JP2012257417A - Rotor core and method of manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotor core capable of achieving an increase in efficiency of an operation of welding between laminations of core sheets and improving performance of a rotary electric machine, and a method of manufacturing the same.SOLUTION: A rotor core, in which a plurality of core sheets S obtained by forming a magnetic steel sheet in a predetermined shape are stacked in a rotation axis direction, includes a welded part 26 in which the two core sheets S brought into contact with each other are welded to each other by laser welding, and a receding part 27 is provided on either or both of the two core sheets S welded to each other in the welded part 26. The welded part 26 and the receding part 27 provided on either or both of the other core sheets S brought into contact with sheet surfaces of the two core sheets S welded to each other in the welded part 26 are arranged adjacently to each other in the rotation axis direction.

Description

  The present invention relates to a rotor core for a radial gap type rotating electrical machine and a method for manufacturing the same.

  A radial gap type rotating electrical machine is a rotating electrical machine that includes a rotor that is arranged to be rotatable about a rotation axis, and a stator that is arranged with a gap in the radial direction of the rotor. The rotor includes a rotor core formed by laminating a large number of core sheets formed of electromagnetic steel sheets in a predetermined shape in the rotation axis direction. When forming this rotor core, as one of the methods for integrating a large number of laminated core sheets, a method of welding the laminated core sheets adjacent in the rotation axis direction by laser welding is used.

  As one of the welding methods, a technique is known in which the welded portions formed by laser welding are welded between the stacked core sheets so that the welded portions are arranged in a staggered manner with respect to the stacking direction of the core sheets. (For example, refer to Patent Document 1). Such a welding method is described in Patent Document 1 as a welding method for manufacturing a stator core, but can also be used for manufacturing a rotor core. According to this welding method, it is possible to prevent excessive heat input to each core sheet during welding, and to prevent a reduction in dimensional accuracy of the rotor core due to distortion of the core sheet. Moreover, since it can prevent that each core sheet | seat short-circuits linearly in the lamination direction by welding, an eddy current loss can be reduced. Thereby, there exists an advantage that the performance improvement of a rotary electric machine can be aimed at.

  However, when the rotor core is manufactured using the above-described welding method, if the welded portion is formed so as to be shifted in the stacking direction of each core sheet, the performance of the rotating electrical machine may be reduced due to this. is there. For example, when a plurality of core sheets are short-circuited linearly in the stacking direction due to a shift of the welded portion, an increase in eddy current loss is caused. On the other hand, when the core sheet is not welded between layers, the mechanical strength is insufficient and vibration may occur. For this reason, it is necessary to locally and accurately weld between the laminations of the core sheets.

  As described in Patent Document 1, in order to weld locally and accurately between the laminations of the core sheets, accuracy of the sheet thickness level of the core sheets is required. However, the core sheet constituting the rotor core of the rotating electrical machine is generally formed by punching and forming a very thin electromagnetic steel sheet having a thickness of about 0.3 to 0.5 mm. For this reason, it is compelled to perform welding that requires high accuracy perfectly between all the laminations of a large number of core sheets without any reduction in accuracy level. Therefore, such welding work is a very time-consuming work.

Japanese Patent Laid-Open No. 9-219941

  The present invention has been made in view of the above circumstances, and provides a rotor core capable of improving the efficiency of a rotating electrical machine and at the same time realizing the efficiency of welding work between core sheet laminations, and a method for manufacturing the same. The purpose is to do.

  The present invention is a rotor core formed by laminating a plurality of core sheets formed of electromagnetic steel sheets in a predetermined shape in the direction of the rotation axis, formed on the outer periphery or inner periphery of each core sheet, and one of the core sheets, Provided in one or both of a welded portion in which the other core sheet in contact with the sheet surface of the one core sheet is welded to each other by laser welding and two core sheets welded to each other in the welded portion. A retreating part in which a part of the outer periphery or inner periphery of the core sheet is retreated in the sheet surface direction by a distance longer than the penetration depth of the core sheet by laser welding at a position different from the position where the part is formed The welded portion, and the retracted portion provided on one or both of the other core sheets that contact the sheet surfaces of the two core sheets welded to each other at the welded portion, Characterized in that it is disposed adjacent to.

  The rotor core of the present invention includes a laminated surface formed by each outer periphery or inner periphery of the plurality of core sheets, and the welded portion and the retracted portion are adjacent to each other in the circumferential direction on the laminated surface. The two core sheets that are linearly arranged from one end to the other end in the rotation axis direction and are adjacent to each other in the rotation axis direction are either in two or three locations that are adjacent to each other in the circumferential direction on the laminated surface. It is characterized in that they are welded to each other only at the welded portion formed in one place.

  The rotor core of the present invention is arranged so that the retreating portion provided in one core sheet is not adjacent to the retreating portion provided in another core sheet contacting the seat surface of the one core sheet in the rotation axis direction. It is characterized by being.

  In the rotor core of the present invention, the core sheet includes a plurality of magnetic pole portions arranged in the circumferential direction, and the welded portion and the retracted portion are adjacent to the pole center portion or the circumferential direction of the magnetic pole portion of each core sheet. It is characterized by being formed in the inter-electrode portion.

  The rotor core according to the present invention is characterized in that the welded portion and the retracted portion are formed for each pole pair in the magnetic pole portion.

  The present invention also relates to a method for manufacturing a rotor core, in which a plurality of core sheets each having an electromagnetic steel sheet formed in a predetermined shape are laminated in the rotation axis direction, the step of preparing the electromagnetic steel sheet, and punching the electromagnetic steel sheet A peripheral portion including an outer periphery and an inner periphery of the core sheet is formed, and a retracted portion in which a part of the outer periphery or the inner periphery is retreated in the sheet surface direction by a predetermined distance is formed at a predetermined position on the outer periphery or the inner periphery. The core sheet punching step and each core sheet obtained by the punching step are laminated so that one or both of the two core sheets adjacent in the rotation axis direction are the core sheet provided with the receding portion. The stacking step in which the receding portion is disposed at a predetermined position, and the core sheets stacked by the stacking step are arranged on the outer periphery or inner periphery of the two core sheets adjacent in the rotation axis direction. Characterized in that it comprises a welding step of welding position by laser welding adjacent to one or both provided in the retraction portion of the other core sheet in the rotational axis direction in contact with each sheet surface of the core sheet, a.

  The rotor core manufacturing method of the present invention is provided in one or both of the retracted portion provided in one core sheet and the other core sheet adjacent to the one core sheet in the rotation axis direction in the laminating step. The receding portions are arranged at two or three locations adjacent to each other in the circumferential direction, and the receding portions are respectively rotated on the laminated surfaces formed by the outer circumferences or inner circumferences of the laminated core sheets. It is characterized by being arranged in a straight line at regular intervals in the axial direction.

  In the method of manufacturing a rotor core according to the present invention, in the punching step, a movable cutting means that can change a punching position with respect to the electromagnetic steel sheet is used to change the punching position with respect to each core sheet, so that the receding portion is arranged on the outer periphery or inside of each core sheet. It is formed at a predetermined position on the circumference.

  Alternatively, in the method for manufacturing a rotor core according to the present invention, in the laminating step, a core sheet having the same shape punched and formed by the punching step is rotated relative to the already laminated core sheets by a predetermined angle in the circumferential direction. And laminating them.

  According to the rotor core of the present invention, by adopting a core sheet provided with a receding portion on the outer periphery or inner periphery, the efficiency of the welding work between the lamination of the core sheets and the improvement of the performance of the rotating electrical machine are simultaneously performed. It can be realized. That is, the laser beam irradiated at the time of laser welding is not focused at the retracted portion, and therefore the core sheet is not welded even if the laser is irradiated onto the retracted portion. According to the rotor core of the present invention, since the welded portion is formed at a position adjacent to the retreating portion and the rotation axis direction, other core sheets other than the core sheet to be welded are short-circuited linearly in the rotation axis direction. Can be surely prevented. Therefore, it is possible to accurately and reliably weld the core sheets between the stacked layers without requiring high-precision work. Thereby, the labor of welding work can be saved greatly, and eddy current loss resulting from a short circuit can be reduced.

