JPH01216737A - Magnetic fixing device - Google Patents

Abstract

PURPOSE:To easily carry out a switching operation even when adsorbing force is increased by rotating a movable permanent magnet between a first portion opposite to a fixed permanent magnet of opposite polarity and a second position opposite to fixed permanent magnet of the same polarity. CONSTITUTION:By rotating an operating screw 52, when a movable permanent magnet 44 is placed in a first position via a pinion 48 and a rack 46, in a first magnetic-pole piece 28 which is in contact with the N pole of a fixed permanent magnet 34, the pole face thereof opposite to the contacting face is brought into contact with the movable permanent magnet 44 of S pole, causing an operating face 22 to be in an unexcited condition. On the other hand, when the movable permanent magnet 44 is moved approx. 45 deg. to a second position, the pole face opposite to the contacting face of the first magnetic-pole piece 28 which in contact with the N pole of the fixed permanent magnet 34 is brought into contact with the movable permanent magnet 44 of N pole, causing the operating face 22 to be an excited condition. Thereby, a rotation resistance at the time of selectively switching over the operating face to an excited condition and an unexcited condition can be reduced while easily carrying out the switching operation even when adsorbing force is increased.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to a magnetic fixing device that releasably fixes a magnetic material using a plurality of permanent magnets, and particularly relates to a magnetic fixing device that uses a plurality of permanent magnets to releasably fix a magnetic material. The present invention relates to a magnetic fixing device including a plurality of magnetic pole sections arranged at equal angular intervals around an axis.

(Prior art) A magnetic fixing device with a circular work surface that attracts a magnetic material uses a plurality of magnetic pole pieces arranged at equal angular intervals around an axis perpendicular to the work surface that attracts a magnetic material. , there is a device including a plurality of permanent magnets arranged around the axis at the same pitch as the magnetic pole pieces. This magnetic fixing device selectively switches the working surface between an energized state and a de-energized state by angularly rotating the permanent magnet portion and the magnetic pole piece around the axis (Japanese Utility Model Publication No. 57-3256
Publication No. 9).

(Problem to be Solved by the Invention) However, in the magnetic fixing device, when the work surface is in an excited state, all the magnetic flux passes through the permanent magnet and the magnetic pole piece. There is a problem in that the magnetic flux acts as a switching resistor when selectively switching the work surface into energized and de-energized states.

For this reason, a permanent magnet type magnetic fixing device, which is equipped with multiple magnetic pole parts arranged at equal angular intervals around an axis perpendicular to the work surface, can move the work surface into an energized state and a de-energized state when the attraction force is increased. Since the so-called switching operation that selectively changes the state becomes difficult, it is only used as a device that does not require a large adsorption force like a magnetic chuck for grinding, and It is not used as a device that requires suction power.

The present invention provides a plurality of magnetic poles arranged at equal angular intervals around an axis intersecting the work surface, which makes it easy to selectively switch the work surface between an energized state and a de-energized state even when the attraction force is increased. An object of the present invention is to provide a permanent magnet type magnetic fixing device including a portion.

(Means for Solving the Problems) The magnetic fixing device of the present invention has a plurality of magnetic poles arranged at equal angular intervals with a non-magnetic material in between, around an axis that intersects a work surface that attracts a magnetic material. a plurality of fixed permanent magnets disposed between the magnetic pole sections so that their magnetic pole faces face the magnetic pole sections; and a plurality of fixed permanent magnets arranged around the axis and corresponding to the magnetic pole sections. a plurality of movable permanent magnets disposed equiangularly spaced about said axis and angularly rotatable about said axis, each one pole face being opposite said working face of said pole section; a plurality of movable permanent magnets slidably opposed to the sides and angularly rotating the movable permanent magnets about the axis to selectively place the work surface in an energized state and a de-energized state; It is characterized in that it includes a means for converting.

The fixed and movable permanent magnets are respectively arranged at the same pitch as the arrangement pitch of the magnetic pole parts, and the magnetization directions are alternately reversed in the respective arrangement directions. is preferred.

The fixed and movable permanent magnets and the magnetic pole portions are
It is preferable that each of them be arranged in multiple ways.

