JPH05248213A - Valve driving device for engine and its manufacture - Google Patents

Abstract

PURPOSE:To obtain a lightweight valve driving device which can generate large driving force. CONSTITUTION:An oscillating body 4 which is prepared by laminating fine plate-like electric conducting wires 6 in a cylindrically formed ceramic is connected to a valve 1. A fixed magnetic pole 7' is further provided for generating a flux which crosses the electric conducting wires 6 in a chain form. Since a plurality of conductors are laminated in the ceramic, a large ampere-turn can be obtained. The oscillating body 4, being made of material other than iron has, a little weight. Thus, a large driving force is generated. Ceramic green sheets and thin metal plates prepared by punching the electric conducting wires 6 are laminated and bent in a circular arc. The bent partially produced item is baked thereby forming the oscillating body 4. The oscillating body 4 is thus easily manufactured.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a valve drive device for an engine and a method for manufacturing the same, in which the followability of valve opening / closing is improved according to the load condition of the engine.

[0002]

2. Description of the Related Art An ordinary mechanical valve opening / closing apparatus for an engine is driven by an output shaft of the engine and rotates in synchronization with an engine rotation phase. The cam surface of the cam shaft is a shaft of the valve via a rocker arm or a push rod. By pushing the end face, the intake and exhaust valves that are always biased in the closing direction by the spring are opened.

In the above-mentioned valve opening / closing device, a mechanical structure such as a cam shaft and a rocker arm must be attached to the engine, so that the size of the engine becomes large. Further, a part of engine output is consumed due to frictional resistance when driving a mechanism such as a cam, and the effective output of the engine is reduced. Furthermore, in the valve opening / closing device using the cam mechanism described above, the opening / closing timing of the intake and exhaust valves cannot be easily changed during the operation of the engine.

In order to solve the above problem, therefore, the intake and exhaust valves are not opened and closed by a camshaft, but the movable magnetic poles connected to the intake and exhaust valves are attracted by the magnetic force of an electromagnet fixed to the engine side. A valve drive device has been developed which repulsively opens and closes the intake and exhaust valves so that the opening and closing timing can be changed. For example, it is described in Japanese Patent Application No. 63-334959 (Japanese Patent Application Laid-Open No. 2-181007). .

[0005]

In the conventional valve drive system as described above, particularly the valve drive system for driving the exhaust valve requires an extremely large actuating force at the initial stage of valve opening. To increase the driving force, the magnetic force of the permanent magnet must be increased or the ampere turn of the movable magnetic pole must be increased. However, since the location where the valve drive device is arranged is small, it is not possible to arrange a large magnet having a strong magnetic force, and it is also impossible to wind many conductive wires of the coil of the movable magnetic pole. Furthermore, in order to smoothly drive the valve with a small force, it is necessary to reduce the weight of the movable magnetic pole as much as possible, but it is very difficult to realize this.

Therefore, the present invention is intended to provide an engine valve drive device that is lightweight and capable of generating a large drive force, and a method of manufacturing the same.

[0007]

In order to solve the above-mentioned problems, the present invention provides an oscillator for driving a valve of an engine, in which a thin plate-shaped electric conductor wire is laminated in a cylindrical ceramic. A valve drive device for an engine, comprising a fixed magnetic pole for generating a magnetic flux interlinking with an electric conductor wire of the oscillator while being connected to the valve. A valve drive for an engine, which has a manufacturing process in which a laminate of a thin metal plate formed by punching a conductor wire is curved into an arc shape, and the curved semi-finished product is fired to form an oscillator. A method for manufacturing a device is provided.

[0008]

A plurality of laminated conductors are provided in a cylindrical ceramic to obtain a large ampere-turn, and the oscillator is light because it does not use an iron core. Therefore, a large driving force is generated.

[0009]

An embodiment of the present invention will be described in detail below with reference to the drawings. In FIG. 1, a cylindrical rocking body 4 is attached to an upper end of a valve shaft 2 of a valve 1 via a cotter 3. A plurality of electric conductor wires 6 are laminated inside the oscillator 4, the structure and manufacturing method of which will be described later. On the outer periphery of the oscillator 4, a plurality of fixed magnetic poles 7'are provided in the longitudinal direction of the oscillator 4 across a narrow gap so as to face each other as shown in FIG. Independent fixed coils 8 are wound around these fixed magnetic poles 7 '. The roots of these fixed magnetic poles 7'are attached to the yoke 7 surrounding these outer peripheries. A relay magnetic path 9 made of a columnar soft magnetic material is provided in the cylinder of the rocking body 4 with a certain gap.
The top of the relay magnetic path 9 is attached to the yoke 7 via a supporter 9'made of a magnetic material. 10 is a valve seat. Reference numeral 11 denotes a bush for movably guiding the valve shaft 2 through the cylinder head 12. In addition,
Although not shown, the valve 1 is normally biased in the closing direction by a weak spring.

