Method for manufacturing iron core products and holding jig for the iron core body

Abstract

To provide a method of manufacturing an iron core product that can compatibly maintain the rigidity of an insert post and improve cooling performance at low cost, and a holding jig for iron core body.SOLUTION: A method of manufacturing an iron core product comprises: inserting an insert post extending upward from a base part of a holding jig into a center hole of an iron core body to hold the iron core body with the holding jig; pressing the iron core body in a height direction of the holding jig together with the holding jig; and supplying molten resin to a resin supply part provided to the iron core body while heating the iron core body together with the holding jig. The insert post is provided with a plurality of cooling holes extending along the height. The plurality of cooling holes are arranged at substantially uniform intervals to be circular on the whole when viewed from the height direction.SELECTED DRAWING: Figure 2

Description

[Technical Field] 【0001】 This disclosure relates to a method for manufacturing an iron core product and a jig for holding the iron core body. [Background technology] 【0002】 Patent Document 1 discloses a method for manufacturing a rotor core by inserting an insertion part (insertion post) protruding from the base of a jig into the central hole of the rotor core, placing the rotor core on the jig, and then injecting resin into the magnet insertion hole of the rotor core. In order to heat-cur the resin injected into the magnet insertion hole, the rotor core and the jig are heated during resin injection. Once the resin injection is complete and the resin has hardened, the jig is separated from the rotor core. [Prior art documents] [Patent Documents] 【0003】 [Patent Document 1] Japanese Patent Publication No. 2021-136756 [Overview of the project] [Problems that the invention aims to solve] 【0004】 During resin injection, the heat generated causes thermal expansion of the insertion part, which may prevent it from being inserted into the central hole of the subsequent rotor core. Therefore, to ensure sufficient cooling of the jig, it may be advisable to install high-capacity cooling equipment on the production line. However, the installation of cooling equipment could increase manufacturing costs. 【0005】 Therefore, this disclosure describes a method for manufacturing an iron core product and a holding jig for the iron core body that can achieve both rigidity maintenance of the insertion post and improved cooling performance at low cost. [Means for solving the problem] 【0006】 One example of a method for manufacturing an iron core product includes inserting an insertion post extending upward from the base of a holding jig into the central hole of the iron core body to hold the iron core body in the holding jig, pressurizing the iron core body together with the holding jig in the height direction of the holding jig, and supplying molten resin to a resin supply section provided in the iron core body while heating the iron core body together with the holding jig. The insertion post is provided with a plurality of cooling holes extending along the height direction. The plurality of cooling holes are arranged at substantially uniform intervals so that they form a circular shape when viewed from the height direction. 【0007】 An example of a core holder includes a base and an insertion post that extends upward from the base and is configured to allow insertion of the central hole of the core. The insertion post is provided with a plurality of cooling holes that extend along the height direction of the insertion post. The plurality of cooling holes are arranged at substantially uniform intervals so that they form a circular shape when viewed from the height direction. [Effects of the Invention] 【0008】 According to the manufacturing method of the core product and the holding jig for the core body described herein, it is possible to achieve both rigidity maintenance of the insertion post and improved cooling performance at a low cost. [Brief explanation of the drawing] 【0009】 [Figure 1] Figure 1(a) is an exploded perspective view showing an example of a rotor laminated core, and Figure 1(b) is a cross-sectional view showing how molten resin is injected into the magnet insertion holes of the laminate by a resin injection device. [Figure 2] Figure 2(a) is a perspective view showing the retaining jig, and Figure 2(b) is a top view (in the direction of extension of the retaining post) showing the retaining jig's insertion post inserted into the central hole of the laminate. [Figure 3] Figure 3 is a flowchart illustrating the manufacturing method of the rotor laminated core. [Figure 4] Figure 4 is a top view showing another example of a through post. [Figure 5]Figure 5(a) shows the range of shear force acting on the insertion post, and Figures 5(b) to (e) show the simulation results when shear force is applied to the insertion post. [Figure 6] Figure 6 shows the simulation results when a shear force is applied to the insertion post. [Modes for carrying out the invention] 【0010】 In the following descriptions, the same reference numeral will be used for identical elements or elements with the same function, and redundant explanations will be omitted. Furthermore, in this specification, when referring to the top, bottom, right, and left of a figure, the direction of the reference numeral in the figure will be used as the reference. 