(Operation and Effect of the Invention) The movable permanent magnet has a first position facing the magnetic pole part, in which the magnetic pole face facing the magnetic pole part is given a polarity different from the polarity of the fixed permanent magnet, and a first position facing the magnetic pole part; is rotated angularly between its polarity and a second position opposite the other pole portion, which is provided with the same polarity by a fixed permanent magnet.

when the movable permanent magnet is moved to the first position;
Since the magnetic pole sections are magnetically connected to differently polarized pole faces of the fixed and movable permanent magnets, the fixed and movable permanent magnets are magnetically shorted by the opposing magnetic pole sections. Therefore, the magnetic flux of the fixed and movable permanent magnets does not leak to the work surface, and the work surface is kept in a de-energized state.

On the other hand, when the movable magnet is moved to the second position, the magnetic flux of the fixed permanent magnet is equal to its N
From the magnetic pole part facing the pole, through the working surface to the other magnetic pole part facing the S pole of the fixed permanent magnet. Similarly, the magnetic flux of a movable permanent magnet passes from a magnetic pole section magnetically connected to its north pole, through the working surface, to another magnetic pole section magnetically connected to the south pole of said movable permanent magnet. . For this reason,
The magnetic flux of both permanent magnets will pass through the working surface, and the working surface will be in an energized state.

According to the magnetic fixing device of the present invention, when the work surface is in an excited state, the magnetic flux that passes between the movable permanent magnet and the magnetic pole portion is only the magnetic flux of the movable permanent magnet, that is, the magnetic material is attracted. The magnetic flux is half of the magnetic flux contributing to . Therefore, for example, if the magnetic fixing device of the present invention has the same attraction force as the conventional magnetic fixing device, the rotational resistance when selectively switching the work surface between the energized state and the de-energized state is lower than that of the conventional magnetic fixing device. From one-fourth to one-half of the device,
Therefore, even if the adsorption force is increased, the switching operation is easy.

According to the magnetic fixing device of claim (2), since fixed and movable permanent magnets are arranged for each magnetic pole site, the attraction force becomes larger.

According to the magnetic fixing device of claim (3), since the working surface is divided into small pieces, a thin magnetic material can be reliably attracted, and the magnetic fixing device can have a large working surface. .

(Example) Hereinafter, an example of the magnetic fixing device of the present invention shown in the drawings will be described.

The magnetic fixing device 20 shown in FIGS. 1 and 2 includes a magnetic circuit block 24 that defines a circular, star-ball-shaped working surface 22, and a cylindrical housing 26. The magnetic circuit block 24 includes first and second sector-shaped pole pieces 28.30 located inside the housing 26. 1st
and second pole pieces 28 , 30 alternate at equal angular intervals around the axis of the magnetic circuit block 24 , or an axis passing through the center of the working surface 22 and perpendicular to the working surface 22 , so as to define the working surface 22 . It is located in

Each first pole piece 28 is made integrally with the housing 26. However, the housing 26 and each first pole piece 2
8 may be a separate member.

If housing 26 and each first pole piece 28 are separate members, housing 26 may be made of a non-magnetic material. The second pole piece 30 is integrally connected to the housing 26 and the first pole piece 28 by a spacer 32 made of non-magnetic material.

A fixed permanent magnet 34 is located between the first and second pole pieces 28,30, respectively.
The magnetic pole pieces 28, 30 of The magnetization direction of the fixed permanent magnets 34 is alternately reversed such that the north pole of the permanent magnet 34 contacts the first pole piece 28 and the south pole contacts the second pole piece 30, respectively.

Although the fixed permanent magnet 34 has a rectangular shape in the illustrated example, it may have a circular shape. Additionally, fixed permanent magnets 34 are attached to all first and second pole pieces 28.
If placed between 30 and 30, the suction power can be increased, but
Fixed permanent magnets 34 may be arranged, for example, between every other magnet.

In this case, each fixed permanent magnet 34 has a magnetization direction of
They are arranged so that they are the same, and the parts where fixed permanent magnets are not arranged are made of non-magnetic material or voids.

A recess 36 is formed in the magnetic circuit block 24 and opens on the side opposite to the work surface 22. In the recess 36, a disc-shaped base 38 made of a magnetic material and a disc 40 made of a non-magnetic material fixed on the base are arranged coaxially with the work surface 22 and connected to the magnetic circuit block 26. is arranged rotatably around the axis of. The base 38 includes a shaft portion 42 rotatably received in a hole drilled in the magnetic circuit block 24 so as to pass through the center of the work surface 22.

