JP2012151989A - Magnet assembly - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a magnet assembly 30 having an enhanced density of magnetic flux extending from a magnetic pole (N, S) to the outside thereof.SOLUTION: The magnet assembly 30 has tabular permanent magnets 11 magnetized in a direction of its thickness and non-tabular yoke parts 12 and 13, provided that the tabular permanent magnets 11 and the non-tabular yoke parts 12 and 13 are alternately laid out along a line, the permanent magnets 11 are changed in orientation alternately to be inclined opposite to each other with respect to the direction of the normal to the line, and the yoke parts are assigned for magnetic pole and for short circuit alternately. In the magnet assembly, an open angle θ formed between permanent magnets between which one yoke part 13 for magnetic pole is made an acute angle. In addition, the total length (W×2) of the adjacent permanent magnets between which one yoke part 13 for magnetic pole is sandwiched is made equal to or larger than 1.42 (about √2) times of the magnetic pole length L of the adjacent two permanent magnets. Preferably, the yoke part 13 for magnetic pole is shaped in an isosceles triangle in a cross section.

Description

  The present invention relates to a magnet body in which flat permanent magnets and non-flat yoke portions are arranged in a line in an alternating arrangement, and more specifically, the permanent magnets are alternately changed in direction and inclined. The present invention relates to a magnet body in which iron portions are alternately used for magnetic poles and short circuits.

  In a conventional linear motor (see FIGS. 7A to 7C), a coil (armature) is used for the mover, and a magnet body (permanent magnet field) including a permanent magnet is used for the stator. It was. This magnet body is made by arranging a permanent magnet and a yoke (a yoke) adjacent to each other in a straight line (a straight line). Both the permanent magnet and the yoke part are a flat plate or a rectangular parallelepiped having a rectangular cross section. It was formed in a shape and mounted either in a state parallel to or perpendicular to the line direction and the adjacent arrangement direction. In such a conventional magnet body, a permanent magnet having a rectangular shape that is easy to form is used, but since a relatively expensive permanent magnet is used in a larger amount than a relatively inexpensive yoke part, Cost reduction is difficult.

  On the other hand, in the permanent magnet type rotary motor, a rotor (permanent magnet field, endless mover) in which a flat permanent magnet magnetized in the thickness direction is embedded in a cylindrical yoke has been developed. In the initial rotor 10 (see FIG. 7D and Patent Document 1), a flat permanent magnet 11, a flat short-circuiting yoke 12, a flat permanent magnet 11, and a fan in cross section are non-flat. The magnetic pole yoke parts 13 are arranged in a circle (one line) in an alternating arrangement. The permanent magnet 11 sends all the magnetic fluxes from the front and back sides to the yoke parts 12 and 13, and the short-circuiting yoke part 12 bridges the permanent magnets 11 and 11 adjacent to each other by containing the magnetic flux inside. Thus, the magnetic pole yoke portion 13 outputs the magnetic fluxes coming from the adjacent permanent magnets 11 and 11 to the outside, and alternately forms N magnetic poles and S magnetic poles.

  In this rotor 10, the opening angle θ between the permanent magnets 11, 11 sandwiching the magnetic pole yoke portion 13 was a right angle (see FIG. 7D and Patent Document 1). In the child 20 (permanent magnet field, endless mover), the open angle θ between the permanent magnets 11 and 11 sandwiching the magnetic pole yoke portion 13 spreads to an obtuse angle (FIG. 7 (e) and Patent Documents 2 to 4). See). Such a rotor 20 is a magnet body in which flat plate-like permanent magnets 11 and non-plate-like yoke portions 12 and 13 are arranged in a circle (one line) alternately, and the permanent magnets 11 are alternately arranged. It corresponds to a magnet body whose direction is changed to be inclined and the yoke portions are alternately short-circuited yoke portions 12 and magnetic pole yoke portions 13.

  When the lower half of the rotor 20 in FIG. 7 (e) is specified as a portion including the N magnetic pole and the S magnetic pole, the plate-like first magnetized in the thickness direction of the magnet body in that portion is specified. 1 permanent magnet 11 (aa), a first magnetic pole yoke portion 13 (N) made of a ferromagnetic material, a plate-like second permanent magnet 11 (bb) magnetized in the thickness direction, and a ferromagnetic material. The short-circuiting yoke portion 12, the flat plate-shaped third permanent magnet 11 (cc) magnetized in the thickness direction, the second magnetic pole yoke portion 13 (S) made of a ferromagnetic material, and the magnetization in the thickness direction. The flat plate-shaped fourth permanent magnets 11 (dd) are arranged adjacent to each other in the order in a semicircle (single line) from the left to the bottom and to the right in the drawing, and the first permanent magnets 11 (aa) ) And the second permanent magnet 11 (bb) are arranged so that one end portions are close to each other and the other end portions are separated from each other so that the N pole surfaces face each other diagonally. The first magnetic pole yoke portion 13 (N) is an N magnetic pole that outputs a magnetic flux to the outside in a state of being loaded between both N pole surfaces, and the third permanent magnet 11 (cc) And the fourth permanent magnet 11 (dd) have their one end close to each other and the other end separated from each other, and their S pole faces are diagonally facing each other, and the first permanent magnet 11 (dd) is loaded between the two S pole faces. The yoke portion 13 (S) for two magnetic poles is an S magnetic pole for generating a magnetic flux to the outside, and the yoke portion 12 for short-circuiting is composed of the S pole surface of the second permanent magnet 11 (bb) and the third permanent magnet. The magnetic flux is accommodated in the state of being loaded between the 11 (cc) N pole surfaces.

Japanese Patent Laid-Open No. 9-9537 Japanese Patent Laid-Open No. 10-51984 JP 2009-112121 A JP 2009-284621 A

  In such a magnet-embedded magnet body, since the ratio of the permanent magnet to the yoke is small, cost reduction proceeds. Also, looking at the magnetic flux distribution state, the number of magnetic fluxes entering the magnetic pole yoke part from the adjacent permanent magnet is almost equal to the number of magnetic fluxes exiting from the magnetic pole surface of the magnetic pole yoke part. The ratio of the magnetic flux density of the magnetic pole face of the iron part to the magnetic flux density of the pole face of the permanent magnet is the ratio of the adjacent area of the permanent magnet to the magnetic pole yoke part and the magnetic pole area of the magnetic pole yoke part. For example, it is determined by the ratio of the total length of the adjacent permanent magnets sandwiching the yoke part for the magnetic pole and the magnetic pole length over the permanent magnets. As described above, the open angle between the permanent magnets is a right angle or an obtuse angle, Since the cross-sectional shape of the yoke portion is not a triangle but a sector, the ratio was less than 1.42 (about √2). In the conventional magnet body in the permanent magnet type rotary motor capable of narrowing the air gap between the stator and the rotor, the magnetic flux convergence capacity of the magnetic pole yoke portion that narrows the magnetic flux emitted from the permanent magnet toward the magnetic pole is 1.42 times. Some recommend an obtuse angle that is smaller and less than 1.

