JPH03189312A - Electromagnetic force valve driver - Google Patents

Abstract

PURPOSE:To enable it to stabilize driving force, acting on both intake and exhaust valves without receiving any effect due to movements of these valves by setting up both magnetic poles of a superconductive electromagnet in opposition to a plate part of a driver interlocking with these intake and exhaust valves. CONSTITUTION:A driver 12 consisting of an electric conductor is connected to the shaft end of an intake valve 1. Then, an electromagnet consisting of both magnetic poles being opposed to both sides of a plate of this driver 12 and a superconductive coil 15 is set up in an upper part of the intake valve 1. In addition, there is provided with a brush 13 in opposition to both sides in a view A direction of the driver 12. When those of superconductive coil 15 and brush 13 are energized from a control unit 2, powerful magnetic flux works on the driver 12 from a superconductive electromagnet at all times. An electric current generated in the driver 12 after being energized via this brush 13 receives the driving force from a magnetic field. With this constitution, the driving force acting on the intake valve 1 comes to such that is stabilized without receiving any effect of movement of the intake valve 1.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an electromagnetic force valve drive device that controls opening and closing of intake and exhaust valves of an engine using a force acting on a current in a magnetic flux generated by a superconducting electromagnet.

(Prior art) As a conventional opening/closing drive device for intake and exhaust valves, a camshaft with intake and exhaust cams arranged on a single shaft is installed on the top or side of the engine, and the rotation is transmitted by a belt, etc. The means connects the crankshaft, which is the rotating shaft of the engine, and the camshaft, and drives the camshaft to rotate in synchronization with the rotational phase of the engine. Then, by pushing the shaft end surface of the valve from the cam surface of the camshaft through a link mechanism such as a rocker arm or bushing rod, there is a device that opens and closes the intake and exhaust valves that are always biased in the closing direction by a spring. .

In addition, as another device, an intake camshaft with an intake cam and an exhaust camshaft with an exhaust cam are installed at the top of the engine, and the cam surface of the intake camshaft is connected to the shaft end of the intake valve. Then, the intake and exhaust valves are opened by directly pushing the shaft end surface of the exhaust valve with the cam surface of the exhaust camshaft.

(Problems to be Solved by the Invention) Such a conventional intake/exhaust valve opening/closing drive device requires a camshaft and a link mechanism to be attached to the engine, which increases the size of the engine. Furthermore, since the camshaft and link mechanism are driven by the output shaft of the engine, a portion of the engine output is consumed due to frictional resistance when driving the camshaft and link mechanism, reducing the effective output of the engine. Also, while the engine is running, the intake and exhaust gas (
The valve opening/closing timing cannot be changed, and the valve opening/closing timing is adjusted according to the specified engine speed.
When operating at a rotation speed different from the predetermined rotation speed, the output and efficiency of the engine decrease.

In order to solve the above problem, a device for opening and closing intake and exhaust valves using electromagnetic force generated by an electromagnet instead of using a camshaft is described in Japanese Patent Laid-Open No. 58-183805 or Japanese Patent Laid-Open No. 61-76713. ing. However, the configuration of the electromagnet in the device disclosed in the above two publications is such that a magnetic body attached to an intake/exhaust valve is attracted by an electromagnet disposed in the moving direction of the intake/exhaust valve, and the intake/exhaust valve is driven by the attraction force. It is something to do. Therefore, as the intake/exhaust valve moves, the distance between the electromagnet and the magnetic body changes, so the attractive force acting on the magnetic body also changes, causing a problem in that the driving of the intake/exhaust valve becomes unstable.

The present invention has been made in view of the above points, and it is an object of the present invention to provide an electromagnetic force valve drive device in which the driving force acting on the intake and exhaust valves is not affected by movement of the intake and exhaust valves and is stable.

(Means for Solving the Problems) According to the present invention, there is provided a driving body that is connected to an intake and exhaust valve of an engine and is made of a conductive material and can freely reciprocate, a superconducting electromagnet that generates a magnetic flux, an energizing means that energizes the driving body in a direction perpendicular to the reciprocating direction and the passing direction of the magnetic flux, and energization control means that controls the amount and direction of energization of the energizing means. It is possible to provide an electromagnetic force valve driving device characterized by having the following.