The disk 40 has a hole through which the shaft portion 42 passes.

The shaft portion 42 may be formed of a magnetic material,
It may be made of non-magnetic material.

A plurality of holes are formed in the disk 40 around the axis of the magnetic circuit block 24 at the same pitch as the arrangement pitch of the magnetic pole pieces 28,30. A movable permanent magnet 44 is arranged in each type. The magnetization direction of each movable permanent magnet 44 is alternately reversed, and the upper magnetic pole surface is the first
and the lower surface of the second magnetic pole piece 28 , 30 is slidably contacted, and the lower magnetic pole surface is in contact with the base 38 .

Note that if the same number of movable permanent magnets 44 as the first and second magnetic pole pieces 28 and 30 are arranged, the attraction force can be increased. The same number of movable permanent magnets 44 as pieces 28 may be arranged. In this case, each movable permanent magnet 44 is arranged so that its magnetization direction is the same, and a magnetic material is arranged in a region where no movable permanent magnet is arranged.

The materials, shapes, and dimensions of the fixed and movable permanent magnets 34 and 44 are such that the total magnetic flux of the fixed permanent magnets 34 and the total magnetic flux of the movable permanent magnets 44 are the same, or
The total magnetic flux of the movable permanent magnets 44 is selected to be slightly greater than that of the fixed permanent magnets 34. The fixed and movable permanent magnets 34 and 44 are preferably plate-shaped high coercive force magnets such as ferrite magnets.
A low coercive force magnet such as an alnico magnet may also be used.

A rack 46 is provided on the lower outer periphery of the base 38 and extends along an arc centered on the axis of rotation of the base 38.

The pinion 48 that meshes with the rack 46 is supported by a non-magnetic end plate 50 fixed to the lower surface of the housing 26.
The operating screw 52 that rotates the pinion 48 is located in the housing 2
'6 is rotatably supported. The operating screw 52 is meshed with the pinion 48. Therefore, the operating screw 52 acts as a worm, and the pinion 48 also acts as a wheel.

In the illustrated example, a hole is formed in the head of the operating screw 52 to receive a hexagonal wrench in order to rotate the operating screw 52. However, a handle for operation may be attached to the operation screw 52.

When the operating screw 52 is rotated, the base 38, the disk 40, and the movable permanent magnet 44 are moved to the magnetic circuit block 2 by the joint action of the operating screw 52, the pinion 48, and the rack 46.
rotated angularly about the axis of 6.

In order to angularly rotate the movable permanent magnet 44, a second
As shown in the figure, a hole 54 may be formed at the end of the shaft portion 42 to receive a hexagonal wrench. Similarly, a hole for receiving a hexagonal wrench may be formed on the lower surface of the base 3°8.

The angular rotation of the movable permanent magnet 44 causes the movable permanent magnet 4
4, a first position facing the pole piece in which the magnetic pole face facing the magnetic pole piece 28, 30 is given a polarity different from this polarity by a fixed permanent magnet 34; The same polarity is confined between a second position opposite the other pole piece provided by a fixed permanent magnet 34.

When the movable permanent magnet 44 is moved to the first position,
The first pole piece 28 contacts the north pole of the fixed permanent magnet 34
The second magnetic pole piece 30 is in contact with the movable permanent magnet 44 whose magnetic pole surface facing this is the south pole, and the second magnetic pole piece 30 which contacts the south pole of the fixed permanent magnet 34 is a movable permanent magnet whose magnetic pole surface facing this is the north pole. It is brought into contact with a permanent magnet 44.

Therefore, the magnetic flux of the fixed and movable permanent magnets includes the N pole of the fixed permanent magnet, the first magnetic pole piece 28 facing it, the S pole of the movable permanent magnet facing it, and the N pole of the permanent magnet. , the base 38, the south pole of the other movable permanent magnet, the north pole of this permanent magnet, the second magnetic pole piece 30 opposing this, and the south pole of the fixed permanent magnet opposing this. As a result, the fixed and movable permanent magnets 34.44 are magnetically short-circuited, so that the magnetic flux of the fixed and movable permanent magnets 34.44 does not leak to the working surface 22, and the working surface 22 is in a de-energized state. It will be destroyed.

