JP6826525B2 - Linear motor - Google Patents

Description

The present invention relates to a linear motor including a magnetic pole having a permanent magnet and an iron core.

Patent Document 1 discloses a linear motor having a columnar magnetic monopole and a cylindrical armature arranged so as to surround the outer periphery of the magnetic monopole. In this linear motor, a plurality of coils are provided side by side in the circumferential direction in the armature, and the same number of permanent magnets as the coils are provided side by side in the circumferential direction in the magnetic pole. Each permanent magnet is arranged so that one magnetic pole surface faces the coil, and the magnetic poles of adjacent permanent magnets have opposite polarities.

Patent Document 2 discloses a linear motor having magnetic poles in which permanent magnets are arranged in a Halbach array. In the Halbach array, a large amount of magnetic flux can be interlinked in the coil without using an iron core, and a lightweight, high-power linear motor can be obtained.

Special Table 2014-504129 Japanese Patent No. 5404029

In an electric motor, there are the following two methods for increasing the thrust per volume.
(1) Increase the area of the thrust generating surface, that is, the surface facing the magnetic monopole and the armature.
(2) By increasing the size of the coil, the magnetic flux generated from the armature is increased.
However, in the linear motor disclosed in Patent Document 1, if the radius of the magnetic pole element is increased in order to increase the thrust generation surface, the space (coil space) in which the armature coil is provided is reduced, and the coil is miniaturized. It ends up. Although the coil space can be increased by making the back yoke of the armature thinner, magnetic saturation occurs in the back yoke and the thrust characteristics deteriorate. On the other hand, the Halbach array is a method of increasing the magnetic flux density in the void by increasing the amount of magnets in the magnetic path, and the amount of magnets increases, resulting in high cost.

The present invention has been made in view of such circumstances, and a main object thereof is to provide a linear motor that can solve the above problems.

In order to solve the above-mentioned problems, the linear motion motor according to one aspect of the present invention includes a columnar magnet in which a plurality of coils are arranged side by side in the circumferential direction, and a magnetic pole magnet surrounding the magnet. The magnetic pole element has a plurality of magnetic pole blocks including an iron core arranged so as to face the coil and a plurality of permanent magnets that open the surface facing the coil and surround the iron core. In, the plurality of permanent magnets are arranged so that the same magnetic poles are directed toward the iron core, and each of the plurality of the magnetic pole blocks is arranged so that different magnetic poles are arranged alternately in the circumferential direction, and the different magnetic poles are arranged. Arranged so as to be alternately arranged in the longitudinal direction of the magnet, the magnetic flux emitted from the open side surface of the one magnetic pole block branches in the circumferential direction and the longitudinal direction to and the magnetic pole block of the one. It enters the other magnetic pole blocks adjacent to each other in the circumferential direction and the longitudinal direction .

Further, in the above aspect, the adjacent magnetic pole blocks may have one surface of the permanent magnet in close contact with each other.

Further, in the above aspect, the iron core has two fan-shaped circular fan-shaped surfaces having a missing tip in the longitudinal direction of the magnet and four side surfaces perpendicular to the two annular fan-shaped surfaces. The magnetic pole block may be formed by attaching the permanent magnet to each of the five surfaces other than the radial inner side surface of the fan shape in the iron core.

Further, in the above aspect, the iron core has a polyhedron shape having two trapezoidal surfaces parallel to each other in the longitudinal direction of the armature and four side surfaces perpendicular to the two trapezoidal surfaces. The magnetic pole block may be configured such that the permanent magnet is attached to each of the five surfaces of the iron core other than the side surface on the upper bottom side of the trapezoid.

Further, in the above aspect, the iron core has two main surfaces parallel to each other having a pentagonal arcuate side in the longitudinal direction of the armature, and five perpendicular to the two main surfaces. The magnetic pole block has a three-dimensional shape having a side surface, and the magnetic pole block may be configured by attaching the permanent magnet to each of six surfaces other than the arcuate side surface of the iron core.

Further, in the above embodiment, the iron core is a hexahedron having two faces of rhombuses parallel to each other and four faces perpendicular to the two faces, centered on an axis parallel to one diagonal of the rhombus. In addition, the magnetic pole block has a three-dimensional shape in which other diagonal lines are curved in an arc shape, and the magnetic pole block is configured by attaching the permanent magnet to each of five surfaces other than the arc surface on the inner side in the radial direction of the iron core. May be good.

Further, in the above aspect, the magnetic monopole may be formed in an annular shape in which a part is missing in order to attach an object for transmitting thrust.

According to the present invention, it is possible to improve the thrust characteristics of the linear motor as compared with the conventional case while suppressing the cost.

The perspective view which shows the structure of the linear electric motor which concerns on Embodiment 1. FIG. FIG. 5 is a plan sectional view showing a configuration of an armature according to the first embodiment. The perspective view which shows the structure of the magnetic pole element which concerns on Embodiment 1. FIG. The exploded perspective view which shows the structure of the magnetic pole block which concerns on Embodiment 1. FIG. A partially enlarged plan sectional view for explaining a magnetic path of a magnetic pole element according to the first embodiment. FIG. 5 is a cross-sectional view taken along the line AA of FIG. FIG. 3 is a partially enlarged plan sectional view showing a magnetic path generated from the armature coil according to the first embodiment. The plan view which shows the structure of the linear electric motor which concerns on Embodiment 2. The plan view which shows the structure of the rack and pinion mechanism using the linear electric motor which concerns on Embodiment 2. FIG. The side view which shows the structure of the rack and pinion mechanism which used the linear motor which concerns on Embodiment 2. FIG. The perspective view which shows the structure of the armature which concerns on Embodiment 3. The perspective view which shows the structure of the magnetic pole element which concerns on Embodiment 3. The plan view which shows the structure of the armature which concerns on Embodiment 3. FIG. 13 is a view taken along the line BB of FIG. An exploded perspective view showing a configuration of a magnetic pole block according to a third embodiment. The figure which shows the state which developed the inner side surface of the magnetic pole element which concerns on Embodiment 3 in a plane. The plan sectional view which shows the structure of the magnetic pole element which concerns on Embodiment 4. FIG. An exploded perspective view showing a configuration of a magnetic pole block according to a fourth embodiment. FIG. 5 is a plan sectional view showing a configuration of a magnetic pole element according to a fifth embodiment. An exploded perspective view showing a configuration of a magnetic pole block according to a fifth embodiment. The plan sectional view which shows the modification of the structure of the magnetic pole child.

