Manufacturing method and manufacturing device of split core

Abstract

To provide a manufacturing method and a manufacturing device of a split core which can improve form accuracy of a single split core and as the whole of a motor core.SOLUTION: There is provided a manufacturing method of a split core comprising steps of: (1) arranging a plurality of split core laminates formed by temporarily joining a plurality of core plate materials constituting the split core with thermosetting adhesives to be laminated along an outer peripheral surface of an inner mold 1 to be formed as an annular split core aggregate; (2) arranging an outer mold 2 to surround the whole circumference of the split core aggregate; (3) heating the split core aggregate to first temperature at which the thermosetting adhesives are softened by a heater 3 in the inner mold 1 and a heater 4 in the outer mold 2 to be held while pressurizing the whole circumference of the split core aggregate to be bound by the outer mold 2; and (4) heating the split core aggregate to second temperature higher than the first temperature to harden the thermosetting adhesives after completion of the step (3), and its manufacturing device A.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a manufacturing method and a manufacturing apparatus for manufacturing split cores that constitute an annular motor core. [Background technology]

[0002] Many small motors mounted on home appliances, automobiles, etc. use split cores. As a method for manufacturing such split cores, Patent Document 1 discloses "a manufacturing method in which a laminated block is formed by stacking a plurality of plate-shaped elements having an adhesive applied to the surface thereof, and the laminated block is heated while being aligned to fix the plate-shaped elements of the laminated block to each other, thereby obtaining a laminated body." Patent Document 2 discloses "a manufacturing method for a laminated motor core in which a plurality of split core pieces are bonded and stacked to form annular core pieces by being connected to each other in the circumferential direction." [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 7278112 [Patent Document 2] Patent No. 6868719 Summary of the Invention [Problem to be solved by the invention]

[0004] In the manufacturing method of Patent Document 1, "laminates" equivalent to the split cores are manufactured one by one, so when multiple laminates are made into an annular motor core, it is difficult to obtain sufficient shape precision for the motor core as a whole. On the other hand, in the manufacturing method of Patent Document 2, multiple split cores are manufactured by arranging them in an annular shape, but the shape stability during manufacturing of the split cores is insufficient, and it is difficult to obtain sufficient shape precision for the split cores themselves.

[0005] An object of the present invention is to provide a method and an apparatus for manufacturing a split core, which can improve the shape accuracy of each split core and of the motor core as a whole. [Means for solving the problem]

[0006] According to one aspect of the present invention, there is provided the following method for manufacturing a split core. A method for manufacturing a split core constituting an annular motor core, comprising the steps of: A step (a) of temporarily bonding and laminating a plurality of core plate materials constituting a split core with a thermosetting adhesive to form a split core laminate, and arranging a plurality of split core laminates along an outer peripheral surface of an inner mold to form an annular split core assembly; a step (a) of arranging an outer mold so as to surround the entire circumference of the divided core assembly; (c) a step of heating the divided core assembly to a first temperature at which the thermosetting adhesive is softened by a heater in the inner die and a heater in the outer die while pressing and restraining the divided core assembly all around with the outer die, and maintaining the first temperature; A method for manufacturing a split core, comprising: after completion of step (c), a step (d) of heating the split core assembly to a second temperature higher than the first temperature to harden the thermosetting adhesive.

[0007] According to another aspect of the present invention, there is provided the following split core manufacturing apparatus. A split core manufacturing apparatus for manufacturing split cores constituting an annular motor core, comprising: the mold assembly includes an inner mold, an outer mold, heaters attached to the inner mold and the outer mold, respectively, and a pressurizing mechanism that pressurizes the outer mold toward the inner mold, the inner mold is capable of arranging a plurality of split core laminates, each of which is formed by temporarily bonding a plurality of core plate materials constituting a split core with a thermosetting adhesive and stacking them, along its outer circumferential surface, and holding the laminate as an annular split core assembly; The outer die is disposed so as to surround the entire periphery of the split core assembly, and is capable of applying pressure to and restraining the entire periphery of the split core assembly. Effect of the Invention

[0008] According to the present invention, the shape accuracy of each of the split cores and the motor core as a whole can be improved. [Brief description of the drawings]

