JP2001140665A - Power source control device for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve efficiency of regenerative power generating of an electric motor by an engine brake by opening and closing operations of intake/exhaust valves of an internal combustion engine at the time of deceleration of a vehicle. SOLUTION: In a section 1, the present request deceleration signal outputted from a stepping speed detection sensor is read. When it is discriminated that a hydraulic brake mechanism is not out of order, battery charging amount is below a prescribed value and request deceleration is below a prescribed value in sections 2 to 4, a lift varying means is controlled to a null lift characteristic in a section 5. In sections 6, 7, an electric motor is cut in current supply, functions as a power generator by rotation of a front wheel, performs regenerative power generation and performs a charging action by supplying the regenerative current to a battery.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention utilizes both the power of an ordinary internal combustion engine and the power of an electric motor as a power source of a vehicle, and controls both power sources appropriately according to the operating state of the vehicle. And a power source control device for a vehicle.

[0002]

2. Description of the Related Art As is well known, recently, in vehicles such as passenger cars, a power source is set to a power of a general gasoline internal combustion engine due to a demand for reducing environmental pollution by exhaust gas and improving fuel efficiency. A motor that uses both powers of an electric motor and appropriately controls both powers according to a driving state of a vehicle is provided. As an example, a motor shown in FIG. 12 is known.

[0003] In brief, a 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 generated by a power split mechanism using planetary gears to generate a driving force to wheels and the like. Machine driving force.

That is, a gasoline internal combustion engine 54 and an electric motor 55 are connected to an axle 53 of the front wheels 51 and 52 via a speed reducer 56, and an output shaft 54a of the internal combustion engine 54.
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 disposed between the transmission shaft 57 that is the input shaft of the speed reducer 56 and the transmission shaft 57. Have been. 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 an operation region 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.

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

Further, for example, when the vehicle is accelerated by suddenly 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, and the driving force is further increased. Increase.

When the vehicle is decelerated or the driver depresses the brake pedal to brake the vehicle,
Is turned off or stopped, that is, only the piston or the like is operated without supplying fuel to the combustion chamber, or the operation of the piston or the like is stopped, while the wheels 51 and 52 are stopped.
Drives 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, the power of the internal combustion engine 54 is basically used as the power source of the vehicle. However, when the vehicle starts or travels at a very low speed, the power of the electric motor 55 alone is used. At times, the electric motor 55 assists the power of the internal combustion engine 54, so that the fuel efficiency of the internal combustion engine 54 can be improved and the environmental deterioration due to the reduction of the amount of exhaust gas can be improved.

[0010]

However, in the above-described conventional power source control apparatus for a vehicle, when the vehicle is decelerated or braked, the internal combustion engine 54 is idling or stopped while the wheels are stopped. Since the 51 and 52 drive the electric motor 55 to function as a generator and generate regenerative electric power, 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 braking Acts to reduce the rotation of the wheels 51 and 52, 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. In this case, however, the throttle valve flows into the combustion chamber from the intake port via the intake valve. Cold air passes through the exhaust catalyst from the exhaust pipe through the exhaust valve as it is, and the exhaust catalyst is cooled. For this reason,
The purification capacity of the exhaust catalyst is reduced, and then the internal combustion engine 5
Exhaust gas emission performance when the combustion of No. 4 starts is reduced.

In the case where the internal combustion engine 54 is stopped, it takes a long 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. there were.

[0014]

SUMMARY OF THE INVENTION The present invention has been devised in view of the technical problems of the conventional power source control device for a vehicle, and the invention according to claim 1 is based on the power and electric power of an internal combustion engine. In a power source control device for a vehicle that controls the power of a motor in accordance with a driving state of a vehicle, a lift variable unit that variably controls a valve lift amount of an engine valve of the internal combustion engine, a brake mechanism that brakes the vehicle, Request deceleration detection means for detecting a driver's request deceleration at the time of braking of the vehicle; and when the request deceleration value detected by the request deceleration detection means is equal to or less than a predetermined value, the engine valve is lifted. Zero lift converting means for controlling to zero lift by the variable means, and when the required deceleration value is equal to or less than a predetermined value, the kinetic energy transmitted from the wheels is converted to electric energy by the power generation action of the electric motor. It is characterized by comprising a regenerative converter means for.

