JPH031156Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a round ring pole type permanent magnet chuck in which a polarity fixed magnet and a polarity changing magnet are arranged concentrically.

[Technical background of the invention and its problems]

In addition to fixed polarity magnets whose direction of magnetization is fixed, permanent magnet chucks are equipped with polarity conversion magnets that can change the direction of magnetization to turn the chuck on and off. It was common to have one placed in the However, these permanent magnets are hard and brittle and difficult to bend, making it difficult to obtain arc-shaped or ring-shaped magnets. Therefore, the pattern of the magnetic pole plates of conventional round permanent magnet chucks has a parallel pattern similar to that of square chucks, as shown in FIG. 5, for example. In addition,
FIG. 5 is a plan view of a conventional device, in which a polarization plate 2 is embedded in a magnetic pole plate 1 in parallel. For this reason, there was a problem in that the structure of the round permanent magnet chuck became complicated and assembly became troublesome.

[Purpose of invention]

This idea was made in view of the above circumstances.
To provide a round ring pole type permanent magnet which has a simple structure and has a ring-shaped magnetic pole plate pattern.

[Summary of the idea]

In order to achieve the above object, the present invention concentrically arranges a fixed polarity magnet with a large coercive force between a magnetic pole plate in which a polarization plate is embedded in a ring shape and a bottom plate, and under this fixed polarity magnet. This product provides a round ring pole type permanent magnet chuck in which ring-shaped polarity conversion magnets with small coercive force are arranged concentrically on the side, and a coil for polarity conversion is wound around each ring-shaped polarity conversion magnet. be. Here, by using a highly flexible ferrite-based or rare earth-based rubber-like plastic magnet as the fixed polarity magnet, a ring-shaped magnet having an arbitrary diameter can be easily formed.

[Example of idea]

Hereinafter, some embodiments of the present invention will be described with reference to FIGS. 1 to 4 of the accompanying drawings. In addition, in the description of the drawings, the same elements are indicated by the same reference numerals.

Fig. 1 is a longitudinal sectional view of one embodiment of the present invention, Fig. 2 is a plan view thereof, and the upper right quarter of Fig. 2 is the first embodiment.
The cross section taken along the line A-A in the figure is shown, and the lower right quadrant shows the cross section taken along the line B-B. Magnetic pole plate 1 made of magnetic material such as soft iron
The peripheral edge of the bottom plate 4 made of a magnetic material and having a U-shaped cross section is joined to the peripheral edge of the bottom plate 4.
A predetermined space is formed between these.
Here, ring-shaped polarization plates (spacers) 2 are concentrically embedded in the upper surface of the magnetic pole plate 1 at appropriate intervals, and serve to guide the lines of magnetic force upward to the magnetic pole plate 1.

A concentric iron core 3 is arranged in the space between the magnetic pole plate 1 and the bottom plate 4 so as to be in contact with the lower surface of the magnetic pole plate 1, and a polarity fixed magnet made of a permanent magnet with a large holding force is installed between the iron cores 3. 5a is embedded.
As this fixed polarity magnet 5a, a highly flexible ferrite-based or rare earth-based rubber-like plastic magnet is used, but these can be easily transformed into a ring shape when formed into a rectangular or band shape during assembly. Therefore, it is easy to embed and fix between the iron cores 3. The fixed polarity magnets 5a are arranged so that the same poles of adjacent magnets face each other.

Next, polarity changing magnets 5b made of permanent magnets with a small coercive force are arranged concentrically on the lower surface of the iron core 3. That is, the polarity changing magnet 5b is provided at a lower portion between the polarity fixed magnets 5a so as to be in contact with the iron core 3, and its magnetic pole faces the iron core 3. As such a polarity changing magnet 5b, for example, an alnico magnet can be used. Then, the coil 6 is wound around the outer peripheral surface of each of the polarity changing magnets 5b to complete the assembly. This coil 6 works to excite the polarity converting magnet 5b and convert the magnetic pole in contact with the lower surface of the iron core 3 and the magnetic pole in contact with the upper surface of the bottom plate 4 from S pole to N pole and from N pole to S pole. .

