Stator structure and rotary transformer

Abstract

The stator structure (1) of the embodiment comprises a stator core (10), the stator core (10) having an annular main body (11) and a plurality of teeth (12) extending in the radial direction of the main body (11) and arranged in the circumferential direction of the main body (11). The main body (11) comprises: a plurality of long holes (13) formed in an arc shape along the circumferential direction of the main body (11) and arranged in the circumferential direction of the main body (11); and a plurality of hole portions (14) arranged in the circumferential direction of the main body (11) between the plurality of teeth (12) and the plurality of long holes (13) in the radial direction of the main body (11). At least one of the hole portions (14) is arranged between a beam portion (15) provided between adjacent long holes (13) and a tooth (12) close to the beam portion (15).

Description

[0001] This application is a divisional application of the invention patent application with Chinese application number 201980007433.0 (the name of the original application is “Stator structure and rotary transformer”, and the application date of the original application is January 15, 2019). Technical Field

[0002] The invention relates to a stator structure and a rotary transformer. Background Art

[0003] Conventionally, there is a known rotary transformer for detecting the rotation angle of a rotary electric machine such as a motor or a generator. Such a rotary transformer includes, for example, a stator core having a plurality of teeth extending from the inner circumference of a main body formed in an annular shape toward the center, and a rotor disposed on the inner side of such a stator core opposite to the teeth. Windings are wound around the teeth via an insulator, and such windings are composed of an excitation winding to which an excitation current is supplied from the outside and two output windings that output two-phase signals according to the rotation angle of the rotor.

[0004] On the other hand, when current flows through the winding of the rotating motor, which is the rotation angle detection object of the rotary transformer, leakage magnetic flux from the winding of the rotating motor sometimes enters the output winding of the stator structure. As a result, the leakage magnetic flux overlaps with the waveform of the signal output from such an output winding as a noise component, and there is a concern that the angle detection accuracy of the rotary transformer will be reduced. Therefore, in Patent Document 1, a rotary transformer is proposed, which is configured such that a plurality of arc-shaped openings are formed along the circumferential direction on the main body of the stator core, and the magnetic resistance of the outer edge of the stator core is increased by the arc-shaped openings, so that the leakage magnetic flux is not easy to reach the inner side of the stator core, thereby preventing the magnetic effect on the winding wound on the protruding magnetic pole as the tooth.

[0005] Patent Document 1: Japanese Patent Application Publication No. 2014-150703

[0006] However, in the rotary transformer described in Patent Document 1, the leakage magnetic flux penetrates into the inner area of ​​the stator core through the gap between the adjacent arc-shaped openings, i.e., the beam portion, and has a greater impact on the output winding wound around the teeth, i.e., the protruding magnetic poles, that are close to such beam portions. On the other hand, the impact on the output winding wound around the protruding magnetic poles that are far from the beam portion becomes smaller. Therefore, depending on the position of the protruding magnetic pole, the impact on the output winding wound around the protruding magnetic pole differs, and as a result, a difference in noise components is generated at each protruding magnetic pole, so there is a concern that the angle detection accuracy of the rotary transformer will be reduced. Summary of the invention

[0007] The present invention is completed in view of the above content, and its purpose is to provide a stator structure and a rotary transformer that can reduce the difference in the influence of magnetic flux invading from the outer circumference of the stator structure to the inner circumference on the winding wound on the teeth and suppress the reduction in angle detection accuracy caused by external magnetic flux.

[0008] In order to solve the above-mentioned problems and achieve the purpose, a stator structure according to one embodiment of the present invention includes a stator core having an annular main body and a plurality of teeth extending in the radial direction of the main body and arranged in the circumferential direction of the main body. The main body has: a plurality of long holes formed in an arc shape along the circumferential direction of the main body and arranged in the circumferential direction of the main body; and a plurality of hole portions arranged in the circumferential direction of the main body between the plurality of teeth and the plurality of long holes in the radial direction of the main body. At least one of the hole portions is arranged between a beam portion provided between adjacent long holes and the tooth close to the beam portion.

[0009] According to one aspect of the present invention, it is possible to suppress a decrease in angle detection accuracy due to magnetic flux intruding from the outer circumference side of the stator structure to the inner circumference side. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 It is a plan view showing the structure of the stator structure according to the embodiment.

