JP2018085853A - Stator core - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a stator core capable of restraining the torque reduction of a motor caused by a swaged portion.SOLUTION: A stator core 100 for a motor 200 laminated with a plurality of electrical steel sheets 1 comprises: an annular back yoke 2; a plurality of teeth 3 extending in the radial direction from the annular back yoke 2 towards a rotor 201 of the motor 200; and a swaged portion 5 for fixing the plurality of the electrical steel sheets 1 to each other. The swaged portion 5 is arranged in the middle of the stator core 100 of the teeth 3 in the circumferential direction and in the vicinity of the root of the teeth 3.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a stator core.

  Conventionally, a stator core having a caulking portion is known (see, for example, Patent Document 1).

  The laminated iron core (stator core) described in Patent Document 1 is configured such that a plurality of iron core pieces (electromagnetic steel plates) are laminated. The laminated core includes an annular back yoke portion. The laminated core includes a caulking portion that is caulked in the laminating direction. The caulking portion is provided in the vicinity of the center of the back yoke portion in the radial direction of the laminated core. Near the center of the back yoke portion, the density of magnetic flux (the amount of magnetic flux that passes) is relatively large.

JP 2013-135543 A

  However, in the laminated iron core (stator core) of Patent Document 1, a caulking portion is provided in the vicinity of the center of the back yoke portion where the density of magnetic flux (the amount of magnetic flux that passes) is relatively large. There is an inconvenience that the ratio of increases. For this reason, there exists a problem that the torque of a motor reduces.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a stator core capable of suppressing a reduction in motor torque due to a caulking portion. .

  A stator core according to an aspect of the present invention is a stator core for a rotating electrical machine in which a plurality of electromagnetic steel plates are laminated, and includes a plurality of annular back yokes and a plurality of radial back yokes extending radially from the annular back yoke toward the rotor of the rotating electrical machine. And a caulking portion for fixing a plurality of electromagnetic steel plates, and the caulking portion is disposed in the center in the circumferential direction of the stator core of the tooth and in the vicinity of the root of the tooth.

  Here, in general, the magnetic flux branches to both sides (left and right as viewed from the radial direction) at the center in the circumferential direction of the stator core of the tooth and in the vicinity of the root of the tooth, and flows from the tooth side to the back yoke side. Focusing on this point, in the stator core according to one aspect of the present invention, as described above, the caulking portion is arranged at the center in the circumferential direction of the stator core of the tooth and in the vicinity of the root of the tooth, so that the caulking portion is magnetic flux. Since the magnetic flux is arranged in the vicinity of the portion where the magnetic flux is branched (the portion where the magnetic flux is branched and the magnetic flux does not pass or the amount of passage is small), it is possible to suppress the passage of the magnetic flux from being blocked by the caulking portion. As a result, it is possible to suppress a reduction in motor torque due to the caulking portion.

  According to the present invention, as described above, it is possible to provide a stator core capable of suppressing a reduction in motor torque due to a caulking portion.

It is a top view of the stator core by one Embodiment of this invention. It is an enlarged plan view of a stator core according to an embodiment of the present invention. It is a top view for demonstrating the flow of the magnetic flux of the stator core by one Embodiment of this invention. It is sectional drawing along the 300-300 line of FIG. It is an enlarged plan view of a stator core according to a comparative example. It is an enlarged plan view of the stator core by the modification of one Embodiment of this invention.

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

[This embodiment]
With reference to FIGS. 1-6, the structure of the stator core 100 by this embodiment is demonstrated. In the present specification, the “rotating axis direction” means the rotating axis direction (Z direction) of the stator core 100. Further, the “circumferential direction” means a circumferential direction (X1 direction or X2 direction, see FIG. 1) of the stator core 100 in a state completed as the stator core 100. Further, “inward in the radial direction” means a direction (Y1 direction, see FIG. 1) toward the center O (see FIG. 1) of the stator core 100 in a state completed as the stator core 100. The “radially outer side” means a direction (Y2 direction, see FIG. 1) toward the outside of the stator core 100 in a state completed as the stator core 100.

  As shown in FIG. 1, the stator core 100 is provided in the motor 200. Moreover, in the stator core 100, the some electromagnetic steel plate 1 is laminated | stacked on the rotating shaft direction (refer FIG. 4). In addition, a rotor 201 is disposed in the motor 200 on the radially inner side of the stator core 100. Note that the rotation center of the rotor 201 is the same as the center O of the stator core 100. The motor 200 is an example of the “rotary electric machine” in the claims.

