JPH04330308A - Valve drive controller for engine - Google Patents

Abstract

PURPOSE:To enable complicate variable valve control of an engine in a real time manner with an electronic control system. CONSTITUTION:This controller is provided with electric drive means 3 open-close driving intake valves of an engine and the like and a displacement amplifier 4 amplifying and outputs displacement of the means 3 while being interposed between the means 3 and the intake valve and the like. The controller is also provided with engine speed measurement means 50 measuring engine speed, drive power source part 51 driving the means 3, and a main control part 53 controlling outputs of the drive power source part 51 via power source output control means 52 while being actuated according to the outputs of the means 50. The main control part 53 is provided with a memory in which a plurality of map data for control, and functions to select map data for optimum control at all times and to output specified selection command to power source output selection means according to the selection.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a valve drive control device for an engine, and more particularly to a valve drive control device for an engine which controls the opening and closing of an intake valve or an exhaust valve of an engine by electrical means.

0002

2. Description of the Related Art Generally, the intake valve or exhaust valve of an engine is mechanically opened and closed using a cam mechanism driven by the engine. In order to improve combustion efficiency and obtain large engine torque, we change the working angle of the cam to change the intake and exhaust volume depending on the situation.
A so-called variable valve mechanism is incorporated. As shown in Figure 18, methods for changing the working angle of the cam in a variable valve mechanism include: - changing the valve lift amount, - shifting the timing, and - changing the rocker arm to a cam with a different cross-sectional shape. things were being done.

[0003] Furthermore, JP-A-61-58909 and JP-A-60-128911 have been disclosed as electric valve operating devices using piezoelectric elements without using a cam mechanism.

0004

[Problems to be Solved by the Invention] However, in the above conventional example, the variable valve mechanism of the mechanical type is structurally fixed, and there are only two types of variable operation: low-speed rotation type and high-speed rotation type. Therefore, there was a problem in that fine valve control could not be performed in real time according to the operating conditions. On the other hand, those using piezoelectric elements did not perform variable valve control.

[0005]

OBJECTS OF THE INVENTION The object of the present invention is to improve the disadvantages of the conventional example, and in particular to perform complex variable valve control in real time using electronic control means using piezoelectric elements, etc. for engine intake valves, etc. An object of the present invention is to provide a valve drive control device for an engine.

[0006]

[Means for Solving the Problems] Accordingly, the present invention provides an electric driving means such as a laminated piezoelectric element that is displaced along the moving direction of the intake valve or exhaust valve of the engine and drives the intake valve or exhaust valve to open or close. , a displacement amplifier is interposed between the electric drive means and the intake valve or exhaust valve, and amplifies the displacement amount of the electric drive means by a predetermined factor to operate the intake valve or exhaust valve. An engine rotational speed measuring means for measuring the rotational speed, a driving power supply section for driving the electric drive means, and an output of the driving power supply section that operates based on the output of the engine rotational speed measuring means and via a power output control means. and a main control section that controls the level. In this main control section,
A map that includes a memory that stores a plurality of control map data for controlling the drive power supply unit, and allows the main control unit to select corresponding optimal control map data in accordance with fluctuations in the engine rotation speed measuring means. The system is configured to include a data selection function and an optimum control function for outputting a predetermined control command to the power output control means in real time based on the selected control map data. This aims to achieve the above-mentioned purpose.

[0007]

[Operation] ■The engine speed is measured by the engine speed measuring means and sent to the main control section.

[0008] The main control unit refers to map data, for example, of the relationship between the engine rotation speed and the cam operating angle, which is stored in advance in the memory attached to the main control unit, and calculates the measured engine rotation. The optimum operating time of the valve lift is calculated based on the cam operating angle corresponding to the number.

[0009] The main control section refers to the relationship map data stored in the memory between the engine speed and the voltage waveform applied to the electrical drive means such as the laminated piezoelectric element,
The optimum applied voltage waveform of the valve lift corresponding to the measured engine speed is calculated.

■The main control section refers to the relationship map data between the engine speed and the valve lift amount stored in the memory, and determines the optimum voltage value corresponding to the valve lift amount obtained from the engine speed. Desired. Then, the magnitude of the applied voltage and the application timing information obtained from the optimum voltage value and the optimum applied voltage waveform are outputted from the main control section to the power output control means as a predetermined control command.