  By the way, in order to promote the cost reduction of the linear motor, it is considered that the permanent magnet field should be modified to a magnet body similar to the magnet embedded type. In other words, when making a linear magnet body in which N magnetic poles and S magnetic poles are alternately arranged, instead of using a permanent magnet or a yoke portion with a rectangular cross section as in the conventional product described above, After arranging the flat permanent magnets magnetized in the thickness direction and the non-flat yokes in a straight line (along line) in an alternating arrangement, the permanent magnets are alternately turned and slanted, The yoke portion for the magnetic pole is sandwiched between the permanent magnet surfaces of the same polarity and the yoke portion for the short circuit is sandwiched between the permanent magnet surfaces of the opposite polarity so that the yoke portions are alternately used for the magnetic pole and for the short circuit. Thereby, like the rotor of a permanent magnet type rotary motor, since the ratio of a yoke part goes up and the ratio of a permanent magnet falls, it is anticipated that cost will fall.

  However, linear motors used in railway linear motor cars and the like differ from permanent magnet type rotary motors in which the air gap is always kept constant, and as described above, the permanent magnet field is the stator and the armature is the mover. Even if the permanent magnet field is the mover and the armature is the stator, the air gap between the stator and the mover varies depending on the flying state and running state of the train. In order to prevent undesired contact between the stator and the mover, it is necessary to widen the air gap. For this purpose, it is necessary to increase the magnetic flux density in the air gap (hereinafter referred to as air gap magnetic flux density). For the magnet body for the permanent magnet field, the density of the magnetic flux that goes out from the magnetic pole (field magnetic pole) Is required to increase.

In order to increase the thrust and torque of the motor, it is straightforward to increase the magnetomotive force of the armature winding, but to reduce the copper loss in the armature winding and pursue higher efficiency, the armature It is necessary to minimize the influence of the coil magnetomotive force, that is, the armature reaction. For this reason, it is necessary to widen the air gap. From this viewpoint, the magnetic pole of the magnet body for the permanent magnet field is required. It is required to increase the magnetic flux density.
Therefore, it is a technical problem to increase the magnetic flux density of the magnetic poles in a magnet body in which flat permanent magnets and non-flat yoke portions are alternately arranged in a line.

The magnet body of the present invention has been created in order to solve such problems, but has been improved on the assumption that the following basic configuration is provided.
That is, the magnet body of the present invention includes a flat plate-shaped first permanent magnet magnetized in the thickness direction, a first magnetic pole yoke portion made of a ferromagnetic material, and a flat plate-shaped second permanent magnet magnetized in the thickness direction. A magnet, a short-circuiting yoke portion made of a ferromagnetic material, a plate-like third permanent magnet magnetized in the thickness direction, a second magnetic pole yoke portion made of a ferromagnetic material, and magnetized in the thickness direction A flat plate-like fourth permanent magnet is adjacently arranged in a line in that order, and the first permanent magnet and the second permanent magnet are close to one end and separated from the other end, and the N pole surface The first magnetic pole yoke portion is an N magnetic pole that emits a magnetic flux to the outside in a state where they are obliquely opposed to each other and loaded between both N pole surfaces, and the third permanent magnet and the first 4 permanent magnets have one end close to each other and the other end separated from each other so that the S pole faces face each other diagonally and are loaded between both S pole faces. In this state, the second magnetic pole yoke portion is an S magnetic pole that emits a magnetic flux to the outside, and the short-circuiting yoke portion is an S pole surface of the second permanent magnet and an N pole surface of the third permanent magnet. It is assumed that the magnetic flux is accommodated in the state of being loaded between. In the following description, when the features of the present invention are defined, the solving means 1 and 3 are defined by the opening angle, and the solving means 2 and 4 are defined by the magnetic pole length ratio, but this is not an essential difference. .

  That is, the magnet body of the present invention (Solution 1) is the magnet body having the basic configuration as described above, and the opening angle between the first permanent magnet and the second permanent magnet and the third permanent magnet. Each of the opening angles with the fourth permanent magnet is an acute angle.

  Further, the magnet body of the present invention (Solution means 2) is a magnet body having the basic configuration as the premise described above, and has a length from the end portion on the near side to the end portion on the remote side of the first permanent magnet. The total length of the second permanent magnet from the proximal end to the remote end is a remote end of the first permanent magnet for the N magnetic pole of the first magnetic pole yoke portion. At least 1.42 times the length of the magnetic pole extending between the first permanent magnet and the remote end of the second permanent magnet, and from the close end to the remote end of the third permanent magnet. The total length of the length of the second permanent magnet and the length of the fourth permanent magnet from the proximal end to the remote end is the separation of the third permanent magnet with respect to the S magnetic pole of the second magnetic pole yoke portion. It is 1.42 times or more of the magnetic pole length over the end part on the side and the end part on the separation side of the fourth permanent magnet. And butterflies.

  Furthermore, the magnet body of the present invention (Solution means 3) is the magnet body of the above-mentioned solution means 1, in which one or both of the first permanent magnet and the fourth permanent magnet are replaced with a non-magnetic material. And an end angle between the second permanent magnet and the third permanent magnet close to the end member and the end member is less than a half of a right angle. To do.

  Further, the magnet body of the present invention (solving means 4) is the magnet body of the above-mentioned solving means 2 and is made of a non-magnetic material instead of one or both of the first permanent magnet and the fourth permanent magnet. The end member is provided and has a length from the proximal end to the remote end of the second permanent magnet and the third permanent magnet that is closer to the end member. , Of the first magnetic pole yoke portion and the second magnetic pole yoke portion adjacent to the end member, the magnetic poles on the remote side of the permanent magnet and the remote side of the end member It is characterized by being 1.42 times or more of the magnetic pole length extending to the end.

  Further, the magnet body of the present invention (Solution means 5) is the magnet body of the above-mentioned solution means 1 and 2, and is provided with a bypass yoke portion in which a bypass intermediate portion made of a ferromagnetic material and a bypass end portion are connected. The detour end portion is adjacently arranged so as to extend one line adjacent arrangement to either one or both of the first permanent magnet and the fourth permanent magnet, and is adjacent thereto. A magnetic flux coming from a permanent magnet is contained inside and guided to the detour intermediate portion, and the detour intermediate portion is arranged at a location different from the N magnetic pole and the S magnetic pole, and from the detour end portion It is characterized in that the incoming magnetic flux is housed inside to bypass the N magnetic pole and the S magnetic pole.

