JP2008267200A - Control device for vehicle, its control method, program implementing the method, and recording medium recording the program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve stability of operation operated by pressure changed according to a phase of an intake valve or an exhaust valve. <P>SOLUTION: An ECU executes a program comprising: a step (S110) of controlling a VVT mechanism for intake so that the phase becomes the most retard angle mechanically determining the phase, when an HC adsorption system operated by negative pressure of an intake passage is not in operation (NO in S102); a step (S112) of learning the phase detected by the cam position sensor as the most retarded angle; and a step (S104) of controlling the VVT mechanism for intake so that the phase of the intake valve is advanced up to the phase P(HC) different from the most retarded phase, if the HC adsorption system is in operation. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a vehicle control device, a control method, a program for realizing the method, and a recording medium on which the program is recorded, and more particularly to a technique for learning a phase detected by a detector that detects a phase of a valve.

  Conventionally, VVT (Variable Valve Timing) is known in which the phase (crank angle) at which an intake valve or an exhaust valve opens and closes is changed according to the operating state. In general, in VVT, the phase is changed by rotating a camshaft for opening and closing an intake valve and an exhaust valve relative to a sprocket or the like. The camshaft is rotated by an actuator such as a hydraulic pressure or an electric motor.

  By the way, the range in which the phase can change may change due to the influence of the elongation of the chain connecting the crankshaft and the camshaft. Accordingly, the phase of the most retarded angle and the phase of the most advanced angle that are mechanically determined change with the aging of the internal combustion engine. In this case, for example, the output value from the cam position sensor stored as the output value corresponding to the most retarded phase may differ from the output value corresponding to the actual most retarded phase. Therefore, it is necessary to periodically learn the phase detected by the cam position sensor at the mechanically determined most retarded phase.

  Japanese Patent Laying-Open No. 2001-82190 (Patent Document 1) discloses a valve timing control device that performs learning for a reference position at an early stage when a learning value for deviation from the reference position of a variable valve timing mechanism is cleared. The valve timing control device described in Patent Document 1 learns a deviation between the reference position of the variable valve timing mechanism and the actual valve timing calculated from the crank angle and the cam position, calibrates the actual valve timing, and calibrates the actual valve timing. Is a valve timing control device for the engine that controls the variable valve timing mechanism so as to converge to the target valve timing set based on the engine operating state. The valve timing control device forcibly sets the target valve timing for a set time after engine startup when the learning value for learning the deviation between the reference position of the variable valve timing mechanism and the actual valve timing is cleared. A learning forcing unit that performs learning as a reference position of the timing mechanism is included.

According to the valve timing control device described in this publication, when the learning value for learning the deviation between the reference position of the variable valve timing mechanism and the actual valve timing calculated from the crank angle and the cam position is cleared, the engine is started. During a later set time, learning is performed with the target valve timing forced to be the reference position of the variable valve timing mechanism. As a result, the deviation of the actual valve timing from the reference position can be learned early and reflected in the valve timing control. Therefore, it is possible to ensure the control accuracy and sufficiently bring out the engine output performance.
JP 2001-82190 A

  Incidentally, there are cases where a vehicle is provided with a device that operates using a pressure that changes in accordance with the phase of an intake valve or an exhaust valve, such as a negative pressure in an intake passage of an internal combustion engine. When such a device is operated, if the phase of the intake valve or the exhaust valve is learned, the pressure required for the operation of the device may not be obtained. However, Japanese Patent Laid-Open No. 2001-82190 has no description regarding such a problem.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a vehicle control device, a control method, a program for realizing the method, and a program capable of improving the stability of operation of the device. It is to provide a recording medium on which the program is recorded.

  According to a first aspect of the present invention, there is provided a vehicle control device including an internal combustion engine capable of changing a phase of at least one of an intake valve and an exhaust valve, a detector for detecting the phase of the valve, and a phase of the valve. This is a vehicle control device provided with a device that can be operated by a pressure that changes accordingly. This control device is operated by a learning means for learning a phase detected by the detector in a state in which the phase of the valve is controlled to be the first phase, and a pressure at which the device changes according to the phase of the valve. Means for controlling and if the device is controlled to operate with a pressure that varies with the phase of the valve, the detector is controlled so that the phase of the valve is the first phase. Control means for controlling the phase of the valve to be a second phase different from the first phase in preference to learning the detected phase. The vehicle control method according to the sixth aspect of the invention has the same requirements as the vehicle control apparatus according to the first aspect of the invention.

  According to the first or sixth invention, the vehicle includes an internal combustion engine in which the phase of at least one of the intake valve and the exhaust valve is changed, a detector that detects the phase of the valve, And a device that operates with a pressure that varies with phase. The phase detected by the detector is learned in a state in which the phase of the valve is controlled to be the first phase. Rather than learning the phase detected by the detector with the valve phase controlled to be the first phase when the device is controlled to operate with a pressure that varies with the phase of the valve Preferentially, the valve phase is controlled to be a second phase different from the first phase. As a result, in a state where the device is operated by a pressure that changes in accordance with the phase of the valve, the phase of the valve can be prevented from becoming the first phase and can be set to the second phase. Therefore, fluctuations in pressure used for operating the device can be reduced. As a result, it is possible to provide a vehicle control device or control method that can improve the stability of the operation of the device.

  In the vehicle control apparatus according to the second aspect of the invention, in addition to the configuration of the first aspect of the invention, the learning means causes the valve phase to become the first phase when the fuel injection in the internal combustion engine is stopped. Means for learning the phase detected by the detector in a controlled manner. The control means controls the phase of the valve to be the first phase when fuel injection in the internal combustion engine is stopped and the device is controlled to operate with a pressure that changes according to the phase of the valve. And means for controlling the phase of the valve to be the second phase in preference to learning the phase detected by the detector in this state. The vehicle control method according to the seventh aspect has the same requirements as those of the vehicle control apparatus according to the second aspect.

  According to the second or seventh invention, the fuel injection in the internal combustion engine stops, so that the valve phase is set to the second phase even when the condition for learning the valve phase is satisfied. be able to. Therefore, fluctuations in pressure used for operating the device can be reduced. As a result, the operation stability of the device can be improved.