(2) The drive power supply section output voltage is adjusted by the power output control means based on the magnitude information of the applied voltage from the main control section, and the optimum drive power supply section is selected.

(2) A voltage is applied to the laminated piezoelectric element from the selected constant voltage power source based on the magnitude of the applied voltage and application timing information.

(2) The laminated piezoelectric element is displaced in real time in response to the applied voltage, thereby driving the intake valve and the like.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. 1 to 16.

A laminated piezoelectric element 3 as an electric driving means such as a laminated piezoelectric element that is displaced along the moving direction of the intake valve or exhaust valve of the engine and opens and closes the intake valve or exhaust valve, and this laminated piezoelectric element 3 The displacement amplifying mechanism 4 is interposed between the intake valve or the exhaust valve and amplifies the displacement amount of the laminated piezoelectric element 3 by a predetermined factor to operate the intake valve or the exhaust valve. Further, an engine rotation speed measuring means 50 that measures the engine rotation speed, a drive power supply section 51 that drives the laminated piezoelectric element 3, and a power supply output control means 52 that operates based on the output of the engine rotation speed measurement means 50 are provided. A main control section 53 that controls the output level of the drive power supply section 51 via the main control section 53 is provided. The main control section 53 is also provided with a memory 53A that stores a plurality of control map data for controlling the drive power supply section 51. The main control unit 53 has a map data selection function that selects map data for optimal control corresponding to fluctuations in the engine rotation speed measuring means 50, and a power output control means based on the selected control map data. 52 is equipped with an optimal control function that outputs predetermined control commands in real time.

As shown in FIGS. 1, 9, and 10, the laminated piezoelectric element 3 has a structure in which a plurality of piezoelectric elements are stacked to obtain a large displacement. At this time, the thickness of each piezoelectric element and the number of stacked piezoelectric elements are determined by the properties of the piezoelectric element (for example, the amount of dimensional change) and the degree of control accuracy.

FIG. 2 shows a valve operating device for an intake valve that opens and closes an intake port (not shown). This valve operating device opens and closes the intake valve 2 by displacing it in the direction of movement of an intake valve 2 that can reciprocate in the directions of arrows A and B in the figure along a guide member 5 provided on a cylinder head 10. an electric drive means 3; and a displacement amplification mechanism that is interposed between the electric drive means 3 and the intake valve 2 and amplifies the displacement amount of the electric drive means 3 by a predetermined factor and transmits the amplified displacement amount to the intake valve 2. 4.

The intake valve 2 is actually provided at a position where it can open and close an inlet of an intake port (not shown) on the side of a cylinder block (not shown). The intake valve 2 is integrally provided with a plunger 6 on the cylinder head 10 side (upper side in FIG. 1), and in this embodiment, the upper end portion of the plunger 6 forms the main part of the displacement amplification mechanism 4. It constitutes the second piston 7. This plunger 6 and intake valve 2
is one spring retainer 9 that fits into the stopper 8 fixed to the lower part of the second piston 7 from below in the figure.
It is biased in the direction of arrow A in the figure by a valve return spring 12, which is a compression coil spring, interposed between the spring holder 11 and the other spring holder 11 provided on the guide member 5. The state shown in Figure 1 is this valve return spring 1.
2 indicates the state of maximum extension.

The displacement amplification mechanism 4 includes a bottomed cylindrical cylinder 14 in which a first chamber 13 is formed, and a first piston 15 slidably installed in the first chamber 13. It is composed of: A second chamber 16 is formed in the center of the bottom surface of the cylinder 14, and the second chamber 16 is made of a hole having approximately the same diameter as the aforementioned second piston 7. is equipped to be slidable. Here, in Fig. 1, the valve lift is "0" and the second
The piston is shown fully raised. The first chamber 13 inside the cylinder 14 and the second chamber 17 formed on the bottom surface of the cylinder 14 naturally communicate with each other.
3, 17 parts of the first piston 15 and the second piston 7
A fluid storage chamber 18 is formed between the two, and this fluid storage chamber 18 is filled with oil as an incompressible working fluid. Further, the first piston 15 is urged in the direction of arrow A in the figure by a piston return spring 19 made of a leaf spring.

