JP2004251285A - Power source control device for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the starting performance of a vehicle while securing the favorable starting performance of an internal combustion engine by zero-lift control when the engine is stopped. <P>SOLUTION: When an ignition switch is determined as being in an on-state in a section 21, whether a vehicle speed is a prescribed value or lower is determined in a section 22. When it is determined to exceed the prescribed value, the section 21 is repeated. When it is determined to be the prescribed value or lower, a control signal is outputted to an electric actuator 29 to control valve lift characteristics of an intake valve 12 for zero lift in a section 23. When it is determined that the zero lift is actually achieved based on a signal from a potentiometer in a section 24, a signal to stop the driving of the internal combustion engine is outputted in a section 25, and the engine is stopped in a section 26. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

  The present invention uses a power source of both a normal internal combustion engine and an electric motor as a power source of a vehicle, and controls both power sources appropriately according to the driving state of the vehicle. About.

  As is well known, recently, in vehicles such as passenger cars, due to demands such as reduction of environmental pollution due to exhaust gas and improvement of fuel efficiency, a power source is provided between a power of a general gasoline internal combustion engine and a power of an electric motor. One that uses both of them and appropriately controls both powers according to the driving state of the vehicle is provided, and an example thereof is shown in FIG. 12.

  In brief, the power source control device for a vehicle basically uses an internal combustion engine as the power, and the power of the internal combustion engine is controlled by a power split mechanism using planetary gears to drive the wheels and the like, and to drive the generator. Divided into forces.

  That is, the gasoline internal combustion engine 54 and the electric motor 55 are connected to the axle 53 of the front wheels 51 and 52 via the reduction gear 56, and the output shaft 54a of the internal combustion engine 54 and the transmission shaft 57 which is the input shaft of the reduction gear 56. A power split mechanism 58 that mechanically distributes the power of the internal combustion engine 54 to the driving force of the transmission shaft 57 and the driving force of the generator by a planetary gear is provided between the power split mechanism 58 and the power generating mechanism 58. The power split device 58 is connected to a generator 61 that supplies power for storing electricity to the battery 59. The electric motor 55 is supplied with a drive current from a battery 59 via an inverter 60.

  In a driving range where the power efficiency of the internal combustion engine is low, such as when the vehicle starts or when the vehicle is running at a very low speed, the vehicle is driven by the power of the electric motor 55.

  Also, during normal running, the power of the internal combustion engine 54 is divided into two paths by the power split mechanism 58, one of which directly drives the wheels 51 and 52, the other of which drives the generator 61, and The electric motor 55 is driven to assist the driving force of the internal combustion engine 54.

  Further, for example, when the vehicle is accelerated by fully opening the throttle valve at the time of rapid acceleration or the like, electric power is supplied to the electric motor 55 from the battery 59 in addition to the generator 61 to further increase the driving force. .

  Further, when the vehicle is decelerated or the driver depresses the brake pedal to perform braking, the internal combustion engine 54 is idled or stopped, that is, only the piston or the like is operated without supplying fuel to the combustion chamber, or While the operation of the piston and the like is also stopped, the wheels 51 and 52 drive the electric motor 55 to act as a generator to generate regenerative electric power, and the collected electric energy is stored in the battery 59.

As described above, basically, the power of the internal combustion engine 54 is used as the power source of the vehicle. However, when the vehicle starts or when the vehicle is traveling at a very low speed, the power of the electric motor 55 alone is used. By assisting the power of the engine 54 with the electric motor 55, it is possible to improve the fuel efficiency of the internal combustion engine 54 and improve the environmental deterioration due to the reduction of the exhaust gas amount.
JP-A-11-346402

  However, in the conventional power source control device for a vehicle, when the vehicle is decelerated or braked, the internal combustion engine 54 idles or stops, while the wheels 51 and 52 drive the electric motor 55, as described above. As a result, the regenerative electric power is generated by functioning as a generator, so that the following technical problems are caused.