  In addition, the stator core 100 is provided with an attachment hole 101 for attaching the stator core 100 to a housing or the like (not shown) with a bolt or the like. A plurality (four in this embodiment) of mounting holes 101 are provided. The plurality of mounting hole portions 101 are provided at equiangular intervals (90-degree intervals in the present embodiment).

  The stator core 100 includes an annular back yoke 2. The stator core 100 includes a plurality (24 in the present embodiment) of teeth 3 extending radially inward from the annular back yoke 2.

  Here, in this embodiment, as shown in FIG. 2, the width W <b> 1 of the back yoke 2 in the radial direction of the stator core 100 is smaller than the width W <b> 2 of the teeth 3 in the circumferential direction of the stator core 100. Specifically, the maximum value of the width W1 of the back yoke 2 is smaller than the width W2 of the teeth 3. Note that the width W1 of the back yoke 2 is the smallest at the approximate center of the two adjacent teeth 3 (substantially the center in the circumferential direction of a slot 4 described later). Further, the width W2 of the tooth 3 is substantially constant in the radial direction. In FIG. 2, the motor 200 and the rotor 201 are not shown for the sake of simplicity.

  As shown in FIGS. 1 and 2, in the stator core 100, a slot 4 is provided between two adjacent teeth 3. The slot 4 is provided with an inner end face 4a on the outer side in the radial direction. The inner end surface 4 a is formed so as to be recessed outward in the radial direction at the approximate center in the circumferential direction of the slot 4.

  The stator core 100 includes a caulking portion 5 for fixing the plurality of electromagnetic steel plates 1.

  Here, in the present embodiment, the caulking portion 5 is disposed at the center in the circumferential direction of the tooth 3 and in the vicinity of the root of the tooth 3. Here, the vicinity of the root of the tooth 3 refers to a connection point A (see FIG. 2) between the radially outer inner end surface 4 a of the adjacent slots 4 in the slots 4 and the teeth 3 (included in the common teeth 3). It means the vicinity of the line segment α (see FIG. 2) connecting the connection points A).

  In the present embodiment, as shown in FIG. 1, a plurality of caulking portions 5 are provided. The plurality of caulking portions 5 are disposed in the vicinity of the root of the tooth 3 at equal angular intervals. Specifically, eight caulking portions 5 are provided at intervals of 45 degrees.

  In the present embodiment, as shown in FIG. 2, the caulking portion 5 is provided so as to extend along the radial direction of the stator core 100 when viewed from the rotation axis direction. Specifically, the caulking portion 5 has a rectangular shape extending along the radial direction of the stator core 100 when viewed from the rotation axis direction. Specifically, the width of the short side of the rectangular caulking portion 5 is W3. Moreover, the width | variety of the long side of the crimping | crimped part 5 is W4 larger than W3.

  In the present embodiment, the maximum value of the width W3 of the caulking portion 5 in the circumferential direction of the stator core 100 is ¼ or less of the width W2 of the teeth 3. Specifically, the maximum value of the width W3 of the caulking portion 5 is about 1/6 of the width W2 of the tooth 3 in the circumferential direction of the stator core 100. In the present embodiment, the width W3 of the caulking portion 5 is substantially constant in the radial direction.

  Further, in the present embodiment, the caulking portion 5 is disposed so as to straddle both the teeth 3 and the back yoke 2. That is, the caulking portion 5 is disposed so as to cross the line segment α as viewed from the rotation axis direction.

  In the present embodiment, the length L1 between the radially outer end 5a of the caulking portion 5 and the root of the tooth 3 is equal to the radial inner end 5b of the caulking portion 5 and the root of the tooth 3. It is smaller than the length L2. That is, the length L2 between the radially inner end portion 5b of the caulking portion 5 and the line segment α is larger than the length L1 between the radially outer end portion 5a of the caulked portion 5 and the line segment α. large. The end 5a and the end 5b are examples of the “end opposite to the rotor side” and the “end on the rotor side”, respectively, in the claims.

  In the present embodiment, the radially outer end 5a of the caulking portion 5 is disposed radially inward from the center X of the back yoke 2 in the radial direction. That is, the length L3 between the radially outer end 5a of the caulking portion 5 and the outer peripheral edge of the stator core 100 is the length between the radially outer end 5a of the caulking portion 5 and the line segment α. Larger than L1.

  As shown in FIG. 3, the magnetic flux flowing from the tooth 3 branches to the X1 direction side and the X2 direction side at the center in the circumferential direction of the tooth 3 and in the vicinity of the root of the tooth 3. Further, the end portion 5b on the radially inner side of the caulking portion 5 is disposed on the Y2 direction side with respect to the portion where the magnetic flux branches. That is, the magnetic flux flows from the tooth 3 side to the back yoke 2 side so as to avoid the caulking portion 5. In FIG. 3, the flow of magnetic flux is indicated by a dotted line. In FIG. 3, the motor 200 and the rotor 201 are not shown for simplicity.

