JP2010127074A - Vehicle control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vehicle control device improving performance such as fuel economy, by properly switching a whole cylinder operating mode, a partial cylinder stopping mode, and a whole cylinder stopping mode in response to an operation state of a vehicle. <P>SOLUTION: In Step 3, when determining that a target travel load value Lt is larger than a predetermined load value L2, in Step 11, large torque is generated from an internal combustion engine 51 by burning in the whole cylinders of right and left banks. In Step 4, when determining that the target travel load value Lt is larger than an intermediate load value L1, in Step 12, three cylinders on the right bank side are stopped, and are controlled in combustion (cylinder reduction operation) of only the left bank side. Since a combustion load of an operating cylinder is enhanced due to this cylinder reduction operation, a pumping loss is reduced, and the combustion is also improved. Heat efficiency itself is also enhanced. Thus, fuel consumption of the internal combustion engine 51 is largely reduced more than the whole cylinder operating operation. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a vehicle control apparatus that uses an internal combustion engine and an electric motor in combination as power sources for a vehicle and controls both power sources in accordance with the driving state of the vehicle.

  As a conventional vehicle control apparatus, what is described in the following patent document 1 filed earlier by the present applicant is known.

  This conventional technique includes a variable lift mechanism that controls the lift amount and operating angle of an engine valve that is an intake valve or an exhaust valve of an internal combustion engine, and when the required deceleration value is equal to or less than a predetermined value when the vehicle decelerates. And zero lift conversion means for controlling the engine valves of all the cylinders to zero lift (closed) by the variable lift mechanism and simultaneously controlling all the cylinders to be deactivated.

  Further, when the driver performs a brake operation during braking of the vehicle, by performing the all cylinder stop control, a gas exchange loss due to the engine valve is avoided, and the so-called engine brake becomes difficult to operate. Thereby, deceleration of the vehicle by the internal combustion engine is suppressed, and it becomes possible to increase the energy recovery efficiency of regenerative electricity by the electric motor. As a result, the fuel consumption of the vehicle can be improved.

Here, the cylinder stop refers to a state in which the basic cycle (intake, compression, expansion, exhaust) of the internal combustion engine is not performed and intake and exhaust valve characteristics are achieved. Normally, the state in which the intake / exhaust valve is not lifted (operated) corresponds to cylinder stop. Therefore, it does not mean that the engine rotation is stopped, but shows an aspect of the intake and exhaust valves.
JP 2001-140665 A

  However, in the conventional vehicle control device, although the fuel consumption performance can be obtained to some extent by controlling the operation angle of the intake valve and the exhaust valve, the operation mode of the internal combustion engine operates the intake valve and the exhaust valve of all cylinders. The fuel consumption reduction effect is naturally limited because it is limited to either one of all cylinders to be operated or all cylinders to stop the operation of the intake valves and exhaust valves of all cylinders.

  The present invention has been devised in view of the technical problem of the conventional vehicle control device, and the invention according to claim 1 is directed to all cylinders for stopping the operation of intake valves and exhaust valves of all cylinders of an internal combustion engine. A stop mode, a partial cylinder stop mode for stopping the operation of intake valves and exhaust valves of some cylinders of the internal combustion engine, an all-cylinder operation mode for operating intake valves and exhaust valves of all cylinders of the internal combustion engine, Is switched according to the driving state of the vehicle.

  According to the present invention, various vehicle performances such as fuel efficiency can be further improved.

Hereinafter, an embodiment of a vehicle control device according to the present invention will be described in detail with reference to the drawings. In this embodiment, the present invention is applied to a so-called hybrid vehicle using a spark ignition gasoline V-type 6-cylinder internal combustion engine and an electric motor as a power source of the vehicle.
[First Embodiment]
First, the overall system of the vehicle will be described with reference to FIG. 1. The crankshaft 51a of the six-cylinder internal combustion engine 51 and one end of the motor shaft 52a of the electric motor 52 are connected via a first clutch 53 so as to be intermittent. In addition, the other end of the motor shaft 52 a and the output shaft 54 a of the transmission 54 are connected via a second clutch 55 so as to be intermittent. Further, the rotational force of the input shaft 54 b of the transmission 54 is transmitted from the axle 57 to the rear wheels 61 and 61 via the differential gear 56.

  The electric motor 52 is supplied with a drive current from a battery 59 via an inverter 58.

  The operation of the first clutch 53, the second clutch 55, and the inverter 58 is controlled by a control signal from the control unit 22 described later, and the current charged amount (SOC) of the battery 59 is shown in FIG. It is input to the control unit 22 from an external detection sensor.

  Further, a transmission (gear position change) control signal from the control unit 22 is output to the transmission 54.

  The electric motor 52 causes the vehicle to travel by the drive current from the battery 59 in an operation region where the power efficiency of the internal combustion engine 51 is poor, such as when the vehicle starts or when the vehicle is running at a low load. It also has a function as a starter motor for the internal combustion engine 51.

  As shown in FIG. 1, the internal combustion engine 51 is a cylinder group in which the three cylinders of the right bank RB can be stopped (cylinder group in which some cylinders can be stopped), while the second cylinder group 3 The left bank LB of the cylinders is also a cylinder group that can be deactivated.

  Further, as shown in FIG. 2, the internal combustion engine 51 includes two intake valves 4 and 4 and exhaust valves 5 and 5 for each cylinder, and the right bank RB includes a valve lift of the intake valves 4 and 4. A first intake VEL1 that is an intake side variable mechanism that variably controls the amount and operating angle, and a first intake VTC2 that is an intake side phase variable mechanism that variably controls the opening and closing timing of the intake valves 4 and 4 are provided. A first exhaust VVL3 is provided as an exhaust side lift variable mechanism that variably controls the valve lift amount of the exhaust valves 5 and 5. The first intake VEL1, the first intake VTC2 and the first exhaust VVL3 perform variable control including valve stop of the intake valves 4 and 4 and valve stop control of the exhaust valves 5 and 5 according to the engine operating state. It has become.