  That is, first, when the internal combustion engine 54 is idling, a gas exchange loss due to opening and closing of the intake valve and the exhaust valve of the internal combustion engine 54, that is, a pumping loss due to pumping occurs, and a so-called engine brake operates accordingly. As a result, the rotation of the wheels 51 and 52 is reduced, and as a result, the efficiency of regenerative power generation by the electric motor 55 is reduced.

  Therefore, in order to reduce the gas exchange loss as much as possible, it is conceivable to further open the throttle valve fully, but in this case, the cool air flowing into the combustion chamber from the intake port via the intake valve this time is not changed. The exhaust catalyst passes through the exhaust pipe through the exhaust pipe via the exhaust valve, and is cooled. For this reason, the purification ability of the exhaust catalyst is reduced, and the exhaust gas emission performance when the combustion of the internal combustion engine 54 is started next time is reduced.

  In the case where the internal combustion engine 54 is stopped, there is a problem that it takes time to start the internal combustion engine 54 at the time of re-acceleration and further increase the rotation, and thus the response of the re-acceleration is poor.

  The present invention has been devised in view of the technical problem of the conventional power source control device for a vehicle, and the invention according to claim 1 has an advantage that the driving of the internal combustion engine is stopped before the driving of the internal combustion engine is stopped. The engine valve is controlled to zero lift by lift variable means for variably controlling the valve lift amount of the engine valve, and when the vehicle starts, the electric motor is started to operate, and after the electric motor starts to operate, the internal combustion engine is started. It is controlled to start.

  According to the present invention, when the internal combustion engine is started, the valve lift is zero, so that the friction of the valve train is extremely small, and good startability is obtained.

  Further, the start of the internal combustion engine 5 is also performed when the electric motor starts driving and the vehicle starts, so that the startability of the vehicle is also improved.

  The invention according to claim 2 is characterized in that the valve lift amount of the engine valve is continuously variably controlled by the lift variable means according to the engine operating state.

  According to this invention, in addition to the operation and effect of the first aspect, when the valve lift of the engine valve is controlled from, for example, the maximum lift to zero lift, it is possible to continuously and smoothly reduce the change in the lift. Therefore, a sudden change in the operation of the engine brake can be prevented, and a stable braking feeling can be obtained.

  According to a third aspect of the present invention, the variable lift means rotates in synchronization with the crankshaft of the engine, and is swingably supported by a drive shaft provided with a drive cam on the outer periphery and a predetermined support shaft, A rocking cam for opening the engine valve against the spring force of the valve spring, a transmission mechanism for transmitting the rotational force of the drive shaft to the rocking cam as rocking power, and changing the posture of the transmission mechanism to change the posture of the transmission mechanism. It is characterized by comprising a control cam that changes the maximum value of the lift amount of the engine valve by the swing cam, and an electric actuator that rotationally drives a control shaft that controls the rotation position of the control cam.

  According to the present invention, the valve lift amount of the engine valve can be controlled to be sufficiently large from zero lift to high lift, and it can be operated by the regenerative electric power by using the electric actuator. Effective use of electric power can be achieved, and a separate hydraulic drive source and a hydraulic drive mechanism are not required.

  Hereinafter, an embodiment of a power source control device for a vehicle according to the present invention will be described in detail with reference to the drawings.

  A power source control device for a vehicle according to this embodiment includes a pair of front wheels 2a, 2b and rear wheels 3a, 3b provided in front and rear of a vehicle body 1 as shown in FIG. A four-cylinder gasoline internal combustion engine 5 for transmitting power, an electric motor 6 for driving the front wheels 2a, 2b together with the power of the internal combustion engine 5 or alone, and an engine valve provided for each cylinder of the internal combustion engine 5. Lift variable means 7 for controlling the valve lift of each of the intake valve 12 (see FIG. 2) and the exhaust valve (not shown) according to the operating state of the engine, and a hydraulic pressure for braking the front and rear wheels 2a, 2b, 3a, 3b. The vehicle includes a brake mechanism 8 and a controller 9 that appropriately controls the two power sources according to the driving state of the vehicle.

