JPH0677046A - Repulsion type electromagnetic magnet - Google Patents

Abstract

PURPOSE:To obtain a repulsion type electromagnetic magnet, which is further improved its operating characteristics and at the same time, is simple in structure and is low cost. CONSTITUTION:A fixing side of a repulsion type electromagnetic magnet is constituted of a yoke 1, a coil 2, a fixed core 3 and a parallel magnetic material part 4 and a movable core 5 of the magnet is constituted of a first magnetic pole piece 6, a permanent magnet 7, a second magnetic pole piece 8 and a non-magnetic material rod 9. When a current is not made to flow through the coil 2, the magnetic flux of the magnet 7 is shunted into magnetic fluxes phia and phih and the core 3 sucks the core 5. When a current is made to flow through the core 2, a magnetic flux phi1 is induced, a repulsive force is generated between the cores 3 and 5 and the core 5 is separated from the core 3. When the current conduction through the coil 2 is stopped, the core 5 returns. As the magnetoresistance of a magnetic path of the magnet 7 is reduced by the actions of the part 4 and the piece 8, the repulsion type electromagnetic magnet is constituted so as to obtain a high-sensitivity repulsive force.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a repulsive electromagnet, and more particularly to a repulsive electromagnet which utilizes the repulsive force of an electromagnet and a permanent magnet.

[0002]

2. Description of the Related Art The inventor of the present invention has proposed an electromagnet in Japanese Unexamined Patent Publication No. 3-175153, which uses a permanent magnet for a movable iron core and generates an electromagnetic repulsive force between the fixed iron core and the movable iron core when the electromagnet is energized. is doing.

[0003]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a repulsion type electromagnet which simplifies the structure while further improving the repulsion operation characteristic of the electromagnet utilizing the electromagnetic repulsion force of the above-mentioned prior art. And

[0004]

DISCLOSURE OF THE INVENTION The present invention is to further improve the repulsive action characteristic of a conventional repulsive electromagnet, and is characterized in that a yoke, a fixed iron core fixed to the yoke, and an end surface of the fixed iron core are attracted to the fixed iron core. A movable iron core having a permanent magnet magnetized in the axial direction and a coil wound around the fixed iron core, and the fixed iron core and the movable iron core attracted by the magnetic flux of the permanent magnet are energized to the coil. It was applied to the repulsion type electromagnet which is separated by the above, and adopted the following technical means. That is,
A parallel magnetic body portion parallel to the moving direction of the movable iron core is provided at an end of the yoke opposite to the fixed iron core, and a magnetic pole piece opposed to the parallel magnetic body portion at a non-adsorption end of the movable iron core with a minute gap. The repulsion-type electromagnet is characterized by being provided with.

A part of the yoke may be the parallel magnetic body portion.

[0006]

2A and 2B are views for explaining the operation of one embodiment of the present invention. FIG. 2A shows a state where the coil is not energized and the fixed core and the movable core are attracted, and FIG. 2B shows the coil. The figure shows the state where the fixed iron core and the movable iron core are separated by energization. Figure 2
In (a), 1 is a yoke, 2 is a coil, 3 is a fixed iron core, 4 is a parallel magnetic material portion, 5 is a movable iron core, and the first magnetic pole piece 6, the permanent magnet 7, the second magnetic pole piece 8 and It is composed of a non-magnetic rod 9.

If the coil 2 is not energized,
The magnetic flux of the permanent magnet 7 is divided into φ _a and φ _b , and as _a result, the fixed iron core 3 and the movable iron core 5 are attracted as shown in FIG.
Retained. When the coil 2 is energized in the state of FIG. 2 (a), a magnetic flux φ _i is induced as shown in FIG. 2 (b), and the action between the magnetic fluxes φ _a and φ _i causes a gap between the movable iron core 5 and the fixed iron core 3. A repulsive force is generated in the movable iron core 5 and the movable iron core 5 is separated from the fixed iron core 3. If the energization of the coil 2 is stopped, FIG.
To the state of.

