JPH05332108A - Solenoid valve - Google Patents

Abstract

PURPOSE:To reduce change of inductance distribution caused at the time of actuating a movable coil to drive to open and close a solenoid valve by installing a compensating conductor on a pole face. CONSTITUTION:Compensating conductors 35, 35 made of conductive solid lubricating materials are installed on edge surfaces of magnetic poles 31, 31 to conduct magnetic flux from magnets 32, 33 of a field part 3, and between them, a movable coil 2 stored in a case 20 is arranged free to vertically slide. Thereafter, when the movable coil 2 is electrified, thrust is generated by a magnetic field generated on the movable coil 2 and flux linkage from the magnetic poles 31, 31 and the movable coil 2 is driven, but an inductance distribution characteristic changing in accordance with a coil position is reduced by an eddy current generated on the compensating conductors 35, 35.

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 arranged at an intake / exhaust port of a cylinder of an engine and is driven by an electromagnetic force.

[0002]

2. Description of the Related Art Conventionally, an intake / exhaust valve arranged in a cylinder is opened / closed by a mechanical operation such as a camshaft or a rocker arm driven by the rotation of a crankshaft. Because of its small size, various electromagnetic valves have been proposed in which mechanical operation is stopped and electromagnetic force is used to increase the degree of freedom.

As an electromagnetic valve of this kind, there is a valve control device disclosed in Japanese Patent Application Laid-Open No. 2-123210 by the applicant of the present invention. An intake / exhaust valve biased in a closing direction by a permanent magnet is used as an electromagnetic force. However, when driven by a magnetic attraction force, the stroke is short and the weight of the movable part increases.

Therefore, an electromagnetic valve having a voice coil motor (VCM) structure such as a dynamic speaker, which is improved by using a coil as a mover, has been attempted.

[0005]

The electromagnetic valve having the VCM structure described above does not have a magnetic pole in its movable portion, so that an increase in weight is suppressed. However, when the coil of the mover enters the magnetic circuit, the inductance distribution characteristic depends on the coil position. Changes to affect thrust characteristics.

Further, in order to strengthen the magnetic flux interlinking with the coil, it is desired to eliminate a gap having a large magnetic resistance, but a minimum gap must be left in the direction perpendicular to the movement direction of the valve to prevent contact. There's a problem.

The present invention has been made in view of the above problems, and an object thereof is to provide a moving coil type electromagnetically driven valve for suppressing the above-mentioned change in the inductance distribution and reducing the magnetic resistance in the gap portion. To provide.

[0008]

To achieve the above object, according to the present invention, a movable coil mounted above an intake / exhaust valve and concentratedly wound in a flat plate shape, and an interlinking magnetic flux in the movable coil are provided. In an electromagnetically driven valve having a field unit having a magnetic pole communicating with the movable coil, the electromagnetically driven valve being opened / closed by controlling energization to the movable coil, and having conductivity that slides with the movable coil on an end face of the magnetic pole facing the movable coil. Provided is an electromagnetically driven valve to which a compensation conductor made of a solid lubricant is attached.

[0009]

Since the compensation conductor made of a conductive solid lubricant is attached to the end faces of the magnetic poles sandwiching the movable coil and the case of the movable coil is slid, the change in the inductance distribution is suppressed by the eddy current generated in the compensation conductor. Further, the gap having a large magnetic resistance is reduced, the interlinkage magnetic flux is strengthened, and the thrust is increased.

[0010]

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

FIG. 1 is a top view and a vertical sectional view showing an embodiment of an electromagnetically driven valve according to the present invention. In FIG. 1, reference numeral 1 is an electromagnetic valve, the stem 11 of which is vertically reciprocally supported by a valve guide 12 so that when the valve is closed, suction /
The valve portion 13 is in close contact with the exhaust port to shut off the flow path.

A fixing member 14 is provided above the stem 11.
An upper seat 16 that supports the upper end of the spring 15 is attached through the above, and a connector 17 to which a case of a movable coil described later is connected is provided above the upper seat 16. The spring 15 pushes up the electromagnetic valve 1 in the closing direction by its elastic force.

Reference numeral 2 denotes a movable coil, which is concentratedly wound in the shape of a rectangular flat plate and accommodated in a case 20 as shown in FIG. 2. The magnetic flux interlinks with the horizontal winding portions of the upper side 2a and the lower side 2b. And a magnetic force generated by energizing the movable coil 2 generate a vertical thrust.