  The axle 4 is provided with a differential gear 10 for transmitting each power of the internal combustion engine 5 and the electric motor 6 to the front wheels 2a, 2b.

  In the internal combustion engine 5, as shown in FIG. 2, a lift mechanism 7 is provided in a valve operating mechanism provided on a cylinder head 11.

  For convenience, a description will be given of an apparatus applied to the intake valve 12 side. The lift variable means 7 slides in the cylinder head 11 via a valve guide (not shown) to open and close the intake / exhaust port. One intake valve 12 and one exhaust valve, a hollow drive shaft 13 rotatably supported by a bearing 14 above the cylinder head 11, and one drive cam 15, which is an eccentric rotary cam fixed to the drive shaft 13. A swing cam 17 slidably supported by an outer peripheral surface 13 a of the drive shaft 13 and slidingly contacting valve lifters 16, 16 provided at upper ends of the intake valves 12, 12; A transmission mechanism 18 linked to the swing cam 17 for transmitting the rotational force of the drive cam 15 as the swing power of the swing cam 17 and a variable mechanism 19 for varying the operating position of the transmission mechanism 18 are provided. Have.

  The drive shaft 13 is arranged along the longitudinal direction of the engine, and rotates from a crankshaft of the engine via a driven sprocket (not shown) provided at one end or a timing chain wound around the driven sprocket. The force is transmitted, and the rotation direction is set counterclockwise in FIG. The drive shaft 15 is formed of a high-strength material.

  The bearing 14 is provided at an upper end of the cylinder head 11 and supports an upper portion of the drive shaft 13. A main bracket 14 a is provided at an upper end of the main bracket 14 a and rotatably supports a control shaft 32 described later. And both brackets 14a, 14b are fixed together from above by a pair of bolts 14c, 14c.

  As shown in FIG. 4, the drive cam 15 is integrally formed of a wear-resistant material, and includes an annular cam portion 15a and a cylindrical portion 15b integrally provided on an outer end surface of the cam portion 15a. The drive shaft insertion hole 15c is formed in the axial direction, and the center Y of the cam portion 15a is offset from the axis X of the drive shaft 13 by a predetermined amount in the radial direction. Further, the drive cam 15 is connected and fixed to the drive shaft 13 by a connection pin 40 inserted from the diametrical direction. Further, as shown in FIG. 2, the drive cam 15 rotates in the counterclockwise direction (the direction of the arrow) in FIG.

  The valve lifters 16, 16 are formed in a closed cylindrical shape, are slidably held in holding holes of the cylinder head 11, and have upper surfaces 16 a with which cam bodies 17 a, 17 a of the swing cam 17 slidably contact. , 16a are formed flat.

  The swing cam 17 includes a pair of substantially raindrop-shaped cam bodies 17a, 17a integrally provided at both ends of a substantially cylindrical base end 20 as shown in FIGS. The whole is supported swingably on a drive shaft 13 inserted through a support hole 20a formed in the internal axial direction of 20, and a pin hole is formed through a cam nose portion 21 on one end side. . A cam surface 22 is formed on the lower surface of each cam body 17a, and the cam surface 22 is formed in a circular shape from the base circular surface 22a on the base end portion 20 side to the cam nose portion 21 side from the base circular surface 22a. A ramp surface 22b extending in an arc shape and a lift surface 22c extending from the ramp surface 22b to the top surface 22d of the maximum lift provided on the distal end side of the cam nose portion 21 are formed, and the base circular surface 22a, the ramp surface 22b, and the lift surface are formed. The upper surface 22 c and the top surface 22 d abut on a predetermined position on the upper surface 16 a of each valve lifter 16 according to the swing position of the swing cam 17.

  That is, from the viewpoint of the valve lift characteristics shown in FIG. 5, the predetermined angle range θ1 of the base circle surface 22a is a base circle section, and the predetermined angle range θ2 from the base circle section θ1 of the ramp surface 22b is a so-called ramp section. The predetermined angle range θ3 from the ramp section θ2 of the ramp surface 22b to the top surface 22d is set to be the lift section. An annular holding member 34 is provided between one end surface of the base end portion 20 of the swing cam 17 and the driving cam 15. As shown in FIG. 6, the holding member 34 has an outer diameter substantially equal to the outer diameter of the cylindrical portion 15b of the drive cam 15, and is fitted and held on the drive shaft 13 via the central hole 34a. .