Therefore, according to the present invention, during braking of the vehicle, if the driver's required deceleration is equal to or less than a predetermined value, the valve lifts of the intake valves and exhaust valves serving as engine valves are controlled to zero lift. As a result, the valve is stopped, that is, fully closed, so that gas exchange loss due to the intake and exhaust valves is avoided, and so-called engine braking is less likely to be applied.
As a result, the deceleration of the wheels by the internal combustion engine is suppressed, and the recovery efficiency of the regenerative electric energy by the electric motor increases.

According to a second aspect of the present invention, when the required deceleration value detected by the required deceleration detection means exceeds a predetermined value, the zero lift control of the engine valve by the zero lift conversion means is released. It is characterized in that zero lift canceling means is provided.

Therefore, when the driver performs, for example, a sudden braking operation, a normal opening and closing operation, that is, a pump operation by gas exchange is performed without performing zero lift control on the engine valve. In addition, since the engine brake is also operated, a strong braking force is obtained.

According to a third aspect of the present invention, there is provided a charge state detecting means for detecting a charge state of a battery for supplying electric power to the electric motor, and the charged amount of the battery detected by the charge state detecting means is a predetermined value. If the required deceleration value exceeds the predetermined deceleration value, the zero lift control is released by the zero lift release means even if the required deceleration value is equal to or less than a predetermined value.

According to the present invention, it is possible to prevent excessive recovery of regenerative power by the electric motor while securing a desired battery charge amount.

According to a fourth aspect of the present invention, a failure detecting means for the brake mechanism is provided, and when a failure detection signal is output from the brake failure detecting means, the failure is not more than the required deceleration value. The zero lift control is released by the zero lift release means.

According to the present invention, at the time of failure of the brake mechanism due to normal hydraulic pressure or the like, at least engine braking can be secured.

A fifth aspect of the present invention is characterized in that the engine valve is controlled to zero lift by the zero-lift conversion means immediately before stopping the driving of the internal combustion engine.

According to the present invention, since the friction of the valve train at the time of restarting the internal combustion engine can be reduced, good restartability or good vehicle starting performance can be obtained.

The invention according to claim 6 is characterized in that the valve lift of the engine valve is continuously variably controlled by the lift variable means in accordance with the engine operating state.

According to the present invention, when the valve lift of the engine valve is controlled, for example, from the maximum lift to the zero lift, the change in the lift can be continuously and gradually reduced, so that the sudden change in the operation of the engine brake can be achieved. Can be prevented, and a stable braking feeling can be obtained.

According to a seventh aspect of the present invention, the variable lift means rotates in synchronization with the crankshaft of the engine and is supported swingably on 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. And a control cam for changing the maximum value of the lift amount of the engine valve by the swing cam, and an electric actuator for rotating a control shaft for controlling a 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. As a result, the regenerative electric power can be effectively used, and a separate hydraulic drive source and hydraulic drive mechanism are not required.

[0028]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a power source control device for a vehicle according to the present invention will be described below in detail with reference to the drawings.

The power source control device for a vehicle according to the present embodiment comprises:
As shown in FIG. 1, a pair of front wheels 2a, 2b and rear wheels 3a, 3b provided at the front and rear of the vehicle body 1, and a four-cylinder gasoline internal combustion engine 5 for transmitting power to the front wheels 2a, 2b via an axle 4. An electric motor 6 for driving the front wheels 2a and 2b together with or separately from the power of the internal combustion engine 5, and an intake valve 12 which is an engine valve and an exhaust valve (not shown) provided in each cylinder of the internal combustion engine 5. Lift variable means 7 for controlling each valve lift according to the engine operating state;
b, 3a, 3b, and a hydraulic brake mechanism 8 for braking the two power sources, and a controller 9 for appropriately controlling 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.

As shown in FIG. 2, the internal combustion engine 5 is provided with a lift mechanism 7 on a valve operating mechanism provided on a cylinder head 11. For convenience, a description will be given of an example applied to the intake valve 12 side.
Are rotatably supported by two intake valves 12 and exhaust valves per cylinder which open and close intake and exhaust ports by sliding in the cylinder head 11 via a valve guide (not shown) and a bearing 14 on the upper part of the cylinder head 11. A hollow drive shaft 13,
One drive cam 15, which is an eccentric rotary cam fixed to the drive shaft 13, is swingably supported by the outer peripheral surface 13 a of the drive shaft 13, and is disposed at the upper end of each intake valve 12. A swing cam 17 that slides on the valve lifters 16, 16,
A transmission mechanism 18 linked between the drive cam 15 and 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 mechanism 19.