As shown in FIG. 3, the oscillating body 4 is formed in a cylindrical shape, and contact members 20 and 21 are provided at symmetrical positions with respect to a center line C thereof, and adjacent to the contact members 20 and 21. Two cores 22 each having a moving coil inside,
23 are provided.

Next, a method of manufacturing the cores 22 and 23 and a method of assembling the oscillator 4 will be described. As shown in FIG. 4, a thin copper plate is punched out and has a coil conductor 24 on an upper portion and a lower end with an inner contact terminal 25 and an outer contact terminal 26, and a ceramic powder binder. It is similar to the green sheet 28 and the first coil plate 27, which are formed into a film by rolling the mixture kneaded in
It is formed by punching out a thin copper plate and has a coil conductor 29 on the upper part and a second coil plate 31 having two inscribed terminals 30 and 30 on the lower end.
A plurality of second coil plates 31 are alternately stacked, and finally the first coil plates 27 are turned upside down and stacked, and a pressure is applied from the upper and lower surfaces of these laminated bodies to form a plate as shown in FIG. The shape 32 is formed. Next, in the second pressurizing step, the plate-like body 32 is curved and processed into a shape as shown in FIG. Then, in this state, the plate-shaped body 32 is fired, the green sheet is made into a ceramic, and the plate-shaped body 32 is integrated. Two such integrated plate-like bodies 32 are opposed to each other, and the contact material 21 is sandwiched between them as shown in FIG. 6, and these are adhered and integrated by an appropriate method. After that, a groove is dug between the inscribed terminals 25 and 30 or between the inscribed terminals 30 and 30 by the laser cutting method to make the inscribed terminal 1
Move them one by one and connect by embedding metal. Then, the external terminals 26, 26 and the contact materials 20, 21 are connected respectively. With this configuration, currents in the same direction can flow in each coil conductor 24.

An aluminum oxide (Al2 O3) disc having a cotter mounting hole in the center is adhered to the lower surface of the cylindrical intermediate product thus formed, and then known calcination and main calcination are performed. The oscillator 4 having an integral structure is created.

As shown in FIGS. 3 and 6, the brushes 14 held by the brush holder 13 are slidably brought into contact with the contacts 5 and 5 provided on the oscillating body 4, as shown in FIG. is doing. The brush 14 is pressed in the brush holder 13 toward the contact 5 by a spring 15. 16
Is a pigtail for reducing resistance to power supply to the brush 14. A controller 17 controls the electric power supplied to the movable conductor wire 6 and the fixed coil 8 to drive the valve 1 at a predetermined timing. For this reason, signals from sensors provided in the engine are constantly input to the input terminal 17 ', and the optimum timing of valve drive is calculated from these signals. Reference numeral 18 is a battery for supplying electric power to the movable conductor line 6 and fixed coil 8, and 19 is a capacitor for supplying a large current to the movable conductor line 6 and fixed coil 8 within a short time. In addition, FIG.
It is a top view which shows the arrangement | positioning of the brush 14 and fixed magnetic pole 7'arranged around the circumference of.

The operation of the embodiment according to the present invention thus constructed will be described. When current is supplied to the fixed coil 8 wound around the fixed magnetic pole 7 ', magnetic flux is generated in the yoke 7 and the fixed magnetic pole 7', and this magnetic flux Φ is generated by the fixed magnetic pole 7 ', the yoke 7, the supporter 9', and the relay magnetic path. 9, the magnetic flux flows along a magnetic path whose root is the gap formed between the fixed magnetic pole 7 ′ and the relay magnetic path 9. The flow of this magnetic flux is shown by an arrow A in FIG.
If a current is supplied between the brushes 14 in this state, and this current flows in the direction of arrow B in FIG. 8 (hereinafter, this current direction is referred to as the forward direction), the same applies to the movable conductor line 6 arranged in the gap. Current flows in the direction. For this reason, a force according to Fleming's left-hand rule is generated in the movable conductor wire 6,
This force works to move the oscillating body 4 from the front side of the paper surface of FIG. This force then acts on the valve 1 and pushes it down to open the exhaust or intake port. The strength of the force acting on the valve 1 is adjusted by adjusting the amounts of the current flowing through the movable conductor wire 6 provided on the oscillator 4 and the current flowing through the fixed coil 8 wound around the fixed magnetic pole 7 '. .. For example, when trying to open the exhaust valve, a large internal pressure in the combustion chamber is applied to this, and thus a large force against this force is required. In the present invention, at the initial stage of opening the exhaust valve, a large current is instantaneously supplied from the capacitor 19 to the movable conductor wire 6 and / or the fixed coil 8 to open the exhaust valve at once.