In such a magnet body of the present invention (Solution 1), the opening angle between the permanent magnets was a right angle or an obtuse angle in the conventional product, whereas the opening angle was narrowed to an acute angle. The magnetic flux convergence ability of the magnetic pole yoke portion that narrows the magnetic flux emitted from the magnet toward the magnetic pole is improved as compared with the prior art.
Therefore, according to the present invention, it is possible to realize a magnet body in which flat permanent magnets and non-flat yoke portions are arranged in a line in an alternating arrangement and have a high magnetic flux density of magnetic poles.

Further, in the magnet body of the present invention (Solution means 2), the ratio of the pole length of the permanent magnet to the pole length of the magnetic pole yoke is less than 1.42 (about √2) in the conventional product. On the other hand, by increasing the magnetic pole length ratio to 1.42 or more, the magnetic flux convergence ability of the magnetic pole yoke portion for narrowing the magnetic flux emitted from the permanent magnet toward the magnetic pole is improved as compared with the conventional case.
Therefore, according to the present invention, it is possible to realize a magnet body in which flat permanent magnets and non-flat yoke portions are arranged in a line in an alternating arrangement and have a high magnetic flux density of magnetic poles.

  Furthermore, in the magnet body of the present invention (Solution means 3), the non-magnetic material is disposed at the end of the permanent magnet, but at the end of the permanent magnet, Corresponding to the fact that it has become only one side, by narrowing the opening angle to less than half of the right angle, that is, half of the acute angle, for the magnetic pole that narrows the magnetic flux emitted from the permanent magnet toward the magnetic pole even at the extreme end The magnetic flux convergence ability of the yoke part is improved as compared with the conventional case.

  Moreover, in the magnet body of the present invention (Solution means 4), the whole body is terminated by disposing the non-magnetic material at the end of the permanent magnet, and accordingly, at the end of the magnet body. However, even if only one permanent magnet is used, the magnetic pole length ratio is 1.42 or more, so that the magnetic flux generated from the permanent magnet is narrowed toward the magnetic pole even at the extreme end. The magnetic flux convergence ability of the iron part is improved as compared with the conventional one.

  Further, in the magnet body of the present invention (Solution means 5), since the magnetic path is closed and completed by providing the bypass yoke portion, it is used as a single short-ended magnet body. In addition, it is possible to make a long-ended magnet body by connecting a plurality of them, or to connect them at both ends to make them endless. Moreover, whenever a single magnet is used as a short-ended magnet body, and when a plurality of magnets are combined into a long magnet body, magnetic poles of the same polarity are connected at the connecting portion so that they are adjacent to each other. Therefore, the magnetic fluxes coming out of the magnetic pole surfaces reach farther because the magnetic fluxes are gathered toward the different polarities of the adjacent magnetic poles without being separated into the adjacent magnetic poles.

The structure of a magnet body is shown about Example 1 of this invention, (a) is a front view, (b) is a cross-sectional plan view of BB arrow, (c) is a magnetic flux distribution map. About Example 2 of this invention, the structure of a magnet body is shown, (a) is a cross-sectional top view and an edge part enlarged view, (b) is a magnetic flux distribution map. About Example 3 of this invention, the structure of a magnet body is shown, (a) is a front view, (b) is a cross-sectional plan view, (c) is a magnetic flux distribution diagram. It is the cross-sectional top view and end part enlarged view which show the structure of a magnet body about Example 4 of this invention. It is the magnetic flux distribution figure which concerns on the cross-sectional top view and an edge part enlarged view. About Example 5 of this invention, the structure of the linear motor which uses a magnet body as a needle | mover is shown, (a) is a cross-sectional top view of the principal part, (b) is a magnetic flux distribution map. (A)-(b) is a magnet arrangement example of the conventional linear motor, respectively, (d)-(e) is a magnet arrangement example of the rotor of the conventional permanent magnet embedded type motor, respectively.

About the magnet body of such this invention, the specific form for implementing this is demonstrated by the following Examples 1-5.
The first embodiment shown in FIG. 1 embodies the above-described solving means 1 and 2 (claims 1 and 2 as originally filed), and is shown in the second embodiment shown in FIG. 2 and the third embodiment shown in FIG. The third embodiment embodies the above-described solving means 3 to 4 (claims 3 to 4 at the time of filing), and the fourth embodiment shown in FIGS. The fifth embodiment shown in FIG. 6 is an example applied to a linear motor.

In addition, since the same reference numerals are given to the same constituent elements as those in the past in the illustration thereof, and what is described in the background art section is also common to the following embodiments, it is redundant. The description of this will be omitted, and the following description will focus on differences from the prior art.
Moreover, since the material and manufacturing method regarding a permanent magnet or a yoke part are sufficient, a description is omitted.
In any of the magnetic flux distribution diagrams, the magnetic flux lines are displayed as images with two-dot chain lines.

About the Example 1 of the magnet body of this invention, the specific structure is demonstrated referring drawings. 1A is a front view of a magnet body 30 and FIG. 1B is a cross-sectional plan view taken along the arrow BB.
The main differences between the magnet body 30 and the conventional rotor 20 described above are that the alternate arrangement of the permanent magnets and the yoke portion is not a circular arc but a straight line (a straight line), and an opening angle θ. And the total length (W × 2) of the adjacent permanent magnets sandwiching the magnetic pole yoke portion 13 is 1.42 (about √2) times or more of the magnetic pole length L across the permanent magnets. The cross-sectional shape of the magnetic yoke part 13 is an isosceles triangle, and the cross-sectional shape of the short-circuiting yoke part 12 is a trapezoid close to an isosceles triangle. The short-circuiting yoke portion 12 and the magnetic pole yoke portion 13 do not surround the permanent magnet 11 and are fixed by being sandwiched from both sides of the depth D by the holding member 31 made of nonmagnetic material.

  More specifically, the permanent magnet 11, the short-circuiting yoke part 12, and the magnetic pole yoke part 13 have the same depth D (indicated by the height in FIG. 1 (a)), and further have a cross section. Is the same everywhere in the depth D direction. Then, when the cross section is seen (refer FIG.1 (b)), all the permanent magnets 11 are the same rectangles, and all have the same thickness H and length W. In the adjacent arrangement direction, description will be made in order from one side (left side in the figure) to the other side (right side in the figure). First, the first permanent magnet 11 (aa) is rotated θ / 2 clockwise from the plane perpendicular to the line direction. And the S pole face is directed to one side (left side) and the N pole face is directed to the other side (right side).