  In the vehicle control apparatus according to the third aspect of the invention, in addition to the configuration of the first or second aspect of the invention, the device is operated by the pressure in the intake passage of the internal combustion engine. The vehicle control method according to the eighth invention has the same requirements as those of the vehicle control device according to the third invention.

  According to the third or eighth aspect of the invention, it is possible to improve the stability of the operation of the device that is operated by the pressure in the intake passage of the internal combustion engine.

  In the vehicle control apparatus according to the fourth aspect of the invention, in addition to the configuration of the third aspect of the invention, the vehicle is provided with an adsorption member that adsorbs unburned fuel contained in the exhaust gas of the internal combustion engine. The device is operated by the pressure in the intake passage of the internal combustion engine so as to guide the exhaust gas of the internal combustion engine to the adsorption member. The vehicle control method according to the ninth aspect has the same requirements as the vehicle control apparatus according to the fourth aspect.

  According to the fourth or ninth invention, the device operates to guide the exhaust to the adsorbing member that adsorbs the unburned fuel contained in the exhaust of the internal combustion engine. The stability of the operation of this device can be improved. Therefore, the unburned fuel discharged without being adsorbed by the adsorbing member can be reduced.

  In the vehicle control apparatus according to the fifth aspect of the invention, in addition to the configuration of any one of the first to fourth aspects, the first phase is the most retarded phase in a range in which the valve phase can be changed. The vehicle control method according to the tenth invention has the same requirements as the vehicle control device according to the fifth invention.

  According to the fifth or tenth invention, the phase detected as the most retarded phase in the range in which the valve phase can be changed can be learned.

  A program according to an eleventh invention is a program for causing a computer to implement the control method according to any of the sixth to tenth inventions, and the recording medium according to the twelfth invention is any one of the sixth to tenth inventions It is a computer-readable recording medium which recorded the program which makes a computer implement | achieve the control method which concerns on invention.

  According to the eleventh or twelfth invention, the vehicle control method according to any of the sixth to tenth inventions can be realized using a computer (which may be general purpose or dedicated).

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same parts are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed description thereof will not be repeated.

  With reference to FIG. 1, a power train of a hybrid vehicle equipped with a control device according to an embodiment of the present invention will be described. The control device according to the present embodiment is realized, for example, when ECU 100 executes a program recorded in ROM (Read Only Memory) 102 of ECU (Electronic Control Unit) 100. ECU 100 may be divided into a plurality of ECUs. Further, a program executed by the ECU 1000 may be recorded on a recording medium such as a CD (Compact Disc) or a DVD (Digital Versatile Disc) and distributed to the market.

  As shown in FIG. 1, the power train includes an engine 1000, an MG (Motor Generator) (1) 200, and a power split mechanism 300 that synthesizes or distributes torque between the engine 1000 and the MG (1) 200. , MG (2) 400 and transmission 500 are mainly configured.

  The engine 1000 is a known power device that burns fuel and outputs motive power, and is configured to be able to electrically control operating conditions such as throttle opening (intake amount), fuel supply amount, and ignition timing. Yes. The control is performed, for example, by the ECU 100 mainly including a microcomputer. Details of the engine 1000 will be described later.

  The MG (1) 200 is a three-phase AC rotating electric machine as an example, and is configured to generate a function as an electric motor (motor) and a function as a generator (generator). It is connected to a power storage device 700 such as a battery via an inverter 210. By controlling the inverter 210, the output torque or regenerative torque of the MG (1) 200 is set appropriately. The control is performed by the ECU 100. The stator (not shown) of MG (1) 200 is fixed and is not rotated.

  The power split mechanism 300 includes a sun gear (S) 310 that is an external gear, a ring gear (R) 320 that is an internal gear arranged concentrically with the sun gear (S) 310, and the sun gear (S). This is a known gear mechanism that generates a differential action by using a carrier (C) 330 that rotates and revolves a pinion gear meshing with 310 and a ring gear (R) 320 as three rotating elements. The output shaft of the engine 1000 is connected to a carrier (C) 330 as a first rotating element via a damper. In other words, the carrier (C) 330 is an input element.

  On the other hand, the rotor (not shown) of MG (1) 200 is connected to sun gear (S) 310 which is the second rotating element. Therefore, the sun gear (S) 310 is a so-called reaction force element, and the ring gear (R) 320 that is the third rotation element is an output element. The ring gear (R) 320 is connected to an output shaft 600 connected to drive wheels (not shown).

  FIG. 2 shows an alignment chart of the power split mechanism 300. As shown in FIG. 2, when the reaction torque generated by MG (1) 200 is input to sun gear (S) 310 with respect to the torque output from engine 1000 input to carrier (C) 330, these torques are added or subtracted. The torque having the magnitude appears in the ring gear (R) 320 serving as an output element. In that case, the rotor of MG (1) 200 rotates by the torque, and MG (1) 200 functions as a generator. When the rotation speed (output rotation speed) of the ring gear (R) 320 is constant, the rotation speed of the engine 1000 is continuously (steplessly) varied by changing the rotation speed of the MG (1) 200. ) Can be changed. That is, the control for setting the engine speed of the engine 1000 to, for example, the engine speed with the best fuel efficiency can be performed by controlling the MG (1) 200. The control is performed by the ECU 100.

  If engine 1000 is stopped during traveling, MG (1) 200 is rotating in the reverse direction, and when MG (1) 200 is made to function as an electric motor and torque is output in the forward rotation direction, carrier ( C) Torque in a direction for rotating the engine 1000 connected to 330 acts on the engine 1000, and the engine 1000 can be started (motored or cranked) by the MG (1) 200. In that case, torque in a direction to stop the rotation acts on the output shaft 600. Therefore, the driving torque for traveling can be maintained by controlling the torque output by MG (2) 400, and at the same time, engine 1000 can be started smoothly. This type of hybrid type is called a mechanical distribution type or a split type.

  Returning to FIG. 1, MG (2) 400 is a three-phase AC rotating electric machine as an example, and is configured to generate a function as a motor and a function as a generator. A power storage device 700 such as a battery is connected via an inverter 310. By controlling the inverter 310, the power running and regeneration and the torque in each case are controlled. The stator (not shown) of MG (2) 400 is fixed and is not rotated.

