline or light oil, and the air purified by an air cleaner 122 is passed through a throttle valve 124 as shown in FIG. Inhaled and gasoline is injected from the fuel injection valve 126 to mix the sucked air and gasoline, and this mixture is sucked into the fuel chamber through the intake valve 128 and explosively burned by an electric spark from the spark plug 130. Thus, the reciprocating motion of the piston 132 pushed down by the energy is converted into the rotational motion of the crankshaft 26. Exhaust gas from the engine 22 is discharged to the outside air through a purification device (three-way catalyst) 134 that purifies harmful components such as carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NOx).

  The engine 22 also includes a variable valve timing mechanism 150 that can continuously change the opening / closing timing of the intake valve 128. As shown in FIG. 3, the variable valve timing mechanism 150 is integrated with an intake camshaft 152 for opening and closing the intake valve 128 and a cam sprocket connected to the crankshaft 26 via a timing chain. A movable portion 154 capable of changing the phase and a VVT (Variable Valve Timing) motor 156 as a DC brushless motor that drives the movable portion 154 are provided, and the phase of the intake camshaft 152 relative to the crankshaft 26 is driven by the VVT motor 156. The opening / closing timing of the intake valve 128 can be continuously changed by advancing or retarding the angle. Since the VVT motor 156 requires a large driving force to change the phase of the intake camshaft 152 that has stopped rotating, the intake camshaft 152 is rotating while the crankshaft 26 is rotating. Uses a physique that can only be driven. FIG. 4 shows an example of the opening / closing timing of the intake valve 128 when the angle of the intake camshaft 152 is advanced and the opening / closing timing of the intake valve 128 when the angle of the intake camshaft 152 is retarded. In the embodiment, the angle of the intake camshaft 152 at the opening / closing timing of the intake valve 128 where power is efficiently output from the engine 22 is used as a reference angle, and the angle of the intake camshaft 152 is advanced from the reference angle. The engine 22 can be in an operating state in which high torque can be output, and by reducing the angle of the intake camshaft 152 to the most retarded angle, the pressure fluctuation in the cylinder of the engine 22 can be reduced to stop or start the operation of the engine 22. It is comprised so that it can be set as the suitable driving | running state. Hereinafter, in the embodiment, the opening / closing timing of the intake valve 128 at which the angle of the intake camshaft 152 becomes the most retarded angle is referred to as the most retarded angle timing VT1.

  The engine 22 is controlled by an engine electronic control unit (hereinafter referred to as an engine ECU) 24. The engine ECU 24 is configured as a microprocessor centered on the CPU 24a, and includes a ROM 24b that stores a processing program, a RAM 24c that temporarily stores data, an input / output port and a communication port (not shown), in addition to the CPU 24a. . The engine ECU 24 includes signals from various sensors that detect the state of the engine 22, a crank position from the crank position sensor 140 that detects the rotational position of the crankshaft 26, and a water temperature sensor 142 that detects the temperature of cooling water in the engine 22. The cooling water temperature Tw from the cylinder, the in-cylinder pressure from the pressure sensor 143 attached to the combustion chamber, the intake camshaft 152 that opens and closes the intake valve 128 that performs intake and exhaust to the combustion chamber, and the rotational position of the exhaust camshaft that opens and closes the exhaust valve The cam position from the cam position sensor 144 for detecting the position, the throttle position from the throttle valve position sensor 146 for detecting the position of the throttle valve 124, and the air flow meter from the air flow meter 148 attached to the intake pipe No., an intake air temperature from a temperature sensor 149 attached to the intake pipe, the air-fuel ratio from an air-fuel ratio sensor 135a, such as oxygen signal from an oxygen sensor 135b is input via the input port. The engine ECU 24 also integrates various control signals for driving the engine 22, such as a drive signal to the fuel injection valve 126, a drive signal to the throttle motor 136 that adjusts the position of the throttle valve 124, and an igniter. The control signal to the ignition coil 138 and the drive signal to the VVT motor 156 of the variable valve timing mechanism 150 are output via the output port. The engine ECU 24 is in communication with the hybrid electronic control unit 70, controls the operation of the engine 22 by a control signal from the hybrid electronic control unit 70, and outputs data related to the operation state of the engine 22 as necessary. .