Furthermore, in this embodiment, the fluid storage chamber 18 is provided with a working fluid supply passage 20 that can be communicated with from the outside. The working fluid supply passage 20 includes a first passage section 20A having an L-shaped cross section extending from the first chamber 13 to the second chamber 16 via a part of the cylinder 14, and a second chamber 16 of the first passage section 20A. A second passage portion 20B consisting of a ring-shaped groove formed in a portion of the second piston 7 at a position corresponding to the side, and a portion of the cylinder 14 on the opposite side to the first passage portion 20A via this second passage portion 20B. The third passage portion 20C is formed to correspond to the second passage portion 20B. A check valve 21 is provided at the left end of the third passage portion 20C in the drawing to allow oil to flow only from the outside toward the working fluid supply passage 20 and to prevent oil from flowing in the opposite direction. . An oil passage connected to an oil supply means (not shown) is provided on the left side of the check valve 21 in the drawing.

The electrical drive means 3 is constructed by coaxially stacking a large number of piezoelectric elements 3A that mechanically generate displacement (extend) when a voltage is applied. This electric drive means 3 is housed in an inner case 24 inside an outer case 22 fixed to the upper end opening of the cylinder 14 described above. To explain this in more detail, this outer case 22 has a bottomed cylindrical shape with an open lower end surface in FIG.
3 to the upper end opening of the cylinder 14. Here, a hole 23A having a center on the same straight line as the axis of the plunger 6 described above is formed in the center of the disk member 23, and a hole 23A is formed in the bottom surface of the inner case 24 in a downward direction. A protruding push rod 25 is slidably provided. The inner case 24 is a cylindrical case with a bottom and a flange portion 24A is provided around the upper end opening in FIG. . Further, this inner case 24 has a flange portion 24
It is biased in the direction of arrow A by a rod return spring 26, which is a compression coil spring, interposed between A and the disc member 23. For this reason, the electric drive means 3
Due to the action of the rod return spring 26, the inner case 24 and the outer case 22 are held in place. Further, the first piston 15 described above is brought into pressure contact with the push rod 25 by the action of the piston return spring 19.

An engine control unit (hereinafter referred to as "ECU") 30 is connected to the electric drive means 3, and the ECU 30 controls the energization timing and energization time (ie, the energization time) according to the operating state of the engine. , the opening timing and opening time of the intake valve 2) are controlled. In FIG. 1, reference numerals 41 and 42 indicate oil seals.

In the valve train 1 of this embodiment configured as described above, when the electric drive means 3 is energized by the ECU 30, each piezoelectric element 3A constituting the electric drive means expands in the axial direction. The electric drive means 3 generates a displacement in the direction of arrow B. This displacement causes the inner case 24
The push rod 25 moves in the direction of the arrow B through the push rod 25, and the first piston 15 is urged in the direction of the arrow B by the movement of the push rod 25. This first piston 15 applies pressure to the oil in the fluid storage chamber 18, and this pressure causes the second piston 7 to move in the direction of arrow B. As a result, the intake valve 2 is opened via the plunger 6 provided with the second piston 7. At this time, the displacement of the electric drive means 3 is amplified according to the ratio of the areas of the first piston 15 and the second piston 7 and is transmitted to the intake valve 2. Therefore, for example, even if the amount of displacement of each piezoelectric element 3A constituting the electric drive means 3 is on the order of microns, the amount of movement of the intake valve 2, that is, the amount of valve lift can be on the order of millimeters. FIG. 2 shows the displacement e, f of the electric drive means (piezoelectric element) 30 and the valve lift amount of the intake valve 2 in an engine in which the valve device 1 of this embodiment is applied to the intake valve 2 and the exhaust valve (not shown). c,
The relationship with the valve lift amount d of the exhaust valve is shown. As is clear from this figure, the opening and closing of the intake valve 2 (or exhaust valve) is controlled by the start and stop (on/off) of energization to the electric drive means 3 by the ECU 30, so the timing of opening and closing of the valve is The desired timing can be set according to the software program.

