JPH0372605A - Monostable electromagnet - Google Patents

Abstract

PURPOSE:To enable an armature to be applied to a biased spring load on an element such as an electromagnetic contactor, etc., without using an operating spring at all by a method wherein a permanent magnet with the magnetizing direction thereof almost in parallel with the travelling direction of a connecting and disconnecting part is arranged near the connecting and disconnecting part of an armature. CONSTITUTION:A coil 2 is wound around a piece of a yoke 1 of almost semicircular shape while an armature 3 has a pivotally supporting part 5 magnetically coupled with one end part of the yoke 1 as well as a connecting and disconnecting part 7 connecting and disconnecting to the other end part 8 of the yoke 1 by oscillation. A permanent magnet 4 is fixed to the other ends 8 and arranged near the connecting and disconnecting part 7 while the magnetizing direction of the permanent magnet 4 is almost in parallel with the travelling direction of the part 7 on the other hand the magnet 4 is formed longer than the travelling range of the part 7. In the resetting state of an electromagnet, the magnetic flux PHI1 of the permanent magnet 4 runs in the armature 3, the yoke 1 and an auxiliary yoke 9 while a partial magnetic flux PHI2 runs in the armature 3, the auxiliary yoke 9 but hardly attracting the armature 3 in the resetting direction thereof so that the armature 3 may be applied to any biased spring load without using any conventional operating spring at all.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a monostable electromagnet that is applied to electromagnetic contactors, electromagnetic relays, etc. for switching on and off three-phase motors.

[Conventional technology]

Conventional monostable electromagnets of this type have generally been so-called non-polar electromagnets that do not include a permanent magnet in their magnetic circuits, such as Krasova electromagnets. Although this non-polar electromagnet is low cost, only the magnetic flux generated by the coil can be used to drive the armature, so it is necessary to increase power consumption in order to obtain a certain range of attractive force.

On the other hand, in recent years, polarized electromagnet devices in which a permanent magnet is included in the magnetic circuit have been proposed in order to reduce the power consumption of electromagnets (e.g., Japanese Patent Publication No. 17333/1983, Publication No. 17333/1983,
No. 10327).

[Problem to be solved by the invention]

The monostable electromagnet disclosed in Japanese Patent Publication No. 62-17333 can use the magnetic flux of the permanent magnet for the driving force of the armature, so it can consume less power than the non-polar type when obtaining a certain range of attractive force. However, because of its bistable electromagnetic structure, it was unsuitable for uneven spring loads such as those used in electromagnetic contactors used on boats.

Furthermore, the monostable electromagnet of Utility Model Publication No. 58-10327 has an intermediate characteristic between the non-polar type and the polar type conventional example, that is, it is polar, so it can achieve low power consumption, and unlike the conventional example, it has an asymmetrical property. Since it is a magnetic circuit, it has characteristics suitable for uneven spring loads.

However, since the magnetic flux of the permanent magnet flows in a closed loop on the return side of the armature, the force in the return direction becomes extremely large, and therefore an operating spring is required to bias the armature toward the operating side in alignment with the spring load. It had drawbacks such as:

It is therefore an object of the present invention to provide a polarized monostable electromagnet that can be applied to offset spring loads without the need for actuation springs.

[Means to solve the problem]

A monostable electromagnet according to claim (1) includes a yoke, an armature having a contact/detachment part that can be moved toward and away from the yoke, and a monostable electromagnet that is wound around at least one of the yoke and the armature so that the armature is moved by excitation. The coil to be attracted by the yoke can be applied to a biased spring load without requiring it, and the attraction force characteristic can be easily matched to the spring load.

According to the monostable electromagnet of claim (2), the magnetic flux of the permanent magnet acts on the entire movement range of the contact/separation portion of the armature, so that the attractive force of the armature can be efficiently increased over the entire movement range. I can do it.

〔Example〕

A first embodiment of the present invention will be described based on FIGS. 1 to 3. In other words, this monostable electromagnet has yoke 1
, a coil 2 , an armature 3 , and a permanent magnet 4 .

The yoke 1 is formed by bending a flat plate into a substantially U-shape.

The coil 2 is wound around one piece of the yoke 1. The armature 3 has a pivot portion 5 that is magnetically coupled to the plate end surface of one end portion 6 of the yoke 1, and also has a contact portion 7 that moves toward and away from the plate end surface of the other end portion 8 of the yoke 1 by swinging. The contact/separation portion 7 is attracted to the yoke 1 by the excitation of the coil 2.