  The power distribution and integration mechanism 30 includes an external gear sun gear 31, an internal gear ring gear 32 arranged concentrically with the sun gear 31, a plurality of pinion gears 33 that mesh with the sun gear 31 and mesh with the ring gear 32, A planetary gear mechanism is provided that includes a carrier 34 that holds a plurality of pinion gears 33 so as to rotate and revolve, and that performs differential action using the sun gear 31, the ring gear 32, and the carrier 34 as rotational elements. In the power distribution and integration mechanism 30, the crankshaft 26 of the engine 22 is connected to the carrier 34, the motor MG1 is connected to the sun gear 31, and the reduction gear 35 is connected to the ring gear 32 via the ring gear shaft 32a. When functioning as a generator, power from the engine 22 input from the carrier 34 is distributed according to the gear ratio between the sun gear 31 side and the ring gear 32 side, and when the motor MG1 functions as an electric motor, the engine input from the carrier 34 The power from 22 and the power from the motor MG1 input from the sun gear 31 are integrated and output to the ring gear 32 side. The power output to the ring gear 32 is finally output from the ring gear shaft 32a to the drive wheels 63a and 63b of the vehicle via the gear mechanism 60 and the differential gear 62.

  The motor MG1 and the motor MG2 are both configured as well-known synchronous generator motors that can be driven as generators and can be driven as motors, and exchange power with the battery 50 via inverters 41 and 42. The power line 54 connecting the inverters 41 and 42 and the battery 50 is configured as a positive electrode bus and a negative electrode bus shared by the inverters 41 and 42, and the electric power generated by one of the motors MG1 and MG2 It can be consumed by a motor. Therefore, battery 50 is charged / discharged by electric power generated from one of motors MG1 and MG2 or insufficient electric power. If the balance of electric power is balanced by the motors MG1 and MG2, the battery 50 is not charged / discharged. The motors MG1 and MG2 are both driven and controlled by a motor electronic control unit (hereinafter referred to as a motor ECU) 40. The motor ECU 40 detects signals necessary for driving and controlling the motors MG1 and MG2, such as signals from rotational position detection sensors 43 and 44 that detect the rotational positions of the rotors of the motors MG1 and MG2, and current sensors (not shown). The phase current applied to the motors MG1 and MG2 to be applied is input, and a switching control signal to the inverters 41 and 42 is output from the motor ECU 40. The motor ECU 40 is in communication with the hybrid electronic control unit 70, controls the driving of the motors MG1 and MG2 by a control signal from the hybrid electronic control unit 70, and, if necessary, data on the operating state of the motors MG1 and MG2. Output to the hybrid electronic control unit 70.

  The battery 50 is managed by a battery electronic control unit (hereinafter referred to as a battery ECU) 52. The battery ECU 52 receives signals necessary for managing the battery 50, for example, a voltage between terminals from a voltage sensor (not shown) installed between terminals of the battery 50, and a power line 54 connected to the output terminal of the battery 50. The charging / discharging current from the attached current sensor (not shown), the battery temperature Tb from the temperature sensor 51 attached to the battery 50, and the like are input. Output to the control unit 70. The battery ECU 52 also calculates the remaining capacity (SOC) based on the integrated value of the charge / discharge current detected by the current sensor in order to manage the battery 50.