When the ECU 30 stops energizing, each piezoelectric element 3A constituting the electric drive means 3 returns to its original shape. At this time, each return spring 26, 19, 12
The push rod 25, first piston 15, plunger 6, and intake valve 2 return to their original positions (Fig.
state). In this way, the intake valve 2 is
The intake valve 2 is opened and closed by being reciprocated in the B direction.

In this case, when oil leaks from the oil seal 41 during use and the pressure of the oil in the fluid storage chamber 18 decreases, in the state of FIG. 1 where the intake valve 2 is not lifted, the oil supply means (not shown) The oil from
The fluid is replenished via the check valve 21 and the working fluid supply passage 20. (Here, the amount of oil replenished is the small amount of oil that leaked from the oil seal.) On the other hand, even in this case, when the intake valve 2 is lifted (not in its original position), Since the second passage portion 20B is lowered downward in FIG. 1, the replenishment passage 20 is cut off in the middle, and oil does not flow in from the outside even during the opening stroke of the intake valve 2 as well as during the closing stroke. This prevents excessive oil from flowing into the working fluid chamber 18.

Next, the driving power supply section 51 will be explained. This drive power supply unit 51 is composed of first to third constant voltage power supplies 51A, 51B, and 51C. In this embodiment, the output voltages of the first constant voltage power supply 51A, the second constant voltage power supply 51B, and the third constant voltage power supply 51C are added together and applied to the laminated piezoelectric element 3. It has become. That is, for example, the output voltage of the first constant voltage power supply 51A is A [volt], and the output voltage of the second constant voltage power supply 51A is A [volt].
1B output voltage is B [volt], third constant voltage power supply 51
If the output voltage of C is C [volt], then the laminated piezoelectric element 3
When the applied voltage is A [volt], the first constant voltage power supply 51A is applied, when the applied voltage is B [volt], the second constant voltage power supply 51B is applied, and when the applied voltage is C [volt], the second constant voltage power supply 51B is applied. Third
Constant voltage power supplies 51C are independently applied to the laminated piezoelectric element 10. Also, the applied voltage is A + B [volt]
When , the first constant voltage power supply 51A and the second constant voltage power supply 5
1B, when the applied voltage is A + C [volts], the first constant voltage power supply 51A and the third constant voltage power supply 51C are connected, and when the applied voltage is B + C [volts], the second constant voltage power supply 51B and the third constant voltage power supply 51C are connected. constant voltage power supply 51C, and the applied voltage is A+B+C [
Volt], the first constant voltage power source 51A, the second constant voltage power source 51B, and the third constant voltage power source 51C are selected simultaneously. Here, the number of installed constant voltage power supplies is not limited to three.

Furthermore, as shown in FIGS. 9 and 10, it is also possible to apply the output voltages of each constant voltage power source to different parts of the laminated piezoelectric element 3.

Since the laminated piezoelectric element 3 generates a displacement proportional to the applied voltage, as shown in FIGS. 6(a) and (b), in order to generate the displacement of LA, the first constant voltage power source is 51A, the second constant voltage power source 51B may be effectively operated to generate a displacement of LB, and the third constant voltage power source 51C may be effectively operated to generate a displacement of LC.

Furthermore, in order to generate a displacement of LA+LB, the first constant voltage power source 51A and the second constant voltage power source 51B are activated, and in order to generate a displacement of LA+LC, the first constant voltage power source 51A and the third constant voltage power source 51A are activated. Enable constant voltage power supply 51C, LB+L
In order to generate the displacement C, the second constant voltage power supply 52 and the third
In order to enable the constant voltage power supply 51C and generate the displacement of LA+LB+LC, it is sufficient to enable the first constant voltage power supply 51A, the second constant voltage power supply 51B, and the third constant voltage power supply 51C.

Furthermore, even when the output voltages of the respective constant voltage power supplies are applied to different parts of the laminated piezoelectric element 3 as shown in FIGS. 9 and 10, the desired amount of displacement can be obtained in the same manner. .

If the timing of applying this voltage and the magnitude of the applied voltage are changed periodically as shown in FIGS. 6A and 6B or as shown in FIG. Displacement can be applied like a cam lift in a cam mechanism, and the opening/closing timing and opening amount of the intake and exhaust valves can be freely controlled. However, when a voltage is applied to the laminated piezoelectric element 3, the laminated piezoelectric element 3 is suddenly displaced, but as shown in FIG. response is delayed. Therefore, this is also taken into consideration in order to perform fine control.