[0011] Figure 2 It is a cross-sectional view showing a state where the resolver according to the embodiment is mounted on a rotating electrical machine.

[0012] Figure 3 It is a plan view showing the stator core according to the embodiment.

[0013] Figure 4 This is a diagram for explaining the flow of leakage magnetic flux penetrating from the outer circumference side to the inner circumference side of the stator core according to the embodiment.

[0014] Figure 5 It is a plan view showing a stator core according to a modification of the embodiment.

[0015] Figure 6 This is a diagram for explaining the flow of leakage magnetic flux penetrating from the outer peripheral side to the inner peripheral side of the stator core according to the modification of the embodiment. DETAILED DESCRIPTION

[0016] Hereinafter, the stator structure and the rotary transformer involved in the embodiment will be described with reference to the accompanying drawings. In addition, the use of the stator structure and the rotary transformer is not limited by the embodiment described below. In addition, the accompanying drawings are schematic, and it should be noted that the relationship between the dimensions of each element, the ratio of each element, etc. are sometimes different from the actual. In addition, sometimes the drawings also contain parts with different dimensional relationships and ratios.

[0017] (Stator structure and resolver structure)

[0018] First, refer to Figure 1 as well as Figure 2 The configurations of the stator structure 1 and the resolver 3 according to the embodiment will be described. Figure 1 It is a plan view showing the structure of the stator structure 1 according to the embodiment.

[0019] By Figure 1 The rotor 2 is arranged inside the stator structure 1 shown in the figure, thereby obtaining the rotary transformer 3 involved in the embodiment. The rotary transformer 3 involved in the embodiment is a VR (Variable Reluctance) type rotary transformer. Figure 1 As shown, the resolver 3 is an inner rotor type resolver, and the rotor 2 is arranged inside the stator structure 1 .

[0020] Figure 2 1 is a cross-sectional view showing a state where the rotary transformer 3 according to the embodiment is mounted on the rotary electric machine 100. The rotor 2 is fixed to the output shaft 101 of the rotary electric machine 100 and rotates with the rotation of the output shaft 101. The rotary electric machine 100 is, for example, an AC motor, an AC generator, an AC motor generator, etc., and includes an output shaft 101, a rotor 102 fixed to the output shaft 101, and a stator structure 104 having a winding 103.

[0021] For example, when rotating electrical machine 100 is an AC motor, winding 103 of stator structure 104 is a field winding. When field current flows through such field winding, rotor 102 of rotating electrical machine 100 rotates, and output shaft 101 rotates along with the rotation of rotor 102 .

[0022] In addition, the stator structure 1 is fixed to the housing 105 of the rotating electrical machine 100 by bolts 110. The bolts 110 are formed of, for example, an iron material.

[0023] return Figure 1 The outer peripheral surface of the rotor 2 is formed into a non-circular shape that is concave and convex in the radial direction. Figure 1The rotor 2 shown has three convex portions 2a on the outer peripheral surface, and shows a case where the axis angle of the rotor 2 is 3X. The axis angle of the rotor 2 may be 1X, 2X, or 4X or more.

[0024] The rotor 2 has a laminated structure in which a plurality of cores are laminated, each of which is produced by press-working steel plates such as electromagnetic steel plates made of a soft magnetic material.

[0025] The stator structure 1 includes a stator core 10 , an insulator 20 , a winding 30 , a terminal block 40 , and a conductor holding portion 50 .

[0026] The stator core 10 has a laminated structure formed by laminating a plurality of steel plates such as electromagnetic steel plates. The stator core 10 has a main body 11 and a plurality of teeth 12. The main body 11 is annular, and in the embodiment, is an annular shape. The plurality of teeth 12 extend from the inner circumference of the main body 11 toward the center of the main body 11 (i.e., radially).

[0027] In addition, the following Figure 1 as well as Figure 2 As shown, the radial direction, axial direction, and circumferential direction of the stator core 10 are defined and described. Here, the "radial direction" is a direction orthogonal to the rotation axis of the rotor 2 rotating inside the stator core 10, the "axial direction" is a direction consistent with the axial direction of the rotation axis of the rotor 2, and the "circumferential direction" is a direction consistent with the rotation direction of the rotor 2.