  The transmission mechanism 18 includes a rocker arm 23 disposed above the drive shaft 13, a link arm 24 for linking one end 23 a of the rocker arm 23 and the drive cam 15, and a forked other end 23 b of the rocker arm 23. And a link rod 25 that links the swing cam 17.

  As shown in FIG. 2, the rocker arm 23 has a cylindrical base 23c provided at the center thereof rotatably supported by a control cam 33 described later via a support hole 23d. A pin hole into which the pin 26 fits is formed through one end 23a protruding from the outer end of the cylindrical base 23c, while the other end protruded from the inner end of the base 23c. A pin hole into which a pin 27 connected to one end 25a of the link rod 25 is fitted is formed through the end 23b.

  Further, the link arm 24 has a base end 24a which is a relatively large-diameter annular end, and a projecting end 24b which is the other end protruding at a predetermined position on the outer peripheral surface of the base end 24a. A fitting hole 24c is formed at a central position of the base end portion 24a so as to be rotatably fitted to an outer peripheral surface of the cam portion 15a of the driving cam 15 via a needle bearing 34, while a protruding end is provided. A pin hole through which the pin 26 is rotatably inserted is formed through the pin 24b. The axis 26a of the pin 26 is a pivot point with the one end 23a of the rocker arm 23.

  As shown in FIG. 2, the link rod 25 is formed in a substantially rectangular shape in which the rocker arm 23 is concave. The other end 23b of the rocker arm 23 and the cam nose of the cam body 17a are provided at both ends 25a and 25b. Pin insertion holes 25c and 25d through which the ends of the pins 27 and 28 press-fit into the respective pin holes 21 are rotatably inserted are formed.

  One end of each of the pins 26, 27, 28 is provided with a snap ring (not shown) for restricting the movement of the link arm 24 and the link rod 25 in the axial direction. Reference numerals 27a and 28a serve as pivot points between the two ends 25a and 25b of the link rod 25, the other end 23b of the rocker arm 23, and the cam nose 21 of the swing cam 17.

  A needle bearing 35 as a rolling bearing member is provided between the cam portion 15a of the drive cam 15 and the inner peripheral surface 24c of the base end portion 24a of the link arm 24 fitted to the outer peripheral surface 15d of the cam portion 15a. It is interposed. The needle bearing 35 includes an annular holder 35a and a plurality of needle rollers 35b rotatably held by the holder 35a.

  As shown in FIG. 2, the needle bearing 35 is entirely held by the outer peripheral surface of the cam portion 15a, and both end edges of the holder 35a are driven by one side of the driving cam and one side of the holding member 34. It is clamped in the direction of the shaft 13. Here, since both the driving cam 15 and the holding member 34 are formed of a wear-resistant material, the occurrence of abrasion is suppressed even when the driving cam 15 and the holding member 35a slide.

  The variable mechanism 19 includes a control shaft 32 rotatably supported by the same bearing 14 at a position above the drive shaft 13, a control cam 33 fixed to the outer periphery of the control shaft 32 and serving as a swing fulcrum of the rocker arm 23. It has.

  The control shaft 32 is disposed in the engine front-rear direction in parallel with the drive shaft 13 as shown in FIG. 2, and is electrically driven via a worm wheel 36, which is a worm gear provided at one end, and a worm gear 37. By 29, it rotates within a predetermined rotation angle range.

  The control cam 33 has a cylindrical shape, and as shown in FIG. 2, the position of the axis P1 is deviated by α from the axis P2 of the control shaft 32 by the thickness portion 33a.

  The electric actuator 29 for controlling the rotation of the control shaft 32 is driven by a control signal from the controller 9 for detecting the operating state of the engine, as shown in FIG.