Various relationship map data include: (1) Relationship map data between engine speed and cam operating angle; (2) Relationship between engine speed and voltage waveform applied to the laminated piezoelectric element 3 to obtain a smooth valve lift. Map data, ■ Relationship map data between engine speed and valve lift amount, ■ Relationship map data between engine speed and intake port pressure, ■ Relationship map data between engine speed and exhaust port pressure, ■ Cycle number and There is map data of intake and exhaust timing strokes, each of which is stored in advance as a database in a memory 53A attached to the main control unit, and can be referenced as needed.

[0033] In this way, the necessary data can be obtained immediately by accessing various related map data from the database without having to calculate each time. This is because the valve must be controlled dynamically, in real time, to ensure stable operation and no jumps or bounces. Moreover, according to the relationship map data of (1) above, (2) to (4) may be relationship map data with the cam operating angle instead of the engine rotation speed.

Although the present invention does not use a cam mechanism,
The term cam operating angle is used because the change in the voltage applied for the expansion and contraction movement of the piezoelectric element can be treated as virtually equivalent to the rotational movement of the cam. Furthermore, the relationship map data is not limited to the above items (1) to (2).

Furthermore, it is assumed here that the cam operating angle is not constant, but variable depending on the purpose.

Next, the operation of this embodiment will be explained with reference to the flowchart of FIG.

■The engine rotation speed is measured by the engine rotation speed measuring means 50 and output to the main control section 53 (FIG. 3).
SP100).

■The main control unit 53 refers to the relationship map data between the engine speed and the cam operating angle stored in the memory 53A, and based on the cam operating angle corresponding to the measured engine speed. The optimum operating time of the valve lift is calculated (SP200 in FIG. 3).

[0039] The main control unit 53 refers to map data stored in the memory 53A regarding the relationship between the engine speed and the voltage waveform applied to the laminated piezoelectric element 3 so as to obtain a smooth valve lift. The optimum applied voltage waveform of the valve lift corresponding to the measured engine speed is calculated (SP300 in FIG. 3).

(2) The main control unit 53 refers to the relationship map data between the engine speed and the valve lift amount stored in the memory 53A, and determines the optimum voltage value corresponding to the valve lift amount. Then, the magnitude of the applied voltage and application time information are output from the main control unit 53 to the power output control means 52 (SP400 in FIG. 3).

■ Based on the magnitude information of the applied voltage from the main control section 53, the power supply output control means 52 controls each constant voltage power supply 51.
The voltages of A, 51B, and 51C are adjusted, and the optimal constant voltage power source is selected (SP500 in FIG. 3).

(2) Based on the magnitude of the applied voltage and the application timing information, a voltage is applied from the selected constant voltage power source to the laminated piezoelectric element 3 (SP600 in FIG. 3).

(2) The laminated piezoelectric element 3 is displaced in accordance with the applied voltage (SP700 in FIG. 3).

■The main control unit 53 determines that the crank angle is 720
It is checked whether it is the same (SP800 in FIG. 3). Then, if the crank angle is 720 degrees, return to ■.

Further, the above-described operation for calculating the optimum operating time of the valve lift (SP200 in FIG. 3) will be explained in detail with reference to the flowchart in FIG. 4.

(2) As shown in FIG. 5, the working angle of the cam is treated as being divided into a valve opening working angle θ1 and a valve closing working angle θ2 (SP201 in FIG. 4).

[0047] The main control unit 53 refers to the map data of the relationship between the engine speed and θ1 and θ2 stored in the memory 53A, and calculates the corresponding θ1 and θ2 based on the measured engine speed ( SP20 in Figure 4
2). Here, as shown in FIG. 11, as the engine speed increases, θ1 and θ2 basically increase.

■The main control unit 53 refers to the relationship map data between engine speed and intake port pressure stored in the memory 30A, and calculates the corresponding intake port pressure based on the measured engine speed. (SP203 in FIG. 4).

