JPH05288023A - Electromagnetic drive valve - Google Patents

Abstract

PURPOSE:To improve driving force by concentratedly winding a movable coil to drive a solenoid valve into a flat plate shape and constituting a magnetic circuit of corresponding magnetic gap in series. CONSTITUTION:Movable coils 4, 5 to drive an intake valve and an exhaust valve are concentratedly wound into squre flat plate shapes, and a magnet 22, an inner magnetic pole 23, and a magnet 24 for exciting gaps 26 and 27 to be interposed between them are combined together by means of an outer magnetic pole 25 so as to form an upper field magnetic part 2 in which an exciting magnetic circuit is formed in series, and a lower field magnetic part 2 of similar constitution is formed below it. In the case of driving solenoid valves for the purpose of intake and exhaust, electric power is supplied to the movable coils 4, 5, the movable coils are driven by electromagnetic force against the gaps to which strong magnetic flux is supplied by means of the magnetic circuit in series, and hence the intake valve and the exhaust valve are opened and closed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetically driven valve which is disposed at an intake / exhaust port of a cylinder of an engine and is opened / closed by being driven by an electromagnetic force.

[0002]

2. Description of the Related Art Conventionally, in intake and exhaust valves arranged in a cylinder, the rotation of a crankshaft is mechanically transmitted via a timing belt to open and close the intake and exhaust ports. Therefore, an electromagnetic valve that uses electromagnetic force to eliminate the mechanical relationship has been attempted.

In an electromagnetic valve driven by such an electromagnetic force, for example, a proposal shown in Japanese Patent Laid-Open No. 3-105006 and a dynamic case in which a mover connected to the valve has a plurality of magnetic poles and a dynamic valve are provided. There is an electromagnetic valve using a movable coil such as a voice coil of a speaker.

[0004]

According to the proposal disclosed in the above-mentioned former publication, the weight is large due to the magnetic poles in which the plurality of movable parts are arranged, which causes a problem in high-speed operation. Become. In the case of the latter voice coil type, problems such as disturbance of magnetic flux (amateur action) caused by magnetomotive force of the movable coil due to energization, attraction force acting with the central magnetic pole, and magnetic saturation due to the central magnetic flux occur. Further, in order to obtain a large driving force, it is sufficient to increase the electric energy passing through the moving coil, but there is a concern that the temperature will increase due to copper loss and the volume will increase due to the increase in the conductor diameter.

The present invention has been made in view of the above problems, and an object thereof is to employ a flat movable coil without using a heavy magnetic pole in a drive portion of an electromagnetic valve to straighten a magnetic flux. It is intended to provide an electromagnetic valve in which the driving force is increased by intersecting each other.

[0006]

In order to achieve the above-mentioned object, according to the present invention, it is provided in the intake and exhaust ports of the engine,
In an electromagnetically driven valve that is driven by energization of a movable coil arranged in a magnetic gap to open and close a flow path, each movable coil that is connected above an intake valve and an exhaust valve and is wound in a rectangular flat plate shape, An upper field magnet portion in which magnetic circuits for passing magnetic flux are formed in series in both air gaps in which the windings of the respective upper sides of these movable coils are arranged, and both air gaps in which the lower sides of the respective movable coils are arranged. There is provided an electromagnetically driven valve having a lower field magnet portion in which magnetic circuits each passing a magnetic flux are formed in series.

[0007]

The moving coils, which are concentratedly wound in the shape of a rectangular flat plate, are attached above the intake / exhaust valves, and the magnetic gaps in which these moving coils are arranged are the upper magnetic field portions corresponding to the upper sides of the moving coils. It is formed by the lower field part that is variable,
Further, since the magnetic circuit for exciting the air gap for driving the intake valve of the upper and lower field portions and the magnetic circuit for exciting the air gap for driving the exhaust valve are formed in series, respectively,
When driving the exhaust valve, the magnetic force generated by the permanent magnets and excitation windings can be used efficiently to obtain a strong driving force.
The drive mechanism is small and space can be effectively used.

[0008]

Embodiments of the present invention will now be described in detail with reference to the drawings.

FIG. 1 is a top view and a sectional view showing an embodiment of an electromagnetically driven valve according to the present invention. In FIG. 1, 1 is an electromagnetic valve and its stem 11 is a valve guide 12.
Is reciprocally supported up and down, and when the valve is closed, the valve portion 14 is seated on the valve seat 13 to close the flow path.

Reference numeral 2 denotes an upper magnetic field portion, which is a combination of upper magnetic fields on the intake side and the exhaust side. The core portion 20 has a pair of inner magnetic poles 21 and a pair of magnets 22 on the intake side. The pair of inner magnetic poles 23 and the pair of magnets 24 on the exhaust side are coupled by the pair of outer magnetic poles 25 to form a series magnetic circuit. A gap 26 for interposing the movable coil 4 on the intake side is provided therebetween, and a gap 27 for interposing the movable coil 5 on the exhaust side is provided between the pair of inner magnetic poles 23. The magnets 22 and 24 are magnetized so that a strong magnetic flux flows in the counterclockwise direction in the top view as shown in the drawing, and the inner magnetic pole 21 and the inner magnetic pole 23 are magnetized.
The winding 28 and the winding 29 wound around
An exciting current in the direction of strengthening the magnetic flux generated by the magnets 22 and 24 is supplied.

