JP7179284B2 - stator core structure - Google Patents

Description

The present invention relates to stator core structures.

As a conventional stator core structure used for strain sensors, for example, a stator core structure described in Patent Document 1 below is known. That is, FIG. 5 is a developed plan view of a conventional stator core structure 1, and a plurality of detection coils 3a, 3b each having a detection winding wound around a plurality of cores 2a, 2b are arranged in the circumferential direction B of the annular stator core structure 1. is doing. In order to impart anisotropy to the rotating shaft (not shown), the detection coils 3a and 3b are arranged in two rows in the axial direction A, so that the stator core structure 1 as a whole has multiple detection coils.

Further, as another example of conventional stator core structures used in strain sensors, for example, a stator core structure described in Japanese Patent Application No. 2018-107624, which is an unpublished patent application, is known. That is, FIG. 6 is a developed plan view of the annular stator core 2 of the conventional stator core structure 1a, in which a plurality of protruding magnetic poles 4 protruding inward at predetermined angular intervals are formed in two rows in the axial direction A. It is A winding (not shown) is wound around each protruding magnetic pole 4, and by detecting a change in magnetic flux M in an oblique direction, distortion of a rotating shaft (not shown) is detected.

JP 2010-145099 A

In the conventional stator core structure 1 described in Patent Document 1 as described above, since the detection coils 3a and 3b are arranged in two rows in the axial direction A, the thickness of the stator core structure 1 in the axial direction A is increased. There was a problem. Further, in the stator core structure 1a described in Japanese Patent Application No. 2018-107624 as described above, since the protruding magnetic poles 4 are formed in two rows in the axial direction, the thickness of the annular stator core 2 in the axial direction A is increased, There is a problem that the overall thickness of the stator core structure 1a is increased.

SUMMARY OF THE INVENTION An object of the present invention is to provide a stator core structure with a reduced thickness in the axial direction.

In order to solve the above problems, a stator core structure according to the present invention includes a ring-shaped stator core, and projecting magnetic poles protruding inwardly at predetermined angular intervals on the inner surface of the ring-shaped stator core and having windings wound thereon. , and a flange formed at the tip of the projecting magnetic pole, the flange has a pair of first and second slanted portions formed on both sides of the flange; The first slanted portions of the adjacent flange portions face each other along the circumferential direction of the annular stator core, and the second slanted portions of the adjacent flange portions face each other. A first magnetic path is formed between the protruding magnetic pole and the protruding magnetic pole adjacent in one of the circumferential directions, and between the protruding magnetic pole and the protruding magnetic pole adjacent in the other circumferential direction of the protruding magnetic pole. A second magnetic path is formed.

The collar may be trapezoidal when viewed from the inside.
The collar may be triangular when viewed from the inside.
The protruding magnetic poles may be formed in a plurality of rows along the axial direction of the annular stator core, and the flange portions of the protruding magnetic poles of other rows adjacent in the axial direction may be formed upside down. .

The stator core structure according to the present invention has a pair of first slanted portions and second slanted portions formed on both sides of the brim portion, and each of the brim portions has a shape that is different from each other along the circumferential direction of the annular stator core. A first magnetic path is formed between the protruding magnetic pole and the protruding magnetic pole adjacent to the protruding magnetic pole in one of the circumferential directions, and the protruding magnetic pole and the protruding magnetic pole in the circumferential direction are formed differently. Since the second magnetic path is formed between the protruding magnetic poles adjacent to the other, it is possible to provide a stator core structure with a reduced thickness in the axial direction.

1 is a schematic diagram of a stator core structure according to Embodiment 1 of the present invention; FIG. FIG. 2 is a developed view of the projecting magnetic pole shown in FIG. 1 as seen from the inside; FIG. 10 is a developed view of the projecting magnetic pole according to the second embodiment of the present invention, viewed from the inside; FIG. 10 is a developed view of a protruding magnetic pole according to Embodiment 3 of the present invention, viewed from the inside; 1 is a schematic diagram of a conventional stator core structure; FIG. 1 is a schematic diagram of another conventional stator core structure; FIG.