  On the other hand, the left bank LB includes a second intake VEL1 ′ and a second intake VTC2 ′ that variably control the valve lift amount and the opening / closing timing of the intake valves 4 and 4, respectively, and the exhaust valves 5 and 5 are also connected to the second bank LB. Two exhaust VVL3 'is provided.

  A more specific configuration of the internal combustion engine 51 will be described with reference to FIG. 2. The piston 01 is provided in a cylinder bore formed in the cylinder block SB so as to be slidable up and down, and is formed inside the cylinder head SH. The intake ports 02 and exhaust ports 03, and the intake valves 4 and 4 and the exhaust valves 5 and 5 that are slidably provided on the cylinder head SH and open and close the open ends of the intake and exhaust ports 02 and 03. And.

  The piston 01 is connected to the crankshaft 04 via a connecting rod 05, and forms a combustion chamber 06 between the crown surface and the lower surface of the cylinder head SH.

  Inside the intake pipe 010 upstream of the intake manifold 09 for diverting intake air (air mixture) to each intake port 02, a throttle valve 07 for auxiliary control of the intake air amount is provided mainly for safety. ing. The cylinder head SH is provided with a fuel injection valve 08 that injects fuel directly into the combustion chamber 06.

  The first intake VEL1 of the right bank RB is configured to continuously control the valve lift amount of the intake valves 4 and 4 from zero lift (valve stop) to the maximum lift amount. The configuration is the same as that described in, for example, Japanese Patent Application Laid-Open No. 2004-76618 previously filed by the present applicant, and will be briefly described.

  As shown in FIG. 3, a hollow drive shaft 6 rotatably supported by a bearing at the top of the cylinder head SH, and a drive cam 7 which is an eccentric rotary cam fixed to the drive shaft 6 by press-fitting or the like. The intake valves 4, 4 are slidably contacted with the upper surfaces of the valve lifters 8, 8 supported on the outer peripheral surface of the drive shaft 6 and arranged at the upper ends of the intake valves 4, 4. The two swing cams 9 and 9 to be transmitted, and a transmission mechanism linked between the drive cam 7 and the swing cams 9 and 9 for transmitting the rotational force of the drive cam 7 as the swing force of the swing cams 9 and 9. And.

  The drive shaft 6 receives a rotational force from the crankshaft of the engine, and the rotational direction is set in the clockwise direction (arrow direction) in FIG.

  The drive cam 7 has a substantially ring shape, and is fixed to the drive shaft 6 through a drive shaft insertion hole formed in the inner axial direction. The shaft center of the cam body extends from the shaft center of the drive shaft 6. Offset by a predetermined amount in the radial direction.

  As shown in FIGS. 4 and 5 (both in the rear view), both the swing cams 9 have substantially the same raindrop shape and are integrally provided at both ends of the annular camshaft 10. In addition, the camshaft 10 is rotatably supported on the drive shaft 6 via the inner peripheral surface. A cam surface 9a is formed on the lower surface, a base circle surface on the shaft side of the camshaft 10, a ramp surface extending in an arc shape from the base circle surface to the cam nose portion side, and from the ramp surface to the distal end side of the cam nose portion. A lift surface connected to the top surface of the maximum lift is formed, and the base circle surface, the ramp surface, and the lift surface are in contact with predetermined positions on the upper surface of each valve lifter 8 according to the swing position of the swing cam 9. It comes to touch.

  The transmission mechanism includes a rocker arm 11 disposed above the drive shaft 6, a link arm 12 linking the one end 11 a of the rocker arm 11 and the drive cam 7, the other end 11 b of the rocker arm 11, and a swing cam 9. And a link rod 13 that cooperates with each other.

  The rocker arm 11 has a cylindrical base portion at the center thereof rotatably supported by a control cam 18 (described later) through a support hole, and one end portion 11 a is rotatably connected to the link arm 12 by a pin 14. On the other hand, the other end portion 11 b is rotatably connected to one end portion 13 a of the link rod 13 via a pin 15.

  The link arm 12 has a fitting hole in which the cam body of the drive cam 7 is rotatably fitted at the center position of a relatively large-diameter annular base 12a, while the protruding end 12b is the pin. 14 is connected to one end 11a of the rocker arm.

  The other end portion 13 b of the link rod 13 is rotatably connected to the cam nose portion of the swing cam 9 via a pin 16.

  A control shaft 17 is rotatably supported by the same bearing above the drive shaft 6 and is slidably fitted into the support hole of the rocker arm 11 on the outer periphery of the control shaft 17. A control cam 18 serving as a swing fulcrum is fixed.

  The control shaft 17 is disposed in the longitudinal direction of the engine in parallel with the drive shaft 6 and is rotationally controlled by a drive mechanism 19. On the other hand, the control cam 18 has a cylindrical shape, and the axial center position is deviated from the axial center of the control shaft 17 by a predetermined amount.

  The drive mechanism 19 includes a drive motor 20 fixed to one end of a housing (not shown), and a ball screw transmission means 21 provided inside the housing for transmitting the rotational driving force of the drive motor 20 to the control shaft 17. It is composed of

  The drive motor 20 is constituted by a proportional DC motor, and is driven by a control signal from the control unit 22 which is an ECU that detects the state of the vehicle including the engine operation state.

  The ball screw transmission means 21 includes a ball screw shaft 23 disposed substantially coaxially with the drive shaft of the drive motor 20, a ball nut 24 that is a moving member screwed onto the outer periphery of the ball screw shaft 23, and the control It is mainly comprised from the linkage arm 25 connected with the one end part of the axis | shaft 17 along the diameter direction, and the link member 26 which links this linkage arm 25 and the said ball nut 24. As shown in FIG.

  In the ball screw shaft 23, a ball circulation groove having a predetermined width is continuously formed spirally on the entire outer peripheral surface excluding both ends, and one end is coupled to the drive shaft of the drive motor 20, The rotational driving force of the drive motor 20 is transmitted to the ball screw shaft 23, and the ball screw shaft 23 is allowed to move slightly in the axial direction.

  The ball nut 24 is formed in a substantially cylindrical shape, and a guide groove for continuously holding a plurality of balls is formed in a spiral manner in cooperation with the ball circulation groove on the inner peripheral surface. A moving force in the axial direction is applied through each ball while converting the rotational motion of the ball screw shaft 23 into the linear motion of the ball nut 24.

