JP7351471B2 - stator core structure - Google Patents

Description

The present invention relates to a stator core structure, and particularly to a stator core structure having oblique grooves.

As a stator core structure used in a strain sensor or a rotation sensor, for example, the stator core structure described in Patent Document 1 below is known. In the conventional stator core structure 10A shown in FIG. 4, protruding magnetic poles 30A are formed inward from the annular stator core 20A. When the configuration of FIG. 4 is used as a strain sensor, in order to improve the characteristics as a strain sensor, it is necessary to reduce the number of slots in the annular stator core 20A and reduce the interval between the adjacent protruding magnetic poles 30A. . Furthermore, when the configuration of FIG. 4 is used as a rotation sensor, it is necessary to reduce the interval between the adjacent protruding magnetic poles 30A in order to improve the characteristics of the rotation sensor.

In order to improve the characteristics of the strain sensor or rotation sensor, slots 33A are formed to extend obliquely between the adjacent protruding magnetic poles 30A in the axial direction A of a rotating shaft (not shown). That is, a skew (oblique groove) is formed in the slot 33A with respect to the axial direction A of the annular stator core 20A. By forming the adjacent slots 33A to overlap when viewed from the axial direction A, the adjacent protruding magnetic poles 30A overlap and appear to have no spacing.

Japanese Patent Application Publication No. 2010-115054

In such a stator core structure 10A, generally, in order to insulate the annular stator core 20A, an annular insulating cover (not shown) is provided on the front and back surfaces of the annular stator core 20A. However, since the slots 33A are diagonal grooves, the adjacent slots 33A overlap when viewed from the axial direction A, so when the annular insulating cover is integrally formed with the annular stator core 20A, An undercut occurs between adjacent protruding magnetic poles 30. Therefore, there was a problem in that the annular insulating cover could not be integrally formed with the annular stator core 20A.

The present invention was made to solve these problems, and it is an object of the present invention to provide a stator core structure that can improve sensor characteristics without overlapping adjacent slots when viewed from the axial direction of the rotating shaft. purpose.

In order to solve the above problems, a stator core structure according to the present invention includes an annular stator core, a plurality of protruding magnetic poles that protrude inward at predetermined angular intervals on the inner surface of the annular stator core, and a plurality of protruding magnetic poles that protrude inward at predetermined angular intervals. A flange formed at a tip, a slot formed between each of the protruding magnetic poles, an annular insulating cover integrally provided to cover the annular stator core and the protruding magnetic poles , and integrally with the annular insulating cover. , a first lug formed at the upper part of the brim in contact with the brim, and a second lug formed integrally with the annular insulating cover and in contact with the brim at the lower part of the brim. and a stator core structure in which a rotating shaft is provided coaxially with the annular stator core, wherein the slot is formed obliquely with respect to the rotating shaft, and the slot is formed with respect to the adjacent slot. The flange portions are formed to be separated from each other when viewed from the axial direction of the rotating shaft, the flange portions are formed to overlap with the adjacent flange portions when viewed from the axial direction of the rotating shaft , and the first ear portion is formed so as to overlap the adjacent flange portions when viewed from the axial direction of the rotating shaft. It is characterized in that it is formed apart from the second ear portion of the matching collar portion when viewed from the axial direction of the rotating shaft.

The collar portion has a first ear portion integrally formed with the annular insulating cover at an upper portion, a second ear portion integrally formed with the annular insulating cover at a lower portion, and a first ear portion formed integrally with the annular insulating cover. may be formed to be spaced apart from the second ear portions of the adjacent collar portions when viewed from the axial direction of the rotating shaft.

Since the stator core structure according to the present invention is configured as described above, the following effects can be obtained.
That is, the slot is formed in a diagonal direction with respect to the rotation shaft, the slot is formed to be spaced apart from the adjacent slot when viewed from the axial direction of the rotation shaft, and the flange is formed in a direction oblique to the rotation shaft. Since the slots are formed so as to overlap the flange when viewed from the axial direction of the rotating shaft, the characteristics of the sensor can be improved without overlapping adjacent slots when viewed from the axial direction of the rotating shaft.

