JPH0834150B2 - Monostable electromagnet - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a monostable electromagnet applied to an electromagnetic contactor for opening and closing a three-phase motor.

[Conventional technology]

As a conventional monostable electromagnet of this type, a so-called non-polar electromagnet having no permanent magnet in a magnetic circuit, such as a clapper type electromagnet and an E type electromagnet, has been generally used. Although this non-polar type electromagnet is low in cost, since only the magnetic flux generated by the coil can be used for the driving force of the armature, it was necessary to increase the power consumption in order to obtain a certain attractive force width.

On the other hand, in recent years, a polar type electromagnet device including a permanent magnet in a magnetic circuit has been proposed in order to reduce the power consumption of the electromagnet (for example, Japanese Patent Publication No. 62-17333 and Japanese Utility Model Publication No. 58-10327).
issue).

[Problems to be Solved by the Invention]

However, in the monostable electromagnet of Japanese Patent Publication No. Sho 62-17333, since the magnetic flux of the permanent magnet can also be used for the driving force of the armature, it is possible to reduce the power consumption compared with the non-polar type in order to obtain a certain attractive force width. However, since it is an electromagnet structure for bistable, it is not suitable for a biased spring load of a general electromagnetic contactor.

On the other hand, the monostable electromagnet of Japanese Utility Model Publication No. 58-10327 has an intermediate characteristic between the non-polar type and the polar type of the conventional example, that is, it has low power consumption because it is polar. Unlike the asymmetric magnetic circuit, it has characteristics suitable for biased spring load.

However, since the U-shaped yoke has a punched structure and the plate-shaped armature is parallel to the coil axis direction, it is not suitable as an electromagnet for a thin cubic electromagnetic contactor because a coil space cannot be secured.

Therefore, an object of the present invention is to provide a thin cubic electromagnet without reducing the coil space, and also to provide a monostable electromagnet capable of increasing the attractive force of the armature and further reducing power consumption. That is.

[Means for solving the problem]

The monostable electromagnet according to claim (1) has a first yoke, a coil wound around the first yoke, and a base end portion that is magnetically coupled to one end of the first yoke. An armature having a free end portion that comes into contact with and separates from the other end of the first yoke, a permanent magnet that is disposed at the other end of the first yoke and has one pole magnetically coupled to the other end, and the other pole of the permanent magnet. A second yoke that is magnetically coupled to the first yoke and attracts the free end portion of the armature that is separated from the other end of the first yoke in a non-excited state.

The monostable electromagnet according to claim (2) further comprises an operation spring for urging the armature toward the first yoke.

[Action]

According to the monostable electromagnet of claim (1), when the coil is excited, the armature operates so that the free end of the armature is attracted to the other end of the first yoke, and when the excitation is released, the armature returns. Adsorb to the second yoke. In this case, since the armature is perpendicular to the coil axis direction, when it is applied to a thin cubic electromagnet, the coil, the first yoke, the second yoke and the permanent magnet have a large space.
These spaces can be effectively used. Further, since the permanent magnet is not included when the coil is excited, a closed magnetic circuit can be formed by the first yoke and the armature, so that the attractive force of the armature can be increased and the power consumption can be further reduced.

According to the monostable electromagnet of claim (2), the action spring for biasing the armature toward the first yoke assists the attraction force to the action side of the armature due to the excitation of the coil to increase the action force. Since the base end portion of the armature is also urged toward the first yoke side, the fulcrum of the base end portion can be stably supported, the operation can be smoothed, and the life can be extended.

〔Example〕

A first embodiment of the present invention will be described with reference to FIGS. That is, this monostable electromagnet has a first yoke 1, a coil 2, an armature 3, a permanent magnet 4, and a second yoke 5.

 The first yoke 1 has a substantially U-shape as an example.

 The coil 2 is wound around the first yoke 1.

The armature 3 has a base end portion 7 that is magnetically coupled to one end 6 of the first yoke 1 and a free end portion 8 that contacts and separates from the other end 9 of the first yoke 1. And the free end 8
Is located between the other end 9 of the first yoke 1 and the second yoke 5, and is attracted to the second yoke 5 during non-excitation.
Is attracted to the first yoke 1 by the excitation.

The permanent magnet 4 is arranged at the other end 9 of the first yoke 1 and has one pole magnetically coupled to the other end 9. A pair of permanent magnets 4 is used as an example, and a hole 11 is formed in the central portion of the third yoke 10 and fitted in the other end 9 of the first yoke 1.

The second yoke 5 is magnetically coupled to the other pole of the permanent magnet 4 and attracts the free end portion 8 of the armature 3 separated from the other end 9 of the first yoke 1 in a non-excited state. In the embodiment, the second yoke 5 is arranged in parallel with the third yoke 10 and both ends thereof are fixed to the magnetic pole N of the permanent magnet 4.