  As shown in FIG. 4, the electromagnetic steel plate 1 is provided with a caulking convex portion 1a. The surface (back surface) of the caulking projection 1a is formed so as to protrude upward (Z1 direction side). Further, the lower side (Z2 direction side) of the caulking convex portion 1a is formed in a concave shape. The convex portion of the caulking convex portion 1a is press-fitted (fitted) into the concave portion of the caulking convex portion 1a. The uppermost electromagnetic steel plate 1 is not provided with the caulking convex portion 1a, but is provided with the caulking hole portion 1b for allowing the caulking convex portion 1a of the lower electromagnetic steel plate 1 to pass therethrough. That is, the caulking portion 5 includes a plurality of caulking convex portions 1a and caulking hole portions 1b. The plurality of electromagnetic steel sheets 1 are fixed (temporarily fixed) by the plurality of caulking convex portions 1a and the caulking hole portions 1b, so that handling during manufacture of the stator core 100 can be facilitated.

(simulation)
Next, with reference to FIG. 2 and FIG. 5, the simulation result at the time of driving the motor 200 (refer FIG. 1) with the stator core 100 of this embodiment is demonstrated.

  When the caulking portion 5 is provided at the base of the tooth 3 (see FIG. 2), the torque reduction amount of the motor 200 is approximately the center of the back yoke 2 between the two adjacent teeth 3 by the caulking portion 5. It was confirmed that the torque was reduced to 1/3 or less of the torque reduction amount (see FIG. 5). Note that the reduction amount of the torque of the motor 200 means a reduction amount with respect to the case where the caulking portion 5 is not provided in the stator core 100. Further, the above simulation comparison is a comparison in the case where the number of caulking portions 5 provided in the stator core 100 is the same. In FIG. 5, the motor 200 and the rotor 201 are not shown for simplicity.

(Effect of this embodiment)
In the above embodiment, the following effects can be obtained.

  The stator core (100) of the above embodiment is a stator core (100) for a rotating electrical machine (200) in which a plurality of electromagnetic steel plates (1) are laminated, and includes an annular back yoke (2) and an annular back yoke ( 2) A plurality of teeth (3) extending in the radial direction from the rotating electric machine (200) toward the rotor (201), and a caulking portion (5) for fixing the plurality of electromagnetic steel sheets (1) to each other. . And the crimping | crimped part (5) is arrange | positioned in the center of the circumferential direction of the stator core (100) of teeth (3), and the base vicinity of teeth (3). Here, in general, the magnetic flux branches to both sides (left and right as viewed from the radial direction) at the center in the circumferential direction of the stator core (100) of the tooth (3) and in the vicinity of the root of the tooth (3). 3) Flows from the side to the back yoke (2) side. By paying attention to this point, the caulking portion (5) is disposed at the center in the circumferential direction of the stator core (100) of the teeth (3) and in the vicinity of the root of the teeth (3), so that the caulking portion (5) has a magnetic flux. Since it is arranged in the vicinity of the branching point (portion where the magnetic flux does not pass or the amount of passage is small), it is possible to suppress the passage of the magnetic flux from being blocked by the caulking portion (5). As a result, a reduction in torque of the motor (200) due to the caulking portion (5) can be suppressed.

  Moreover, in the stator core (100) of the said embodiment, the crimping | crimped part (5) is provided so that it may extend along the radial direction of a stator core (100). With this configuration, the direction in which the caulking portion (5) extends and the direction in which the teeth (3) extend (direction in which the magnetic flux flows) can be made the same, so the direction in which the caulking portion (5) extends and the teeth ( Compared with the case where the direction in which 3) extends intersects with the caulking portion (5), it is possible to suppress the passage of magnetic flux in the teeth (3). Moreover, sufficient caulking strength can be ensured by the portion of the caulking portion 5 extending in the same direction as the direction in which the teeth 3 extend while suppressing the passage of magnetic flux.

  Moreover, in the stator core (100) of the said embodiment, a crimping | crimped part (5) has a rectangular shape extended along the radial direction of a stator core (100). If comprised in this way, the magnitude | size of the crimping part (5) in the circumferential direction of a stator core (100) can be made small compared with the magnitude | size of the crimping part (5) in the radial direction of a stator core (100). That is, since the size of the caulking portion (5) in the direction orthogonal to the direction in which the magnetic flux flows can be made relatively small, the passage of the magnetic flux in the teeth (3) is inhibited by the caulking portion (5). Can be easily suppressed.