  In the present invention, the welded portion and the receding portion may be arranged linearly from one end to the other end in the rotational axis direction at two or three locations adjacent to each other in the circumferential direction on the lamination surface. Further, the labor of welding work can be further reduced. That is, since laser welding can be performed by linear continuous welding, positioning in the direction of the rotation axis (that is, positioning relative to the stack of core sheets) can be omitted. Even when laser welding is performed by spot welding, the positioning accuracy can be relaxed, so that work efficiency can be improved. Thereby, further efficiency improvement of the welding operation can be achieved.

  In the present invention, if the retreating portion provided in one core sheet is disposed so as not to be adjacent to the retreating portion provided in another core sheet in contact with the sheet surface of the one core sheet in the rotation axis direction. The core sheet to be welded can be limited to two. Thereby, the effect similar to the case where it welds only between the lamination | stacking of a core sheet with high precision can be acquired, without requiring a highly accurate welding operation. Moreover, since the welded portions are formed in a regularly dispersed arrangement between the laminations of the core sheets, the influence of heat during welding can be dispersed. Thereby, distortion due to welding heat hardly occurs, and the dimensional accuracy of the rotor core can be increased.

  In the present invention, if the welding part and the receding part are formed at the pole center part of the magnetic pole part of each core sheet, the distance from the outer periphery of the core sheet to the magnet hole part is long. Can be reduced. At the same time, it is possible to effectively prevent the generation of eddy currents at the pole center having a high magnetic flux density. In addition, if the welded part and the receding part are formed in the inter-polar part of the magnetic pole part adjacent in the circumferential direction, it is possible to perform welding while avoiding a part having a high magnetic flux density. Can be more effectively reduced.

  In the present invention, if the welded portion and the receding portion are formed for each pole pair in the magnetic pole portion, the amount of magnetic flux passing between them is constant, so that the generation of eddy current can be further reduced. Thereby, eddy current loss is further reduced and the performance of the rotating electrical machine can be further improved.

  Moreover, according to the manufacturing method of the rotor core which concerns on this invention, the rotor core which concerns on this invention can be efficiently produced by employ | adopting the preparation process, punching process, lamination | stacking process, and welding process which were mentioned above. That is, since the quality accuracy can be maintained even if the operation accuracy in the welding process is reduced, the efficiency of the welding operation can be realized.

  In the laminating step, if the receding portions are arranged in two or three locations adjacent to each other in the circumferential direction on the laminating surface so as to be linearly arranged with a certain interval in the rotation axis direction, welding work can be performed. Time and effort can be further reduced. That is, since laser welding can be performed by linear continuous welding, positioning in the direction of the rotation axis (that is, positioning relative to the stack of core sheets) can be omitted. In addition, even when laser welding is performed by spot welding, positioning is facilitated because high-precision work is not required as in the past. Thereby, further efficiency improvement of the welding operation can be achieved.

  If a movable cutting means is employed as the means for forming the retracted portion in the punching step, the stacking step can be greatly simplified. That is, according to the movable cutting means, the retreating portion can be formed at a predetermined position on the outer periphery or the inner periphery of each core sheet by changing the punching position for each core sheet. Therefore, if the punching position is set in advance, the receding portion can be stacked in a desired position on the stacking surface by simply stacking the core sheets in the punching order. Thereby, the production efficiency of the rotor core of the present invention can be greatly improved.

  Alternatively, if the laminating process is configured so that the core sheets punched in the same shape are rotated by a predetermined angle in the circumferential direction relative to the already laminated core sheets, the punching process is greatly increased. Can be simplified. That is, in the punching step, it is only necessary to form a core sheet having the same shape, and therefore the steps such as positioning of the mold and selection of the mold can be omitted or simplified. Moreover, since the said recessed part can be stamped and formed in the outer periphery or inner periphery of each core sheet with one metal mold | die, installation cost can be reduced.

It is a top view which shows the rotor core which concerns on 1st embodiment. FIG. 2 is a partial front view showing a laminated surface when a region surrounded by a two-dot chain line in FIG. 1 is viewed in a radial direction. It is a perspective view which shows (a) 1st core sheet, (b) 2nd core sheet, and (c) 3rd core sheet which comprise the split core which concerns on 1st embodiment. It is a perspective view which shows the laminated body which concerns on 1st embodiment. It is (a) rear view and (b) top view which show a part of division | segmentation core which concerns on 1st embodiment. It is a top view which shows the rotor core which concerns on 2nd embodiment. FIG. 7 is a partial front view showing a laminated surface when a region surrounded by a two-dot chain line in FIG. 6 is viewed in a radial direction. It is a perspective view which shows the 4th core sheet | seat which comprises some split cores concerning 2nd embodiment. It is a perspective view which shows the laminated body which concerns on 2nd embodiment. It is (a) rear view and (b) top view which show a part of division | segmentation core which concerns on 2nd embodiment. It is a top view which shows the modification of the rotor core which concerns on 1st embodiment. It is a top view which shows the modification of the rotor core which concerns on 2nd embodiment. It is a top view which shows the other modification of the rotor core which concerns on 1st and 2nd embodiment. It is a top view which shows the rotor core which concerns on 3rd embodiment. It is a perspective view which shows the integrated core sheet which comprises the rotor core which concerns on 3rd embodiment. It is a perspective view which shows the laminated body which concerns on 3rd embodiment. It is a perspective view which shows the modification of the integrated core sheet which comprises the rotor core which concerns on 3rd embodiment. It is a top view which shows the rotor core which concerns on 4th embodiment. It is (a) top view and (b) partial front view which show a general radial gap type rotary electric machine. It is a top view which shows the rotor core which concerns on 5th embodiment.

  Hereinafter, embodiments of a rotor core according to the present invention will be described with reference to the drawings. In this specification, when it shows with the same code | symbol, it shall show the same structure.

  As shown in FIG. 1, in the rotor core 20a according to the first embodiment, a plurality of magnetic poles 21 arranged in the circumferential direction around the rotation shaft 1 are arranged on the outer periphery of a cylindrical core body 22 and are adjacent to each other. 21 is a split-type inner rotor core in which a core body 22 is split at a plurality of split portions 25 formed between 21. The split-type rotor core has the advantages that the easy axis of magnetization can be made to coincide with the direction in which the magnetic flux flows, and that the core is easy to obtain and the yield is high.

  A plurality of magnet holes 23 are formed in the core body 22, and the core body 22 is magnetized by the magnet 24 (see FIG. 19) accommodated in the magnet holes 23, thereby forming the magnetic pole 21. In the present embodiment, since the outer peripheral surface of the core body 22 and the stator 3 (see FIG. 19) face each other with a gap therebetween, each magnetic pole 21 is disposed on the outer side in the radial direction than the corresponding magnet hole 23. The dividing portion 25 is formed linearly in the radial direction from the axial center O, avoiding the magnet holes 23 adjacent in the circumferential direction, and equally divides the core body 22 in the circumferential direction around the axial center O. . If the division part 25 is formed between each magnetic pole 21 like this embodiment, the dimensional accuracy of the magnet hole 23 can be improved. The number of the magnetic poles 21 is not particularly limited. For example, the design may be changed as appropriate according to the number of slots of the stator core 30 (see FIG. 19), the magnitude of the magnetic force of the magnet 24, the use of the rotating electrical machine 100 (see FIG. 19), and the like. Can do. In the present embodiment, six magnetic poles 21 are provided by embedding two magnets 24 in each of the magnet holes 23 corresponding to the six magnet holes 23 formed in a V shape. .