  The hybrid electronic control unit 70 is configured as a microprocessor centered on the CPU 72, and in addition to the CPU 72, a ROM 74 for storing processing programs, a RAM 76 for temporarily storing data, an input / output port and communication not shown. And a port. The hybrid electronic control unit 70 includes a shift position SP from the shift position sensor 82 that detects an ignition on (IGON) signal and an ignition off (IGOFF) signal from the ignition switch 80, an operation position of the shift lever 81, and an accelerator pedal 83. Accelerator opening degree Acc from the accelerator pedal position sensor 84 that detects the amount of depression of the vehicle, brake pedal position BP from the brake pedal position sensor 86 that detects the amount of depression of the brake pedal 85, vehicle speed V from the vehicle speed sensor 88, etc. are input ports. Is entered through. As described above, the hybrid electronic control unit 70 is connected to the engine ECU 24, the motor ECU 40, and the battery ECU 52 via the communication port, and exchanges various control signals and data with the engine ECU 24, the motor ECU 40, and the battery ECU 52. ing.

  The hybrid vehicle 20 of the embodiment thus configured calculates the required torque to be output to the ring gear shaft 32a as the drive shaft based on the accelerator opening Acc and the vehicle speed V corresponding to the depression amount of the accelerator pedal 83 by the driver. Then, the operation of the engine 22, the motor MG1, and the motor MG2 is controlled so that the required power corresponding to the required torque is output to the ring gear shaft 32a. As operation control of the engine 22, the motor MG1, and the motor MG2, the operation of the engine 22 is controlled so that power corresponding to the required power is output from the engine 22, and all of the power output from the engine 22 is the power distribution and integration mechanism 30. Torque conversion operation mode for driving and controlling the motor MG1 and the motor MG2 so that the torque is converted by the motor MG1 and the motor MG2 and output to the ring gear shaft 32a, and the required power and the power required for charging and discharging the battery 50. The engine 22 is operated and controlled so that suitable power is output from the engine 22, and all or part of the power output from the engine 22 with charging / discharging of the battery 50 is the power distribution and integration mechanism 30, the motor MG1, and the motor. The required power is converted to the ring gear shaft 32 with torque conversion by MG2. Charge / discharge operation mode in which the motor MG1 and the motor MG2 are driven and controlled to be output to each other, and a motor operation mode in which the operation of the engine 22 is stopped and the power corresponding to the required power from the motor MG2 is output to the ring gear shaft 32a. and so on. In the hybrid vehicle 20 according to the embodiment, during the operation in the torque conversion operation mode or the charge / discharge operation mode in which the engine 22 is operated, the condition that the required power required for the engine 22 is less than the threshold or the remaining battery 50 is remaining. When an automatic stop condition such as a condition that the capacity (SOC) is equal to or greater than a threshold value is satisfied, the engine 22 is stopped and the operation mode is switched from the motor MG2 to a motor operation mode that generates power corresponding to the required power. Further, when an automatic start condition such as a condition in which the vehicle speed V is less than the threshold value or a condition in which the remaining capacity (SOC) of the battery 50 is less than the threshold value is satisfied during the operation in the motor operation mode in which the engine 22 is stopped, the engine 22 is satisfied. Is started, and the operation mode is switched to the torque conversion operation mode or the charge / discharge operation mode. Thus, in the hybrid vehicle 20 of the embodiment, the intermittent operation of the engine 22 for starting or stopping the engine 22 is executed according to the operation state.

  Next, the operation of the hybrid vehicle 20 of the embodiment configured as described above, particularly the operation when stopping the operation of the engine 22 by the operation of the driver will be described. FIG. 4 is a flowchart showing an example of an IGOFF stop control routine executed by the hybrid electronic control unit 70. This routine is executed when an IGOFF signal is input from the ignition switch 80.

  When the IGOFF stop control routine is executed, the CPU 72 of the hybrid electronic control unit 70 first instructs the engine ECU 24 to cut the fuel of the engine 22 (step S100), and sets the opening / closing timing VT of the intake valve 128. A process of instructing driving of the VVT motor 156 to change toward the most retarded angle timing VT1 is executed (step S110). The engine ECU 24 that has received the instruction signal stops fuel injection and starts driving the VVT motor 156 toward the most retarded timing VT1. Here, changing the opening / closing timing VT of the intake valve 128 toward the most retarded angle timing VT1 when the operation of the engine 22 is stopped reduces the energy required for the compression stroke when the engine 22 is next started. This is to improve the startability.