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

(Embodiment 1)
In the present embodiment, a linear motor including a columnar armature in which a plurality of coils are arranged side by side in the circumferential direction and an annular magnetic pole element surrounding the armature will be described. The magnetic pole element is configured by arranging a plurality of magnetic pole blocks in an annular shape so that different magnetic poles are arranged alternately in the circumferential direction.

FIG. 1 is a perspective view showing a configuration of a linear motor according to the present embodiment. The linear motor 100 includes a columnar armature 110 and an annular magnetic pole 120. The armature 110 and the magnetic pole 120 are arranged concentrically, and the magnetic pole 120 surrounds the armature 110. When the linear motor 100 is driven, the armature 110 and the magnetic pole 120 move relatively linearly. Here, the magnetic pole 120 may be a mover and the armature 110 may be a stator, or the armature 110 may be a mover and the magnetic pole 120 may be a stator. In the present embodiment, a configuration in which the magnetic pole 120 is a mover and the armature 110 is a stator will be described. In the following description, the longitudinal direction of the central axis 101 of the armature 110 is the "movable direction", the circumferential direction around the central axis 101 is the "circumferential direction", and the direction orthogonal to the central axis 101 is the "radial direction". ".

The configuration of the armature 110 will be described with reference to FIG. FIG. 2 is a plan sectional view showing the configuration of the armature. The armature 110 has an armature coil 111, a teeth portion 112, and a yoke portion 113. The yoke portion 113 has a cylindrical shape, and T-shaped tooth portions 112 project outward in the radial direction so as to be arranged at equal intervals in the circumferential direction in a plan view from the outer surface thereof. The teeth portions 112 are also provided side by side from the yoke portions 113 in the axial direction.

The yoke portion 113 and the teeth portion 112 are integrally formed as an armature member 115. The armature member 115 is made of a soft magnetic material such as soft iron or soft ferrite. Further, a conducting wire is wound around each tooth portion 112 to form an armature coil 111. Ten armature coils 111 are provided in the circumferential direction.

Next, the configuration of the magnetic monopole 120 will be described. As shown in FIG. 1, the magnetic pole elements 120 have an annular shape and are arranged on the outer side in the radial direction of the armature 110. FIG. 3 is a perspective view showing the configuration of the magnetic monopole 120. The magnetic pole element 120 has a plurality of magnetic pole blocks 121, and has a structure in which these magnetic pole blocks 121 are arranged in the circumferential direction.

FIG. 4 is an exploded perspective view showing the configuration of the magnetic pole block 121. The magnetic pole block 121 has a soft magnetic iron core 122 and five plate-shaped permanent magnets 123a to 123e. The iron core 122 has two planes (hereinafter referred to as "circular fan-shaped planes") parallel to each other in a fan shape (hereinafter referred to as "circular fan shape") whose tip is missing in an arc shape in the axial direction, and these circular rings. It has a three-dimensional shape with four sides perpendicular to the fan-shaped surface. The permanent magnets 123a and 123b have an annular fan-shaped main surface that is the same as or slightly larger than the annular fan-shaped surface of the iron core 122, and are attached to each of them so as to hide the annular fan-shaped surface of the iron core 122. The permanent magnets 123c and 123d have a width equal to or slightly larger than the axial length of the iron core 122, and are attached to each so as to hide the rectangular side surface (that is, the side surface parallel to the radial direction) of the iron core 122. Further, the permanent magnet 123e has an arc plate shape having the same outer diameter as the larger arc surface of the iron core 122, that is, the outer arc surface, and is attached to the permanent magnet 123e so as to hide the outer arc surface of the iron core 122. That is, permanent magnets 123a to 123e are attached to the iron core 122 so as to open and surround the inner arc surface. Further, the permanent magnets 123a to 123e are arranged so that the same magnetic poles are directed to the iron core 122. The open inner arc surface of the iron core 122 serves as a mover magnetic pole 124. As will be described later, the movable element magnetic pole 124 has the same magnetic pole as the magnetic pole on the surface where the permanent magnets 123a to 123e face the iron core 122. Further, the surface of each of the permanent magnets 123a to 123e facing outward (the surface opposite to the iron core 122) is the opposite magnetic pole of the mover magnetic pole 124.

See FIG. Each of the magnetic pole blocks 121 touches the side surfaces of the rectangle and is connected to each other in the circumferential direction. The mover magnetic poles 124 of the two magnetic pole blocks 121 adjacent to each other in the circumferential direction are different magnetic poles. That is, the magnetic pole blocks 121 are arranged in the circumferential direction so that the different movable magnetic poles 124 are arranged alternately. Therefore, one of the joint surfaces of the magnetic pole blocks 121 adjacent to each other in the circumferential direction has an S pole and the other has an N pole. Therefore, the two adjacent magnetic pole blocks 121 are attracted to each other by the magnetic force, and the plurality of magnetic pole blocks 121 can be easily arranged side by side in the circumferential direction.

