JPH03196506A - Monostable electromagnet - Google Patents

Abstract

PURPOSE:To apply a monostable electromagnet to deviated spring load without requiring a working spring by installing a permanent magnet, which is arranged near the contacting and separating section of an armature and the direction of magnetization of which is approximately perpendicular to the direction of movement of the armature. CONSTITUTION:Permanent magnets 4 are fixed to another end section of a yoke 1 and arranged near a contacting and separating section 7, magnetic poles S are magnetically coupled with the inner side faces of both end sections of an approximately U-shaped auxiliary yoke 9, the direction of magnetization is made approximately perpendicular to the direction of movement of the contacting and separating section 7, and the magnetic poles N of the permanent magnets 4 are faced oppositely to the side sections of an armature 3. Consequently, magnetic flux PHI1 flows through the armature 3, the yoke 1 and the auxiliary yoke 9 by the magnetizing force of the permanent magnets 4, and force attracting the armature 3 in the return direction hardly works. When magnetic flux PHI2 is made to overlap magnetic flux PHI3 generated by exciting a coil 2, attraction force to the operation side of the armature 3 is increased, thus reducing the power consumption of the coil 2. Accordingly, a monostable electromagnet can be applied to deviated spring load without requiring a working spring.

Description

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

[Conventional technology]

Conventionally, as monostable electromagnets of this type, so-called non-polar electromagnets that do not include a permanent magnet in their magnetic circuits, such as clapper-type electromagnets, have been common. 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.

In response to this, in recent years, breeding electromagnet devices that include permanent magnets in the magnetic circuit have been devised in order to reduce the power consumption of electromagnets (for example, Japanese Patent Publication No. 62-17333, Utility Model Publication No.
No. 10327).

[Problem to be solved by the invention]

The monostable TM stone disclosed in Japanese Patent Publication No. 62-17333 can also 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 some shortcomings, such as:

It is therefore an object of this 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]

The monostable electromagnet of claims 1 and 1 includes a yoke, an armature having a contact/separation portion capable of contacting/separating movement along the yoke, and a monostable electromagnet wound around at least one of the yoke and the armature and being excited by excitation. The magnet includes a coil that attracts the armature to the yoke, and a permanent magnet that is disposed near the contact/separation portion of the armature and whose magnetization direction is substantially perpendicular to the direction of movement of the armature.

In the monostable electromagnet of claim (2), in claim fi+, the permanent magnet is fixed to at least one of the armature and the yoke, and the moving direction of the contacting and separating portion of the magnetic pole of the permanent magnet facing the other one is provided. The length in the same direction as
This is set to be greater than the movement range of the contact/separation portion.

The monostable electromagnet according to claim 3) is the monostable electromagnet according to claim 11, wherein the permanent magnet is provided with a magnetic flux collecting plate on its magnetic pole.

[Effect]

Monostable in claim fil! According to the magnet, 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 does not form a closed loop, and almost no magnetic flux of the permanent magnet acts in the direction of return of the armature. It can be applied to the load and provides suction force characteristics that are easily matched to the spring load.

According to the monostable electromagnet of claim (2), the length of the magnetic pole of the permanent magnet of claim il+ in the same direction as the moving direction of the contact/separation portion is set to be greater than or equal to the movement range of the contact/separation portion. Since the magnetic flux of the permanent magnet acts on the entire movement range of the approaching/separating portion, together with the effect of claim 11, the attractive force of the armature can be efficiently increased over the entire movement range.

According to the monostable electromagnet of claim (3), since the permanent magnet is provided with a magnetic flux collecting plate on the magnetic pole, the magnetic flux generated by the permanent magnet can be collected without leaking into the armature or the yoke, so that the efficiency is further improved. This improves the attractive force of the armature when the coil is excited.

〔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 wrapped around a piece of yoke. 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. Note that a known hinge means is used as the pivot means for the one end portion 6 and the pivot portion 5.

The permanent magnet 4 is fixed to the other end 8 of the yoke l, and the contact/separation part 7
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 the inner surfaces of both ends of a substantially U-shaped auxiliary yoke 9, and a hole IO is formed in the center.
is formed and fitted onto the other end portion 8 of the yoke 1. Further, the magnetization direction of the permanent magnet 4 is almost perpendicular to the moving direction of the contact/separation part 7, and the magnetic pole N of the permanent magnet 4 faces the side part of the armature 3, and the magnetic pole N is in the same direction as the movement direction of the contact/separation part 7. The length in the direction is longer than the movement range of the contact/separation part 7.

According to this embodiment, as shown in FIG. 3 fat, in the return state of the electromagnet, the magnetic flux Φ1 flows through the armature 3, the yoke 1, and the auxiliary yoke 9 due to the magnetizing force of the permanent magnet 4, but the magnetic flux Φ1 Since these are mutually coupled, 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 loosely coupled, so the armature 3 is Almost no force to attract the armature 3 in the return direction acts, therefore, almost no force acts to attract the armature 3 in the return direction.
Does not require a conventional operating spring (applicable to biased spring loads).

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 l. As shown in FIG. 3 tb+, the magnetic flux Φ3 generated by the 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.
Power consumption of the coil 2 can be reduced.

In addition, since the length of the magnetic pole 4 of the permanent magnet is set to be longer than the moving range of the contacting and separating part 7 of the armature 3, the magnetic flux Φ2 of the permanent magnet 4 acts on the entire moving range of the contacting and separating part 7 of the armature 3, which improves efficiency. Therefore, the suction force of the armature 3 can be increased, and power consumption can be reduced.

Furthermore, by attaching the permanent magnet 4 to the other end 8 of the yoke l, the magnetic flux obtained from the permanent magnet 4 increases, thereby increasing the attractive force, thereby further reducing power consumption.

