JPH0381511A - Induced type electromagnetic valve driving device - Google Patents

Abstract

PURPOSE:To have a strong driving force at the time of start-up of driving without influence by movement of an intake and exhaust valve, by forming proceeding magnetic field with a magnetic pole provided aside on the side surface of a secondary electric conductor provided around a needle. CONSTITUTION:In a controller 4, at the normal time when an engine is operated, an acceleration pedal stepping amount of an accelerator pedal is detected from a load sensor 6, and an engine speed is detected from a rotation sensor 5. Then, the opening and closing timing of an intake valve 1 corresponding to the acceleration pedal stepping-in amount and the engine speed is calculated with a relation map which is set beforehand. When a crank angle detected by the rotating sensor 5 has the opening timing of the intake valve 1, the intake valve 1 is primarily driven by induced current generated on a secondary electric conductor 22 by electrifying an upper part coil 34, and a magnetic field formed by an exciting coil 33. After driving is started, an alternating electric power is supplied to the exciting coil 33, and a magnetic field formed by magnetic flux from a magnetic pole 32 makes a proceeding magnetic field. It is thus possible to opening-and-closing drive the intake valve 1.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an induction type electromagnetic force valve driving device that opens and closes intake and exhaust valves of an engine using electromagnetic force.

(Prior Art) A conventional intake/exhaust valve opening/closing drive device uses a camshaft that rotates in synchronization with the engine rotational phase to push the end face of the valve shaft through a link mechanism such as a rocker arm or bushing rod. It opens and closes the intake and exhaust valves, which are always biased in the closing direction by springs. The opening/closing drive device requires a camshaft and a link mechanism to be installed in the engine, which increases the size of the engine and consumes a portion of the engine output due to frictional resistance when driving the camshaft and link mechanism. , the effective output of the engine decreases.Furthermore, since the opening/closing timing of the intake and exhaust valves cannot be changed while the engine is running, the valve opening/closing timing must be adjusted in accordance with a predetermined engine speed. When operating at a rotation speed different from the rotation speed, the output and efficiency of the engine decrease.

Therefore, in order to solve the above problem, a device is proposed in which the intake and exhaust valves are driven to open and close by electromagnetic force using an electromagnet instead of using a camshaft, which is described in Japanese Patent Laid-Open No. 58183805 or Japanese Patent Laid-Open No. 6176713. .

(Problems to be Solved by the Invention) However, the devices disclosed in the above two publications
) A magnetic body attached to the air valve is attracted by an electromagnet disposed in the direction of movement of the intake/exhaust valve, and the intake/exhaust valve is driven by the attraction force.

Since the attraction force acting on the magnetic body is inversely proportional to the square of the distance between the electromagnet and the 1iit magnetic body, the attraction force changes as the distance changes, causing the problem that the drive of the suction valve becomes unstable. There is. Furthermore, a strong accelerating force must be applied to the intake and exhaust valves at the start of driving, but in the devices disclosed in the above two publications, the distance between the electromagnet and the magnetic body is maximum at the start of driving, so The driving force acting on the exhaust valve is minimal.

The present invention has been made in view of the above points, and is capable of stably controlling the opening and closing of the intake and exhaust valves without being affected by the driving force acting on the intake and exhaust valves or by movement of the intake and exhaust valves, and by starting the drive. The present invention attempts to provide an electromagnetic force valve driving device that sometimes applies a strong driving force to intake and exhaust valves.

(Means for Solving the Problem) According to the invention, a cylindrical movable magnetic pole that is connected to an intake and exhaust valve of an engine and can freely reciprocate, and a cylindrical movable magnetic pole that faces the outer peripheral surface of the movable magnetic pole and are arranged in parallel in the axial direction of the cylinder. A magnetic pole, which is wound around the magnetic pole and forms a magnetic field in the same direction during initial operation of the intake and exhaust valves,
The magnet has a coil that forms a traveling magnetic field in the cylindrical axis direction when in an open state, a secondary conductor that faces the magnetic pole and covers the outer peripheral surface of the movable magnetic pole, and a fixed magnetic pole that is pushed into the secondary conductor. It is characterized by comprising an electromagnet that induces a current in the circumferential direction in the secondary conductor when the exhaust valve is initially driven, and an energization control means that controls the energization state of the coil and the electromagnet to open and close the intake and exhaust valves. We provide a guided electromagnetic valve cantering device.

