JP2013208021A - Stator core - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a stator core capable of increasing a winding amount by securing a region where a winding is actually wound as widely as possible.SOLUTION: A stator core 21 is configured such that division cores 21A each including a core body 21B, a teeth portion 21a, and a collar portion 21c at a radially inner end of the teeth portion 21a and split in a peripheral direction so as to have one teeth portion 21a respectively, each include a division core body 21b, the teeth portion 21a, and the collar portion 21c; a slot 21s housing a winding 23 wound around the teeth portion 21c is defined with the division core body 21b, teeth portion 21a, and collar portion 21c; and a radial inner side face 21g of the division core body 21b comprises a flat surface orthogonal to a center line S of the teeth portion 21a. The stator core 21 is provided with a groove 21j housing a starting line 23a of the winding 23 at a position closest to the root of the teeth portion 21c on the radial inner side face 21g of the division core body 21b defining the slot 21s.

Description

  The present invention relates to a stator core used in an inner rotor type motor in which a stator is provided on a motor outer peripheral portion and a rotor is provided in a motor central portion.

  For example, in an inner rotor type IPM motor, a stator (stator) around which a coil (winding) is wound is provided on the outer periphery of the motor, and a rotor (rotor) having a permanent magnet is provided at the motor center. Is provided. The stator is configured by fixing a stator core (stator core) in which a coil is wound around each tooth portion via an insulator to the inner periphery of the stator housing.

This type of motor can improve the motor performance as the density (space factor) of the winding wound around the tooth portion is higher. Therefore, in order to easily increase the winding amount with respect to the tooth portion, there is a stator core including the tooth portion divided in the circumferential direction (for example, see Patent Document 1).
In this way, since the stator core can be assembled in an annular shape after winding the winding for each divided core, it is easy to secure a sufficient amount of winding, and the space factor is reduced. Can be increased. Moreover, since the winding can be wound around the tooth portion by rotating the split core, the efficiency of the winding work can be improved.

FIG. 10 is a cross-sectional view of the configuration of one split core in an example of a conventional split core type stator core as seen from the motor axial direction.
A stator core (not shown) composed of the divided cores 421A includes an annular core body 420 that is fixed to the inner periphery of a stator housing (not shown) and a core body 420 that is arranged at equal intervals in the circumferential direction. A plurality of teeth portions 421a formed to extend inward in the radial direction, and flange portions 421c formed to extend at both ends in the circumferential direction at the radially inner ends of the teeth portions 421a. Are divided into a plurality of equal parts in the circumferential direction.

  Each of the divided cores 421 is provided with a split core body 421b, a teeth portion 421a, and a flange portion 421c that constitute the core body 420 by being connected in an annular shape. In addition, a slot 421s that accommodates the winding 23 wound around the tooth portion 421a via an insulator (not shown) is defined by the divided core main body 421b, the tooth portion 421a, and the flange portion 421c.

  In this case, the radially outer side surface 421f of the split core main body 421b is configured as an arc surface in accordance with the inner peripheral surface of the stator housing, and the radial inner side surface 421g of the split core main body 421b moves in a complicated manner. In order to be able to perform winding even if it does not, it is comprised by the flat surface orthogonal to the center line S of the width direction of the teeth part 421a. In addition, convex connecting portions 421d and concave connecting portions 421e are provided at both ends in the circumferential direction of the split core main body 421b, respectively, and the convex connecting portions 421d and concave shapes of the split core main bodies 421b adjacent in the circumferential direction are provided. By fitting the connecting portion 421e, the split core main body 421b is connected in an annular shape to form an annular core main body.

  Further, the radially inner side surface 421h of the flange portion 421c is formed in a circular arc shape corresponding to the outer diameter of the rotor, and the radially outer surface 421i facing the slot 421s goes in a direction away from the tooth portion 421a in the circumferential direction. It is formed in the inclined surface inclined toward the inner side in the radial direction.

International Publication No. 2006/120975

  By the way, in the conventional split core 421A, the region (winding region) around which the winding 23 is wound is divided into the side surface in the width direction (circumferential side surface) of the tooth portion 421a and the radially inner side surface 421g of the split core main body 421b. And the cross-sectional area of the slot 421s defined by the radially outer side surface of the flange portion 421c, the width of the teeth portion 421a cannot be reduced because it is necessary to consider the saturation magnetic flux density. There is a problem that it is difficult to further enlarge the size of the slot 421 s to increase the winding area because the radially inner side surface 421 g of the split core body 421 b is a flat surface.

