JP6998264B2 - Manufacturing method of laminated iron core and laminated iron core - Google Patents

Description

The present invention relates to a laminated iron core having an insulating layer formed in a slot and a method for manufacturing the laminated iron core.

The stator core (laminated core) insulates the coil wound around the magnetic pole portion by filling the slots with resin and forming an insulating layer around the magnetic pole portions formed by the adjacent slots.
For example, Patent Document 1 discloses a technique in which the entire stator core is covered with a resin molding die, and an insulating layer made of resin is formed not only on the magnetic pole portion but also on the entire surface of the stator core. However, when the insulating layer is formed on the entire stator core, the amount of resin used is large, which is uneconomical.
Therefore, as in Patent Document 2, the stator core is placed in the molding die, and the resin is injected into the molding die to partially form an insulating layer (bobbin) only around the magnetic pole portion. Technology has been proposed.

Japanese Unexamined Patent Publication No. 61-293136 Japanese Unexamined Patent Publication No. 2006-21182

Generally, a plurality of core pieces constituting the stator core are punched and formed by a press die, but the punched core pieces tend to be elliptical instead of a perfect circle (tendency to be elliptical). It is known.
For this reason, when the insulating layer is partially formed, resin leakage occurs on the outer circumference of the stator core due to the difference in dimensional accuracy between the mold used to form the insulating layer and the stator core, resulting in product quality. There was a risk of causing a decline in. In particular, since the slots are open in the stacking direction and the radial direction, resin leakage from the opened portions is remarkable.

The present invention has been made in view of such circumstances, and provides a method for manufacturing a laminated core and a laminated core capable of preventing resin leakage when filling a slot with resin without being affected by the dimensional accuracy of the laminated core. The purpose is.

The laminated iron core according to the first invention has an annular yoke portion, a plurality of magnetic pole portions connected to the inner peripheral side of the yoke portion, and a slot arranged between the magnetic pole portions adjacent to each other in the circumferential direction. In the laminated iron core to prepare
An insulating layer made of a single member integrally molded with resin is provided on a proximal end surface, a radial opening, and a side surface of the magnetic pole portion in the slot, and the insulating layer formed in each slot is viewed in a plan view. It is annular and the radial opening is closed by the insulating layer.
The thickness of the insulating layer formed on the side surface of the magnetic pole portion is gradually reduced or thickened in the laminating direction of the laminated iron core .

In the laminated iron core according to the first invention, it is preferable to provide an insulating layer on the upper surface or the lower surface of the magnetic pole portion.

Further, in the laminated iron core according to the first invention, it is preferable that the corner portion of the insulating layer formed on the upper surface or the lower surface of the magnetic pole portion has an R shape or is chamfered.

In the method for manufacturing a laminated iron core according to the second invention, resin is filled in the peripheral wall portion of a slot of a laminated iron core in which a plurality of core pieces are laminated, and an insulating layer is formed around a magnetic pole portion formed by adjacent slots. In the method of manufacturing a laminated iron core, a core member is placed in the slot, resin is injected between the peripheral wall portion of the slot and the core member, and the base end surface, the radial opening, and the magnetic pole portion of the slot are formed. The step of integrally molding an insulating layer made of a single member on the side surface is included, the insulating layer formed in each slot is annular in a plan view, and the radial opening is closed by the insulating layer.

In the method for manufacturing a laminated iron core according to the second invention, it is preferable to bring the closing member into contact with the radial opening of the slot and inject the resin into the slot.

In the resin sealing method for the laminated core according to the present invention, the plates are brought into contact with both end faces in the stacking direction of the laminated core, and the closing member is brought into contact with one end surface in the radial direction of the laminated core to form an open portion of the slot. When it is blocked, it is possible to prevent the resin injected into the slot from leaking out.
In particular, when the closing member can be expanded and contracted in the radial direction of the laminated iron core, it is possible to prevent leakage of the resin injected into the slot without being affected by the dimensional accuracy of the laminated iron core.

Here, since the core member is arranged in the slot, the amount of resin to be injected into the slot can be reduced, and it is not necessary to remove the resin by machining in order to secure the winding area. Further, since the core member can suppress the outflow of the resin to the open portion of the slot, it is possible to prevent the resin from leaking out.
When the gap between the inner surface of the opening of the plate and the side surface of the core member is 10 μm or less, the resin does not enter the gap, so that the resin can be reliably injected into the slot of the laminated iron core.

Further, when the resin flow path is formed in the plate, for example, the resin can be reliably injected between the core member and the magnetic pole portion.

When the opening of the plate is formed larger than the slot in a plan view corresponding to the formation range of the insulating layer, the injection of the resin into the opening of the plate is applied to a part of the opening of the plate. The notch provided is used as a starting point.
Since the resin remaining in the mold into which the resin is injected and the resin remaining in the opening of the plate (that is, adhering to the magnetic pole portion) are cured together, the mold is laminated after the resin is cured. When the mold is released from the mold, the resin (that is, the insulating layer) cured at the opening of the plate is liable to crack. Therefore, by injecting the resin into the opening of the plate from the notch provided in the opening of the plate, the resin cured in the notch is positively cracked and cured within the forming range of the insulating layer. By suppressing and further preventing cracking of the resin, it is possible to manufacture a laminated iron core of good quality (good insulation).

Then, when the radial ends of the slot portions forming the adjacent magnetic pole pieces are closed for the iron core pieces at both ends in the stacking direction of the laminated iron core, the closed portion and the plate can be overlapped with each other in a plan view. Also, for the core pieces of the laminated core, if the opening at the radial end of the slot that forms the adjacent magnetic pole pieces is closed by a removable connection, then this connection and the plate, It can be viewed in a plan view and overlapped. As a result, it is possible to reliably prevent the resin to be injected into the slot from leaking without being affected by the dimensional accuracy of the laminated iron core (in particular, it is possible to prevent the resin from leaking from the open portion in the stacking direction of the slot).
Further, when the above-mentioned connecting portion is used, the radial end portion of all the slot portions can be opened by removing the connecting portion from the iron core piece after curing the resin injected into the slot, so that the motor characteristics are deteriorated. Can be prevented.

When the end face located on the slot tip side of the plate is located on the base side of the end face on the tip end side of the slot of the iron core piece in a plan view, when the closing member is brought into contact with the radial end surface of the laminated iron core. , It is possible to prevent the closing member from coming into contact with the end face of the plate. Therefore, since the closing member can be reliably brought into contact with one end surface in the radial direction of the laminated iron core, leakage of the resin from the radial opening portion of the slot can be reliably prevented.

Further, when the contact portion of the closing member with the laminated iron core is made of an elastic member, for example, even if the dimensions of the laminated iron core vary, the variation can be absorbed by the deformation of the elastic member, so that the resin leaks reliably. Can be prevented.

Further, when the positioning member is arranged on the other end surface side in the radial direction of the laminated iron core before the resin is injected into the slot, the laminated iron core can be sandwiched from both sides in the radial direction by the positioning member and the closing member.
When the resin is injected into the slot, the laminated iron core is affected by stress from the inside to the outside (or from the outside to the inside) in the radial direction by the closing member, and is easily deformed. Therefore, by arranging the positioning member on the other end surface side in the radial direction of the laminated iron core, it is possible to exert a counterforce even if the laminated iron core is affected by stress by the closing member. As a result, deformation of the laminated iron core can be suppressed and further prevented, so that, for example, leakage of resin from the front side of the magnetic pole portion (between adjacent magnetic pole pieces) can be suppressed and further prevented.

(A) is an explanatory view of a resin sealing method of a laminated iron core according to an embodiment of the present invention, (B) is a partially enlarged plan view showing a resin sealing method of the laminated iron core, and (C) is a modified example 1. It is a partially enlarged plan view which shows the stacking direction closing process which concerns on. It is a partial perspective view which shows the stacking direction closing process of the resin sealing method of the laminated iron core. It is a partial plan view which shows the radial closing process of the resin sealing method of the laminated iron core. (A) is a partially enlarged plan view of FIG. 3, and (B) is a cross-sectional view taken along the line aa of FIG. It is explanatory drawing of the laminated iron core which concerns on modification 2. It is a top view of the laminated iron core. (A) is a partially enlarged plan view showing a stacking direction closing step according to Modification 3, and (B) is a cross-sectional view taken along the line bb of (A). (A) is an explanatory diagram showing a radial closing step of the resin sealing method of the laminated iron core according to the embodiment of the present invention, and (B) and (C) are radial closing steps according to Modifications 4 and 5, respectively. It is explanatory drawing which shows. (A) to (C) are explanatory views which show the radial closing process which concerns on modification 6-8 respectively.

Subsequently, an embodiment embodying the present invention will be described with reference to the attached drawings, and the present invention will be understood.
First, the laminated iron core 10 manufactured by using the resin sealing method of the laminated iron core according to the embodiment of the present invention will be described with reference to FIGS. 1 to 3.

The laminated core 10 is a stator core (stator).
The laminated iron core 10 is formed by laminating a plurality of annular iron core pieces 11 and 12.
As shown in FIGS. 1A and 1B, the iron core pieces 11 are located at both ends of the laminated iron core 10 in the stacking direction, and the radial end portions of the slot portions forming the adjacent magnetic pole pieces are formed. Inner end) is closed. Further, the (other) iron core piece 12 other than the iron core piece 11 is located in a region (central portion in the stacking direction) excluding both ends in the stacking direction of the laminated iron core 10, and is a slot forming adjacent magnetic pole pieces. The radial end (inner end) of the portion is an opening (opening).

The above-mentioned iron core pieces 11 and 12 have an annular integrated structure, but may have a divided structure capable of connecting a plurality of arcuate iron core pieces in an annular shape. The iron core piece 12 may have a structure in which a part of a plurality of arcuate iron core pieces in the circumferential direction is connected by a connecting portion and the connecting portion can be bent to form an annular shape.
Further, the laminated core may be formed by sequentially rolling a plurality of block cores formed by laminating a plurality of annular core pieces (in FIGS. 2 to 4, this form of the laminated core). Is illustrated). The plurality of block cores all have the same shape, but for example, some block cores may have different shapes.

The iron core pieces 11 and 12 are formed by punching from a strip (thin plate strip) made of an electromagnetic steel sheet or amorphous steel having a thickness of, for example, about 0.10 to 0.5 mm. The iron core pieces 11 and 12 may be punched out from one strip, or may be punched in a state where a plurality of strips (for example, two or even three or more) are stacked.
Here, the iron core piece 11 is formed with a connecting portion 13 that connects the radial end portions (tip portions) of the adjacent magnetic pole pieces without punching out the radial end portion of the slot portion. The width of the connecting portion 13 in the radial direction is, for example, about 0.5 to 5 mm, although it depends on the type and size of the laminated iron core 10.
Further, in the iron core piece 12, the radial end portion of the slot portion is punched out, and a gap is formed at the radial end portion (tip portion) of the adjacent magnetic pole pieces.

In the laminated iron core 10, the iron core pieces 11 and 12 adjacent to each other in the laminating direction and the iron core pieces 12 and 12 are connected by caulking, but the caulking, resin (thermosetting resin (for example, epoxy resin) or thermoplastic) It can also be connected using any one or more of resin), an adhesive, and welding.
The number of the above-mentioned iron core pieces 11 is preferably one on one side in the stacking direction, for example, but may be a plurality of pieces (for example, about two or three pieces).

The laminated iron core 10 has an annular yoke portion 14 and a plurality of magnetic pole portions 15 integrally connected to the inner peripheral side of the yoke portion 14. The magnetic pole portions 15 adjacent to each other in the circumferential direction are formed by slots 16 adjacent to each other in the circumferential direction.
The yoke portion 14 and the magnetic pole portion 15 are formed by stacking a plurality of iron core pieces 11 and 12 having a yoke piece portion and a magnetic pole piece portion, respectively. The magnetic pole piece portion is formed by punching a slot portion with respect to the strip, and the slot 16 is formed by laminating the magnetic pole piece portion.

Therefore, in the slot 16, the radial ends of both ends of the laminated core 10 in the stacking direction are closed by the connecting portion 13, and the radial ends of the region excluding both ends of the laminated core 10 in the stacking direction extend in the stacking direction. It is open. As a result, the slot 16 has a stacking direction opening 17 opened on both sides in the stacking direction and a radial opening 18 opened in the radial direction.
Further, an insulating layer is formed around the magnetic pole portion 15 (that is, the upper surface, the lower surface, both side surfaces, and the proximal end surface (the proximal end surface of the slot 16)). This insulating layer is formed by filling the peripheral wall portion of the slot 16 with a resin 19 having the same component or a different component as the above-mentioned resin (resin used for connecting adjacent iron core pieces in the stacking direction) and curing the resin. Will be done.
Reference numerals 20 shown in FIGS. 2 and 3 are bolt holes used when bolting the laminated iron core 10, and are provided so as to project outward in the radial direction of the yoke portion 14 and have an interval in the circumferential direction. It is formed on the bolt ear 20a. The number of the bolt holes 20 is 3, but it can be variously changed depending on the type of the laminated iron core 10, and may be, for example, 0 or a plurality of 2 or more.

As described above, in the laminated iron core 10, the iron core piece 11 in which the radial end portion of the slot portion forming the adjacent magnetic pole piece portion is closed and the radial end portion of the slot portion forming the adjacent magnetic pole piece portion are open. Although it is formed by laminating the iron core pieces 12 as the portions, the laminated iron core may be formed by laminating only a plurality of iron core pieces 12.
In this case, the radial end of the laminated iron core opens in the laminated direction.

Further, the laminated iron core 10a according to the modified example 2 will be described with reference to FIGS. 5 and 6, but since the laminated iron core 10a has substantially the same configuration as the above-mentioned laminated iron core 10, the reference numeral is “a”. Is added, and detailed explanation is omitted.
The laminated iron core 10a is a stator core (stator), and is formed by laminating a plurality of annular iron core pieces 11a.
Each iron core piece 11a forms adjacent magnetic pole pieces by an annular (ring-shaped) scrap portion (an example of a connecting portion) 13a formed at the tips (inside in the radial direction) of a plurality of magnetic pole pieces arranged in an annular shape. The opening at the radial end of the slot is closed.

The scrap portion 13a becomes a laminated scrap body 21 by laminating a plurality of iron core pieces 11a. It is also possible to form a caulking in each scrap part and connect a plurality of scrap parts to form a laminated scrap body, or to divide each scrap part into a plurality of pieces in the circumferential direction to form a laminated scrap body in the circumferential direction. It can also be divided into.
As a result, in the slot 16a, the radial opening 18a that opens in the radial direction is closed by the laminated scrap body 21.

The laminated scrap body 21 is removed from the tip of the magnetic pole portion (removable) in order to open the radial end portion (radial opening portion 18a) of the slot 16a after forming an insulating layer around the magnetic pole portion 15a. It has become).
Therefore, when the iron core piece 11a is punched out from the strip, it is preferable to form the scrap portion 13a by pushback and keep it in a state of being separated from the tip of each magnetic pole piece portion. That is, the scrap portion 13a is once separated from the tip of each magnetic pole piece portion of the iron core piece 11a, and then fitted again.

Subsequently, the resin sealing method of the laminated iron core according to the embodiment of the present invention will be described with reference to FIGS. 1 to 4.
In the resin sealing method of the laminated iron core, a plurality of iron core pieces 11 and 12 punched out from the strip using a die (not shown) are laminated to form the laminated iron core 10, and then the peripheral wall portions of the plurality of slots 16 are formed. Is filled with resin 19 and cured to form an insulating layer around the magnetic pole portion 15 (here, the upper surface, the lower surface, both side surfaces, and the proximal end surface (base end surface of the slot 16) of the magnetic pole portion 15). It has a laminated iron core manufacturing process, a laminating direction closing step, a radial closing step, and a resin filling step. Hereinafter, it will be described in detail.

(Laminate iron core manufacturing process)
A plurality of iron core pieces 11 and 12 punched out from a strip using a die are sequentially laminated to manufacture a laminated iron core 10.
The laminated iron core 10 has an annular yoke portion 14 and a plurality of magnetic pole portions 15 integrally connected to the inner peripheral side of the yoke portion 14, and the magnetic pole portions 15 are adjacent slots 16 in the circumferential direction. Is formed by. At this point, the above-mentioned insulating layer is not formed around the magnetic pole portion 15.

When punching the iron core pieces 11 and 12 from the strip, in the case of the iron core pieces 11 located at both ends of the laminated iron core 10 in the stacking direction, the tips of the adjacent magnetic pole pieces are connected (connecting portion 13). (The tip of the slot portion is closed), and in the case of the other iron core pieces 12, a gap is formed at the tips of the adjacent magnetic pole pieces (the tip of the slot portion is opened).
The connecting portion 13 may be formed by pushback. That is, both ends of the connecting portion 13 may be once separated from the iron core piece 11 and then fitted into the iron core piece 11.
As a result, as shown in FIG. 1A, in the slot 16, the tips of both ends of the laminated iron core 10 in the stacking direction are closed by the connecting portion 13, and the above-mentioned laminated direction opening 17 and the radial opening 18 are closed. It has a shape to have.

(Laminating direction closing process)
As shown in FIGS. 1A and 2, the upper plate 24 and the lower plate 25 are brought into contact with the upper surface 22 and the lower surface 23, which are both end faces in the stacking direction of the laminated iron core 10, respectively, and the slot 16 is opened in the stacking direction. The portion 17 (here, the portion excluding the contact region with the core member 28 described later) is closed. Note that FIG. 2 shows a state in which a part of the upper plate 24 is partially in contact with the upper surface 22 of the laminated iron core 10 for convenience of explanation, but in reality, the upper plate 24 is annular and the laminated iron core is formed. The upper surface 22 of 10 is covered (the same applies to FIG. 3). Further, the lower plate 25 is also annular like the upper plate 24, but is not shown in FIG. 2 for convenience of explanation (the same applies to FIG. 3).

The upper and lower plates 24 and 25 are installed in a range overlapping the opening in the stacking direction 17 in a plan view. Specifically, as shown in FIGS. 1 (A) and 1 (B), the inner peripheral surface (the end surface located on the slot tip side) of the annular upper plate 24 has a magnetic pole portion 15 in a plan view. It is installed so as to be located on the base side of the magnetic pole portion 15 from the tip of the (slot 16) and on the connecting portion 13 (the same applies to the lower plate 25). Further, the upper plate 24 may cover at least the opening in the stacking direction, and here, the yoke portion 14 is also covered.
The inner peripheral surface of the upper plate 24 (the same applies to the lower plate 25) has a perfect circular shape in FIG. 1 (B), but is not limited to this, and is not limited to this, for example, FIG. 1 (C). Like the upper plate 26 shown in the above, it may have a wavy shape or a polygonal shape.

In this way, the laminated iron core 10 constrained in the laminating direction by the upper and lower plates 24 and 25 is arranged on the base plate 27.
As shown in FIGS. 1A, 2, 3 and 4B, a plurality of core members 28 arranged in each slot 16 are vertically arranged on the base plate 27 in the circumferential direction. ing. In FIGS. 2 and 3, for convenience of explanation, a state in which the core member 28 is arranged only in a part of the slots 16 is shown, but in reality, the core member 28 is arranged in all the slots 16. To.
Further, as shown in FIGS. 2 and 3, a plurality of positioning rods 28a (three in this case) that can be inserted into the plurality of bolt holes 20 stand at intervals in the circumferential direction on the base plate 27. It is installed.

The core member and the positioning rod may be provided on either of the upper and lower plates without being provided on the base plate.
Further, the core member may have a tapered shape (inclination angle: for example, 1 degree or less, further 0.5 degree or less) narrow or wide in the longitudinal direction (stacking direction). This facilitates the insertion of the core member into the slot and the removal of the core member performed after the resin filling step described later. At this time, the thickness of the insulating layer (resin) formed on both side surfaces of the magnetic pole portion gradually becomes thinner or thicker in the laminating direction of the laminated iron core, following the core member. Therefore, when winding the coil around the magnetic pole portion, by inserting the coil into the slot from the side where the thickness of the insulating layer is thin (the one having the wider opening width of the slot), there is an advantage that the coil can be easily inserted.

The upper end of the core member 28 is located at a position higher than the total height of the upper and lower plates 24 and 25 and the laminated iron core 10 (the same applies to the positioning rod 28a), and the peripheral side surface thereof is the inner peripheral surface of the slot 16 (slot peripheral wall). ) Has a small gap. The width of this gap can be variously changed according to the thickness of the insulating layer to be formed. Further, by moving the arrangement position of the core member 28 toward the radial opening 18 side of the slot 16, it is possible to further suppress the resin leakage in the resin filling step described later.
Therefore, by placing the laminated iron core 10 restrained by the upper and lower plates 24 and 25 on the base plate 27, the core member 28 has an opening formed in the upper plate 24 as shown in FIG. 4 (B). The laminated iron core 10 is penetrated in the laminated direction through the portion 29 and the opening 30 formed in the lower plate 25, and the tip portion (upper portion) thereof protrudes above the upper plate 24.

Next, the mold mold 31 (upper mold) is placed on the upper surface of the upper plate 24 of the laminated iron core 10 arranged on the base plate 27.
As shown in FIGS. 1A and 4B, the mold 31 has a resin reservoir 32 for accommodating the resin 19 and a plunger 33 for injecting the resin 19 in the resin reservoir 32 into the slot 16. And have.
Further, as shown in FIG. 4B, the mold 31 has a plurality of positioning recesses 34 into which the tip portion of the core member 28 can be fitted, depending on the number of the core member 28 (slot 16). It is formed (the same applies to the positioning rod 28a).

As a result, the core member 28 can be positioned in the slot 16, so that the resin 19 in the resin reservoir pot 32 is placed in the slot 16 via the resin flow path 35 formed in the upper plate 24 (one plate). At the time of injection, it is possible to prevent the position of the core member 28 from being displaced due to the pressure at the time of injection. It is preferable to form a resin flow path also on the lower plate.
The size of the openings 29, 30 formed in the upper and lower plates 24, 25 is smaller than the size of the slot 16 in a plan view, the core member 28 can be inserted, and the resin 19 is injected into the slot 16. The resin 19 can be prevented from leaking from the gap between the side surface of the core member 28 and the inner surfaces of the openings 29 and 30, and can be set within a range that can be prevented. The size of this gap depends on the filler diameter of the resin 19, but is preferably 10 μm or less (further, 5 μm or less), for example.

Further, a recess (engraving) 36 is formed in the upper plate 24, and by placing the mold 31 on the upper plate 24, a resin flow path 35 for guiding the resin 19 to the slot 16 is formed. .. In FIGS. 2, 3, and 4 (A), the resin flow path 35 is shown in large size for convenience of explanation, but the resin flow path 35 is actually small because it corresponds to each slot 16.
As shown in FIG. 4A, the resin inflow port of the resin flow path 35 is provided in a plurality of (here, 5 places) around the core member 28 in a plan view, whereby the core member 28 is provided. The resin 19 can be injected evenly (evenly) through the gap between the side surface and the inner surface of the openings 29 and 30. The upper and lower plates 24 and 25 described above are not particularly limited as long as they can close the opening in the stacking direction of the slot 16 (here, the region excluding the core member 28), and are not particularly limited. It is also possible to use a dummy plate punched from a strip material for punching the iron core pieces 11 and 12.

Further, instead of the upper plate 24 described above, the upper plate 24a shown on the right side of the center line (dashed line) in FIG. 7A can be used to close the stacking direction opening 17 of the slot 16 (lower plate). The same applies). The upper plate 24b, which is a comparative example, is shown on the left side of the center line in FIG. 7 (A) (the same applies to FIG. 7 (B)).
The upper plates 24a and 24b are formed with openings 29a and 29b, respectively, and the sizes of the openings 29a and 29b are set to the insulating layers 36a and 36b formed on the upper surface 22 of the magnetic pole portion 15 shown in FIG. 7B. As shown in FIG. 7 (A), it is made larger than the slot 16 (outline of the magnetic pole portion 15) in a plan view (the same applies to the lower plate).

In this case, a part of the resin injection ports 31a and 31b formed in the mold mold for injecting the resin (having substantially the same configuration as the mold mold 31) overlaps the openings 29a and 29b in a plan view, respectively. (The shaded area in FIG. 7A).
At this time, the resin remaining in the mold-type resin injection ports 31a and 31b and the resin remaining in the openings 29a and 29b of the upper plates 24a and 24b are cured together, so that FIG. 7 (A) shows. The comparative example shown on the left side of (B) has the following problems.
When the mold is released from the laminated iron core after the resin is cured, the formed insulating layer 36b (particularly, sharp corners) is likely to be chipped or cracked (partially enlarged view on the left side of FIG. 7B). The shaded area). Therefore, the thickness of the insulating layer 36b is reduced, and the required insulating distance cannot be secured between the magnetic pole portion 15 and the coil wound around the magnetic pole portion 15, which may lead to poor insulation.

Therefore, as a countermeasure against the above-mentioned problem, as shown on the right side of FIGS. 7A and 7B, a concave notch 30a is provided in a part of the inner peripheral side of the opening 29a of the upper plate 24a. Using the notch 30a as a base point (from the overlapping portion of the resin injection port 31a and the notch 30a), the resin is injected into the opening 29a of the upper plate 24a.
Here, the position where the cutout portion 30a is formed is the radial center portion of the opening portion 29a, but the present invention is not particularly limited as long as the resin can be injected into the opening portion, and may be, for example, a radial end portion. Further, the shape of the notch portion 30a is concave, but the shape is not limited to this, and for example, the contour shape inside the notch portion 30a is made into an arc shape, an elliptical arc shape, a U shape, a V shape, or the like. You can also do it.

As a result, the length of the insulating layer 36a formed on the upper surface 22 of the magnetic pole portion 15 in the circumferential direction can be made longer than the length of the insulating layer 36b which is a comparative example. Therefore, the resin cured at the notch 30a, which has little effect on the insulating property, is positively cracked and cured in the region where insulation is required (corresponding to the formation range of the insulating layer 36b). Since cracking of the resin (shaded portion in the enlarged view on the left side of FIG. 7B) can be suppressed and further prevented, a laminated iron core having good insulating properties can be manufactured.
As shown on the right side of FIG. 7B, the occurrence of cracks in the resin can be suppressed by forming the corners of the insulating layer 36a into an R shape or chamfering the corners. In this case, it is preferable to process the mold or the like according to the shape of the insulating layer to be formed.

(Radical closing process)
As shown in FIGS. 1A, 1B, and 3B, the closing member 38 abuts on the inner peripheral surface (an example of one end surface in the radial direction) 37 of the laminated iron core 10 formed on the tip surface of the magnetic pole portion 15. And close the radial opening 18 of the slot 16.
As shown in FIGS. 1A and 3A, the closing member 38 has an inverted truncated cone-shaped elevating means 39 and a plurality of expansion / contraction portions 40 provided around the elevating means 39. The elevating means 39 has a guide portion 41 divided into a plurality (here, 6 pieces) in the circumferential direction about the axis, and an expansion / contraction portion 40 is provided on the outside (front side) of each guide portion 41. There is.

A slidable slope 43 is formed at the base end of the expansion / contraction portion 40 along the inclined outer peripheral surface 42 of the guide portion 41, and the tip of the expansion / contraction portion 40 abuts on the inner peripheral surface 37 of the laminated iron core 10. A vertical contact surface 44 is formed to close the radial opening 18 of the slot 16. Further, a slide convex portion (not shown) is provided in the vertical direction on the base side of each expansion / contraction portion 40, and the slide convex portion is slidably attached to the slide groove portion formed in the vertical direction of the guide portion 41. (The mounting points of the slide protrusion and the slide groove may be reversed).
The lower surface of each expansion / contraction portion 40 is located below the lower surface of the elevating means 39 (guide portion 41) in a free state (a state in which the closing member 38 is located above the laminated iron core 10).

As a result, by lowering the elevating means 39, the lower surface of each expansion / contraction portion 40 comes into contact with the upper surface of the base plate 27, and each expansion / contraction portion 40 moves upward along the outer peripheral surface 42 of the guide portion 41 and is viewed in a plan view. Since it moves in the direction of expanding in the radial direction, the contact surface 44 of each expansion / contraction portion 40 can be brought into contact with the inner peripheral surface 37 of the laminated iron core 10. Further, by raising the elevating means 39, each of the expansion / contraction portions 40 moves downward along the outer peripheral surface 42 of the guide portion 41, and at the same time, moves in a direction of contraction in the radial direction in a plan view. The contact surface 44 of the above can be separated from the inner peripheral surface 37 of the laminated iron core 10.
In this way, the closing member 38 can be expanded and contracted in the radial direction of the laminated iron core 10.
The contact portion (contact surface 44) of the closing member 38 with the laminated iron core 10 is preferably made of an elastic member (for example, a fluorine-based resin, a silicon-based resin, a urethane-based resin, or the like).

As described above, when each of the expansion / contraction portions 40 of the closing member 38 is moved in the direction of expanding in the radial direction in a plan view and brought into contact with the inner peripheral surface 37 of the laminated iron core 10, the laminated iron core 10 is closed. The member 38 is affected by stress from the inside to the outside in the radial direction.
At this time, as shown in FIGS. 2, 3, and 8 (A), the laminated iron core 10 has the positioning rod 28a inserted into the bolt hole 20 and positioned on the base plate 27, so that the positioning rod 28a is arranged. In the region (phase), the counterforce against the stress caused by the closing member 38 acts, and the deformation of the laminated iron core 10 is suppressed or further prevented.
However, in the region (phase) where the influence of the counterforce by the positioning rod 28a is small, the laminated iron core 10 is deformed by the stress of the closing member 38, and the resin is released from the tip side of the magnetic pole portion 15 (between the adjacent magnetic pole pieces). It becomes easy to leak.

Therefore, before injecting the resin 19 into the slot 16, it is preferable to form the forms shown in FIGS. 8 (B), 8 (C), and 9 (A) to 9 (C).
In FIG. 8B, the positioning member 46 of the laminated iron core 10 is arranged on the outer peripheral surface (an example of the other end surface in the radial direction) 45 side of the laminated iron core 10 located on the side opposite to the closing member 38, and the positioning member 46 The laminated iron core 10 is sandwiched between the expansion / contraction portions 40 of the closing member 38 from both sides in the radial direction.
Specifically, the positioning member 46 is composed of a plurality of columnar (here, three) positioning pins 47, and the positioning pins 47 are arranged at equal intervals in the circumferential direction of the laminated iron core 10 with the base plate (base plate 27). It is placed upright in a structure (almost the same configuration).

The positioning pin 47 is located between the positioning rods 28a adjacent to each other in the circumferential direction of the laminated iron core 10, and the three positioning pins 47 and the three positioning rods 28a are centered on the axis of the laminated iron core 10. They are arranged at equal angles. Here, the positioning pin 47 and the positioning rod 28a are arranged at positions facing each of the expansion / contraction portions 40 of the closing member 38.
As a result, the region where the influence of the counterforce by the positioning rod 28a is small can be complemented by the positioning pin 47, so that the deformation of the laminated iron core 10 can be suppressed or further prevented.
Therefore, leakage of the resin from the front side (inner diameter side) of the magnetic pole portion 15 (between the adjacent magnetic pole pieces) can be suppressed and further prevented.

8 (C) shows a V-shaped notch groove 48 formed in a plan view on the outer peripheral surface 45 of the laminated iron core 10 in the above-mentioned FIG. 8 (B), and a positioning pin is formed in the notch groove 48. A part of 47 is brought into contact with the fitting.
By changing the shape of the laminated iron core 10 in this way, the counterforce by the positioning pin 47 can be further increased. In addition, there is an advantage that the positioning accuracy of the laminated iron core 10 is improved.

In FIG. 9A, the positioning pin 47 is further arranged between the positioning rod 28a and the positioning pin 47 adjacent to each other in the circumferential direction of the laminated iron core 10 shown in FIG. 8B. That is, three (plural) positioning pins 47 are arranged between the positioning rods 28a adjacent to each other in the circumferential direction of the laminated iron core 10, and the nine positioning pins 47 and the three positioning rods 28a are placed on the laminated iron core. It is arranged at an equal angle around the axis of 10.
The newly arranged positioning pin 47 (positioning pin 47 not arranged in FIG. 8B) is arranged at a position opposite to the space between the adjacent expansion / contraction portions 40.