  Further, as shown in FIG. 2, the rotor core 20 a is composed of a large number of core sheets S having a predetermined shape made of an electromagnetic steel sheet having a thickness of about 0.3 to 0.5 mm, the surface of which is insulated. A laminated surface A is formed by the outer circumferences of the laminated core sheets S. The rotor core 20a includes a welded portion 26 in which one core sheet S and another core sheet S in contact with the sheet surface of the one core sheet S are welded to each other by laser welding, and two welded to each other in the welded portion 26. The receding portion 27 provided on one of the core sheets S is provided on the laminated surface A.

  The welded portion 26 is a portion in which a part of each core sheet S is melted and melted by a predetermined distance in the sheet surface direction. In the welded portion 26, two core sheets S adjacent in the rotation axis direction are fixed to each other. As shown in FIG. 1, the welded portion 26 is formed at the pole center portion of each magnetic pole 21 (the magnetic pole portion 201 of the core sheet S). In other words, the welded portion 26 is formed on the outer periphery of each core sheet S. The “pole center portion” as used herein refers to the vicinity of the center of the magnetic pole 21 formed on the outer periphery of the core sheet S by the magnet 24, including the midpoint in the circumferential direction of each magnetic pole 21 (the center of the outer periphery of each core sheet S). Say. As shown in FIG. 2, the welded portion 26 is formed between two core sheets S adjacent to each other in the rotation axis direction, and at least one welded portion 26 is provided on all the core sheets S. Is formed.

  As shown in FIG. 2A, the welded portion 26 is formed linearly in the rotation axis direction. Or as shown in FIG.2 (b), you may form in the circle | round | yen where a center is located between the lamination | stacking of the two core sheets S adjacent to a rotating shaft direction. When the weld part 26 is linear, the width of the weld part 26 is formed to be narrower than the circumferential width of the receding part 27. In addition, when the welded portion 26 is circular, the diameter of the welded portion 26 is smaller than the circumferential width of the receding portion 27 and is within the thickness range of two core sheets S. The This is to prevent unnecessary formation of the welded portion 26 other than the portion to be welded.

  The receding portion 27 is a recess in which a part of the core sheet S is retracted in the sheet surface direction by a distance longer than the penetration depth of the core sheet S by laser welding. In the receding portion 27, the laser beam irradiated during laser welding is out of focus, so heat input becomes insufficient. For this reason, the receding part 27 becomes a non-welded part. As shown in FIG. 1, similarly to the welded portion 26, the retracted portion 27 is formed at the pole center portion of each magnetic pole 21 (the magnetic pole portion 201 of the core sheet S). In other words, the receding portion 27 is formed on the outer periphery of each core sheet S. In addition, as shown in FIG. 2, the retracted portion 27 is provided in one of the two core sheets S welded to each other in the welded portion 26, and the position where the welded portion 26 is formed. Are provided at different positions.

  The receding portion 27 only needs to have a shape in which the maximum receding distance from the outer periphery of the core sheet S to the sheet surface direction is longer than the penetration depth of the core sheet S by laser welding, and the shape is not particularly limited. . In the present embodiment, a cutout having a circular arc shape in plan view is formed on the outer periphery of the core sheet S as the receding portion 27, but may be, for example, an elliptical arc shape, a polygonal shape, or any other shape.

  In the present embodiment, the welded portion 26 and the retreating portion 27 provided on one of the other core sheets S that are in contact with the sheet surfaces of the two core sheets S welded to each other in the welded portion 26 include a rotating shaft. It is characterized by being arranged adjacent to the direction. Specifically, a welded portion 26 is formed in the direction of the rotation axis across the three core sheets S, and retracted portions 27 are disposed on both sides of the welded portion 26 in the direction of the rotation axis. Further, these retracted portions 27 are arranged adjacent to the other welded portions 26 in the rotation axis direction. That is, in the present embodiment, the welded portions 26 formed in the direction of the rotation axis across the three core sheets S and the retreating portions 27 are alternately arranged linearly on the laminated surface A formed on the outer peripheral surface of the rotor core 20a. It is arranged.

  Further, in the present embodiment, the welded portion 26 and the retracted portion 27 arranged as described above are disposed from one end to the other end in the rotation axis direction at two locations on the laminated surface A that are adjacent to each other in the circumferential direction. ing. At this time, when attention is paid to the three core sheets S that are continuous in the rotation axis direction on the laminated surface A, the following can be said. That is, in one core sheet S provided with the retreating part 27 in one place and another core sheet S disposed between the other core sheet S provided with the retreating part 27 in the other place, The retreating portion 27 is not provided. Moreover, the retreat part 27 is provided in the other location of the core sheet S located in the center among the three core sheets S welded at the weld portion 26 formed at one location.

  That is, in this embodiment, the retreating part 27 provided in one place and the retreating part 27 provided in the other place are alternately arranged with the core sheet S not provided with the retreating part 27 interposed therebetween. Are arranged as follows. If the positional relationship of the receding portion 27 is configured in this way, all of the two core sheets S adjacent in the rotation axis direction are formed in one of two locations that are adjacent to each other in the circumferential direction on the laminated surface A. They are welded to each other only at the welded portion 26. As a result, the stacked layers of all the core sheets S are welded and integrated at any one of the welded portions 26. In this embodiment, the welded portion 26 is provided only on the outer periphery of the core sheet S of the rotor core. However, the welded portion 26 is similarly provided on the inner periphery, or two independent welded portions 26 are provided on the outer periphery. Thus, since the two core sheets S that are in contact with each other are welded at two locations, fixing by welding is more stable. The same applies to the following description, but the description is omitted.

  According to the rotor core 20a according to the first embodiment, in the laser welding, the core sheet S provided with the retreating portion 27 that is not welded even when the laser is irradiated is adopted, and configured as described above, the following is achieved. Such effects can be obtained.

  That is, since the welded portion 26 is formed at a position adjacent to the retreating portion 27 in the rotation axis direction, even when the laser irradiation position deviates to some extent in the rotation axis direction during laser welding, the core sheet S to be welded It is possible to surely prevent the other core sheet S from being short-circuited linearly in the rotation axis direction. Therefore, it is possible to accurately and reliably perform welding with respect to the lamination of the core sheets S having a very small thickness without requiring high-precision work. The effect on misalignment is particularly effective when performing spot welding in which the core sheets S are locally welded.

  In addition, the welding portion 26 and the receding portion 27 are arranged linearly from one end to the other end in the rotation axis direction at two locations on the laminated surface A that are close to each other in the circumferential direction, thereby performing laser by linear continuous welding. Even when welding is performed, all of the laminated core sheets S are integrated by laser welding, and a maximum of three core sheets S in which the welded portion 26 is continuously formed in the rotation axis direction are formed. It can be suppressed to the number of sheets. Thereby, an increase in eddy current can be effectively reduced. Since continuous welding can omit positioning in the direction of the rotation axis (that is, positioning between the core sheets S), it is possible to further increase the efficiency of the work. The same effect can be obtained when laser welding is performed by spot welding.

  Furthermore, since the welding part 26 and the retreat part 27 are formed in the pole center part of each magnetic pole 21 (the magnetic pole part 201 of each core sheet S), the distance from the outer periphery of the core sheet S to the magnet hole part 203 is lengthened. Can be secured. For this reason, the influence which the heat at the time of welding has on the magnet 24 accommodated in the magnet hole 23 can be reduced. In general, eddy currents are likely to occur at the pole center where the magnetic flux density is high, but each core sheet S can be prevented from being short-circuited linearly in the direction of the rotation axis at the pole center of the magnetic pole part 201. Generation of eddy current can be effectively prevented.

  Thus, according to the rotor core 20a which concerns on 1st embodiment, while the effort of welding operation can be saved significantly, the eddy current loss resulting from the short circuit of the core sheet | seat S can be reduced effectively. As a result, it is possible to simultaneously improve the efficiency of the welding operation between the core sheets S and improve the performance of the rotating electrical machine 100.

  Next, an embodiment of a method for manufacturing a rotor core according to the present invention will be described. In the following description, the method for manufacturing the rotor core 20a according to the first embodiment described above will be described as an example.