Further, a plurality of annular structures in which a plurality of magnetic pole blocks 121 are arranged in a row are laminated in the axial direction. Each of the magnetic pole blocks 121 adjacent to each other in the axial direction are in contact with each other and are connected to each other. The mover magnetic poles 124 of the two magnetic pole blocks 121 adjacent to each other in the axial direction are different magnetic poles from each other. That is, the magnetic pole blocks 121 are arranged in the axial direction so that the different movable magnetic poles 124 are arranged alternately. Therefore, one of the joint surfaces of the magnetic pole blocks 121 adjacent to each other in the axial direction has an S pole and the other has an N pole. Therefore, the two adjacent magnetic pole blocks 121 are attracted to each other by the magnetic force, and the plurality of magnetic pole blocks 121 can be easily arranged side by side in the axial direction.

Further, a back yoke 125 made of a cylindrical soft magnetic material is arranged on the outside so as to surround the laminated annular structure. Therefore, in each magnetic pole block 121, magnetic poles other than the mover magnetic pole 124 are not exposed to the outside, and a magnetic path is formed in the back yoke 125.

FIG. 5 is a partially enlarged plan sectional view for explaining the magnetic path of the magnetic pole element 120, and FIG. 6 is a sectional view taken along the line AA of FIG. In FIGS. 5 and 6, the arrow indicates the magnetization direction, and the polarity is S → N. The iron core 122 is magnetized by the permanent magnets 123a to 123e surrounding the iron core 122. The magnetic flux generated from the permanent magnets 123a to 123e whose S pole faces the iron core 122 travels in the iron core 122. Since the permanent magnets 123a to 123e are attached to the five surfaces of the iron core 122, the magnetic fluxes emitted from each of the five permanent magnets 123a to 123e travel inside the iron core 122, and the respective magnetic fluxes are inward in the radial direction. From the mover magnetic flux 124 to the inner space (gap with the armature 110). The magnetic flux radially branches in the circumferential direction and the axial direction, and enters the inside of the iron core 122 from the mover magnetic pole 124 of the N pole of the adjacent magnetic pole block 121. Magnetic fluxes from four magnetic pole blocks 121 adjacent to each other in the circumferential direction and the axial direction enter the iron core 122. Since the north poles of the permanent magnets 123a to 123e face the iron core 122, the magnetic flux further travels inside the iron core 122 and branches into the axial direction, the circumferential direction, and the radial direction outward, respectively, and the permanent magnet. Enter 123a to 123e. The magnetic flux returns from the permanent magnets 123c and 123d to the permanent magnets 123c and 123d adjacent to each other in the circumferential direction. The magnetic flux returns from the permanent magnets 123a and 123b to the permanent magnets 123a and 123b adjacent in the axial direction. Further, the magnetic flux generated from the permanent magnet 123e travels in the back yoke 125 separately in the circumferential direction and the axial direction, and enters the permanent magnet 123e of the magnetic pole block 121 adjacent in the circumferential direction and the axial direction.

The mover magnetic pole 124 has the same polarity as the magnetic poles of the permanent magnets 123a to 123e facing the iron core 122 including the mover magnetic pole 124. That is, when the S poles of the permanent magnets 123a to 123e face the iron core 122, the movable element magnetic pole 124 of the iron core 122 becomes the S pole, and the N poles of the permanent magnets 123a to 123e face the iron core 122. The mover magnetic pole 124 of the iron core 122 has an north pole.

In the linear motor 100 having the above configuration, when a current is passed through the armature coil 111, a magnetic field is generated around the armature coil 111. FIG. 7 is a partially enlarged plan sectional view showing a magnetic path generated from the armature coil 111. An annular magnetic path is formed around the cross section of each armature coil 111. At this time, the surface of the teeth portion 112 facing the magnetic pole element 120 becomes a magnetic pole (armature magnetic pole 114).

The magnetic flux generated by the armature coil 111 enters the iron core 122 from the mover magnetic pole 124 through the gap and passes through the permanent magnets 123a to 123d. The magnetic flux that has passed through the permanent magnets 123c and 123d enters the iron core 122 via the permanent magnets 123c and 123d of the adjacent magnetic pole block 121, exits the gap from the armature magnetic pole 124 of the S pole, and is opposed to the permanent magnets 123c and 123d. Enter the armature magnetic pole 114. Although not shown, the magnetic flux that has passed through the permanent magnets 123a and 123b also enters the iron core 122 via the permanent magnets 123a and 123b of the adjacent magnetic pole block 121 and exits the gap from the armature magnetic pole 124 of the S pole. Enters the N-pole armature magnetic flux 114.

The magnetic flux generated by the armature coil 111 may or may not pass through the permanent magnet 123e. Whether or not the magnetic flux passes through the permanent magnet 123e depends on the configuration of the linear motor 100. For example, if the radial dimension of the iron core 122 is small and the distance between the armature magnetic pole 114 and the permanent magnet 123e is short, the magnetic flux generated from the armature magnetic pole 114 easily passes through the permanent magnet 123e, and the radial dimension of the iron core 122 is large. If the distance between the armature magnetic pole 114 and the permanent magnet 123e is long, it is difficult for the magnetic flux generated from the armature magnetic pole 114 to pass through the permanent magnet 123e. In the linear motor 100 according to the present embodiment, since each iron core 122 is surrounded by permanent magnets 123a to 123e, as compared with a rotor having a structure in which permanent magnets are attached only to two surfaces of the conventional iron core, The magnetic flux generated in the mover magnetic pole 124 is increased. Therefore, the magnetic efficiency of the linear motor 100 is improved.