  The electric motor 6 is connected to the differential gear 10 via a motor output shaft 38a, while being connected to a transmission 39 provided at one end of the internal combustion engine 5 via a motor input shaft 38b. A current converted from DC to AC is supplied from a power supply of a battery 41 via an inverter 40. Further, the driving of the electric motor 6 is controlled by an output signal from the controller 9 via an inverter 40, and the electric motor 6 functions as a generator by the rotational force of the front wheels 2a, 2b. The power is converted from an alternating current to a direct current via an inverter 40 and supplied to a battery 41.

  Further, the hydraulic brake mechanism 8 generates a hydraulic pressure by depressing a brake pedal 42 to supply a hydraulic pressure to each wheel cylinder of the front and rear wheels 2a, 2b, 3a, 3b. A hydraulic pressure adjusting unit 44 composed of a pressure increasing / reducing valve, a hydraulic pump, and the like for adjusting the hydraulic pressure supplied from the cylinder 43 to each wheel cylinder, and control for controlling the operation of the pressure increasing / reducing valve of the hydraulic pressure adjusting unit 44. The circuit 45 is mainly configured. The hydraulic brake mechanism 8 is controlled by the controller 9 via a control circuit 45.

  The controller 9 detects a current engine operating state based on detection signals from various sensors such as a crank angle sensor, an air flow meter, a water temperature sensor and the like by calculation and the like, and detects a rotational position of the control shaft 32. A control signal is output to the electric actuator 29 based on a detection signal from the controller 31. The controller 9 detects the current state of charge of the battery 41 based on a detection signal from the state-of-charge detection sensor 46. Further, a required hydraulic braking force signal is output to the control circuit 45 based on a required deceleration signal from a depression speed detection sensor 47 for detecting the depression speed of the brake pedal 42 and a detection signal from the G sensor 48, and the current It is determined whether the required deceleration is equal to or less than a predetermined value.

  In the following, the operation of the present embodiment will be described. First, the basic control of the lift variable means 7 by the controller 9 will be briefly described.

  First, the zero lift control will be described. The control shaft 32 is driven to rotate clockwise through the electromagnetic actuator 29 by a control signal from the controller 9. For this reason, the control cam 33 is held at the rotation angle position where the axis P1 is at the upper left from the axis P2 of the control shaft 32 as shown in FIG. 7, and the thick portion 33a is located on the side of the pivot 26a from the drive shaft 13. Move away. As a result, the entire rocker arm 23 moves to the upper left with respect to the drive shaft 13, so that the cam bodies 17 a, 17 a are forcibly pulled up on the cam nose portion 21 side via the link rod 25, and Rotates counterclockwise.

  Therefore, as shown in FIGS. 7A and 7B, when the drive cam 15 rotates and pushes up one end 23 a of the rocker arm 23 via the link arm 24 during opening and closing operations of the intake valves 12, 12, the lift amount increases. Although transmitted to the swing cam 17 and the valve lifter 16 via the rod 25, the lift amount becomes zero.

  Therefore, as shown in FIG. 9, since the valve lift amount becomes zero lift, friction is reduced, gas exchange loss is avoided, and so-called engine braking is less likely to be applied. As a result, when the deceleration is controlled to the zero lift, the recovery efficiency of the regenerative electric energy by the electric motor 6 increases. Alternatively, if the lift is controlled to zero during steady-state running at low speed, the vehicle can be driven only by the electric motor 6 to improve fuel efficiency.

  At this time, the supply of fuel to the internal combustion engine 5 is interrupted by a control signal from the controller 9.

  On the other hand, in a normal engine operating state, as the load and rotation speed of the engine increase, fuel is supplied to the internal combustion engine 5 by a control signal from the controller 9 and the worm gears 36 and 37 are moved by the electromagnetic actuator 29. The control shaft 32 is rotated counterclockwise through the control shaft. Therefore, the control cam 33 rotates counterclockwise from the position shown in FIG. 7, and the axis P1 (thick portion 33a) moves downward as shown in FIG. Therefore, the rocker arm 23 moves in the direction of the drive shaft 13 (downward) as a whole, and the other end 23b pushes the cam nose portion 21 of the swing cam 17 downward via the link rod 25, thereby causing the rocker arm 23 to swing. The whole moving cam 17 is rotated clockwise by a predetermined amount.