1 is a schematic diagram of a stator core structure according to an embodiment of the present invention. FIG. 2 is a plan view of the stator core structure shown in FIG. 1; FIG. 2 is a developed view of the protruding magnetic pole shown in FIG. 1; 1 is a schematic diagram of a conventional stator core structure.

Embodiments of the present invention will be described below with reference to FIGS. 1 to 3 of the accompanying drawings. Note that the same or equivalent parts as in the conventional example will be described with the same reference numerals.
FIG. 1 is a schematic diagram of a stator core structure 10 according to an embodiment of the invention. This stator core structure 10 is used for a strain sensor, a rotation sensor, or the like. The stator core structure 10 has a ring-shaped stator core 20 formed by laminating a plurality of electromagnetic steel plates. The annular stator core 20 has protruding magnetic poles 30 formed to protrude inward at predetermined angular intervals in the circumferential direction. In this embodiment, a total of four protruding magnetic poles 30 are provided at every 90 degrees. A rotating shaft (not shown) is provided inside the protruding magnetic pole 30 when the stator core structure 10 is used as a strain sensor, and a rotary shaft (not shown) that is rotatable together with the rotating shaft is provided when the stator core structure 10 is used as a rotation sensor. A rotor is provided.

The protruding magnetic pole 30 has a base 31 that protrudes from the annular stator core 20, and a flange 32 that is formed at the tip of the base 31 to be wider than the base 31. The flange portion 32 is formed in an arc shape along the circumferential direction of the annular stator core 20 . Further, when forming the annular stator core 20, by laminating the electromagnetic steel plates in a direction oblique to the axial direction A of the rotating shaft, that is, by applying a skew, the protruding magnetic poles 30 are stacked in a direction oblique to the axial direction A of the rotating shaft. It is formed. A slot 33 is formed between each of the adjacent protruding magnetic poles 30 . Since the protruding magnetic pole 30 is formed obliquely with respect to the axial direction A, the slot 33 is formed as a skewed groove extending obliquely with respect to the axial direction A, that is, an oblique groove. In this embodiment, the protruding magnetic poles 30 and the slots 33 are formed to extend obliquely to the left toward the upper side of the stator core structure 10.

In order to insulate the annular stator core 20, an annular insulating cover 50, which is an insulator, is provided on the front and back surfaces of the annular stator core 20. The annular insulating cover 50 has a first annular insulating cover portion 40 provided on the upper surface of the annular stator core 20 and a second annular insulating cover portion 40a provided on the lower surface of the annular stator core 20. Note that the annular insulating cover 50 is composed of a first annular insulating cover part 40 and a second annular insulating cover part 40a, which are integrally molded with the annular stator core 20 or are formed separately. Here, a case is shown in which the first annular insulating cover part 40 and the second annular insulating cover part 40a are integrally molded with the annular stator core 20. The annular stator core 20 including the protruding magnetic poles 30 is sandwiched between molds from the axial direction A of the rotating shaft, that is, from the vertical direction, and is integrally molded with the first annular insulating cover part 40 and the second annular insulating cover part 40a. Ru. On the upper part of the annular stator core 20 and the first annular insulating cover part 40, transition posts 42 for connecting wires of the stator windings (not shown) are formed upward at the same predetermined intervals as the protruding magnetic poles 30. . After the annular insulating cover 50 is provided, a winding (not shown) is wound around the protruding magnetic pole 30.

A terminal holding portion 60 integrally formed with the first annular insulating cover portion 40 is provided on the radially outer side of the annular stator core 20 . The terminal holding portion 60 is formed with terminal pins 61 for connecting the stator core structure 10 to an external device, and guide pins 62 for guiding wiring between the windings and the terminal pins 61.