[0028] In addition, a plurality of long holes 13 and a plurality of hole portions 14 are formed in the main body portion 11 of the stator core 10. The plurality of long holes 13 and the plurality of hole portions 14 are formed concentrically with each other. The detailed structure of the stator core 10 will be described later.

[0029] The insulator 20 is an insulating member, and is formed by, for example, injection molding of an insulating resin. The insulator 20 is formed by, for example, insert molding such that the stator core 10 is embedded inside, and covers the stator core 10 from both sides in the axial direction.

[0030] The winding 30 includes a conductive wire and an insulating film covering the conductive wire. The conductive wire is, for example, a metal wire such as a copper wire, an aluminum wire, or a brass wire. The winding 30 is wound around the plurality of teeth 12 via the insulator 20 to form a plurality of coils 31 .

[0031] Such coil 31 is composed of an excitation winding and an output winding. In addition, the output winding of coil 31 is composed of a sin-phase output winding that outputs a sin-phase output signal and a cos-phase output winding that outputs a cos-phase output signal.

[0032] The terminal base portion 40 is formed on the insulator 20 and extends radially outward from the insulator 20. The terminal base portion 40 supports a plurality of (six in the embodiment) terminals 41.

[0033] The terminal 41 is a conductive member such as metal, and has a winding portion 41a protruding in the axial direction from the terminal base 40 at one end. The end of the winding 30 constituting the corresponding coil 31 is wound around the winding portion 41a.

[0034] For example, the winding start and end of the excitation winding, the winding start and end of the sin phase output winding, the winding start and end of the sin phase output winding, the winding start and end of the cos phase output winding, and the winding end of the cos phase output winding are respectively wound on the winding portions 41a of the six terminals 41.

[0035] Furthermore, by performing TIG (Tungsten Inert Gas) welding, for example, on the winding portion 41 a around which the end of the winding 30 is wound, the winding 30 and the winding portion 41 a can be electrically connected.

[0036] In addition, the other end of the terminal 41 is received in the wire holding portion 50 extending radially outward from the terminal base portion 40. Figure 1 As shown, a plurality of slot-shaped insertion portions 51 are formed in such a wire holding portion 50 , and wires (not shown) extending from an external device (not shown) are inserted into and held in such insertion portions 51 .

[0037] Since the other end of the terminal 41 is exposed in the insertion portion 51, the lead wire and the terminal 41 can be electrically connected by inserting the lead wire into the insertion portion 51. For example, the lead wire and the terminal 41 can be electrically connected by performing resistance welding on the contact portion between the lead wire and the terminal 41.

[0038] like Figure 1 As shown, the winding 30 is guided by the guide portion 42 and extends along a predetermined path from the coil 31 toward the winding portion 41a. The guide portion 42 is, for example, a pin-shaped guide pin erected at a predetermined position of the terminal block 40. In addition, the guide portion 42 is independently provided for each of the plurality of windings 30 wound around the plurality of winding portions 41a.

[0039] In order to reduce the influence of thermal expansion caused by temperature change, a slack portion is formed between the coil 31 and the winding portion 41a in the winding 30. Such a slack portion is formed by inserting slack pins (not shown) through a plurality of insertion holes 43 formed in the terminal block 40, and the winding 30 is hooked on such slack pins while being wound around the winding portion 41a, and then the slack pins are pulled out from the insertion holes 43.

[0040] (Details of stator core)

[0041] Next, refer to Figure 3 as well as Figure 4The stator core 10 according to the embodiment will be described in detail. Figure 3 is a plan view showing a stator core 10 according to the embodiment. Figure 3 In the example shown, the number of teeth 12 is 14, the number of arc-shaped long holes 13 is 7, and the number of holes 14 is 28, but the numbers of teeth 12, long holes 13, and holes 14 are not limited to the above numbers.

[0042] The long hole 13 can be used as an insertion hole for inserting a bolt 110 for fixing the rotary transformer 3 to the housing 105 of the rotary electric machine 100. The long hole 13 penetrates in the axial direction and is formed in an arc shape along the circumferential direction of the main body 11. A plurality of long holes 13 are formed rotationally symmetrically with respect to the center of the main body 11 and are arranged along the circumferential direction of the main body 11.

[0043] For example, Figure 3 As shown, the plurality of long holes 13 are arranged at equal angular intervals along the circumferential direction of the main body 11. In addition, the plurality of long holes 13 do not necessarily need to be arranged at equal angular intervals.