  Therefore, the contact position of the cam surface 22 of each of the cam bodies 17a, 17a with the upper surface 16a of each of the valve lifters 16 moves to the rightward position (toward the lift portion 22d) as shown in FIGS. 8A and 8B. Therefore, when the drive cam 15 rotates to push up one end 23a of the rocker arm 23 via the link arm 24, the lift amount of the valve lifter 16 with respect to the valve lifter 16 increases. In particular, at a high rotation and a high load, the lift amount becomes the maximum value L2.

  Therefore, in such a high-speed and high-load region, as shown in FIG. 9, the valve lift becomes large, and the opening timing of each intake valve 12 is advanced and the closing timing is delayed. As a result, the intake charging efficiency is improved, and a sufficient output can be secured.

  Next, control of the lift variable means 7 and control of the electric motor 6 by the controller 9 during braking of the vehicle will be described with reference to a flowchart shown in FIG.

  First, when the brake pedal 42 is depressed by the driver, the current required deceleration signal output from the depression speed detection sensor 47 is read in section 1 and the state of charge of the battery 41 from the state-of-charge detection sensor 46 is read. Read. Subsequently, in section 2, it is determined whether or not the hydraulic brake mechanism 8 is out of order. If this is normal, the process proceeds to section 3, where it is determined whether or not the battery charge is equal to or less than a predetermined value. If it is determined that the battery charge is equal to or less than the predetermined value, it is determined in section 4 whether the required deceleration is equal to or less than the predetermined value. If it is determined in section 4 that the required deceleration is equal to or less than the predetermined value, the process proceeds to section 5.

  In this section 5, a control signal is output to the electric actuator 29 to control the lift variable means 8 to zero lift characteristics. That is, the electric actuator 29 controls the rotation of the control shaft 32 as in the case of the low-speed and low-load operation, and largely moves the thick portion 33a of the control cam 33 from the drive shaft 13 to the pivot point 26a as shown in FIG. . Therefore, the valve lift of the intake valve 12 (exhaust valve) has a zero lift characteristic as shown in FIG.

  Therefore, the friction is reduced, and the gas exchange loss due to the intake valve 12 is avoided, so that the so-called engine brake does not operate sufficiently. At this time, no gas exchange is performed, and excessive cooling of the exhaust catalyst by cold fresh air is prevented, and a decrease in the purification performance of the exhaust catalyst is prevented.

  Next, in section 6, a process of cutting off the current supply to the electric motor 6 is performed, and the electric motor 6 starts to function as a generator. However, as described above, it is difficult to apply the engine brake. Therefore, efficient regenerative power generation is performed as a generator. Subsequently, in section 7, a process of supplying the regenerative current to the battery 41 to perform a charging operation is performed.

  On the other hand, after the zero lift control of the intake valve 12 is performed in the section 5, in the section 8, in order to realize the required deceleration, the current required hydraulic braking force other than the regenerative braking force by the electric motor 6 is reduced. Calculate. Next, a required hydraulic brake force signal is output to the control circuit 45 of the hydraulic brake mechanism 8 in section 9. As a result, the hydraulic pressure adjusting unit 44 supplies a predetermined brake oil pressure to each wheel cylinder so that the required oil pressure braking force can be obtained, thereby achieving the required deceleration.

  Further, in the section 2, when it is determined that the hydraulic brake mechanism 8 is out of order, and in the section 3, it is determined that the battery charge amount exceeds a predetermined value, and further, in the section 4, the required deceleration becomes a predetermined value. If it is determined that the value is exceeded, the process proceeds to section 10 respectively. The failure of the hydraulic brake mechanism 8 is determined by comparing the detection value of the G sensor 48 with the required deceleration.

