JPS63140653A - Electromagnetic driving actuator - Google Patents

Abstract

PURPOSE:To miniaturize a yoke, by composing a magnetic pass on a surface crossed in the driving direction of a coil. CONSTITUTION:An 'E'-formed yoke is composed of a center yoke 4, a side yoke 2, and an outer yoke 3; on the surface of the side yoke 2 confronted with the center yoke 4, a permanent magnet 1 is set. Magnetic flux generated by the permanent magnet 1 is crossed on the surfaces Z, X of a coil 6, and through a void section 5 and a magnetic shield member 7, the flux is infiltrated into the center yoke 4 and is returned to the permanent magnet 1 through the outer yoke 3 and the side yoke 2. When current is supplied to the coil 6, then a driving force is generated in the direction crossed on axes Y, Z including the closed magnetic circuit of a magnetic circuit, namely, in the direction of an axis X.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electromagnetically driven actuator.

[Conventional technology]

FIG. 4 is a perspective view of a conventional electromagnetic drive actuator as disclosed in, for example, Japanese Patent Application No. 58-133670, and FIG. 5 is an explanatory diagram of its operation.

In the figure, +11 is a permanent magnet that generates magnetic flux, (21
1 is an outer yoke, (3) is a side yoke, (4) is a center yoke, (5) is a gap, and 161 is a coil that provides a driving force when energized.

In the electromagnetically driven actuator configured in this way, the magnetic flux generated by the permanent magnet 111 passes through the gap +51 while crossing the coil (6), as shown by the broken line in FIG. ), side yoke (3
) to the outer yoke (2 pieces) and return to the permanent magnet (11) (forms a closed magnetic path, and by energizing the coil +61, a driving force in the direction shown by the arrow in the figure can be obtained. The figure shows the flow of magnetic flux only on one side for simplicity.

[Problem that the invention seeks to solve]

A conventional electromagnetic drive actuator is configured as described above, and the total magnetic flux generated by the electromagnet (1) passes through the center yoke (4), outer yoke (2), and side yoke (3), so the magnetic flux density is high. , the cross-sectional area of each of these yokes had to be increased.

This became more noticeable as the distance the coil (6) moved became longer. Also, inside the coil (6) there is a center yoke (
4) has a penetrating structure, so the width has become larger.

This invention was made to solve the above-mentioned problems, and an object thereof is to obtain an electromagnetic drive actuator that can be downsized.

[Means for solving problems]

The electromagnetic drive actuator according to the present invention includes an E-shaped yoke having a center yoke, side yokes provided on both sides of the center yoke, and an outer yoke connecting the three, and two gaps formed on both sides of the center yoke. A magnetic circuit consisting of a magnet that is inserted into the two air gaps astride the center yoke, intersects with the magnetic flux generated from the magnet, and is driven in a direction that intersects with a plane containing the closed magnetic path of the magnetic circuit when energized. It is equipped with a coil arranged to obtain a force, and a magnetic shielding material provided in the coil part that generates a driving force in one direction of the coil and a driving force in the opposite direction.

[Effect]

Since the magnetic circuit in this invention forms a magnetic path on a plane that intersects the driving direction of the coil, the magnetic flux passing through the unit area of the yoke is only the magnetic flux generated per unit area of the magnet, which is different from the conventional magnetic circuit. The yoke can be made smaller compared to the conventional one. Further, the magnetic shielding material prevents the generation of a driving force in one direction of the coil, in other words, a driving force in the direction opposite to the direction in which the driving force is desired to be generated.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view showing an electromagnetic drive actuator according to an embodiment of the present invention, and FIG. 2 is an explanatory diagram of its operation. In this example, an E-shaped yoke is formed by the center yoke (4), the side yokes (2) provided on both sides of the center yoke, and the outer yoke (3) that connects these three, and the center yoke (4) of the side yoke (2) ) A permanent magnet +I+ is arranged on the opposite surface to constitute a magnetic circuit. coil(
61 straddles the center yoke (4), is inserted into two air gaps +51 K formed on both sides of the center yoke (41), and is arranged so as to intersect the magnetic flux generated from the magnet (11). (7) is a magnetic shielding material made of a ferromagnetic material such as iron.