  Subsequently, the coolant temperature Tw of the engine 22 is input (step S120), and it is determined whether or not the input coolant temperature Tw of the engine 22 is less than the threshold value Tref (step S130). Here, the cooling water temperature Tw of the engine 22 is detected by the water temperature sensor 142 and input from the engine ECU 24 by communication. Further, the threshold value Tref sets the opening / closing timing VT of the intake valve 128 to the maximum whether or not the viscosity of the lubricating oil of the engine 22 is sufficiently low, that is, until the crankshaft 26 stops rotating after the fuel cut of the engine 22 is performed. This is for determining whether or not the viscosity of the lubricating oil of the engine 22 is sufficiently low to ensure the time for which the retarding timing VT1 can be set, and is set to, for example, -5 as a value determined in advance through experiments or the like. Temperatures such as ° C. and −10 ° C. can be used.

  When it is determined that the coolant temperature Tw of the engine 22 is equal to or higher than the threshold value Tref, a process of determining whether or not the engine speed Ne of the engine 22 is input and the engine speed Ne of the engine 22 is equal to or less than the stop engine speed Nstop. Is repeatedly executed (steps S170 and S180), and when the rotational speed Ne of the engine 22 reaches the rotational speed Nstop for stopping, the engine ECU 24 is instructed to stop driving the VVT motor 156 (step S190), and this routine is terminated. To do. Here, the stop rotational speed Nstop is used to determine whether or not the rotational speed of the crankshaft 26 has decreased to a speed slightly higher than the speed at which the intake camshaft 152 cannot be driven by the VVT motor 156. For example, a rotational speed such as 80 rpm or 100 rpm can be used as a value determined in advance by experiments or the like.

  When it is determined that the coolant temperature Tw of the engine 22 is lower than the threshold value Tref, the engine timing is changed to the most retarded angle timing VT1 after the fuel cut of the engine 22 is performed until the rotation speed Ne of the engine 22 reaches the stop rotation speed Nstop. Is transmitted to the motor ECU 40, and a torque command for the motor MG1 calculated so that the engine 22 is motored at a predetermined rotation speed Nidl (for example, 800 rpm or 1000 rpm) is determined. (Step S140) After waiting for a predetermined time to elapse (Step S150), a torque command with a value 0 of the motor MG1 is transmitted to the motor ECU 40 so that the motoring of the engine 22 is terminated (Step S160). The motor ECU 40 that has received the torque command of the motor MG1 performs switching control of the switching element of the inverter 41 so that the torque corresponding to the torque command is output from the motor MG1 until the torque command of value 0 is received. Here, the process of motoring the engine 22 is not performed when the operation position of the shift lever 81 is in the parking position, but from the motor MG1 when the operation position of the shift lever 81 is in the traveling or neutral position. The motor MG2 is also controlled such that a torque that cancels the torque output to the ring gear shaft 32a as the drive shaft is output from the motor MG2. In addition, in the embodiment, the predetermined time is a short time that does not cause the driver to feel uncomfortable even if the rotation of the crankshaft 26 of the engine 22 is continued despite being IGOFF by the driver (for example, 0 .3 seconds or 0.5 seconds). Thus, when it is determined that the coolant temperature Tw of the engine 22 is lower than the threshold value Tref, the viscosity of the lubricating oil of the engine 22 is high and the intake valve 128 may not be changed to the most retarded timing VT1. Even so, since the rotation of the intake camshaft 152 is continued with the rotation of the crankshaft 26 due to the motoring of the engine 22, the VVT motor 156 that can be driven only while the intake camshaft 152 is rotating. And the opening / closing timing VT of the intake valve 128 can be changed toward the most retarded angle timing VT1 by driving the VVT motor 156.