  Moreover, in the stator core (100) of the said embodiment, the crimping | crimped part (5) is arrange | positioned so that it may straddle both the teeth (3) and the back yoke (2). If comprised in this way, compared with the case where the caulking part (5) is arrange | positioned only at the teeth (3), the caulking part (5) can be arrange | positioned on the opposite side to the rotor (201) side. Thereby, a crimping | crimped part (5) can be easily arrange | positioned on the opposite side to the rotor (201) side rather than the location where the magnetic flux branches. As a result, it is possible to further suppress the passage of magnetic flux from being blocked by the caulking portion (5).

  Moreover, in the stator core (100) of the said embodiment, the length (L1) between the edge part (5a) on the opposite side to the rotor (201) side of a crimping | crimped part (5) and the root of a teeth (3) is The length (L2) between the end (5b) of the caulking portion (5) on the rotor (201) side and the root of the teeth (3) is smaller. Here, the position where the caulking portion (5) is disposed is the periphery of the back yoke (2) (the outer periphery when the rotor (201) is disposed radially inside, and the rotor (201) is disposed radially outside). The mechanical strength of the stator core (100) (back yoke (2)) decreases as the distance from the inner peripheral edge approaches. Therefore, the length (L1) between the end (5a) of the caulking part (5) opposite to the rotor (201) and the root of the teeth (3) is set to the rotor (201) of the caulking part (5). ) Side end portion (5b) and the base of teeth (3) are made smaller than the length (L2), so that caulking portion (5) can be easily moved away from the periphery of back yoke (2). it can. Thereby, the fall of the mechanical strength of a stator core (100) (back yoke (2)) can be suppressed.

  In the stator core (100) of the above embodiment, the maximum value of the width (W3) of the caulking portion (5) in the circumferential direction of the stator core (100) is ¼ or less of the width (W2) of the tooth (3). It is. If comprised in this way, the width | variety of the path | route through which the magnetic flux in the teeth (3) flows can be made comparatively large with respect to the width | variety (W3) of a crimping | crimped part (5) in the circumferential direction of a stator core (100).

  Moreover, in the stator core (100) of the said embodiment, the edge part (5a) on the opposite side to the rotor (201) side of a crimping | crimped part (5) is rather than center (X) of the back yoke (2) in radial direction. , Arranged on the rotor (201) side. If comprised in this way, the edge part (5a) on the opposite side to the rotor (201) side of the crimping | crimped part (5) will be arrange | positioned the periphery (rotor (201) of the back yoke (2) inside radial direction. In this case, it can be easily moved away from the outer peripheral edge, or the inner peripheral edge when the rotor (201) is arranged radially outside. Thereby, the fall of the mechanical strength of a stator core (100) (back yoke (2)) can further be suppressed.

  In the stator core (100) of the above embodiment, the width (W1) of the back yoke (2) in the radial direction of the stator core (100) is greater than the width (W2) of the teeth (3) in the circumferential direction of the stator core (100). Is also small. If comprised in this way, the magnitude | size (diameter) of the radial direction of a stator core (100) can be made small by reducing the width | variety (W1) of a back yoke (2).

  Further, when the width (W1) of the back yoke (2) is reduced, the ratio of the width (W3) of the caulking portion (5) to the width (W1) of the back yoke (2) is increased. As a result, when the caulking portion (5) is disposed on the back yoke (2), there is a disadvantage that the proportion of magnetic flux that is blocked by the caulking portion (5) increases. Therefore, the thickness of the back yoke (2) is reduced by arranging the caulking portion (5) in the vicinity of the root of the teeth (3) having a width (W2) larger than the width (W1) of the back yoke (2). However, it is possible to effectively suppress the passage of the magnetic flux by the caulking portion 5.

  In the stator core (100) of the above embodiment, a plurality of caulking portions (5) are provided, and the plurality of caulking portions (5) are arranged near the root of the tooth (3) at equal angular intervals. If comprised in this way, a some electromagnetic steel plate (1) can be equally fixed to the circumferential direction by the crimping | crimped part (5). Further, the caulking portion (5) is disposed on the relatively peripheral side in the radial direction of the stator core (100) (the outer peripheral side when the rotor (201) is disposed on the radially inner side, and the rotor (201) is disposed on the radially outer side. Since it is arrange | positioned in the base vicinity of the tooth | gear (3) of the inner periphery in the case where it is carried out, a some electromagnetic steel plate (1) can be fixed comparatively stably.

[Modification]
The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description of the embodiment but by the scope of claims for patent, and further includes all modifications (modifications) within the meaning and scope equivalent to the scope of claims for patent.