When not energized, it returns to the return position by a return spring (not shown) or the like. The pivoting means for the one end portion 6 and the pivoting portion 5 is fixed to at least one of the yoke and the armature in the vicinity of the contact/separation portion of the armature, and the direction of magnetization is substantially parallel to the moving direction of the armature. It is equipped with a permanent magnet.

The monostable electromagnet of claim (2) is characterized in that, in claim (11), the length of the permanent magnet in the magnetization direction is greater than or equal to the movement range of the contact/separation portion.

[Effect]

According to the monostable electromagnet of claim (1), when the coil is excited, the contact/separation portion of the armature operates so as to be attracted to the yoke. In this case, the magnetic flux generated by the excitation of the coil can form a closed magnetic path by the yoke and armature without including a permanent magnet. Furthermore, since the magnetic flux generated by the permanent magnet can be superimposed on the magnetic flux generated by the coil, the attractive force of the armature can be increased, and power consumption can therefore be reduced. On the other hand, at the return position of the armature, the magnetic flux of the permanent magnet hardly acts in the return direction, so a conventional operating spring is necessarily used.

The permanent magnet 4 is fixed to the other end 8 of the yoke 1 and
is located near. That is, a pair of permanent magnets 4 are used as an example, and magnetic poles S are magnetically coupled and fixed to both ends of an auxiliary yoke 9, and a hole 10 is formed in the center of the yoke 1.
The other end 8 is fitted. Further, the magnetization direction of the permanent magnet 4 is substantially parallel to the movement direction of the contact/separation part 7, and the length of the permanent magnet 4 in the magnetization direction is longer than the movement range of the contact/separation part 7.

According to this embodiment, as shown in FIG. 3 ta+, in the return state of the electromagnet, the magnetic flux Φ1 flows through the armature 3, the yoke l, and the auxiliary yoke 9 due to the magnetizing force of the permanent magnet 4, but the magnetic flux Φ1 flows through the magnetic circuit. Since this is a rough connection, the force that attracts the armature 3 in the return direction hardly acts. On the other hand, a part of the magnetic flux Φ2 flows through the armature 3 and the auxiliary yoke 9, but this magnetic flux Φ2 is a magnetic flux that passes through the armature 3 almost perpendicularly, and the magnetic circuit is also a coarse coupling, so the armature 3 is Almost no suction force acts in the return direction. Therefore, since almost no force is applied to attract the armature 3 in the return direction, it is possible to apply a biased spring load without requiring a conventional operating spring.

Next, when the coil 2 is energized, the armature 3 operates around the pivot portion 5 of the armature 3 so that the contact/separation portion 7 is attracted to the other end portion 8 of the yoke 1. As shown in FIG. 3(b), the magnetic flux Φ3 generated by excitation of the coil 2 is configured to flow in the opposite direction to the aforementioned magnetic flux Φ1,
Yoke 1 and armature 3 without permanent magnet 4
The magnetic flux Φ2 generated by the permanent magnet 4 and the magnetic flux Φ3 generated by excitation of the coil 2 flow through a closed magnetic path due to the magnetic flux Φ2 generated by the permanent magnet 4.
It will be superimposed on Therefore, as the magnetomotive force of the coil 2 increases, the attractive force generated between the yoke 1 and the armature 3 increases, and the magnetic flux Φ2 of the permanent magnet 4 can increase the attractive force toward the operating side of the armature 3. 2. Power consumption can be reduced.

Moreover, although the permanent magnet 4 is magnetically coupled to the yoke 1 in this embodiment, the opposite magnetic pole N may be magnetically coupled. Furthermore, the permanent magnet 4 was fixed directly to the yoke 1, but the yoke 1
case to hold the coil, coil frame for winding coil 2, etc. (
(not shown). Further, the permanent magnet 4 may be a ferrite magnet, a rare earth magnet, or even a plastic magnet. Furthermore, in the embodiment described above, the magnetization direction of the permanent magnet 4 was completely parallel to the moving direction of the armature.
Even if it is tilted by about 45 degrees, it remains approximately parallel.

A second embodiment of the invention is shown in FIGS. 4 and 5.

