JPS6348086Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electromagnet device, and more particularly, to an electromagnet device that moves one of a yoke and an armature by electromagnetic action acting between the two.

This type of electromagnetic device is widely used as an important drive device for controlling operating members of cameras, tape recorders, etc.

Next, an example of a conventional electromagnetic device of this type is shown in the first example.
This will be explained using figures. The electromagnet device described here is called a release type electromagnet device.
This electromagnet device includes a yoke part 1 fixed to a fixed member (not shown), an armature 2 as a movable part that is moved away from the yoke part by electromagnetic force, and an armature support lever 8 that supports the armature 2. There is. In the yoke portion 1, yokes 4 and 5 made of a high magnetic permeability material such as permalloy sandwich a permanent magnet 3, and an excitation coil 6 is wound around one of the two yokes 4 and 5. A bypass member 7 made of a ferromagnetic material with high magnetic resistance, such as iron, is provided as a side magnetic path on one side wall of the permanent magnet 3. Adsorption surface 4 of the above yokes 4 and 5
a and 5a are machined with high surface precision so that when the attracting surface 2a of the armature 2 made of a high magnetic permeability material such as permalloy is attracted, a gap is not formed. The armature 2 is rotatably supported by fitting a circular shaft hole 2b provided approximately in the center onto a support shaft 9 erected on one side of the armature support lever 8. Further, an E-ring 10 is fitted in a circumferential groove 9a of the shaft 9 to prevent the armature 2 from coming off, and a stopper 8a for regulating the position of the armature 2 is provided on the armature support lever 8. A bearing portion 11 is fixedly provided on the other side of the armature support lever 8, and is rotatably fitted onto a shaft (not shown) provided upright on a fixed member. The armature support lever 8 is rotationally biased clockwise by a spring 12 whose one end is fixed to the fixed member.

In the above electromagnet device, when no excitation current flows through the coil 6, as shown in FIG. 2, the magnetic flux of the permanent magnet passes through the bypass member 7 with high magnetic resistance (dashed line in FIG. 2). Since the path of yoke 5 with low magnetic resistance → armature 2 → yoke 4 (solid line in FIG. 2) is easy to pass, attraction magnetic force is generated on the attraction surfaces 4a and 5a of the yokes 4 and 5, and the armature support lever 8 is It is attracted and held by the yokes 4 and 5 with the spring 12 biased. In this state,
When the excitation current flows through the coil 6, a magnetic flux is generated in the coil 6 in a direction that cancels the magnetic flux of the permanent magnet 3. As shown in FIG. The magnetic flux passing through the bypass member (broken line in Figure 3) decreases, and the magnetic flux passing through the bypass member (solid line in Figure 3) increases. Therefore, when the attracting magnetic force of the attracting surfaces 4a and 5a decreases and the biasing force of the spring 12 becomes greater than the attracting magnetic force, the armature support member rotates clockwise as viewed in FIG.

By the way, in the above conventional electromagnet device,
The armature 2 is allowed to swing slightly about the support shaft 9, and the gap between the suction surfaces of the yokes 4 and 5 and the armature 2 is eliminated by the swing of the armature 2. In this case, it is necessary to provide a stopper 8a that limits the rotation range of the armature 2 about the support shaft 9, resulting in a problem that the structure of the electromagnet device becomes complicated.

Furthermore, it is necessary to provide an E-ring on the support shaft 9 to prevent the armature 2 from coming off, which increases the height of the electromagnet, which is an obstacle to miniaturization.

SUMMARY OF THE INVENTION In view of the above-mentioned drawbacks of the conventional electromagnetic device, it is an object of the present invention to provide an electromagnet device that has a simple structure, can be made compact, and does not create a gap between the attracting surfaces of the yoke and the armature.

The present invention will be explained below using an illustrated embodiment.

The yoke portion 1 includes a permanent magnet 3, a pair of yokes 4 and 5 that sandwich the magnet, a coil 6 wound around one of the yokes 4, and a bypass member 7 provided on the side wall of the permanent magnet 3. These are the same as conventional electromagnetic devices. An elliptical shaft hole 2c is provided approximately in the center of the armature 2, which serves as a movable part that is attracted to the attraction surfaces 4a, 5a of the yokes 4, 5. On one side of the armature support lever 13 that supports the armature 2 as the movable part, an armature support shaft 13a that fits into the shaft hole 2c and rotatably holds the armature support lever 13 is formed by cutting a part of the support lever 13 into a square shape. It is formed into a column. On the other hand, a bearing portion 13b is provided on the other side of the support lever 13, and is fitted onto a shaft provided upright on a fixed member to rotatably support the lever 13. Here, as shown in FIG. 6, the shaft hole 2c of the armature 2 has a size sufficient to allow sufficient rotation within the shaft hole. Therefore, the bending accuracy when forming the support shaft 13a may be somewhat poor. Armature 2 and armature support lever 1
3, the bottom surface of the armature 2 and the outer shape are approximately the same, and a rectangular support shaft 13 is provided approximately at the center.
A plastic film sheet 14 is provided which has an opening 14a which can be inserted into the opening 14a. The support shaft 13a and the armature 2 are bonded between the oval shaft hole 2c and the support shaft 13a using a silicone rubber adhesive that hardens over time and has a certain elasticity, or an epoxy resin that hardens over time. It is fixed by injecting a filler.