  In this section 10, the valve lift control of the intake valve 12 (exhaust valve) is not a zero lift, but a normal lift characteristic according to the engine operating state, or a forced lift when the normal lift characteristic is a zero lift. A process of controlling the rotational position of the control shaft 32 via the electric actuator 29 so as to achieve the lift characteristics described above is performed. Here, the predetermined lift characteristic is a lift characteristic in which the intake valve close timing is likely to be applied to the engine brake near the bottom dead center of the piston.

  Therefore, for example, at the time of failure of the hydraulic brake mechanism 8, at least the braking force by the engine brake can be secured, and the safety is enhanced. In addition, even when the battery charge exceeds a predetermined value, regenerative power generation is prevented from being generated by preventing the electric motor 6 from functioning as a generator by the above-described processing in section 10, so that the electric motor 6 The operation is suppressed, so that the durability can be improved and the battery can be prevented from being overcharged. Further, even when the required deceleration exceeds a predetermined value, that is, when a sudden braking operation is performed, the zero lift control of the intake valve 12 (exhaust valve) is not performed, so that a strong braking force by the engine brake is generated. Can be done.

  Further, when the process proceeds from the section 10 to the sections 11 and 12, in order to obtain the required deceleration, a process of securing the required hydraulic braking force by the hydraulic brake mechanism 8 as in the sections 8 and 9 is performed.

  The required deceleration signal is calculated and output in consideration of not only the output of the stepping speed detection sensor 47 but also the detection signal from the G sensor 48 and the vehicle speed signal from a vehicle speed sensor (not shown). Is also good. In that case, the driver's brake feeling is improved.

  Next, control by the controller 9 when stopping driving of the internal combustion engine 5 will be described based on a flowchart shown in FIG. That is, in the case of sudden braking in which the required deceleration exceeds a predetermined value, for example, the vehicle is not controlled to zero lift as described above. When the internal combustion engine 5 is started, the startability is deteriorated due to the high lift, and this is improved.

  First, in section 21, it is determined whether or not the ignition switch has been turned off. If it is determined that the ignition switch has been turned off, the process proceeds to section 23. If it is determined that the vehicle is still in the ON state, the process proceeds to section 22. Here, it is determined whether the vehicle speed is equal to or less than a predetermined value. If it is determined that the value is equal to or less than the value, the process proceeds to the section 23.

  In this section 23, a control signal is output to the electric actuator 29 so as to control the valve lift characteristic of the intake valve 12 (exhaust valve) to zero lift as described above. Then, proceed to section 24, where it is determined whether or not the current valve lift is actually zero lift based on the signal from the potentiometer 31. If the lift is not actually zero, the flow returns to the original state and the check is performed again. If the lift is zero, the process proceeds to section 25, where a signal for stopping the driving of the internal combustion engine 5 is output. Further, in section 26, the engine 5 is stopped.

  Therefore, when the internal combustion engine 5 is restarted, the valve lift is zero lift, so that the friction of the valve train becomes extremely small, and good startability is obtained. The start of the internal combustion engine 5 is also performed when the electric motor 6 starts operating and the vehicle starts, so that the startability of the vehicle is also improved.

  Further, according to the present embodiment, since the lift variable means 7 is configured as described above, the valve lift can have continuous characteristics from the maximum lift to zero lift as shown in FIG. . Therefore, when the deceleration request is detected by the stepping speed detection sensor 47, the lift gradually decreases when controlling to zero lift, so that a rapid change in engine brake can be suppressed. . As a result, a stable brake feeling can be obtained.

  In addition, since the lift variable means 7 is configured as described above, it is possible to greatly change the valve lift from zero to the maximum lift, thereby improving the output of the engine 5 and improving the power Performance is also obtained.

  Further, since the electric actuator 29 is used as a driving unit for driving the control shaft 32 of the variable mechanism 8 to rotate, the driving can be performed using the regenerative electric power obtained by the electric motor 6. As a result, the regenerative electric power can be effectively used, and a separate hydraulic drive mechanism in the case of a hydraulic actuator is not required, which is advantageous in terms of cost.

