JPH0356017Y2 - - Google Patents

Description

[Detailed explanation of the invention] (a) Industrial application field This invention relates to a self-holding type electromagnet that utilizes the magnetic force of a permanent magnet.

(b) Conventional technology Conventionally, in the self-holding electromagnet using the above-mentioned permanent magnet, as shown in Fig. 6, many pairs of identically shaped yokes are placed around a cylindrical bobbin, and the opposite outer end surfaces of the yokes are Permanent magnets are arranged, the outside of each of the permanent magnets is held between yokes A, and yoke B is fixed to the open end of yoke A to form a part of a magnetic circuit. Permanent magnets were fixed with adhesive or covered with covers to prevent the yoke group and permanent magnets from wobbling or falling off.

(c) The problem that the idea aims to solve Conventional technology had many problems.

The first point is that there is a large variation in the size of the permanent magnets, and even if you try to sandwich the permanent magnet and yoke with yoke A, there may be a hole in the clamping direction, or the permanent magnet is too large and yoke A and yoke B The magnetic force of the permanent magnet could not be used effectively because the magnets were not in close contact with each other.

The second point is that, as in the first point, there is a risk that the permanent magnet or yoke may become loose or fall off, so the bobbin and the yoke, the yoke and the permanent magnet, and the permanent magnet and the yoke A. Each can be fixed with adhesive, or with a permanent magnet.
A cover was attached that covered the yoke from the outside to prevent the permanent magnet and yoke from falling off.

The third point is that in order to effectively utilize the magnetic force of a permanent magnet, the yoke must be in contact with the magnetized surface of the permanent magnet in the same size area, but with conventional yoke technology, The thickness of the yoke is thin, and the area facing the magnetized surface of the pair of yokes is extremely small, and the areas facing the magnetized surface are made approximately equal by stacking a plurality of yokes.

The reason why multiple yokes were used was because electromagnets of this type were usually formed by press working in order to provide them at low cost, and it was extremely difficult to precisely punch out very thick plates.

The fourth point is that since multiple pairs of yokes are used, the weight is very large, making it difficult to meet recent demands for weight reduction.

The fifth point is that because of the problematic configuration described in points 1 to 4, only extremely expensive self-holding electromagnets could be provided. The present invention has been made to solve many of the above-mentioned problems all at once.

(d) Means and Examples for Solving Problems The self-holding electromagnet according to the present invention will be explained below based on the drawings.

In FIG. 1, the upper part has a part 7 for storing the permanent magnet 4 and the yoke 3, that is, the part 7 sandwiched between the flanges 1a and 1b, and the lower part has a part 8 for winding the excitation coil 2. That is, flange 1
A yoke 3 and a permanent magnet 4 are attached to a cylindrical bobbin 1 having a portion 8 sandwiched between a flange 1c and a flange 1c.
Insert using a′ as a guide.

The yoke 3 is formed by bending a plate-shaped magnetic material plate as shown in FIGS. 1 to 3 and 5. To explain the shape in detail, the substantially central portion of the magnetic material plate in the longitudinal direction is formed into a semicircle so that the pair of yokes substantially surround the cylindrical bobbin. A plane portion 3a is extended from each end of the semicircle to the left and right so that a pair of opposing yokes come into surface contact. On the other hand, a tip portion 3c is provided beyond the flat portion 3a through the connecting portion 3b, and is in contact with the permanent magnet 4 and whose tips face each other. I have it.

When manufacturing the above-mentioned yoke 3, it is made with the dimension L shown in FIG.

The dimension L is determined by arranging the yoke 3 on both sides of the bobbin 1 with the bobbin 1 at the center as shown in Fig. 3, with the permanent magnets 4 arranged on the outside of the yoke 3, and the yoke A5 mounted on the outside of the yoke 3. Make sure that the size is B in Figure 4.

With the dimension B above, it cannot be said that yoke A5 and yoke B6 are in good contact with each other, and the magnetic loss is large when configuring the magnetic circuit, so yoke A5 and yoke B6 are finally fixed by caulking etc. At this time, the yoke A5 is pressed from the outside surface, and the yoke 3 is elastically deformed to a dimension l such that the yoke A5 has a dimension B' as shown in FIG. 4, and is fixed. FIGS. 8 and 9 show another embodiment of the present invention, which has the same effect as the previous embodiment.