That is, this monostable electromagnet has a permanent magnet 4 fixed to the armature 3 side, a lug 12 is integrally formed on the armature 3, and a permanent magnet 4 is attached to the lug 12 (
It's 1 digit. The rest is the same as the first embodiment.

By fixing the permanent magnet 4 to the armature 3 side, the weight of the movable part increases, but by manufacturing it by simultaneous molding with the armature 3, the number of parts can be reduced and assembly efficiency can be improved.

By attaching it to the other end 8, the magnetic flux obtained from the permanent magnet 4 can be increased and the attractive force can be increased, so that power consumption can be further reduced.

In addition, since the length of the permanent magnet 4 in the magnetization direction is greater than the movement range of the contact/separation portion 7 of the armature 3, the armature 3
Since the magnetic flux Φ2 of the permanent magnet 4 acts on the entire movement range of the contact/separation part 7, the attractive force of the armature 3 can be efficiently increased and power consumption can be reduced.

Next, when the current flowing through the coil 2 is cut off, the armature 3 returns to the state shown in FIG. 3(a) by a return spring (not shown) or the like.

The yoke 1 was formed by bending one component into a substantially U-shape, but the L-shaped yoke and the rod-shaped or plate-shaped yoke
It may be formed into a substantially U-shaped bent shape by caulking or the like. Further, the auxiliary yoke 9 that contacts one pole of the permanent magnet 4 may be formed integrally with the yoke 1 instead of being a separate member. Furthermore, although the permanent magnet 4 is a pair in the above embodiment, it may be one.

Furthermore, the magnetic pole S of the permanent magnet 4 is connected to the other end 8 of the yoke 1.
A separate member may be used for the ear piece 12. Further, although the permanent magnet 4 is directly fixed to the armature 3, a separate member that operates simultaneously with the armature 3 may be used.

A third embodiment of the invention is shown in FIGS. 6 and 7.

That is, in this monostable electromagnet, the yoke 1 is formed by punching a flat plate into a substantially U-shape, with the armature 3 of the flat plate facing the plate surface, and one permanent magnet 4 attached to the other end 8 of the yoke 1. It is fixed to . The rest is the same as the first embodiment.

According to this embodiment, the electromagnet can be made thinner than the first embodiment.

A fourth embodiment of the invention is shown in FIGS. 8 and 9.

That is, in this monostable electromagnet, the permanent magnet 4 is fixed to the contact/separation part 7 side of the intermediate part of the armature 3 in the third embodiment.

A fifth embodiment of the invention is shown in FIGS. 10 and 11. That is, in this monostable electromagnet, the flat yoke 1 of the third embodiment is formed into a substantially Y-shape instead of the substantially U-shape, and the coil 2 is wound around the intermediate piece 11.

According to this embodiment, compared to the third embodiment, there are two gaps where the suction force acts, so a large suction force can be obtained.

A sixth embodiment of the invention is shown in FIGS. 12 and 13. That is, this monostable electromagnet is the same as the fourth embodiment in which the yoke 1 is formed in a substantially Y-shape instead of the substantially U-shape, and the coil 2 is wound around the intermediate piece 11. It has the same effect as the example.

A seventh embodiment of the invention is shown in FIGS. 14 and 15. That is, in this monostable electromagnet, the yoke 1 has a first magnetic pole part 6' and a second magnetic pole part 8', and the sliding part 5' of the armature 3 has a first magnetic pole part 6' of the yoke 1. The armature 3 is operated so that the detachable part 7 of the armature 3 is attracted to the second magnetic pole part 8' by sliding the magnetic pole part 8'.

The yoke 1 has a substantially square shape as an embodiment, and has a cylindrical first magnetic pole part 6' formed on one of the facing parts, and the other gusset air 3 is operated, so that it is different from the first embodiment. The moving range of the bare gusset air 3 can be increased, and a suction force suitable for a large electromagnetic contact portion can be obtained.

Note that although the yoke l is made of one component approximately in the shape of an opening, it may also be constructed by combining two U-shaped yokes. Further, another member may be interposed between the yoke 1 and the one pole of the permanent magnet 4.

An eighth embodiment of the invention is shown in FIGS. 16 and 17. That is, this monostable electromagnet has a permanent magnet 4 directly fixed to the side of the contact/separation part 7 of the armature 3. The rest is the same as the seventh embodiment.