On the other hand, when the movable permanent magnet 44 is moved to a second position, that is, in the illustrated example, rotated 45 degrees in FIG. The magnetic pole piece 28 is in contact with a movable permanent magnet 44 whose magnetic pole face facing the N pole is in contact with the movable permanent magnet 44, and the second magnetic pole piece 30 which is in contact with the S pole of the fixed permanent magnet 34 is in contact with the magnetic pole face facing the S pole piece.
The poles are brought into contact with movable permanent magnets 44 .

Thereby, the magnetic flux of the fixed permanent magnet 34 is transferred from the first pole piece 28 in contact with the north pole face thereof, through the working surface 22, to the second pole piece 30 facing the south pole face of the fixed permanent magnet 34.
and the S pole of the fixed permanent magnet. In addition, the magnetic flux of the movable permanent magnet 44 is transmitted to its north pole face, the first pole piece 28 facing it, the working surface 22, the second pole piece 30, and other movable permanent magnets in contact with it. via the south pole, the north pole of the other movable permanent magnet, the base 38 and the south pole of the first movable permanent magnet. Therefore, the magnetic flux of both permanent magnets 34, 44 passes through the working surface 22, and the working surface 22 is placed in an excited state.

When the work surface 22 is in an excited state, the magnetic flux passing through the movable permanent magnet 44 is only that of the movable permanent magnet 44. Therefore, if the attraction force is the same as that of the conventional magnetic fixing device, the work surface The rotational resistance when selectively switching the magnet 22 between the energized state and the de-energized state can be one-fourth to one-half that of conventional magnetic fixing devices, so even if the attraction force is increased,
Easy switching operation.

The movable permanent magnet 44 may be rotated around the axis of the magnetic circuit block 24, and the mechanism shown in the third Kokuto and FIG. 4 may be used as the switching mechanism.

In the switching mechanism shown in FIGS. 3 and 4, a hole 56 is formed in the base 38 from its outer peripheral surface toward the center, and
A long hole 58 is formed in the housing 26 and extends in the circumferential direction thereof. An operating rod such as a hexagonal wrench or a driver is inserted into the hole 56 via the elongated hole 58. The base 38 and the movable permanent magnet 44 are rotated by rotating the operating rod in the circumferential direction of the housing 26.

The operating rod may be removable from the base 38, and may be attached to the base so as to protrude outward from the housing 26 from the hole 56 through the elongated hole 58, as shown by reference numeral 60 in FIG. It may be fixedly provided in 3B.

As a switching mechanism for rotating the movable permanent magnet 44 around the axis of the magnetic circuit block 24, as in the switching mechanism shown in FIG. A mechanism for rotating the movable permanent magnet 44 by rotating it in the circumferential direction of the magnet 26 can be used.

In this case, the disc 40 may be rotatable with respect to the base 38.

The magnetic fixing device 70 shown in FIG. 7 and FIG.
By arranging a cylindrical spacer 72 made of a non-magnetic material around the shaft portion 42 of the housing 8, the shaft portion 42 is magnetically separated from the cabinet 1 and the second pole piece 28, 30, and the housing By making 26 of a non-magnetic material, the housing 26 and the first and second pole pieces 28, 30 are magnetically separated.

In the magnetic fixing device 70, the movable permanent magnet 44
When the first magnetic pole piece 28 contacts the N pole of the fixed permanent magnet 34, the opposite magnetic pole surface contacts the movable permanent magnet 44 of the S pole, and the fixed permanent magnet 34 3
The second magnetic pole piece 30 that contacts 5FiA of No. 4 has its opposite magnetic pole surface in contact with a movable permanent magnet 44 having an N pole. For this reason, the fixed and movable permanent magnets 34, 44 are magnetically short-circuited, so that the fixed and movable permanent magnets 34, 44 are magnetically short-circuited.
．． 44 does not leak to the work surface 22, and the work surface 22 is left in a de-energized state.

On the other hand, when the movable permanent magnet 44 is moved to the second position, that is, in the illustrated example, to a position rotated by 45 degrees in FIG. The magnetic pole piece 2B has its opposing magnetic pole surface in contact with a movable permanent magnet 44 having an N pole, and the S of the fixed permanent magnet 34.
The second magnetic pole piece 30 that contacts the pole is brought into contact with a movable permanent magnet 44 whose magnetic pole face facing the second pole piece has an S pole. For this reason,
The magnetic flux of both permanent magnets 34, 44 passes through the working surface 22, which is then placed in an energized state.

