JPH0536520A - Electromagnet - Google Patents

Abstract

PURPOSE:To increase sensitivity, reduce size and weight and lengthen a service life of an electromagnet which is activated by overlapping a magnetic flux caused by supplying power to a coil and a magnetic flux of a permanent magnet. CONSTITUTION:1 is a yoke, 2 is a fixed iron core, 3 is a coil, 4 is a plunger, 5 is a permanent magnet, 6a is a pole piece, 7 is a bobbin, 7a is a non-magnetic body, and 8 is a cylindrical piece. Conventionally, since the permanent magnet 5 and the pole piece 6a are placed oppositely to the coil 3, thus a magnetic flux due to power supply to the coil 3 and a magnetic flux of the permanent magnet 5 have increased frictional resistance with a guide pipe (not shown) provided around the plunger 4 as constant suction force functions in a radial direction with respect to the plunger 4 due to a fluctuation in part machined sizes. Thus the arrangement of the permanent magnet 5, the pole piece 6a and a bottom plate 1a is changed in this invention.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a solenoid valve, a solenoid relay,
The present invention relates to an electromagnet used for an electromagnetic operation mechanism or the like.

[0002]

2. Description of the Related Art For example, an electromagnet shown in FIG. 3 is used as an electromagnet for energizing a coil to generate a magnetic flux in a magnetic path and a magnetic flux produced by a permanent magnet in the same magnetic path so as to act on each other to improve attraction characteristics. Has been done. This electromagnet has a yoke 1,
The fixed iron core 2, the coil 3 wound around the bobbin 7, the plunger 4, the magnetic pole piece 6 for guiding the magnetic flux of the permanent magnet 5 to the plunger 4 side, the bottom plate 1a, etc. Are separated by a spring (not shown).

4 (a) and 4 (b) are views for explaining the action of magnetic flux. The solid line in FIG. 4A indicates the magnetic flux of the permanent magnet 5 when the fixed iron core 2 and the plunger 4 are separated from each other, and the coil 3 is energized to generate the magnetic flux as indicated by the dotted line in the figure. And the interaction of each magnetic flux,
As shown in (b), the plunger 4 is attracted to the fixed iron core 2.

In order to separate the plunger 4 and the fixed iron core 2 from each other, it is sufficient to energize the coil in the opposite direction so that the magnetic flux shown by the dotted line in FIG. 4 (b) is generated.

[0005]

However, the above-mentioned conventional electromagnets have the following problems. Figure 4
As shown in FIGS. 4A and 4B, the magnetic flux of the permanent magnet 5 and the magnetic flux and the attractive force generated when the coil is energized are both in a direction (radial direction) orthogonal to the axis of the plunger 4. There is a part that acts on. Therefore, due to variations in the processing accuracy of each component and the like, a suction force acts on the plunger 4 in one radial direction, so that the plunger 4 and the plunger 4 are arranged so as to surround them. There is a problem that the frictional resistance with the guide pipe increases and the suction characteristic is deteriorated or the life of the plunger 4 is shortened.

An object of the present invention is to solve the above problems and to provide an electromagnet having high sensitivity, small size, light weight and long life.

[0007]

The present invention adopts the following technical means in order to solve the above problems. (A) A cylindrical yoke whose one end is closed by the bottom plate and the other end is opened, (a) a fixed core fixed in the yoke through a non-magnetic material at the center of the bottom plate, and (c) a magnetic pole surface that abuts the bottom plate. And a permanent magnet magnetized in the axial direction, and a magnetic piece that abuts on the other magnetic pole surface of the permanent magnet and surrounds the fixed iron core and is fixed to the fixed iron core. And a stator having a coil fixedly attached to the yoke by surrounding one end face with the end face of the fixed core; and a coil inserted into the coil bobbin hole and having one end face contacting and separating from the end face of the fixed core. A jar, a spring that applies a biasing force between the plunger and the fixed iron core, and a cylindrical piece that is fixed to the other end face of the plunger and that abuts the end face of a cylindrical yoke that has one end closed and the other end open. A disk-shaped piece, and a mover equipped with It consists, when the plunger is in contact with the fixed core, an electromagnet, characterized in that the end face of the cylindrical piece or disk-shaped piece is brought into contact with the cylindrical yoke end face is open.

Further, the attraction force characteristic of the electromagnet can be improved by forming the cylindrical piece and the abutting surface of the end surface of the cylindrical yoke on a partial conical surface inclined so as to be fitted to each other.

[0009]

Since the present invention is configured as described above, the magnetic flux of the permanent magnet and the magnetic flux and the magnetic attractive force generated when the coil is energized can be applied to the plunger parallel to the axial direction. That is, since the attraction force of the orthogonal component of the magnetic flux to the plunger can be eliminated, the attraction force in the axis orthogonal direction acting between the plunger and the guide pipe can be reduced. The frictional resistance between the guide pipe and the guide pipe is reduced, the attraction characteristic is improved, and a long-life electromagnet can be obtained.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is an explanatory view of a vertical sectional view of an embodiment of the present invention.
Shown in. The present invention relates to a bottom plate 1a provided on one end side of the yoke 1.
A circular hole is formed in the center of the fixed core 2 fixed to the yoke 1 via the non-magnetic body 7a, the S pole surface is brought into contact with the bottom plate 1a, and the fixed core 2 is fixed via the non-magnetic body 7a. A disk-shaped magnetic piece 6a, which is fixed to the fixed iron core 2 and surrounds the fixed iron core 2 while being in contact with the permanent magnet 5 which is disposed surrounding the magnet 5 and which is magnetized in the axial direction. One end surface of the plate-shaped magnetic piece 6a is brought into contact with the disk surface, and the stator is provided with the coil 3 and the like that is fixed in the yoke 1 and surrounds the fixed iron core 2. A plunger 4 is arranged to come into contact with and separate from the end face of the iron core 2, and a cylindrical piece 8 fixed to the other end face of the plunger 4 and having one end closed and the other end abutting the opened cylindrical yoke end face. When the plunger 4 comes into contact with the fixed iron core 2, the cylindrical piece 8 Surface is configured to abut the cylindrical yoke end face is open. The cylindrical piece 8 may be a disk-shaped piece.