  When the motoring of the engine 22 is finished, as described above, after waiting for the rotation speed Ne of the engine 22 to reach the stop rotation speed Nstop (steps S170 and S180), the engine ECU 24 is caused to stop driving the VVT motor 156. An instruction is given (step S190), and this routine is terminated. Here, the stop rotational speed Nstop for stopping the driving of the VVT motor 156 is set in advance as a rotational speed smaller than a predetermined rotational speed Nidl when the engine 22 is motored. The rotation speed smaller than the rotation speed for automatic stop (for example, 200 rpm, 250 rpm, etc.) of the engine 22 that stops the drive of the VVT motor 156 when is established. When the automatic stop condition is satisfied during the intermittent operation of the engine 22, in the embodiment, the engine 22 is temporarily idling, and the opening / closing timing VT of the intake valve 128 is changed toward the most retarded timing VT1 during the idling operation. The VVT motor 156 is driven, then fuel cut is performed, and the driving of the VVT motor 156 is stopped when the rotational speed Ne of the engine 22 reaches the rotational speed for automatic stop described above. The reason for this control is that, unlike when the driver is IGOFF, the engine 22 does not feel uncomfortable even if the fuel cut of the engine 22 is not performed immediately, so the time for idling the engine 22 is secured. This is because the drive of the VVT motor 156 can be stopped after that, and by such control, the opening / closing timing VT of the intake valve 128 is changed to a timing sufficiently close to the most retarded angle timing VT1 during operation of the engine 22. Will be able to. Thus, when the automatic stop condition is satisfied during intermittent operation of the engine 22, even if the opening / closing timing VT of the intake valve 128 becomes the most retarded timing VT1 by driving the VVT motor 156 before and after the fuel cut, the driver Since the drive of the VVT motor 156 is stopped earlier than when the IGOFF is set, it is possible to prevent the VVT motor 156 from being driven more than necessary, such as generating heat with power consumption.

  According to the hybrid vehicle 20 of the embodiment described above, when the operation stop condition that the IGOFF is performed and the cooling water temperature Tw of the engine 22 is less than the threshold value Tref is satisfied, the engine 22 is in a state where the fuel cut of the engine 22 is performed. Is controlled at a predetermined rotational speed Nidl for a predetermined time, so that the VVT motor 156 that can be driven only when the intake camshaft 152 is rotating with the rotation of the crankshaft 26 is controlled. And the opening / closing timing VT of the intake valve 128 can be changed toward the most retarded angle timing VT1 by driving the VVT motor 156. As a result, the energy required for the compression stroke when the engine 22 is next started is reduced, so that the startability when the engine 22 is next started can be improved. Further, since the drive of the VVT motor 156 is continued until the rotational speed Ne of the engine 22 reaches the stop rotational speed Nstop after motoring the engine 22, the opening / closing timing VT of the intake valve 128 is changed toward a later timing. can do. Further, even when the opening / closing timing VT of the intake valve 128 reaches the most retarded angle timing VT1 after motoring the engine 22, when the rotational speed Ne of the engine 22 reaches the stopping rotational speed Nstop, the VVT motor 156 Therefore, the VVT motor 156 can be prevented from being driven more than necessary. On the other hand, when the automatic stop condition is satisfied during intermittent operation of the engine 22, the drive of the VVT motor 156 is stopped when the rotational speed Ne of the engine 22 reaches a rotational speed for automatic stop greater than the rotational speed for stop Nstop. Therefore, the drive of the VVT motor 156 can be stopped more quickly than when the driver makes IGOFF. As a result, it is possible to prevent the VVT motor 156 from being driven more than necessary.