As shown in FIG. 1, the rotor core 20 a has a plurality of (six in this embodiment) magnetic poles 21 are provided on the outer peripheral side of the magnet hole 23 of the core body 22 in which the divided portions 25 are formed at both ends in the circumferential direction. This is a split rotor core in which the split cores 20D ₁ are arranged circumferentially and joined together. Method of manufacturing a rotor core 20a of the present embodiment is formed in the first step and a first step of forming a split core 20D ₁ through steps of preparing a magnetic steel sheet, punching process, a laminating process, and the welding process a second step of joining a plurality of divided cores 20D ₁ was provided with a.

  First, a punching process for forming the prepared electrical steel sheet into a predetermined shape is performed. In the punching step, the magnetic steel sheet is punched to form a peripheral portion including the outer periphery and the inner periphery of the core sheet S, and a retreat portion 27 in which a part of the outer periphery is retreated in the sheet surface direction by a predetermined distance is a predetermined position on the outer periphery. Formed. Thus, as shown in FIG. 3, the first core sheet S1, the second core sheet S2, and the third core sheet S3 are each formed by punching using a cutting means including one or a plurality of punching dies. In addition, all the core sheets S (S1 to S3) are formed by punching so that the direction in which the magnetic flux flows coincides with the easy axis direction. When the prepared electrical steel sheet is a non-oriented electrical steel sheet, it may be formed by punching so that the direction in which the magnetic flux flows coincides with the rolling direction.

  In the present embodiment, first, a substantially fan-shaped core sheet main body 202 composed of divided portions 25 formed at both ends in the circumferential direction, and concentric arc-shaped outer peripheries and inner peripheries respectively connecting the end portions of the divided portions 25; A core sheet S2 having a V-shaped magnet hole 203 formed in the core sheet main body 202 is formed. In the core sheet S <b> 2, a portion (in particular, the outer peripheral portion of the core sheet main body 202) located on the outer side in the radial direction from the magnet hole 203 of the core sheet main body 202 constitutes the magnetic pole part 201. The first core sheet S1 and the third core sheet S3 are formed by forming the receding portion 27 at a predetermined position with respect to the core sheet S2.

  In the first core sheet S1 and the third core sheet S3, the receding portion 27 is preferably formed in a line-symmetric position in order to improve the working accuracy of the laminating process and the welding process. In the present embodiment, the receding portion 27 is formed at the pole center portion of the magnetic pole portion 201, and is formed symmetrically with respect to the center line connecting the midpoints of the outer periphery and the inner periphery of the core sheet main body 202. However, the position where the receding portion 27 is formed is not particularly limited as long as it is within the outer periphery of the magnetic pole portion 201. For example, in the magnetic pole part 201, the retreating part 27 may be formed at a position shifted from the pole center part to the opposite side of the rotation direction of the rotor 2. In this case, since the weld portion 26 is formed at a position where the magnetic flux density is relatively low, there is an advantage that it is difficult to be affected by eddy current loss due to welding.

  As a method of forming the retreating portion 27, for example, a method of punching and forming by changing the punching position with respect to the core sheet S at a predetermined timing using a movable cutting means can be mentioned. According to this method, there is an advantage that three types of core sheets S1 to S3 can be formed in a desired order without requiring other steps. Alternatively, the core sheet S may be punched at a predetermined punching position at a predetermined timing using a fixed cutting means, and these may be alternately turned over. According to this method, since the one core sheet S can be substantially used as two types of core sheets S by using the symmetry between the first core sheet S1 and the third core sheet S3, the cutting means There is an advantage that the control of can be simplified.

  In the punching process of this embodiment, these three types of core sheets S1 to S3 are regularly formed so as to be arranged in the following order. That is, the first core sheet S1, the second core sheet S2, the third core sheet S3, the second core sheet S2, the first core sheet S1, the second core sheet S2, the third core sheet S3,. Is done. In addition, as long as it forms in such an order, which of three types of core sheet S1-S3 is formed initially is arbitrary.

Next, a laminating step of laminating the first core sheet S1, the second core sheet S2, and the third core sheet S3 obtained by the punching step described above in the rotation axis direction is performed. In the present embodiment, these core sheets S1 to S3, by laminating in the order punched in the punching step, the multilayer body L ₁ as shown in FIG. 4 is obtained, each core sheet S1 to S3 , First core sheet S1, second core sheet S2, third core sheet S3, second core sheet S2, first core sheet S1, second core sheet S2, third core sheet S3,. As long as it is, the method of laminating is arbitrary. Note that the laminate L ₁ is shows a part of a split core 20D _1, the number of core sheets S constituting the laminated body L ₁ is, for example, the rotation axis direction of the thickness of the stator 3, and the rotary electric machine It is determined appropriately according to the usage of 100 or the like.

In the stacking process of the present embodiment, the three types of core sheets S1 to S3 are simply stacked in the punching order, and at the same time, the receding portion 27 is disposed at a desired position. Specifically, the outer periphery of the laminated body L ₁ (i.e., the magnetic pole 21) on the stacking surface A formed, are arranged at two positions close to the circumferential direction, and, at regular intervals in the rotational axis direction It is arranged in a straight line. That is, the position relationship between the receding portion 27 disposed on the stacking surface A of the stack L ₁ in the laminating step of this embodiment are the same as the positional relationship of the respective receding portions 27 in the lamination plane A of the rotor core 20a shown in FIG. 2 become.

Next, the welding step of welding between lamination of the core sheets S1~S3 constituting the laminated body L ₁ obtained by stacking step described above is performed. In the present embodiment, as the laser welding, linear performing continuous welding over from one end to the other end of the rotation axis direction of the stacking surface A of the laminated body L _1, or locally with respect to inter-stacking of each core sheet S1~S3 One of the spot welding performed in the following is performed. In any case, these laser weldings are performed so as to pass through the receding portions 27 that are linearly arranged at predetermined intervals in the rotation axis direction. At this time, it is preferable to pass the position where the retreat distance in the sheet surface direction from the outer periphery of the first core sheet S1 and the third core sheet S3 becomes the maximum in each retreat portion 27. This is to more reliably prevent unnecessary short circuit.

The welding process of the present embodiment, three types of cores in the laminate L ₁ that many core sheets S are stacked consisting sheet S1 to S3, two core sheets adjacent to each other at an arbitrary position in the rotation axis direction Laser welding is performed on the outer periphery of S and a position adjacent to the retreating portion 27 provided on one of the other core sheets S in contact with the sheet surfaces of the two core sheets S in the rotation axis direction. . At this time, all the laminated core sheets S1 to S3 are integrated by laser welding, but the core sheets S that are continuously welded in the direction of the rotation axis can be suppressed to a maximum of three. That is, the positional relationship of the welded portion 26 in the welding step of the present embodiment is formed on the laminating surface A of the laminated body L ₁ is identical to the positional relationship of the welded portion 26 in the laminated surface A of the rotor core 20a shown in FIG. 2 become. The welding process may include other processes such as caulking and varnish impregnation.

As a first process, the split core 20D ₁ as shown in FIG. 5 is formed through such a preparation process, a punching process, a laminating process, and a welding process. Incidentally, although not shown, the stacking surface A, corresponding to the back of the split core 20D ₁ is formed in a linear shape in the rotation axis direction (see FIG. 2 (a)), or, in the rotation axis direction A welded portion 26 is formed in a circular shape (see FIG. 2B) with the center positioned between the two adjacent core sheets S stacked. That is, the laminated surface A formed weld 26 and receding portions 27 each positional relationship and its form on the corresponding to the back of the split core 20D _1, each weld in the laminated surface A of the rotor core 20a shown in FIG. 2 26 And the positional relationship and the form of each retreating part 27 are the same.