It is desirable that the contact between the plunger 4 and the fixed iron core 2 and the contact between the end surface of the cylindrical piece 8 and the open end surface of the cylindrical yoke be the same, but in actual production of the electromagnet, Since there are variations in the processing accuracy of each part,
When either one abuts, the other one may have a minute gap. At this time, there may be a minute gap between the end surface of the coil 3 and the end surface of the cylindrical piece 8.

It should be noted that the surfaces of the permanent magnet 5 and the disk-shaped magnetic piece 6a opposite to the surface facing the fixed iron core 2 respectively have a minute gap between them and the yoke 1. this is,
This is because the divided flow rate of the magnetic flux of the permanent magnet 5 is efficiently guided to the yoke 1 and the fixed iron core 2. 2A and 2B are explanatory views of the action of magnetic flux. FIG. 2A shows a state where the fixed iron core and the plunger are separated from each other, and FIG. 2B shows a state where the fixed iron core and the plunger are attracted. . The operation is similar to that of FIG.

As is apparent from the comparison of FIG. 1 with the conventional example of FIG. 3, in the conventional example, the magnetic flux of the permanent magnet 5 and the magnetic flux and magnetic attractive force generated when the coil 3 is energized are both generated by the plunger 4. Although there is a portion that acts in a direction orthogonal to the axis, in the present embodiment, the magnetic flux of the permanent magnet 5 and the coil 3 are present.
All the magnetic fluxes generated when electricity is applied to the magnet can be applied in a direction orthogonal to the axis of the fixed iron core 2, and can be applied to the plunger 4 in parallel with the axial direction.

That is, according to the present invention, the plunger 4 is constructed so that a suction force acting in a direction orthogonal to the axis of the plunger 4 is not generated. Therefore, the magnetic flux in the direction perpendicular to the axis between the plunger and the guide pipe becomes small, and the frictional resistance between the plunger and the guide pipe can be reduced. Further, as shown in FIG. 1, when the abutting portion shape of the open end of the yoke 1 and the end portion of the cylindrical piece 8 is formed into a partial conical surface inclined so as to be fitted to each other, the inclination angle becomes smaller. The attractive force of the component perpendicular to the axis, which corresponds to the COSIN component, acts between both ends.By setting this inclination angle to a predetermined value, the attractive force of the component orthogonal to the axis is reduced, and the magnetic force between both ends is reduced. The magnetic reluctance of the path can be reduced.

[0015]

The present inventor has proposed a high-sensitivity electromagnetic actuator in Japanese Patent Application No. 60-6599. However, the present invention eliminates the attraction force of the orthogonal component of each magnetic flux to the plunger and Since it is possible to reduce the frictional resistance between the electromagnet and the guide pipe, it is possible to obtain an electromagnet having higher sensitivity, smaller size, lighter weight, and longer life.

[Brief description of drawings]

FIG. 1 is an explanatory view of a vertical section of an embodiment of the present invention.

FIG. 2 is a diagram for explaining the action of the magnetic flux of the present invention, FIG. 2 (a) shows a state where the fixed iron core and the plunger are separated, and FIG. 2 (b) shows an attraction of the fixed iron core and the plunger. It shows the state.

FIG. 3 is an explanatory view of a vertical section of a conventional example.

FIG. 4 is a diagram for explaining the action of magnetic flux in a conventional example. FIG. 4 (a) shows a state where the fixed iron core and the plunger are separated from each other, and FIG. 4 (b) shows a state where the fixed iron core and the plunger are attracted. It shows the state.

[Explanation of symbols]

1 York 1a Bottom plate 2 fixed iron core 3 coils 4 Plunger 5 permanent magnets 6 pole pieces 6a Disc-shaped magnetic piece 7 bobbins 7a Non-magnetic material 8 cylindrical pieces Solid line Magnetic flux of permanent magnet Dotted line Magnetic flux when energizing the coil

Claims (2)

[Claims] 1. A cylindrical yoke having one end closed by a bottom plate and the other end opened, a fixed iron core fixed in the yoke at the center of the bottom plate via a non-magnetic material, and one magnetic pole surface contacting the bottom plate. A permanent magnet magnet which is in contact with and surrounds the fixed iron core and is magnetized in the axial direction, and a magnet which is in contact with another magnetic pole surface of the permanent magnet and surrounds the fixed iron core and is fixed to the fixed iron core. A stator provided with a piece and a coil fixed to the end of the magnetic piece and having one end abutted to the end of the magnetic piece and surrounding the fixed iron core and fixed in the yoke; A plunger that comes into contact with and separates from the end face of the fixed iron core, a spring that applies a biasing force between the plunger and the fixed iron core, and one end that is fixed to the other end face of the plunger and that closes the other end. With a cylindrical piece or a disk-shaped piece that abuts the end surface of the cylindrical yoke An electromagnet comprising: a child ;; and when the plunger contacts the fixed iron core, the end surface of the cylindrical piece or the disk-shaped piece contacts the end surface of the opened cylindrical yoke. 2. The electromagnet according to claim 1, wherein the cylindrical piece and the abutting surface of the end surface of the cylindrical yoke are formed into a partial conical surface inclined so as to be fitted to each other.