FIG. 2 is a plan view of the stator core structure 10 shown in FIG. 1. FIG. 3 is a schematic exploded view of two adjacent protruding magnetic poles 30 shown in FIGS. 1 and 2 viewed from inside the annular stator core 20. FIG. As shown in FIGS. 2 and 3, a magnetic pole face 34 is provided at the tip of the protruding magnetic pole 30, with the annular stator core 20 exposed from the annular insulating cover 50. As shown in FIGS. A first ear portion 40A is formed integrally with the first ring-shaped insulating cover portion 40 on the upper portion of the magnetic pole face 34. As shown in FIG. Furthermore, a second lug 40B is formed at the lower part of the magnetic pole face 34 and is integrally formed with the second annular insulating cover portion 40a. That is, the annular insulating cover 50, the first ear portion 40A, and the second ear portion 40B are integrally formed. In addition, on both sides of the magnetic pole surface 34 along the axial direction A, there are provided the above-mentioned grooves that protrude inwardly from the surfaces of the first and second ear portions 40A and 40B of the first and second annular insulating cover portions 40 and 40a. The magnetic pole surface 34 forms first and second protruding step portions 34a and 34b. The protruding step portions 34a and 34b are configured to be chucked to a core within a mold during injection molding.

As shown in FIG. 3, each of the base parts 31 of the protruding magnetic poles 30 is formed at a distance B so as not to overlap with the adjacent base parts 31 when the stator core structure 10 is viewed from the axial direction A. There is. As a result, the slots 33 are formed so as not to overlap with the adjacent slots 33 when viewed from the axial direction A, that is, the slots 33 are formed to be spaced apart from the adjacent slots 33 when viewed from the axial direction A. .

Each of the flanges 32 of the protruding magnetic pole 30 is formed to overlap with the adjacent flanges 32 when viewed from the axial direction A. The first ear portion 40A and the second ear portion 40B are not formed in the range C where the adjacent collar portions 32 overlap. That is, when viewed from the axial direction A, the first ear portion 40A is shaped so as not to overlap the second ear portion 40B of the adjacent collar portion 32, and the second ear portion 40B is It is shaped so as not to overlap with the first ear portion 40A of the collar portion 32. That is, the first ear portion 40A is formed to be spaced apart from the second ear portion 40B of the adjacent collar portion 32 when viewed from the axial direction A of the rotation shaft. The first ring-shaped insulation cover part 40 and the second ring-shaped insulation cover part 40a are not formed on the ends 32a and 32b of the collar part 32, and the collar part 32 is exposed.

Next, the effect of using the stator core structure 10 of this embodiment instead of using the conventional stator core structure will be explained.
In conventional strain sensors that use a stator core structure in which windings are wound around protruding magnetic poles, reducing the number of slots reduces the proportion of air gaps in the entire magnetic circuit between each protruding magnetic pole, improving sensitivity. However, if the number of slots is simply reduced and the slots are arranged at equal intervals around the entire circumference of the annular stator core structure, the intervals between the respective protruding magnetic poles will become large. As a result, the magnetic properties of the protruding magnetic pole portion and the slot portion are significantly different, and the accuracy of the strain sensor is reduced because it is more influenced by the eccentricity of the strain sensor, variations in the characteristics of the rotating shaft, and the like.

In addition, in conventional rotation sensors that use a stator core structure in which windings are wound around protruding magnetic poles, the number of slots itself does not have a large effect on accuracy, but due to the difference in magnetic properties between the protruding magnetic pole parts and the slot parts, the rotor The shape characteristics of are detected as errors.