The magnetic fixing device 80 shown in FIG. 9 and FIG.
The second magnetic pole pieces 28, 30, a fixed permanent magnet 34, and a movable permanent magnet 44 are arranged in multiple layers. The internally disposed pole pieces 28 30 , the fixed permanent magnet 34 and the movable permanent magnet 44 each have an angular spacing of 90 degrees about the axis of the magnetic circuit block 24 . In contrast, the outer pole pieces 28 , 30 , the fixed permanent magnet 34 and the movable permanent magnet 44 each have an angular spacing of 30 degrees about the axis of the magnetic circuit block 24 .

The inner pole piece and the outer pole piece are magnetically insulated by a spacer 82 of non-magnetic material. The housing 26 is made of non-magnetic material, and
It is made integrally with the end plate 50. Shaft portion 42 of base 38
is made of non-magnetic material to prevent the pole pieces located inside from being magnetically shorted.

Although not shown, the magnetic fixing device 80 also includes a switching mechanism for angularly rotating the movable permanent magnet 44 around the axis of the magnetic circuit block 24.

The work surface 22 of the magnetic fixing device 80 is also a magnetic fixing bag v120.
Similar to and 70, the movable permanent magnet 44 has been moved to the first position. and fixed and movable permanent magnets 34
．． Since 44 is magnetically shorted, it is left in a de-energized state. On the other hand, when the movable permanent magnet 44 is moved to a second position, that is, in the example shown rotated 90 degrees in FIG. As a result, the work surface 22 is placed in an energized state.

Magnetic fixing device shown in Figures 11 and 12 9
0 has a triple arrangement of first and second magnetic pole pieces 28, 30, a fixed permanent magnet 34, and a movable permanent magnet 44.

The innermost pole pieces 28 , 30 , the fixed permanent magnet 34 and the movable permanent magnet 44 each have an angular spacing of 45 degrees about the axis of the magnetic circuit block 24 . The intermediately arranged pole pieces 28 , 30 , the fixed permanent magnet 34 and the movable permanent magnet 44 each have an angular spacing of 30 degrees around the axis of the magnetic circuit block 24 . The outermost pole pieces 28 , 30 , the fixed permanent magnet 34 and the movable permanent magnet 44 each have an angular spacing of 22.5 degrees about the axis of the magnetic circuit block 24 .

The innermost magnetic pole piece and the middle magnetic pole piece are magnetically insulated by a spacer 92 made of a non-magnetic material, and the middle magnetic pole piece and the outermost magnetic pole piece are magnetically insulated. are magnetically insulated by spacers 94 made of non-magnetic material. Housing 26 is made of non-magnetic material. A cylindrical spacer 96 made of a non-magnetic material is arranged around the shaft portion 42 of the base 38.

The innermost movable permanent magnet 44 is disposed on the first base 38a, and the middle movable permanent magnet 44 is disposed on the first base 38a.
The outermost movable permanent magnet 44 is arranged on a third base 38c that is angularly rotatable with respect to the second base 38b. ing.

The bases 38a, 38b, 38c have two sets of holes 56a, 56b, 56 extending from the outer peripheral surface toward the center, respectively.
c is formed. The housing 26 has a hole 56a;
Elongated holes 58a, 58b, 5.corresponding to 56b, 56c.
8c is formed.

Magnetic fixing device 90 also includes magnetic fixing devices 30.70 and 8.
Similarly to 0, when the movable permanent magnet 44 is moved to the first position, the fixed and movable permanent magnets 34, 44 are magnetically shorted and are therefore de-energized.

On the other hand, when the work surface 22 is in a de-energized state, the first base 38a is rotated by 45 degrees, and the movable permanent magnet 44 disposed at the innermost position is moved to the second position. Then, since the magnetic flux of the fixed and movable permanent magnets 34 and 44 arranged at the innermost side passes through the working surface 22, the working surface 22
is placed in an excited state.

Further, when the second base 38b is rotated 30 degrees and the movable permanent magnet 44 disposed in the middle is moved to the second position, the fixed and movable permanent magnet 34 disposed in the middle.
44 passes through the working surface 22, the working surface 22 is energized.

