JPH0416925B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a magnetic attraction device using permanent magnets, and particularly to a permanent magnet type magnetic attraction device used as a hanging type magnetic attraction device or a platform type magnetic attraction device.

[Conventional technology]

A magnet base has the basic structure of a magnetic adsorption device. This has a cavity in which a cylindrical member can be fitted between a pair of magnetic pole members fixed via a polarization plate made of non-magnetic material, and a cylindrical or almost cylindrical permanent magnet is magnetized in the radial direction in this cavity. It is constructed by rotatably fitting a magnet.

Then, each of the permanent magnets is in an attracted state in a state in which each magnet is in contact with one of the magnetic pole members, and is in a non-attracted state in a state in which each of the permanent magnets is in an intermediate position between the two magnetic pole members.

[Problem to be solved by the invention]

In order to apply this structure to, for example, a hanging magnetic adsorption device, it is necessary to attach hanging means to each of the pair of magnetic pole members, which makes the structure complicated. Moreover, since the magnetic attraction force is determined by a single permanent magnet, some kind of countermeasure must be taken to increase the attraction force. For example, by using materials with good magnetic properties,
Something like using a large magnet.

The present invention has been made in consideration of the above points, and an object of the present invention is to provide a permanent magnet type magnetic attraction device that is compact but has a strong magnetic attraction force.

[Means to solve the problem]

In order to achieve this objective, the present invention includes a first magnetic pole member having a substantially U-shape, and a first magnetic pole member disposed inside the U-shaped opening of the first magnetic pole member,
a second magnetic pole member whose end surface forms an adsorption surface together with the end surface of the first magnetic pole member; and a pair of magnetic pole members provided near the tip of the opening between the first and second magnetic pole members in the opening. a fixed magnet; a cylindrical space provided inside the opening between the first and second magnetic pole members in the opening; and a rotating magnet magnetized in the radial direction and inserted into the cylindrical space. A permanent magnet type magnetic adsorption device equipped with a magnet is provided.

〔Example〕

FIG. 1 shows the magnetic adsorption structure that forms the basis of the present invention. Reference numerals 1 and 1 are a pair of magnetic pole members arranged with a planar joint surface in between, polarization plates 2a made of non-magnetic material, Polarization plates 2a, 2 are fixed to each other via 2b, 2c, and are at the mutually fixed portion of both members 1, 1.
A movable permanent magnet 3 and a fixed permanent magnet 4 are provided in the portions where b and 2c are not provided.

The movable permanent magnet 3 has a substantially cylindrical shape with a circular cross section, and the arcs of opposing portions are cut out to form a straight line, and is rotatably fitted into a cylindrical cavity in which a mutually fixed portion of the magnetic pole members 1, 1 is formed. . Also fixed magnet 4
is fixed to the mutually fixed portion of the magnetic pole members 1,1.

The movable magnet 3 is magnetized in the diametrical direction so that the circular arc portions in the cross section become magnetic poles, and the fixed magnet 4 is magnetized in the thickness direction from one side of the magnetic pole members 1 to the other. Both magnets 3 and 4 generate approximately equal magnetic fluxes.

In this magnetic attraction device, when the movable magnet 3 is in the illustrated state, that is, when the magnetic poles of the movable magnet 3 and the fixed magnet 4 facing each one of the magnetic pole members 1 are different, the magnetic flux path is closed inside the magnetic attraction device. No magnetic flux appears externally (indicated by a broken line in the figure).

On the other hand, when the movable magnet 3 is rotated 180 degrees to have the polarity shown in parentheses, the same poles of the movable magnet 3 and the fixed magnet 4 face each other of the magnetic pole members 1, so the magnetic pole members 1, When a magnetized object (not shown) is interposed between the magnets 1 and 1, a magnetic flux passes through it so as to attract it (shown by a solid line in the figure).

At this time, the fixed magnet 4 and the rotating magnet 3 have the same polarity and repel each other, weakening the magnetic force of the rotating magnet 3. However, by reducing the thickness of the fixed magnet 4, this effect can be completely eliminated. be able to. This avoids a decrease in the magnetic force of the rotating magnet, which is inevitable with magnets of the same shape.