FIG. 4 is a diagram for explaining the operation of another embodiment of the present invention. FIG. 4 (a) is a state in which the coil is not energized and the fixed core and the movable core are attracted, and FIG. 4 (b) is the coil. The state where the fixed iron core and the movable iron core are separated from each other by energizing Figure 4
(A) and FIG. 4 (b) are respectively FIG. 2 (a) and FIG.
Corresponding to (b), _a repulsive force is generated between the movable iron core 5a and the fixed iron core 3a by the action of the magnetic fluxes φ _a and φ _i , the movable iron core 5 a is separated from the fixed iron core 3 a, and the energization of the coil 2 is stopped. In this case, the state shown in FIG. 4 (a) is restored.

As shown in FIG. 5, the electromagnetic force of the electromagnet acting between the fixed iron core and the movable iron core changes exponentially with respect to the change in the separation distance between the fixed iron core and the movable iron core. It is well known that the shorter the length, the sharper the increase.
However, in the conventional attraction type electromagnet, the above-mentioned separation distance is maximum at the attraction operation start point and becomes zero at the operation completion point. Therefore, in the conventional attraction type electromagnet, various studies have been conducted to increase the attraction force at the starting point of the attraction operation where the attraction force is weakest.

The repulsive electromagnet of the present application changes the way of thinking so that the distance between the fixed iron core and the movable iron core is zero, that is,
The operation is started when the fixed iron core and the movable iron core are attracted to each other, and the operation is completed when the distance between them is maximized. Therefore, the maximum repulsive force can be generated when the operation of the electromagnet is started. In addition, when the coil is energized and the fixed iron core and the movable iron core are separated from each other, if the coil current is switched in the opposite direction, a strong attractive force is generated between the fixed iron core and the movable iron core, and the movable iron core moves at high speed. It can be adsorbed on a fixed iron core.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is an explanatory view of a cross section of an embodiment of the present invention.
Shown in (a) and (b). The fixed side comprises a cylindrical yoke 1, a coil 2, a fixed iron core 3, and a parallel magnetic body portion 4, and a movable iron core 5 has a cylindrical permanent magnet 7 magnetized in the axial direction as a first magnetic pole piece 6 and a second magnetic pole. It was sandwiched by the pieces 8 and the non-magnetic rod 9 was inserted therethrough. Further, the abutting surfaces of the fixed iron core 3 and the movable iron core 5 (first magnetic pole piece 6) are formed with concave and convex surfaces that fit with each other.

When the coil 2 is not energized, as shown in FIG.
As shown in (a), the end face of the first magnetic pole piece 6 and the end face of the fixed iron core 3 are attracted by the permanent magnet 7. When the coil 2 is energized, the movable core 5 separates from the fixed core 3 and
The process moves to (b), and the length of the parallel portion of the parallel magnetic body portion 4 is set so that the peripheral edge of the second magnetic pole piece 8 moves while facing the parallel magnetic body portion 4 during this period. With this configuration, the magnetic resistance of the magnetic path of the permanent magnet 7 is reduced.

When the present embodiment is applied to a relay mounted on a printed circuit board, the first magnetic pole piece 6 and the second magnetic pole piece 8 of the movable iron core 5 are omitted because of their small size. Thus, the movable iron core 5 may be composed of only the strong permanent magnet 7. 3A and 3B are explanatory views of the cross section of another embodiment. Although this has a slightly different configuration from that shown in FIG. 1A, the operation and effect are the same. In this example, FIG.
A part of the yoke 1 is used instead of the parallel magnetic body part 4 of (a).