(Function) In the electromagnetic force valve driving device of the present invention, a strong magnetic flux generated by a superconducting electromagnet is constantly applied to a conductor interlocking with an intake/exhaust valve, and the current generated by energizing the conductor is removed from the magnetic field. Since the intake and exhaust valves are driven by the received force, the driving force acting on the intake and exhaust valves is not affected by the movement of the intake and exhaust valves and is stable.

(Example) Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block diagram showing a drive device according to the invention.

Among the intake and exhaust valves, the intake valves will mainly be described below.

1 is an intake valve made of a lightweight, high-strength material such as ceramics. The shaft portion of the intake valve 1 is a valve guide 11.
It is freely supported in the axial direction by a shaft, and a driving body 12 made of a conductive material is connected to the shaft end. A perspective view of the driver 12 is shown in the upper right corner of the figure. As shown in the figure, the driving body 1
2 has a flat plate portion, and the arrow view from A is shown on the left side of the broken line, and the arrow view from B is shown on the right side. Above the intake valve 1 are magnetic poles 1 facing on both sides of the flat plate portion of the driver 12.
An electromagnet consisting of a superconducting coil 15 and a superconducting coil 15 is provided. The superconducting coil 15 is made of a superconducting material and is cooled with liquid helium, and the liquid helium is further cooled with liquid hydrogen. Hydrogen gas generated by vaporizing the liquid hydrogen is used as fuel for the engine 3.

Further, a brush 13 is provided in a direction perpendicular to the direction facing the magnetic pole 14.
are connected facing each other. Note that a spring 16 is disposed between the driver 12 and the valve guide 11, and acts on the intake valve 1 with a bias force in the normally closing direction.

The superconducting coil 15 and brush 13 are connected to an input/output interface 24 of the control unit 2. Inside the control unit 2, in addition to the human output interface 24 for inputting and outputting signals with the outside,
A ROM 22 that stores programs and data in advance, a CPU 21 that performs calculations based on the programs stored in the ROM 22, and an R that temporarily stores input signals and calculation results.
AM23 and a control memory 25 that controls the flow of signals within the control unit 2 are provided.

A rotation sensor 31 that detects the rotation speed and crank angle of the engine 3 is disposed near the rotation axis of the engine 3. The rotation sensor 31 is connected to the input/output interface 24, and is connected to the rotation speed signal and the crank angle. A crank angle signal is input to the control unit 2.

Next, the operation of the present invention will be explained.

FIG. 2 is a diagram showing the I-1 cross section in the N1 diagram.

The superconducting coil 15 is energized, and the magnetic pole 14 on the left side in the figure
is the north pole, and the right magnetic pole 14 is the south pole, and the magnetic flux is passed through the drive body 12 from right to left. And brush 13
The driving body 12 is energized from above to below. Then, according to Fleming's left-hand rule, a driving force acts on the driving body 12 in an upward direction perpendicular to the plane of the drawing. Since the acting direction of the driving force is the opening direction of the intake valve 1, the intake valve 1 is driven in the opening direction.

Next, the relationship between the amount and direction of energization and the amount of movement of the intake valve 1 will be explained.

FIG. 3 is a diagram showing the relationship between the amount of energization, the direction of energization, and the amount of movement of the intake valve 1. The upper part of FIG. 0 is a profile curve, and the lower part is a diagram showing the energization state. Note that the energization direction is defined as the positive direction that drives the intake valve 1 in the opening direction, and the reverse direction as the energization direction that drives the intake valve 1 in the closing direction.

Until the opening timing of the intake valve 1 is reached, the current is applied in the opposite direction to maintain the intake valve 1 in the closed state.
The intake valve 1 is driven in the opening direction. When the intake valve 1 moves a predetermined distance, the energization direction is reversed and the speed of movement in the opening direction is reduced. Then, after stopping the intake valve 1, it is moved 8 times in the closing direction. If the intake valve 1 is seated in this state, the impact will be large and there is a risk that the intake valve 1 will be destroyed, so the direction of energization should be reversed again to the positive direction and the intake valve 1
The movement speed in the closing direction is reduced to reduce the seating impact. After seating, the current direction is reversed again to keep the intake valve 1 closed until the magnetic field opens.

Next, a control circuit for the superconducting coil 15 will be explained.

FIG. 4 is a diagram showing a control circuit for the superconducting coil 15.