【0011】 [Rotor core configuration] First, the structure of the rotor laminated core 1 (core product) will be described with reference to Figure 1(a). The rotor laminated core 1 comprises a laminated body 2 (core body), a plurality of permanent magnets 3, and a plurality of solidified resins 4. 【0012】 The laminate 2 is cylindrical in shape. Specifically, a central hole 2a is provided in the center of the laminate 2, extending along the central axis Ax and penetrating the laminate 2. The central hole 2a extends in the height direction (up and down direction) of the laminate 2. Since the laminate 2 rotates around the central axis Ax, the central axis Ax is also the axis of rotation. A rotor is formed by inserting a shaft (not shown) through the central hole 2a. An electric motor is formed by combining the rotor with a stator. 【0013】 A pair of protrusions 2b and a plurality of grooves 2c are formed on the inner circumferential surface of the central hole 2a. Both the protrusions 2b and the grooves 2c extend in the height direction from the upper end surface SF1 to the lower end surface SF2 of the laminate 2. The pair of protrusions 2b face each other with respect to the central axis Ax and project from the inner circumferential surface of the central hole 2a toward the central axis Ax. One groove 2c is located on each side of one of the protrusions 2b. 【0014】 The laminate 2 has a plurality of magnet insertion holes 5 (resin supply portions) formed therein. The plurality of magnet insertion holes 5 are arranged at a predetermined interval along the outer peripheral edge of the laminate 2. The magnet insertion holes 5 penetrate the laminate 2 so as to extend along the central axis Ax. That is, the magnet insertion holes 5 extend in the height direction. 【0015】 The shape of the magnet insertion hole 5 may be, for example, a long hole extending along the outer peripheral edge of the laminate 2 when viewed from the height direction. The number of magnet insertion holes 5 may be, for example, six. The position, shape, and number of the magnet insertion holes 5 may be changed according to the application of the motor, the required performance, and the like. 【0016】 The laminate 2 is configured by stacking a plurality of punched members W. The punched member W is a plate-like body obtained by punching a metal thin plate (for example, an electromagnetic steel sheet) into a predetermined shape by a press working device (not shown), and exhibits a shape corresponding to the laminate 2. The laminate 2 may be configured by so-called transfer lamination. "Transfer lamination" means laminating a plurality of punched members W while relatively shifting the angles of the punched members W. Transfer lamination is mainly carried out for the purpose of canceling the plate thickness deviation of the punched members W. The angle of transfer lamination may be set to any size. 【0017】 The adjacent punched members W in the lamination direction may be fastened by caulking portions 6. These punched members W may be fastened by various known methods instead of the caulking portions 6. For example, the plurality of punched members W may be joined to each other using an adhesive or a resin material, or may be joined to each other by welding. Alternatively, temporary caulking may be provided on the punched member W, and after obtaining a laminate by fastening the plurality of punched members W through the temporary caulking, the temporary caulking may be removed from the laminate. Note that "temporary caulking" means caulking used to temporarily integrate a plurality of punched members W and removed in the process of manufacturing the rotor laminated core 1. 【0018】 At least one permanent magnet 3 is inserted into each magnet insertion hole 5. The shape of the permanent magnet 3 is not particularly limited, but may be, for example, a rectangular parallelepiped. The type of permanent magnet 3 can be determined according to the motor's application, required performance, etc., and may be, for example, a sintered magnet or a bonded magnet. 【0019】 The solidified resin 4 is formed when a molten resin material (molten resin) is filled into the magnet insertion hole 5 with the permanent magnet 3 inserted, and then the molten resin solidifies. The solidified resin 4 has the function of fixing the permanent magnet 3 in the magnet insertion hole 5 and the function of joining adjacent punched members W in the height direction. Examples of resin materials that make up the solidified resin 4 include thermosetting resins and thermoplastic resins. Specific examples of thermosetting resins include resin compositions containing epoxy resin, curing initiators, and additives. Examples of additives include fillers, flame retardants, and stress reducing agents. 