  The next second permanent magnet 11 (bb) is inclined by θ / 2 counterclockwise from a plane perpendicular to the direction of one line, and the N pole face is directed to one side (left side) and the S pole face is placed on the other side ( (To the right) Further, the third permanent magnet 11 (cc) next to the first permanent magnet 11 (cc) is inclined by θ / 2 clockwise from the plane perpendicular to the straight line direction, like the first permanent magnet 11 (aa). Unlike (aa), the N pole face is directed to one side (left side) and the S pole face is directed to the other side (right side). The last fourth permanent magnet 11 (dd) is inclined by θ / 2 counterclockwise from the plane perpendicular to the straight line direction, like the second permanent magnet 11 (bb), but the second permanent magnet 11 ( Unlike bb), the S pole face is directed to one side (left side) and the N pole face is directed to the other side (right side).

  In such an arrangement, the first permanent magnet 11 (aa) and the second permanent magnet 11 (bb) have their one ends close to each other at the proximity point 32 between them, and the other end is the magnetic pole length L. The N pole faces are diagonally faced at an opening angle θ, separated from each other. Further, the third permanent magnet 11 (cc) and the last fourth permanent magnet 11 (dd) are also close to each other at the proximity point 32 between them, and the other end is separated by the magnetic pole length L. However, in this case, the S pole faces are diagonally faced with an open angle θ. At any proximity point 32, the proximity state is preferably close, but may be somewhat apart if magnetic flux leakage is negligible. Further, the second permanent magnet 11 (bb) and the third permanent magnet 11 (cc) face the S pole face and the N pole face obliquely. The short-circuiting yoke portion 12 is sandwiched between the S-pole surface of the second permanent magnet 11 (bb) and the N-pole surface of the third permanent magnet 11 (cc) and fits between both pole surfaces. Therefore, the magnetic flux over both pole surfaces is stored inside the yoke so as not to leak to the outside.

  The first magnetic pole yoke portion 13 (N) is formed in an isosceles triangle with a cross section that is sandwiched between the first permanent magnet 11 (aa) and the second permanent magnet 11 (bb) and fits between both magnets. The apex angle at the proximity point 32 is the same as the opening angle θ, the length of both sides sandwiching the apex angle is the same as the permanent magnet length W, and the opposite side (the lower side in FIG. 1B) ) Is the magnetic pole length L. The opposite side is an exposed surface in consideration of the depth, and serves as an N magnetic pole (field magnetic pole) from which the magnetic flux that has entered from the N pole surface of the adjacent permanent magnets 11 goes out. Further, the second magnetic pole yoke portion 13 (S) is sandwiched between the third permanent magnet 11 (cc) and the fourth permanent magnet 11 (dd) so as to have an isosceles cross section that fits between the two magnets. As in the first magnetic pole yoke portion 13 (N), the apex angle at the proximity point 32 is the same as the open angle θ, and the length of both sides sandwiching the apex angle is the permanent magnet length W. The length of the opposite side is the magnetic pole length L, but unlike the first magnetic pole yoke portion 13 (N), the opposite side is from the S pole surface of the permanent magnet 11 on both sides. It is an S magnetic pole (field magnetic pole) in which the incoming magnetic flux goes out.

  As a clear difference from the conventional product, the opening angle θ between the first permanent magnet 11 (aa) and the second permanent magnet 11 (bb) is an acute angle smaller than a right angle. The opening angle θ between (cc) and the fourth permanent magnet 11 (dd) is also an acute angle smaller than a right angle. Also, the length W from the end on the near side to the end on the remote side related to the first permanent magnet 11 (aa) and the end on the side remote from the end on the close side related to the second permanent magnet 11 (bb) The total length (W × 2) of the first permanent magnet 11 (aa) and the second permanent magnet with respect to the N magnetic pole of the first magnetic pole yoke portion 13 (N) 11 (bb) is 1.42 times or more of the magnetic pole length L extending to the end on the remote side. Further, the length W from the end on the close side related to the third permanent magnet 11 (cc) to the end on the remote side and the end on the remote side from the end on the close side related to the fourth permanent magnet 11 (dd) The total length (W × 2) with the length W of the third permanent magnet 11 (cc) and the fourth permanent magnet with respect to the S magnetic pole of the second magnetic pole yoke portion 13 (S) 11 (dd) is 1.42 times or more of the magnetic pole length L extending to the end on the remote side.

  Regarding the magnet body 30 of the first embodiment, the state of the magnetic circuit will be described with reference to the drawings. FIG. 1C is a magnetic flux distribution diagram according to a transverse plan view of the magnet body 30.

In the magnet body 30, the magnetic flux that has entered the first magnetic pole yoke portion 13 (N) from the N pole surface of the second permanent magnet 11 (bb) exits from the N magnetic pole surface of the magnetic pole yoke portion 13 to the outside. Then, it reaches the S magnetic pole surface of the right second magnetic pole yoke portion 13 (S), and enters the second magnetic pole yoke portion 13 (S) from there to the third permanent magnet 11 (cc). It enters from the pole surface, and then returns to the original place through the third permanent magnet 11 (cc), the short-circuiting yoke portion 12 and the second permanent magnet 11 (bb), and makes a round.
At that time, only the part of the path from the N magnetic pole to the S magnetic pole exits to the outside.

  In addition, the magnetic flux that has entered the first magnetic pole yoke portion 13 (N) from the N pole surface of the first permanent magnet 11 (aa) exits from the N magnetic pole surface of the magnetic pole yoke portion 13 to the left. And then return to the original place through a magnetic path of the same or appropriate manner as described above, and go around. Furthermore, the magnetic flux that has entered the second magnetic pole yoke portion 13 (S) from the S pole surface of the fourth permanent magnet 11 (dd) goes out of the S magnetic pole surface of the magnetic pole yoke portion 13 to the right, And then return to the original position through a magnetic path of the same or appropriate manner as described above, and this also makes a round.

  And in such a magnetic circuit, since the cross section of the yoke part 13 for magnetic poles is an isosceles triangle and the polarity of the magnetic flux which enters from both hypotenuses is the same, it came in from the hypotenuse on the left The magnetic flux turns downward and escapes from the left half of the base of the isosceles triangle, and the magnetic flux entering from the right hypotenuse turns downward and escapes from the right half of the base of the isosceles triangle. Therefore, the magnetic flux density of the permanent magnet 11 increases to (W × 2 / L) times the magnetic pole length ratio at the magnetic pole (field magnetic pole) of the magnetic pole yoke portion 13, but the permanent magnets 11 sandwiching the magnetic pole yoke portion 13 Since the opening angle θ is an acute angle, it increases to 1.42 times or more. For example, if the cross section of the magnetic pole yoke 13 is an equilateral triangle, the opening angle θ is 60 ° and the magnetic pole length ratio is 2. The magnetic flux density is also doubled.