(Function) In the induction type electromagnetic Kahalb drive device of the present invention, a traveling magnetic field is formed by the magnetic poles arranged in parallel on the side surface of the secondary conductor surrounding the movable element, and the current induced in the secondary conductor is Since the intake and exhaust valves are reciprocated by the electromagnetic force received from the advancing magnetic field, the driving force does not change even if the position of the intake and exhaust valves changes, and therefore stable opening/closing control can be performed. In addition, during initial driving, a magnetic field in the same direction is applied to the secondary conductor, and the current induced by the magnetic poles arranged inside the secondary conductor is driven by the electromagnetic force received from the magnetic field in the same direction. The driving force acts on the entire circumference of the secondary conductor, and therefore a strong driving force can be generated.

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

FIG. 1 is a block diagram showing the configuration of a drive device according to the invention. Although the engine is provided with an intake valve and an exhaust valve as described above, the drive device according to the present invention can be applied to both the intake and exhaust valves, so the following explanation will mainly be made regarding the intake valve.

Reference numeral 1 denotes an intake valve made of a ceramic material such as silicon nitride or a heat-resistant alloy, which is lightweight and has excellent high-temperature strength.

The shaft portion of the intake valve 1 is rotatably supported by a valve kite 12. When the intake valve 1 is closed, the umbrella portion of the intake/exhaust valve 1 is seated on the valve seat 13 to close the intake port, as shown in this figure.

A movable element 2 is connected to the shaft end of the intake valve 1 .

The mover 2 includes a cylindrical magnetic passage 21 and a magnetic passage 2.
It is composed of a secondary conductor 22 that covers the outer peripheral surface of 1,
The inner circumferential surface of the secondary conductor 22 and the outer circumferential surface of the magnetic path 21 are screwed together by screws formed in each. The magnetic path 21 is made of a magnetic material in order to increase the magnetic flux density, and is formed by arranging amorphous thin plates of magnetic metal in a cylindrical shape, for example. The movable element 2 is a rotor stopper 2 made of hard plastic.
3 to the shaft end of the intake valve 1.

A driving section 3 is arranged around the movable element 2. The drive unit 3 includes a central magnetic pole 3 pushed inside the magnetic path 21.
1, a plurality of magnetic poles 32 facing the secondary conductor 22 and disposed around the outer peripheral surface of the movable element 2, an excitation coil 33 wound around each of the magnetic poles 32, and an excitation coil 33 wound around the central magnetic pole 31. The upper coil 34, etc.

The excitation coil 33 and the upper coil 34 are connected to the controller 4 and receive power from the controller 4.

Detection signals are input to the controller 4 from a rotation sensor 5 that detects the rotational speed and crank angle of the engine, and a load sensor 6 that detects the amount of depression of an accelerator pedal (not shown).

The controller 4 includes a human output interface that controls the input of the detection signal and the supply of power, a ROM that stores programs and various relationship maps in advance, a CPU that executes calculations in accordance with the programs stored in the ROM, and a calculation result. The controller 4 is composed of a RAM for temporarily storing data, a control memory for controlling the flow of signals inside the controller 4, and the like.

Next, the operation of the apparatus of the present invention having the above configuration will be explained.

While the engine is running, the load sensor 6 constantly detects the amount of accelerator pedal depression and the rotation sensor 5 detects the engine rotation speed, and a preset relationship map is used to detect the intake air that corresponds to the amount of depression and rotation speed. Calculate the opening/closing timing of valve 1. Then, when the crank angle detected by the rotation sensor 5 becomes tied between the intake valves 1,
By energizing the upper coil 34, an induced current is generated in the secondary conductor 22, and the intake valve 1 is initially driven by the induced current and the magnetic field formed by the excitation coil 33.

After the drive is started, alternating power is supplied to the excitation coil 33, and the magnetic field formed by the magnetic flux from the magnetic pole 32 is used as a traveling magnetic field, thereby driving the intake valve 1 to open and close.

FIG. 2(I) is a diagram showing the state during initial driving, and FIG. 2(II) is a diagram showing the state after initial driving.

Note that in this figure, diagonal lines indicating a cross section are omitted for clarity of explanation.

When the intake valve 1 is in the closed state, the upper coil 34 is energized to apply a downward magnetic flux to the central magnetic pole 31.

When the crank angle reaches the timing between the intake valve 1 and the intake valve 1, as shown in FIG.
Change to Then, an induced current is generated in the secondary conductor 22 due to mutual induction. The direction of the induced current is the direction that cancels the magnetic flux a, that is, when viewed from above in the figure, a clockwise induced current is generated. By the way, the direction of energization to the upper coil 34 is reversed, and at the same time, the excitation coil 33 is energized to cause a magnetic flux to act on the secondary conductor 22 from the outer periphery inward. Then, the current induced in the secondary conductor is subjected to an electromagnetic force shown by the left-hand rule of the magnetic flux, that is, a downward electromagnetic force in the case of this figure. Since the electromagnetic force acts on the entire circumference of the secondary conductor, it acts on the intake valve 1 as a strong driving force, driving the intake valve 1 in the opening direction.