(Embodiment 2)
In the present embodiment, a linear motor including a columnar armature in which a plurality of coils are arranged side by side in the circumferential direction and an annular magnetic pole element in which a part of the coil is missing will be described.

FIG. 8 is a plan view showing the configuration of the linear motor according to the present embodiment. The linear motor 200 includes a columnar armature 210 and an annular magnetic pole 220 with a part missing. The armature 210 and the magnetic pole 220 are arranged coaxially, and the magnetic pole 220 surrounds the armature 210. When the linear motor 200 is driven, the armature 210 and the magnetic pole 220 move relatively linearly. Here, the magnetic pole 220 may be a mover and the armature 210 may be a stator, or the armature 210 may be a mover and the magnetic pole 220 may be a stator. In the present embodiment, a configuration in which the magnetic pole 220 is a mover and the armature 210 is a stator will be described.

The armature 210 has an armature coil 211, a teeth portion 212, and a yoke portion 213. The yoke portion 213 has a columnar shape. Except for a part of the outer circumference from the arc surface of the yoke portion 213, T-shaped tooth portions 212 project outward in the radial direction so as to be arranged at equal intervals in the circumferential direction in a plan view. The teeth portion 212 is also provided side by side from the yoke portion 213 in the axial direction. That is, the armature member 215 according to the present embodiment has a shape in which a part of the teeth portion 112 is removed from the armature member 115 according to the first embodiment. The armature member 215 is made of a soft magnetic material such as soft iron or soft ferrite.

A conducting wire is wound around each tooth portion 212 to form an armature coil 211. Eight armature coils 211 are provided in the circumferential direction. The portion of the armature member 215 where the tooth portion 212 is not provided is referred to as a non-coil portion 216.

Next, the configuration of the magnetic monopole 220 will be described. As shown in FIG. 8, the magnetic pole element 220 has an annular shape in which a part is missing, that is, a C-shape in a plan view, and is arranged on the outer side in the radial direction of the armature 210. More specifically, the missing portion of the magnetic pole element 220 is arranged so as to align with the non-coil portion 216 of the yoke portion 213 in the circumferential direction. The magnetic pole element 220 has a plurality of magnetic pole blocks 121, and these magnetic pole blocks 121 have a structure in which they are arranged in the circumferential direction. Since the configuration of the magnetic pole block 121 is the same as that in the first embodiment, the description thereof will be omitted.

Each of the magnetic pole blocks 121 touches the side surfaces of the rectangle and is connected to each other in the circumferential direction. The mover magnetic poles 124 of the two magnetic pole blocks 121 adjacent to each other in the circumferential direction are different magnetic poles. That is, the magnetic pole blocks 121 are arranged in the circumferential direction so that the different movable magnetic poles 124 are arranged alternately. Therefore, one of the joint surfaces of the magnetic pole blocks 121 adjacent to each other in the circumferential direction has an S pole and the other has an N pole. Therefore, the two adjacent magnetic pole blocks 121 are attracted to each other by the magnetic force, and the plurality of magnetic pole blocks 121 can be easily arranged side by side in the circumferential direction.

Further, a plurality of annular structures in which a plurality of magnetic pole blocks 121 are arranged in a row and a part of which is missing are laminated in the axial direction (not shown). Each of the magnetic pole blocks 121 adjacent to each other in the axial direction are in contact with each other and are connected to each other. The mover magnetic poles 124 of the two magnetic pole blocks 121 adjacent to each other in the axial direction are different magnetic poles from each other. That is, the magnetic pole blocks 121 are arranged in the axial direction so that the different movable magnetic poles 124 are arranged alternately. Therefore, one of the joint surfaces of the magnetic pole blocks 121 adjacent to each other in the axial direction has an S pole and the other has an N pole. Therefore, the two adjacent magnetic pole blocks 121 are attracted to each other by the magnetic force, and the plurality of magnetic pole blocks 121 can be easily arranged side by side in the axial direction.

Further, a back yoke 225 made of a tubular soft magnetic material having a C-shape in a plan view is arranged outside so as to surround the laminated C-shaped structure in a plan view. Therefore, in each magnetic pole block 121, magnetic poles other than the mover magnetic pole 124 are not exposed to the outside, and a magnetic path is formed in the back yoke 225. Since the magnetic path formed in the magnetic pole block 121 according to the present embodiment is the same as that described in the first embodiment, the description thereof will be omitted. Similarly, the magnetic path formed by the armature coil 211 according to the present embodiment is the same as the magnetic path formed by the armature coil 111 according to the first embodiment, and thus the description thereof will be omitted.

An object for transmitting thrust is attached to the missing portion of the magnetic monopole 220. FIG. 9 is a plan view showing a configuration of a rack and pinion mechanism using a linear motor according to the present embodiment, and FIG. 10 is a side view thereof. As shown in FIGS. 9 and 10, the thrust transmission target can be the rack gear 231 in the rack and pinion mechanism 230. In the linear motor 200 according to the present embodiment, since a part of the magnetic pole element 210 is missing, magnetism is not generated in this missing portion, and magnetic attraction generated between the armature 210 and the magnetic pole element 220 is generated. The force becomes non-uniform in the circumferential direction. Therefore, the magnetic monopole 220 is attracted to the armature 210 on the opposite side of the missing portion, and the rack gear 231 is pressed against the pinion gear 232. As a result, both sides of the teeth of the rack gear 231 are in contact with the two teeth of the pinion gear 232, respectively, and backlash is prevented.