  Further, inside the magnetic pole yoke portion 13, the magnetic flux distribution is almost uniform, the magnetic flux density is almost the same everywhere, and the respective portions are magnetized in the same manner, so that the yoke is used without waste for magnetization. That is, with respect to the magnetized state, it is unlikely that other portions of the yoke will be magnetically saturated while some of the yokes are hardly magnetized. The shape of the magnetic pole yoke portion 13 is preferably an equilateral triangle or an isosceles triangle in cross section from the viewpoint of not only the magnetic performance but also the ease of manufacture. Different triangles may be used, corners and corners may be chamfered, and the pole face may be bent if it is a little.

  A specific configuration of the magnet body according to the second embodiment of the present invention will be described with reference to the drawings. FIG. 2A is a cross-sectional plan view and an enlarged end view of the magnet body 40.

This magnet body 40 is different from the magnet body 30 of the first embodiment described above in that the magnet body 30 is repeatedly arranged in a straight line direction (one-line direction, adjacent arrangement direction, left-right direction in the drawing) and becomes a long product. And the end member 41 is arrange | positioned at both ends, respectively, and it is the point which became the end magnet body.
Since the intermediate part of the magnet body 40 is the same as the magnet body 30 mentioned above, the repeated description is omitted. Since the left end portion of the magnet body 40 has the same structure as the right end portion when viewed from the back, the description of the left end portion will be omitted and the structure of the right end portion of the magnet body 40 will be described below.

  The right end portion of the magnet body 40 is different from the magnet body 30 described above in that a flat end member 41 (dd) made of a non-magnetic material is introduced instead of the fourth permanent magnet 11 (dd); The point in which the direction of the end member 41 is in a state orthogonal to the straight line direction, and accordingly, the cross-sectional shape of the second magnetic pole yoke portion 13 (S) is a left-right angle obtained by vertically dividing an isosceles triangle. It is a point that is a triangle. In the magnet body 40, the third permanent magnet 11 (cc) and the end member 41 (dd) are the proximity points 32 between the third permanent magnet 11 (cc) and the fourth permanent magnet 11 (dd). Both end portions are close to each other, the other end portion is separated by a magnetic pole length M = L / 2, and the S pole surface and the non-magnetized surface are obliquely faced at an opening angle φ = θ / 2. ing.

  Further, the second magnetic pole yoke portion 13 (S) which has been in a half-cracked state is sandwiched between the S pole surface of the third permanent magnet 11 (cc) and the non-magnetized surface of the end member 41 (dd). It is formed in a right-angled triangular cross section that fits in between, the apex angle at the proximity point is the same as the opening angle φ = θ / 2 and less than half the right angle, the length of the opposite side (bottom side in the figure) Is the magnetic pole length M, but this opposite side is an S magnetic pole (field magnetic pole) from which the magnetic flux entering from the S pole surface of the third permanent magnet 11 (cc) goes out. Furthermore, since the magnetic pole length M is half of the magnetic pole length L, the end on the far side from the end on the close side related to the third permanent magnet 11 (cc), which is a permanent magnet closer to the end member 41 (dd), is provided. The end W on the remote side of the permanent magnet 11 and the remote side of the end member 41 with respect to the S magnetic pole of the second magnetic pole yoke 13 (S) adjacent to the end member 41 (dd) It is 1.42 times or more of the magnetic pole length M extending to the end of each.

Regarding the magnet body 40 of the second embodiment, the state of the magnetic circuit will be described with reference to the drawings. FIG. 2B is a magnetic flux distribution diagram according to a transverse plan view and an enlarged end view of the magnet body 40.
In this case, the magnetic flux emitted from the S magnetic pole of the second magnetic pole yoke portion 13 (S) to the outside is prevented from being expanded rightward by the right end member 41 (dd).

  Therefore, the detailed description which will be repeated will be omitted, but as with the magnetic circuit of the magnet body 30, the magnetic flux emitted to the outside from the N pole surface of the first magnetic pole yoke portion 13 (N) is the second on the right side. It reaches the S magnetic pole surface of the magnetic pole yoke portion 13 (S), enters the second magnetic pole yoke portion 13 (S) from there, enters the third permanent magnet 11 (cc), the short-circuited yoke portion 12 and the second magnetic pole portion 13 (S). It goes around through the permanent magnet 11 (bb) and the first magnetic pole yoke 13 (N). Moreover, since the magnetic flux distribution state in the second magnetic pole yoke portion 13 (S) is a mirror image of the first magnetic pole yoke portion 13 (N), the second magnetic pole yoke portion 13 (S). As with the first magnetic pole yoke portion 13 (N), the magnetic flux density of the magnetic pole (field magnetic pole) is increased by 1.42 times or more compared to the magnetic flux density of the permanent magnet 11.

  A specific configuration of the magnet body according to the third embodiment of the present invention will be described with reference to the drawings. 3A is a front view of the magnet body 50, and FIG. 3B is a transverse plan view.

  This magnet body 50 is different from the magnet body 40 of the second embodiment described above in that the first permanent magnet 11 (aa) is replaced with a flat end member 41 (aa) made of a non-magnetic material. It is a point. Similar to the right end member 41 (dd), the left end member 41 is in a state in which the direction is orthogonal to the straight line direction. Further, the first magnetic pole yoke portion 13 (N) is substantially the same as the second magnetic pole yoke portion 13 (S), but it is in a mirror image state, and the right cross-section is an isosceles triangle divided into two vertically. It is a right triangle. And in this magnet body 50, while the 2nd permanent magnet 11 (bb) was the proximity point 32 with the 1st permanent magnet 11 (aa), while making the end member 41 (aa) and one end part adjoin, other The ends are separated by the magnetic pole length M = L / 2, and the S pole surface is obliquely opposed to the non-magnetized surface at an opening angle φ = θ / 2.

  Further, the first magnetic pole yoke portion 13 (N) that has been split into pieces is sandwiched between the N pole surface of the second permanent magnet 11 (bb) and the non-magnetized surface of the end member 41 (aa). It is formed in a right-angled triangular cross section that fits in between, the apex angle at the proximity point is the same as the opening angle φ = θ / 2 and less than half the right angle, the length of the opposite side (bottom side in the figure) Is the magnetic pole length M, but this opposite side is an N magnetic pole (field magnetic pole) from which the magnetic flux entering from the N pole surface of the second permanent magnet 11 (bb) goes out. Furthermore, since the magnetic pole length M is half of the magnetic pole length L, the end on the remote side from the end on the near side related to the second permanent magnet 11 (bb) which is the permanent magnet closer to the end member 41 (aa). The end W on the separation side of the permanent magnet 11 and the separation side of the end member 41 with respect to the N magnetic pole of the first magnetic pole yoke portion 13 (N) adjacent to the end member 41 (aa). It is 1.42 times or more of the magnetic pole length M extending to the end of each.