  The present invention has been made in consideration of the above circumstances, and the main dimensions of the radially inner side surface of the split core body, the width side surface of the teeth portion, and the radially outer side surface of the collar portion that determine the size of the slot are almost changed. In other words, at the level that does not affect the magnetic path, it is possible to secure a wide area where the winding can actually be wound as much as possible, and to increase the winding amount. It is an object of the present invention to provide a stator core that can be improved.

In order to solve the above-mentioned problem, the invention described in claim 1 includes an annular core body and a plurality of circular core bodies formed at equal intervals in the circumferential direction and extending radially inward from the core body. Each tooth portion is provided with a heel portion formed to extend to both sides in the circumferential direction at the radially inner tip of each tooth portion, and is divided into a plurality of portions in the circumferential direction so as to have one each of the teeth portions. Each of the split cores is provided with a split core main body that constitutes the core main body by being connected in an annular shape, the tooth portion, and the flange portion, and is wound around the tooth portion via an insulator. A slot that accommodates the winding to be formed is defined by the split core main body, the teeth portion, and the flange portion, and the radially inner side surface of the split core main body is a flat surface that is orthogonal to the center line of the teeth portion. Constructed stator (A) a notch that widens the accommodation area of the winding on at least one of a radially inner side surface formed by a flat surface of the split core body that defines the slot and a radially outer surface of the flange portion. Is provided.
By configuring in this way, the winding area can be expanded by the amount of the cutout without affecting the magnetic path of the teeth portion, and the space factor can be increased by increasing the winding amount. As a result, the motor performance can be improved.

In the invention described in claim 2, a start line which is a winding start end of the winding is formed as the notch at a position closest to a root of the teeth portion on a radially inner side surface of the split core body. The stator core according to claim 1, further comprising a groove for receiving the stator core.
By configuring in this way, the starting line can be escaped to the groove formed on the radially inner side surface of the split core body, and the leading line drawing part prevents it from becoming a dead space when winding. Can do. Therefore, the amount of winding can be increased by the amount of dead space, which can contribute to the improvement of motor performance.

The invention described in claim 3 is characterized in that a recess for accommodating a winding at a radially outer end of the windings is provided as the notch on the radially inner side surface of the split core body. To do.
With this configuration, the winding at the radially outer end of the stator core can be wound with the position shifted radially outward by the amount accommodated in the recess. Therefore, the amount of winding of the layer corresponding to the recess can be increased by at least one turn, and the motor performance can be improved by that amount.

The invention described in claim 4 is characterized in that a recess for receiving a winding at a radially inner end of the winding is provided as the notch on the radially outer surface of the flange portion. The stator core according to claim 1.
With this configuration, the winding at the radially inner end of the stator core can be wound with the position shifted radially inward by the amount accommodated in the recess. Therefore, the amount of winding of the layer corresponding to the recess can be increased by at least one turn, and the motor performance can be improved by that amount.

  According to the first aspect of the present invention, the winding is accommodated in at least one of the radially inner side surface formed by the flat surface of the split core body that defines the slot and the radially outer surface of the flange portion. Since the notch that expands the area is provided, the winding area can be expanded by the amount of the notch without affecting the magnetic path of the teeth part, and the space factor can be increased by increasing the amount of winding. As a result, the motor performance can be improved. For example, when the diameter of the winding is large (for example, when the diameter is about 2 mm), the overlapping position of the circular cross-section winding is large in the radial direction of the stator core between adjacent winding layers (about half of the winding diameter). However, by accommodating the winding in the notch, the overlapping position can be shifted in the radial direction of the stator core by one pitch corresponding to the diameter of the winding. You can increase the number of times.

  According to the second aspect of the present invention, a starting line that is a winding start end of the winding is accommodated as the notch at a position closest to the root of the teeth portion on the radially inner side surface of the split core body. Since the starting line is provided, the starting line can be escaped to the groove formed on the inner surface in the radial direction of the split core body, and it is possible to prevent a dead space from being generated at the time of winding because the leading part of the starting line gets in the way. it can. Therefore, the amount of winding can be increased by the amount of dead space, which can contribute to the improvement of motor performance.