  In the hybrid vehicle 20 of the embodiment, the engine 22 is motored to drive the VVT motor 156 when the operation stop condition that the IGOFF is performed and the coolant temperature Tw of the engine 22 is less than the threshold value Tref is satisfied. Instead of or in addition to the establishment of the operation stop condition due to the coolant temperature Tw of the engine 22, the condition that the temperature of the lubricating oil of the engine 22 is lower than the predetermined temperature and the opening / closing timing VT of the intake valve 128 are from the most retarded angle timing VT1. IGOFF is performed under conditions including at least one of a condition that exceeds a predetermined range, a condition that the rotational speed Ne of the engine 22 is smaller than a predetermined rotational speed Nidl, and that is larger than a rotational speed for determining an operation stop condition. When the operation stop condition is satisfied, the motor 22 is motored and the VVT mode is It may be as to drive the 156, just when the operation stop condition to be IGOFF is established, may alternatively driving the VVT motor 156 of the engine 22 and the motor ring.

  In the hybrid vehicle 20 of the embodiment, when the driver is IGOFF, the rotation speed Ne for the automatic stop in which the rotation speed Ne of the engine 22 stops driving the VVT motor 156 as the automatic stop condition is satisfied during intermittent operation. The drive of the VVT motor 156 is stopped when a smaller stop rotational speed Nstop is reached, but the stop speed is the same as the rotational speed for automatic stop or a stop larger than the rotational speed for automatic stop. The driving of the VVT motor 156 may be stopped when the number of rotations for use is reached.

  In the hybrid vehicle 20 of the embodiment, after motoring the engine 22 for a predetermined time, the drive of the VVT motor 156 is continued until the rotational speed Ne of the engine 22 reaches the rotational speed Nstop for stop. The driving of the VVT motor 156 may be continued until the crankshaft 26 of the engine 22 stops rotating. In the device that can detect that the intake valve 128 has reached the most retarded timing VT1, the most retarded timing VT1 is reached. The driving of the VVT motor 156 may be continued until it is detected that it has been reached, or the driving of the VVT motor 156 may be stopped immediately regardless of the rotational speed Ne of the engine 22.

  In the hybrid vehicle 20 of the embodiment, the variable valve timing mechanism 150 includes a VVT motor 156 as a DC brushless motor that can be driven only while the intake camshaft 152 is rotating as the crankshaft 26 rotates. However, as long as the drive source can be driven only while the intake camshaft 152 is rotating with the rotation of the crankshaft 26, any type of motor may be provided, which is different from the motor. A drive source may be provided.

  In the hybrid vehicle 20 of the embodiment, the power of the motor MG2 is shifted by the reduction gear 35 and output to the ring gear shaft 32a. However, as illustrated in the hybrid vehicle 120 of the modified example of FIG. May be connected to an axle (an axle connected to the wheels 64a and 64b in FIG. 6) different from an axle to which the ring gear shaft 32a is connected (an axle to which the drive wheels 63a and 63b are connected).

  In the hybrid vehicle 20 of the embodiment, the power of the engine 22 is output to the ring gear shaft 32a as the drive shaft connected to the drive wheels 63a and 63b via the power distribution and integration mechanism 30, but the modified example of FIG. The hybrid vehicle 220 includes an inner rotor 232 connected to the crankshaft 26 of the engine 22 and an outer rotor 234 connected to a drive shaft that outputs power to the drive wheels 63a and 63b. A counter-rotor motor 230 that transmits a part of the power to the drive shaft and converts the remaining power into electric power may be provided.

  In the embodiment, an engine 22 and a motor MG1 that output power to a ring gear shaft 32a as a drive shaft via a power distribution and integration mechanism 30, and a motor MG2 that can input and output power to the ring gear shaft 32a via a reduction gear 35, However, as illustrated in the automobile 320 of FIG. 8, the engine 22 that outputs power to the drive shaft connected to the drive wheels 63a and 63b via the transmission 324, The engine 22 may be applied to a motor provided with a motor 326 capable of motoring.