Then, as a second step, a plurality of divided cores 20D ₁ formed by the first step described above, each are opposed to the circumferential direction of the split portion 25 provided at both ends of the core body 22 circumferentially The rotor core 20a according to the first embodiment is manufactured by arranging and integrating them by a well-known joining method (for example, caulking, welding, etc.).

  According to the stator core manufacturing method of the present embodiment, the rotor core according to the present invention can be more efficiently produced by adopting the above-described preparation process, punching process, lamination process, and welding process. That is, since the quality accuracy can be maintained even if the operation accuracy in the welding process is reduced, the efficiency of the welding operation can be realized.

  Specifically, since laser welding can be performed by linear continuous welding in the laminating step, positioning in the rotation axis direction (that is, positioning with respect to each core sheet S (S1 to S3) between laminations) is omitted. can do. In addition, even when laser welding is performed by spot welding, positioning is facilitated because high-precision work is not required as in the past. Thereby, further efficiency improvement of the welding operation can be achieved.

  As mentioned above, although embodiment of the rotor core 20a which concerns on 1st embodiment of this invention, and its manufacturing method was described, the rotor core which concerns on this invention, and its manufacturing method can be implemented with another form.

  For example, a form like the rotor core 20b shown in FIG. 6 as 2nd embodiment may be sufficient. As shown in FIG. 7, the rotor core 20 b has one end in the rotational axis direction at three locations where the welded portion 26 and the retracted portion 27 provided on the laminated surface B on the outer periphery are close to each other in the circumferential direction on the laminated surface B. It is characterized by being arranged linearly from the other end to the other end.

  In this embodiment, all the laminated core sheets S are provided with the receding portions 27, and each core sheet S is provided with the receding portions 27 provided on one core sheet S. It arrange | positions so that it may not adjoin to the retreat part 27 provided in the other core sheet | seat S which touches in the rotating shaft direction. For this reason, all of the two core sheets S adjacent in the rotation axis direction are welded to each other only at the welded portion 26 formed at any one of the three locations that are adjacent to each other in the circumferential direction on the laminated surface B. Will be. As a result, the laminations of all the laminated core sheets S are welded and integrated at any one of the welded portions 26.

  Also in the rotor core 20b according to the second embodiment, the same effects as those of the rotor core 20a according to the first embodiment described above can be obtained. In addition, in this embodiment, each welding part 26 is more preferable at the point currently formed only with respect to the two core sheets S adjacent to a rotating shaft direction. That is, the core sheet S to be welded is limited to two, and there is no core sheet S in which the welded portion 26 is continuously formed in the rotation axis direction. Therefore, it is possible to obtain the same effect as in the case of welding only between the laminations of the core sheets S without requiring a highly accurate welding operation. Thereby, the effect of reducing eddy current can be further enhanced.

  Moreover, according to the rotor core 20b which concerns on 2nd embodiment, since the welding part 26 is formed by the arrangement | positioning disperse | distributed regularly for every lamination | stacking of each core sheet | seat S, the influence of the heat | fever at the time of laser welding is disperse | distributed. be able to. Thereby, distortion due to welding heat hardly occurs, and the dimensional accuracy of the rotor core body can be increased.

  Furthermore, according to the rotor core 20b according to the second embodiment, while preventing the core sheet S other than the core sheet S to be welded from being short-circuited linearly in the direction of the rotation axis, more reliably, The number of welds 26) can be increased. For this reason, reduction of eddy current loss and improvement of the mechanical strength of the rotor core body can be realized at the same time.

  Next, a method for manufacturing the rotor core 20b according to the second embodiment will be described. The rotor core 20b can be manufactured by the same method as the method for manufacturing the rotor core 20a described above, except for the following differences. Therefore, the detailed description regarding the process common to the manufacturing method of the rotor core 20a is abbreviate | omitted.

  In the present embodiment, in the punching process, the fourth core sheet S4 is punched and formed as shown in FIG. The fourth core sheet S4 is a center line connecting the midpoints of the outer periphery and the inner periphery of the core sheet main body 202 with respect to the outer periphery (that is, the magnetic pole part 201) of the second core sheet S2 (see FIG. 3B). It can be formed by forming the receding part 27 along. In the punching process of the present embodiment, the first core sheet S1, the third core sheet S3, and the fourth core sheet S4 are regularly and sequentially formed so as to be arranged in this order. In addition, as long as it forms in such an order, the kind of core sheet S formed initially is arbitrary.

Then, by performing the laminating step described above, it is possible to obtain a laminated body L ₂ formed by laminating, as shown in FIG. 9, each core sheet S1, S3, S4 punching order. Further, by performing the welding process described above for the stacking surface B of the laminate L _2, as shown in FIG. 10, the split core 20D ₂ is formed. The positional relationship and form of the welded portion 26 and the receding portion 27 formed on the laminated surface B corresponding to the back surface of the split core 20D ₂ are as follows. It becomes the same as each positional relationship and the form of the retreat part 27.

  As described above, according to the method for manufacturing the rotor core 20b according to the second embodiment, the work accuracy in the welding process is similar to that of the rotor core 20a according to the first embodiment described above, but higher quality accuracy is obtained. Can do. For this reason, it can be said that it is a manufacturing method more suitable by manufacture of the rotor core of this invention.

  Moreover, the rotor core which concerns on this invention WHEREIN: The welding part 26 and the retraction part 27 may be formed in the position different from the pole center part of the magnetic pole part 201 of each core sheet S. For example, as a modification of the first embodiment, a rotor core 20c shown in FIG. 11 may be used. The rotor core 20c is characterized in that a welded portion 26 and a retracted portion 27 are formed between the poles of the magnetic pole 21 (the magnetic pole portion 201 of the core sheet S) adjacent in the circumferential direction. Here, the “inter-polar part” refers to a region where the magnetic flux density is particularly low, including between the magnetic poles 21 adjacent in the circumferential direction (the center of the outer periphery of each core sheet S).

  The rotor core 20c of the present embodiment is a split inner rotor core in which the core body 22 is divided at a plurality of split portions 25 formed at the pole centers of the magnetic poles 21. The dividing portion 25 is formed linearly in the radial direction from the axis O through the apex of the V-shaped magnet hole 23, and the core body 22 is equally divided in the circumferential direction around the axis O. Yes. If the division part 25 is formed in the pole center of each magnetic pole 21 like this embodiment, since the flow of magnetic flux is not inhibited in the division part 25, the magnetic resistance of the core main body 22 can be reduced.

  According to the rotor core 20c according to the present embodiment, the positional relationship and the form of each of the welded portion 26 and the retracted portion 27 formed on the laminated surface C constituting a part of the outer peripheral surface and the form thereof are shown in FIG. The positional relationship and the form of each welded portion 26 and each retracted portion 27 on the laminated surface A are the same. For this reason, the effect similar to the rotor core 20a mentioned above can be acquired. In addition to this, since the welded portion 26 and the retracted portion 27 are formed at the interpolar portion of the magnetic pole portion 201 adjacent in the circumferential direction, it is possible to perform welding while avoiding a portion having a high magnetic flux density. For this reason, the eddy current loss resulting from a short circuit can be reduced more effectively.

  The rotor core 20c according to the present embodiment can be manufactured by the same method as the method for manufacturing the rotor core 20a described above, except that the shape of the core sheet S formed by the punching process is different. Therefore, the detailed description regarding the process common to the manufacturing method of the rotor core 20a is abbreviate | omitted.

  In this embodiment, a substantially fan-shaped core sheet main body 202 composed of divided portions 25 formed at both ends in the circumferential direction, concentric arc-shaped outer peripheries and inner peripheries respectively connecting the end portions of the divided portions 25, and the divided portions 25, a sixth core sheet S6 having a magnet hole portion 203 formed by notches formed symmetrically toward the center line connecting the midpoints of the outer periphery and the inner periphery of the core sheet main body 202 is formed. (See the bold line portion in FIG. 11). Although not shown, the fifth core sheet S5 and the seventh core sheet S7 are formed by forming the retreating portion 27 at a predetermined position with respect to the sixth core sheet S6.