A disk-shaped magnetic pole piece 10 is provided on the end surface of the fixed iron core 3a.
Fixed. That is, the pole piece 10 is provided so as to contact the fixed iron core 3 a and the coil bobbin 12. On the other hand, the movable core 5a is formed by sequentially superimposing an annular permanent magnet 7a and an annular magnetic pole piece 14 on a non-magnetic component consisting of a disc 11 and a rod 13. In the magnetic pole piece 14, the peripheral edge of the magnetic pole piece 14 faces the inner peripheral surface of the yoke 1 from the state in which the fixed iron core 3a and the movable iron core 5a are attracted to each other until the fixed iron core 3a and the movable iron core 5a are separated from each other. It is configured to do.
Reference numeral 15 is a non-magnetic material guide.

2B, the magnetic pole pieces 8 are respectively arranged on the yoke end face side of the parallel magnetic body portion 4 and on the yoke end face side in FIG. 4B at a position where the movable iron core and the fixed iron core are maximally separated from each other.
By providing a stopper that abuts against the magnetic pole piece 14 and stops the movable iron core, the movable iron core does not recover and remains in the separated state even when the coil energization is stopped in a state where the movable iron core and the fixed iron core are separated. Can be maintained (latching). In order to restore the movable iron core, the energization of the coil may be reversed.

[0016]

The present invention has the following excellent effects. a A small and highly sensitive electromagnet can be manufactured. b The structure is simple, and it is easy to mass-produce robust electromagnets. c An inexpensive electromagnet can be manufactured.

D No biasing spring is required.

[Brief description of drawings]

FIG. 1 is an explanatory view of a cross section of an embodiment of the present invention.
1A shows a state where the coil is not energized and the fixed iron core and the movable iron core are adsorbed, and FIG. 1B shows a state where the coil is electrified and the fixed iron core and the movable iron core are separated from each other. .

FIG. 2 is an explanatory view of the operation of FIG. 1, where FIG. 2 (a) shows a state where the coil is not energized and the fixed core and the movable core are adsorbed, and FIG. 2 (b) shows the coil. The figure shows a state in which the fixed iron core and the movable iron core are separated from each other when electricity is applied.

FIG. 3 is an explanatory view of a cross section of another embodiment of the present invention, and FIG. 3 (a) shows a state where the coil is not energized and the fixed core and the movable core are adsorbed, and FIG. b) is shown in FIG.
It is an AA arrow sectional drawing of (a).

FIG. 4 is an explanatory view of the operation of FIG. 3, in which FIG. 4 (a) shows a state in which the fixed core and the movable core are attracted without energizing the coil, and FIG. 4 (b) shows the coil. The figure shows a state in which the fixed iron core and the movable iron core are separated from each other when electricity is applied.

FIG. 5 is a graph showing the relationship between stroke length and electromagnetic force of an electromagnet.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 yoke 2 coil 3, 3a fixed iron core 4 parallel magnetic body part 5, 5a movable iron core 6 first magnetic pole piece 7, 7a permanent magnet 8 second magnetic pole piece 9 nonmagnetic rod 10 magnetic pole piece 11 nonmagnetic disk 12 bobbin 13 non-magnetic rod 14 magnetic pole piece 15 guide φ _a , φ _b magnetic flux of permanent magnet φ _i magnetic flux when coil is energized

Claims (2)

[Claims] 1. A yoke, a fixed iron core fixed to the yoke, a movable iron core having an axially magnetized permanent magnet whose end face is attracted to the fixed iron core, and a movable iron core wound around the fixed iron core. A repulsive electromagnet that is composed of a coil and separates the fixed iron core and the movable iron core, which are attracted by the magnetic flux of the permanent magnet, by energizing the coil, wherein a movable core is provided at an end of the yoke opposite to the fixed core. A repulsive electromagnet, comprising: a parallel magnetic body portion parallel to the movement direction; and a magnetic pole piece facing the parallel magnetic body portion with a minute gap provided at an anti-adsorption end of the movable iron core. 2. The repulsive electromagnet according to claim 1, wherein a part of the yoke is the parallel magnetic body portion.