The power source 61 is connected to a parallel circuit of a fixed resistor 63, a superconducting coil 15, and a variable resistor 65 via a switch 62. The intermediate portion of the superconducting coil 15 and the intermediate terminal of the variable resistor 65 are connected via a voltage detector 64.
The superconducting coil 15 and the variable resistor 65 form a whitstone bridge. Further, the output terminal of the voltage detector 64 is connected to an alarm signal generator 66.

If a normal conducting part occurs in a part of the superconducting coil 15, the normal conducting part will rapidly expand to the entire coil, and there is a danger that the coil will be destroyed. Each half of the superconducting coil 15 and the variable resistor 65 (a Whetstone bridge is formed), so when a normal conduction portion occurs in a part of the superconducting coil 15, the voltage detector 64 detects the occurrence of the normal conduction as a voltage. is detected and outputs a signal to the alarm signal generator 66. The alarm signal generator 66 outputs an alarm signal based on the signal from the voltage detector 64, turns off the switch 62, and turns off the signal to the superconducting coil 15. Then, the electrical energy held in the superconducting coil 15 is consumed by the resistor 63, and the superconducting coil 15 is protected and will not be destroyed.

By the way, when engine 3 finishes operating, superconducting coil 1
The electric power supply to the intake valve 1 disappears, and the electromagnetic force that holds the intake valve 1 in the closed state disappears, so the spring 16 holds the intake valve 1 in the closed state. The holding force of the spring 16 is set to be sufficiently small relative to the driving force in the opening direction.

A relationship map between the engine speed and the inter-valve timing is stored in advance in the ROM 22, and by changing the inter-valve timing as the engine speed changes, the engine 3 The output and efficiency of the system can be improved. Also engine 3
It is also possible to control the cylinders by increasing or decreasing the number of operating cylinders by driving or stopping the intake and exhaust valves for each cylinder as the rotational speed increases or decreases.

The operation of one intake valve 1 has been explained above, but
It is also possible to drive multiple intake valves with one electromagnet.

FIG. 5 is a diagram showing an embodiment in which a plurality of intake valves are driven by one electromagnet.

By arranging the driving bodies 12 connected to a plurality of intake valves 1 alternately with the magnetic passages 4, the magnetic flux acting between the magnetic poles 14 passes through each driving body 12 without attenuation. By individually controlling the energization state of the driving body 12, each intake valve 1 can be driven and controlled.

Although the embodiments of the present invention have been described above mainly regarding intake valves, it is clear that the drive device according to the present invention can be applied to exhaust valves as well. Further, since various different embodiments can be easily constructed without departing from the spirit of the invention, the present invention is not limited to specific embodiments other than the limitations set forth in the claims.

(Effects of the Invention) As explained above, a strong magnetic flux generated by a superconducting electromagnet is constantly applied to a conductor that is interlocked with an intake/exhaust valve, and the current generated by energizing the conductor receives the force from the magnetic field. Therefore, it is possible to provide an electromagnetic force valve driving device in which the driving force acting on the intake and exhaust valves is not affected by movement of the intake and exhaust valves and is stable.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing an embodiment of the present invention, Fig. 2 is a diagram showing the I-1 cross section in Fig. 1, and Fig. 3 shows the amount and direction of energization and the amount of movement of the intake valve. Figure 4 is a diagram showing the relationship between
The figure shows an example in which a plurality of intake valves are driven by one electromagnet. 1... Intake valve, 2... Control unit,
12...Driver, 15...Superconducting coil.

Claims (3)

[Claims] (1) A driving body that is connected to the intake and exhaust valves of the engine and is made of an electrical conductor and can freely reciprocate; a superconducting electromagnet that generates a magnetic flux that passes perpendicularly to the direction of the reciprocating movement of the driving body; An electromagnetic force valve driving device comprising: energizing means for energizing in a direction perpendicular to the direction of reciprocating motion and the passing direction of magnetic flux; and energizing control means for controlling the amount and direction of energization of the energizing means. . (2) A plurality of the above-mentioned driving bodies are arranged in parallel in the direction in which the magnetic flux passes,
2. The electromagnetic force valve drive device according to claim 1, wherein the energization control means individually controls the amount and direction of energization for each of the plurality of drive bodies. (3) The electromagnet according to claim (1) or (2), characterized in that the superconducting electromagnet is cooled by at least liquid hydrogen, and hydrogen gas generated by vaporizing the liquid hydrogen is used as fuel for the engine. Power valve drive.