Embodiment 1.
Embodiment 1 of the present invention will be described below with reference to FIGS. 1 and 2 of the accompanying drawings. Identical or equivalent portions to those of the conventional example are denoted by the same reference numerals.
FIG. 1 is a schematic plan view of a stator core structure 10 according to Embodiment 1 of the present invention, viewed from above. The stator core structure 10 is a stator core structure used for a strain sensor and has an annular stator core 20 . The annular stator core 20 is formed by laminating a plurality of electromagnetic steel sheets. A plurality of inwardly projecting magnetic poles 40 are formed on the inner surface of the annular stator core 20 at predetermined angular intervals, and slots 50 are respectively formed between the projecting magnetic poles 40 . In the first embodiment, a total of eight protruding magnetic poles 40 are formed. A flange portion 45 is formed at the tip of each protruding magnetic pole 40 . An excitation winding and a detection winding (not shown) are wound around each protruding magnetic pole 40 . The connection wires between the excitation windings, the connection wires between the detection windings, the terminals connected to the excitation windings and the detection windings, and the like are known structures, and therefore the description thereof is omitted.

A rotating shaft 60 extending in the axial direction A, which is the vertical direction of the ring-shaped stator core 20 of the stator core structure 10 , is provided inside the protruding magnetic poles 40 of the stator core structure 10 in the radial direction. The rotating shaft 60 may have a magnetostrictive material portion on its surface, or may be entirely formed of a magnetostrictive material portion.

FIG. 2 is a schematic development of four protruding magnetic poles 40 out of the protruding magnetic poles 40 shown in FIG. 1 when viewed from the inside of the ring-shaped stator core 20, that is, along the radial direction C (see FIG. 1). It is a diagram. The flange portion 45 of the protruding magnetic pole 40 has a trapezoidal shape when viewed from the inside of the ring-shaped stator core 20 , and has a narrow portion 41 extending along the circumferential direction B of the ring-shaped stator core 20 and a wider width than the narrow portion 41 . a wide portion 42 extending along the circumferential direction B; and a pair of first slanted portion 43 and second slanted portion 44 formed on both sides of the flange portion 45 and connecting the narrow portion 41 and the wide portion 42. have The flange portion 45 is formed so that the first slanted portion 43 is positioned on the right side and the second slanted portion 44 is positioned on the left side when the wide portion 42 is positioned downward. The narrow portion 41 and the wide portion 42 are parallel, and the first slanted portion 43 and the second slanted portion 44 are not parallel. That is, the first slanted portion 43 and the second slanted portion 44 are formed not parallel to the axial direction A but obliquely. Also, the first slanted portion 43 and the second slanted portion 44 are formed to have approximately the same dimensions.

The collar portions 45 are provided so as to be upside down with respect to the adjacent collar portions 45 . For example, in FIG. 2, the leftmost collar portion 45 has the narrow portion 41 on the upper side and the wide portion 42 on the lower side, while the adjacent collar portion 45 on the right side has the narrow portion 41 on the upper side and the wide portion 42 on the lower side. It has a wide portion 42 and the narrow portion 41 on the lower side. The first slanted portion 43 of the flange portion 45 is opposed to the first slanted portion 43 of the brim portion 45 adjacent to the right side, and the second slanted portion 44 of the brim portion 45 has a left The second slanted portions 44 of the collar portions 45 adjacent to each other in the direction face each other. That is, each of the flanges 45 having a trapezoidal shape when viewed in the radial direction C is arranged with respect to the adjacent flanges 45 such that the shapes thereof are different from each other along the circumferential direction B of the annular stator core 20 . The top and bottom are arranged alternately.

Two different first magnetic paths a and second magnetic paths b are alternately formed between the adjacent protruding magnetic poles 40 by the excitation windings and the detection windings wound around the protruding magnetic poles 40 . The first magnetic path a is formed so as to pass through the first slanted portions 43 of the adjacent flange portions 45 . The second magnetic path b is formed so as to pass through the second inclined portions 44 of the adjacent flange portions 45 . Since the first slanted portion 43 and the second slanted portion 44 are not parallel, the first magnetic path a and the second magnetic path b are formed in different directions. Therefore, the first magnetic path a and the second magnetic path b impart two types of anisotropy to the magnetostrictive material portion of the rotating shaft 60 (see FIG. 1).