In a strain sensor and a rotation sensor using a conventional stator core structure in which a winding is wound around such a protruding magnetic pole, as shown in FIG. On the other hand, there is a method in which the slots 33A are stacked in a diagonal direction and the slots 33A are formed into oblique grooves that overlap with the adjacent slots 33A when viewed from the axial direction A of the rotating shaft. With this method, when viewed along the axial direction A of the rotating shaft, the protruding magnetic poles 30A overlap with the adjacent protruding magnetic poles 30A, so that it appears that there is no gap between the protruding magnetic poles 30A. Therefore, the difference in magnetic properties between the protruding magnetic pole 30A portion and the slot 33A portion is reduced, and the accuracy of the strain sensor and rotation sensor is improved. However, since an undercut occurs due to the overlapping of the adjacent protruding magnetic poles 30A when viewed from the axial direction A of the rotating shaft, it is not possible to integrally mold an annular insulating cover (not shown) to the annular stator core 20A. Can not.

On the other hand, in the stator core structure 10 of this embodiment, the slots 33 are formed so as not to overlap with the adjacent slots 33 when viewed from the axial direction A, but the flange of the protruding magnetic pole 30 32 is formed so as to overlap the adjacent flange portions 32 when viewed from the axial direction A. Therefore, even if the adjacent slots 33, which are oblique grooves, do not overlap when viewed from the axial direction A, and the adjacent protruding magnetic poles 30 do not overlap when viewed from the axial direction A, the adjacent protruding magnetic poles 30 do not overlap when viewed from the axial direction A. Similar to the case where they overlap, the difference in magnetic properties between the protruding magnetic pole 30 portion and the slot 33 is reduced. This improves the accuracy of the strain sensor and rotation sensor.

Furthermore, when viewed from the axial direction A, the first ear portion 40A of the first ring-shaped insulating cover portion 40 is formed so as not to overlap the adjacent second ear portion 40B, and the second ring-shaped Since the second ear portion 40B of the insulating cover portion 40a is formed so as not to overlap the adjacent first ear portion 40A, even if the slot 33 is an oblique groove, the first ring-shaped insulating cover portion 40 and An undercut does not occur in the second annular insulating cover portion 40a, and the annular insulating cover 50 can be integrally formed with the annular stator core 20.

In this way, the annular stator core 20, a plurality of protruding magnetic poles 30 protruding inwardly at predetermined angular intervals on the inner surface of the annular stator core 20, and the flange portion formed at the tip of the protruding magnetic poles 30. 32, the slot 33 formed between each of the protruding magnetic poles 30, and the annular insulating cover 50 integrally provided to cover the annular stator core 20 and the protruding magnetic poles 30, the annular stator core 20 The stator core structure has a stator core structure in which the rotating shaft is provided coaxially with respect to the rotating shaft, and the slot 33 is formed obliquely to the rotating shaft, and the slot 33 is formed in the direction of the rotating shaft with respect to the adjacent slot 33. The flange portions 32 are formed to be separated from each other when viewed from the axial direction A, and the flange portions 32 are formed so as to overlap the adjacent flange portions 32 when viewed from the axial direction A of the rotating shaft. It is possible to provide a stator core structure that can improve the characteristics of a strain sensor or a rotation sensor without overlapping the adjacent slots 33 when viewed from A.

Further, the flange portion 32 has the first ear portion 40A formed integrally with the annular insulating cover 50 at the upper portion, and the second ear portion 40B formed integrally with the annular insulating cover 50 at the lower portion. Since the first ear portion 40A is formed to be spaced apart from the second ear portion 40B of the adjacent collar portion 32 when viewed from the axial direction A of the rotating shaft, the slot 33 is Even if the groove is an oblique groove, the first ear portion 40A and the second ear portion 40B can be integrally formed with the annular stator core 20.

In this embodiment, the annular stator core 20 is provided with four protruding magnetic poles 30, but the number of protruding magnetic poles 30 may be any number greater than or equal to two. Furthermore, although the protruding magnetic poles 30 and the slots 33 are formed to extend diagonally to the left toward the upper side of the stator core structure 10, they may be formed to extend diagonally to the right. Furthermore, although the stator core structure 10 has been used in strain sensors and rotation sensors, it may be used in other types of sensors and devices having the protruding magnetic poles 30.