(Embodiment 3)
In the present embodiment, a linear motor having magnetic poles arranged so that the same poles are arranged in the circumferential direction and different poles are arranged alternately in the axial direction will be described.

FIG. 11 is a perspective view showing the configuration of the armature according to the present embodiment, and FIG. 12 is a perspective view showing the configuration of the magnetic pole according to the present embodiment. The linear motor according to the present embodiment includes a columnar armature 310 and an annular magnetic pole 320. The armature 310 and the magnetic pole 320 are arranged concentrically, and the magnetic pole 320 surrounds the armature 310. When the linear motor is driven, the armature 310 and the magnetic pole 320 move linearly in the axial direction. Here, the magnetic pole 320 may be a mover and the armature 310 may be a stator, or the armature 310 may be a mover and the magnetic pole 320 may be a stator. In the present embodiment, a configuration in which the magnetic pole element 320 is a mover and the armature 310 is a stator will be described.

The configuration of the armature 310 will be described with reference to FIGS. 13 and 14. FIG. 13 is a plan view showing the configuration of the armature, and FIG. 14 is a view taken along the line BB of FIG. 13, that is, a view when the cylindrical armature is developed in a plane. The armature 310 has an armature coil 311 and a teeth portion 312 and a yoke portion 313. The yoke portion 313 has a cylindrical shape, and from the outer surface thereof, an annular tooth portion 312, which is partially missing so as to substantially go around in the circumferential direction, protrudes outward in the radial direction. Further, the yoke portion 313 is provided with a plurality of tooth portions 312 arranged side by side in the axial direction.

The yoke portion 313 and the teeth portion 312 are integrally formed as an armature member 315. The armature member 315 is made of a soft magnetic material such as soft iron or soft ferrite. An electric wire is wound around each tooth portion 312 to form an armature coil 311. One armature coil 311 substantially goes around the outer circumference of the yoke portion 313.

Next, the configuration of the magnetic monopole 320 will be described. As shown in FIG. 12, the magnetic pole elements 320 have an annular shape and are arranged on the outer side in the radial direction of the armature 310. The magnetic pole element 320 has a plurality of magnetic pole blocks 321 and has a structure in which these magnetic pole blocks 321 are arranged in the circumferential direction.

FIG. 15 is an exploded perspective view showing the configuration of the magnetic pole block 321. The magnetic pole block 321 has an iron core 322 made of a soft magnetic material and five plate-shaped permanent magnets 323a to 323e. The iron core 322 is a hexahedron having two rhombic faces parallel to each other and four faces perpendicular to the two faces, centering on an axis parallel to one diagonal of the rhombus, and circularly forming another diagonal line. It has a three-dimensional shape that is curved in an arc shape. Hereinafter, the rhombic arc plane on the inner side in the circumferential direction is referred to as the "inner rhombic arc plane", and the rhombic arc plane on the outer side in the circumferential direction is referred to as the "outer rhombic arc plane". Each of the faces is called a "side".

The permanent magnets 323a to 323d have a main surface that is the same as or slightly larger than the side surface of the iron core 322, and are attached to each of the permanent magnets 323a to 323d so as to hide the side surface of the iron core 322. The permanent magnet 323e has an arc plate shape having a main surface equal to or slightly larger than the outer rhombic arc surface of the iron core 322, and is attached so as to hide the outer rhombic arc surface. That is, permanent magnets 323a to 323e are attached to the iron core 322 so as to open and surround the inner rhombic arc surface. Further, the permanent magnets 323a to 323e are arranged so that the same magnetic poles are directed to the iron core 322. The open inner rhombic arc surface of the iron core 322 serves as a mover magnetic pole 324. The mover magnetic pole 324 has the same magnetic pole as the magnetic pole on the surface where the permanent magnets 323a to 323e face the iron core 322. Further, the surface of each of the permanent magnets 323a to 323e facing the outside (the surface opposite to the iron core 322) is the opposite magnetic pole of the mover magnetic pole 324.

See FIG. Each of the magnetic pole blocks 321 is in contact with each other and is connected to each other in an axial direction and an oblique direction with respect to the circumferential direction. The mover magnetic poles 324 of the two adjacent magnetic pole blocks 321 are different magnetic poles from each other. That is, each magnetic pole block 321 is arranged in an oblique direction with respect to the axial direction and the circumferential direction so that different movable magnet magnetic poles 324 are arranged alternately. Therefore, one of the joint surfaces of the adjacent magnetic pole blocks 321 is the S pole and the other is the N pole. Therefore, the two adjacent magnetic pole blocks 321 are attracted to each other by the magnetic force, and the plurality of magnetic pole blocks 321 can be easily arranged side by side.

FIG. 16 is a diagram showing a state in which the inner side surface of the magnetic monopole according to the present embodiment is developed in a plane. The magnetic pole blocks 321 are arranged so that the vertices face each other on both sides in the axial direction and both sides in the circumferential direction of one magnetic pole block 321. The mover magnetic poles 324 of the magnetic pole blocks 321 arranged so that their vertices face each other in this way are the same magnetic poles. That is, the magnetic pole block 321 is arranged so that the same mover magnetic poles 324 are arranged in the circumferential direction, and the same mover magnetic poles 324 are arranged so as to be arranged in the axial direction.