  The transmission 500 is configured by a set of Ravigneaux planetary gear mechanisms. A first sun gear (S1) 510 and a second sun gear (S2) 520, which are external gears, are provided, and the first pinion 531 meshes with the first sun gear (S1) 510, and the first The pinion 531 meshes with the second pinion 532, and the second pinion 532 meshes with the ring gear (R) 540 arranged concentrically with the sun gears 510 and 520.

  Each pinion 531 and 532 is held by a carrier (C) 550 so as to rotate and revolve freely. Further, the second sun gear (S 2) 520 is meshed with the second pinion 532. Therefore, the first sun gear (S1) 510 and the ring gear (R) 540 form a mechanism corresponding to the double pinion type planetary gear mechanism together with the pinions 531 and 532, and the second sun gear (S2) 520 and the ring gear (R). 540 and the second pinion 532 constitute a mechanism corresponding to a single pinion planetary gear mechanism.

  Further, the transmission 500 is provided with a B1 brake 561 that selectively fixes the first sun gear (S1) 510 and a B2 brake 562 that selectively fixes the ring gear (R) 540. These brakes 561 and 562 are so-called friction engagement elements that generate an engagement force by a friction force, and a multi-plate type engagement device or a band type engagement device can be adopted. And these brakes 561 and 562 are comprised so that the torque capacity may change continuously according to the engaging force by oil_pressure | hydraulic. Further, the above-described MG (2) 400 is connected to the second sun gear (S2) 520. Carrier (C) 550 is connected to output shaft 600.

  Therefore, in the above-described transmission 500, the second sun gear (S2) 520 is a so-called input element, and the carrier (C) 550 is an output element. By engaging the B1 brake 561, the transmission ratio is “ A high speed stage greater than 1 "is set. By engaging the B2 brake 562 instead of the B1 brake 561, a low speed stage having a higher gear ratio than the high speed stage is set.

  The speed change between the respective speeds is executed based on a traveling state such as a vehicle speed and a required driving force (or accelerator opening). More specifically, the shift speed region is determined in advance as a map (shift diagram), and control is performed so as to set one of the shift speeds according to the detected driving state.

  FIG. 3 shows an alignment chart of the transmission 500. As shown in FIG. 3, if the ring gear (R) 540 is fixed by the B2 brake 562, the low speed stage L is set, and the torque output from the MG (2) 400 is amplified according to the gear ratio, and is output to the output shaft 600. Added. On the other hand, if the first sun gear (S1) 510 is fixed by the B1 brake 561, the high speed stage H having a smaller gear ratio than the low speed stage L is set. Since the gear ratio at the high speed stage H is also larger than “1”, the torque output from the MG (2) 400 is increased according to the gear ratio and added to the output shaft 600.

  In the state where the gears L and H are constantly set, the torque applied to the output shaft 600 is a torque obtained by increasing the output torque of the MG (2) 400 according to the gear ratio. In the shift transition state, the torque is affected by the torque capacity at each brake 561 and 562, the inertia torque accompanying the change in the rotational speed, and the like. Further, the torque applied to the output shaft 600 is a positive torque in the driving state of the MG (2) 400, and is a negative torque in the driven state.

  In the present embodiment, the hybrid vehicle has a first traveling mode that uses only the driving force of engine 1000, a second traveling mode that uses only the driving force of MG (2) 400 while engine 1000 is stopped, engine 1000 and MG. (2) The vehicle travels in any one of the third travel modes using both driving forces of 400. The travel mode is selected based on various parameters such as the accelerator opening and the remaining capacity of power storage device 700.

  In addition, about the selection method of driving modes, what is necessary is just to utilize a well-known technique in the technical field of a hybrid vehicle, Therefore Here, further detailed description is not repeated. Further, the number of modes is not limited to three.

The engine 1000 will be further described with reference to FIG.
The engine 1000 is a V-type 8-cylinder engine in which “A” bank 1010 and “B” bank 1012 are each provided with a group of four cylinders. An engine other than a V-type 8-cylinder engine may be used.

  Engine 1000 receives air from air cleaner 1020. The intake air amount is adjusted by a throttle valve 1030. The throttle valve 1030 is an electronic throttle valve that is driven by a motor.

  Air is introduced into the cylinder 1040 through the intake passage 1032. Air is mixed with fuel in a cylinder 1040 (combustion chamber). Fuel is directly injected from the injector 1050 into the cylinder 1040. That is, the injection hole of the injector 1050 is provided in the cylinder 1040.

  Fuel is injected during the intake stroke. Note that the timing of fuel injection is not limited to the intake stroke. In this embodiment, engine 1000 will be described as a direct injection engine in which an injection hole of injector 1050 is provided in cylinder 1040. In addition to direct injection injector 1050, a port injection injector is provided. May be. Further, only a port injection injector may be provided.

  The air-fuel mixture in the cylinder 1040 is ignited by the spark plug 1060 and burned. The air-fuel mixture after combustion, that is, the exhaust gas is purified by the three-way catalyst 1070 and then discharged outside the vehicle. The piston 1080 is pushed down by the combustion of the air-fuel mixture, and the crankshaft 1090 rotates.

  An intake valve 1100 and an exhaust valve 1110 are provided at the top of the cylinder 1040. Intake valve 1100 is driven by intake camshaft 1120. The exhaust valve 1110 is driven by an exhaust camshaft 1130. Intake camshaft 1120 and exhaust camshaft 1130 are connected by a chain, gear, or the like, and rotate at the same rotational speed.

  Intake camshaft 1120 and exhaust camshaft 1130 are connected to crankshaft 1090 by a chain, a belt, or the like. Intake camshaft 1120 and exhaust camshaft 1130 rotate at half the rotational speed of crankshaft 1090.

  The phase (opening / closing timing) of intake valve 1100 is controlled by intake VVT mechanism 2000 provided on intake camshaft 1120. The phase of the exhaust valve 1110 is controlled by an exhaust VVT mechanism 3000 provided on the exhaust camshaft 1130.

  In the present embodiment, intake camshaft 1120 and exhaust camshaft 1130 are rotated by the VVT mechanism, whereby the phases of intake valve 1100 and exhaust valve 1110 are controlled. That is, the phases of intake valve 1100 and exhaust valve 1110 are changed by changing the phases of intake camshaft 1120 and exhaust camshaft 1130 with respect to crankshaft 1090 by the VVT mechanism. The method for controlling the phase is not limited to this.