The driving force during the initial drive disappears when the energization state of the upper coil 34 shifts to a steady state. Therefore, Figure 2 (II
), the energization state of the wJ magnetic cocoil 33 is switched to alternating power, and a downward traveling magnetic field in this figure is applied to the secondary conductor 22.

Next, a case will be described in which the polarity of the magnetic pole 32 changes from the state shown in C to the state shown in d as the traveling magnetic field advances.

In the state shown in C, a magnetic flux e is acting on the secondary conductor 22. When the polarity of the magnetic pole 32, where the magnetic field does not advance, shifts to the state shown in d, the magnetic flux e decreases, so that the secondary conductor 22
An induced current is generated in the direction of maintaining each magnetic flux e, that is, in the direction shown in the figure. However, at the time when the induced current is generated, the polarity of the 0 magnetic pole 32 has already shifted to the state shown in d. Then, the current induced in the secondary conductor 22 receives a downward electromagnetic force due to the magnetic flux from the polarity shown in d. Therefore, the intake valve 1 is driven downward. Therefore, the movable element 2 is driven in the same direction as the magnetic field advances.

Therefore, in order to drive the intake valve 1 in the closing direction, the alternating direction of the alternating power supplied to the excitation coil 33 may be reversed to form an upward traveling magnetic field. When the intake valve 1 is seated, a driving force in the opening direction is applied to the intake valve 1 in the same manner as in the initial drive described above, the speed in the closing direction is reduced, and the intake valve 1 is seated gently.

By the way, the magnetic path 21 and the central magnetic pole 31 serve as paths for the magnetic fluxes I and E, and are used to reduce the magnetic resistance when the magnetic fluxes flow and to increase the driving force. Also,
As mentioned above, since the outer circumferential surface of the magnetic passage 21 is threaded, the magnetic flux flowing from the magnetic pole 32 to the magnetic passage 21 is not biased in one part compared to a case where the outer circumferential surface is flat. 1. In addition, since the distance between the magnetic pole 32 and the magnetic path 21 is reduced, the amount of magnetic flux can be increased.

The bias of the spring 24 that holds the intake valve 1 in a closed state is set to be sufficiently small with respect to the electromagnetic force described above.

Although the embodiments have been described in detail above, various different embodiments can be easily constructed without departing from the spirit of the present invention. There is no limit to the examples.

(Effects of the Invention) As explained above, according to the present invention, a traveling magnetic field is formed by the magnetic poles arranged in parallel on the side surface of the secondary conductor surrounding the mover, and a current is induced in the secondary conductor. Since the intake and exhaust valves are reciprocated by the electromagnetic force received from the traveling magnetic field, the ffi power does not change even if the position of the intake and exhaust valves changes, and therefore stable opening/closing control can be performed. Also, during initial drive, a magnetic field in the same direction is applied to the secondary conductor, and the current induced by the magnetic poles arranged inside the secondary conductor is driven by the electromagnetic force received from the magnetic field in the same direction. So,
The present invention provides an induction type electromagnetic force valve driving device in which a driving force acts on all secondary conductors, thereby generating a strong driving force.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 (I) is a diagram showing the initial driving state, and FIG. 2 (I+
) is a diagram showing the state after initial driving. DESCRIPTION OF SYMBOLS 1... Intake valve, 2... Mover, 3... Drive unit, 4... Controller, 5... Rotation sensor, 6...
- Load sensor, 22... Secondary conductor, 31... Central magnetic pole, 32... Magnetic pole, 33... Exciting coil, 34...
- Upper coil.

Claims (2)

[Claims] (1) A cylindrical movable magnetic pole that is connected to the intake and exhaust valves of the engine and can freely reciprocate, magnetic poles that face the outer peripheral surface of the movable magnetic pole and are arranged in parallel in the axial direction of the cylinder, and intake and exhaust valves that are wound around the magnetic poles. a coil that forms a magnetic field in the same direction during initial drive and a traveling magnetic field in the cylindrical axis direction when in the open state; a secondary conductor that faces the magnetic pole and covers the outer peripheral surface of the movable magnetic pole; An electromagnet that has a fixed magnetic pole inserted inside the conductor and induces a circumferential current in the secondary conductor when the intake and exhaust valves are initially driven, and an electromagnet that controls the energization state of the coil and electromagnet to open and close the intake and exhaust valves. 1. An induction type electromagnetic force valve driving device, characterized in that it has an energization control means for controlling the current flow. (2) The induction type electromagnetic force valve driving device according to claim (1), wherein the movable magnetic pole and the secondary conductor are screwed together.