【0020】 [Configuration of the resin injection device] Next, the configuration of the resin injection device 100 will be described with reference to Figure 1(b). The resin injection device 100 is configured to fill the magnet insertion hole 5 into which the permanent magnet 3 is inserted with molten resin. The resin injection device 100 includes a lower mold 101, an upper mold 102, and a plurality of plungers 103. 【0021】 The lower mold 101 and the upper mold 102 are each rectangular plate-shaped members. The lower mold 101 and the upper mold 102 are configured to clamp and press the laminate 2, which is held by the holding jig 200 (described later), from above and below together with the holding jig 200 (see arrow Ar1 in Figure 1(b)). 【0022】 The upper mold 102 is provided with a central hole 102a, a plurality of accommodating holes 102b, and a heat source 102c. The central hole 102a is located approximately in the center of the upper mold 102 and penetrates the upper mold 102. The central hole 102a has a shape (approximately circular) that corresponds to the insertion post 202 of the holding jig 200 described later, and the insertion post 202 can be inserted through it. 【0023】 Multiple accommodating holes 102b penetrate the upper mold 102 and are arranged at predetermined intervals around the central hole 102a. Each accommodating hole 102b is located at a position corresponding to the magnet insertion hole 5 of the laminate 2 when the lower mold 101 and upper mold 102 clamp the laminate 2 and the holding jig 200. Each accommodating hole 102b is substantially circular in shape and is configured to accommodate at least one resin pellet P. 【0024】 The heat source 102c is, for example, a heater built into the upper mold 102. When the heat source 102c is activated, the upper mold 102 is heated, and through the upper mold 102, the laminate 2, the holding jig 200, and the resin pellets P housed in each housing hole 102b are heated. As a result, the resin pellets P melt and turn into molten resin. 【0025】 Multiple plungers 103 are configured to move up and down relative to their corresponding housing holes 102b by a drive source (not shown). When the plungers 103 descend while molten resin is present in the housing holes 102b, the molten resin is pushed out from the bottom of the housing holes 102b and injected into the corresponding magnet insertion holes 5. Subsequently, when the molten resin hardens, the rotor laminated core 1 is formed. 【0026】 [Configuration of the holding jig] Next, the configuration of the holding jig 200 will be explained with reference to Figures 1(b) and 2. The holding jig 200 is a jig for holding the laminate 2 formed by the press working device and transporting it to the resin injection device 100. In the resin injection device 100, resin is injected into the magnet insertion holes 5 of the laminate 2 to form the rotor laminate core 1, and when the rotor laminate core 1 is removed from the holding jig 200, the holding jig 200 is transported back to the press working device to hold another laminate 2. 【0027】 The holding jig 200 includes a base portion 201 and an insertion post 202. The base portion 201 is a rectangular plate-shaped member. The base portion 201 is configured to support the laminate 2. The insertion post 202 is located approximately in the center of the base portion 201 and extends upward from the upper surface of the base portion 201. The insertion post 202 may be attached to the base portion 201 in a way that allows it to be removed, or it may be fixed so that it cannot be removed from the base portion 201, or it may be integrated with the base portion 201. 【0028】 The insertion post 202 has a substantially cylindrical shape and an outer shape corresponding to the central hole 2a of the laminate 2. That is, the insertion post 202 includes a pair of grooves 203 corresponding to a pair of protrusions 2b of the laminate 2. The grooves 203 extend in the height direction (the direction in which the insertion post 202 extends) from the upper end to the lower end of the insertion post 202. The pair of grooves 203 may be located on the outer circumferential surface of the insertion post 202 such that, when viewed from above (in the direction in which the insertion post 202 extends), they are located on a virtual straight line L1 (a first virtual straight line) passing through the center of the insertion post 202. When the central hole 2a of the laminate 2 is inserted through the insertion post 202, the pair of protrusions 2b engage with the corresponding grooves 203. Note that in Figure 2(b), for illustrative purposes, the outer surface of the insertion post 202 and the inner surface of the central hole 2a of the laminate 2 are shown to be separated. However, in reality, the outer surface of the insertion post 202 is in contact with most of the inner surface of the central hole 2a, excluding the groove 2c. 