As shown in FIG. 1 , when a force is applied to the rotating shaft 60 , the magnetic permeability of the magnetostrictive material portion of the rotating shaft 60 changes due to the strain generated in the rotating shaft 60 . Next, the magnetic fluxes of the first magnetic path a and the second magnetic path b (see FIG. 2) change due to changes in the magnetic permeability of the magnetostrictive material portion, and the impedance of the detection winding changes due to the magnetic flux changes. This change in impedance changes the output signal voltage of the sensing winding. By comparing the change in the output signal voltage of the detection winding before and after the force is applied to the rotating shaft 60, the direction and magnitude of the strain generated in the rotating shaft 60 can be detected.

In this way, the ring-shaped stator core 20, the protruding magnetic poles 40 protruding inwardly at predetermined angular intervals on the inner surface of the ring-shaped stator core 20 and having windings wound thereon, and the tips of the protruding magnetic poles 40 A stator core structure comprising a flange portion 45 having a pair of the first slanted portion 43 and the second slanted portion 44 formed on both sides of the flange portion 45, each of the flange portions 45 having the The protruding magnetic poles 40 are formed to have different shapes along the circumferential direction B of the ring-shaped stator core 20, and the protruding magnetic poles 40 adjacent to each other in the circumferential direction B of the protruding magnetic poles 40 have the first magnetic poles 40 therebetween. One magnetic path a is formed, and the second magnetic path b is formed between the protruding magnetic pole 40 and the protruding magnetic pole 40 adjacent to the protruding magnetic pole 40 on the other side in the circumferential direction B. Therefore, the stator core Only one row of the protruding magnetic poles 40 provided in the structure 10 is sufficient, and the thickness of the stator core structure 10 in the axial direction A can be reduced.

Further, since the flange portion 45 has a trapezoidal shape when viewed from the inside of the ring-shaped stator core 20, the protruding magnetic poles 40 can be arranged by efficiently utilizing the space along the circumferential direction B of the ring-shaped stator core 20. and the stator core structure 10 can be made more compact.

Further, in the conventional stator core structure 1 described in Patent Document 1 shown in FIG. 5, strain cannot be detected in the entire circumferential direction B because magnetic paths do not pass between the cores 2a and 2b. On the other hand, in the stator core structure 10 shown in FIG. The strain can be detected as a whole, and the sensitivity of the strain sensor is improved.

In the first embodiment, the first slanted portion 43 and the second slanted portion 44 of the flange portion 45 are formed to have approximately the same dimensions, but they are formed to have different dimensions. may be Further, although the narrow portion 41 and the wide portion 42 of the flange portion 45 are formed in parallel, the narrow portion 41 and the wide portion 42 may not be parallel.

Further, although eight protruding magnetic poles 40 are formed in the first embodiment, the number is not limited to this, and a plurality of protruding magnetic poles may be formed.

Embodiment 2.
Next, a stator core structure according to Embodiment 2 of the present invention will be described. In the following embodiments, the same reference numerals as those in FIGS. 1 and 2 denote the same or similar components, so detailed description thereof will be omitted.
The stator core structure according to the second embodiment differs from the first embodiment in that the flanges of the projecting magnetic poles are triangular in shape when viewed from the radial direction.

FIG. 3 is a schematic development of four protruding magnetic poles 40a out of the protruding magnetic poles 40a according to the second embodiment of the present invention, viewed from the inside of the ring-shaped stator core 20, that is, from the radial direction C (see FIG. 1). It is a diagram. The flange portion 45a of the protruding magnetic pole 40a has an equilateral triangle shape when viewed from the inside of the annular stator core 20, and is adjacent to the bottom portion 42a extending along the circumferential direction B of the annular stator core 20 and the bottom portion 42a. It has a first slanted portion 43a and a second slanted portion 44a. The flange portion 45a is formed so that the first slanted portion 43a is positioned on the right side and the second slanted portion 44a is positioned on the left side when the bottom portion 42a faces downward. Further, the flange portion 45a is provided so as to be upside down with respect to the adjacent flange portion 45a. That is, the first slanted portion 43a of the protruding magnetic pole 40a faces the first slanted portion 43a of the flange portion 45a adjacent to the right, and the second slanted portion 44a of the flange portion 45a faces the left side. The second slanted portions 44a of the collar portions 45a adjacent to each other in the direction face each other. That is, each of the flanges 45a having an equilateral triangular shape when viewed from the radial direction C is arranged with respect to the adjacent flanges 45a such that the shapes thereof are different from each other along the circumferential direction B of the annular stator core. The top and bottom are alternately formed.