  Further, as shown in FIG. 3, the ball nut 24 includes a first coil spring 27 elastically mounted on the tip side of the ball screw shaft 23 and a second coil elastically mounted on the rear end side of the ball screw shaft 23. Both opposing spring forces with the spring 28 act.

  Therefore, even if the ball nut 24 stops at any position after a failure or a normal engine stop, the coil springs 27 and 28 hold the ball nut 24 at an intermediate position in the axial direction that is not zero lift, thereby starting the engine. Can be ensured, and since it is not the maximum lift control position, the friction of the valve operating device can be reduced and the cranking torque can be reduced, so that even better startability can be obtained.

  The control unit 22 controls the operation by outputting control signals to the second intake VEL1 ′, VTC2 ′ and the second exhaust VVL3 ′, which will be described later, together with the first intake VEL1, VTC2 and the first exhaust VVL3. Yes.

  That is, in addition to the crank angle signal, the engine speed signal, the accelerator opening signal, the vehicle speed signal, and the gear position signal from each sensor, the rotation angle of the control shaft 17 (left and right banks first and second intake VEL1, 1 ' From the angle detection sensors 29a and 29a ′ for detecting the actual position) and the angle detection sensors 29b and 29b ′ for detecting the rotation angle of the drive shaft 6 (the actual positions of the first and second intake VTCs 2 and 2 ′ of the left and right banks). Based on the input signal, the current engine operating state is detected, and a control current is output to the drive motors 20 and 20 ′. Further, depending on the engine operating state, the switching control valve 43 (described later) of the first exhaust VVL3 and the second exhaust VVL3 ′, the drive motor 20 ′ (described later) of the second intake VEL1 ′, and the electromagnetic coils of the second intake VTC2 ′ (described later). A control current is output.

  Hereinafter, an example of the operation of the first intake VEL1 will be briefly described. First, the zero lift, that is, the valve stop operation will be described. In a vehicle traveling low load region that travels with the electric motor 52, when the rotational torque transmitted to the drive motor 20 by the control signal from the control unit 22 is transmitted to the ball screw shaft 23 and rotated, the ball nut 24 is unidirectional. As a result, the control shaft 17 rotates to the maximum in one direction via the link member 26 and the linkage arm 25.

  Therefore, as shown in FIGS. 4A and 4B, the control cam 18 rotates with the same radius around the axis of the control shaft 17, and the thick portion moves away from the drive shaft 6 upward. As a result, the pivotal support point of the other end portion 11 b of the rocker arm 11 and the link rod 13 moves upward with respect to the drive shaft 6. Therefore, each swing cam 9 is connected to the cam nose portion 21 via the link rod 13. The side is forcibly pulled up and the whole is rotated clockwise.

  Therefore, when the drive cam 7 rotates and pushes up the one end portion 11a of the rocker arm 11 via the link arm 12, the valve lift amount is transmitted to the swing cam 9 and the valve lifter 16 via the link rod 13. The lift amount is as shown in FIG. That is, this causes the intake valves 4 and 4 to be in a valve stop state. Here, the valve stop is a state in which no fuel is injected from the combustion injection valve 08 into the cylinder, and no output torque is generated without ignition of the spark plug. At this time, the exhaust valve is also controlled to zero lift by the first exhaust VVL3, and the cylinder is stopped.

  Next, when the vehicle traveling load shifts to a high load region, the drive motor 20 rotates in reverse by a control signal from the control unit 22, and when this rotational torque is transmitted to the ball screw shaft 23 and rotated, Accordingly, the ball nut 24 linearly moves in the opposite direction. Therefore, the control shaft 17 rotates the control cam 18 counterclockwise to rotate the center of the control cam downward as shown in FIGS. 5A and 5B as an example. For this reason, the entire rocker arm 11 moves in the direction toward the drive shaft 6 and the other end 11b presses the cam nose portion of the swing cam 9 downward via the link rod 13 so that the swing cam 9 The whole is rotated clockwise by a predetermined amount.

  Therefore, when the drive cam 7 rotates and pushes up the one end 11a of the rocker arm 11 via the link arm 12, the valve lift amount is transmitted to the swing cam 9 and the valve lifter 8 via the link rod 13. The lift amount increases rapidly from the zero lift to the maximum lift side, and the operating angle that is the valve opening period also increases.

  Further, by changing the phase of the control cam 18 according to the vehicle running load, the lift amount of the intake valve 4 can be arbitrarily controlled between the zero lift (valve stop) and the maximum lift (maximum operating angle). For example, the lift curve of the intake valve 4 shown in FIG. 8 can be changed. These series of controls are performed continuously.

  The throttle valve 07 is normally maintained in a substantially fully opened state, and the required air amount to the combustion chamber 06 is mainly controlled by the first intake air VEL1 and the second intake air VEL1 '.

  As the first intake VTC 2, a known one using a hysteresis brake described in Japanese Patent Application Laid-Open No. 2004-156508, for example, previously filed by the present applicant is used.

  This is because an assembly angle changing means for changing the assembly angle between the drive ring on the crankshaft side and the driven shaft member on the drive shaft 6 side is interposed, and the assembly angle changing means is installed in the engine. The control unit 22 outputs a control current to the electromagnetic coil according to the state of the vehicle including the driving state, and controls the hysteresis brake to control the lift phase of the intake valves 4, 4, that is, the opening / closing timing of the intake valves 4, 4. Is controlled to advance or retard. The VTC may be a vane type that converts the phase by hydraulic pressure instead of the hysteresis brake.