[0044] In addition, a beam portion 15 is provided in the main body 11 between adjacent long holes 13 to connect the inner peripheral portion and the outer peripheral portion of the main body 11 .

[0045] The plurality of teeth 12 are arranged along the circumferential direction on the inner side of the main body 11. The plurality of teeth 12 include: a first tooth 12a located near the beam 15 and a second tooth 12b located away from the beam 15 and located near the long hole 13. In the embodiment, the first teeth 12a and the second teeth 12b are arranged alternately. In addition, an insertion opening 16 as a gap is formed between adjacent teeth 12.

[0046] Here, when Figure 2 When an excitation current flows through the winding 103 of the rotating electrical machine 100 shown, leakage magnetic flux from the winding 103 of the rotating electrical machine 100 may intrude from the outer circumference side to the inner circumference side of the stator structure 1 in the resolver 3 .

[0047] In an embodiment, if Figure 3 As shown, the plurality of holes 14 penetrate in the axial direction and are formed in a circular shape. Furthermore, the plurality of holes 14 are arranged at equal angular intervals along the circumference of the body 11 on the outer peripheral side of the plurality of teeth 12 and between the plurality of teeth 12 and the plurality of long holes 13. In addition, the plurality of holes 14 do not necessarily need to be arranged at equal angular intervals.

[0048] The plurality of holes 14 include a first hole 14a disposed between the first tooth 12a and the beam 15, a second hole 14b disposed between the second tooth 12b and the long hole 13, and a third hole 14c disposed between the socket 16 and the long hole 13. Figure 4 The effects of the plurality of holes 14 will be described.

[0049] Figure 4 This is a diagram for explaining the flow of leakage fluxes M1 and M2 penetrating from the outer circumference to the inner circumference of the stator core 10 according to the embodiment. As described above, since the magnetic resistance of the long hole 13 as a gap is high, the leakage flux M1 penetrating the long hole 13 among the leakage fluxes M1 and M2 penetrating from the outer circumference can be suppressed from penetrating into the long hole 13. On the other hand, the leakage flux M2 penetrating the beam portion 15 is not blocked by the beam portion 15, and therefore penetrates into the region where the plurality of hole portions 14 are formed.

[0050] Furthermore, in an embodiment, if Figure 4 As shown, the first hole portion 14a is arranged between the first tooth 12a and the beam portion 15, so the leakage magnetic flux M2 avoids the first hole portion 14a and enters, and flows toward the first tooth 12a and the second tooth 12b adjacent to the first tooth 12a.

[0051] In the case where the first hole portion 14a is not provided, the leakage magnetic flux M2 that penetrates from the outer peripheral side of the stator core 10 through the beam portion 15 has a greater influence on the coil 31 wound on the first tooth 12a, and the difference between the influence on the coil 31 wound on the second tooth 12b becomes larger. In contrast, in the embodiment, by providing the first hole portion 14a, the influence on the coil 31 wound on the first tooth 12a can be reduced, and the influence on the coil 31 wound on the second tooth 12b can be increased, thereby reducing the difference between the influence on the coil 31 wound on the first tooth 12a and the influence on the coil 31 wound on the second tooth 12b.

[0052] That is, in the embodiment, the influence on the coil 31 wound around the first tooth 12a from the outer peripheral side of the stator core 10 is reduced, and the influence on the coil 31 wound around the second tooth 12b from the outer peripheral side of the stator core 10 is increased, thereby making it possible to reduce the difference between the influence on the coil 31 wound around the first tooth 12a and the influence on the coil 31 wound around the second tooth 12b. As a result, according to the embodiment, it is possible to suppress the reduction in angle detection accuracy caused by the leakage flux M1 and M2 intruding from the outer peripheral side of the stator core 10.

[0053] In the embodiment, the plurality of holes 14 are preferably arranged at equal angular intervals along the circumferential direction of the main body 11. Thus, the difference in the effect of the leakage magnetic fluxes M1 and M2 that infiltrate from the outer circumference of the teeth 12 arranged along the inner circumference as a whole on the coil 31 wound around the teeth 12 can be reduced. Therefore, according to the embodiment, the reduction in angle detection accuracy caused by the leakage magnetic fluxes M1 and M2 that infiltrate from the outer circumference of the stator core 10 can be further suppressed.