  In the method for manufacturing the rotor core 20c of the present embodiment, the first core sheet S1 in the method for manufacturing the rotor core 20a described above is the fifth core sheet S2, the second core sheet S2 is the sixth core sheet S6, and the third core sheet S3. Can be manufactured in the same manner as the rotor core 20a by replacing each with the seventh core sheet S7.

  Further, as a modification of the second embodiment, a rotor core 20d shown in FIG. 12 may be used. Similarly to the rotor core 20b described above, the rotor core 20d has a rotational axis direction at three locations where the welded portion 26 and the retracted portion 27 provided on the laminated surface D on the outer periphery thereof are adjacent to each other in the circumferential direction on the laminated surface D. It is characterized by being arranged linearly from one end to the other end.

  According to the rotor core 20d according to the present embodiment, the positional relationship and the form of each of the welded portion 26 and the retracted portion 27 formed on the laminated surface D constituting a part of the outer peripheral surface thereof and the form thereof are illustrated in FIG. This is the same as the positional relationship and form of each welded portion 26 and each retracted portion 27 on the laminated surface B. For this reason, the effect similar to the rotor core 20b mentioned above can be acquired. In addition to this, the effect obtained by the rotor core 20c described above, that is, the effect of reducing eddy current loss due to a short circuit can be further enhanced.

  Furthermore, as another modification of the first and second embodiments, a rotor core 20e shown in FIG. 13 may be used. The rotor core 20e is characterized in that the dividing portion 25 is formed so as to avoid the pole center portion of each magnetic pole 21. In the present embodiment, the dividing portion 25 in each magnetic pole 21 has a predetermined angle on the opposite side of the rotation direction of the rotor 2 (see the arrow in FIG. 13) from the pole center portion of the magnetic pole 21 with respect to the radial direction of the core body 22. It is inclined by θ. According to the rotor core 20e according to the present embodiment, since the split portion 25 is formed avoiding the pole center portion from the rotation direction of the magnetic pole 21 having a high magnetic flux density, the magnetic resistance of the core body 22 is more effectively reduced. can do.

  The positional relationship and the form of each of the welded portion 26 and the retracted portion 27 formed on the laminated surface E constituting a part of the outer peripheral surface of the rotor core 20e according to the present embodiment and the form thereof are the laminated layers of the rotor core 20a shown in FIG. The positional relationship and the form of each welded portion 26 and each retracted portion 27 on the surface A may be the same, or each welded portion 26 and each retracted portion 27 on the laminated surface B of the rotor core 20b shown in FIG. The positional relationship and the form thereof may be the same.

  Further, in the rotor core 20e of the present embodiment, the welded portion 26 and the retracted portion 27 are formed at the pole center portion of the magnetic pole portion 201 of each core sheet S, but the welded portion is similar to the rotor cores 20c and 20d described above. 26 and the receding part 27 may be formed in the interpolar part of the magnetic pole part 201 adjacent in the circumferential direction.

  Furthermore, the rotor core 20e according to the present embodiment is the same method as the method for manufacturing the rotor cores 20a to 20d described above except that the shape of the core sheet S formed by the punching process (see the thick line portion in FIG. 13) is different. Can be manufactured.

  The rotor cores 20a to 20e of the above-described embodiments are all divided rotor cores, but the present invention can also be adopted for so-called integrated rotor cores.

  For example, the third embodiment may be a rotor core 20f shown in FIG. The rotor core 20f is an integral rotor core in which the split part 25 is not formed in the core body 22. The rotor core 20f of the present embodiment includes six V-shaped magnet holes 23 provided in the cylindrical core body 22, and the six-pole magnetic poles 21 corresponding to the magnet holes 23 correspond to the magnet holes 23, respectively. Are arranged at equal intervals in the circumferential direction on the outside in the radial direction. Although not shown, a welded portion 26 and a retracted portion 27 are formed on the laminated surface F formed on each magnetic pole 21 in the same form as the laminated surface B shown in FIG. Also in the rotor core 20f according to the third embodiment, the same effect as that of the rotor core 20f described above can be obtained.

  Next, a method for manufacturing the rotor core 20f according to the third embodiment will be described. The manufacturing method shown below can be used only for an integral rotor core. The manufacturing method of the rotor core 20f of the present embodiment includes a punching process, a stacking process, and a welding process. In the stacking process, the core sheet S having the same shape punched and formed by the punching process is already stacked. The core sheet S is laminated by being rotated relative to the core sheet S by a predetermined angle in the circumferential direction.

  First, an integrated core sheet S8 as shown in FIG. 15 is formed by performing a punching process. The integrated core sheet S8 has six V-shaped magnet hole portions 203 provided in the annular core sheet main body 202, and the six magnetic pole portions 201 corresponding to each magnet hole portion 203 are The magnet holes 203 are arranged at equal intervals in the circumferential direction on the outer side in the radial direction. Each magnetic pole part 201 is formed with a receding part 27.

  Each magnetic pole part 201 is classified into the following three types of magnetic pole parts 201 on the basis of the relative positional relationship of the receding part 27 with respect to the center line extending in the radial direction through the middle point in the circumferential direction. That is, when viewed from the center point of the annular core sheet main body 202 (that is, the axis O of the rotating shaft 1), the first magnetic pole portion 201a in which the retreating portion 27 is formed on the center line, the left side of the center line A second magnetic pole part 201b in which the receding part 27 is formed at a position shifted to, and a third magnetic pole part 201c in which the receding part 27 is formed at a position shifted to the right side with respect to the center line.

  In the punching process of the present embodiment, the receding portion 27 is punched and formed so that the magnetic pole portions 201 of the same type among the three types of magnetic pole portions 201a, 201b, and 201c are arranged to face each other. Thereby, the magnetic pole part 201 provided in integrated core sheet S8 which concerns on this embodiment is located in the circumferential direction in order of the 1st magnetic pole part 201a, the 2nd magnetic pole part 201b, and the 3rd magnetic pole part 201c clockwise. Is arranged.

  Unlike the punching process in the manufacturing method of the split rotor core described above, in the punching process of this embodiment, the integrated core sheet S8 having the same shape may be formed sequentially, so that the punching order is irrelevant. Therefore, in this embodiment, the retreat part 27 can be formed singly using the fixed cutting means consisting of one mold.

Then, by performing the laminating step, as shown in FIG. 16, a plurality of integral core sheet S8 is laminated body L ₃ stacked in the rotation axis direction is obtained. In the laminating process of the present embodiment, the integrated core sheet S8 having the same shape punched and formed by the punching process is rotated relatively by a predetermined angle in the circumferential direction with respect to the other integrated core sheet S8 already stacked. Are stacked. The rotation angle at this time is appropriately set and changed according to the number of poles of the magnetic pole part 201.

In the stacking process of the present embodiment, the integrated core sheet S8 that has already been stacked is replaced with the central point of the annular core sheet body 202 (that is, the axis of the rotary shaft 1) with respect to the newly stacked integrated core sheet S8. The integral core sheets S8 having the same shape are sequentially laminated while rotating clockwise or counterclockwise by 60 degrees around the center O). Obtained on the laminated surface F is formed in each magnetic pole 21 of the laminated body L ₃ Thus, receding portion 27 is the same position as on the stacking surface B formed on the magnetic poles 21 of the laminated body L ₂ shown in FIG. 9 Placed in a relationship. Here, it is the magnetic pole pitch (an angle obtained by dividing 360 degrees by the number of poles of the magnetic pole part 6) that is rotated by 60 degrees, and even when rotated by 60 degrees, the planar shape of the core sheet S8 is laminated in the same manner. This is because that.

Finally, for each pole 21 of the laminated body L ₃ obtained by laminating step, by performing the above-mentioned welding process, all of the integrated core sheet S8 laminated are integrated by welding, the third embodiment The rotor core 20f according to the embodiment is manufactured.