【0029】 The insertion post 202 may be made of a metal having a coefficient of thermal expansion close to the coefficient of thermal expansion (coefficient of linear expansion) of the multiple punched members W that constitute the laminate 2. Here, "close" means a coefficient of thermal expansion of ±3 × 10⁻⁶ of the coefficient of thermal expansion of the metal that constitutes the punched members W. -6 K -1It may also be at such a level. However, this is not the case if the diameters of the central holes 2a of the laminate 2 and the outer diameters of the insertion posts 202 are not equal. Depending on the dimensions of the laminate 2 and the insertion posts 202 during thermal expansion, a material with an appropriate coefficient of thermal expansion may be selected for the insertion posts 202. When the punching member W is made of an electromagnetic steel sheet, the coefficient of thermal expansion of the electromagnetic steel sheet is 13×10 -6 K -1 So, the coefficient of thermal expansion of the metal constituting the insertion posts 202 may be 10×10 -6 K -1 ~16×10 -6 K -1 It may also be at such a level. The insertion posts 202 may be made of, for example, alloy tool steel. The alloy tool steel may be, for example, SKD11. The coefficient of thermal expansion of the alloy tool steel is 11×10 -6 ~13×10 -6 K -1 Since it is at a level close to the coefficient of thermal expansion of the electromagnetic steel sheet, when the insertion posts 202 are made of alloy tool steel, when injecting the molten resin into the magnet insertion holes 5, the insertion posts 202 also thermally expand in accordance with the thermal expansion of the laminate 2. Therefore, it becomes possible to accurately correct the central holes 2a of the laminate 2 by the insertion posts 202. 【0030】 A plurality of cooling holes 204 are provided in the insertion posts 202. The plurality of cooling holes 204 may extend in the height direction from the upper end surface SF1 to the lower end surface SF2 of the insertion posts 202. That is, the plurality of cooling holes 204 may be through holes penetrating the insertion posts 202. In this case, as illustrated in FIG. 1(b), a plurality of cooling holes 205 may be provided in the base portion 201 at positions corresponding to the plurality of cooling holes 204, and the cooling holes 204 and the cooling holes 205 may communicate with each other. Alternatively, the plurality of cooling holes 204 may be bottomed holes (recesses) extending in the height direction. That is, while the upper end of the cooling hole 204 may open at the upper end surface SF1 of the insertion post 202, the lower end of the cooling hole 204 may not reach the lower end surface SF2 of the insertion post 202. 【0031】 The multiple cooling holes 204 are arranged at approximately uniform intervals so that they form a circle when viewed from above. That is, the multiple cooling holes 204 are arranged on a predetermined virtual circle C1 that is concentric with the insertion post 202 when viewed from above. There may be two or more cooling holes 204. In the example in Figure 2, six cooling holes 204 are provided on the insertion post 202 at approximately 60° intervals. In the example in Figure 2, two of the six cooling holes 204 are located on a virtual line L2 (second virtual line) that is perpendicular to the virtual line L1 and passes through the center of the insertion post 202. 【0032】 The multiple cooling holes 204 may, when viewed from above, be located outside a virtual circle C2 with radius r that is concentric with the center of the insertion post 202, as illustrated in Figure 2(b). The radius r may be, for example, half the radius of the insertion post 202, or three-quarters the radius of the insertion post 202. Alternatively, when viewed from above, the straight-line distance d between the multiple cooling holes 204 and the outer surface of the insertion post 202 may be approximately the radius of the cooling holes 204. The straight-line distance d may be, for example, 10 mm or less, 7 mm or less, or 4 mm or less. 【0033】 In the examples shown in Figures 1(b) and 2, when viewed from the height direction, there are no holes in the inner region of the insertion post 202 surrounded by multiple cooling holes 204. In other words, the central part of the insertion post 202 is solid. 【0034】 [Manufacturing method for rotor laminated iron core] Next, the manufacturing method of the rotor laminated core 1 will be described with reference to Figures 1 to 3. First, a press working device punches out thin metal sheets to form punched members W, and then stacks multiple punched members W to form a laminate 2 (see step S1 in Figure 3). Next, the insertion post 202 of the holding jig 200 is inserted into the central hole 2a of the laminate 2, and the laminate 2 is placed on the base portion 201 of the holding jig 200 (see step S2 in Figure 3). 【0035】 Next, the holding jig 200 that holds the laminate 2 is transported to the resin injection device 100 by, for example, a transport device (not shown), and the laminate 2 is clamped together with the holding jig 200 by the lower mold 101 and the upper mold 102 and pressurized (see step S3 in Figure 3). At this time, the load acting on the laminate 2 and the holding jig 200 can be of various sizes depending on the size of the laminate 2, but may be, for example, around 1 to 40 tons. Also, when the laminate 2 is pressurized by the lower mold 101 and the upper mold 102, the heat source 102c is controlled and the pressurization of the laminate 2 is started. 