In the following description, a group of magnetic pole blocks 321 in which the movable magnetic poles 324 of the rhombic arc surface are arranged in a row in the circumferential direction so that the vertices abut each other are referred to as "rows" of the magnetic pole blocks 321. All mover magnetic poles 324 included in one row are of the same pole. Also, adjacent rows are opposite to each other. As shown in FIG. 16, the first row (the row on one side in the axial direction) is the south pole, the second row (the second row on the one side in the axial direction) is the north pole, and the third row is the north pole. The south pole is used, the fourth row is the north pole, the fifth row is the south pole, and the sixth row is the north pole. In other words, in the magnetic poles 320, the mover magnetic poles 324 are inverted one by one in the front-rear direction, and the same mover magnetic poles 324 are lined up in the circumferential direction of one row.

A back yoke 325 made of a cylindrical soft magnetic material is arranged on the outside so as to surround an annular structure formed by connecting a plurality of magnetic pole blocks 321 to each other as described above. Therefore, in each magnetic pole block 321, magnetic poles other than the mover magnetic pole 324 are not exposed to the outside, and a magnetic path is formed in the back yoke 325.

When a current is passed through the armature coil 311 in a linear motor having the above configuration, a magnetic field is generated around the armature coil 311. An annular magnetic path is formed around the cross section of each armature coil 311. At this time, the surface of the teeth portion 312 facing the magnetic pole element 320 becomes the armature magnetic pole 314 (see FIG. 11).

When a current flows through the armature coil 311, the armature magnetic pole 314 and the mover magnetic pole 324 are attracted or repelled by the magnetic force. By controlling the current flowing through the armature coil 311 the magnetic field generated by the armature coil 311 changes, which causes the monopole 320 to move in the axial direction. Magnetic flux is emitted radially from the armature magnetic pole 314 of the annular S pole. The magnetic flux enters each mover pole 324 in a row of N poles arranged in an annular shape and passes through all the permanent magnets 323 in contact with the iron core 322 having the mover pole 324. The magnetic flux emitted from the permanent magnet 323 enters the permanent magnet 323 of each magnetic pole block 321 in the adjacent row of S poles, exits from each movable armature magnetic pole 324 of the S poles arranged in an annular shape, and has an annular north pole. Enter the armature magnetic pole 314. That is, in the linear motor according to the present embodiment, the magnetic flux generated by the armature 310 passes through all the permanent magnets 323 of the magnetic pole block 321. In the monopole 320, since each iron core 322 is surrounded by a permanent magnet 323, the magnetic flux generated in the mover magnetic pole 324 is increased as compared with a magnetic pole having a structure in which permanent magnets are attached only to two surfaces of the conventional iron core. Will be done. Therefore, the magnetic efficiency of the linear motor is improved.

(Embodiment 4)
In the present embodiment, permanent magnets are attached to five surfaces of a polyhedron-shaped iron core having two trapezoidal trapezoidal surfaces parallel to each other and four side surfaces perpendicular to the two trapezoidal surfaces in the axial direction. A linear motor having a magnetic pole element composed of the magnetic pole blocks provided will be described.

Since the configuration of the armature according to the present embodiment is the same as the configuration of the armature according to the first embodiment, the same components are designated by the same reference numerals and the description thereof will be omitted.

The configuration of the magnetic pole element according to the present embodiment will be described. FIG. 17 is a plan sectional view showing the configuration of the magnetic pole element according to the present embodiment. The magnetic monopole 420 has a polygonal annular shape and is arranged on the outer side in the radial direction of the armature 110. The magnetic pole element 420 has a plurality of magnetic pole blocks 421, and has a structure in which these magnetic pole blocks 421 are arranged in the circumferential direction.

FIG. 18 is an exploded perspective view showing the configuration of the magnetic pole block 421. The magnetic pole block 421 has an iron core 422 made of a soft magnetic material and five plate-shaped permanent magnets 423a to 423e. The iron core 422 has a polyhedral shape having two trapezoidal surfaces parallel to each other in the axial direction (hereinafter referred to as "trapezoidal surfaces") and four side surfaces perpendicular to these trapezoidal surfaces. The permanent magnets 423a and 423b have a trapezoidal main surface that is the same as or slightly larger than the trapezoidal surface of the iron core 422, and are attached to each of them so as to hide the trapezoidal surface of the iron core 422. The permanent magnets 423c and 423d have a width equal to or slightly larger than the axial length of the iron core 422, respectively, so as to hide the trapezoidal leg-side side surface (that is, the side surface parallel to the radial direction) of the iron core 422. It is attached. Further, the permanent magnet 423e has a width equal to or slightly larger than the axial length of the iron core 422, so as to hide the side surface of the iron core 422 on the lower bottom side (that is, the side surface facing outward in the radial direction). Attached to. That is, the permanent magnets 423a to 423e are attached to the iron core 422 so as to open and surround the side surface on the upper bottom side of the trapezoid (that is, the side surface facing inward in the radial direction). Further, the permanent magnets 423a to 423e are arranged with the same magnetic poles facing the iron core 422. The open side surface of the iron core 422 becomes the mover magnetic pole 424. The mover magnetic pole 424 has the same magnetic pole as the magnetic pole on the surface where the permanent magnets 423a to 423e face the iron core 422. Further, the surface of each of the permanent magnets 423a to 423e facing the outside (the surface opposite to the iron core 422) is the opposite magnetic pole of the mover magnetic pole 424.

See FIG. Each of the magnetic pole blocks 421 touches the side surfaces of the trapezoid on the leg side and is connected to each other in the circumferential direction. The mover magnetic poles 424 of the two magnetic pole blocks 421 adjacent to each other in the circumferential direction are different magnetic poles. That is, each magnetic pole block 421 is arranged in the circumferential direction so that different movable magnet magnetic poles 424 are arranged alternately. Therefore, one of the joint surfaces of the magnetic pole blocks 421 adjacent to each other in the circumferential direction has an S pole and the other has an N pole. Therefore, the two adjacent magnetic pole blocks 421 are attracted to each other by the magnetic force, and the plurality of magnetic pole blocks 421 can be easily arranged side by side in the circumferential direction.