Here, the correspondence between the main elements of the embodiment and the main elements of the invention described in the column of means for solving the problems will be described. In the embodiment, the engine 22 corresponds to an “internal combustion engine”, and an intake camshaft 152 that opens and closes the intake valve 128, a VVT motor 156 that can be driven only while the intake camshaft 152 is rotating, and a movable portion 154, The variable valve timing mechanism 150 having the function of "intake valve opening / closing means" corresponds to the "motor intake means", and the motor MG1 for motoring the engine 22 corresponds to "motoring means". The engine 22 is turned off and the coolant temperature Tw of the engine 22 is lower than the threshold value Tref. When the operation stop condition is established, the engine 22 is instructed to perform fuel cut, and the torque command of the motor MG1 is set and transmitted so that the engine 22 is motored at a predetermined rotational speed Nidl for a predetermined time. In addition, the opening / closing timing VT of the intake valve 128 is set to the most retarded timing VT. The hybrid electronic control unit 70 that executes the processing of steps S100 to S160 for instructing the drive of the VVT motor 156 so as to change toward the motor, the motor ECU 40 that drives the motor MG1 with the received torque command, and the fuel injection are stopped. The engine ECU 24 that drives the VVT motor 156 toward the retard timing VT1 corresponds to a stop time control means. The correspondence between the main elements of the embodiment and the main elements of the invention described in the column of means for solving the problem is the same as that of the embodiment described in the column of means for solving the problem. It is an example for specifically explaining the best mode for doing so, and does not limit the elements of the invention described in the column of means for solving the problem. That is, the interpretation of the invention described in the column of means for solving the problems should be made based on the description of the column, and the examples are those of the invention described in the column of means for solving the problems. It is only a specific example.

  Further, the internal combustion engine device is not limited to the internal combustion engine apparatus mounted on such a hybrid vehicle, but is an internal combustion engine incorporated in a non-moving facility such as an internal combustion engine mounted on a moving body including a vehicle other than an automobile such as a train or a construction facility. An internal combustion engine device such as an engine may be used, or a control method of the internal combustion engine device may be used.

  The best mode for carrying out the present invention has been described with reference to the embodiments. However, the present invention is not limited to these embodiments, and various modifications can be made without departing from the gist of the present invention. Of course, it can be implemented in the form.

  The present invention is applicable to an internal combustion engine device, a vehicle manufacturing industry, and the like.

1 is a configuration diagram showing an outline of the configuration of a hybrid vehicle 20 equipped with an internal combustion engine device according to an embodiment of the present invention. 2 is a configuration diagram showing an outline of the configuration of an engine 22. FIG. 2 is a configuration diagram showing an outline of a configuration of a variable valve timing mechanism 150. FIG. FIG. 5 is an explanatory diagram showing an example of the opening / closing timing of the intake valve 128 when the angle of the intake camshaft 152 is advanced and the opening / closing timing of the intake valve 128 when the angle of the intake camshaft 152 is retarded. It is a flowchart which shows an example of the stop control routine at the time of IGOFF performed by the electronic control unit for hybrids 70 of an Example. FIG. 11 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 120 according to a modification. FIG. 11 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 220 of a modified example. It is a block diagram which shows the outline of a structure of the motor vehicle 320 of a modification.

Explanation of symbols

  20, 120, 220 Hybrid vehicle, 22 engine, 24 engine electronic control unit (engine ECU), 24a CPU, 24b ROM, 24c RAM, 26 crankshaft, 28 damper, 30 power distribution integration mechanism, 31 sun gear, 32 ring gear, 32a ring gear shaft, 33 pinion gear, 34 carrier, 35 reduction gear, 40 motor electronic control unit (motor ECU), 41, 42 inverter, 43, 44 rotational position detection sensor, 50 battery, 51 temperature sensor, 52 battery electronic control Unit (battery ECU), 54 power line, 60 gear mechanism, 62 differential gear, 63a, 63b drive wheel, 64a, 64b wheel, 70 hybrid electronic control unit, 72 CPU, 74 R OM, 76 RAM, 80 ignition switch, 81 shift lever, 82 shift position sensor, 83 accelerator pedal, 84 accelerator pedal position sensor, 85 brake pedal, 86 brake pedal position sensor, 88 vehicle speed sensor, 122 air cleaner, 124 throttle valve, 126 Fuel injection valve, 128 intake valve, 130 spark plug, 132 piston, 134 purification device, 136, throttle motor, 138 ignition coil, 140 crank position sensor, 142 water temperature sensor, 143 pressure sensor, 144 cam position sensor, 146 throttle valve position Sensor, 148 air flow meter, 149 temperature sensor, 150 variable valve timing mechanism, 152 intake Shaft, 154 movable part, 156 VVT motor, 224 motor, 230 pair rotor motor, 232 inner rotor, 234 outer rotor, 320 automobile, 324 transmission, 326 motor, MG1, MG2 motor.