  Regarding the magnet body 50 of the third embodiment, the state of the magnetic circuit will be described with reference to the drawings. FIG. 3C is a magnetic flux distribution diagram according to a cross-sectional plan view of the magnet body 50.

  The magnet body 50 is the limit that allows the magnet body 40 to be scraped from the left and shortened to the shortest. In this case, the second magnetic pole as described above is applied to the right end portion that inherits the structure of the magnet body 40 as it is in the right half. The magnetic flux that has flowed outside from the S magnetic pole of the yoke portion 13 (S) is prevented from expanding to the right by the right end member 41 (dd), and the end member 41 (aa) is introduced. With respect to the left end portion, the magnetic flux that has flowed out from the N magnetic pole of the first magnetic pole yoke portion 13 (N) is prevented from being expanded to the left by the left end member 41 (aa). The

  For this reason, as in the magnetic circuit of the magnet bodies 30 and 40 described above, the magnetic flux that has flowed to the outside from the N pole surface of the first magnetic pole yoke portion 13 (N) is also transferred to the right second magnetic pole yoke. To the S magnetic pole surface of the portion 13 (S), from which it enters the second magnetic pole yoke portion 13 (S), the third permanent magnet 11 (cc), the short-circuiting yoke portion 12 and the second permanent magnet 11 ( bb) and the first magnetic pole yoke 13 (N) make a round. Further, since the magnetic flux distribution state in the left first magnetic pole yoke portion 13 (N) is the mirror image of the right second magnetic pole yoke portion 13 (S) described above, Similarly to the yoke portion 13 (S) for the second magnetic pole, the magnetic flux density of the magnetic pole (field magnetic pole) is increased 1.42 times or more compared to the magnetic flux density of the permanent magnet 11 in the yoke portion 13 (N).

A specific configuration of the magnet body according to the fourth embodiment of the present invention will be described with reference to the drawings. FIG. 4 is a cross-sectional plan view and an enlarged end view of the magnet body 60.
In this magnet body 60, an end member 61, a closing unit 62 (forward), a closing unit 62 (reverse), and an end member 61 are arranged adjacently in a straight line (one line) in this order from left to right. Each of the end members 61 is provided for the end of the magnet body 60 similarly to the above-described end member 41, is made of a flat nonmagnetic material, and is arranged in a state orthogonal to the straight line direction. Has been.

Since the circuit closing unit 62 (forward) and the circuit closing unit 62 (reverse) have the same structure and the difference is that they are simply reversed left and right during the arrangement, in the following description of the structure, the circuit closing unit 62 (normal) Will be described.
The circuit closing unit 62 is different from the magnet body 30 of the first embodiment described above in that a bypass yoke portion 63 is attached to a portion corresponding to the magnet body 30 from the back side. Since the back side is the least magnetically and mechanically interfering with the N and S magnetic poles, it is suitable for mounting the bypass yoke 63. However, if the interference is within an allowable range, the magnet body The bypass yoke portion 63 may be attached to the 30 equivalent portion from another direction such as an upper side, a lower side, or an oblique direction.

  The bypass yoke portion 63 is an integral body made of a ferromagnetic material, and includes a rearward bypass intermediate portion 64, a left bypass end portion 65, a central direct short-circuit portion 66, and a right bypass end portion 65. It has. Among them, the direct short-circuit portion 66 has the same shape as the short-circuiting yoke portion 12 and is sandwiched between the second permanent magnet 11 (bb) and the third permanent magnet 11 (cc). The detour end portion 65 on the left side has the same shape as the right side crack obtained by dividing the short-circuiting yoke portion 12 into left and right parts, and is arranged adjacent to the first permanent magnet 11 (aa) from the left side. The adjacent arrangement of the shape extends to the left. The detour end 65 on the right side has the same shape as the left side crack obtained by dividing the short-circuiting yoke portion 12 into left and right parts, and is arranged adjacent to the fourth permanent magnet 11 (dd) from the right side. The adjacent arrangement of the shape extends to the right. The detour intermediate part 64 is long on the left and right, and connects the above-described parts 65, 66, 65 on the back side. In addition, although the direct short circuit part 66 is integrated here, you may divide | segment and make it a separate body, and it will become the short-circuiting yoke part 12 in the magnet body 30 mentioned above.

  Regarding the magnet body 60 of the fourth embodiment, the state of the magnetic circuit will be described with reference to the drawings. FIG. 5 is a magnetic flux distribution diagram according to a cross-sectional plan view and an enlarged end view of the magnet body 60.

  Since the circuit unit 62 (forward) and the circuit unit 62 (reverse) are also reversed in the state of the magnetic circuit, the state of the magnetic circuit related to the circuit unit 62 (forward) will be described in detail (see the enlarged end view). ), The magnetic flux that has entered the first magnetic pole yoke 13 (N) from the N pole surface of the second permanent magnet 11 (bb) exits from the right half of the N magnetic pole surface of the magnetic pole yoke 13 to the outside. Thus, it reaches the left half of the S magnetic pole surface of the right second magnetic pole yoke portion 13 (S), and enters the second magnetic pole yoke portion 13 (S) from there to enter the third permanent magnet 11 (cc). From the S pole surface, and then returns to the original position through the third permanent magnet 11 (cc), the direct short-circuit portion 66 corresponding to the short-circuiting yoke portion 12 and the second permanent magnet 11 (bb). Go round. At that time, only the part of the path from the N magnetic pole to the S magnetic pole exits to the outside. The one-round magnetic path is the same as that described above for the magnet body 30.

  On the other hand, the magnetic flux that has entered the first magnetic pole yoke portion 13 (N) from the N pole surface of the first permanent magnet 11 (aa) exits from the N magnetic pole surface of the magnetic pole yoke portion 13 to the outside. Therefore, it passes through a magnetic path different from that of the magnet body 30 described above. That is, the magnetic flux that has flowed out of the left half of the N magnetic pole face also goes to the right instead of to the left, and reaches the right half of the S magnetic pole face of the right second yoke portion 13 (S). From there, it enters the second magnetic pole yoke 13 (S). Then, the fourth permanent magnet 11 (dd) enters from the S pole face thereof, the fourth permanent magnet 11 (dd), the right detour end portion 65, the rear detour intermediate portion 64, and the left detour end portion 65. And return to the original position through the inside of the first permanent magnet 11 (aa) and make a round. At this time as well, only the part of the path from the N magnetic pole to the S magnetic pole goes out to the outside, but the circuit that makes a round follows the outside of the same path as the magnet body 30 described above.