Further, after the valve is opened, the valve drive does not require a large driving force unlike when the valve is opened. In the present invention, the current flowing through the movable conductor line 6 is reduced and the driving force is adjusted. Although the valve stops for a predetermined time at the completely opened position, an electric current in the opposite direction is applied to the immediately preceding movable conductor wire 6 to apply a braking force to the movable conductor wire 6 to stop the valve smoothly.
After that, if a predetermined amount of forward current is applied to the movable conductor wire 6 to balance it with the force of the spring biasing in the closing direction, the valve stops at the fully open position.

At the stage of closing the valve 1, the direction of the current flowing through the movable conductor line 6 is reversed. Then, a short time before the valve is seated, a forward current is applied to the movable conductor wire 6 to exert a braking force on the valve, and the valve is softly seated on the valve seat 10. In this way, the valve opens and closes. During this time, the brush 14 is pressed by the spring 15 against the contact 5 of the rocking body 4 and is in sliding contact therewith. However, since the contactor 5 uses a wear resistant material, its wear is reduced. Further, such a contactor 5 has a good contact property with the carbon constituting the brush, and therefore has a small frictional force and a low resistance value, so that a large current can smoothly flow.

The controller 17 controls the direction and amount of the current flowing through the movable conductor wire 6 and the direction and amount of the current flowing through the fixed coil 8. Explaining an example of the control, the controller 17 constantly detects the engine load and the rotation phase of the engine during engine operation.
Then, the valve opening / closing timing and the lift amount corresponding to the engine load are calculated. Then, when the valve opening timing comes during the rotation of the engine, the controller 17 outputs an initial signal to execute a valve driving program (not shown) to supply a large current to the movable conductor line 6 to start the operation. Open the valve. After the valve is opened at the initial stage, the amount of current flowing through the movable conductor wire 6 is reduced and the valve is opened with a predetermined lift amount. Next, when closing the valve, a braking force is applied to the fixed coil 8 before the valve is seated, and the valve is softly seated on the valve seat 10.

[0018]

As described in detail above, according to the present invention, since the oscillating body is formed by laminating the thin flat electric conductor wires in the cylindrical ceramics, the ampere turn of the oscillating body is formed. Can be secured large, and since the rocking body has no iron core, it is lightweight and can generate a large driving force. In addition, since a ceramic green sheet and a thin metal plate formed by punching electric conductor wires are laminated, they are curved in an arc shape, and the curved semi-finished product is fired to form an oscillator. The oscillator can be easily manufactured.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing an embodiment of the present invention.

FIG. 3 is a perspective view of an oscillator.

FIG. 4 is an exploded perspective view of an oscillator.

FIG. 5 is a perspective view of an oscillator.

FIG. 6 is a partial perspective view showing a lower portion of the oscillator.

FIG. 7 is a block diagram showing electrical connection of the present invention.

FIG. 8 is a top view showing the arrangement of brushes and fixed magnetic poles arranged around the oscillator.

[Explanation of symbols]

 1 …… Valve 2 …… Valve shaft 3 …… Cotter 4 …… Oscillator 5 …… Contactor 5 ′ …… Energizing wire 6 …… Movable conductor wire 7 …… Yoke 7 ′ …… Fixed magnetic pole 8 …… Fixed coil 9 ... Relay magnetic path 9 '... Supporter 10 ... Valve seat 11 ... Bushing 12 ... Cylinder head 13 ... Brush holder 14 ... Brush 15 ... Spring 16 ... Pigtail 17 ... Controller 18 ... Battery 19 ...... Capacitor 20 ...... Contact material 21 ...... Contact material 22 ...... Core 23 ...... Core 24 ...... Coil conductor 25 ...... Inner contact terminal 26 ...... Outer contact terminal 27 ...... First coil plate 28 ...... Green Sheet 29 …… Coil conductor 30 …… Internal contact terminal 31 …… Second coil plate 32 …… Plate-like body

Claims (2)

[Claims] 1. In an engine valve drive device, a rocking body, in which a thin flat plate-shaped electric conductor wire is laminated in a cylindrical ceramics, is connected to a valve, and the electric conductor wire and the chain of the rocking body are connected. A valve drive device for an engine, comprising: fixed magnetic poles that generate magnetic fluxes that intersect with each other. 2. A manufacturing process in which a ceramic green sheet and a thin metal plate formed by punching out electric conductor wires are laminated and curved into an arc shape, and the curved semi-finished product is fired to form an oscillator. A method of manufacturing a valve drive device for an engine, comprising: