JP4242435B2 - Laminated iron core and method for manufacturing the same - Google Patents

Description

The present invention relates to a laminated core in which a plurality of segment core pieces continuous in a strip shape are spirally wound and laminated, and a method for manufacturing the same.

Conventionally, as a method for improving the yield of iron core materials (for example, strips) used in the manufacture of laminated iron cores, when punching iron core pieces from iron core material, a plurality of segment core pieces that are continuous in a strip shape are formed by punching. A so-called wound iron core is known in which a laminated iron core is manufactured by laminating this while being wound.
Specifically, arc-shaped segment core pieces having a predetermined number of slots are punched out of the core material with a die in a state where the pieces are connected to each other via a connecting member. Then, the connecting member formed on the outer peripheral side is bent, and a plurality of continuous segment core pieces are spirally wound and laminated while matching the side end portions of the adjacent segment core pieces. In the lamination direction of the laminated cores, the connecting members are shifted to different positions, and the segment core pieces and the connecting members are arranged adjacent to each other (see, for example, Patent Document 1, Patent Document 2, and Patent Document 3).

Japanese Patent Laid-Open No. 1-264548 JP-A-8-196061 JP-T-2004-505595

However, when the connecting member is bent in order to arrange a plurality of segment core pieces in an annular shape, a bulging portion is generated in the thickness direction of the connecting member, and a gap is generated between the segment core pieces in which the bulging portions are stacked. The thickness of the manufactured laminated iron core varied. For example, in the assembly of a motor using a laminated iron core, this gap may cause an extra pressurizing process to eliminate the gap, or cause a reduction in efficiency or vibration of the motor, which adversely affects the quality of the motor. .

The present invention has been made in view of such circumstances, and provides a laminated iron core capable of producing a high-quality product with high efficiency without being affected by the bulging of the connecting member in the thickness direction, and a method for producing the same. Objective.

The laminated core according to the first aspect of the present invention that meets the above-described object is a plurality of the segment cores that are continuous while the side end portions of the adjacent segment core pieces joined together by the connecting members are folded and joined together. In a laminated iron core in which pieces are spirally wound and laminated,
The connecting member is formed so as to connect the outer peripheral portions of the adjacent segment core pieces, and a radially bulging portion formed on the radially outer side when the connecting member is bent is formed on the radially outer side of the connecting member. A recess notch that fits in the outer circle of the laminated core is provided, and on the radially inner side, an inner notch that forms a bending position of the connecting member is provided,
The connecting member is provided with a through hole that divides the connecting member into a radially outer region and a radially inner region, and suppresses a swelling in the thickness direction that occurs when the connecting member is bent,
In addition, a radial width W1 of the radially inner region formed in the connecting member radially inward with the through hole as a center, and the connecting member formed in radially outward with the through hole as a center. The radial width W2 of the radially outer region is 10% to 40% of the radial width of the connecting member .

In the laminated iron core according to the first aspect of the present invention, it is preferable that a thin portion connected to the through hole is formed in the connecting member.
In the laminated iron core according to the first aspect of the present invention, any one or two of the width W1 of the radially inner region and the width W2 of the radially outer region of the connecting member formed by the through holes is extended in the circumferential direction. It is preferable to have the same width.
In the laminated core according to the first aspect of the present invention, it is preferable that the width W1 of the radially inner region of the connecting member is narrower than the width W2 of the radially outer region of the connecting member.
In the laminated core according to the first aspect of the present invention, it is preferable that the side end portions of the adjacent segment core pieces are arranged close to each other with a gap.

The manufacturing method of the laminated core according to the second aspect of the present invention includes a punching step of forming a plurality of segment core pieces in a state of being connected to each other by a connecting member, and bending the connecting member adjacent to each other. In the manufacturing method of the laminated core having an annular forming step of spirally winding and laminating the plurality of continuous segment core pieces while aligning the side end portions of the segment core pieces,
The connecting member is formed so as to connect outer peripheral portions of the adjacent segment core pieces, and in the punching step , the connecting member is divided into a radially outer region and a radially inner region, A through-hole that suppresses swelling in the thickness direction that occurs when the connecting member is bent is formed, and the radial width of the radially inner region that is formed radially inward of the connecting member around the through-hole W1 and a radial width W2 of the radially outer region formed radially outside the through hole in the connecting member are 10% or more and 40% or less of the radial width of the connecting member, respectively. There is .

In the method for manufacturing a laminated core according to the second invention, a thin-walled portion connected to the through hole is formed on the connecting member at the same time as the through hole is formed, before the formation, or after the formation. Is preferred.

In the laminated core according to any one of claims 1 to 5 and the method for producing a laminated core according to claim 6, a through-hole is provided in a connecting member that mutually connects adjacent segment core pieces, so that the connecting member is bent when the connecting member is bent. Bulge in the thickness direction can be suppressed. As a result, it is possible to suppress and further prevent the formation of a gap between a plurality of laminated segment core pieces, thereby facilitating quality control of the laminated core and increasing the efficiency of the motor using the laminated core. In addition, the motor quality can be improved by preventing the occurrence of vibration.

In particular, in the laminated iron core according to claim 2, when the width W1 of the radially inner region of the connecting member is set to the same width in the circumferential direction, the concentration of compressive stress generated in the radially inner region when the connecting member is bent is reduced. Can be suppressed. Thereby, it can suppress that the swelling of the thickness direction of a connection member generate | occur | produces locally.
Moreover, when making the width W2 of the radial direction outside area | region of a connection member the same width over the circumferential direction, the concentration of the tensile stress which arises in a radial direction outer area | region at the time of bending of a connection member can be suppressed. Thereby, the fracture | rupture of the connection member which becomes easy to generate | occur | produce at the time of bending of a connection member can be suppressed.

In the laminated iron core according to the third aspect, the width W1 of the radially inner region of the connecting member is made smaller than the width W2 of the radially outer region, so that the compressive stress generated in the radially inner region can be reduced when the connecting member is bent. Further, the bulging of the connecting member in the thickness direction can be further suppressed, and the breaking of the connecting member can also be suppressed.
The laminated iron core according to claim 5 is arranged adjacent to the side end portions of the adjacent segment core pieces, so that contact between the side end portions can be prevented, so that variation in the circumferential pitch of each segment core piece can be prevented, For example, the displacement of the caulking position of the segment core pieces in the stacking direction can be prevented. In addition, by arranging them close in this way, for example, even when a die blade for punching a segment core piece wears out and burrs are generated at the side end, the contact can be prevented, and the circumference of each segment core piece can be prevented. It is possible to prevent the deviation of the direction pitch.

Next, embodiments of the present invention will be described with reference to the accompanying drawings for understanding of the present invention.
Here, FIG. 1 is a plan view of a laminated core according to an embodiment of the present invention, FIG. 2 is a partial plan view showing a state before lamination of segment core pieces of the laminated core, and FIG. 3 is a connection of the laminated cores. Explanatory drawing of the formation method of the thin part of a member, Drawing 4 (A)-(D) is a partial top view of a connecting member concerning a modification, respectively.

As shown in FIGS. 1 to 3, a laminated core 10 according to an embodiment of the present invention is a side end portion of adjacent segment core pieces 13 joined together by a connecting member 12 formed on an outer peripheral portion 11. 14 is a stator laminated core (also referred to as a stator) in which a plurality of continuous segment core pieces 13 are spirally wound and laminated while the connecting member 12 is bent and aligned, and the connecting member 12 is connected to the connecting member 12. The through-hole 15 which suppresses the swelling of the thickness direction produced at the time of bending is provided. This will be described in detail below.

The laminated iron core 10 is formed from a plurality of segment core pieces 13 joined by a connecting member 12 from a magnetic steel sheet (not shown) having a thickness of, for example, about 0.5 mm or less (0.35 mm in the present embodiment). 1. As shown in FIGS. 1 and 2, the punched continuous segment core pieces 13 are wound and sequentially caulked and laminated. Here, as a method of laminating a plurality of segment core pieces, any one of caulking, welding, and adhesion can be applied, or any two or more can be used in combination.
Each segment core piece 13 is provided with a plurality of slots 16 on the inner side in the radial direction to form a magnetic pole piece portion 17 and on the outer side in the radial direction, a yoke piece portion 18 is formed.

Between adjacent segment core pieces 13, a connecting member 12 that couples the segment core pieces 13 at the outer peripheral portion 11 is provided.
As shown in FIG. 2, the radial width Wt of the connecting member 12 is, for example, about 0.3 mm to 2 mm (0.5 mm to 1 mm in this embodiment).
On the outer side in the radial direction of the connecting member 12, there is provided a recess notch 20 in which a radially expanded portion 19 formed on the outer side in the radial direction when the connecting member 12 is bent is accommodated in the outer circle of the laminated core 10. For this reason, as shown in FIG. 2, before the connection member 12 is bent, the outer periphery of the connection member 12 is recessed radially inward.

Further, on the radially inner side of the connecting member 12 (the radially outer region of the side end portion 14), as shown in FIGS. 1 and 2, the inner notch in which the shape of the connecting member 12 before being bent is an arc shape. 21 is provided, and a folding start point (folding position) is formed at the innermost portion 22 of the inner notch 21. The shape of the inner notch may be, for example, an inverted U shape or an inverted V shape in plan view.
The inner notch 21 has an elliptical shape after the connecting member 12 is bent, and forms a gap between the radially outer regions of the side end portions 14 of the adjacent segment core pieces 13. The radially inner regions of the side end portions 14 of the adjacent segment core pieces 13 can be matched without causing the outer regions in the direction to interfere with each other.

As shown in FIG. 2, the connecting member 12 is provided with a through hole 15 in which the shape of the connecting member 12 before being bent is a rectangle (may be a square). The inner width Wh in the radial direction of the through-hole 15 is about 20% to 80% (preferably 30% to 70%) of the radial width Wt of the connecting member 12.
As a result, a radially inner region (hereinafter also simply referred to as an inner region) 23 and a radially outer region (hereinafter also simply referred to as an outer region) 24 are formed in the radial direction of the connecting member 12 with the through hole 15 as the center. The The width W1 of the radially inner region 23 and the width W2 of the radially outer region 24 are 10% or more and 40% or less of the radial width Wt of the connecting member 12 according to the inner width Wh of the through-hole 15 ( Preferably, it is about 15% or more and 35% or less.

Note that the inner region 23 of the connecting member 12 is subjected to compressive stress when the connecting member 12 is bent and easily swells in the thickness direction. Therefore, as shown in FIG. 3, a coining process for pressing the punch 25 against the inner region 23 is performed. Preferably it is done.
In FIG. 3, the punch 25 is also pressed against the outer region 24, and as a result, the crush margins 26 and 27 of the inner region 23 and the outer region 24 move to the through hole 15 side and are connected to the through hole 15. A thin portion 28 is formed. The thickness of the thin portion 28 is the thinnest portion, and is 70% or more and 95% or less, preferably 80% or more and 95% or less (the pressing amount is, for example, about 30 μm or more and 40 μm or less) of the original thickness of the connecting member 12. .
When pressing, it is preferable to use a punch with an inclined pressing surface, and gradually increase the thickness of the connecting member 12 from the radially inner side to the outer side of the connecting member 12.
In addition, since the thin portion may be formed at least in the inner region that communicates with the through hole of the connecting member, it may be partially formed in the outer region that communicates with the through hole, or may be formed so as to surround the periphery of the through hole. You can also.

The through-hole 15 suppresses the swelling in the thickness direction that occurs when the connecting member 12 is bent, and the thin-walled portion 28 further enhances the effect. For this reason, it is good also considering a connection member and a thin part as the following structures.
The connecting member 30 shown in FIG. 4A has a width of a radially inner region (hereinafter also simply referred to as an inner region) 32 of the connecting member 30 separated by the through hole 31, that is, an inner side from the inner peripheral edge 33 of the through hole 31. The width W <b> 1 to the notch 21 (the inner peripheral edge 34 of the connecting member 30) is the same width over the circumferential direction of the connecting member 30. Further, regarding the width of the radially outer region (hereinafter also referred to simply as the outer region) 35 of the connecting member 30, that is, the width W2 from the outer peripheral edge 36 of the through hole 31 to the recess notch 20 (the outer peripheral edge 37 of the connecting member 30). Also, the same width is provided over the circumferential direction of the connecting member 30.

Thereby, the stress concentration that has conventionally occurred in the narrow portion between the inner region and the outer region can be distributed substantially uniformly over the circumferential direction of the connecting member 30.
The width W1 of the inner region 32 and the width W2 of the outer region 35 of the connecting member 30 are the same width, but only one of them may be the same width in the circumferential direction of the connecting member 30. .
Here, considering that the compressive stress is likely to be generated in the inner region 32 and the tensile stress is likely to be generated in the outer region 35 when the connecting member 30 is bent, the width (minimum width) W1 of the inner region 32 is set to the outer side. It is preferable to make the width smaller than the width (minimum width) W2 of the region 35.
In addition, the formation region of the thin portion is a portion excluding both sides in the circumferential direction of the inner region 32, that is, a region (crushing range) surrounded by a dotted line.

The connecting member 40 shown in FIG. 4B is formed with through holes 42 having apexes on both sides in the circumferential direction on the radially outer region (hereinafter, also simply referred to as outer region) 41 side. Thereby, the width of the portion where the tensile stress is most applied when the connecting member 40 is bent can be widened, and the tensile stress can be distributed to two places where the width is narrowed.
In addition, the formation region of the thin portion is a portion excluding both sides in the circumferential direction of the radially inner region (hereinafter also simply referred to as an inner region) 43, that is, a region surrounded by a dotted line.
In order to improve the strength of the central portion in the circumferential direction of the connecting member 45, the connecting member 45 shown in FIG. 4C has the through-hole 31 shown in FIG. A through-hole 46 having a configuration is formed.
In this case, as compared with the connecting member 30 of FIG. 4A, when the connecting member 45 is bent, the compressive stress applied to the central portion in the circumferential direction of the connecting member 45 is increased, and it is easy to bulge in the thickness direction. It is preferable to form a thin portion over the entire direction inner region 47 (hereinafter also simply referred to as an inner region), that is, in a region surrounded by a dotted line.

In the connecting member 50 shown in FIG. 4D, the shape of the through hole 51 is V-shaped. Thereby, the width of the portion to which the compressive stress is most applied in the radially inner region (hereinafter also simply referred to as the inner region) 52 when the connecting member 50 is bent can be reduced, and the radially outer region (hereinafter also simply referred to as the outer region). The width of the portion to which the most tensile stress 53 is applied can be widened.
For this reason, the formation region of the thin portion is a portion excluding both sides in the circumferential direction of the inner region 52, that is, a region surrounded by a dotted line.
In FIGS. 4A to 4D described above, the thin portion is formed only in the inner region. However, as shown in FIG. 3, the whole connecting member may be pressed.

With the above configuration, the inner notch 21 provided in the connecting member 12 can give a good hinge effect to the connecting member 12 when the connecting member 12 is bent.
Further, when the connecting member 12 is bent, the outer peripheral portion of the connecting member 12 is pulled in the circumferential direction, the thickness thereof is reduced, and a radially bulging portion 19 is formed on the radially outer side. Since it is arranged in the notch 20, there is no problem. On the other hand, the inner peripheral portion of the connecting member 12 is compressed in the circumferential direction and tries to bulge in the thickness direction, but the amount of bulge is suppressed by the effect of the through-hole 15 and further the thin-walled portion 28. Is prevented.
In addition, an engaging portion 57 configured by a concave portion 55 and a convex portion 56 fitted to the concave portion 55 is provided in the radially inner region of the side end portion 14 of the adjacent segment core pieces 13. The side end portions 14 of the adjacent segment core pieces 13 including the concave portions 55 and the convex portions 56 are arranged close to each other with a gap therebetween, but may be brought into contact with each other.
Thereby, the mutual positioning of the adjacent segment core pieces 13 can be implemented with higher accuracy, and the annular accuracy can be improved.

As shown in FIG. 1, when winding and laminating a plurality of segment core pieces 13, the connecting members 12 provided between the adjacent segment core pieces 13 are shifted to different positions in the lamination direction, and each pole piece The position of the part 17 is matched. In the present embodiment, when the segment core pieces 13 are stacked, they are shifted in the stacking direction by one slot, but may be shifted by two or more.
Here, when the total number of slots per round of the laminated core in plan view is m and the number of slots per segment core piece (same as the number of magnetic pole pieces) is n, only one slot is required. When the number of segment core pieces per round necessary for shifting in the stacking direction is k, the following relationship is established.
(M + 1) / n = k
Here, m, n, and k are positive integers, respectively, and can be variously changed according to the manufacturing conditions of the laminated core.

In the present embodiment, as shown in FIG. 1, the total number of slots per round of the laminated core in plan view is 20 (m = 20), and the number of magnetic pole pieces per segment core piece is 3 as shown in FIG. The number of segment core pieces required for one turn from the above formula is 7 (k = 7) because the number of slots (corresponding to 3 slots: n = 3), but the magnetic pole of the seventh segment core piece is Only one piece is the next layer when stacked, and the position of the connecting member in the stacking direction is shifted by one pole piece (corresponding to one slot).
Further, when the number of slots shifted in the circumferential direction in the stacking direction is set to two or more, the number of segment core pieces required for one round is changed by changing “1” in the above formula to a shifted number, that is, two or more. Is obtained.
Thus, when the plurality of segment core pieces 13 are wound and stacked, the position of the connecting member 12 is shifted in the stacking direction, so that the coupling strength of the segment core pieces 13 can be further strengthened.

Then, the manufacturing method of the laminated core which concerns on one embodiment of this invention is demonstrated.
First, while conveying the electromagnetic steel sheet (not shown), using one or a plurality of molds (not shown), the plurality of segment core pieces 13 are mutually connected by the connecting member 12 as shown in FIG. A punching process for forming a combined state is performed.
When the segment core pieces 13 are punched, the recess notches 20, the inner notches 21, and the through holes 15 are respectively formed after the slot 16 is normally punched. Depending on the mold shape, the concave notch 20, the inner notch 21, and the through-hole 15 can be formed simultaneously, individually, or by changing the order. It is also possible to carry out with the punching of the slot 16.

In this punching step, the thinned portion 28 may be formed by coining the connecting member at any one time before the formation of the through hole 15, before the formation, or after the formation.
Next, the connecting member 12 is bent starting from the innermost notch 21 of the innermost notch 21, the convex portion 56 is fitted into the concave portion 55 of the adjacent segment core piece 13, and the side end portion 14 of the segment core piece 13 is While aligning, an annular forming step of winding and laminating a plurality of continuous segment core pieces 13 in a spiral manner is performed to produce a laminated core 10.

As described above, the present invention has been described with reference to one embodiment. However, the present invention is not limited to the configuration described in the above embodiment, and is described in the claims. Other embodiments and modifications conceivable within the scope of the above are also included. For example, the case where the laminated core of the present invention and the manufacturing method thereof are configured by combining some or all of the above-described embodiments and modifications are also included in the scope of the right of the present invention.
Moreover, in the said embodiment, although the case where the laminated iron core was a stator laminated iron core was demonstrated, of course, a rotor laminated iron core (it is also called a rotor) may be sufficient. In this case, the rotor laminated core is composed of a plurality of segment core pieces, and the adjacent segment core pieces are coupled to each other by connecting members formed on the outer peripheral portion. Here, for example, when the connecting member is likely to be cut during the transportation of the plurality of segment core pieces, a rib may be provided on the inner peripheral portion thereof in order to further join the adjacent segment core pieces. This rib may be cut off when the laminated core is manufactured.