  Intake VVT mechanism 2000 is operated by electric motor 2060 (not shown in FIG. 4). Electric motor 2060 is controlled by ECU 100. The current and voltage of the electric motor 2060 are detected by an ammeter (not shown) and a voltmeter (not shown) and input to the ECU 100.

  The exhaust VVT mechanism 3000 is operated by hydraulic pressure. Intake VVT mechanism 2000 may be hydraulically operated, and exhaust VVT mechanism 3000 may be operated by an electric motor.

  ECU 100 receives a signal representing the rotation speed and crank angle of crankshaft 1090 from crank angle sensor 5000. Further, ECU 100 receives from cam position sensor 5010 a signal indicating the phase of intake camshaft 1120 and exhaust camshaft 1130 (the position of the camshaft in the rotational direction) (signal indicating the phase of intake valve 1100 and exhaust valve 1110). Is done. In addition, signals representing the rotational speeds of intake camshaft 1120 and exhaust camshaft 1130 are input from cam position sensor 5010.

  Further, ECU 100 receives a signal representing the water temperature (cooling water temperature) of engine 1000 from water temperature sensor 5020 and a signal representing the intake air amount of engine 1000 (the amount of air sucked into engine 1000) from air flow meter 5030. Is done.

  Further, the ECU 100 receives a signal representing the output shaft rotational speed of the electric motor 2060 from the rotational speed sensor 5040.

  Based on signals input from these sensors, a map and a program stored in a memory (not shown), the ECU 100 controls the throttle opening, ignition timing, fuel injection so that the engine 1000 enters a desired operating state. The timing, fuel injection amount, intake valve 1100 phase, exhaust valve 1110 phase, and the like are controlled.

  In the present embodiment, ECU 100 determines the phase of intake valve 1100 based on a map using engine speed NE and intake air amount KL as parameters, as shown in FIG. A plurality of maps for determining the phase of the intake valve 1100 are stored for each water temperature.

  Hereinafter, the intake VVT mechanism 2000 will be further described. Exhaust VVT mechanism 3000 may have the same configuration as intake VVT mechanism 2000 described below.

  As shown in FIG. 6, intake VVT mechanism 2000 includes sprocket 2010, cam plate 2020, link mechanism 2030, guide plate 2040, speed reducer 2050, and electric motor 2060.

  The sprocket 2010 is connected to the crankshaft 1090 via a chain or the like. The number of revolutions of the sprocket 2010 is one half of the number of revolutions of the crankshaft 1090. An intake camshaft 1120 is provided so as to be concentric with the rotation axis of the sprocket 2010 and to be rotatable relative to the sprocket 2010.

  Cam plate 2020 is connected to intake camshaft 1120 by pin (1) 2070. The cam plate 2020 rotates integrally with the intake camshaft 1120 inside the sprocket 2010. The cam plate 2020 and the intake camshaft 1120 may be formed integrally.

  The link mechanism 2030 includes an arm (1) 2031 and an arm (2) 2032. As shown in FIG. 7, which is a VII-VII cross section in FIG. 6, a pair of arms (1) 2031 are provided in the sprocket 2010 so as to be point-symmetric with respect to the rotation axis of the intake camshaft 1120. Each arm (1) 2031 is connected to the sprocket 2010 so as to be swingable around a pin (2) 2072.

  As shown in FIG. 8 which is a VIII-VIII cross section in FIG. 6 and FIG. 9 in which the phase of the intake valve 1100 is advanced from the state of FIG. 8, the arm (1) 2031 and the cam plate 2020 include: It is connected by an arm (2) 2032.

  The arm (2) 2032 is supported so as to be swingable with respect to the arm (1) 2031 about the pin (3) 2074. The arm (2) 2032 is supported so as to be swingable with respect to the cam plate 2020 around the pin (4) 2076.

  By the pair of link mechanisms 2030, the intake camshaft 1120 rotates relative to the sprocket 2010, and the phase of the intake valve 1100 is changed. Therefore, even if any one of the pair of link mechanisms 2030 is broken due to damage or the like, the phase of the intake valve 1100 can be changed by the other link mechanism.

  Returning to FIG. 6, a control pin 2034 is provided on the surface of each link mechanism 2030 (arm (2) 2032) on the guide plate 2040 side. The control pin 2034 is provided concentrically with the pin (3) 2074. Each control pin 2034 slides in a guide groove 2042 provided in the guide plate 2040.

  Each control pin 2034 is moved in the radial direction by sliding in the guide groove 2042 of the guide plate 2040. By moving each control pin 2034 in the radial direction, the intake camshaft 1120 is rotated relative to the sprocket 2010.

  As shown in FIG. 10 which is an XX section in FIG. 6, the guide groove 2042 is formed in a spiral shape so that each control pin 2034 is moved in the radial direction when the guide plate 2040 rotates. The shape of the guide groove 2042 is not limited to this.

  The more the control pin 2034 is radially away from the axis of the guide plate 2040, the more retarded the phase of the intake valve 1100 is. That is, the amount of change in phase becomes a value corresponding to the amount of operation of the link mechanism 2030 due to the control pin 2034 changing in the radial direction. Note that the phase of the intake valve 1100 may be further advanced as the control pin 2034 moves away from the axis of the guide plate 2040 in the radial direction.

  As shown in FIG. 10, when the control pin 2034 contacts the end of the guide groove 2042, the operation of the link mechanism 2030 is limited. Therefore, the phase at which the control pin 2034 contacts the end of the guide groove 2042 is the most retarded angle or the most advanced phase that is mechanically determined.

  Returning to FIG. 6, the guide plate 2040 is provided with a plurality of recesses 2044 for connecting the guide plate 2040 and the speed reducer 2050 on the surface on the speed reducer 2050 side.

  The reduction gear 2050 includes an external gear 2052 and an internal gear 2054. The external gear 2052 is fixed to the sprocket 2010 so as to rotate integrally with the sprocket 2010.

  The internal gear 2054 is formed with a plurality of convex portions 2056 that are received in the concave portions 2044 of the guide plate 2040. The internal gear 2054 is supported so as to be rotatable about an eccentric shaft 2066 of a coupling 2062 formed eccentrically with respect to the shaft center 2064 of the output shaft of the electric motor 2060.