  In this way, the left and right bypass end portions 65 both contain the magnetic flux coming from the adjacent permanent magnet 11 and guide it to the bypass intermediate portion 64, and the first magnetic pole yoke portion 13 (N) N The detour intermediate portion 64 disposed on the back side, which is different from the position of the magnetic pole and the position of the S magnetic pole of the second magnetic pole yoke portion 13 (S), accommodates the magnetic flux coming from the detour end portion 65 in the inside thereof. Since the N magnetic pole of the first magnetic pole yoke portion 13 (N) and the S magnetic pole of the second magnetic pole yoke portion 13 (S) are bypassed, the first magnetic pole yoke portion 13 (N) Most of the magnetic flux emitted from the N magnetic pole reaches the S magnetic pole of the second magnetic pole yoke portion 13 (S). Moreover, since the magnetic flux density of each magnetic pole (field magnetic pole) is higher than that of the conventional magnet body 30 as in the case of the magnet body 30, the magnetic flux reaches farther than before from the magnetic pole surface.

  When a long magnetic body is formed by connecting a plurality of closed circuit units 62 in one direction, the closed circuit units 62 (forward) and the closed circuit units 62 (reverse) are alternately arranged as in the magnet body 60, so that Since magnetic interference from the unit is prevented, a magnet body having an arbitrary length can be easily formed, and since it can be easily replaced in units of the closed circuit unit 62, repair and maintenance are easy to perform. Moreover, although the shape and arrangement of the permanent magnet 11 are the same as those of the magnet bodies 30 and 40, the sizes and pitches of the N magnetic pole and the S magnetic pole are twice that of the magnet bodies 30 and 40, and the reach of the magnetic flux to the outside is also the magnet body. More than that of 30,40.

  A specific configuration of the magnet body according to the fifth embodiment of the present invention will be described with reference to the drawings. FIG. 6A is a cross-sectional plan view of the main part of a linear motor 40 + 70 using the magnet body 40 of the second embodiment described above as a mover.

This linear motor 40 + 70 is provided with a stator 70 in addition to the magnet body 40 of the end mover. The magnet body 40 and the stator 70 are separated from the train and the railroad track in a parallel state and a parallel running state. The magnetic pole faces are opposed to each other with a predetermined separation distance.
In this linear motor 40 + 70, the magnet body 40 is mounted on the train as a permanent magnet field, and the stator 70 is laid on the track as an armature, but the reverse is also possible. Although both the magnet body 40 and the stator 70 are arranged in a line as necessary, only one magnet body 30 serving as a repetitive basic unit is illustrated. Further, the pole pitch τ in the magnet body 40 is shown by the distance between the proximity points 32 and 32 corresponding to the center positions of the N magnetic pole and the S magnetic pole, respectively.

  The stator 70 is a long prismatic shape in which a U-phase coil, a V-phase coil, and a W-phase coil driven by a three-phase current are repeatedly arranged in that order in an adjacent state, and a rectangular shape having a width J × depth D is taken as a cross-sectional shape. It is inserted into the ferromagnetic material. The length of the U-phase coil, V-phase coil, and W-phase coil connected to each other is the same as the length of the magnet body 30, the depth D of each coil is the same as that of the magnet body 40 (30), and the coil cross section is vertical. E × width F rectangle. The coil insertion surface of the stator 70 and the magnetic pole surface of the magnet body 40 (30) face each other across an air gap having a gap length G.

  Regarding the linear motor 40 + 70 of the fifth embodiment, the state of the magnetic circuit will be described with reference to the drawings. FIG. 6B is a magnetic flux distribution diagram according to a cross-sectional plan view of the linear motor 40 + 70. A portion of the magnet body 40 (30) from the first permanent magnet 11 (aa) to the fourth permanent magnet 11 (dd), and a portion of the stator 70 in which a U-phase coil, a V-phase coil, and a W-phase coil are connected; Is the time when the propulsive force is at the maximum, but even in this state, the difference in density and the difference in density produced in the magnetic flux distribution in the magnetic pole yoke portion 13 of the magnet body 40 (30). That is, since the magnetic flux disturbance is small, the whole area of the magnetic pole yoke portion 13 is moderately magnetized and contributes to the generation of thrust without waste.

  As a numerical example, the holding force Hc of the permanent magnet 11 is 915 kA / m, the JFE50JN800 is used for the yoke, the gap length G is 12 mm, the magnetic pole length L is 160 mm, the pole pitch τ is 240 mm, and the permanent magnet When the length W is 160 mm, the permanent magnet thickness H is 30 mm, and the depth D is 200 mm, the air gap magnetic flux density is about 1.15T. Further, when the permanent magnet length W is changed to 300 mm from there, the air gap magnetic flux density becomes about 1.6T. Further, when the permanent magnet thickness H is changed from that to 40 mm, the air gap magnetic flux density becomes about 1.8T. These air gap magnetic flux densities are about the same as or exceeding the residual magnetic flux density of the rare earth permanent magnet of about 1.15 T, and the air gap magnetic flux density in a conventional motor (for example, paragraphs 0027 and FIG. 9 shows that when the residual magnetic flux density of the permanent magnet is 1.1 to 15T, the maximum value of the air gap magnetic flux density is considerably larger than about 0.7T). A gap length G of 12 mm is suitable for railway applications.

  Furthermore, when the yoke width J of the stator 70 is 100 mm, the longitudinal E of the cross section of each coil of the stator 70 is 60 mm, the lateral F is 30 mm, the number of turns of each phase coil is 60 times, and a current 30A is passed, The maximum thrust is as large as 1680N per pole, and the attractive force is 30989N (3160kg weight), which far exceeds the weight of the magnet body 40 with a mass of 117kg. Therefore, it is impossible to use a linear motor car with the magnet body 40 mounted on the train. Can be realized.

[Others]
In the above embodiment, the opening angle of the magnetic pole yoke portion and the opening angle of the short-circuiting yoke portion are the same, and the adjacent arrangement of the permanent magnet and the yoke portion is in a straight line. The adjacent arrangement with the portion may be curved, and can be easily bent by making a difference between the opening angle of the magnetic pole yoke portion and the opening angle of the short-circuiting yoke portion, for example.
In the above embodiment, not only the series of the permanent magnet and the yoke part but also the series of the N magnetic pole and the S magnetic pole are in a straight line shape, but both of them may be curved, and only one of them is a straight line. And the other may be curved. For example, when the connection between the permanent magnet and the yoke portion is linear and the connection between the N magnetic pole and the S magnetic pole is spiral, it is suitable for driving an advertising display cylinder that moves up and down while rotating the shaft. is there.