It is a top view of the laminated iron core which concerns on one embodiment of this invention. It is a fragmentary top view which shows the state before lamination | stacking of the segment core piece of the same laminated iron core. It is explanatory drawing of the formation method of the thin part of the connection member of the same laminated iron core. (A)-(D) are the partial top views of the connection member which concerns on a modification, respectively.

Explanation of symbols

10: laminated iron core, 11: outer periphery, 12: connecting member, 13: segment core piece, 14: side end, 15: through hole, 16: slot, 17: magnetic pole piece, 18: yoke piece, 19: Radial bulge part, 20: recessed notch, 21: inner notch, 22: innermost part, 23: radially inner area, 24: radially outer area, 25: punch, 26, 27: crush margin, 28 : Thin part, 30: Connecting member, 31: Through hole, 32: Radial inner region, 33, 34: Inner peripheral edge, 35: Radial outer region, 36, 37: Outer peripheral member, 40: Connecting member, 41: Radius Direction outer region, 42: Through hole, 43: Radial inner region, 45: Connecting member, 46: Through hole, 47: Radial inner region, 50: Connecting member, 51: Through hole, 52: Radial inner region, 53: radially outer region, 55: recessed portion, 56: Part, 57: engaging portion

Claims (6)

In the laminated core in which the side end portions of the adjacent segment core pieces connected to each other by the connecting members are folded and joined together while bending the connecting members, and the plurality of continuous segment core pieces are spirally wound and laminated.
The connecting member is formed so as to connect the outer peripheral portions of the adjacent segment core pieces, and a radially bulging portion formed on the radially outer side when the connecting member is bent is formed on the radially outer side of the connecting member. A recess notch that fits in the outer circle of the laminated core is provided, and on the radially inner side, an inner notch that forms a bending position of the connecting member is provided,
The connecting member is provided with a through hole that divides the connecting member into a radially outer region and a radially inner region, and suppresses a swelling in the thickness direction that occurs when the connecting member is bent,
In addition, a radial width W1 of the radially inner region formed on the connecting member radially inward with the through hole as a center, and the connecting member formed on the radially outer side with the through hole as a center. The laminated core according to claim 1, wherein a radial width W2 of the radially outer region is 10% or more and 40% or less of a radial width of the connecting member . 2. The laminated iron core according to claim 1, wherein one or two of the width W <b> 1 of the radially inner region and the width W <b> 2 of the radially outer region of the connecting member formed by the through holes are the same in the circumferential direction. A laminated iron core characterized by its width. The laminated core according to claim 2, wherein a width W1 of a radially inner region of the connecting member is narrower than a width W2 of a radially outer region of the connecting member. The laminated core of any one of Claims 1-3 WHEREIN: The side edge part of the adjacent said segment core piece is comprised by the recessed part and the convex part fitted to this, and the said adjacent segment core pieces are the same. A laminated iron core characterized in that an engaging portion for positioning is provided. 5. The laminated core according to claim 1, wherein the side end portions of the adjacent segment core pieces are arranged close to each other with a gap. A plurality of continuous segments while forming a plurality of segment core pieces in a state of being connected to each other by a connecting member and a side end portion of the adjacent segment core pieces by bending the connecting member In the manufacturing method of the laminated core having an annular forming step of winding and laminating the core pieces in a spiral manner,
The connecting member is formed so as to connect outer peripheral portions of the adjacent segment core pieces, and in the punching step , the connecting member is divided into a radially outer region and a radially inner region, A through-hole that suppresses swelling in the thickness direction that occurs when the connecting member is bent is formed, and the radial width of the radially inner region that is formed radially inward of the connecting member around the through-hole W1 and a radial width W2 of the radially outer region formed radially outside the through hole in the connecting member are 10% or more and 40% or less of the radial width of the connecting member, respectively. A method for producing a laminated iron core, comprising:

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