  In the present embodiment, since the needle bearing 35 is interposed between the drive cam 15 and the base end 24a of the link arm 24, the distance between the outer peripheral surface 15d of the cam portion 15a and the inner peripheral surface 24c of the base 24a is increased. Becomes sufficiently small. For this reason, not only can the driving cam 15 always rotate smoothly, but also the variation in the torque characteristics of the control shaft 32 can be prevented.

  As a result of the stabilization of the torque of the control shaft 32, the rotation position control of the control shaft 32 by the electric actuator 29 can be stabilized. For example, the lift control from the maximum lift region to the minimum lift region can be stabilized. Therefore, the valve lift control by the smooth and stable operation of the variable mechanism 19 according to the engine operating state can be obtained, and the engine performance can be sufficiently exhibited.

  Note that the present invention is not limited to the configuration of the above-described embodiment. For example, the predetermined support shaft on which the swing cam 17 swings may be different from the drive shaft. If the drive shaft is also used as described above, it goes without saying that the number of parts can be reduced and the device can be made compact.

1 is an overall schematic diagram showing an embodiment of the present invention. FIG. 4 is a view as viewed from an arrow A in FIG. The perspective view of the principal part of the same lift variable means. FIG. 4 is a perspective view of a drive cam provided to the lift variable unit. FIG. 4 is a profile characteristic diagram of a cam surface of an oscillating cam provided to a variable lift unit. FIG. 3 is a partial cross-sectional view of the lift variable unit. FIG. 4 is a diagram showing an opening and closing operation state of the intake valve during minimum valve lift (zero lift) control, as indicated by an arrow A in FIG. 3. FIG. 4 is a diagram illustrating an opening and closing operation state of an intake valve during maximum valve lift control, as indicated by an arrow A in FIG. 3. FIG. 4 is a valve lift characteristic diagram of the embodiment. FIG. 4 is a flowchart illustrating control of a controller during vehicle braking. FIG. 3 is a flowchart illustrating control by a controller when the internal combustion engine is stopped. The schematic diagram which shows the power source control apparatus of the conventional vehicle.

Explanation of reference numerals

DESCRIPTION OF SYMBOLS 1 ... Body 2a, 2b ... Front wheel 5 ... Internal combustion engine 6 ... Electric motor 7 ... Lift variable means 8 ... Hydraulic brake mechanism 9 ... Controller 12 ... Intake valve 13 ... Drive shaft 15 ... Drive cam 17 ... Swing cam 23 ... Rocker arm 24 ... Link arm 25 ... Link rod 31 ... Potentiometer 32 ... Control shaft 33 ... Control cam 41 ... Battery 42 ... Brake pedal 45 ... Control circuit 46 ... Battery charge detection sensor 47 ... Stepping speed detection sensor

Claims (3)

In a vehicle power source control device that controls the power of the internal combustion engine and the power of the electric motor according to the driving state of the vehicle,
Before stopping the drive of the internal combustion engine, while controlling the engine valve to zero lift by lift variable means for variably controlling the valve lift amount of the engine valve of the internal combustion engine,
A power source control device for a vehicle, wherein when the vehicle starts, the electric motor is started to operate, and after the electric motor is started, the internal combustion engine is controlled to start. The power source control device for a vehicle according to claim 1, wherein the lift variable means continuously and variably controls a valve lift amount of the engine valve according to an engine operation state. The lift variable means rotates in synchronization with the crankshaft of the engine, and is swingably supported by a drive shaft provided with a drive cam on the outer periphery and a predetermined support shaft, and resists the spring force of the valve spring. Swinging cam for opening the engine valve by means of a rotating mechanism, a transmission mechanism for transmitting the rotational force of the drive shaft to the swinging cam as swinging power, and changing the posture of the transmission mechanism to lift the engine valve by the swinging cam. 3. The vehicle power source according to claim 1, further comprising a control cam for changing a maximum value of the amount, and an electric actuator for driving a control shaft for controlling a rotation position of the control cam. Control device.

Images