Next, the operation of the embodiment shown in FIGS. 1 and 2 will be explained.

In FIG. 1, the left half shows the ON state in which the workpiece 7 is attracted, and the right half shows the OFF state in which the workpiece 7 is released.

When the polarity changing magnet 5b is reversely excited by passing a current through the coil 6, the polarity changing magnet 5 facing the fixed polarity magnet 5a as shown in the right half of FIG.
The magnetic pole b is different from the polarity of the fixed polarity magnet.
Therefore, the magnetic circuit does not short-circuit between the fixed polarity magnet 5a, the polarity changing magnet 5b, and the bottom plate 4, and does not appear on the top surface of the magnetic pole plate 1, as in the loop F1. As a result, the workpiece can be released.

On the other hand, when the current passed through the coil 6 is reversed to the above and the polarity changing magnet 5b is positively excited, as shown in the left half of FIG. Fixed polarity magnet 5a
become the same pole as Therefore, the magnetic circuit is vertically guided through the polarity fixing magnet 5a, the polarity changing magnet 5b, and the bottom plate 4 like a loop F2, and is guided to the polarization plate 2 and exits from the top surface of the magnetic pole plate 1. For this reason, it becomes an ON state, and the workpiece 7 is attracted.

4 and 5 are plan views of other embodiments of the present invention, respectively. That is, the pattern of the magnetic pole plate may be an elliptical ring-pole pattern as shown in FIG. 4, or may be a rounded square pattern as shown in FIG. In these cases, the permanent magnet in the chuck has an elliptical ring shape or a rounded rectangular endless shape.

[Effect of idea]

As described above, in the present invention, fixed polarity magnets with a large coercive force are arranged concentrically between a magnetic pole plate in which a polarized plate is embedded in a ring shape and a bottom plate, and a fixed polarity magnet with a large coercive force is placed under the fixed polarity magnet. Small ring-shaped polarity conversion magnets are arranged concentrically, and a coil for polarity conversion is wound around each ring-shaped polarity conversion magnet, so the structure is simple and the pattern of the magnetic pole plate is a ring-shaped round ring. A pole type permanent magnet chuck is obtained. In particular, in the present invention, a highly flexible plastic magnet can be used as the fixed polarity magnet with a large coercive force, so that the fixed polarity magnet can be easily transformed into a ring shape of any diameter.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view showing one embodiment of the present invention, FIG. 2 is a partially cutaway plan view thereof, FIGS. 3 and 4 are plan views of other embodiments of the present invention, and FIG. FIG. 2 is a plan view of an example of a conventional device. 1...Magnetic pole plate, 2...Polarization plate, 3...Iron core, 4
...Bottom plate, 5a...Polarity fixed magnet, 5b...Polarity conversion magnet, 6...Coil.

Claims (1)

[Claims for Utility Model Registration] A magnetic pole plate in which polarization plates are concentrically embedded in the upper surface, and a magnetic material attached to the lower part of the magnetic pole plate so as to form a predetermined space between the magnetic pole plate. and highly flexible rubber-like plastic magnets made of rare earth or ferrite, arranged concentrically within the space so that the same poles face each other in a direction parallel to the top surface of the magnetic pole plate. a fixed polarity magnet made of a permanent magnet with a large coercive force; an iron core provided concentrically between the fixed polarity magnets so as to be in contact with the lower surface of the magnetic pole plate; a polarity conversion magnet consisting of a permanent magnet with a small coercive force arranged concentrically between the iron core and the bottom plate so as to be in contact with each other; and a coil wound around the polarity conversion magnet to switch the direction of magnetization of the polarity conversion magnet. A round ring pole type permanent magnet chuck.