Further, a plurality of annular structures in which a plurality of magnetic pole blocks 421 are arranged in a row are laminated in the axial direction. Each of the magnetic pole blocks 421 adjacent to each other in the axial direction are connected to each other with the trapezoidal surfaces in contact with each other. The mover magnetic poles 424 of the two magnetic pole blocks 421 adjacent to each other in the axial direction are different magnetic poles from each other. That is, each magnetic pole block 421 is arranged in the axial direction so that different movable magnet magnetic poles 424 are arranged alternately. Therefore, one of the joint surfaces of the magnetic pole blocks 421 adjacent to each other in the axial direction has an S pole and the other has an N pole. Therefore, the two adjacent magnetic pole blocks 421 are attracted to each other by the magnetic force, and the plurality of magnetic pole blocks 421 can be easily arranged side by side in the axial direction.

Further, a back yoke 425 made of a polygonal tubular soft magnetic material is arranged on the outside so as to surround the laminated annular structure. Therefore, in each magnetic pole block 421, magnetic poles other than the mover magnetic pole 424 are not exposed to the outside, and a magnetic path is formed in the back yoke 425. The apex of the outer peripheral surface of the back yoke 425 is provided on the outer side in the radial direction of the joining position of the two adjacent magnetic pole blocks 421. The radial outer portion of the joint position of the two adjacent magnetic pole blocks 421 is a portion through which the magnetic flux that exits from the permanent magnet 423e of one magnetic pole block 421 and enters the permanent magnet 423e of the other magnetic pole block 421 passes through. concentrate. Therefore, by providing the apex in this portion, the cross-sectional area of the portion when cut in the radial direction becomes large, and magnetic saturation can be suppressed.

(Embodiment 5)
In the present embodiment, six surfaces of a three-dimensional iron core having two parallel main surfaces having a pentagonal arcuate side in the axial direction and five sides perpendicular to the two main surfaces. A linear motor having a magnetic pole element composed of a magnetic pole block to which a permanent magnet is attached will be described.

Since the configuration of the armature according to the present embodiment is the same as the configuration of the armature according to the first embodiment, the same components are designated by the same reference numerals and the description thereof will be omitted.

The configuration of the magnetic pole element according to the present embodiment will be described. FIG. 19 is a plan sectional view showing the configuration of the magnetic pole element according to the present embodiment. The magnetic monopole 520 has an annular shape and is arranged on the outer side in the radial direction of the armature 110. The magnetic pole element 520 has a plurality of magnetic pole blocks 521, and has a structure in which these magnetic pole blocks 521 are arranged in the circumferential direction.

FIG. 20 is an exploded perspective view showing the configuration of the magnetic pole block 521. The magnetic pole block 521 has an iron core 522 made of a soft magnetic material and six plate-shaped permanent magnets 523a to 523f. The iron core 522 has a three-dimensional shape having two main surfaces parallel to each other in a planar shape in which one side of the pentagon is an arc in the axial direction, and five side surfaces perpendicular to these main surfaces. .. The permanent magnets 523a and 523b have a main surface having the same or slightly larger shape as the substantially pentagonal main surface of the iron core 522, and are attached to each of them so as to hide the main surface of the iron core 522. The permanent magnets 523c to 523f have a width equal to or slightly larger than the axial length of the iron core 522, and are attached to each of the permanent magnets 522 so as to hide the side surfaces of the iron core 522 other than the arc surface. That is, the permanent magnets 523a to 523f are attached to the iron core 522 so as to open and surround the arc surface (that is, the side surface facing inward in the radial direction). Further, the permanent magnets 523a to 523f are arranged so that the same magnetic poles are directed to the iron core 522. The open arc surface of the iron core 522 becomes the mover magnetic pole 524. The mover magnetic pole 524 has the same magnetic pole as the magnetic pole on the surface where the permanent magnets 523a to 523f face the iron core 522. Further, the surface of each permanent magnet 523a to 523f facing outward (the surface opposite to the iron core 522) is the opposite magnetic pole of the mover magnetic pole 524.

See FIG. Each of the magnetic pole blocks 521 is in contact with the side surfaces connected to the arc surface (that is, the side surfaces parallel to the radial direction) and are connected to each other in the circumferential direction. The mover magnetic poles 524 of the two magnetic pole blocks 521 adjacent to each other in the circumferential direction are different magnetic poles. That is, each magnetic pole block 521 is arranged in the circumferential direction so that different movable magnet magnetic poles 524 are arranged alternately. Therefore, one of the joint surfaces of the magnetic pole blocks 521 adjacent to each other in the circumferential direction has an S pole and the other has an N pole. Therefore, the two adjacent magnetic pole blocks 521 are attracted to each other by the magnetic force, and the plurality of magnetic pole blocks 521 can be easily arranged side by side in the circumferential direction.

Further, a plurality of annular structures in which a plurality of magnetic pole blocks 521 are arranged in a row are laminated in the axial direction. Each of the magnetic pole blocks 521 adjacent in the axial direction are connected to each other with the main surfaces of the substantially pentagons in contact with each other. The mover magnetic poles 524 of the two magnetic pole blocks 521 adjacent in the axial direction are different magnetic poles from each other. That is, each magnetic pole block 521 is arranged in the axial direction so that different movable magnet magnetic poles 524 are arranged alternately. Therefore, one of the joint surfaces of the magnetic pole blocks 521 adjacent to each other in the axial direction has an S pole and the other has an N pole. Therefore, the two adjacent magnetic pole blocks 521 are attracted to each other by the magnetic force, and the plurality of magnetic pole blocks 521 can be easily arranged side by side in the axial direction.