  The first exhaust VVL3 of the right bank RB has the same structure as that described in, for example, Japanese Patent Laid-Open No. 10-8935, and briefly described, as shown in FIG. 6 and FIG. A maximum lift high-speed cam 31 provided for each cylinder on the shaft 30, provided on both sides of the high-speed cam 31, and supported by a zero lift cylindrical cams 32, 32 and a rocker shaft 33 so as to be swingable. The main rocker arm 34 is disposed at a position corresponding to both the cylindrical cams 32, 32, and the lower end of each tip is in contact with the stem ends of the exhaust valves 5, 5. The sub rocker arm 35 capable of lost motion, the lost motion mechanism 36 provided at the lower portion of the sub rocker arm 35, and the support shaft fixed to the main rocker arm 34. 7, a lever member 38 that is supported so as to be swingable and engages / disengages with a lower end portion of the sub rocker arm 35 to synchronize or cancel the sub rocker arm 35 and the main rocker arm 34, and the lever member A hydraulic plunger 39 and a return spring 40 for engaging and disengaging 38 are provided.

  The hydraulic plunger 39 is moved backward by an oil pressure supplied from an oil pump 46 to an oil chamber 41 formed on the outer peripheral side via hydraulic passages 41a and 41b formed in the rocker shaft 32 and the sub rocker arm. It moves forward by the spring force of the coil spring 42 mounted inside. Further, the electromagnetic switching control valve 43 switches the conduction between the hydraulic passages 41 a and 41 b and the drain passage 44 or the discharge hydraulic pressure of the oil pump 46. The switching control valve 43 is switched by a control current output from the control unit 22.

  Hereinafter, the operation of the first exhaust VVL3 will be briefly described. For example, when the vehicle load increases and changes to a state in which the vehicle should be driven by the internal combustion engine, the control unit 22 that detects the change causes the switching control valve. Since the power supply to 43 is cut off, the hydraulic passages 41a and 41b are conducted to the drain passage 44, so that the hydraulic pressure is reduced.

  Therefore, as shown in FIG. 7B, the hydraulic plunger 39 moves forward by the spring force of the coil spring 42, and rotates the lever member 38 counterclockwise against the spring force of the return spring 40. The tip of the member 38 engages with the lower jaw on the tip side of the sub rocker arm 35 during the base circle of the high-speed cam 31 to interlock the sub rocker arm 35 and the main rocker arm 34.

  As a result, the main rocker arm 34 swings in accordance with the cam profile of the high-speed cam 31, so that the exhaust valves 5 and 5 are controlled to be switched to the maximum lift (see the upper left side in FIG. 8). Thereby, the vehicle can be driven by the internal combustion engine.

  On the other hand, for example, when the electric motor 52 shifts to a low load range to be traveled, the switching control valve 43 is operated to supply the discharge hydraulic pressure of the oil pump 46 into the oil chamber 41, as shown in FIG. 7A. As described above, the hydraulic plunger 39 moves backward against the spring force of the coil spring 42. As a result, the lever member 38 is rotated in the opposite direction by the spring force of the return spring 40 to release the connection between the sub rocker arm 35 and the main rocker arm 34, whereby the sub rocker arm 35 enters a lost motion state. For this reason, the main rocker arm 34 does not receive the lift force of the high-speed cam 31 and only comes into sliding contact with the cylindrical cams 30 and 30, and the lift amount of the exhaust valves 5 and 5 becomes zero lift. As a result, the valve is stopped, and the intake valves 4 and 4 are also in the valve stopped state, so that the cylinder is stopped (see the upper right side in FIG. 8).

  As described above, the first exhaust VVL3 is configured to switch the lift amount of the exhaust valves 5 and 5 on and off between zero lift and high lift.

  The structure of the second intake VEL1 ′ on the left bank LB side is the same as that of the first intake VEL1 on the right bank RB side, and the second intake VEL1 ′ also has a valve lift amount of the intake valves 4 and 4. Control is continuously performed from zero lift (valve stop) to the maximum lift amount, and the same action as the first intake VEL1 is obtained.

  Since the structure of the second intake VTC 2 ′ is the same as that of the first intake VTC 2, the detailed description is omitted. In addition, the opening and closing timing of the intake valves 4 and 4 is also controlled to advance or retard.

  Since the second exhaust VVL3 ′ has the same configuration as the first exhaust VVL3, a detailed description thereof will be omitted.

  Hereinafter, a specific operation by the control unit 22 of the present embodiment, that is, control for each vehicle driving region will be described based on the flowchart of FIG.

  In step 1, the current driving state of the vehicle is read from the accelerator opening, the vehicle speed, the motor current of the engine speed electric motor 52, and the like by various sensors.

  In step 2, a target travel load value Lt (driving force) is calculated from the read accelerator opening, vehicle speed, and the like.

  In step 3, it is determined whether or not the target travel load value Lt is smaller than the predetermined load value L2. If it is determined that the target travel load value Lt is equal to or greater than L2, the process proceeds to step 11, where The intake / exhaust valves 4 and 5 of all the cylinders RB and LB are operated (all cylinder operation mode) and burned in all the cylinders to generate a large torque from the internal combustion engine 51. Alternatively, it is possible to assist the motor by supplying a current to the electric motor 52. Specifically, the inverter 58 is controlled to convert a direct current from the battery 59 into an alternating current by the inverter 58, and then a current is supplied to the electric motor 52.

  When the torque by the internal combustion engine 51 is sufficient with respect to Lt, the throttle valve 07 is not throttled, but the throttle valve 07 is set to a large opening and the closing timing of the intake valve 4 is set to the bottom dead center of the piston. If the torque control is performed by shortening the suction stroke before the pumping loss is reduced, the fuel consumption can be reduced.

  If it is determined in step 3 that the target travel load value Lt is less than the large load value L2, the process proceeds to step 4.

  In step 4, it is determined whether or not the target travel load value Lt is smaller than the medium load value L1. In this step 12, the three cylinders on the right bank RB side are stopped (partially cylinder stop mode), and the combustion is controlled only on the left bank LB side (reducing cylinder operation).

  Stopping the three cylinders on the right bank RB side means that the first intake VEL1 and the first exhaust VVL3 on the right bank RB side are controlled to zero lift, thereby confining gas in the cylinder (combustion chamber). As a result, there is no gas exchange, there is no pumping loss, and no fuel is injected from the fuel injection valve 08.