Further, when the third base 38c is rotated 22.5 counterclockwise and the outermost movable permanent magnet 44 is moved to the second position, the outermost fixed and movable permanent magnets 44 are moved to the second position. Since the magnetic flux of the magnets 34, 44 passes through the working surface 22, the working surface 22 is placed in an energized state.

According to the magnetic fixing device 90, since the first, second, and third bases 38a, 38b, and 38c are each independently rotatable, it is possible to change the amount of magnetic flux that contributes to the attraction of the magnetic material. .

The magnetic fixing devices 20, 70, 80, and 90 can be used by superimposing two sets of magnetic fixing devices 70, as shown in FIG. 13, which shows an embodiment of the magnetic fixing device 70. The end plates 50 of both magnetic fixing devices F0 have been removed. Both magnetic fixing devices 70 are coupled by a plurality of bolts 98. In this combination device, one magnetic fixing device is used as a means for attaching the combination device to a machine tool or the like, and the other magnetic fixing device is used as a means for attracting a magnetic material.

Working surface 22 of magnetic fixing device 20.70.80 and 90
can be rectangular, like the magnetic fixing device 100 shown in FIG. 15 and the magnetic fixing device 102 shown in FIG. 16. The magnetic fixing device 100 has the same structure as the magnetic fixing device 20 except that the housing 102 has a rectangular tubular shape to provide a rectangular work surface.

The magnetic fixing devices 20, 70, 80, and 90 can also be used as a magnetic fixing device assembly 104 that includes a plurality of magnetic fixing devices, as shown in FIG. Although the magnetic fixing device assembly 104 includes two magnetic fixing devices 100, it may be a magnetic fixing device assembly including three or more magnetic fixing devices.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing an embodiment of the magnetic fixing device of the present invention, with a part of the magnetic circuit block and housing cut away to show part of the switching mechanism. 2-
3 is a sectional view taken along line 2, FIG. 3 is a sectional view similar to FIG. 2 showing another embodiment of the switching mechanism, and FIG. 4 is taken along line 4-- in FIG.
FIG. 5 is a sectional view similar to FIG. 2 showing still another embodiment of the switching mechanism; FIG. 6 is a second diagram showing still another embodiment of the switching mechanism. 7 is a plan view showing another embodiment of the magnetic fixing device, FIG. 8 is a sectional view taken along line 8-8 in FIG. 7, and FIG. 9 is a magnetic fixing device. FIG. 10 is a sectional view taken along the to-to line in FIG. 9; FIG. 11 is a plan view showing still another embodiment of the magnetic fixing device; 12
The figure is a cross-sectional view taken along line 12-12 in Figure 11.
3 is an end view taken along the line 13-13 in FIG. 12, FIG. 14 is a sectional view showing an example of the use of the magnetic fixing device of the present invention, and FIG. FIG. 16 is a plan view showing yet another example of use of the magnetic fixing device of the present invention. 20.70,80,90,100,104: Magnetic fixing device, 22: Work surface, 24: Magnetic circuit block, 2
6.102: Housing, 2B, 30: Magnetic pole piece, 32: Non-magnetic spacer, 34
: Fixed permanent magnet, 38: Base, 44: Movable permanent magnet, 46: Rack, 48: Binion, 52: Operating screw, 54, 56, 58: Hole. Agent Patent Attorney Nobuyuki Matsunaga Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 15 Figure 100

Claims (3)

[Claims] (1) A magnetic circuit means having a plurality of magnetic pole parts arranged at equal angular intervals with a non-magnetic material in between around an axis intersecting a work surface that attracts a magnetic substance, and a magnetic circuit means having a plurality of magnetic pole parts arranged at equal angular intervals with a non-magnetic material in between; a plurality of fixed permanent magnets arranged such that their magnetic pole faces face the magnetic pole portions; a plurality of movable permanent magnets arranged angularly and rotatably in a plurality of movable permanent magnets, each of which has one pole face slidably opposed to a side of the magnetic pole section opposite the working surface; and switching means for angularly rotating the movable permanent magnet about the axis to selectively place the work surface in an energized state and a de-energized state. (2) The fixed and movable permanent magnets are respectively arranged at the same pitch as the arrangement pitch of the magnetic pole parts, and the magnetization directions are alternately reversed in the respective arrangement directions, The magnetic fixing device according to claim (1). (3) Claim (1), wherein the fixed and movable permanent magnets and the magnetic pole portions are each arranged in multiples.
Or the magnetic fixing device according to (2).