  According to the third aspect of the present invention, since the concave portion for accommodating the winding at the radially outer end of the winding is provided on the radially inner side surface of the split core body, the winding at the radially outer end of the stator core is provided. The wire can be wound with the position shifted outward in the radial direction by the amount accommodated in the recess. Therefore, the amount of winding of the layer corresponding to the recess can be increased by at least one turn, and the motor performance can be improved by that amount. For example, when the concave portion is formed corresponding to the position of the winding of the second layer, when there is no concave portion, the position of the winding at the radially outer end of the winding of the second layer is more than the winding position of the starting wire. Although it has become the radially inner side of the stator core, the winding of the radially outer end of the second layer winding is accommodated in the recess, so that the position of the winding of the radially outer end is set to the start line. It can be shifted radially outward from the winding position. Therefore, the winding amount of the second layer can be increased by at least one turn, and the motor performance can be improved by that amount.

  According to the invention described in claim 4, since the concave portion for accommodating the winding at the radially inner end of the winding is provided on the radially outer surface of the flange portion, the winding at the radially inner end of the stator core is provided. Can be wound with the position shifted inward in the radial direction by the amount accommodated in the recess. Therefore, the amount of winding of the layer corresponding to the recess can be increased by at least one turn, and the motor performance can be improved by that amount. For example, when the recess is formed corresponding to the position of the first layer winding, the winding at the radially inner end of the first layer winding is accommodated in the recess, so that the amount of the first layer winding is reduced. It can be increased by at least one turn, which can contribute to the improvement of motor performance.

It is sectional drawing which cut along the axial direction the IPM motor incorporating the stator core in embodiment of this invention. It is sectional drawing seen from the motor shaft direction which shows the state before the assembly of the stator core in embodiment of this invention. It is the figure seen from the motor shaft direction which shows the assembly state of the stator core in embodiment of this invention. The division | segmentation core in embodiment of this invention is shown, (a) is sectional drawing seen from the motor shaft direction, (b) is a principal part enlarged view. It is a perspective view which shows the structure of the split core in embodiment of this invention. It is a perspective view which shows the process of the start line in the split core which comprises the stator core in embodiment of this invention. It is a perspective view which shows the process of the starting line in the split core of the comparative example with respect to embodiment of this invention. It is sectional drawing which showed the structure of the split core which comprises the stator core in another embodiment of this invention, and was seen from the motor axial direction. It is sectional drawing which looked at the structure of the split core shown as a modification of FIG. 8 from the motor axial direction. It is sectional drawing which looked at the structure of one division | segmentation core in an example of the conventional division | segmentation core type stator core from the motor axial direction.

(IPM motor)
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a cross-sectional view of an IPM motor incorporating the stator core of the embodiment cut along the axial direction, FIG. 2 is a cross-sectional view seen from the motor axial direction showing the state before the stator core is assembled, It is the figure seen from the motor shaft direction shown.

  The motor 1 is an IPM motor (embedded magnet synchronous motor) used as a motor for a motorcycle, and includes a first housing 2 attached to a vehicle body BD and a second housing 3 combined with the first housing 2. And have. The outside of the second housing 3 is covered with a cover 15.

(Stator)
The interiors of the first housing 2 and the second housing 3 are sealed spaces, in which the rotor 10, the stator core 21, the bus bar unit 8, and the like are accommodated. The second housing 3 functions as a stator housing, and an annular stator core 21 is fixed to the inner periphery thereof. A coil (also referred to as a winding) 23 is mounted on the stator core 21 via an insulator 22, and the stator 20 is configured by fixing the stator core 21 to the stator housing (second housing 3). .

(Rotor)
In the rotor 10, a magnet holder (reference numeral omitted) on which a permanent magnet is mounted is integrally coupled to a rotating shaft 6 that is rotatably supported at both ends by bearings 4 and 5 on the first housing 2 and the second housing 3. The tip of the rotating shaft 6 protrudes from the central through hole of the first housing 2 via the seal 7, and the tip of the rotating shaft 6 is connected to the driven system of the vehicle.

(Bus bar unit)
The bus bar unit 8 has a plurality of bus bars 9 embedded in a resin molded member (reference number omitted). The bus bar 9 has one end of the coil 23 connected to one end of the bus bar 9, and the other end of the bus bar 9 is a terminal of an external connector. As protruding from the resin mold member.

(Stator core)
As shown in FIGS. 2 and 3, the stator core 21 of the present embodiment is of a split core type that can be split in the circumferential direction. FIG. 4 is a cross-sectional view of one divided core 21A constituting the stator core 21 as viewed from the motor axial direction. The split core 21A is configured by laminating a plurality of plate materials made of a magnetic material in the axial direction of the stator core 21.