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

The bearing 14 is provided at the upper end of the cylinder head 11 and supports the upper part of the drive shaft 13. The main bracket 14a is provided at the upper end of the main bracket 14a to rotate a control shaft 32 to be described later. And a sub-bracket 14b for supporting freely.
a and 14b are fixed together from above by a pair of bolts 14c and 14c.

As shown in FIG. 4, the drive cam 15 is integrally formed of a wear-resistant material, and has an annular cam portion 15a.
And a cylindrical portion 15b integrally provided on the outer end surface of the cam portion 15a. A drive shaft insertion hole 15c is formed through the drive shaft through hole 15c in the internal axial direction. Is offset from the axis X by a predetermined amount in the radial direction. The drive cam 15 is connected and fixed to the drive shaft 13 by a connection pin 40 inserted from the diametric 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 cylindrical shape with a lid, are slidably held in holding holes of the cylinder head 11, and have cam bodies 17a, 17a of the swing cam 17, which will be described later, slide. Contact upper surface 16a, 16a
Are formed flat.

As shown in FIGS. 2 and 3, 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 portion 20, Support hole 20a formed in the inner axial direction of base end portion 20
Are supported in a freely swingable manner on a drive shaft 13 through which a cam hole is inserted, and a pin hole is formed through a cam nose portion 21 provided on one end side. Also, each cam body 17a
A cam surface 22 is formed on each of the lower surfaces of the cam surface 22. The cam surface 22 includes a base circular surface 22a on the base end portion 20 side and a ramp surface 22b extending in an arc shape from the base circular surface 22a to the cam nose portion 21 side. And a lift surface 22c extending from the ramp surface 22b to the top surface 22d of the maximum lift provided on the tip end side of the cam nose portion 21. The base circle surface 22a, the ramp surface 22b, the lift surface 22c, and the top surface 22d are formed. Abuts on a predetermined position of the upper surface 16a of each valve lifter 16 in accordance with the swing position of the swing cam 17.

That is, in view of the valve lift characteristics shown in FIG. 5, the predetermined angle range θ1 of the base circular 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. And a predetermined angle range θ3 from the ramp section θ2 of the ramp surface 22b to the top surface 22d is set to be a 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 the drive shaft 13 has a central hole 34a.
It is fitted and held.

The transmission mechanism 18 includes a rocker arm 23 disposed above the drive shaft 13, a link arm 24 for linking one end 23a of the rocker arm 23 and the drive cam 15, and a bifurcated other end of the rocker arm 23. A link rod 25 for linking the portion 23b and the swing cam 17 is provided.

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 to be described later via a support hole 23d. One end 23a protruding from the outer end of the cylindrical base 23c.
Each of the other end portions 2 projecting from the inner end portion of the base portion 23c has a pin hole through which the pin 26 fits.
3b is formed with a pin hole through which a pin 27 connected to one end 25a of the link rod 25 is fitted.

The link arm 24 has a base end 24a, which is a relatively large-diameter annular end, and a base end 2a.
And a projecting end 24b which is the other end protruding at a predetermined position on the outer peripheral surface of the drive cam 15 at the center position of the base end 24a via a needle bearing 34 on the outer peripheral surface of the cam portion 15a of the drive cam 15. The protruding end 24b is formed with a pin hole through which the pin 26 is rotatably inserted. One end 23a of the rocker arm 23 is
It is a pivot point.

Further, as shown in FIG. 2, the link rod 25 is formed in a substantially rectangular shape in which the rocker arm 23 is concave, and the other end 23b of the rocker arm 23 and the cam body 17a are formed 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 of the cam nose portion 21 are rotatably inserted.

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. Of the link rod 25 and the rocker arm 2
3 and the cam nose portion 21 of the swing cam 17
It is a pivot point.

A needle as a rolling bearing member is provided between the cam portion 15a of the driving 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. Bearing 35 is interposed. The needle bearing 35 is provided in the annular holder 3.
5a 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 formed on one side of the driving cam and one side of the holding member 34. , In the direction of the drive shaft 13. Here, the driving cam 15 is also connected to the holding member 3.
4 is also formed of a wear-resistant material, so that even if it slides on the retainer 35a, occurrence of wear is suppressed.

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

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

The control cam 33 has a cylindrical shape.
As shown in the figure, 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 has 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, and from a battery 41 power supply via an inverter 40. , A current converted from direct current to alternating current is supplied.
Further, the drive of the electric motor 6 is controlled by an output signal from the controller 9 via an inverter 40 and the front wheels 2a, 2
b functions as a generator by the torque of b, converts regenerative power from AC to DC through an inverter 40, and
1.