The present invention solves the above problems at once through the above-mentioned means.

(E) Function and effect of the present invention In the self-holding electromagnet according to the present invention as detailed above, only one pair of yoke 3 is sufficient. In addition, the plate thickness of the yoke is made so that the magnetic flux required by the electromagnet can pass therethrough, and the tip 3c of the yoke is shaped like a figure eight, and a pair of yokes and a pair of permanent magnets are incorporated around the bobbin. When clamped by yoke A5, the outer dimension of yoke A5 becomes B, but when fixing yoke A5 and yoke B6, press yoke A5 from the outside so that B becomes B', and then tighten by crimping etc. Since the yoke is fixed, the figure-eight portion of the yoke that makes up the surface that comes into contact with the permanent magnet is elastically deformed, and even if there is some variation in the thickness of the permanent magnet, the yoke can be fixed between the yoke and the permanent magnet, or between the permanent magnet and the yoke A5. Not only can magnetic force be effectively used by eliminating air gaps, but also there is no play in the yoke or permanent magnet.

Further, since the flange 1a of the bobbin is provided with a protruding strip 1a', even if the permanent magnet tries to move sideways, accidents such as falling off can be completely prevented.

In addition, with conventional technology, multiple yokes were required, resulting in a large number of parts and the time and effort required to assemble each one of them, but with the present invention, only a pair of yokes were required, greatly reducing assembly effort. .

If you consider a group of yokes using conventional technology, they are almost solid blocks and are heavy, but the yoke of this invention is almost hollow, which can reduce the weight, and it is the same as a solid yoke while being lightweight. effect can be obtained.

In addition to the above effects, the number of parts is extremely small,
Since the assembly effort can be greatly reduced, the manufacturing cost can also be greatly reduced, and the product can be provided at a low price.This has extremely great effects, and it solves the above-mentioned problems all at once.

[Brief explanation of the drawing]

FIG. 1: An exploded perspective view of an embodiment of a self-holding electromagnet according to the present invention. FIG. 2: A vertical sectional view of an embodiment of the self-holding electromagnet according to the present invention. FIG. 3: A cross-sectional view taken along line E in FIG. 2. FIG. 4: A top view illustrating the relationship between yoke A and yoke B according to the present invention. Fig. 5: An explanatory diagram of the yoke according to the present invention. FIG. 6: An exploded perspective view of a conventional self-holding electromagnet. FIG. 7: Perspective views of two other types of conventional self-holding electromagnet yokes. FIGS. 8 and 9 are sectional views of main parts of other embodiments of the present invention. In the figure, 1, 11... Bobbin, 2, 12... Excitation coil, 3, 13... Yoke, 3a... Flat part, 3
b... Connecting portion, 3c... Tip, 4, 14... Permanent magnet, 5, 15... Yoke A, 6, 16... Yoke B, 1a, 1b, 1c... Flange, 1a'...
...Convex stripes.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A bobbin with an excitation coil wound on one side and a yoke and a permanent magnet inserted on the other side, and a substantially U-shaped bobbin with a fixed iron core arranged and fixed inside the bobbin. A self-holding type with a yoke A, a yoke B that holds the bobbin in place at the open end of the yoke A, and a movable iron core that freely slides inside the bobbin and provides mechanical energy to other equipment. In an electromagnet, the yoke is formed by bending a plate-shaped magnetic material plate, and the approximately center portion of the magnetic material plate in the longitudinal direction is formed along the outer circumferential shape of the bobbin, and the yoke is formed near both longitudinal ends of the magnetic material plate. Formed to be in contact with the magnet and have elasticity,
A pair of yokes and a pair of permanent magnets are sequentially inserted into the bobbin from the bobbin side, and after the outside of the yoke is sandwiched between the yoke A, the yoke A is pressed from the outside to increase the elasticity of the yoke. A self-holding electromagnet characterized in that a yoke B is fixed while elastically deforming both ends, and at least the yoke and the permanent magnet and the permanent magnet and the yoke A are in pressure contact. (2) Of the two flanges provided on the bobbin for inserting the yoke and permanent magnet, at least one flange is equipped with a flange for guiding when inserting the yoke and permanent magnet and to prevent it from falling off. The self-holding electromagnet according to claim 1, wherein the flange is provided with a convex shape toward the yoke or the permanent magnet at two locations on opposing outer ends thereof.