  On the other hand, on the left bank side where the intake / exhaust valves 4 and 5 are operating (operating), the combustion load of the operating cylinder increases due to the reduced cylinder operation, so that the pumping loss is reduced and the combustion is improved. In addition, the thermal efficiency itself increases. Therefore, the fuel consumption of the internal combustion engine 51 can be greatly reduced as compared with the all cylinder operation.

  In the present embodiment, when one bank is stopped, the RB side is always selected. Therefore, the operation bank is fixed to the LB side, so the performance is stable. Conversely, stop banks RB and LB can be selected as appropriate. In this way, the performance can be improved by making the bank with excellent performance an active bank.

  Further, here, the throttle valve 07 is maintained at a large opening without being throttled, and the torque is controlled by shortening the suction stroke by controlling the closing timing of the intake valve 04 before the bottom dead center. Since the pumping loss is further reduced, it is possible to suppress the consumption of combustion.

  When the driving by the internal combustion engine 51 is less than the target travel load value Lt, it is also possible to supply current to the electric motor 52 and use this driving force as an assisting force as described above.

  If it is determined in step 4 that the target travel load value Lt is smaller than the medium load value L1, the process proceeds to step 5, where an SOC (State of Charge) that is an index of the amount of charge of the battery 59 is read. .

  Next, in step 6, it is determined whether or not the charged amount SOC is larger than the predetermined amount S2. If it is determined that the stored amount SOC is large, in step 7, the operation (operation) of the intake and exhaust valves 4 and 5 of all cylinders is performed. Control to stop.

  That is, the first and second intake VEL1, 1 ′ and the first and second exhaust VVL3, 3 ′ of all cylinders of the left and right banks RB, LB are controlled to zero lift (valve closed state). As a result, gas is confined in the cylinder, which eliminates gas exchange, thereby reducing the pumping loss, and thus reducing the rotational friction of the crankshaft 51a of the internal combustion engine 51. In addition, since fuel injection is not performed, the loss caused by the internal combustion engine 51 is significantly reduced, and the vehicle is driven by the highly efficient electric motor 52. Therefore, the fuel efficiency of the vehicle as a whole is improved.

  If it is determined in step 6 that the storage amount SOC is less than S2, the process proceeds to step 8. Here, it is determined whether or not the charged amount SOC is further greater than the allowable minimum value S1, and if it is determined that it is less than S1, the routine proceeds to step 9.

  In Step 9, all cylinder operating modes, that is, all cylinders in the left and right banks RB and LB are controlled to be in a combustion operation on the assumption that the charged amount is insufficient. That is, the vehicle is driven by the internal combustion engine 51 in the all-cylinder combustion operation and the electric motor 52 is rotationally driven. Accordingly, the electric motor 52 works as a generator, and power generation is started, and the battery 59 is charged via the inverter 58. In this case, since all cylinders are operated, maximum charging is performed.

  On the other hand, if it is determined in step 8 that the charged amount SOC is greater than the allowable minimum value S1, the process proceeds to step 10 because the charging is slightly insufficient. In Step 10, the operation of the three cylinders on the right bank side is stopped, the three cylinders on the left bank side are operated, and the reduced cylinder operation is performed. Then, the vehicle is driven by the internal combustion engine 51 in the reduced cylinder operation, and the electric motor 52 is driven to rotate. As a result, the electric motor 52 acts as a generator to start power generation, and the battery 59 is charged via the inverter 58. In this case, since it is a reduced-cylinder operation, the fuel consumption of the internal combustion engine 51 is reduced, and it is possible to achieve both charging operation and improved fuel efficiency.

[Control Mode 2 of Control Unit 22]
FIG. 10 is a flowchart showing different controls by the control unit 22, and the acceleration of the vehicle is started from the state where the traveling load of the vehicle is small and all the cylinders of the internal combustion engine 1 are stopped only by the power of the electric motor 52. The control when it is performed is shown.

That is, the electric motor 52 and the transmission 54 are connected by the second clutch 55, and the driving force of the electric motor 52 is transmitted to the transmission 54. The operation of the cylinder is stopped and traveling control by the electric motor 52 is performed.

  In step 21, the driving state of the vehicle is read based on the accelerator opening, etc., as described above. Next, in step 22, a target travel load value (driving force) Lt is calculated.

  In step 23, it is determined whether or not the target travel load value Lt is greater than a predetermined load value L2.

  In this step 24, all the cylinders of the internal combustion engine 51 are changed to an operating state. That is, the intake / exhaust valves 4 and 5 of all cylinders that have been stopped until now are changed to the normal lift operation via the first and second intake VELs 12, 1 'and 2' and the first and second exhaust VVLs 3 and 3 '. To do. However, combustion injection is not performed at this time.

  Next, when the first clutch 53 is not connected, in step 25, the first clutch 53 is connected, the internal combustion engine 51 and the electric motor 52 are interlocked, and the process proceeds to step 26.

  In this step 26, the electric motor 52 cranks the internal combustion engine 51, and simultaneously with this cranking, the fuel is injected from the fuel injection valve, and the ignition plug is energized to start the internal combustion engine 51 and complete explosion. Let After this complete explosion, in step 27, all cylinders shift to normal combustion. As a result, the output torque of the internal combustion engine 51 is increased to realize a favorable acceleration of the vehicle. Here, the switching of each variable mechanism in step 24 and the control of the first clutch 53 may be reversed. When the first clutch 53 is connected in advance, this connection control process is omitted.

  On the other hand, if it is determined in step 23 that the target travel load value Lt is smaller than L2, the process proceeds to step 28. In this step 28, it is determined whether or not Lt is smaller than the allowable minimum value L1. If it is determined that it is greater than or equal to L1, that is, if it is determined that the load is moderate (acceleration), the routine proceeds to step 29. In step 29 and thereafter, one-bank operation stop control is finally performed, but the following control is performed in order to improve startability and acceleration.

  That is, in step 29, the operation is changed to the operation of all cylinders of the internal combustion engine 51. Next, the process proceeds to step 30 where a process of connecting the first clutch 53 is performed. However, when the first clutch 53 is connected in advance, the process is omitted.

  In step 31, when complete explosion control of the internal combustion engine 51 is performed, cranking is performed by the electric motor 52, and fuel injection control and ignition timing control are performed.