FIG. 9B shows an arcuate shape in a plan view, wherein the positioning member 49 arranged on the outer peripheral surface 45 side of the laminated iron core 10 is provided with a contact surface 50 capable of contacting the outer peripheral surface 45 of the laminated iron core 10. It is composed of a plurality of (here, three) positioning blocks 51. The positioning block 51 is erected on a base plate (similar to the base plate 27) so as to be located between bolt ears 20a adjacent to each other in the circumferential direction of the laminated iron core 10 at equal intervals in the circumferential direction of the laminated iron core 10. Although it is arranged, it may be arranged independently of the base plate.
Each positioning block 51 can also be pressed (pressurized) toward the laminated iron core 10 side (axial core side of the laminated iron core 10).

Further, although the above-mentioned laminated iron core 10 is formed with bolt ears 20a, even in the laminated iron core 10b without bolt ears 20a shown in FIG. 9C, the outer peripheral surface of the laminated iron core 10b (the other end surface in the radial direction). Example) A positioning member 53 of the laminated iron core 10b can be arranged on the 52 side, and the laminated iron core 10b can be sandwiched between the positioning member 53 and the closing member 38 from both sides in the radial direction.
The positioning member 53 is composed of a plurality of (here, six) positioning pins 47, and the positioning pins 47 are vertically arranged on the base plate at equal intervals in the circumferential direction of the laminated iron core 10b. The six positioning pins 47 are arranged at equal angles with respect to the axis of the laminated iron core 10b.

(Resin filling process)
As shown in FIGS. 1 (A), 4 (A), and (B), the resin 19 is injected into the upper and lower plates 24 and 25, the core member 28, and the slot 16 which is closed by the closing member 38.
The resin 19 is injected from inside the resin reservoir 32 between the core member 28 and the peripheral wall of the slot via the resin flow path 35 by pushing down the plunger 33 of the mold 31. Next, by curing the resin 19 injected into the slot 16, an insulating layer can be formed on the upper surface, the lower surface, both side surfaces, and the base end surface of the magnetic pole portion 15.
Then, after separating the contact surface 44 of each expansion / contraction portion 40 from the inner peripheral surface 37 of the laminated iron core 10, the upper and lower plates 24 and 25 and the core member 28 are removed from the laminated iron core 10, so that each magnetic pole portion 15 A laminated iron core 10 having an insulating layer formed around the core 10 is obtained.

The resin 19 is injected into the slot 16 having the closed space described above in a state where a constant load is applied to the laminated iron core 10 in the laminating direction by the mold 31. The constant load is, for example, about 5 to 100 kN per one laminated iron core 10.
Here, when the load is less than 5 kN, the laminated core is affected by the stack thickness deviation, so that a gap may occur at the end of the laminated core in the stacking direction due to insufficient load, and resin leakage or unfilling may occur. .. On the other hand, when the load exceeds 100 kN, each iron core piece tries to return to its original state (due to springback) when the applied load is released (when the mold is removed), so that the cured resin cracks. It may occur.

The resin 19 that covers the upper surface and the lower surface of the magnetic pole portion 15 covers both side surfaces of the magnetic pole portion 15 by forming counterbore (engraving) (not shown) on the surfaces of the upper and lower plates 24 and 25 that are in contact with the laminated iron core 10. It is integrally formed with the resin 19, and as a result, an insulating layer is formed around the magnetic pole portion 15.
Here, the depth form of the search may be set arbitrarily.
When it is desired to improve the resin sealing property, it is preferable to form a deep counterbore, and when it is desired to reduce the amount of resin, it is preferable to form a shallow counterbore.
Further, even when the insulating layer is not formed on the upper surface and the lower surface of the magnetic pole portion 15, it is preferable to set a counterbore at a part of the upper surface and the lower surface so as to communicate with both side surfaces of the magnetic pole portion 15. In this case, in addition to reducing the amount of resin, it is possible to prevent the iron core piece 11 from peeling off from the laminated iron core 10.

As described above, when the resin is sealed using the upper and lower plates 24 and 25 and the closing member 38, the use of the laminated iron core 10 (iron core piece 11) prevents the resin 19 to be injected into the slot 16 from leaking out. Desirable from the point of view. After sealing the resin, the connecting portion 13 may be removed by machining, whereby the electrical characteristics can be improved.
However, even in the laminated iron core in which only the above-mentioned iron core pieces 12 are laminated, the effect of preventing leakage is inferior to that of the laminated iron core 10 by performing resin sealing using the upper and lower plates 24 and 25 and the closing member 38. The effect of preventing leakage can be improved as compared with the conventional method.

As for the laminated iron core 10a described above, as shown in FIGS. 5 and 6, the radial opening 18a is closed by the laminated scrap body 21. Therefore, when the resin 19 is injected into the slot 16a in the resin filling step described above, the outflow of the injected resin 19 from the radial opening 18a is blocked by the laminated scrap body 21.
Therefore, in the radial closing step described above, the contact surface 44 of the expansion / contraction portion 40 of the closing member 38 is brought into contact with the inner peripheral surface 37a of the laminated scrap body 21, so that the closing member 38 is injected with the resin 19. It can be used preliminaryly to the extent that the laminated scrap body 21 is not deformed.
After forming an insulating layer around each magnetic pole portion 15a of the laminated iron core 10a and removing the closing member 38, the upper and lower plates 24, 25, and the core member (not shown) from the laminated iron core 10a, The laminated scrap body 21 is removed by shifting the laminated scrap body 21 with respect to the magnetic pole portion 15a in the stacking direction. As a result, the radial opening 18a of the slot 16a opens.