  The XI-XI cross section in FIG. 6 is shown in FIG. The internal gear 2054 is provided such that some of the plurality of teeth mesh with the external gear 2052. When the output shaft rotational speed of the electric motor 2060 is the same as the rotational speed of the sprocket 2010, the coupling 2062 and the internal gear 2054 rotate at the same rotational speed as the external gear 2052 (sprocket 2010). In this case, the guide plate 2040 rotates at the same rotational speed as the sprocket 2010, and the phase of the intake valve 1100 is maintained.

  When the coupling 2062 is rotated relative to the external gear 2052 around the axis 2064 by the electric motor 2060, the entire internal gear 2054 rotates (revolves) around the axis 2064, The internal gear 2054 rotates around the eccentric shaft 2066. Due to the rotational movement of the internal gear 2054, the guide plate 2040 is rotated relative to the sprocket 2010, and the phase of the intake valve 1100 is changed.

  The phase of intake valve 1100 changes when the relative rotational speed between the output shaft of electric motor 2060 and sprocket 2010 (the amount of operation of electric motor 2060) is decelerated in reduction gear 2050, guide plate 2040, and link mechanism 2030. . The phase of intake valve 1100 may be changed by increasing the relative rotational speed between the output shaft of electric motor 2060 and sprocket 2010.

  As shown in FIG. 12, the overall reduction ratio of intake VVT mechanism 2000 (ratio of the relative rotational speed of output shaft of electric motor 2060 and sprocket 2010 to the amount of change in phase) is a value corresponding to the phase of intake valve 1100. Can take. In the present embodiment, the greater the reduction ratio, the smaller the amount of phase change with respect to the relative rotational speed between the output shaft of electric motor 2060 and sprocket 2010.

  When the phase of intake valve 1100 is in the retarded angle region from the most retarded angle to CA (1), the overall reduction ratio of intake VVT mechanism 2000 is R (1). When the phase of intake valve 1100 is in the advance region from CA (2) (CA (2) is the advance side of CA (1)) to the most advanced angle, the reduction ratio of intake VVT mechanism 2000 as a whole Is R (2) (R (1)> R (2)).

  When the phase of intake valve 1100 is in the intermediate region from CA (1) to CA (2), the reduction ratio of intake VVT mechanism 2000 as a whole is set to a predetermined rate of change ((R (2) −R (1)) / (CA (2) -CA (1))).

  Hereinafter, an operation of the intake VVT mechanism 2000 of the variable valve timing device will be described.

  When the phase of the intake valve 1100 (intake camshaft 1120) is advanced, when the electric motor 2060 is operated and the guide plate 2040 is rotated relative to the sprocket 2010, the intake valve 1100 is shown in FIG. The phase of is advanced.

  When the phase of intake valve 1100 is in the retarded region between the most retarded angle and CA (1), the relative rotational speed between the output shaft of electric motor 2060 and sprocket 2010 is decelerated by reduction ratio R (1). The phase of intake valve 1100 is advanced.

  When the phase of intake valve 1100 is in the advance angle region between CA (2) and the most advanced angle, the relative rotational speed between the output shaft of electric motor 2060 and sprocket 2010 is reduced by reduction ratio R (2). The phase of intake valve 1100 is advanced.

  When retarding the phase, the output shaft of the electric motor 2060 is rotated relative to the sprocket 2010 in the opposite direction to when the phase is advanced. When the phase is retarded, the relative rotational speed between the output shaft of the electric motor 2060 and the sprocket 2010 is the reduction ratio in the retardation region between the most retarded angle and CA (1), as in the case of the advance. The phase is delayed by R (1). In the advance angle region between CA (2) and the most advanced angle, the relative rotational speed between the output shaft of the electric motor 2060 and the sprocket 2010 is reduced by the reduction ratio R (2), and the phase is retarded. .

  As a result, as long as the relative rotation direction of the output shaft of the electric motor 2060 and the sprocket 2010 is the same, the retardation region between the most retarded angle and CA (1) and the most advanced angle CA (2) and The phase of intake valve 1100 can be advanced or retarded in both regions of the advance angle region between. At this time, the phase can be advanced or retarded more greatly in the advance angle region between CA (2) and the most advanced angle. Therefore, the phase can be changed in a large range.

  In addition, in the retardation region between the most retarded angle and CA (1), the reduction ratio is large, so that the output shaft of electric motor 2060 is controlled by the torque acting on intake camshaft 1120 as engine 1000 is operated. A large torque is required for rotation. Therefore, even when the electric motor 2060 is stopped or the like, even when the electric motor 2060 does not generate torque, the rotation of the output shaft of the electric motor 2060 due to the torque acting on the intake camshaft 1120 can be suppressed. it can. Therefore, it is possible to suppress the actual phase from changing from the control phase.

  By the way, when the phase of intake valve 1100 is in an intermediate region between CA (1) and CA (2), the output shaft of electric motor 2060 and sprocket 2010 are set at a reduction ratio that changes at a predetermined rate of change. The relative rotational speed of the intake valve 1100 is decelerated, and the phase of the intake valve 1100 is advanced or retarded.

  As a result, when the phase changes from the retard angle region to the advance angle region, or from the advance angle region to the retard angle region, the phase change amount with respect to the relative rotational speed between the output shaft of the electric motor 2060 and the sprocket 2010 is gradually increased or It can be gradually reduced. Therefore, it is possible to suppress the phase change amount from changing suddenly in steps, and to suppress the phase from changing suddenly. As a result, the phase controllability can be improved.

  Returning to FIG. 6, the electric motor 2060 is duty-controlled by the ECU 100 via an EDU (Electronic Driver Unit) 4000. Here, the duty control is to set a duty ratio indicating a rate at which a switching element (not shown) of the EDU 4000 is turned on, and by operating the switching element at this duty ratio, the operating voltage of the electric motor 2060 is set. It means to control.

  That is, the operating voltage of the electric motor 2060 is a voltage corresponding to the duty ratio. The greater the duty ratio, the higher the operating voltage. The higher the operating voltage, the greater the torque generated by the electric motor 2060. The electric motor 2060 generates a larger torque as the operating current is higher.

  A signal representing the duty ratio set by ECU 100 is output to EDU 4000. The EDU 4000 outputs a voltage corresponding to the duty ratio. Thereby, the electric motor 2060 is driven.