  According to the method for manufacturing the rotor core 20f of the present embodiment, the punching process can be greatly simplified. That is, in the punching process, it is only necessary to form the core sheet S8 having the same shape, so that the processes such as positioning of the mold and selection of the mold can be omitted or simplified. Moreover, since the receding portion 27 can be simultaneously punched and formed on the outer periphery of each core sheet S8 (predetermined position of each magnetic pole portion 201) with one mold, the equipment cost can be reduced.

  Moreover, the manufacturing method of the rotor core 20f described above can be widely used according to the shape of the core sheet S, the number of poles of the magnetic pole part 201, and the position of the retreat part 27.

  For example, in the manufacturing method of the rotor core 20f described above, if a core sheet S9 as shown in FIG. 17 is employed, a rotor core 20g (not shown) according to a modification of the third embodiment can be manufactured. The difference between the rotor core 20f according to the third embodiment and the rotor core 20g according to the modification is that a welded portion 26 and a retracted portion 27 are formed for each pole pair in the magnetic pole portion 201. Specifically, when the number of poles is P, the number of pole pairs is P / 2, and the welded portion 26 and the retracted portion 27 are provided every 720 / P (°). In this embodiment, P = 6, and it is provided every 720/6 = 120 °.

  As shown in FIG. 17, the core sheet S <b> 9 is provided with a six-pole magnetic pole part 201. Generally, the polarity (N pole, S pole) of each magnetic pole provided in the rotor 2 is alternately arranged in the circumferential direction. If this N pole and S pole are made into one pole pair, it can be paraphrased that the rotor core 20g of this embodiment is provided with the magnetic pole 21 of 3 pole pairs. That is, the core sheet S9 of this embodiment is provided with the magnetic pole part 201 having a three-pole pair.

  In the present embodiment, the core sheet main body 202 of the core sheet S9 has magnetic pole portions 201 in which the retreating portions 27 are formed and magnetic pole portions 201 in which the retreating portions 27 are not formed alternately arranged in the circumferential direction. In addition, the magnetic pole part 201 in which the receding part 27 is formed has the first magnetic pole part 201a, the second magnetic pole part 201b, and the third magnetic pole part 201c arranged in this order in the clockwise circumferential direction. ing. Therefore, in the magnetic pole 21 of the rotor core 20g of the present embodiment, the welded portion 26 and the retracted portion 27 are formed only in either the N-pole or S-pole magnetic pole 21. At this time, the laminated surface (not shown) of each magnetic pole 21 in which the welded portion 26 and the receding portion 27 are formed is formed in the same form as the laminated surface B shown in FIG.

  If the welded portion 26 and the retracted portion 27 are formed for each pole pair in the magnetic pole portion 201 as in the rotor core 20g of the present embodiment, the amount of magnetic flux passing between them is constant, which further increases the generation of eddy currents. Can be reduced. Thereby, eddy current loss is further reduced, and the performance of the rotating electrical machine 100 can be further improved.

  In the case of manufacturing the rotor core 20g of the present embodiment, in the stacking step, the integrated core sheet S9 that has already been stacked is replaced with the center point ( That is, the integral core sheets S9 having the same shape may be sequentially laminated while rotating clockwise or counterclockwise by 120 degrees around the axis O) of the rotating shaft 1. Here, it is the pole pair pitch (an angle obtained by dividing 360 degrees by the number of pole pairs 3 of the magnetic pole portions) that is rotated by 120 degrees, and even when rotated by 120 degrees, the planar shape of the core sheet S9 is the same layered. Because it is done.

  Moreover, in the manufacturing method of the rotor core 20f mentioned above, the rotor core 20h (illustration omitted) which concerns on 4th embodiment can also be manufactured by employ | adopting core sheet S10 as shown in FIG. The core sheet S <b> 10 has four magnet hole portions 203 provided in the annular core sheet main body 202, and a four-pole magnetic pole portion 201 corresponding to each magnet hole portion 203 is formed more than each magnet hole portion 203. They are arranged at equal intervals in the circumferential direction on the outer side in the radial direction. In the four-pole magnetic pole part 201, the two-pole magnetic pole part 201 in which the retreating part 27 is not formed and the two-pole magnetic pole part 201 in which the retreating part 27 is formed are opposed to each other. In addition, one of the two magnetic pole portions 201 where the receding portion 27 is formed corresponds to the second magnetic pole portion 201b described above, and the other corresponds to the third magnetic pole portion 201c.

  As described above, the number of magnetic poles 21 of the rotor core 20h is four. Therefore, when the rotor core 20g of the present embodiment is manufactured, in the stacking step, the integrated core sheet S10 that has already been stacked is replaced with the center of the annular core sheet main body 202 with respect to the newly stacked integrated core sheet S10. The integral core sheets S10 having the same shape may be sequentially stacked while rotating 90 degrees clockwise or counterclockwise around the point (that is, the axis O of the rotating shaft 1).

  Thus, using the core sheet S10 shown in FIG. 18, a welded portion 26 and a retreating portion 27 are formed on the laminated surface (not shown) of each magnetic pole 21 of the rotor core 20h manufactured by the above-described method for manufacturing the rotor core 20f. These are formed in the same form as the laminated surface A shown in FIG.

  In the rotor cores 20f, 20g, and 20h described above, the welded portion 26 and the retracted portion 27 are formed at the pole center portions of the magnetic pole portions 201 of the core sheets S8, S9, and S10, but are adjacent in the circumferential direction. It can also be implemented in a form that is formed between the pole portions of the magnetic pole portion 201. That is, when using the integral core sheet S, if the relative positional relationship in the circumferential direction of the respective receding portions 27 formed on the outer periphery of the core sheet main body 202 is the same, the integral rotor core according to the above-described embodiment. The rotor core according to the present invention can be manufactured using the manufacturing method.

  The rotor cores 20a to 20h according to the embodiments of the present invention can be used in a rotating electrical machine 100 as shown in FIG. A rotating electrical machine 100 according to the present embodiment includes a so-called radial that includes a rotor 2 that is rotatably arranged around a rotating shaft 1 and a stator 3 that is disposed with a gap in the radial direction of the rotor 2. It is a gap-type rotating electrical machine.

  The rotor 2 is formed by laminating a plurality of rotor core sheets S (see FIG. 19 (b)) formed of electromagnetic steel plates in a predetermined shape in the direction of the rotation axis, and the rotation axis so as to be rotatable around the axis O. 1 is provided with a rotor core 20 fixed to 1. As the rotor 2, for example, an embedded magnet type (IPM type) in which a magnet 24 is embedded in a magnet hole 23 provided at a predetermined position of the rotor core 20 as shown in FIG. A configuration such as a surface magnet type (SPM type) in which the magnet 24 is disposed on the surface (the surface facing the stator 3) can be arbitrarily selected. Alternatively, a switched reluctance type (SR type) configuration in which the magnet 24 is omitted and the rotor core 20 is provided with salient poles (not shown) may be employed as the rotor 2.

  The stator 3 is formed by laminating a plurality of stator core sheets (not shown) formed of electromagnetic steel sheets in a predetermined shape in the rotation axis direction, and has a plurality of teeth 31 arranged in the circumferential direction around the rotation axis 1. And a winding 32 wound around each tooth 31 via an insulator (not shown). The stator 3 shown in FIG. 19 is configured by concentrated winding in which a single-phase winding 32 in a three-phase alternating current is wound around a single tooth 31. You may be comprised by the distributed winding by which the coil | winding 32 of a different phase is arrange | positioned at the slot 33 formed between.

  The rotating electrical machine 100 according to the present embodiment includes any one of the rotor cores 20a to 20h according to the above-described embodiments as the rotor core 20 constituting the rotor 2. Therefore, according to the rotating electrical machine 100 of the present embodiment, the eddy current loss can be significantly reduced, so that the performance as the rotating electrical machine can be improved.