As described above, by applying the resin sealing method of the laminated iron core of the present invention, it is possible to prevent resin leakage when filling the slot with the resin without being affected by the dimensional accuracy of the laminated iron core.

Although the present invention has been described above with reference to the embodiments, the present invention is not limited to the configuration described in the above-described embodiments, and the matters described in the claims. It also includes other embodiments and variations that may be considered within the scope. For example, the case where the resin sealing method for the laminated iron core of the present invention is formed by combining a part or all of the above-described embodiments and modifications thereof is also included in the scope of rights of the present invention.
For example, in the above-described embodiment, after performing the stacking direction closing step of abutting the plates on both end faces in the stacking direction of the laminated core, the radial closing step of contacting the closing member with the radial one end surface of the laminated core is performed. Although the case where this is performed has been described, the stacking direction closing step may be performed after the radial closing step is performed, or the stacking direction closing step and the radial closing step may be performed at the same time. In the above-described embodiment, the closing member used in the radial closing step has a configuration in which a plurality of expansion / contraction portions are synchronously expanded / contracted in the radial direction, but each expansion / contraction portion is individually expanded / contracted in the radial direction. It may be a possible configuration.

Further, in the above-described embodiment, the case where the laminated iron core to be resin-sealed is a stator core has been described, but a rotor core provided with a slot may be used. The laminated iron core is not limited to the slot opened at the inner end portion in the radial direction, and may be opened at the outer end portion in the radial direction.
Then, in the above-described embodiment, the case where the resin is injected only into the slots has been described, but depending on the configuration of the laminated iron core, for example, when a magnet insertion hole is formed or a plurality of iron core pieces are connected. When the connecting hole for the purpose is formed, the resin can be injected into the slot and the resin can be injected (simultaneously injected) into the magnet insertion hole and the connecting hole.

Further, in the above-described embodiment, the case where the resin is injected into the slots at once for the entire laminated iron core has been described. However, for example, the laminated iron core is rotated by a preset angle to each slot. It is also possible to inject the resin sequentially.
The resin can be injected into one slot from one plunger (resin reservoir pot), but by changing the formation position of the resin flow path in various ways, a plurality of resins can be injected from one plunger. You can also go to the slot.
Further, the injection of the resin is not limited to being performed from above the laminated iron core, and may be performed from below.

10, 10a, 10b: Laminated iron core, 11, 11a, 12: Iron core piece, 13: Connecting part, 13a: Scrap part (connecting part), 14, 14a: York part, 15, 15a: Magnetic pole part, 16, 16a: Slots, 17, 17a: Laminated openings, 18, 18a: Radial openings, 19: Resin, 20: Bolt holes, 20a: Bolt ears, 21: Laminated scraps, 22, 22a: Top surface (end face), 23 , 23a: Bottom surface (end face), 24, 24a, 24b: Upper plate, 25: Lower plate, 26: Upper plate, 27: Base plate, 28: Core member, 28a: Positioning rod, 29, 29a, 29b, 30: Opening, 30a: Notch, 31: Mold type, 31a, 31b: Resin inlet, 32: Resin reservoir, 33: Plunger, 34: Positioning recess, 35: Resin flow path, 36: Recess, 36a, 36b: Insulation layer, 37, 37a: Inner peripheral surface (one end surface in the radial direction), 38: Closing member, 39: Elevating means, 40: Expansion / contraction portion, 41: Guide portion, 42: Outer peripheral surface, 43: Slope, 44: Contact surface, 45: outer peripheral surface (radial other end surface), 46: positioning member, 47: positioning pin, 48: notch groove, 49: positioning member, 50: contact surface, 51: positioning block, 52: outer circumference Surface (radial other end surface), 53: Positioning member

Claims (3)

In a laminated iron core including an annular yoke portion, a plurality of magnetic pole portions connected to the inner peripheral side of the yoke portion, and a slot arranged between the magnetic pole portions adjacent to each other in the circumferential direction.
An insulating layer made of a single member integrally molded with resin is provided on a proximal end surface, a radial opening, and a side surface of the magnetic pole portion in the slot, and the insulating layer formed in each slot is viewed in a plan view. It is annular and the radial opening is closed by the insulating layer.
A laminated iron core characterized in that the thickness of the insulating layer formed on the side surface of the magnetic pole portion gradually becomes thinner or thicker in the laminating direction of the laminated iron core. In a method for manufacturing a laminated iron core in which a peripheral wall portion of a slot of a laminated iron core in which a plurality of iron core pieces are laminated is filled with resin and an insulating layer is formed around a magnetic pole portion formed in the adjacent slots.
A core member is arranged in the slot, and resin is injected between the peripheral wall portion of the slot and the core member to form a proximal end surface, a radial opening, and a side surface of the magnetic pole portion in the slot. Including the process of integrally molding an insulating layer made of a single member with resin.
A method for manufacturing a laminated iron core, wherein the insulating layer formed in each of the slots is annular in a plan view, and the radial opening is closed by the insulating layer. The method for manufacturing a laminated iron core according to claim 2 , wherein a closing member is brought into contact with the radial opening of the slot, and resin is injected into the slot.

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