A method of assembling the armature 2 and the armature support lever 13 of the present invention constructed as described above will be explained. The yoke portion 1 is fixed to a fixing member (not shown), and the armature support lever 13 on which the film sheet 14 and armature 2 are fitted is pivotally supported by a pin (not shown) of the fixing member. In this state, the armature 2 and the yokes 4, 5 are attracted to each other without any positional restrictions, so the attraction surfaces 4a, 5a of the yoke and the attracted surface of the armature 2 are kept in perfect contact. It is held by the armature support lever 13 as it is. Next, with the yokes 4, 5 and the armature 2 still attracted, a filler 15 such as silicone rubber adhesive or epoxy resin is injected between the shaft hole 2c and the support shaft 13a. At this time, the film sheet 14 prevents the filler from flowing out from a small gap between the support shaft 13a and the armature 2, which is formed by cutting and bending a part of the armature support lever 13. By curing the filler, assembly of the electromagnetic device of the present invention is completed.

In the electromagnet device of the present invention, as described above, the armature 2 is attached to the support shaft 1 while being attracted to the yokes 4 and 5.
3a with a filler 15, the parallelism of the suction surfaces of the yokes 4, 5 and the armature 2 can be made highly accurate without adjustment, and the filler also prevents the armature from coming off. Therefore, the height of the electromagnetic device can be lowered compared to when an E-ring is used, and the desired goal can be achieved.

Further, the support shaft 13a has a rectangular cross section and the shaft hole 2c.
Since it has an oval shape, even if the armature 2 is forcibly rotated with respect to the support shaft 13a, the armature 2 is difficult to move, and therefore a stopper is not required. Furthermore, since the cut and bent portion of the armature support lever 13 is used as the armature support shaft, there is an advantage that it is possible to eliminate the trouble of erecting the support shaft 9 on the armature support lever as in the conventional case.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments. For example, the shaft hole 2 provided in the armature 2
The shape of c was an ellipse in the example, but it may also be a shape other than a perfect circle, for example a polygon as shown as 2d in FIG. Any shape is acceptable as long as it generates force.

Further, in one embodiment of the present invention, the side wall of the support shaft 13a was flat, but as shown in FIG. By providing the sag portion 2e that occurs when drilling holes by press working, the adhesion force between the armature 2 and the support shaft 13b is further strengthened, and the armature 2 is more reliably prevented from falling off from the support shaft 13b. can.

Furthermore, although the above embodiments have all been described with reference to the case where the yoke is fixed and the armature is movable, it goes without saying that it can be applied in exactly the same way to an electromagnetic device in which the armature is fixed and the yoke is movable.

Furthermore, although silicone rubber and epoxy resin are used as the filler, it may also be used as a foamable synthetic resin that foams and solidifies over time and has elasticity. In this elastic state,
By integrating the support shaft and the armature, when the armature is attracted to the yoke, the shock between them due to the attraction is absorbed, so the durability of the electromagnet is further improved.

As explained above, the present invention uses a curable filler in an electromagnetic device that moves either a yoke or an armature as a movable part, as a means of connecting this movable part to a support member that supports and moves the movable part. As a result, it is possible to eliminate the drawbacks of conventional electromagnetic devices of this type, and to provide an electromagnetic device that is smaller in size, lower in cost, and has improved durability.

[Brief explanation of the drawing]

Fig. 1 is an exploded perspective view showing a conventional release type electromagnet device, Figs. 2 and 3 are schematic plan views showing the magnetic flux path of the permanent magnet in the yoke and armature, and Fig. 4 is an implementation of the present invention. An exploded perspective view showing an example, FIGS. 5 and 6 are views showing the relationship between the armature and the support shaft in the above embodiment, FIG. 7 is a view showing another embodiment of the present invention, and FIG. 8 is a view showing the present invention. FIG. 7 is a sectional view showing still another embodiment of the invention. 2... Armature, 2c, 2d... Shaft hole, 3
... Permanent magnet, 4, 5 ... Yoke, 6 ... Excitation coil, 13 ... Armature support lever, 13a
... Support shaft, 13b ... Uneven portion, 15 ... Filler.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) In an electromagnetic device in which one of the above two is moved as a movable part by electromagnetic action acting between a yoke and an armature, A movable movable member integrally formed with a shaft hole having a non-perfect circular shape and a support shaft having a non-perfect circular cross section and which is inserted into the shaft hole and rotatably holds the movable part An electromagnet device comprising: a support member; and a curable filler filled between the shaft hole and the support shaft. (2) The electromagnet device according to claim 1, wherein the support shaft has an uneven portion on a side wall. (3) The electromagnet device according to claim 1, wherein the support shaft is formed by cutting and bending a part of the support member.