(2) The main control unit 53 checks whether the pressure when the valve is opened is positive pressure or negative pressure (SP204 in FIG. 4). If the pressure when the valve is opened is positive, θ1 is increased (SP206 in FIG. 4), and if the pressure when the valve is opened is negative, θ1 is decreased (SP207 in FIG. 4).

(2) The main control unit 53 checks whether the pressure when the valve is closed is positive pressure or negative pressure (SP205 in FIG. 4). If the pressure when the valve is closed is positive, θ2 is increased (SP208 in FIG. 4), and if the pressure when the valve is closed is negative, θ2 is decreased (SP209 in FIG. 4).

■The main control unit 53 refers to the relationship map data between the engine speed and exhaust port pressure stored in the memory 30A, and calculates the intake port pressure based on the measured engine speed. (SP2 in Figure 4
10).

(2) The main control unit 53 checks whether the pressure when the valve is opened is positive pressure or negative pressure (SP211 in FIG. 4). If the pressure when the valve is opened is negative, θ1 is increased (SP213 in FIG. 4), and if the pressure when the valve is opened is positive, θ1 is decreased (SP214 in FIG. 4).

(2) The main control unit 53 checks whether the pressure when the valve is closed is positive pressure or negative pressure (SP212 in FIG. 4). If the pressure when the valve is closed is negative, θ2 is increased (SP215 in FIG. 4), and if the pressure is positive when the valve is closed, θ2 is decreased (SP216 in FIG. 4).

The reason for performing the operations ① to ② will be described below.

As shown in FIG. 11, due to the pulsation of the exhaust operation, the pressure of the pulsation just before the valve closes causes peaks and troughs of torque in the engine. Therefore, when the torque is at a trough, the operating angle θ2 on the close (CLOSE) side is made small to prevent exhaust gas from being sucked back when the intake and exhaust overlap, and when the torque is at a peak, the scavenging by pulsation is actively used. to increase the working angle θ2. Similarly, for the intake operation, the operating angle θ1 on the overlap side
It changes according to the pulsation to prevent blowback and to actively utilize the pulsation (the troughs of the pulsation reduce the operating angle, and the peaks of the pulsation increase the operating angle).

■Engine speed and operating angles θ1 and θ2
Based on the following equations (1) and (2), the respective timing times t1 and t2 shown on the horizontal axis in FIG. 5 are determined (SP217 in FIG. 4).

t1=(duration angle θ1/720)×(120/engine speed) (1)

t2=(working angle θ2/720)×(120/engine speed) (2)

10) θ1
The operating angle of the cam is determined by +θ2 (SP2 in Fig. 4).
18).

11) The valve lift time shown on the horizontal axis in FIG. 6 is calculated from t1+t2 (SP21 in FIG. 4).
9).

12) Exit from this routine.

Furthermore, FIG. 7 shows the operation of calculating the optimal applied voltage waveform for the valve lift (SP300 in FIG. 3) described above.
This will be explained in detail using the flowchart.

(2) The main control unit 53 checks whether there are a plurality of intake valves (SP301 in FIG. 7). If there are no multiple intake valves, proceed to operation (■). If there are multiple intake valves, move to operation ■.

■The main control unit 53 checks whether the engine speed is below a set value (SP302 in FIG. 7).
). If the engine speed is not below the set value, the operation moves to ■. If the engine speed is below the set value, the operation moves to ■.

(2) The main control unit 53 suspends the operation of one of the intake valves (SP303 in FIG. 7).

[0066] When one cylinder has a plurality of intake valves, the reason for stopping the operation of one of the intake valves is to increase the intake air velocity at low speed rotation and to utilize pulsation.

(2) The main control unit 53 checks whether to use a variable cycle (SP304 in FIG. 7). If the setting is not to use a variable cycle, the process moves to operation (■). If it is set to be a variable cycle, move to operation (■).

■The main control unit 53 refers to the map data of the intake and exhaust timing strokes as shown in FIG. 8 stored in the memory 53A, and selects the timing according to the set cycle (see FIG. 7 SP305).

[0069] The main control unit 53 checks whether the spark plug has ignited (SP306 in FIG. 7). If the spark plug ignites, the normal 4-cycle cycle is returned (SP307 in FIG. 7).