In the electromagnetically driven actuator configured in this way, the magnetic flux generated by the permanent magnet (1) passes through the gap (5) while intersecting the zx plane of the coil (61), as shown by the broken line in FIG. Furthermore, a closed magnetic path is formed in the YZ plane such that the magnetic shield material (7) passes through the center yoke (4), the outer yoke (3) passes through the side yoke (2), and then returns to the permanent magnet (11). On the other hand, coil 1
When energized to 6+, the surface including the closed magnetic path of the magnetic circuit (y
A driving force is generated in a direction intersecting (orthogonal to in this example) the z-plane), that is, in the X-axis direction.

In this case, the magnetic flux passing through the unit area of the yoke +21, [31, (41) is only the magnetic flux generated per unit area of the permanent magnet (11), so the magnetic flux density increases regardless of the moving distance of the coil (6). Compared to the conventional example shown in FIGS. 4 and 5, the yoke is +21, +31, (4
1 can be made smaller. In addition, by providing the magnetic shielding material (7) on the coil portion of the coil (6) that generates a driving force in one direction, that is, in the opposite direction to the desired direction, it prevents the magnetic flux from intersecting that coil portion and vice versa. This prevents the generation of driving force in the direction. In addition, in FIG. 2, only the magnetic flux generated from one permanent magnet fi+ is shown for the sake of simplicity.

3a and 3b are plan views schematically showing the arrangement relationship between the magnetic circuit and the coil of an electromagnetically driven actuator according to another embodiment of the present invention, and the broken lines in each figure indicate magnetic flux. In these embodiments as well, the coil (6) is driven in a direction perpendicular to the plane including the closed magnetic path of the magnetic circuit, that is, the plane of the drawing.

The same effects as the embodiment shown in FIG. 2 can be obtained.

Incidentally, in each of the above embodiments, the case where the magnet is a permanent magnet fil has been described, but an electromagnet may also be used, and the same effects as in the above embodiment can be obtained.

〔Effect of the invention〕

As described above, according to the present invention, there is provided an E-shaped yoke having a center yoke, side yokes provided on both sides of the center yoke, and an outer yoke that connects the three, and two yokes formed on both sides of the center yoke. A magnetic circuit consisting of magnets placed in each air gap, inserted into the two air gaps across the center yoke, intersects with the magnetic flux generated from the magnet, and intersects with a surface including the closed magnetic path of the magnetic circuit when energized. It is equipped with a coil arranged to obtain driving force in one direction, and a magnetic shielding material provided on the coil part that generates driving force in one direction and the opposite direction of this coil, making it possible to miniaturize electromagnetic drive. actuator can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing an electromagnetic drive actuator according to an embodiment of the present invention, FIG. 2 is an explanatory diagram of its operation, and FIG. 3 a
, b are front views schematically showing the arrangement relationship between a magnetic circuit and a coil according to other embodiments of the present invention, FIG. 4 is a perspective view showing a conventional electromagnetic drive actuator, and FIG. 5 is an explanatory diagram of its operation. be. In the figure, 111 is a permanent magnet, (2) is an outer yoke, (3) is a side yoke, (4) is a center yoke,
(5) indicates a gap, C6 indicates a coil, and (7) indicates a magnetic shielding material. Note that the same reference numerals in each figure indicate the same or equivalent parts.

Claims (2)

[Claims] (1) Magnetism consisting of an E-shaped yoke having a center yoke, side yokes provided on both sides of the center yoke, and an outer yoke that connects the above three, and magnets placed in two gaps formed on both sides of the center yoke. the circuit, straddling the center yoke and inserting it into the two gaps;
A coil arranged so as to intersect the magnetic flux generated from the magnet and obtain a driving force in a direction intersecting the plane including the closed magnetic path of the magnetic circuit when energized, and a driving force in one direction of this coil and a driving force in the opposite direction. An electromagnetic drive actuator equipped with a magnetic shield material in the coil part that generates force. (2) The electromagnetic drive actuator according to claim 1, wherein a direction intersecting a plane including the closed magnetic path of the magnetic circuit is a direction substantially perpendicular to the plane.