  In step 32, all the cylinders are brought into operation, and assist drive control by the electric motor 52 is performed.

  As described above, if all cylinders are operated (started) from the beginning, the number of explosions increases, so the starting torque increases and the internal combustion engine 51 rises faster. In particular, as described above, the first and second intake air VEL1, 1 ′ and the first and second intake air VTC2, 2 ′ are closed at the default position (mechanical position) near the bottom dead center of the piston. Therefore, the effective compression ratio is high, and the ignitability is also good in that sense. As a result, a reliable and speedy start can be achieved.

  Therefore, since the explosion completes satisfactorily and the rotation rises quickly, the time until the internal combustion engine 51 can drive the vehicle is shortened, and the acceleration response is improved.

  Thereafter, in step 33, it is determined whether or not the predetermined time Δt has elapsed based on the timer. If it is determined that the predetermined time has elapsed, the process proceeds to step 34. In this step 34, only the three cylinders of the left bank LB of the internal combustion engine 51 are operated, the operation of the three cylinders of the right bank RB is stopped, and a reduced cylinder operation corresponding to a medium load is performed. As a result, fuel efficiency can be improved as compared with the case of all cylinder operation.

  Therefore, in the case of moderate acceleration, it is possible to satisfy both good acceleration response and good fuel efficiency.

  If it is determined in step 28 that the Lt is smaller than the allowable minimum value L1, the operation state is in the low load range, so the routine proceeds to step 35 where the all-cylinder stop mode is continued and the electric motor The vehicle continues to be driven only at 52.

  The lift curves of the intake / exhaust valves 4 and 5 in the operation of all cylinders in steps 29 to 32 are as shown on the left side of FIG. That is, in both banks LB and RB, the intake valves 4 and 4 have a small lift and a small operating angle by the intake VELs 1 and 1 ', and are controlled to advance by the intake VTCs 2 and 2'. Becomes sufficiently earlier than the bottom dead center of the piston. Here, the lift amount Lr2 of the right bank RB≈the lift amount L12 of the left bank LB, and the lift time area Sr2 of the right bank RB≈the lift time area S12 of the left bank LB. In this case, since the intake air amount (torque) is controlled by the intake stroke, the throttle valve 07 is hardly required to be throttled, so that the pumping loss is small and the fuel efficiency is improved.

  Next, when shifting to the reduced cylinder operation (step 34) as described above, as shown on the right side of FIG. 8, the right bank RB stops the cylinder operation, while the left bank LB determines the lift amount of the intake valve 4. It increases (Ll3) and the lift time area also increases (Sl3).

  Here, the second intake VTC 2 ′ is also operated to control the closing timing of the intake valve 4 earlier than the bottom dead center so that the throttle valve 07 does not have to be throttled as in the case of all cylinder operation. And fuel economy has improved.

  Furthermore, in the reduced-cylinder operation, the engine torque equivalent to the all-cylinder operation operation can be ensured even though the combustion cylinder is halved. This is because the lift amount Ll3 of the left bank LB, which is the operating cylinder in the reduced cylinder operation, is larger than the lift amounts Ll2, Lr2 of the left and right banks LB, RB in the all cylinder operation operation, and the intake air amount (torque) per cylinder is larger. Large, so the engine torque is equal.

  The lift time area S13 of the left bank LB in the reduced cylinder operation is about twice the lift time area S12 in the all cylinder operation operation. From this point of view, the intake air amount (torque) as seen in the internal combustion engine 51 as a whole is both This is the same level for all cylinder operation and reduced cylinder operation.

  As for the intake pipe pressure, as shown in FIG. 8, the throttle valve 07 is almost fully open and close to the atmospheric pressure in both the reduced cylinder and all cylinder operations. Therefore, since there is no intake pipe pressure difference before and after switching, transient torque fluctuation due to intake pipe pressure transient change is suppressed. As a result, there is an advantage that the switching shock can also be suppressed.

[Control Mode 3 of Control Unit 22]
FIG. 11 shows a control flow chart by the control unit 22 when the decelerating operation is performed by coasting or braking from the medium load traveling in the reduced cylinder operation.

  That is, when the vehicle is traveling in the state of medium load L1 to L2, in step 31, the current vehicle traveling state is detected by reading an information signal such as the accelerator opening, and the step is performed based on this detection signal. In 32, a target travel load value (driving force) Lt is calculated.

  In step 33, it is determined whether or not the target value Lt is smaller than a predetermined medium load value L1. If it is determined that the target value Lt is greater than or equal to L1, the process is terminated. In step 34, the operation of all cylinders in the left and right banks LB and RB is stopped. Since engine brakes are difficult to operate when all cylinders stop operating, it becomes possible to operate a larger regenerative brake (motor power generation) with the electric motor 52, and the battery 59 can be sufficiently charged via the inverter 58. it can.

  After that, after deceleration, the control proceeds to step 35 where the vehicle is driven by the driving force of the electric motor 52.

  On the other hand, at this time, the first clutch 53 remains connected to the crankshaft 51a of the internal combustion engine 51 and the motor shaft 52a, and the rotation of the engine has not stopped. Therefore, when re-acceleration becomes necessary, the engine torque can be easily generated by switching the variable mechanism such as the first intake VEL1 to the all-cylinder operating state and performing the complete explosion control, thereby realizing quick acceleration. .

  However, if the connection of the first clutch 53 is continued, the crankshaft 51a of the internal combustion engine 51 continues to idle, so that the friction is applied.

  Accordingly, in step 36, it is determined whether or not the predetermined time T1 has elapsed after all cylinders have stopped operating. If it is determined that the predetermined time T1 has elapsed, the vehicle load is stable in the region below L1. In step 37, the connection of the first clutch 53 is disconnected (released). This reduces the friction and further improves the fuel consumption.

  Thereafter, in step 38, the variable mechanism such as the first intake VEL1 is switched to the all-cylinder operation mode. In this case, the internal combustion engine 51 is hardly rotating and filing is not performed. In this way, when all cylinders are in advance, all cylinders can start and complete when a situation where it is desired to re-accelerate. As described above, good startability and good reacceleration Can be secured.