[0054] In the embodiment, it is preferable that all the plurality of holes 14 have the same shape. Thus, the hole 14 can be used as a part of the insertion hole 43 for inserting the slack pin. Therefore, according to the embodiment, the insertion hole 43 used to form the slack portion in the winding 30 can be easily formed.

[0055] (Variation Example)

[0056] Next, refer to Figure 5 as well as Figure 6 In the following description, the same reference numerals are given to the same parts as those in the embodiment, and overlapping descriptions may be omitted.

[0057] Figure 5 1 is a plan view showing a stator core 10 according to a modified example of the embodiment. Figure 6 The diagrams are for explaining flows of leakage magnetic fluxes M1 and M2 penetrating from the outer peripheral side of the stator core 10 into the stator core 10 according to the modification of the embodiment.

[0058] like Figure 5 As shown, in the modified example, a first hole portion 14a1 having a shape different from the second hole portion 14b and the third hole portion 14c is formed in the main body portion 11 of the stator core 10. The first hole portion 14a1 of the modified example penetrates in the axial direction and is formed as an arc-shaped long hole along the circumferential direction of the main body portion 11.

[0059] That is, the first hole portion 14a1 of the modified example is formed at a larger angle in the circumferential direction than the first hole portion 14a of the embodiment, so that Figure 6 As shown, the leakage magnetic flux M2 that penetrates the inner peripheral side via the beam portion 15 is blocked by the first hole portion 14a1, so that the influence on the coil 31 wound around the first tooth 12a can be further reduced.

[0060] Thus, the influence of the leakage magnetic flux M2 on the coil 31 wound on the first tooth 12a can be further reduced, and thus the difference between the influence on the coil 31 wound on the first tooth 12a and the influence on the coil 31 wound on the second tooth 12b can be further reduced. Therefore, according to the embodiment, the reduction in angle detection accuracy caused by the leakage magnetic flux M1 and M2 intruding from the outer circumference and inner circumference of the stator core 10 can be further suppressed.

[0061] In the modified example, the plurality of first holes 14a1 are formed rotationally symmetrically with respect to the center of the main body 11. On the other hand, the plurality of first holes 14a1 do not necessarily need to be formed rotationally symmetrically with respect to the center of the main body 11.

[0062] The above describes the embodiment of the present invention, but the present invention is not limited to the above embodiment, and various changes can be made as long as they do not deviate from the main purpose. For example, in the embodiment, the second hole portion 14b and the third hole portion 14c are formed in equal shapes, but the second hole portion 14b and the third hole portion 14c can also be formed in different shapes.

[0063] In addition, in the embodiment, an example is shown in which the long hole 13 is formed in an arc shape, but it can also be formed in a straight line along the circumference of the main body 11, or in a circular shape or a quadrilateral shape. In addition, in the embodiment, an example is shown in which the hole portion 14 is formed in a circular shape, but the hole portion 14 is not limited to a circular shape, and can also be a long hole shape or a quadrilateral shape.

[0064] In the embodiment, an example in which the insulator 20 is integrally formed is shown, but the insulator may be divided into two in the axial direction and the stator core 10 may be sandwiched between the two insulators. Furthermore, in the embodiment, a case in which the present invention is applied to the inner rotor type rotary transformer 3 is shown, but the present invention may also be applied to an outer rotor type rotary transformer.

[0065] As described above, the stator structure 1 according to the embodiment and the modified example includes the stator core 10, which includes the annular main body 11 and the plurality of teeth 12 extending in the radial direction of the main body 11 and arranged in the circumferential direction of the main body 11. The main body 11 includes: a plurality of long holes 13 formed in an arc shape along the circumferential direction of the main body 11 and arranged in the circumferential direction of the main body 11; and a plurality of hole portions 14 arranged in the circumferential direction of the main body 11 between the plurality of teeth 12 and the plurality of long holes 13 in the radial direction of the main body 11. At least one of the hole portions 14 (the first hole portion 14a (14a1)) is arranged between the beam portion 15 provided between the adjacent long holes 13 and the tooth 12 close to the beam portion 15. Thus, it is possible to suppress the reduction in angle detection accuracy caused by the leakage magnetic fluxes M1 and M2 intruding from the outer peripheral side.