【0036】 In this process, since the punched members W are formed by press working, the shape of each punched member W constituting the laminate 2 is not necessarily constant due to manufacturing tolerances. Therefore, the shear force acting on the insertion post 202 may not be uniform in the height direction and circumferential direction of the insertion post 202 (see arrow Ar2 in Figure 1(b)). 【0037】 Furthermore, when loads are applied to the laminate 2 from above and below, the laminate 2 deforms so that it stretches radially. As a result, the inner surface of the central hole 2a of the laminate 2 is pressed against the insertion post 202, and a shear force acts on the insertion post 202. At this time, since grooves 2c exist on both sides of the protrusion 2b that protrudes from the inner surface of the central hole 2a, this shear force acts on a part of the insertion post 202 (see arrow Ar3 in Figure 2(b)). In other words, the part of the insertion post 202 is the portion of the inner surface of the central hole 2a that is facing the area excluding the protrusion 2b and grooves 2c. 【0038】 Next, resin pellets P are placed into each of the receiving holes 102b. When the resin pellets P are heated by the heat source 102c of the upper mold 102 and become molten, the plunger 103 descends and the molten resin is injected into each of the magnet insertion holes 5 (see step S4 in Figure 3). At this time, the laminate 2 is heated by the heat source 102c to, for example, about 150°C to 180°C. After that, when the molten resin solidifies, solidified resin 4 is formed in the magnet insertion holes 5. This completes the rotor laminate core 1. 【0039】 Next, the rotor laminated core 1 is removed from the holding jig 200 by, for example, a removal device (not shown) (see step S5 in Figure 3). The rotor laminated core 1, separated from the holding jig 200, is then transported to the next process by, for example, a transport device (not shown). Meanwhile, the holding jig 200 is cooled to, for example, room temperature by a cooling device (not shown) (see step S6 in Figure 3). The cooled holding jig 200 is then transported to a press working machine by, for example, a transport device (not shown) (see step S7 in Figure 3). Note that a cooling device may be provided in the transport path of the holding jig 200 to the press working machine, and the holding jig 200 may be cooled during transport. In this way, the cooled holding jig 200 is returned to the press working machine, the subsequent laminate 2 is placed on the holding jig 200, and the above steps are repeated. 【0040】 [Effect] As shown in the above example, since the insertion post 202 is provided with multiple cooling holes 204, the surface area of ​​the insertion post 202 is increased, and heat exchange with the atmosphere is promoted. Therefore, the cooling of the insertion post 202 is promoted without installing high-capacity cooling equipment on the production line. In addition, since the multiple cooling holes 204 are arranged at approximately uniform intervals so that they form a circle overall when viewed from the height direction, when the laminate 2 is pressed together with the holding jig 200 and a shear force acts on the insertion post 202 from the outer surface side of the insertion post 202, the shear force is easily distributed in the multiple cooling holes 204. Therefore, even if the insertion post 202 is provided with multiple cooling holes 204, the rigidity of the insertion post 202 can be maintained compared to when the insertion post 202 is not provided with holes. Thus, it is possible to achieve both the maintenance of the rigidity of the insertion post 202 and the improvement of cooling performance at a low cost. 【0041】 As shown in the above example, the multiple cooling holes 204 can be located in a region outside half the radius of the insertion post 202 in the radial direction of the insertion post 202. In this case, the shear force acting on the insertion post 202 is distributed by the multiple cooling holes 204 near the outer surface of the insertion post 202. Therefore, deformation of the insertion post 202 tends to be suppressed compared to the case where the holes are provided near the center of the insertion post 202. Thus, it becomes possible to achieve even greater rigidity of the insertion post 202. 【0042】 As shown in the above example, when the laminate 2 is pressed together with the holding jig 200, when viewed from the height direction, shear force is less likely to act on the insertion post 202 in a first direction along the virtual straight line L1, and shear force is more likely to act on the insertion post 202 in a second direction along the virtual straight line L2. Therefore, if there is a hole in the inner region of the insertion post 202 surrounded by multiple cooling holes 204, the hole is located in the center of the insertion post 202 and is susceptible to the effects of shear force, so the hole tends to be compressed and deformed in the second direction. In contrast, as shown in the above example, when viewed from the height direction, there is no hole in the inner region of the insertion post 202 surrounded by multiple cooling holes 204. That is, since there is no hole in the center of the insertion post 202, the rigidity of the insertion post 202 is more easily maintained. 【0043】 [Differentiation] The disclosures herein should be considered in all respects to be illustrative and not restrictive. Various omissions, substitutions, and modifications may be made to the above examples without departing from the claims and the gist thereof. 【0044】 (1) The positions of the multiple cooling holes 204 formed in the insertion post 202 can be changed as appropriate. For example, as illustrated in Figure 4(a), the multiple cooling holes 204 may be located near the virtual circle C2. Alternatively, although not shown, they may be located inside the virtual circle C2. 【0045】 (2) As illustrated in Figure 4(b), another cooling hole 205 may be provided in the center of the insertion post 202 (the inner region of the insertion post 202 surrounded by the multiple cooling holes 204 when viewed from the height direction). 【0046】 (3) The number of cooling holes 204 arranged in a circular pattern on the insertion post 202 may be two or more. Figures 4(c) to 4(e) show an example in which four cooling holes 204 are provided on the insertion post 202 at approximately 90° intervals. In this case as well, the cooling holes 204 may be located near the outer surface of the insertion post 202 (see Figure 4(c)), near the virtual circle C2 (see Figure 4(d)), or inside the virtual circle C2 (not shown). Furthermore, there may be no cooling holes in the center of the insertion post 202 (the inner region of the insertion post 202 surrounded by the cooling holes 204 when viewed from the height direction) (see Figures 4(c) and 4(d)), or another cooling hole 205 may be provided (see Figure 4(e)). 【0047】 (4) Regardless of the number of cooling holes 204, the cooling holes 204 may be located on a virtual straight line L2, as illustrated in Figures 2(b), 4(a), and 4(b). On the other hand, regardless of the number of cooling holes 204, the cooling holes 204 may not be located on a virtual straight line L2, as illustrated in Figures 4(c) to 4(e). In the latter case, when a relatively large shear force acts on the insertion post in a second direction along the virtual straight line L2, the cooling holes 204 are less affected by the shear force. As a result, the rigidity of the insertion post 202 is more easily maintained. 【0048】 (5) The shape of the cooling holes 204 when viewed from the height direction may be any shape, such as a circle, an ellipse, a square, or a hexagon. 【0049】 (6) The multiple cooling holes 204 may be arranged in a grid or mesh pattern on the insertion post 202 when viewed from the height direction (not shown). That is, the multiple cooling holes 204 may include groups arranged in a line in a predetermined direction when viewed from the height direction, or multiple such groups may be arranged in a direction perpendicular to the predetermined direction. In this case, the surface area of ​​the insertion post 202 is further increased, making it possible to improve the cooling performance of the insertion post 202. 【0050】 (7) To improve cooling performance, a cylindrical metal (e.g., copper) with a higher thermal conductivity than the insertion post 202 may be inserted into the cooling hole 204. Alternatively, to increase the rigidity of the insertion post 202, a cylindrical metal (e.g., cemented carbide) with a higher rigidity than the insertion post 202 may be inserted into the cooling hole 204. These cylindrical metals may be removable from the cooling hole 204. 【0051】 [Simulation Results] The deformation of the insertion post 202 when a shear force is applied was simulated using a computer, depending on whether or not there is a hole in the insertion post 202. In this simulation, it was assumed that the shear force acts within a 112° range on both the left and right sides of the insertion post 202, as shown in Figure 5(a). The results are shown in Figures 5(b) to (e) and Figure 6. In these figures, darker colors indicate compressive deformation of the insertion post 202, while lighter colors indicate extensional deformation. Although the simulation was performed with the insertion post 202 as cylindrical, similar results can be obtained even when the insertion post 202 has a groove 203. 【0052】 Figure 5(b) shows the simulation results when no hole is formed in the insertion post 202. In this case, it was confirmed that the deformation of the insertion post 202 is relatively small because there is no hole and the rigidity is high. Figure 5(c) shows the simulation results when a hole is formed in the center of the insertion post 202. In this case, it was confirmed that the rigidity of the insertion post 202 is low due to the effect of the hole in the center, so the compressive deformation is very large in the left-right direction where shear force mainly acts on the insertion post 202, and the extensional deformation is very large in the up-down direction. 【0053】 Figure 5(d) shows the simulation results when multiple holes are formed in the insertion post 202, similar to that shown in Figure 4(b). In this case, there is a tendency for large compressive deformation in the left-right direction and large extensional deformation in the up-down direction, but it was confirmed that the amount of deformation is smaller compared to the result in Figure 5(c). Figure 5(e) shows the simulation results when multiple holes are formed in the insertion post 202, similar to that shown in Figure 2(b). In this case, since there are no holes in the center of the insertion post 202, it was confirmed that the amount of deformation is even smaller compared to the result in Figure 5(d). 【0054】 Figure 6(a) shows the simulation results when multiple holes are formed in the insertion post 202, similar to that shown in Figure 4(a). Compared to the case in Figure 5(e), the multiple holes are located closer to the center of the insertion post 202. In this case, it was confirmed that the amount of deformation is larger compared to the result in Figure 5(e). Figure 6(b) shows the simulation results when multiple holes are formed in the insertion post 202, similar to that shown in Figure 4(e). In this case, since the multiple holes, which are arranged to form a circle as a whole, are not located on a virtual straight line that passes through the center of the insertion post and extends in the left-right direction, it was confirmed that the amount of deformation is even smaller compared to the result in Figure 5(d). 【0055】 Figure 6(c) shows the simulation results when multiple holes are formed in the insertion post 202, similar to those shown in Figure 4(c). In this case, since there are no holes in the center of the insertion post 202, it was confirmed that the amount of deformation is even smaller compared to the result in Figure 6(b). 【0056】 [Other examples] Example 1. An example of a manufacturing method for an iron core product includes inserting an insertion post extending upward from the base of a holding jig into the central hole of the iron core body to hold the iron core body in the holding jig, pressurizing the iron core body together with the holding jig in the height direction of the holding jig, and supplying molten resin to a resin supply section provided in the iron core body while heating the iron core body together with the holding jig. The insertion post is provided with a plurality of cooling holes extending along the height direction. The plurality of cooling holes are arranged at approximately uniform intervals so that they form a circle overall when viewed from the height direction. In this case, since the insertion post is provided with a plurality of cooling holes, the surface area of ​​the insertion post is increased, and heat exchange with the atmosphere is promoted. Therefore, the cooling of the insertion post is promoted without installing cooling equipment with high cooling capacity in the manufacturing line. Furthermore, since the multiple cooling holes are arranged at approximately uniform intervals so that they form a circular shape when viewed from the height direction, when the iron core body is pressed together with the holding jig and a shear force acts on the insertion post from the outer surface side of the insertion post, the shear force is easily distributed among the multiple cooling holes. Therefore, even if the insertion post is provided with multiple cooling holes, the rigidity of the insertion post can be maintained compared to when the insertion post is not provided with holes. Thus, it is possible to achieve both the maintenance of the rigidity of the insertion post and the improvement of cooling performance at a low cost. 【0057】 Example 2. In the method of Example 1, the insertion post is provided with a groove extending along the height direction, and the iron core body is provided with a ridge that extends along the direction of extension of the central hole and is configured to fit with the groove. When viewed from the height direction, there does not need to be a hole in the inner region of the insertion post surrounded by multiple cooling holes. In this case, when the iron core body is pressed together with the holding jig, when viewed from the height direction, shear force is less likely to act on the insertion post in a first direction along a first imaginary straight line passing through the center of the insertion post and the groove, and shear force is more likely to act on the insertion post in a second direction along a second imaginary straight line perpendicular to the first imaginary straight line and passing through the center of the insertion post. Therefore, in the case where there is a hole in the inner region of the insertion post surrounded by multiple cooling holes, the hole is located in the center of the insertion post and is susceptible to the effects of shear force, so the hole tends to be compressed and deformed in the second direction. In contrast, according to Example 2, since there is no hole in the center of the insertion post, the rigidity of the insertion post is more easily maintained. 