(2) The main control unit 53 refers to the map data in the memory 53A and obtains a voltage waveform signal to be applied to the laminated piezoelectric element 3 (SP308 in FIG. 7).

■The main control unit 53 checks whether or not the cylinder is set to be variable (S in FIG. 7).
P309). If it is not set to use variable cylinders, the operation moves to ■. If the cylinder is set to be variable, the main control unit 3 suspends the operation of the intake and exhaust valves of a certain cylinder (SP310 in FIG. 7).

■Exit from this routine.

Although the above embodiment describes a 4-cycle engine, valve lift control corresponding to not only 4-cycles but also 2-cycles, 6-cycles, and 8-cycles is also possible.

[0074] Further finer valve lift control is realized by finer grouping of the laminated piezoelectric elements 3.

[0075] Also, instead of the laminated piezoelectric element, a magnetostrictive element,
In particular, it is also possible to use a giant magnetostrictive element whose dimensional change and torque are larger than those of the piezoelectric element.

[0076]

As the present invention is constructed and functions as described above, it is possible to perform complex valve timing control in real time. Therefore, ■The cam operating angle can be changed according to the speed.■By changing the working angle according to the pulsation of the intake and exhaust system, the drop in the torque valley can be minimized and the torque peak can be maximized. ■By stopping one valve of multiple valves and inhaling with the other valve, the air intake speed can be increased and combustion efficiency can be improved.■4
It is possible to provide an unprecedented and superior engine valve drive control device that is capable of valve timing control corresponding to not only 2-cycle, 6-cycle, and 8-cycle cycles.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing one embodiment of the present invention.

FIG. 2 is a sectional view showing a valve train portion equipped with a laminated piezoelectric element portion in FIG. 1;

FIG. 3 is an explanatory diagram showing the basic operation of FIG. 2;

FIG. 4 is a flowchart showing an example of the operation in FIG. 1;

FIG. 5 is a detailed flowchart for explaining the operation of calculating the optimum valve lift operation time in FIG. 4;

6 and 7 are relationship diagrams between valve lift amount and time.

8 and 9 are examples of the relationship between piezoelectric element switching and piston displacement.

FIG. 10 is a detailed flowchart for explaining the operation of calculating the optimum applied voltage waveform for the valve lift in FIG. 4;

FIG. 11 is map data of intake and exhaust timing strokes.

FIGS. 12 and 13 are examples of the distributed application of voltage to the laminated piezoelectric element.

FIG. 14 is a block diagram showing a second embodiment of the present invention.

FIG. 15 is an explanatory diagram showing how the operating angle is changed due to pulsation during exhaust.

FIG. 16 is an explanatory diagram showing a rest state of the intake valves in a four-valve engine.

FIG. 17 is an explanatory diagram showing the relationship between the displacement of the piezoelectric element and the shape of the valve lift.

FIG. 18 is an explanatory diagram showing conventional variable valve timing.

[Explanation of symbols]

3 Electrical driving means such as laminated piezoelectric element 4
Displacement amplification mechanism 50 Engine rotation speed measuring means 51 Drive power supply unit 51A First constant voltage power supply 51B Second constant voltage power supply 51C Third constant voltage power supply 52 Power output control means 53 Main control unit 53A Memory

Claims (1)

[Claims] 1. Electric driving means such as a laminated piezoelectric element that is displaced along the moving direction of an intake valve or exhaust valve of an engine to open and close the intake valve or exhaust valve, the electric driving means and the intake valve. or a displacement amplifier interposed between the exhaust valve and the displacement amplifier that amplifies the displacement amount of the electric drive means by a predetermined factor to operate the intake valve or the exhaust valve, and measures the rotational speed of the engine. a rotational speed measuring means, a driving power supply section that drives the electric drive means, and a power supply output control means that operates based on the output of the engine rotational speed measuring means and controls the output level of the driving power supply section. The main control section is provided with a memory storing a plurality of control map data for controlling the driving power source section, and the main control section is equipped with a memory that stores a plurality of control map data for controlling the drive power source section. A map data selection function that selects map data for optimal control according to fluctuations in
A valve drive control device for an engine, comprising an optimum control function for outputting a predetermined control command to the power output control means in real time based on the selected control map data.