[Control Mode 4 of Control Unit 22]
FIG. 12 shows a control flowchart of the control unit 22 when the vehicle is stopped, that is, when the vehicle speed is zero.

  In step 41, the current driving state is read based on the information signal such as the accelerator opening, and in step 42, it is determined whether or not the vehicle is stopped.

  If it is determined that the vehicle is in a stopped state, in step 43, the current charged amount (charge amount SOC) of the battery 59 is read from the charge sensor.

  In step 44, it is determined whether or not the charged amount SOC is larger than a predetermined value S2. If it is determined that the stored amount SOC is larger, the process proceeds to step 45.

  In step 45, the operation of all the cylinders in the left and right banks LB and RB of the internal combustion engine 51 is stopped, and the second clutch 55 is connected. That is, the vehicle can be driven at any time by the driving force of the electric motor 52.

  On the other hand, if it is determined in step 44 that the storage amount SOC is less than the predetermined value S2, the routine proceeds to step 46, where it is determined whether or not the storage amount SOC is larger than the allowable minimum value S1.

  If it is determined that it is less than S1, the connection of the second clutch 55 is disconnected in step 47 to release the connection between the motor shaft 52a and the output shaft 54a of the transmission 54 and the combustion of the left and right banks LB and RB is performed. That is, control is performed to operate all cylinders. Therefore, the electric motor 52 is rotated via the first clutch 53 and the battery 59 is charged via the inverter 58 by the generator function of the electric motor 52. As described above, since charging is performed with a large torque in the all-cylinder operation operation, the charging efficiency is increased, and the storage amount SOC is rapidly increased.

  On the other hand, if it is determined in step 46 that the charged amount SOC is larger than S1, the process proceeds to step 48, where the second clutch 55 releases the connection between the motor shaft 52a and the output shaft 54a and the right bank. Charging is performed by stopping the cylinder on the RB side and performing control (reducing cylinder operation) to operate the cylinder on the left bank LB side. Since this reduced-cylinder operation consumes less fuel, charging can be performed while suppressing deterioration in fuel consumption.

[Second Embodiment]
FIG. 13 shows a second embodiment in which the arrangement of the electric motor 52, the first clutch 53, the second clutch 55, and the like is changed, and the first clutch 53 and the electric motor 52 are arranged on one side of the internal combustion engine 51. And the inverter 58 are arranged in series, and the second clutch 55 is arranged on the rear end side of the internal combustion engine 51.

  The internal combustion engine 51 is a V-type 6 cylinder as in the first embodiment, and is formed with 3 cylinders each in the left and right banks RB and LB.

  The first clutch 53 is configured such that a rotational force is transmitted via a drive belt 60 from a projecting end 51 b of a crankshaft 51 a projecting forward of the internal combustion engine 51, and this rotational force is transmitted to the electric motor 52. The transmission or the transmission is cut off.

  The electric motor 52 also functions as a starter motor for the internal combustion engine 51 as in the first embodiment, and current is supplied from the battery 59 via the inverter 58.

  The second clutch 55 receives a rotational force directly from the crankshaft 51 a, and transmits or interrupts the rotational force to the transmission 54.

  Other configurations are the same as those in the first embodiment, and the internal combustion engine 51 and the electric motor 52 are intermittently connected by the first clutch 53. The electric motor 52 and the transmission 54 are intermittently connected by the second clutch 55 as in the first embodiment, but the first clutch 53 and the crankshaft of the internal combustion engine 51 exist in the middle of the transmission path. Therefore, the first clutch 53 can also be provided with the on / off function of the second clutch 55.

  Therefore, this embodiment can obtain the same operation effect as that of the first embodiment, and the electric motor 52, the first clutch 53, and the inverter 58 are arranged on the side portion of the internal combustion engine 51 in parallel with the internal combustion engine 51 and in series. Since it is arranged in the state, the axial length of the entire apparatus can be shortened, and the layout of the vehicle in the axial direction is improved.

  The present invention is not limited to the configuration of each of the above embodiments, and can be applied to, for example, an in-line four-cylinder engine other than the V type as an internal combustion engine, and switches between all cylinder operation stop, front two cylinder stop, and all cylinder operation. It is also possible to do so. In addition to a gasoline engine, a diesel engine may be used. Furthermore, it is possible to apply to a compression ignition engine instead of spark ignition by a spark plug.

  Further, the specific mechanisms of VEL1 and VEL1 'are not particularly limited, and for example, another continuous variable lift mechanism as described in JP-A-2006-200391 may be used. Furthermore, instead of stopping both the intake and exhaust valves, the cylinder can be stopped by stopping one of the intake and exhaust valves and changing the other open / close center (phase center) to the bottom dead center. There may be. By doing so, it is possible to stop the cylinder by substantially stopping the cycle of the internal combustion engine.

  Further, the present invention can be applied to a device without the first and second clutches.

It is a whole lineblock diagram showing the vehicle control device of a 1st embodiment of the present invention. It is a schematic diagram of an internal-combustion engine provided for this embodiment. It is a perspective view which shows the 1st intake VEL and 1st intake VTC which are provided to this embodiment. A and B are explanatory diagrams of operation at the time of zero lift control by the first intake VEL. A and B are operation explanatory diagrams at the time of large lift control by the intake VEL. It is a perspective view which shows the exhaust VVL provided to this embodiment. A is an operation explanatory diagram at the time of zero lift control by the exhaust VVL, and B is an operation explanatory diagram at the time of high lift control. It is a characteristic view which shows the lift change of the intake valve and exhaust valve in this embodiment. It is a flowchart by the control unit provided to this embodiment. It is a flowchart which shows the different control by the same controller. It is a flowchart which shows further different control by the same control unit. It is a flowchart which shows further different control by the same control unit. It is a whole block diagram of the vehicle control apparatus of 2nd Embodiment.