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

The controller 9 detects the current engine operating state by calculation or the like based on detection signals from various sensors such as a crank angle sensor, an air flow meter, and a water temperature sensor, and determines the rotational position of the control shaft 32. A control signal is output to the electric actuator 29 according to a detection signal from the potentiometer 31 to be detected. 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,
It is determined whether the current required deceleration is equal to or less than a predetermined value.

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

First, zero lift control will be described.
The control shaft 32 is rotated clockwise through the electromagnetic actuator 29 by a control signal from the controller 9. For this reason, the control cam 33 holds the shaft center P1 at the upper left rotation angle position from the shaft center P2 of the control shaft 32 as shown in FIG.
It moves away to the a side. For this reason, the rocker arm 23
The entire body moves in the upper left direction with respect to the drive shaft 13, so that the cam bodies 17a, 17a are forcibly pulled up on the cam nose portion 21 side via the link rod 25, and are entirely rotated in the counterclockwise direction. .

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

Therefore, as shown in FIG. 9, since the valve lift amount becomes zero, friction is reduced, gas exchange loss is avoided, and so-called engine braking is hardly applied. As a result, when the deceleration is controlled to such a zero lift, the recovery efficiency of the regenerative electric energy by the electric motor 6 increases. Alternatively, by controlling the lift to zero during steady-state running at low speed, driving the vehicle with only the electric motor 6 can 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 the number of revolutions of the engine increase, fuel is supplied to the internal combustion engine 5 by a control signal from the controller 9 and the worm gear 36 is driven by the electromagnetic actuator 29. ,
The control shaft 32 is driven to rotate counterclockwise via 37. 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. For this reason, the rocker arm 23 moves in the direction of the drive shaft 13 (downward) as a whole, and the other end 23 b pushes the cam nose portion 21 of the swing cam 17 downward via the link rod 25 to cause the swing. The entire moving cam 17 is rotated clockwise by a predetermined amount.

Accordingly, 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. Especially at high rotation and 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, the controller 9 controls the lift variable means 7 during braking of the vehicle and controls the electric motor 6.
Will be described based on the 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 battery 41 from the charge state detection sensor 46 is read. Read charging status of. 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 amount 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 this 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 low-load operation, and the thick portion 33a of the control cam 33 is largely moved from the drive shaft 13 to the pivot point 26a as shown in FIG. . Accordingly, 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, gas exchange is not performed, and excessive cooling of the exhaust catalyst due to cold fresh air is prevented, so that the purification performance of the exhaust catalyst is prevented from lowering.

Next, in section 6, processing for cutting off the supply of current to the electric motor 6 is performed.
Starts the operation as a generator, but performs an efficient regenerative power generation as a generator because the engine brake is less likely to be applied as described above. 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, in section 5, the intake valve 1
After performing zero lift control of section 2, in section 8,
In order to realize the required deceleration, the present required hydraulic braking force other than the regenerative braking force by the electric motor 6 is calculated. 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 adjustment 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.

In section 2, when it is determined that the hydraulic brake mechanism 8 is out of order, in section 3, when it is determined that the battery charge amount exceeds a predetermined value, further, in section 4, the demand is reduced. When it is determined that the speed exceeds the predetermined value, the process proceeds to section 10 respectively. The failure of the hydraulic brake mechanism 8 is determined by comparing the detected 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 performed at the zero lift, but is performed in a normal lift characteristic according to the engine operating state, or in a case where the normal lift characteristic is the zero lift. A process of controlling the rotational position of the control shaft 32 via the electric actuator 29 so as to achieve predetermined lift characteristics is performed. Here, the predetermined lift characteristic is a lift characteristic in which the intake valve is closed when the engine brake is easily applied near the bottom dead center of the piston.

Therefore, for example, the hydraulic brake mechanism 8
In the event of a failure, at least the braking force by the engine brake can be secured, so that the safety is enhanced. Also, even when the battery charge exceeds a predetermined value, the processing of section 10 does not exert the function of the electric motor 6 as a generator and does not generate regenerative power. The operation is suppressed to improve the durability and prevent the battery from overcurrent. 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 is generated by the engine brake. Can be done.