Reference numeral 3 denotes an upper magnetic field portion, which is the upper side 2a of the movable coil 2.
The magnetic flux is linked to the winding part of the core part 30. The core part 30 includes a pair of inner magnetic poles 31, a pair of magnets 32, a pair of outer magnetic poles 33, and a yoke 34, and usually a gap is formed. Compensation conductors 35 made of a solid lubricant are provided on opposite surfaces of the inner magnetic pole 31, and are formed so as to slide on both side surfaces of the movable coil 2 above the case 20. And solid lubricant is calcium phosphorus
A graphite solid lubricant impregnated with aluminum, which has conductivity and thus generates an eddy current in a changing magnetic field, and also has thermal conductivity, which causes heat generation due to copper loss of the sliding movable coil 2. Is to be dissipated.

Reference numeral 36 is a pair of windings wound around the yoke 34 and is energized so as to strengthen the magnetic flux that links the upper side 2a of the movable coil 2.

Reference numeral 4 denotes a lower field part, which is a lower side 2b of the movable coil 2.
The magnetic flux is linked to the part of the core part 40. The core part 40 has an inner magnetic pole 41, a magnet 42, an outer magnetic pole 43, a yoke 44, and a winding wire 4.
6 is used to form the upper magnetic field portion 3 substantially in the same manner as the upper magnetic field portion 3 described above. The second case 20 is configured to slide on the lower side surface portion.

Then, the polarities of the magnets of the upper field magnet portion 3 and the lower field magnet portion 4 and the directions of the magnetic fields generated in the windings by energization are set to the upper and lower directions opposite to each other, and the upper side 2a and the lower side of the movable coil 2 are set. It is dealt with that the currents flowing to 2b and 2b are opposite to each other.

Next, the operation of this embodiment constructed as described above will be explained. When the solenoid valve 1 is opened and closed, the winding 3
A current in a predetermined direction is passed through 6 and 46 to strengthen the magnetic flux that links the moving coil 2. On the other hand, the electromagnetic force of the movable coil 2 is generated by the electromagnetic force of the magnetic flux interlinking with the magnetic field generated by the current and the electromagnetic valve 1 is driven.

In this case, compensation conductors 35 and 45 are provided at the contact portions of the upper and lower magnetic field portions with the movable coil, and eddy currents generated in the compensation conductors 35 and 45 when the movable coil 2 moves. A strong thrust can be obtained because the thrust distribution by the electromagnetic force is stabilized by reducing or equalizing the inductance distribution of.

Further, the heat generated by the copper loss caused by energizing the movable coil 2 is radiated by the thermal conductivity of the sliding compensation conductors 35 and 45, and the temperature rise of the movable coil 2 is suppressed. Become.

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

[0022]

According to the present invention as in the above embodiments,
Since the compensating conductor made of a conductive solid lubricant is provided between the moving coil and the magnetic pole to slide the moving coil, the eddy current generated in the compensating conductor suppresses the change in the inductance distribution characteristic due to the coil position, and the thrust force is reduced. The effect that the characteristics are improved is obtained.

Further, according to the present invention, since the movable coil is slid, the gap is reduced, the increase of the magnetic resistance is suppressed, and the heat generated in the movable coil due to the copper loss is dissipated by the heat conduction of the compensation conductor. ..

[Brief description of drawings]

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

FIG. 2 is an explanatory diagram showing a main part of a field part and a movable coil in the present embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Electromagnetic valve 2 ... Moving coil 3 ... Upper field part 4 ... Lower field part 31 ... Magnetic pole 35 ... Compensation conductor

Claims (2)

[Claims] 1. A movable coil, which is mounted above an intake / exhaust valve and is concentratedly wound in a flat plate shape, and a magnetic field portion having magnetic poles for passing an interlinking magnetic flux to the movable coil. In an electromagnetically driven valve that is driven to open and close by controlling energization, an electromagnetically driven valve characterized in that a compensation conductor made of a conductive solid lubricant that slides on the movable coil is attached to the end face of the magnetic pole facing the movable coil. valve. 2. The electromagnetically driven valve according to claim 1, wherein the compensation conductor is made of a material in which a calcium phosphorus / graphite solid lubricant is impregnated with aluminum.