Two different first magnetic paths a and second magnetic paths b are alternately formed between the adjacent protruding magnetic poles 40a by the excitation windings and the detection windings wound around the protruding magnetic poles 40a. be. The first magnetic path a is formed so as to pass through the first slanted portions 43a of the adjacent flange portions 45a. The second magnetic path b is formed so as to pass through the second inclined portions 44a of the adjacent flange portions 45a. The first magnetic path a and the second magnetic path b are formed in different directions. to give Other configurations are the same as those of the first embodiment.

Thus, since the projecting magnetic pole 40a is triangular when viewed from the radial direction C, the wide portion 42 of the flange portion 45 of the first embodiment and the bottom portion 42a of the flange portion 45a of the second embodiment have the same width in the circumferential direction B, the first slanted portion 43 and the second slanted portion 44 of the brim portion 45 of the first embodiment are less likely to be slanted than the first slanted portion 43 and the second slanted portion 44 of the brim portion 45 of the first embodiment. The first slanted portion 43a and the second slanted portion 44a of 45a can be formed wide. As a result, the widths of the first slanted portion 43a and the second slanted portion 44a through which the first magnetic path a and the second magnetic path b pass are widened, thereby improving the sensitivity of the strain sensor.

In the second embodiment, the flange portion 45a has the shape of an equilateral triangle when viewed from the inside of the annular stator core 20, but may have another shape such as an isosceles triangle.

Embodiment 3.
Next, a stator core structure according to Embodiment 3 of the present invention will be described with reference to FIG. The stator core structure according to the third embodiment is different from the first embodiment in that protruding magnetic poles are formed in two rows in the axial direction.

FIG. 4 is a schematic view of eight protruding magnetic poles 40 out of the protruding magnetic poles 40 according to Embodiment 3 of the present invention, viewed from the inside of the ring-shaped stator core 20, that is, from the radial direction C (see FIG. 1). It is a development view.
The annular stator core 20 is formed with the protruding magnetic poles 40 in the first row and the protruding magnetic poles 40 in the second row. the narrow portion 41 of the flange portion 45 of the protruding magnetic pole 40 in the first row and the narrow portion 41 of the flange portion 45 of the protruding magnetic pole 40 in the second row face each other along the axial direction A; The wide portions 42 of the flange portions 45 of the protruding magnetic poles 40 in the first row and the wide portions 42 of the protruding magnetic poles 40 in the second row face each other along the axial direction A. The protruding magnetic poles 40 in each row are arranged so that the shapes of the flange portions 45 are different. That is, the protruding magnetic poles 40 are formed in two rows along the axial direction A so that the flange portions 45 of the protruding magnetic poles 40 of the first row and the second row are upside down. Other forms are the same as those of the first embodiment.

In this manner, the protruding magnetic poles 40 are formed in two rows along the axial direction A of the annular stator core 20, and the protruding magnetic poles 40 of another row adjacent to the axial direction A and the flange portion 45 have a shape of Since the first magnetic path a and the second magnetic path b are formed without interruption in the circumferential direction B, the influence of the eccentricity of the rotating shaft 60 (see FIG. 1) and the above The influence of winding variations in the circumferential direction B is reduced, and the accuracy of the strain sensor can be improved.

Further, in the conventional stator core structure 1a described in Japanese Patent Application No. 2018-107624 shown in FIG. Since the leakage magnetic flux N in the lateral direction where the distance between the magnetic poles 4 is the shortest, that is, the circumferential direction B, is stronger than the magnetic flux M, it is difficult to sufficiently detect the change in the magnetic flux M. On the other hand, in the stator core structure 10 according to the third embodiment, it is possible to reduce the leakage magnetic flux in the circumferential direction B and increase the magnetic flux in the directions of the first magnetic path a and the second magnetic path b. Therefore, the sensitivity and accuracy of the strain sensor can be improved.

In the third embodiment, the protruding magnetic poles 40 are formed in two rows along the axial direction A. However, if the directions of the flange portions 45 in rows adjacent to each other along the axial direction A are upside down. The protruding magnetic poles 40 may be formed in three or more rows in the axial direction A, as long as they are formed in such a manner as to be. Further, although the flange portion 45 has a trapezoidal shape when viewed from the inside of the annular stator core 20, it may have a triangular shape (see FIG. 3) as in the second embodiment.