Explanation of symbols

RB ... right bank LB ... left bank 1 ... first intake VEL (intake side variable mechanism)
2 ... 1st intake VTC (intake phase variable mechanism)
1 '... 2nd intake VEL (intake side variable mechanism)
2 '... 2nd intake VTC (intake phase variable mechanism)
3. First exhaust VVL (exhaust lift variable mechanism)
3 '... 2nd exhaust VVL (exhaust lift variable mechanism)
DESCRIPTION OF SYMBOLS 4 ... Intake valve 5 ... Exhaust valve 6 ... Drive shaft 7 ... Drive cam 9 ... Swing cam 11 ... Rocker arm 12 ... Link arm 13 ... Link rod 17 ... Control shaft 18 ... Control cam 19 ... Drive mechanism 20 ... Drive motor 22 ... Control unit 31 ... High speed cam 32 ... Cylinder cam 33 ... Rocker shaft 34 ... Main rocker arm 35 ... Sub rocker arm 51 ... Internal combustion engine 52 ... Electric motor 53 ... First clutch 54 ... Transmission 55 ... Second clutch

Claims (18)

A vehicle control device for controlling a vehicle including an internal combustion engine having a plurality of cylinders as a power source,
An all-cylinder stop mode for stopping the operation of the intake valves and exhaust valves of all cylinders of the internal combustion engine;
A partial cylinder stop mode for stopping the operation of the intake valve and the exhaust valve of the partial cylinder of the internal combustion engine;
An all-cylinder operation mode for operating intake valves and exhaust valves of all cylinders of the internal combustion engine;
Is switched according to the driving state of the vehicle. The vehicle control device according to claim 1,
In the all-cylinder stop mode, the vehicle travels by the driving force of the electric motor. The vehicle control device according to claim 2,
In the low load region of the vehicle, the vehicle is driven by the electric motor controlled to the all cylinder stop mode,
In the middle load range of the vehicle, the partial cylinder stop mode is controlled to travel by the internal combustion engine,
A vehicle control device that is controlled by the all-cylinder operation mode and travels by the internal combustion engine in a high load range of the vehicle. In the vehicle control device according to claim 3,
When changing from the low load range to the medium load range, the internal combustion engine is started by temporarily switching from the all-cylinder stop mode to the all-cylinder operation mode, and then switched to the partial cylinder stop mode. Vehicle control device. The vehicle control device according to claim 1,
The internal combustion engine includes a variable mechanism that varies the operating angle of the intake valve,
The vehicle control apparatus, wherein the variable mechanism is controlled so that the operating angle of the intake valve is larger in the partial cylinder stop mode than in the full cylinder operation mode. The vehicle control device according to claim 2,
A first clutch is provided between a crankshaft of the internal combustion engine and an output shaft of the electric motor;
The vehicle control device, wherein the first clutch is connected when the internal combustion engine is started. The vehicle control device according to claim 6,
The vehicle control device characterized in that the first clutch is disengaged when a low load state or a stopped state of the vehicle is continued for a predetermined time. The vehicle control device according to claim 6,
When the vehicle is in a low load state or stopped state for a predetermined time, the first clutch is disengaged and the internal combustion engine is stopped in a state where the operation of the intake valve and the exhaust valve is switched to the all-cylinder operation mode. A vehicle control device. The vehicle control device according to claim 2,
A first clutch is provided between the crankshaft of the internal combustion engine and the output shaft of the electric motor;
Immediately after the vehicle is braked, the vehicle control device switches to the all-cylinder stop mode and connects the first clutch. The vehicle control device according to claim 9, wherein
Comprising a mechanism for regenerating by the electric motor and charging the battery;
A vehicle control device characterized in that regeneration is performed by the electric motor immediately after the vehicle is braked. In the vehicle control device according to claim 3,
A vehicle control device characterized in that, when the storage amount of the battery is equal to or less than a predetermined value, the vehicle is driven by an internal combustion engine without switching to the all-cylinder stop mode even if the vehicle is in a low load state. In the vehicle control device according to claim 3,
A second clutch is provided between the output shaft of the electric motor and the transmission and / or between the crankshaft of the internal combustion engine and the transmission;
A vehicle control device characterized in that, when the amount of electricity stored in the battery is equal to or less than a predetermined value when the vehicle is stopped, the second clutch is disengaged and the internal combustion engine is driven. In the vehicle control device according to claim 3,
When the battery charge level is greater than or equal to a predetermined value in a low load state of the vehicle, all cylinders are stopped. When the battery charge level is less than the predetermined value and exceeds the allowable minimum value, some cylinders are stopped. The vehicle control apparatus according to claim 1, wherein when the value is equal to or less than the allowable minimum value, the control is performed in an all-cylinder operation mode. The vehicle control device according to claim 5, wherein
The vehicle control apparatus characterized in that the variable mechanism continuously changes the lift amount and the operating angle of the intake valve. The vehicle control device according to claim 1,
The vehicle control apparatus according to claim 1, wherein the exhaust valve of the internal combustion engine is provided with lift switching means for switching between an opening / closing operation state and a valve closing state. The vehicle control device according to claim 1,
The internal combustion engine is configured as a V-type, and the partial cylinder stop mode stops the operation of an intake valve and an exhaust valve arranged in one V-type bank. A vehicle control device for controlling a vehicle including an internal combustion engine having a plurality of cylinders as a power source and an electric motor,
An all-cylinder stop mode in which all cylinders of the internal combustion engine are stopped and driven by the driving force of the electric motor;
A partial cylinder stop mode in which some cylinders of the internal combustion engine are stopped;
An all-cylinder operating state in which all cylinders of the internal combustion engine operate;
Is switched according to the driving state of the vehicle. A vehicle control device for controlling a vehicle including an internal combustion engine having a plurality of cylinders as a power source,
An all-cylinder stop mode for stopping all cylinders of the internal combustion engine;
A partial cylinder stop mode in which some cylinders of the internal combustion engine are stopped;
An all-cylinder operating state in which all cylinders of the internal combustion engine operate;
To switch according to the driving state of the vehicle,
In order to start the internal combustion engine from the all-cylinder stop mode, it is controlled to switch from the all-cylinder stop mode to the all-cylinder operation mode, and further to switch from this all-cylinder operation mode to the partial cylinder stop mode. Vehicle control device.

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