Reference numeral 3 denotes a lower magnetic field portion, which is a combination of the lower magnetic fields of the intake side and the exhaust side, and the structure thereof is the inner magnetic pole 31, the magnet 32, the outer magnetic pole 35 and the winding shown in the sectional view of FIG. In addition to the line 38, other magnets, magnetic poles, etc. are provided, and only the magnetization direction of the magnetic pole and the energization direction of the winding are different from the above-mentioned upper field magnet portion 2, and the shapes and the like are almost the same. A strong magnetic field is generated against the air gap 36. Therefore, the direction of the magnetic flux of the lower field magnet portion 3 is a clockwise magnetic flux when viewed from the top surface.

Next, FIG. 2 is a perspective view showing a movable coil, that is, the movable coil 4 on the intake side and the movable coil 5 on the exhaust side.
As shown in the drawing, both are formed by concentrated winding in a rectangular shape in a flat plate shape, and a connecting fork 42 made of a non-magnetic material is projected downward from the wire ring 41. Then, it is fixed to the electromagnetic valve 1 by an upper seat 16 which is joined by a fixing member 15 above the stem 11, and the lead wire from the coil 41 of the movable coil 4 is guided by the connecting fork 42 and the upper seat 16, and , Is drawn below the housing 18 by a double coil spring 17 that biases the electromagnetic valve 1 to a closed position.

Although the structure of the electromagnetic valve and the movable coil has been described with respect to the intake side as described above, the electromagnetic valve is coupled under the movable coil 5 on the exhaust side with almost the same structure. There is something.

Next, the operation of the present embodiment thus constructed will be described. When the electromagnetic valve 1 serving as an intake valve is opened, the air gap 26 of the upper magnetic field portion 2 and the air gap 36 of the lower magnetic field portion 3 are opened.
In order to strengthen the magnetic field in the initial stage of driving, currents in predetermined directions are passed through the windings 28, 28 and the windings 38, 38, respectively.

On the other hand, a current in the direction shown in the drawing is passed through the coil 41 of the movable coil 4 through the coil spring 17, and the electromagnetic force generated by the current and the magnetic flux in the gaps 26 and 36 drive the movable coil 4 downward. The electromagnetic valve 1 is moved downward through the connecting fork 42 and the upper seat 16 to open the valve.

At this time, although the direction of the current passing through the winding on the upper side of the movable coil 4 is opposite to the direction of the current on the winding on the lower side, the direction of the magnetic flux in the air gap 26 of the upper magnetic field portion 2 and the lower direction. Magnetic part 3
Since it is configured in the direction opposite to the direction of the space 36, the electromagnetic valve 1 is strongly driven by the addition of the respective upper and lower electromagnetic forces.

Next, when the electromagnetic valve which is connected to the lower portion of the movable coil 5 and serves as an exhaust valve, is driven downward similarly to the above description, in the present embodiment, it is movable on the intake side. The magnetic circuit that excites the air gap 26 corresponding to the coil 4 and the magnetic circuit that excites the air gap 36 corresponding to the movable coil 5 on the exhaust side are configured in series in the upper magnetic field portion 2, and both are movable. Since the magnetic circuit corresponding to the air gap on the lower side of the coil is formed in series by the lower field magnet portion 3, the magnetic fluxes for driving mutually strengthen each other, and a strong driving force is obtained when the electromagnetic valve is driven.

Although the present invention has been described with reference to the above embodiments, various modifications are possible within the scope of the gist of the present invention, and these modifications are not excluded from the scope of the present invention.

[0019]

According to the present invention as in the above embodiments,
Each movable coil that is connected to and driven by the intake / exhaust valve is concentratedly wound in the shape of a rectangular flat plate, and an upper field portion is formed by connecting in series a magnetic circuit that excites the air gap corresponding to the upper side of these movable coils. , The magnetic flux efficiently linked to the moving coils at right angles by the lower field part in series with the magnetic circuit that excites the air gap corresponding to the lower side, so it acts on the upper and lower wire loops when energizing these moving coils. The resulting electromagnetic force is added to form a powerful driving force, and the electromagnetic valve is effectively driven.

Further, according to the present invention, since the drive mechanism for the intake valve and the drive mechanism for the exhaust valve are arranged adjacent to each other, there is an advantage that the mechanism is downsized and the space above the cylinder is effectively utilized.

Further, in the present invention, since the winding for strengthening the magnetic field of the permanent magnet is provided, there is an effect that the driving force at the initial stage of valve opening and at the time of seating can be appropriately adjusted by controlling the energization of the winding.

[Brief description of drawings]

FIG. 1 is a top view and a sectional view showing an embodiment of an electromagnetically driven valve according to the present invention.

FIG. 2 is a perspective view showing a movable coil of this embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Electromagnetic valve 2 ... Upper field part 3 ... Lower field part 4, 5 ... Moving coil 22, 24 ... Magnet 26, 27 ... Air gap 28, 29 ... Winding

Claims (3)

[Claims] 1. An electromagnetically driven valve, which is provided at an intake / exhaust port of an engine and is opened / closed by being driven by energization of a movable coil arranged in a magnetic gap, is a square connected to an intake valve and an exhaust valve, respectively. A movable coil wound like a flat plate, and an upper magnetic field part in which magnetic circuits that pass magnetic flux through the air gaps in which the windings of the upper sides of these movable coils are arranged are formed in series. An electromagnetically driven valve, comprising: a lower field magnet portion in which magnetic circuits that pass magnetic flux are formed in series in both air gaps in which respective lower sides of the movable coils are arranged. 2. The electromagnetically driven valve according to claim 1, wherein each of the magnetic circuits has a permanent magnet and an excitation winding. 3. The electromagnetically driven valve according to claim 2, wherein energization of the exciting winding is controlled at the initial stage of valve opening and at the time of seating of the electromagnetic valve.