Further, the stator core structures according to Embodiments 1 to 3 are used for strain sensors, but may be used for other types of sensors using magnetic flux, such as angle sensors.

Further, the flange portion 45 according to Embodiments 1 and 3 has a trapezoidal shape when viewed from the inside of the annular stator core 20, and the flange portion 45a according to Embodiment 2 has a shape similar to that of the annular stator core 20. When viewed from the inside, the shape of the ring-shaped stator core was triangular. , a polygon with rounded corners, or any other shape.

The stator core structure according to the present invention is as follows. That is, the ring-shaped stator core 20, the protruding magnetic poles 40 protruding inwardly at predetermined angular intervals on the inner surface of the ring-shaped stator core 20 and wound with windings, and the protruding magnetic poles 40 formed at the tips of the protruding magnetic poles 40. and a pair of the first slanted portion 43 and the second slanted portion 44 formed on both sides of the brim portion 45, and each of the brim portions 45 has the annular shape. The first magnetic poles 40 are formed to have different shapes along the circumferential direction B of the stator core 20 , and the first magnetic poles 40 are formed between the magnetic poles 40 adjacent to each other in the circumferential direction B of the magnetic poles 40 . A magnetic path a is formed, and the second magnetic path b is formed between the protruding magnetic pole 40 and the protruding magnetic pole 40 adjacent to the protruding magnetic pole 40 on the other side in the circumferential direction B, and The flange portion 45 has a trapezoidal configuration when viewed from the inside of the annular stator core 20, and the flange portion 45a has a triangular configuration when viewed from the inside of the annular stator core 20. The protruding magnetic poles 40 are formed in two rows along the axial direction A of the annular stator core 20, and are formed so as to have a shape different from that of the flange portions 45 of other adjacent rows along the axial direction A. is.

The stator core structure according to the present invention includes a ring-shaped stator core, protruding magnetic poles protruding inwardly at predetermined angular intervals on the inner surface of the ring-shaped stator core and having windings wound thereon, and flanges formed at the tips of the protruding magnetic poles. and a pair of first slanted portions and second slanted portions formed on both sides of the flange portion, and each flange portion is formed to have a different shape from each other along the circumferential direction of the ring-shaped stator core. A first magnetic path is formed between the protruding magnetic pole and the protruding magnetic pole adjacent in one circumferential direction of the protruding magnetic pole, and the protruding magnetic pole and the protruding magnetic pole adjacent in the other circumferential direction of the protruding magnetic pole Since the second magnetic path is formed between , the thickness in the axial direction can be reduced.

20 Annular stator core 40, 40a Protruding magnetic pole 43 First slanted portion 44 Second slanted portion 45, 45a Flange A Axial direction B Circumferential direction a First magnetic path b Second magnetic path

Claims (4)

an annular stator core (20);
protruding magnetic poles (40) protruding inwardly at predetermined angular intervals from the inner surface of the annular stator core (20) and wound with windings;
In a stator core structure comprising a flange (45) formed at the tip of the protruding magnetic pole (40),
A pair of first slanted portion (43) and second slanted portion (44) formed on both sides of the collar (45),
In each of the flange portions (45), the first inclined portions (43) of the flange portions (45) adjacent to each other along the circumferential direction (B) of the annular stator core (20) face each other and are adjacent to each other. The second inclined portions (44) of the portion (45) are formed so as to face each other ,
A first magnetic path (a) is formed between the protruding magnetic pole (40) and the protruding magnetic pole (40) adjacent to the protruding magnetic pole (40) in one of the circumferential directions (B), and the protruding magnetic pole A stator core characterized in that a second magnetic path (b) is formed between (40) and the protruding magnetic pole (40) adjacent to the other protruding magnetic pole (40) in the circumferential direction (B). structure. The stator core structure according to claim 1, wherein said flange (45) has a trapezoidal shape when viewed from the inside. The stator core structure according to claim 1, wherein said flange (45) is triangular when viewed from said inside. The protruding magnetic poles (40) are formed in a plurality of rows along the axial direction (A) of the annular stator core (20). The stator core structure according to any one of claims 1 to 3, wherein the flange (45) is formed upside down .

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