  Instead of setting the duty ratio, the operating voltage or operating current of the electric motor 2060 may be set directly. In this case, the electric motor 2060 may be driven by the set operating voltage or operating current.

  The rotational speed of the electric motor 2060 is a rotational speed corresponding to the torque generated by the electric motor 2060. The rotation speed of electric motor 2060 is detected by rotation speed sensor 5040, and a signal representing the detection result is transmitted to ECU 100.

  For example, the duty ratio is calculated (set) as the sum of the basic duty ratio and the correction duty ratio. The basic duty ratio and the correction duty ratio are determined by, for example, the target phase of intake valve 1100 determined using the map shown in FIG. 5 described above and the rotation speed of intake camshaft 1120 detected using cam position sensor 5010. And the phase (phase of intake valve 1100).

  More specifically, based on the difference ΔCA between the target phase and the detected phase, a required value of the rotational speed difference (relative rotational speed) between the output shaft of the electric motor 2060 and the sprocket 2010 (hereinafter referred to as the required rotational speed difference). Is also calculated). The required rotational speed difference is calculated using, for example, a map created in advance using ΔCA as a parameter. The method for calculating the required rotational speed difference is not limited to this.

  Further, a required value of the rotational speed of the output shaft of electric motor 2060 (hereinafter also referred to as required rotational speed) is calculated as the sum of the required rotational speed difference and the rotational speed of intake camshaft 1120.

  Based on the required rotational speed, the basic duty ratio of the electric motor 2060 is calculated. The basic duty ratio is calculated to a higher value as the required rotational speed is higher. The basic duty ratio is calculated using, for example, a map created in advance with the required rotational speed as a parameter. The method for calculating the basic duty ratio is not limited to this.

  The correction duty ratio is calculated based on the rotational speed difference ΔN between the output shaft rotational speed of the electric motor 2060 and the required rotational speed, which is detected using the rotational speed sensor 5040. The correction duty ratio is calculated as a value obtained by multiplying the rotation speed difference ΔN by the correction coefficient K. The method for calculating the correction duty ratio is not limited to this.

  Returning to FIG. 4, an HC (HydroCarbon) adsorption system 6000 is provided in the hybrid vehicle of the present embodiment. The HC adsorption system 6000 is a system that adsorbs HC, which is an unburned fuel component contained in exhaust gas, on the adsorption member 6010.

  The HC adsorption system 6000 includes a switching valve 6020, a diaphragm 6030, and a vacuum switching valve 6040 in addition to the adsorption member 6010. The adsorbing member 6010 adsorbs HC contained in the exhaust gas. Switching valve 6020 is provided in the exhaust passage of engine 1000. The switching valve 6020 is connected to the diaphragm 6030 via the rod 6022. The switching valve 6020 operates in conjunction with the movement of the diaphragm 6030 so as to switch between a state indicated by a solid line and a state indicated by a broken line in FIG.

  Diaphragm 6030 partitions atmospheric pressure chamber 6032 and negative pressure chamber 6034. The atmospheric pressure in the atmospheric pressure chamber 6032 is the same as the atmospheric pressure. The air pressure in the negative pressure chamber 6034 is switched by the vacuum switching valve 6040 between a state where it is the same as the pressure inside the intake passage 1032 and a state where it is the same as the atmospheric pressure. Vacuum switching valve 6040 is connected to intake passage 1032. Vacuum switching valve 6040 is a solenoid valve controlled by ECU 100.

  For example, the vacuum switching valve 6040 is turned on in order to bring the HC adsorption system 6000 into an operating state in an operating state in which exhaust gas is considered to contain a large amount of HC, for example, before the engine 1000 is warmed up. . When the vacuum switching valve 6040 is turned on, the atmospheric pressure in the negative pressure chamber 6034 becomes the same as the pressure in the intake passage 1032. In this state, the diaphragm 6030 is bent. When the diaphragm 6030 is bent, the switching valve 6020 is in a state indicated by a solid line in FIG. In this state, the exhaust gas is guided to the adsorption member 6010. Therefore, HC contained in the exhaust gas is adsorbed by the adsorbing member 6010.

  For example, the vacuum switching valve 6040 is turned off in order to put the HC adsorption system 6000 in a stopped state in an operating state in which exhaust gas contains less HC, for example, after the engine 1000 has been warmed up. The When the vacuum switching valve 6040 is turned off, the atmospheric pressure in the negative pressure chamber 6034 becomes the same as the atmospheric pressure. In this state, the diaphragm 6030 is not bent. Thereby, the switching valve 6020 is in a state indicated by a broken line in FIG. In this state, the adsorbing member 6010 is blocked from the exhaust gas.

  The function of the ECU 100 will be described with reference to FIG. Note that the functions of the ECU 100 described below may be realized by hardware or software.

  ECU 100 includes a learning unit 110, an adsorption system control unit 120, a first phase control unit 131, and a second phase control unit 132.

  When performing fuel cut to stop fuel injection in engine 1000, learning unit 110 controls intake VVT mechanism 2000 so that the phase is the most retarded phase that is mechanically determined, and the cam position in this state The output value of the sensor 5010, that is, the phase detected by the cam position sensor 5010 is learned.

  That is, the learning unit 110 learns the phase detected by the cam position sensor 5010 as the most retarded phase when performing fuel cut. For example, the initial value stored as the most retarded phase is replaced with the detected phase. Note that the deviation between the initial value and the detected phase may be learned. Further, the method of learning the phase is not limited to these. Furthermore, the phase may be learned when the hybrid vehicle travels in the second travel mode.

  For example, the phase is retarded at a constant duty ratio until the phase change detected by the cam position sensor 5010 becomes “0”, so that the phase becomes the most retarded phase. The method for setting the phase to the most retarded phase is not limited to this.

  The adsorption system control unit 120 controls the state of the switching valve 6020 by controlling the vacuum switching valve 6040. As described above, the vacuum switching valve 6040 is turned on in an operation state in which the exhaust gas is considered to contain a lot of HC, for example, before the warm-up of the engine 1000 is completed. When the vacuum switching valve 6040 is turned on, exhaust gas is guided to the adsorbing member 6010 by the switching valve 6020. On the other hand, for example, after the engine 1000 has been warmed up, the vacuum switching valve 6040 is turned off in an operation state in which the HC contained in the exhaust gas is considered to be low. When the vacuum switching valve 6040 is turned off, the adsorption member 6010 is cut off from the exhaust gas by the switching valve 6020.