By rotating the movable magnet 3 in this way, the magnetic attraction device can be switched between the attraction state and the non-adsorption state, and in this case, the attraction surface formed by the magnetic pole members 1, 1 attracts the round bar-shaped magnetic conductive object. It has a shape suitable for lifting and transporting round rod-shaped objects.

FIG. 2 shows an embodiment of the present invention, in which the attracting surface and each magnetic circuit element are arranged so as to be suitable for attracting a flat magnetic conductive object. In this case, one magnetic pole member 11a has a U-shaped cross section, and the other magnetic pole member 11b has a shape that connects the U-shaped opening ends of the magnetic pole member 11a.
One movable magnet 13 and two fixed magnets 14, 14 are arranged between a and 11b. 12a and 12b are polarization plates.

In this configuration, since the attracting part of the magnetic pole member 11a and the attracting part of the magnetic pole member 11b are quite apart from each other, even a flat object can be attracted while maintaining its flat state.

This is important for a suspended type magnetic adsorption device and a platform type magnetic adsorption device.

FIG. 3 shows another embodiment of the present invention,
The direction of the fixed magnet in the embodiment shown in FIG. 2 is changed so that it becomes longer in the height direction, thereby reducing the dimension in the width direction.

This embodiment is also suitable for suctioning relatively flat objects. In the figure, 21a and 21b are magnetic pole members, 22a and 22b are polarization plates, 23 is a movable magnet, and 24 is a fixed magnet.

The magnets to be used in the apparatus of the present invention include fixed magnets such as ferrite magnets, which have a relatively small residual magnetism but a large coercive force, and rotating magnets such as alnico or rare earth magnets, which have a relatively large residual magnetism. Furthermore, both the fixed and movable magnets can be constructed of magnets with large coercive force, that is, ferrite magnets. The magnet can be made isotropic with relatively low residual magnetism.

When the fixed magnet is made of ferrite and the movable magnet is made of alnico, the residual magnetism is considered to be 3:1 to 2.5:1 at the operating point, so the fixed magnet has a long magnetic pole face, but the thickness can be reduced.

〔Effect of the invention〕

As described above, the present invention provides a pair of magnetic pole members including a U-shaped first magnetic pole member and a second magnetic pole member arranged inside the first magnetic pole member, and a pair of magnets and a rotating magnet. Since the permanent magnet type magnetic adsorption device is constructed with a small size, the magnetic adsorption force is strong, and it can support the U-shaped magnetic pole member, making it possible to create a permanent magnet type magnetic adsorption device with a simple hanging structure or platform type configuration. can be provided. Further, since the amount of magnetic flux between the fixed magnet and the movable magnet can be arbitrarily selected, the magnetic balance when not attracted can be changed to a reverse excitation magnetic state to improve the peelability of the workpiece.

[Brief explanation of drawings]

Fig. 1 is a diagram showing a magnetic attraction structure forming the basis of the present invention, Fig. 2 is a diagram showing an embodiment of the present invention, and Fig. 3 is a diagram showing an embodiment of the present invention.
The figure shows another embodiment of the invention. 1, 11, 21...Magnetic pole member, 2, 12, 22
... Polarization plate, 3, 13, 23 ... Fixed magnet, 4,
14, 24...Rotating magnet.

Claims (1)

[Scope of Claims] 1. A first magnetic pole member having a substantially U-shape, and an end surface of the first magnetic pole member disposed inside the U-shaped opening of the first magnetic pole member; a second magnetic pole member that together forms an attraction surface; a pair of fixed magnets provided near the tip of the opening between the first and second magnetic pole members in the opening; A permanent magnet type magnetic attraction comprising: a cylindrical space provided inside the opening between the first and second magnetic pole members; and a rotating magnet magnetized in the radial direction and inserted into the cylindrical space. Device. 2. In the device according to claim 1,
A permanent magnet type magnetic attraction device, wherein a pair of vertically long spaces are formed between the first and second magnetic pole members, and a pair of vertically long magnets magnetized in the thickness direction are provided in the pair of vertically long spaces. 3. In the device according to claim 1, a pair of vertically long spaces are formed between the first and second magnetic pole members, and a pair of horizontally long spaces magnetized in the thickness direction are formed in the pair of horizontally long spaces. A permanent magnet type magnetic adsorption device equipped with a magnet.