(Split core)
A stator core 21 (see FIGS. 2 and 3) constituted by the split core 21A shown in FIG. 4 includes an annular core body 21B fixed to the inner periphery of the stator housing (second housing 3), and a circumferential direction. A plurality of teeth portions 21a that are arranged at equal intervals and extend radially inward from the core main body 21B, and flange portions 21c that are formed to extend to both ends in the circumferential direction at the radially inner tip of each tooth portion 21a. And is equally divided into a plurality in the circumferential direction so as to have one tooth portion 21a.

  Each divided core 21A is provided with a divided core main body 21b, a teeth portion 21a, and a flange portion 21c that are connected in an annular shape to constitute the core main body 21B. Moreover, the teeth part 21a is covered with the insulator 22, The division | segmentation core unit 25 is comprised by winding the coil | winding 23 from it. The coil | winding 23 is accommodated in the slot 21s, and the slot 21s is defined by the division | segmentation core main body 21b, the teeth part 21a, and the collar part 21c. The core body 21B is a portion that forms an annular magnetic path of the stator core 21, and the minimum radial thickness is set so that L / 2 can be secured when L is the width of the tooth portion 21a. Has been.

  In this case, the radially outer side surface 21f of the split core body 21b is configured as an arc surface in accordance with the inner peripheral surface of the stator housing (second housing 3), and the radially inner side surface 21g of the split core body 21b In order to allow the winding to be performed without complicated movement of the machine, it is configured by a flat surface orthogonal to the center line S in the width direction of the tooth portion 21a. Further, at both ends in the circumferential direction of the split core main body 21b, a convex connecting portion 21d and a concave connecting portion 21e are respectively provided, and the convex connecting portion 21d of the split core main body 21b adjacent in the circumferential direction and the concave shape are provided. By fitting the connecting portion 21e, the split core main body 21b is connected in an annular shape to form an annular core main body 21B.

  Further, the radially inner side surface 21h of the flange portion 21c is formed in a circular arc shape corresponding to the outer diameter of the rotor, and the radially outer surface 21i facing the slot 21s goes away from the teeth portion 21a in the circumferential direction. It is formed in the inclined surface inclined toward the inner side in the radial direction. Thus, the slot 21s is configured such that the opening width gradually increases from the slot bottom toward the slot opening.

(Groove of split core)
Further, of the radially inner side surface 21g configured by the flat surface of the split core main body 21b defining the slot 21s, the position closest to the root of the tooth portion 21a is the winding start end of the winding 23. A groove (notch) 21j for accommodating the start line 23a is provided. The groove 21j is formed over the entire axial dimension H of the split core 21A as shown in FIG. 5A because the split core 21A is formed by stacking thin plates.

(Insulator)
The insulator 22 is provided so as to be able to insulate between the winding 23 and the split core 21A when the winding 23 is wound around the tooth portion 21a, and a portion 22a covering the tooth portion 21a and the split core main body A portion 22b covering the radially inner side surface 21g of 21b and a portion 22c covering the radially outer side surface 21i of the flange portion 21c are provided. The insulator 22 also includes a groove-like portion 22j that covers the inner surface of the groove 21j of the radially inner side surface 21g of the split core body 21b.

(Function and effect)
Next, functions and effects will be described.
When winding the coil | winding 23 around the teeth part 21a, as shown in FIG.4 and FIG.6, it winds in the state which accommodated the start line 23a in the groove | channel 21j. The lead-out portion (terminal portion for power input / output) of the start line 23a is drawn out in the axial direction of the stator core 21, and thus the start line 23a is released to the groove 21j formed on the radially inner side surface 21g of the split core body 21b. Thus, as in the comparative example shown in FIG. 7, it is possible to prevent a dead space D from being generated at the time of winding due to the leading portion of the start line 23 a becoming an obstacle. Therefore, the amount of winding can be increased by the amount of dead space. In other words, by accommodating the starting wire 23a in the groove 21j, the winding area can be expanded, and the space factor can be increased by increasing the amount of winding, and as a result, the motor performance is improved. Can do.

(Other embodiments)
In the above-described embodiment, the case where the groove 21j for escaping the starting line 23a is provided at a position closest to the root of the tooth portion 21a of the radially inner side surface 21g of the split core body 21b is shown. The housing area of the winding can also be widened by providing a cutout in at least one of the radially inner side surface 21g of the split core body 21b and the radially outer side surface 21i of the flange portion 21c.