  The magnet body of the present invention was developed mainly for the purpose of contributing to high performance of railway linear motors, but its application is not limited to linear motors and is also used in the railway field. The present invention can also be applied to other things such as a magnetic treadle that is used and driving of a lifting member used in other fields as described above.

  The magnetic treadle (see Hiroshi Yoshimura and Saburo Yoshikoshi, “Signal” 17th edition, pages 490 to 491) is also called a magnetic impulse generator, which is a secondary magnet that generates a magnetic flux in the opposite direction to the main pole (both permanent Magnet) and a polarized relay in the range of the synthesized magnetic flux. Normally, the polarized relay operates in a certain direction by the main pole, but when the train axle enters, its flange (ring) Thus, the main magnetic pole is shunted, the magnetic flux of the main magnetic pole branched to the relay is weakened, and the polarized relay is reversed by the magnetic flux of the sub magnetic pole in the opposite direction to open and close the electrical contact. When the axle moves away from the operating range, the magnetic relation between the main magnetic pole and the sub magnetic pole is restored, so that the contacts of the polarized relay are restored to the current state and restored.

  By installing a magnetic treadle on the side of the rail that the train travels, it is possible to detect the departure of the train. Since the magnetic treadle operates the relay by utilizing the change of the magnetic field when the train axle (wheel) passes as described above, the amount of change in the magnetic field can be reduced by incorporating the magnet body of the present invention. Since it becomes large, the distance from the rail can be increased, and the detection amount is large, so that detection is easy.

10: Rotor (endless mover, magnet body),
11 ... Permanent magnet, 12 ... Short circuit yoke (yoke),
13 ... yoke part for magnetic pole (yoke), 20 ... rotor (endless mover, magnet body),
30 ... Magnet body, 31 ... Holding member, 32 ... Proximity point,
40 ... magnet body, 41 ... end member, 50 ... magnet body, 60 ... magnet body,
61 ... End member, 62 ... Closing unit, 63 ... Detour yoke (yoke),
64 ... Detour intermediate section, 65 ... Detour end section, 66 ... Direct short circuit section, 70 ... Stator,
θ, φ ... open angle, L, M ... magnetic pole length, W ... permanent magnet length

Claims (5)

  A flat plate-shaped first permanent magnet magnetized in the thickness direction, a first magnetic pole yoke made of a ferromagnetic material, a flat plate-shaped second permanent magnet magnetized in the thickness direction, and a short circuit made of a ferromagnetic material. A yoke part, a plate-shaped third permanent magnet magnetized in the thickness direction, a second magnetic pole yoke part made of a ferromagnetic material, and a plate-shaped fourth permanent magnet magnetized in the thickness direction. In this order, the first permanent magnet and the second permanent magnet are arranged adjacent to each other in a line, and the N pole faces are obliquely facing each other with one end portion approached and the other end portion separated. The first magnetic pole yoke portion is an N magnetic pole that emits a magnetic flux to the outside in a state of being loaded between both N pole surfaces, and the third permanent magnet and the fourth permanent magnet are close to one end. And the other end portions are separated from each other so that the S pole faces face each other obliquely, and the second pole is mounted between the two S pole faces. The iron part is an S magnetic pole that emits a magnetic flux to the outside, and the short-circuiting yoke part is loaded between the S pole face of the second permanent magnet and the N pole face of the third permanent magnet. In the magnet body configured to contain the magnetic flux, the opening angle between the first permanent magnet and the second permanent magnet and the opening angle between the third permanent magnet and the fourth permanent magnet are both acute angles. A magnet body characterized by being formed.   A flat plate-shaped first permanent magnet magnetized in the thickness direction, a first magnetic pole yoke made of a ferromagnetic material, a flat plate-shaped second permanent magnet magnetized in the thickness direction, and a short circuit made of a ferromagnetic material. A yoke part, a plate-shaped third permanent magnet magnetized in the thickness direction, a second magnetic pole yoke part made of a ferromagnetic material, and a plate-shaped fourth permanent magnet magnetized in the thickness direction. In this order, the first permanent magnet and the second permanent magnet are arranged adjacent to each other in a line, and the N pole faces are obliquely facing each other with one end portion approached and the other end portion separated. The first magnetic pole yoke portion is an N magnetic pole that emits a magnetic flux to the outside in a state of being loaded between both N pole surfaces, and the third permanent magnet and the fourth permanent magnet are close to one end. And the other end portions are separated from each other so that the S pole faces face each other obliquely, and the second pole is mounted between the two S pole faces. The iron part is an S magnetic pole that emits a magnetic flux to the outside, and the short-circuiting yoke part is loaded between the S pole face of the second permanent magnet and the N pole face of the third permanent magnet. In the magnet body configured to contain the magnetic flux, the length from the end portion on the near side to the end portion on the separation side related to the first permanent magnet and the distance from the end portion on the near side related to the second permanent magnet are separated. The total length of the first magnetic pole yoke portion and the second permanent magnet remote end portion with respect to the N magnetic pole of the first magnetic pole yoke portion And the length from the proximal end to the remote end of the third permanent magnet and the proximal end of the fourth permanent magnet The total length of the third permanent magnet with respect to the S magnetic pole of the second magnetic pole yoke portion is the total length from the portion to the end on the remote side. Magnet body, characterized spaced side end portion and the fourth is equal to or greater than 1.42 times the pole length over the separation end of the permanent magnet, that.   An end member made of a nonmagnetic material is provided instead of one or both of the first permanent magnet and the fourth permanent magnet, and the end member is close to the end member of the second permanent magnet and the third permanent magnet. 2. The magnet body according to claim 1, wherein an opening angle between the end member and the end member is less than half of a right angle.   An end member made of a nonmagnetic material is provided instead of one or both of the first permanent magnet and the fourth permanent magnet, and the end member is close to the end member of the second permanent magnet and the third permanent magnet. The length from the proximal end to the remote end of the permanent magnet is longer than either the first magnetic pole yoke portion or the second magnetic pole yoke portion. The magnetic pole length of the magnetic pole adjacent to the magnetic pole is 1.42 times or more the length of the magnetic pole extending between the end on the remote side of the permanent magnet and the end on the remote side of the end member. 2. The magnet body according to 2.   A bypass yoke portion is provided in which a bypass intermediate portion made of a ferromagnetic material and a bypass end portion are connected, and the bypass end portion is provided on one or both of the first permanent magnet and the fourth permanent magnet. The one-line adjacent arrangement is extended adjacently, and the magnetic flux coming from the adjacent permanent magnet is contained inside and guided to the detour intermediate section, and the detour intermediate section Is arranged at a location different from the N magnetic pole and the S magnetic pole, and the magnetic flux coming from the detour end portion is accommodated inside to bypass the N magnetic pole and the S magnetic pole. The magnet body according to claim 1 or 2.

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