Note that the stator structure of the strain sensor according to the present invention is as follows. That is, the annular stator core 20, a plurality of protruding magnetic poles 30 protruding inwardly at predetermined angular intervals on the inner surface of the annular stator core 20, and the flange 32 formed at the tip of the protruding magnetic poles 30. , the slot 33 formed between each of the protruding magnetic poles 30, and the annular insulating cover 50 integrally provided to cover the annular stator core 20 and the protruding magnetic pole 30; The stator core structure is such that the rotating shaft is provided coaxially with the rotating shaft, and the slot 33 is formed obliquely with respect to the rotating shaft, and the slot 33 is formed in the axial direction of the rotating shaft with respect to the adjacent slot 33. The flange portions 32 are formed to be separated from each other when viewed from A, and the flange portions 32 are formed so as to overlap the adjacent flange portions 32 when viewed from the axial direction A of the rotating shaft, and the flange portions 32 has the first ear portion 40A integrally formed with the annular insulating cover 50 at an upper portion, the second ear portion 40B integrally formed with the annular insulating cover 50 at a lower portion, and The first ear portion 40A is formed to be spaced apart from the second ear portion 40B of the adjacent collar portion 32 when viewed from the axial direction A of the rotating shaft.

The stator core structure according to the present invention includes an annular stator core, a plurality of protruding magnetic poles protruding inward at predetermined angular intervals on the inner surface of the annular stator core, a flange formed at the tip of the protruding magnetic poles, and each protruding magnetic pole. The stator core structure includes a slot formed between the annular stator core and an annular insulating cover integrally provided to cover the annular stator core and the protruding magnetic pole, and the annular stator core has a rotation axis coaxial with the annular stator core. The slot is formed in a diagonal direction with respect to the rotation axis, and the slot is formed at a distance from adjacent slots when viewed from the axial direction of the rotation shaft, and the flange is formed in a direction oblique to the rotation axis with respect to the adjacent flange. Since the slots 33 are formed so as to overlap when viewed from the axial direction of the rotating shaft, the characteristics of the sensor can be improved without overlapping the adjacent slots 33 when viewed from the axial direction A of the rotating shaft.

20 Annular stator core 30 Projecting magnetic pole 32 Flange 33 Slot 40A First ear 40B Second ear 50 Annular insulating cover A Axial direction

Claims (2)

a ring-shaped stator core (20);
A plurality of protruding magnetic poles (30) protruding inward at predetermined angular intervals on the inner surface of the annular stator core (20);
a flange (32) formed at the tip of the protruding magnetic pole (30);
a slot (33) formed between each of the protruding magnetic poles (30);
a ring-shaped insulating cover (50) integrally provided to cover the ring-shaped stator core (20) and the protruding magnetic pole (30) ;
a first lug (40A) formed integrally with the annular insulating cover (50) and in contact with the flange (32) at the upper part of the flange (32);
A second lug (40B) formed integrally with the ring-shaped insulating cover (50) at a lower portion of the flange (32) in contact with the flange (32);
Equipped with
A stator core structure in which a rotation axis is provided coaxially with the annular stator core (20),
The slot (33) is formed obliquely with respect to the rotating shaft, and the slot (33) is spaced apart from adjacent slots (33) when viewed from the axial direction (A) of the rotating shaft. formed,
The flange portion (32) is formed so as to overlap the adjacent flange portions (32) when viewed from the axial direction (A) of the rotation shaft ,
The first ear portion (40A) is formed to be spaced apart from the second ear portion (40B) of the adjacent collar portion (32) when viewed from the axial direction (A) of the rotation shaft. Characteristic stator core structure. The stator core structure according to claim 1, wherein the annular stator core (20), the protruding magnetic pole (30), and the annular insulating cover (50) are integrally molded.

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