Further, a back yoke 525 made of a cylindrical soft magnetic material is arranged on the outside so as to surround the laminated annular structure. Therefore, in each magnetic pole block 521, magnetic poles other than the mover magnetic pole 524 are not exposed to the outside, and a magnetic path is formed in the back yoke 525.

As described above, in the magnetic pole block 521 according to the present embodiment, since the two permanent magnets 523e and 523f are provided so as to incline with each other at a predetermined angle on the outer side in the radial direction, as in the fourth embodiment. The surface area of the permanent magnet can be increased as compared with the configuration in which one permanent magnet 423e is provided on the outer side in the radial direction. Therefore, the amount of magnetic flux generated by the magnetic pole block 521 can be increased, and the magnetic characteristics can be improved.

(Other embodiments)
In the above-described first to fifth embodiments, the configuration in which each of the magnetic pole blocks has a unique permanent magnet has been described, but the present invention is not limited thereto. Adjacent magnetic pole blocks may be configured to share one permanent magnet. FIG. 21 is a plan sectional view showing a modified example of the configuration of the magnetic pole. As shown in FIG. 21, in the magnetic pole element 620 shown in this example, a plate-shaped permanent magnet 623 extending in the radial direction is shared by magnetic pole blocks 621 adjacent to each other in the circumferential direction. That is, one permanent magnet 623 is arranged between two iron cores 622 adjacent to each other in the circumferential direction. The surface of the south pole of the permanent magnet 623 is joined to one iron core 622, and the mover magnetic pole 624 of the iron core 622 is the south pole. On the other hand, the surface of the north pole of the permanent magnet 623 is joined to another iron core 622, and the mover magnetic pole 624 of this iron core 622 is the north pole.

Further, in the above-described third to fifth embodiments, the configuration in which the magnetic monopole is annular has been described, but the present invention is not limited to this. Similar to the second embodiment, the magnetic pole element may be an annular shape in which a part in the circumferential direction is missing, and a thrust transmission target such as a rack and pinion mechanism may be attached to the missing portion.

The linear motor of the present invention is useful as a linear motor including a magnetic pole having a permanent magnet and an iron core.

100,200, Linear motor 101 Central axis 110,210,310 Armature 111,211,311 Armature coil 112,212,312 Teeth part 113,213,313 York part 114 Armature magnetic pole 115,215,315 Armature Members 120, 220, 320, 420, 520, 620 Armatures 121, 321, 421, 521, 621 Magnetic pole blocks 122, 322, 422, 522,622 Iron cores 123a to 123e, 323a to 323e, 423a to 423e, 523a to 523f , 623 Permanent magnet 124,324,424,524,624 Movable armature poles 125,225,325,425,525 Back yoke 216 Non-coil part 230 Rack and pinion mechanism 231 Rack gear 232 Pinion gear

Claims (7)

A columnar armature in which multiple coils are arranged side by side in the circumferential direction,
A magnetic monopole that surrounds the armature is provided.
The magnetic pole has a plurality of magnetic pole blocks including an iron core arranged so as to face the coil and a plurality of permanent magnets that open the surface facing the coil and surround the iron core.
In the magnetic pole block, the plurality of permanent magnets are arranged with the same magnetic pole facing the iron core .
Each of the plurality of magnetic pole blocks is arranged so that different magnetic poles are arranged alternately in the circumferential direction, and different magnetic poles are arranged so as to be arranged alternately in the longitudinal direction of the armature.
The magnetic flux emitted from the open side surface of the one magnetic pole block branches in the circumferential direction and the longitudinal direction, and the other magnetic pole adjacent to the one magnetic pole block in the circumferential direction and the longitudinal direction. Enter the block,
Linear motor. Adjacent magnetic pole blocks have one side of a permanent magnet in close contact with each other.
The linear motor according to claim 1. The iron core has a three-dimensional shape having two fan-shaped circular fan-shaped surfaces having a missing tip in the longitudinal direction of the armature and four side surfaces perpendicular to the two annular fan-shaped surfaces. None,
The magnetic pole block is configured by attaching the permanent magnet to each of five surfaces of the iron core other than the radial inner side surface of the fan shape.
The linear motor according to claim 2. The iron core has a polyhedral shape having two trapezoidal surfaces parallel to each other in the longitudinal direction of the armature and four side surfaces perpendicular to the two trapezoidal surfaces.
The magnetic pole block is configured by attaching the permanent magnet to each of five surfaces of the iron core other than the side surface on the upper bottom side of the trapezoid.
The linear motor according to claim 2. The iron core has a three-dimensional shape having two main surfaces parallel to each other in a shape in which one side of a pentagon is arcuate in the longitudinal direction of the armature, and five side surfaces perpendicular to the two main surfaces. ,
The magnetic pole block is configured by attaching the permanent magnet to each of six surfaces of the iron core other than the arcuate side surface.
The linear motor according to claim 2. The iron core is a hexahedron having two faces of a rhombus parallel to each other and four faces perpendicular to the two faces, and the other diagonal lines are centered on an axis parallel to one diagonal line of the rhombus. It has a three-dimensional shape curved in an arc shape,
The magnetic pole block is configured by attaching the permanent magnet to each of five surfaces other than the arc surface on the inner side in the radial direction of the iron core.
The linear motor according to claim 2. The monopole is configured in an annular shape with a part missing to attach an object that transmits thrust.
The linear motor according to any one of claims 1 to 6.

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