Further, this embodiment is provided with an operating spring 12 for urging the armature 3 toward the first yoke 1 side (operating side) at approximately the center between the one end 6 and the other end 9 of the first yoke 1. 13 is a spring receiving portion.

Since this monostable electromagnet has a large attraction force in the return operation direction in the non-excited state, it returns against the operation spring 12 without a return spring (not shown) as a separate member.

According to this embodiment, the armature 3 operates so that the free end 8 of the armature 3 is attracted to the other end 9 of the first yoke 1 when the coil 2 is excited, and the armature 3 returns when the excitation is released. And is attracted to the second yoke 5. In this case, since the armature 3 is perpendicular to the coil axis direction, when it is applied to a thin cubic electromagnet, the coil 2, the first yoke 1, the second yoke 5 and the permanent magnet 4 have a large space. Can be effectively used. Further, since the closed magnetic circuit can be formed by the first yoke 1 and the armature 3 without including the permanent magnet 4 when the coil 2 is excited, the power consumption that can increase the attraction force of the armature 3 can be further reduced. .

Further, the operating spring 12 assists the attraction force acting on the operating side of the monostable electromagnet to increase the operating force, and the base end portion 7 of the armature 3 is pressed against the one end 6 of the first yoke 1, so that the armature 3 The fulcrum of the rotating operation is supported stably, the operation is smoothed, and the life can be extended.

Further, in this embodiment, a magnetic plate material is punched into a predetermined shape and bent into a U-shape to form a first yoke 1, a coil 2 is wound, and a plate-shaped armature 3 is erected so as to stand up. The base end portion 3 of 3 is made to face one end 6 of the first yoke 1, and the free end portion 8 is made to face the other end 9,
The coil 2 can be efficiently wound.

A second embodiment of the present invention is shown in FIG. That is,
In this monostable electromagnet, the second yoke 5 is bent in a U shape, and the magnetic pole N of the permanent magnet 4 is attached to the inside of both end pieces thereof.
The magnetic pole S of the permanent magnet 4 is provided on the side portion on the first yoke 1 side, and the third yoke 10 is omitted.

In the case of this embodiment, the number of parts is smaller than that of the first embodiment, and the armature 3 and the second yoke 5 can be made substantially parallel to each other at the non-excitation position of the armature 3, so that no excitation is performed. The magnetic coupling between the two can be improved. Others are the same as those in the first embodiment.

Although the first yoke 1 is a one-piece substantially U-shaped example, it may be a Y-shaped yoke and a bar-shaped or plate-shaped yoke. The operation spring 12 is a coil spring in the embodiment, but may be a leaf spring or the like.
Further, although the permanent magnet 4 is a pair in the above embodiment, it may be one. Further, in the embodiment, the magnetic pole N of the permanent magnet 4 is joined to the second yoke 5, but the opposite magnetic pole S may be joined.

〔The invention's effect〕

The monostable electromagnet according to claim (1) has a large space for the coil, the first yoke, the second yoke and the permanent magnet when applied to a thin cubic electromagnet because the armature is perpendicular to the coil axis direction. These spaces can be effectively used. In addition, since the closed magnetic circuit can be formed by the first yoke and the armature without including the permanent magnet when the coil is excited, the attractive force of the armature can be increased and the power consumption can be further reduced.

The monostable electromagnet according to claim (2) has the armature as the first armature.
In order to increase the operation force by assisting the attraction force to the operation side of the armature due to the excitation of the coil by the operation spring for urging the armature to the yoke side, the base end of the armature is also urged to the first yoke side. The effect is that the fulcrum of the base end is stably supported, the operation is smoothed, and the life is extended.

[Brief description of drawings]

1 is a perspective view of a first embodiment of the present invention, FIG. 2 is an exploded perspective view thereof, FIG. 3 is a plan view in which only a coil portion is sectioned, and FIG. 4 is a perspective view of the second embodiment. Is. 1 ... First yoke, 2 ... Coil, 3 ... Armature, 4 ... Permanent magnet, 5 ... Second yoke, 6 ... One end, 7 ... Base end, 8 ... Free end , 9 ... the other end, 12 ...
... Operating spring

Claims (2)

[Claims] 1. A first yoke, a coil wound around the first yoke, and a base end portion for magnetically coupling to one end of the first yoke, and to the other end of the first yoke. An armature having a free end portion that contacts and separates, a permanent magnet that is disposed at the other end of the first yoke and has one pole magnetically coupled to the other end, and is magnetically coupled to the other pole of the permanent magnet. A monostable electromagnet comprising: a second yoke that attracts the free end of the armature away from the other end of the first yoke in an excited state. 2. The monostable electromagnet according to claim 1, further comprising an operating spring for urging the armature toward the first yoke.