Next, when the current flowing through the coil 2 is cut off, the armature 3 returns to the state shown in FIG. 3 ta+ 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 l instead of being a separate member. Furthermore, although the permanent magnet 4 is a pair in the above embodiment, it may be one.

Further, although the magnetic pole S of the permanent magnet 4 is magnetically coupled to the other end portion 8 of the yoke 1, the opposite magnetic pole N may be magnetically coupled.

Furthermore, although the permanent magnet 4 is fixed to the yoke 1, it may be fixed via a case that holds the yoke 1, a coil frame around which the coil 2 is wound, or the like (not shown). Further, the permanent magnet 4 may be a ferrite magnet, a rare earth magnet, or even a plastic magnet.

Further, in the embodiment described above, the magnetization direction of the permanent magnet 4 was completely perpendicular to the direction of movement of the armature, but even if it is tilted by about 45 degrees, it remains almost perpendicular.

Further, in the embodiment, the magnetic flux Φ3 flows in the opposite direction to the magnetic flux Φ1, but the magnetic flux Φ3 may flow in the same direction as the magnetic flux Φ1.

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

That is, in this monostable electromagnet, a permanent magnet 4 is fixed to a connecting/separating part 7 on the armature 3 side, a pair of hook-shaped ears 11 are integrally formed on the armature 3, and the inner side of each ear piece 11 is formed integrally with the armature 3. A permanent magnet 4 is attached to the yoke 1, and the magnetic pole S faces the side surface of the other end 8 of the yoke 1. 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.

Note that a separate member may be used for the lug 11, and although the permanent magnet 4 is directly fixed to the armature 3,
It is also possible to use a separate member that operates at the same time.

A third embodiment of the invention is shown in FIGS. 6 to 8.

That is, this monostable electromagnet is the same as the first embodiment in which a magnetic flux collecting plate 12 is provided at the magnetic pole N of the permanent magnet 4.

According to this embodiment, the magnetic flux Φ1°Φ2 leaks (flows) from the permanent magnet 4 to the armature 3 through the magnetic flux collecting plate 12, so that efficiency can be improved.

Therefore, on the return side of the armature 3, the magnetic circuit is loosely coupled as shown in Figure 3 (body 3), so the force that attracts the armature 3 in the return direction hardly acts. armature 3 is yoke l
Since it becomes a closed magnetic path when approaching , it can contribute to increasing the attraction force of the armature 3, and the attraction force can be increased compared to the first embodiment in which the magnetic collector plate 12 is not provided.

A fourth embodiment of the invention is shown in FIGS. 9 and 10, namely, this monostable! In the second embodiment, the magnet is such that an S magnetic plate 12 is provided on the magnetic pole S of the permanent magnet 4, and the magnetic flux collecting plate I2 allows the magnetic flux to flow between the magnetic pole S and the yoke 1 without leakage. Therefore, there is an effect similar to that of the third 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 full, a permanent magnet whose magnetization direction is almost perpendicular 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 the excitation of the coil is
A closed magnetic path can be formed 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 does not form a closed loop, and almost no magnetic flux of the permanent magnet acts in the direction of return of the armature. This has the effect of providing suction force characteristics that can be applied to loads and easily match spring loads.

In the monostable electromagnet according to claim (2), the length of the magnetic pole of the permanent magnet according to claim 11 in the same direction as the movement direction of the contact/separation portion is set to be greater than or equal to the movement range of the contact/separation portion. Since the magnetic flux of the permanent magnet acts over the entire movement range of the armature, in addition to the effect of claim 1, the attractive force of the armature can be efficiently increased over the entire movement range.

In the monostable magnet according to claim (3), since the permanent magnet is provided with a magnetic flux collecting plate on the magnetic pole, the magnetic flux generated by the permanent magnet can be collected without leaking into the armature or the yoke, so that the efficiency is further improved. This improves the attraction force of the armature when the coil is energized.

[Brief explanation of drawings]

FIG. 1 is a perspective view of the first embodiment of the invention, FIG. 2 is an exploded perspective view thereof, FIG. 3 is an explanatory diagram of the operating state, FIG. 4 is a perspective view of the second embodiment, and FIG. The figure is an explanatory diagram of its operating state,
Fig. 6 is a perspective view of the third embodiment, Fig. 7 is an exploded perspective view thereof, Fig. 8 is an explanatory diagram of the operating state, Fig. 9 is a perspective view of the fourth embodiment, and Fig. 10 is its exploded perspective view. It is an explanatory diagram of an operating state. 1... Yoke, 2... Coil, 3... Armature, 4... Permanent magnet, 7... Approach/separation part 3 Figure (a) (b) 2 Drawing procedure amendment (voluntary 1゜゜゜Cow 1shiR 1999 Patent Application No. 340003 2゜Name of the invention Monostable electromagnet 3゜Relationship with the amended case

Claims (3)

[Claims] (1) a yoke, an armature having a contact portion that can move toward and away from the yoke, and a coil that is wound around at least one of the yoke and the armature and causes the armature to be attracted to the yoke by excitation;
A monostable electromagnet comprising: a permanent magnet disposed near a contact/separation portion of the armature, the magnetization direction of which is substantially perpendicular to the direction of movement of the armature. (2) The permanent magnet is fixed to at least one of the armature and the yoke, and the length of the magnetic pole of the permanent magnet facing the other in the same direction as the moving direction of the contact and separation portion is such that the length of the contact and separation portion is The monostable electromagnet according to claim 1, which has a movement range or more. (3) The monostable electromagnet according to claim (1), wherein the permanent magnet is provided with a magnetic flux collecting plate on its magnetic pole.