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

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

Next, the control by the controller 9 when stopping the driving of the internal combustion engine 5 will be described with reference to the flowchart shown in FIG. In other words, in the case of sudden braking in which the required deceleration exceeds a predetermined value, since the vehicle is not controlled to zero lift as described above, when the vehicle is stopped or the key is turned off in such a state, the following is performed. Internal combustion engine 5
This is an improvement since the startability deteriorates due to the high lift at the start of the vehicle.

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 vehicle speed exceeds the predetermined value, the process returns to section 21. If it is determined that the value is equal to or smaller than the predetermined value, the process proceeds to 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, proceeding to section 24, it is determined whether or not the current valve lift is actually zero 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, so that the friction of the valve train becomes extremely small and good startability can be 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 be reduced.
As shown in FIG. 9, it is possible to obtain continuous characteristics from the maximum lift to zero lift. 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.

Further, by adopting the above-described structure of the lift variable means 7, it is possible to greatly change the valve lift amount from zero to the maximum lift, whereby the output of the engine 5 can be improved. Good power performance is also obtained.

Further, since the electric actuator 29 is used as a driving means for driving the control shaft 32 of the variable mechanism 8 to rotate, it can be driven by 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 or the like in the case of a hydraulic actuator is not required, which is advantageous in terms of cost.

In this embodiment, since the needle bearing 35 is interposed between the drive cam 15 and the base end 24a of the link arm 24, the outer peripheral surface 15 of the cam 15a is formed.
d and the coefficient of friction μ between the inner peripheral surface 24c of the base 24a 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 rotational 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.

The present invention is not limited to the configuration of the above-described embodiment. For example, a predetermined support shaft on which the swing cam 17 swings may be different from the drive shaft. It is needless to say that if the drive shaft is also used as in the embodiment, the number of parts can be reduced and the device can be made compact.

[0081]

As is apparent from the above description, claim 1
According to the described invention, during braking of the vehicle, if the driver's required deceleration is equal to or less than a predetermined value, the valve lifts of the intake valves and the exhaust valves serving as the engine valves are controlled to zero,
Since the valve is in a stopped state, that is, in a fully closed state, friction is reduced, and gas exchange loss caused by the intake and exhaust valves is avoided, and so-called engine braking is hardly applied. As a result, the deceleration of the wheels by the internal combustion engine is suppressed, and the recovery efficiency of the regenerative electric energy by the electric motor increases.

Further, since no gas exchange is performed, excessive cooling of the exhaust catalyst is prevented, and a decrease in the purification performance of the exhaust catalyst is prevented.

According to the second aspect of the present invention, when the driver performs, for example, a sudden braking operation, the engine valve is not controlled to zero lift, that is, the pump is operated by gas exchange. Since the engine brake is also activated in addition to the braking, a strong braking force is obtained.

According to the third aspect of the present invention, it is possible to prevent the regenerative electric power from being excessively recovered by the electric motor while securing a desired battery charge amount.

According to the fourth aspect of the present invention, it is possible to secure at least engine brake when the brake mechanism fails due to normal hydraulic pressure or the like.

According to the fifth aspect of the invention, since the friction of the valve train at the time of restarting the internal combustion engine can be reduced, good restartability or good startability of the vehicle can be obtained.

According to the sixth aspect of the invention, when the valve lift of the engine valve is controlled, for example, from a high lift to a zero lift, the change in the lift can be continuously and gently reduced. Operation change can be prevented, and a stable brake feeling can be obtained.

According to the seventh aspect of the present invention, the valve lift of the engine valve can be controlled to be sufficiently large from zero lift to high lift, and the use of the electric actuator allows the use of the regenerative electric power. Since it can be operated, the regenerative electric power can be effectively used, and a separate hydraulic drive source and a hydraulic drive mechanism are not required.

[Brief description of the drawings]

FIG. 1 is an overall schematic diagram showing an embodiment of the present invention.

FIG. 2 is a view as viewed from the direction indicated by the arrow A in FIG. 3, showing a variable lift means provided in the embodiment of the present invention.

FIG. 3 is a perspective view of a main part of the lift variable means.

FIG. 4 is a perspective view of a drive cam provided to the variable lift means.

FIG. 5 is a profile characteristic diagram of a cam surface of an oscillating cam provided to a variable lift unit.

FIG. 6 is a partial cross-sectional view of the lift variable means.

FIG. 7 is a view indicated by an arrow A in FIG. 3 showing an opening / closing operation state of an intake valve during minimum valve lift (zero lift) control.