In addition, in this invention, the coil 2 and the permanent magnet 4 may be provided in both the yoke 1 and the armature 3.

〔Effect of the invention〕

In the monostable electromagnet of claim 11, a permanent magnet whose magnetization direction is approximately parallel to the moving direction of the approaching and separating parts of the armature is arranged near the moving parts of the armature, so that the magnetic flux due to excitation of the coil is
A permanent magnet is not included, and the edge of the yoke hole is used as a second magnetic pole part 8'. The coil 2 is wound around an armature 3, and the armature 3 is configured to pass through the coil 2 so as to be movable in the axial direction. That is, the armature 3 has a sliding part 5' at one end that is magnetically coupled to the first magnetic pole part 6' of the yoke 1, and a contact part 7 that moves toward and away from the second magnetic pole part 8' of the yoke 1 as it moves. It is a roughly rod-shaped body with a . Then, the contact/separation part 7 is attracted to the second magnetic pole part 8' by the excitation of the coil 2. When it is not energized, it returns to the return position by a return spring (not shown) or the like. In addition,
As the means for supporting the sliding portion 5 of the armature 3, a known means is applied.

The permanent magnet 4 is fixed near the second magnetic pole portion 8' of the yoke 1.

The rest is the same as the first embodiment.

According to this embodiment, the yoke 1 has the first magnetic pole part 6' and the second magnetic pole part 8', and the sliding part 5 of the armature 3
A closed magnetic path can be formed by A2 and the armature such that A2 and the armature slide on the first magnetic pole part 6' of the yoke 1 and are attracted to the second magnetic pole part 8'. Furthermore, since the magnetic flux generated by the permanent magnet can be superimposed on the magnetic flux generated by the coil, the attractive force of the armature can be increased, and power consumption can therefore be reduced.

On the other hand, at the return position of the armature, the magnetic flux of the permanent magnet hardly acts in the return direction, so it can be applied to uneven spring loads such as electromagnetic contactors without the need for a conventional operating spring, and it can be matched with the spring load. This has the effect of providing easy suction power characteristics.

In the monostable electromagnet of claim (2), since the length of the permanent magnet in the magnetization direction is longer than the movement range of the armature's contact/separation part, the magnetic flux of the permanent magnet acts on the entire movement range of the armature's contact/separation part. Therefore, the suction force of the armature can be efficiently increased throughout the movement range.

[BRIEF DESCRIPTION OF THE DRAWINGS] Fig. 1 is a perspective view of the first embodiment of the present invention, Fig. 2 is an exploded perspective view thereof, Fig. 3 is an explanatory diagram of the operating state, and Fig. 4 is the second embodiment. A perspective view of an example, FIG. 5 is an explanatory diagram of its operating state,
Fig. 6 is a perspective view of the third embodiment, Fig. 7 is an explanatory diagram of its operating state, Fig. 8 is a perspective view of the fourth embodiment, Fig. 9 is an explanatory diagram of its operating state, and Fig. 10 is an explanatory diagram of its operating state. 11 is a perspective view of the fifth embodiment, FIG. 11 is an explanatory diagram of its operating state, FIG. 12 is a perspective view of the sixth embodiment, FIG. 13 is an explanatory diagram of its operating state, and FIG. 14 is an explanatory diagram of its operating state. A perspective view of the seventh embodiment, FIG. 15 is an explanatory diagram of its operating state, FIG. 16 is a perspective view of the eighth embodiment, and FIG.
The figure is an explanatory diagram of its operating state. DESCRIPTION OF SYMBOLS 1... Yoke, 2... Coil, 3... Armature, 4... Permanent magnet, 7... Approach/separation part 5 U] Fig. 11 (a) (b) Fig. 13 (a ) (b) Figure 15 Figure 17 (b)

Claims (2)

[Claims] (1) a yoke, an armature having a contact portion that can move toward and away from the yoke, and a coil wound around at least one of the yoke and the armature to attract the armature to the yoke through excitation; A monostable electromagnet comprising: a permanent magnet fixed to at least one of the yoke and the armature near a contact/separation portion of the armature, and whose magnetization direction is substantially parallel to a moving direction of the armature. (2) The monostable electromagnet according to claim 1, wherein the length of the permanent magnet in the magnetization direction is longer than the moving range of the contact/separation portion.