Claims (6)

An internal combustion engine device having an internal combustion engine,
A cam mechanism that is mechanically connected to the output shaft of the internal combustion engine and rotates with the rotation of the output shaft to open and close the intake valve of the internal combustion engine, and can be driven only when the cam mechanism is driven. An intake valve that opens and closes the intake valve so as to change an opening / closing timing with respect to rotation of the output shaft. Opening and closing means;
Motoring means for motoring the internal combustion engine;
When the predetermined operation stop condition is satisfied, the internal combustion engine and the motoring means are controlled so that the internal combustion engine is motored for a predetermined time at a predetermined rotation speed with fuel injection stopped. In order to improve the startability of the next internal combustion engine while the cam mechanism is being driven, the intake valve opening / closing is changed so that the opening / closing timing of the intake valve is changed to the slowest timing within the changeable range. Stop-time control means for controlling the means;
Equipped with a,
The stop time control means is means for stopping the control of the intake valve opening / closing means when the rotational speed of the internal combustion engine reaches a stop rotational speed smaller than the predetermined rotational speed,
The rotation speed for stopping is a rotation for stopping the control of the intake valve opening / closing means when the operation of the internal combustion engine is stopped due to an operation stop condition when the internal combustion engine is intermittently operated different from the predetermined operation stop condition. The number of revolutions is less than the number,
Internal combustion engine device.   2. The internal combustion engine device according to claim 1, wherein the predetermined operation stop condition is a condition including a condition for stopping the operation of the internal combustion engine when the system is turned off.   The internal combustion engine apparatus according to claim 2, wherein the predetermined operation stop condition is a condition including a condition that an engine temperature reflecting physical quantity that is a physical quantity reflecting the temperature of the internal combustion engine is less than a predetermined quantity. The internal combustion engine device according to any one of claims 1 to 3 , wherein the mechanism drive unit is a drive unit including an electric motor as a drive source. A vehicle on which the internal combustion engine device according to any one of claims 1 to 4 is mounted and travels using power from the internal combustion engine. A cam mechanism that is mechanically coupled to an output shaft of the internal combustion engine and rotates with the rotation of the output shaft to open and close the intake valve of the internal combustion engine; and the cam mechanism is driven A mechanism drive unit that drives the cam mechanism to change the phase angle of the cam mechanism with respect to the output shaft, and opens and closes the intake valve so that the opening / closing timing with respect to the rotation of the output shaft can be changed. A control method for an internal combustion engine device comprising: an intake valve opening / closing means for performing; and a motoring means for motoring the internal combustion engine,
When the predetermined operation stop condition is satisfied, the internal combustion engine and the motoring means are controlled so that the internal combustion engine is motored for a predetermined time at a predetermined rotation speed with fuel injection stopped. In order to improve the startability of the next internal combustion engine while the cam mechanism is being driven, the intake valve opening / closing is changed so that the opening / closing timing of the intake valve is changed to the slowest timing within the changeable range. Controlling the means ;
Stopping the control of the intake valve opening and closing means when the rotational speed of the internal combustion engine reaches a stop rotational speed smaller than the predetermined rotational speed,
The rotation speed for stopping is a rotation for stopping the control of the intake valve opening / closing means when the operation of the internal combustion engine is stopped due to an operation stop condition when the internal combustion engine is intermittently operated different from the predetermined operation stop condition. The number of revolutions is less than the number,
A method for controlling an internal combustion engine device.

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