  As shown in FIG. 15, the first phase control unit 131 is the most powerful when the engine 1000 is driven (when the engine 1000 outputs torque by fuel injection and ignition). Intake VVT mechanism 2000 (electric motor 2060) is controlled so that the phase changes in the second range of the first range from the retarded phase to the most advanced phase. The second range does not include the most retarded phase.

  In the present embodiment, among the first range, the third range including the most retarded phase is used only when engine 1000 is started. This is because the most retarded phase is determined so that the phase of the intake valve 1100 is largely retarded in order to reduce the vibration at the start-up by reducing the compression ratio. Therefore, for example, when engine 1000 is stopped, intake VVT mechanism 2000 is controlled so that the phase becomes the most retarded phase.

  When the HC adsorption system 6000 is operated, that is, when the vacuum switching valve 6040 is turned on and HC is adsorbed by the adsorption member 6010, the second phase control unit 132 advances the phase of the intake valve 1100 to the phase P (HC). The intake VVT mechanism 2000 is controlled so as to be square. For example, intake VVT mechanism 2000 is controlled until the phase detected by cam position sensor 5010 reaches phase P (HC).

  The phase P (HC) is defined as a phase capable of obtaining a negative pressure necessary for bending the diaphragm 6030. The phase P (HC) is a phase different from the most retarded phase. The phase P (HC) is determined in advance by, for example, experiments or simulations.

  When fuel cut is executed, the second phase control unit 132 takes the intake up to the phase P (HC) in preference to learning the phase detected by the cam position sensor 5010 at the most retarded phase. The phase of the valve 1100 is advanced.

  With reference to FIG. 16, a control structure of a program executed by ECU 100 as the control device according to the present embodiment will be described. Note that the program described below is repeatedly executed at a predetermined cycle.

  In step (hereinafter, step is abbreviated as S) 100, ECU 100 determines whether or not to execute fuel cut. If the fuel cut is to be executed (YES in S100), the process proceeds to S102. If not (NO in S100), the process proceeds to S120.

  In S102, ECU 100 determines whether or not HC adsorption system 6000 is operating, that is, whether or not HC is being adsorbed. If HC adsorption system 6000 is operating (YES in S102), the process proceeds to S104. If not (NO in S102), the process proceeds to S110. In S104, ECU 100 controls intake VVT mechanism 2000 so that the phase of intake valve 1100 advances to phase P (HC).

  In S110, ECU 100 controls intake VVT mechanism 2000 so that the phase is the most retarded phase that is mechanically determined. In S112, ECU 100 learns the phase detected by cam position sensor 5010 as the most retarded phase.

  In S120, ECU 100 determines whether engine 1000 is being driven or not. If engine 1000 is being driven (YES in S120), the process proceeds to S122. Otherwise (NO in S120), this process ends. In S122, ECU 100 controls intake VVT mechanism 2000 so that the phase changes in the second range not including the most retarded phase.

  An operation of ECU 100 serving as the control device according to the present embodiment based on the structure and flowchart as described above will be described.

  When fuel cut is executed (YES in S100), if HC adsorption system 6000 is not in operation (NO in S102), intake VVT mechanism 2000 is set so that the phase is the most retarded phase that is mechanically determined. It is controlled (S110). In this state, the phase detected by the cam position sensor 5010 is learned as the most retarded phase (S112).

  By the way, when the phase of the most retarded angle is learned during the operation of the HC adsorption system 6000, the timing for closing the intake valve 1100 is greatly delayed. In this state, the amount of air returned from the cylinder 1040 to the intake passage 1032 in the compression stroke increases. Therefore, the pressure in the intake passage 1032 becomes high, and it may not be possible to obtain the negative pressure necessary to bend the diaphragm 6030. As a result, the operation of the switching valve 6020, that is, the operation of the HV adsorption system 6000 may become unstable.

  Therefore, even when fuel cut is executed (YES in S100), if HC adsorption system 6000 is operating (YES in S102), the phase of intake valve 1100 is advanced to phase P (HC). Thus, the intake VVT mechanism 2000 is controlled (S104). That is, during operation of the HC adsorption system 6000, the phase of the intake valve 1100 is advanced to the phase P (HC) in preference to learning of the most retarded phase.

  As a result, during operation of the HC adsorption system 6000, the phase of the intake valve 1100 can be prevented from reaching the most retarded phase. Further, the phase of intake valve 1100 can be advanced to phase P (HC) at which a necessary negative pressure can be obtained. Therefore, the fluctuation of the negative pressure in the intake passage 1032 can be reduced. As a result, the operation stability of the HC adsorption system 6000 can be improved.

  By the way, in order to reduce the vibration at the time of starting by reducing the compression ratio, the phase of the most retarded angle is determined so that the phase of the intake valve 1100 is largely retarded. Therefore, when the phase is set to the most retarded phase while the engine 1000 is driven, the phase is retarded more than necessary. In this case, for example, the emission performance may be deteriorated. Further, a shock due to a decrease in the output of engine 1000 may occur.

  Therefore, when engine 1000 is being driven (YES in S120), intake VVT mechanism 2000 is controlled so that the phase changes in the second range not including the most retarded phase (S122).

  As described above, according to the ECU that is the control device according to the present embodiment, during the operation of the HC adsorption system that is operated by the negative pressure in the intake passage, priority is given to learning of the phase of the most retarded angle. The phase of the intake valve is advanced to the phase P (HC). Thereby, during operation of the HC adsorption system, the phase of the intake valve can be prevented from reaching the most retarded phase. Further, the phase of the intake valve can be advanced to the phase P (HC) at which a necessary negative pressure can be obtained. Therefore, the stability of the operation of the HC adsorption system can be improved.

  Instead of learning the phase of the most retarded angle, the phase of the most advanced angle may be learned. Further, the control device according to the present embodiment is not limited to the case of learning the phase of intake valve 1100 but can be applied to the case of learning the phase of exhaust valve 1110.