[0066] In the stator structure 1 according to the embodiment and the modified example, the plurality of holes 14 are arranged at equal angular intervals along the circumferential direction of the body 11. This can further suppress a decrease in angle detection accuracy caused by leakage magnetic fluxes M1 and M2 intruding from the outer circumference.

[0067] In the stator structure 1 according to the embodiment, all of the plurality of holes 14 have the same shape. This makes it possible to easily form the insertion holes 43 for facilitating the manufacture of the stator core 10 and for forming a slack portion in the winding 30 .

[0068] In addition, in the stator structure 1 according to the modified example, the hole portion (first hole portion 14a1) disposed between the beam portion 15 and the tooth (first tooth 12a) close to the beam portion 15 is larger than the hole portion (second hole portion 14b, third hole portion 14c) not disposed between the beam portion 15 and the tooth (first tooth 12a) close to the beam portion 15. Thus, the reduction in angle detection accuracy caused by the leakage magnetic fluxes M1 and M2 intruding from the outer peripheral side of the stator core 10 can be further suppressed.

[0069] The number of third holes 14c formed between the first hole 14a and the second hole 14b is not limited to one, and the number can be determined in consideration of the influence of leakage flux penetrating from the beam 15 of the stator core 10 to the inner circumference of the stator core 10 .

[0070] In addition, the present invention is not limited by the above-mentioned embodiment. The mode of appropriately combining the above-mentioned various components and constituting is also included in the present invention. In addition, further effects and modifications can be easily derived by those skilled in the art. Therefore, the wider mode of the present invention is not limited to the above-mentioned embodiment, and various changes can be made.

[0071] Description of Reference Numerals

[0072] 1... stator structure; 2... rotor; 3... rotary transformer; 10... stator core; 11... main body; 12... teeth; 12a... first tooth; 12b... second tooth; 13... long hole; 14... hole; 14a, 14a1... first hole; 14b... second hole; 14c... third hole; 15... beam; 16... socket; 20... insulator; 30... winding; 31... coil; 40... terminal block; 50... wire holding portion; 100... rotating electrical machine; M1, M2... leakage flux.

Claims

1. A stator structure of a rotary transformer, characterized in that: A stator core is provided, the stator core having an annular main body, a plurality of teeth extending in a radial direction of the main body and arranged in a circumferential direction of the main body, and a socket formed between adjacent teeth. The main body has a plurality of holes arranged along the circumferential direction of the main body on the outer peripheral side of the plurality of teeth. The plurality of holes have: a first hole portion group arranged at a position overlapping with the teeth in a radial direction so as to be close to the root of the teeth; and The second hole portion group is arranged close to the socket and at a position overlapping the socket in a radial direction.

2. The stator structure of the rotary transformer according to claim 1, characterized in that: All of the plurality of holes have the same shape.

3. The stator structure of the rotary transformer according to claim 2, characterized in that: The plurality of hole portions have a circular shape.

4. The stator structure of the rotary transformer according to claim 3, characterized in that: The plurality of holes are arranged at equal intervals along the circumferential direction.

5. The stator structure of the rotary transformer according to claim 3, characterized in that: The plurality of holes are arranged at unequal intervals along the circumferential direction.

6. The stator structure of the rotary transformer according to claim 1 or 2, characterized in that: The stator core includes an insulator, a terminal base portion extending radially outward from an outer circumference of the insulator, a plurality of terminals provided on the terminal base portion, and a coil wound around the teeth via the insulator. The ends of the coil are connected to the plurality of terminals. The terminal block is formed with an insertion hole for inserting a pin forming a slack portion at the coil end. The plurality of hole portions constitute a portion of the insertion hole.

7. The stator structure of the rotary transformer according to claim 1 or 2, characterized in that: The second hole portion group, which is arranged at a position overlapping the socket in a radial direction so as to be close to the socket, is arranged at a substantially central position of the socket.

8. The stator structure of the rotary transformer according to claim 1, characterized in that: The present invention further includes a third hole portion group, which is located on the outer peripheral side of the plurality of hole portions and is formed to extend along a position overlapping with both the teeth and the socket in the radial direction.

9. The stator structure of the rotary transformer according to claim 8, characterized in that: The third hole group is arranged on concentric circles along the circumferential direction.

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