  For example, in the above embodiment, the caulking portion 5 has an example of a rectangular shape, but the present invention is not limited to this. For example, as shown in FIG. 6, the caulking portion 5 may have a circular shape. In this case, it is preferable that the caulking portion 5 is arranged so that the radially inner end portion 5b of the caulking portion 5 is in contact with the line segment α. Further, the caulking portion 5 may have a shape other than a rectangular shape or a circular shape (for example, a triangular shape). In FIG. 6, the motor 200 and the rotor 201 are not shown for simplicity.

  Moreover, in the said embodiment, although the electromagnetic steel plate 1 showed the example by which the crimping convex part 1a which protrudes upwards (Z1 direction side) was provided, this invention is not limited to this. For example, the caulking convex portion 1a may protrude downward (Z2 direction side).

  Moreover, in the said embodiment, although the example where the caulking part 5 was provided eight was shown, this invention is not limited to this. For example, 8 or more (for example, 12 or 24) caulking portions 5 may be provided. Further, it may be 8 or less (for example, 4 or 6).

  Moreover, in the said embodiment, although the width W2 of the teeth 3 showed the example substantially constant in radial direction, this invention is not limited to this. For example, the radially inner width (circumferential width) of the teeth 3 may be larger than the radially outer width (circumferential width). Also, the radially inner width (circumferential width) may be smaller than the radially outer width (circumferential width).

  In the above embodiment, the example in which the width W1 of the back yoke 2 is the smallest at the approximate center between the two adjacent slots 4 has been described, but the present invention is not limited to this. For example, the width W1 of the back yoke 2 may be substantially constant.

  Moreover, although the maximum value of the width W3 of the caulking portion 5 is about 1/6 of the width W2 of the tooth 3 in the circumferential direction in the above embodiment, the present invention is not limited to this. As long as the maximum value of the width W3 of the caulking portion 5 is 1/4 or less of the width W2 of the tooth 3, it may be other than 1/6 (for example, 1/8).

  Moreover, in the said embodiment, although the example which the crimping part 5 straddled both the back yoke 2 and the teeth 3 was shown, this invention is not limited to this. For example, the caulking portion 5 may be provided only on the teeth 3.

  Moreover, in the said embodiment, although the rotor 201 showed the example arrange | positioned at the radial inside of the stator core 100, this invention is not limited to this. For example, the rotor 201 may be disposed on the radially outer side of the stator core 100.

DESCRIPTION OF SYMBOLS 1 Magnetic steel plate 2 Back yoke 3 Teeth 5 Caulking part 5a End part (End part on the opposite side to a rotor side)
5b End (end on the rotor side)
100 Stator core 200 Motor (rotary electric machine)
201 Rotor L1 length (length between the end of the caulking portion opposite to the rotor side and the root of the tooth)
L2 length (the length between the end of the caulking portion on the rotor side and the root of the teeth)
W1 width (back yoke width)
W2 width (teeth width)
W3 width (caulking width)
X center (center of back yoke)

Claims (9)

A stator core for a rotating electrical machine in which a plurality of electromagnetic steel sheets are laminated,
An annular back yoke,
A plurality of teeth extending in a radial direction from the annular back yoke toward the rotor of the rotating electrical machine;
A caulking portion for fixing the plurality of electromagnetic steel sheets,
The said caulking part is a stator core arrange | positioned in the center of the circumferential direction of the said stator core of the said teeth, and the base vicinity of the said teeth.   The stator core according to claim 1, wherein the caulking portion is provided so as to extend along a radial direction of the stator core.   The stator core according to claim 2, wherein the caulking portion has a rectangular shape extending along a radial direction of the stator core.   The stator core according to claim 2, wherein the caulking portion is disposed so as to straddle both the teeth and the back yoke.   The length between the end of the caulking portion opposite to the rotor side and the root of the teeth is smaller than the length between the end of the caulking portion on the rotor side and the root of the teeth. The stator core according to claim 4.   The stator core according to any one of claims 2 to 5, wherein in the circumferential direction of the stator core, a maximum value of the caulking portion is ¼ or less of a width of the teeth.   The stator core according to any one of claims 1 to 6, wherein an end portion of the caulking portion opposite to the rotor side is disposed on the rotor side with respect to a center of the back yoke in a radial direction. .   The stator core according to any one of claims 1 to 7, wherein a width of the back yoke in a radial direction of the stator core is smaller than a width of the teeth in a circumferential direction of the stator core.   The stator core according to any one of claims 1 to 8, wherein a plurality of the caulking portions are provided, and the plurality of caulking portions are arranged in the vicinity of a root of the teeth at equal angular intervals.

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