  Furthermore, the device that operates using the pressure that changes depending on the phase of the intake valve 1100 or the exhaust valve 1110 is not limited to the HC adsorption system. Can be used.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

It is a schematic block diagram which shows the power train of a hybrid vehicle. It is an alignment chart of a power split mechanism. It is an alignment chart of a transmission. It is a schematic block diagram which shows the engine of a hybrid vehicle. It is a figure which shows the map which defined the phase of the intake valve. It is sectional drawing which shows the VVT mechanism for intake. It is VII-VII sectional drawing of FIG. It is VIII-VIII sectional drawing (the 1) of FIG. It is VIII-VIII sectional drawing (the 2) of FIG. It is XX sectional drawing of FIG. It is XI-XI sectional drawing of FIG. It is a figure which shows the reduction ratio as the whole VVT mechanism for intake. It is a figure which shows the relationship between the phase of the guide plate with respect to a sprocket, and the phase of an intake valve. It is a functional block diagram of ECU. It is a figure which shows the range from which a phase changes. It is a flowchart which shows the control structure of the program which ECU performs.

Explanation of symbols

  100 ECU, 102 ROM, 110 Learning unit, 120 Adsorption system control unit, 131 First phase control unit, 132 Second phase control unit, 200 MG (1), 300 Power split mechanism, 310 Sun gear (S), 320 Ring gear ( R), 330 Carrier (C), 400 MG (2), 500 Transmission, 510 First sun gear (S1), 520 Second sun gear (S2), 531 First pinion, 532 Second pinion, 540 Ring gear ( R), 550 carrier (C), 561 B1 brake, 562 B2 brake, 600 output shaft, 700 power storage device, 1000 engine, 1010 “A” bank, 1012 “B” bank, 1020 air cleaner, 1030 throttle valve, 1040 cylinder, 1050 injector, 1060 Fire plug, 1070 three-way catalyst, 1090 crankshaft, 1100 intake valve, 1110 exhaust valve, 1120 intake camshaft, 1130 exhaust camshaft, 2000 intake VVT mechanism, 2010 sprocket, 2020 cam plate, 2030 link mechanism, 2031 arm ( 1), 2032 Arm (2), 2034 Control pin, 2040 Guide plate, 2042 Guide groove, 2044 Recess, 2050 Reducer, 2052 External gear, 2054 Internal gear, 2056 Convex, 2060 Electric motor, 2062 Coupling, 2064 shaft, 2066 eccentric shaft, 2070 pin (1), 2072 pin (2), 2074 pin (3), 2076 pin (4), 3000 exhaust VVT mechanism, 4000 EDU, 5000 crank angle sensor, 5010 cam position sensor, 5020 water temperature sensor, 5030 air flow meter, 5040 rpm sensor, 6000 HC adsorption system, 6010 adsorption member, 6020 switching valve, 6022 rod, 6030 diaphragm, 6032 large Air pressure chamber, 6034 Negative pressure chamber, 6040 Vacuum switching valve.

Claims (12)

An internal combustion engine that can change the phase of at least one of an intake valve and an exhaust valve, a detector that detects the phase of the valve, and a device that can be operated by a pressure that changes according to the phase of the valve And a vehicle control device provided with
Learning means for learning the phase detected by the detector in a state where the phase of the valve is controlled to be the first phase;
Means for controlling the device to operate with a pressure that varies with the phase of the valve;
When the device is controlled to operate with a pressure that changes according to the phase of the valve, the phase detected by the detector in a state in which the phase of the valve is controlled to be the first phase. A control apparatus for a vehicle, comprising: control means for controlling the valve phase to be a second phase different from the first phase in preference to learning. The learning means is means for learning a phase detected by the detector in a state where the phase of the valve is controlled to be the first phase when fuel injection in the internal combustion engine is stopped. Including
When the fuel injection in the internal combustion engine is stopped and the device is controlled to operate with a pressure that changes according to the phase of the valve, the control means controls the phase of the valve to be the first Means for controlling the phase of the valve to be the second phase in preference to learning the phase detected by the detector in a state controlled to be in phase. Item 2. The vehicle control device according to Item 1.   The vehicle control device according to claim 1, wherein the device is operated by pressure in an intake passage of the internal combustion engine. The vehicle is provided with an adsorbing member that adsorbs unburned fuel contained in the exhaust of the internal combustion engine,
The vehicle control device according to claim 3, wherein the device is operated by a pressure in an intake passage of the internal combustion engine so as to guide exhaust gas of the internal combustion engine to the adsorption member.   5. The vehicle control device according to claim 1, wherein the first phase is a most retarded phase in a range in which the phase of the valve can be changed. An internal combustion engine that can change the phase of at least one of an intake valve and an exhaust valve, a detector that detects the phase of the valve, and a device that can be operated by a pressure that changes according to the phase of the valve And a vehicle control method provided with
Learning a phase detected by the detector in a state where the phase of the valve is controlled to be a first phase;
Controlling the device to operate with a pressure that varies with the phase of the valve;
When the device is controlled to operate with a pressure that changes according to the phase of the valve, the phase detected by the detector in a state in which the phase of the valve is controlled to be the first phase. And a step of controlling the valve so that the phase of the valve becomes a second phase different from the first phase in preference to learning. The step of learning the phase detected by the detector is detected by the detector in a state where the phase of the valve is controlled to be the first phase when fuel injection in the internal combustion engine is stopped. Learning the phase to be
The step of controlling the phase of the valve to be the second phase is such that fuel injection in the internal combustion engine is stopped and the device is operated by a pressure that changes according to the phase of the valve. When controlled, the phase of the valve is prioritized over learning the phase detected by the detector in a controlled manner so that the phase of the valve is the first phase. The vehicle control method according to claim 6, comprising a step of controlling the phase to be in phase.   The vehicle control method according to claim 6, wherein the device is operated by pressure in an intake passage of the internal combustion engine. The vehicle is provided with an adsorbing member that adsorbs unburned fuel contained in the exhaust of the internal combustion engine,
The vehicle control method according to claim 8, wherein the device is operated by pressure in an intake passage of the internal combustion engine so as to guide exhaust gas of the internal combustion engine to the adsorption member.   10. The vehicle control method according to claim 6, wherein the first phase is a most retarded phase in a range in which the phase of the valve can be changed.   The program which makes a computer implement | achieve the control method in any one of Claims 6-10.   The computer-readable recording medium which recorded the program which makes a computer implement | achieve the control method in any one of Claims 6-10.

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