【0058】 Example 3. In the method of Example 2, the multiple cooling holes do not necessarily have to be located on a second virtual line that is perpendicular to the first virtual line passing through the center of the insertion post and the groove, and also passes through the center of the insertion post, when viewed from the height direction. In this case, a large shear force acts on the insertion post in the second direction. Therefore, if the cooling holes are located on the second virtual line, the cooling holes tend to be more susceptible to the effects of the shear force from the second direction. In contrast, according to Example 3, since the cooling holes are not located on the second virtual line, the rigidity of the insertion post is more easily maintained. 【0059】 Example 4. In any of the methods in Examples 1 to 3, the multiple cooling holes may be located in a region outside of half the radius of the insertion post, when viewed from the height direction, in the radial direction of the insertion post. In this case, the shear force acting on the insertion post is distributed by the multiple cooling holes near the outer surface of the insertion post. Therefore, deformation of the insertion post tends to be suppressed compared to the case where the holes are provided near the center of the insertion post. Thus, it becomes possible to achieve even greater rigidity of the insertion post. 【0060】 Example 5. An example of a holding jig for the iron core body comprises a base portion and an insertion post extending upward from the base portion and configured to allow insertion of the central hole of the iron core body. The insertion post is provided with a plurality of cooling holes extending along the height direction of the insertion post. The plurality of cooling holes are arranged at substantially uniform intervals so that they form a circular shape when viewed from the height direction. In this case, the same effects as the method in Example 1 can be obtained. [Explanation of symbols] 【0061】 1... Rotor laminated core (core product), 2... Laminate (core body), 2a... Center hole, 2b... Protrusion, 5... Magnet insertion hole (resin supply section), 100... Resin injection device, 200... Holding jig, 201... Base section, 202... Insertion post, 203... Groove, 204... Cooling hole, L1... Imaginary straight line (first imaginary straight line), L2... Imaginary straight line (second imaginary straight line).

Claims

[Claim 1] The insertion post extending upward from the base of the holding jig is inserted into the central hole of the core body, thereby holding the core body in the holding jig. The iron core body is pressurized together with the holding jig in the height direction of the holding jig, This includes heating the iron core body together with the holding jig while supplying molten resin to the resin supply section provided in the iron core body, The insertion post is provided with a plurality of cooling holes extending along the height direction, A method for manufacturing an iron core product, wherein the plurality of cooling holes are arranged at substantially uniform intervals so that they form a circular shape overall when viewed from the height direction. [Claim 2] The insertion post is provided with a groove extending along the height direction, The iron core body is provided with a projection that extends along the direction of extension of the central hole and is configured to fit into the groove. The method according to claim 1, wherein, when viewed from the height direction, there are no holes in the inner region of the insertion post surrounded by the plurality of cooling holes. [Claim 3] The method according to claim 2, wherein the plurality of cooling holes, when viewed from the height direction, are perpendicular to a first virtual line passing through the center of the insertion post and the groove, and are not located on a second virtual line passing through the center of the insertion post. [Claim 4] The method according to any one of claims 1 to 3, wherein the plurality of cooling holes are located in a region outside of half the radius of the insertion post in the radial direction of the insertion post, as viewed from the height direction. [Claim 5] The base part, The system includes an insertion post that extends upward from the base portion and is configured so that the central hole of the iron core body can be inserted through it, The insertion post is provided with a plurality of cooling holes that extend along the height direction of the insertion post, The iron core holder is a jig in which the plurality of cooling holes are arranged at substantially uniform intervals so as to form a circular shape when viewed from the height direction.

Images