  FIG. 8 shows, as such a notch, a recess 21k that accommodates the winding at the radially outer end of the winding 23 in the radially inner side surface 21g of the split core body 21b and the radial direction of the flange portion 21c. The split core 121A which comprises the stator core of other embodiment which provided the recessed part 21m which accommodates the coil | winding of the radial direction inner end of the coil | windings 23 in the outer surface 21i is shown.

  In this case, the concave portion 21k of the radially inner side surface 21g of the split core main body 21b is arranged corresponding to the position of the winding 23 of the second layer and is recessed from the position 21u of the original shape (flat surface shape). It is formed into a shape. Further, the concave portion 21m of the radially outer surface 21i of the flange portion 21c is arranged corresponding to the position of the winding 23 of the first layer, and the position 21t of the inclined surface which is the original shape is notched, The split core body 21b is formed in a surface shape substantially parallel to the radially inner side surface 21g.

  When comprised in this way, without affecting the magnetic path of the teeth part 21a, the coil | winding area | region can be expanded only by the part which provided the recessed parts 21k and 21m (notch), and the amount of windings can be increased and a space factor can be increased. As a result, the motor performance can be improved.

  That is, when there is no recess 21k, as shown in FIG. 10, the position of the winding 23k at the radially outer end of the second layer winding 23 is larger than the winding position of the start line 23a in the radial direction of the stator core 21. Although the innermost winding 23b of the second layer winding 23b is accommodated in the recess 21k, the position of the outermost winding 23b is set to the start line 23a. Can be shifted radially outward from the winding position. Therefore, the winding amount of the second layer can be increased by at least one turn, which can contribute to the improvement of motor performance.

  Further, by providing a recess 21m for accommodating the winding 23c at the radially inner end of the first layer winding 23 on the radially outer surface 21i of the flange portion 21c, the winding at the radially inner end of the stator core is provided. The wire 23c can be wound with the position shifted radially inward by the amount accommodated in the recess 21m. Therefore, the winding amount of the first layer can be increased by at least one turn, and the motor performance can be improved by that amount.

  In addition, like the split core 221A of the modified example shown in FIG. 9, a curved concave portion 21n (notch) is provided on the radially outer surface 21i of the flange portion 21c, and the first layer of the winding 23 is formed in the concave portion 21n. You may make it accommodate the coil | winding 23c of the radial direction inner end of them. By comprising in this way, in addition to the effect similar to the above-mentioned embodiment, a space factor can be improved further.

  Moreover, the accommodation area | region of the coil | winding 23 is extended to arbitrary positions of the radial direction inner side surface 21g comprised by the flat surface of the split core main body 21b which defines the slot 21s, and the radial direction outer side surface 21i of the collar part 21c. Notches (grooves and recesses) may be provided.

21 Stator Core 21A, 121A, 221A Split Core 21B Core Main Body 21a Teeth Part 21b Split Core Main Body 21c Gutter 21g Radial Inner Side 21i of Split Core Main Body 21i Radial Outer Side 21j Groove (Notch)
21k recess (notch)
21m recess (notch)
21n recess (notch)
22 Insulator 23 Winding (coil)
23a Starting line

Claims (4)

An annular core body, a plurality of teeth portions arranged at equal intervals in the circumferential direction and extending radially inwardly from the core body, and on both ends in the circumferential direction at the distal ends on the radially inner sides of the respective tooth portions The core body by being connected in an annular shape to each of the divided cores that are divided into a plurality of circumferential directions so as to have one tooth portion each. A slot that accommodates a winding wound around the teeth portion via an insulator, the divided core main body and the tooth portion. In the stator core that is defined by the flange portion, and the radially inner side surface of the divided core body is configured by a flat surface orthogonal to the center line of the teeth portion,
At least one of a radially inner side surface formed by a flat surface of the split core body defining the slot and a radially outer surface of the flange portion is provided with a notch for expanding the accommodation area of the winding. A stator core characterized by that.   Of the radially inner side surface of the split core body, a groove that accommodates a starting line that is a winding start end of the winding is provided as the notch at a position closest to the root of the teeth portion. The stator core according to claim 1.   The recessed part which accommodates the coil | winding of the radial direction outer end of the said winding as said notch is provided in the radial direction inner surface of the said split core main body as described in Claim 1 or 2 characterized by the above-mentioned. Stator core.   The concave part which accommodates the coil | winding of the radial direction inner end of the said coil | windings as the said notch is provided in the radial direction outer surface of the said collar part, The any one of Claims 1-3 characterized by the above-mentioned. The stator core according to item.

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