FIG. 8 is a diagram showing an opening and closing operation state of the intake valve at the time of maximum valve lift control, as indicated by an arrow A in FIG. 3;

FIG. 9 is a valve lift characteristic diagram of the embodiment.

FIG. 10 is a flowchart illustrating control by a controller during vehicle braking.

FIG. 11 is a flowchart illustrating control by a controller when the internal combustion engine is stopped.

FIG. 12 is a schematic diagram showing a conventional power source control device for a vehicle.

[Description of Signs] 1 ... Car body 2a, 2b ... Front wheels 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

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[Procedure amendment]

[Submission date] November 29, 1999 (1999.11.
29)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name]

[Correction method] Change

[Correction contents]

Therefore, for example, the hydraulic brake mechanism 8
In the event of a failure, at least the braking force by the engine brake can be secured, so that safety is enhanced. Also, even when the battery charge exceeds a predetermined value, the processing of section 10 does not allow the electric motor 6 to function as a generator and prevent regenerative power generation from occurring. and improvement in durability operation is suppressed, preventing a battery from being overcharged can be achieved. 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 is generated by the engine brake. Can be done.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI theme coat ゛ (reference) F02D 13/02 F02D 29/02 D 29/02 B60K 9/00 EFterm (reference) 3G092 AA11 AC02 CB02 CB05 DA01 DA02 DA05 DG03 DG08 EA01 EA04 EA08 EA15 EA22 FA15 FA25 FA32 FA34 FA50 FB09 GA10 GB08 HA01Z HA13X HE03Z HE08Z HF02Z HF26Y HF26Z 3G093 AA07 AA16 BA19 CA02 CB00 CB14 DA05 DA07 DA19 EC01 DB15 QE10 QI04 QI09 RB08 RE20 SE05 TB01 TE08 TI01 TO02 TO24 TR19 TU02

Claims (7)

[Claims] 1. A power source control device for a vehicle for controlling the power of an internal combustion engine and the power of an electric motor in accordance with an operating state of a vehicle, wherein a lift variable means for variably controlling a valve lift of an engine valve of the internal combustion engine. A braking mechanism for braking the vehicle, a required deceleration detecting means for detecting a required deceleration of the driver at the time of braking the vehicle, and a required deceleration value detected by the required deceleration detecting means is equal to or less than a predetermined value. In the case of the above, the zero lift conversion means for controlling the engine valve to zero lift by the lift variable means, and when the required deceleration value is equal to or less than a predetermined value, the kinetic energy transmitted from the wheels to the electric motor A power source control device for a vehicle, comprising: a regenerative conversion means for regenerating electric energy by a power generation action of the vehicle. 2. A zero lift release means for releasing the zero lift control of the engine valve by the zero lift conversion means when the required deceleration value detected by the required deceleration detection means exceeds a predetermined value. The power source control device for a vehicle according to claim 1, wherein: And a charge state detecting means for detecting a state of charge of a battery for supplying a current to the electric motor, and when a charge amount of the battery detected by the charge state detector exceeds a predetermined value. 3. The power source control device for a vehicle according to claim 2, wherein the zero lift control is released by the zero lift release means even if the required deceleration value is equal to or less than a predetermined value. 4. A brake failure detection means is provided, and when a failure detection signal is output from the brake failure detection means, the zero lift release is performed even if the required deceleration value is equal to or less than a predetermined value. 4. The power source control device for a vehicle according to claim 2, wherein the zero lift control is canceled by the means. 5. Immediately before stopping driving of the internal combustion engine,
The power source control device for a vehicle according to any one of claims 2 to 4, wherein the engine valve is controlled to zero lift by the zero lift conversion means. 6. The power source control for a vehicle according to claim 2, wherein the variable lift means continuously and variably controls a valve lift amount of the engine valve according to an engine operating state. apparatus. 7. The variable lift means rotates in synchronization with the crankshaft of the engine, is supported by a drive shaft having a drive cam provided on the outer periphery thereof, and is swingably supported by a predetermined support shaft. An oscillating cam for opening the engine valve against a spring force, a transmission mechanism for transmitting the rotational force of the drive shaft to the oscillating cam as oscillating power, and changing the attitude of the transmission mechanism to the oscillating cam. 7. A control cam for changing a maximum value of a lift amount of an engine valve by the control cam, and an electric actuator for rotationally driving a control shaft for controlling a rotation position of the control cam. A power source control device for a vehicle according to any one of claims 1 to 3.