  It should be noted that the present invention can be implemented in a mode in which various improvements, modifications, or variations are added based on the knowledge of those skilled in the art without departing from the spirit of the present invention. Moreover, you may implement with the form which substituted any invention specific matter to the other technique within the range which the same effect | action or effect produces.

  For example, the rotor cores 20a to 20h in each of the embodiments described above are all inner rotor cores, but the present invention can also be employed in so-called outer rotor cores.

  Specifically, the rotor cores 20i and 20j shown in FIG. 20 may be used as the fifth embodiment. The rotor cores 20 i and 20 j are outer rotor cores in which the magnetic poles 21 are formed on the inner peripheral side of the core body 22. In the present embodiment, ten magnet holes 23 provided in the cylindrical core body 22 are provided, and the 10-pole magnetic poles 21 corresponding to the magnet holes 23 are located on the inner side in the radial direction than the magnet holes 23. They are arranged at equal intervals in the circumferential direction.

  In the present embodiment, a rotor core 20i shown in FIG. 20A may be a split-type rotor core in which a plurality of split portions 25 are formed in the core body 22, or the rotor core shown in FIG. 20B. The integrated rotor core in which the split part 25 is not formed in the core body 22 may be used as in 20j. Moreover, in the rotor core 20i, the division part 25 may be formed in the pole center part of each magnetic pole 21 (magnetic pole part 201 of a core sheet), or the magnetic pole 21 (magnetic pole part of the core sheet S) adjacent to the circumferential direction. 201).

  Further, in the present embodiment, the positional relationship and the form of each of the welded portion 26 and the retracted portion 27 formed on the laminated surface constituting a part of the outer peripheral surface of the rotor cores 20i, 20j are the same as those of the rotor core 20a shown in FIG. The positional relationship and the form of each welded portion 26 and each retracted portion 27 on the laminated surface A may be the same, or each welded portion 26 and each retracted portion 27 on the laminated surface B of the rotor core 20b shown in FIG. Each positional relationship and its form may be the same.

  Furthermore, in this embodiment, the welding part 26 and the retreat part 27 may be formed in the pole center part of the magnetic pole part 201 of each core sheet S which comprises the rotor cores 20i and 20j, or it adjoins the circumferential direction. It may be formed between the pole portions of the magnetic pole portion 201. In addition to this, the welded portion 26 and the retracted portion 27 may be formed on either or both of the inner periphery and the outer periphery of the core body 22 of the rotor cores 20i and 20j.

  The rotor cores 20i and 20j of the present embodiment can also be manufactured using the above-described rotor core manufacturing method according to the present invention. In addition, the same operations and effects as described above can be obtained, and the object of the present invention can be achieved. can do.

  In the present invention, the receding portion 27 is provided in order to prevent the adjacent core sheet S from being welded even if the laser is irradiated during laser welding. Therefore, the retreating part 27 only needs to retreat a predetermined distance with respect to the welding part 26. That is, the welded portion 26 is formed as a convex portion protruding in the radial direction, and the retreating portion 27 is a part of a flat portion formed on the outer periphery or inner periphery of each core sheet S or a part of an arc-shaped outer periphery or inner periphery. It may be comprised. Alternatively, instead of the retreating portion 27, an advancement portion in which a part of the outer periphery or inner periphery of each core sheet is advanced in the sheet surface direction in order to defocus the laser may be provided at a position corresponding to the retreating portion 27. Good.

  Even if it is such a form, since it can prevent that the core sheet S short-circuits linearly in the rotating shaft direction, while obtaining the same operation and effect as described above, the object of the present invention can be achieved. .

1: Rotation axis 2: rotor 3: the stator 20,20A～20j: a rotor core 30: stator core 20D _1, 20D _2: split core 21: magnetic pole 22: the core body 23: magnet hole 24: magnet 25: dividing portion 26: weld 27: Retraction part 31: Teeth 32: Winding 33: Slot 100: Rotary electric machine 201: Magnetic pole part 202: Core sheet main body 203: Magnet hole part S, S1 to S10: Core sheet A, B, C, D, E, F: Laminated surface L ₁ , L ₂ , L ₃ : Laminated body O: Axis

Claims (9)

A rotor core formed by laminating a plurality of core sheets formed of electromagnetic steel sheets in a predetermined shape in the rotation axis direction,
A welded portion formed on the outer periphery or inner periphery of each core sheet, wherein one of the core sheets and another core sheet in contact with the sheet surface of the one core sheet are welded to each other by laser welding;
Provided on one or both of the two core sheets welded to each other in the welded portion, at a position different from the position where the welded portion is formed, by a distance longer than the penetration depth of the core sheet by laser welding. A retreating part in which a part of the outer periphery or inner periphery of the core sheet is retreated in the sheet surface direction,
The welded portion and the receding portion provided on one or both of the other core sheets contacting the sheet surfaces of the two core sheets welded to each other at the welded portion are disposed adjacent to each other in the rotation axis direction. Rotor core characterized by being made. Provided with a laminated surface formed by each outer periphery or inner periphery of the plurality of core sheets,
The welded portion and the receding portion are linearly arranged from one end to the other end in the rotation axis direction at two or three locations that are adjacent to each other in the circumferential direction on the laminated surface,
All of the two core sheets adjacent in the rotation axis direction are welded to each other only at the welded portion formed at any one of two or three locations adjacent to each other in the circumferential direction on the laminated surface. The rotor core according to claim 1, wherein:   The retreating portion provided in one core sheet is disposed so as not to be adjacent to the retreating portion provided in another core sheet in contact with the sheet surface of the one core sheet in the rotation axis direction. The rotor core according to claim 1 or 2. The core sheet includes a plurality of magnetic pole portions arranged in the circumferential direction,
The said welding part and the said retreat part are formed in the pole center part of the said magnetic pole part of each core sheet, or the interpolar part of this magnetic pole part adjacent to the circumferential direction, The Claim 1 characterized by the above-mentioned. 4. The rotor core according to any one of 3.   The rotor core according to claim 4, wherein the welded portion and the retracted portion are formed for each pole pair in the magnetic pole portion. A method of manufacturing a rotor core comprising a plurality of core sheets formed of electromagnetic steel sheets in a predetermined shape and laminated in a rotational axis direction,
Preparing the electromagnetic steel sheet;
The magnetic steel sheet is punched to form a peripheral portion including an outer periphery and an inner periphery of the core sheet, and a retreated portion in which a part of the outer periphery or the inner periphery is retreated in the sheet surface direction by a predetermined distance is formed on the outer periphery or the inner periphery. A punching process of the core sheet to be formed at a predetermined position;
By laminating each core sheet obtained by the punching step so that one or both of the two core sheets adjacent to each other in the rotation axis direction become the core sheet provided with the receding portion, the receding portion is predetermined. A laminating process arranged at a position;
One or both of the other core sheets in contact with the respective sheet surfaces of the two core sheets at the outer periphery or inner periphery of the two core sheets adjacent to each other in the rotation axis direction. And a welding step in which a position adjacent to the retreating portion provided in the rotating shaft direction is welded by laser welding. In the lamination step,
The retreating part provided in one core sheet and the retreating part provided in one or both of the one core sheet and another core sheet adjacent in the rotation axis direction are adjacent to each other in the circumferential direction. Or placed in three places,
The laminated surface formed by each outer periphery or inner periphery of the plurality of core sheets stacked, wherein the receding portions are respectively arranged in a straight line with a predetermined interval in the rotation axis direction. A method for producing a rotor core according to claim 6. In the punching process,
The movable cutting means that can change the punching position with respect to the electromagnetic steel sheet makes the punching position with respect to each core sheet different, and forms the retracted portion at a predetermined position on the outer periphery or inner periphery of each core sheet. The manufacturing method of the rotor core of Claim 6 or Claim 7. In the lamination step,
The core sheet having the same shape punched and formed by the punching process is laminated by rotating it relative to the already laminated core sheet by a predetermined angle in the circumferential direction. The method for producing a rotor core according to any one of 8.

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