[0009] [Figure 1] 1 is a perspective view showing an overall configuration of a split core manufacturing apparatus according to an embodiment of the present invention; [Diagram 2] 2 is a perspective view showing a state in which a plurality of split core laminates are arranged along the outer circumferential surface of an inner mold and held as an annular split core assembly in the split core manufacturing apparatus of FIG. 1. [Diagram 3] FIG. 3 is an enlarged perspective view of a main part of FIG. 2. [Figure 4] 2 is a perspective view showing an example of a split core laminate applied to the split core manufacturing apparatus of FIG. 1. [Diagram 5] 2 is an exploded perspective view showing main parts of an inner mold, a vertical restraining means, and a circumferential restraining means that constitute the split core manufacturing apparatus of FIG. 1. [Figure 6] 2 is a perspective view of a main portion of the split core manufacturing apparatus of FIG. 1, showing a state in which one split core laminate is arranged along the outer circumferential surface of an inner mold. FIG. [Figure 7] 4 is a perspective view of the main part showing a state in which the outer mold is moved toward the inner mold by the pressure mechanism from the state shown in FIGS. 2 and 3; FIG. [Figure 8A] FIG. 13 is a perspective view of a main part showing a state in which a heater installed in the inner mold is in an initial position. [Figure 8B] FIG. 4 is a perspective view of a main part showing a state in which the heater is mounted in the inner mold. [Figure 9] 4 is a perspective view of a main portion of the split core manufacturing apparatus of FIG. 1, showing a state in which a nut constituting a vertical restraint means is tightened by using a nut runner. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] An overall configuration of a split core manufacturing apparatus according to one embodiment of the present invention is shown in a perspective view in Fig. 1. Note that in Fig. 1, an outer frame and the like are omitted and the configuration is appropriately simplified. The split core manufacturing apparatus A shown in Fig. 1 includes an inner die 1, an outer die 2, heaters 3 and 4 attached to the inner die 1 and outer die 2, respectively, and a pressure mechanism 5 that presses the outer die 2 toward the inner die 1. Although details will be described later, the inner die 1 is capable of arranging a plurality of split core laminates B along its outer circumferential surface and holding them as an annular split core assembly C (see Figs. 2 and 3), and the outer die 2 is disposed so as to surround the entire periphery of the split core assembly C and is capable of pressurizing and restraining the entire periphery of the split core assembly C. 1 further includes a vertical restraint means 6 for restraining the split core assembly C in the vertical direction, and a circumferential restraint means 7 for restraining the split core assembly C in the circumferential direction. The vertical restraint means 6 and the circumferential restraint means 7 will be described in detail later.

[0011] FIG. 4 shows an example of a split core laminate B applied to the split core manufacturing apparatus A of FIG. 1 in a perspective view. The split core laminate B is formed by temporarily bonding and laminating a plurality of core plate materials B1 constituting the split core with a thermosetting adhesive B2. An electromagnetic steel plate is typically used as the core plate material B1. In addition, as the thermosetting adhesive B2, a material that can temporarily bond a plurality of core plate materials B1 when manufacturing the split core laminate B and has the property of softening at a first temperature and hardening, i.e., irreversibly hardening, at a second temperature higher than the first temperature when manufacturing the split core is used. In this embodiment, an epoxy-based thermosetting adhesive is used. The epoxy-based thermosetting adhesive used in this embodiment has the property of softening at about 100°C and hardening irreversibly at about 200°C. The method of temporarily bonding the core plate materials B1 together with the thermosetting adhesive is not particularly limited, but for example, the core plate materials B1 can be temporarily bonded using an interlayer adhesive sheet containing a thermosetting adhesive. Here, "temporary bonding" refers to a state in which the core plate materials are not heated to the above-mentioned second temperature and are not irreversibly hardened.

[0012] The split core manufactured in this embodiment has a shape obtained by dividing the stator into 24 parts in the circumferential direction, and the split core laminate B shown in Fig. 4 also has the same shape. That is, in this embodiment, when assembled into a stator, the split core laminate B has an annular yoke portion Ba and teeth portions Bb around which coils are wound.

[0013] Next, a method for manufacturing the split cores using the split core manufacturing apparatus A will be described. First, a plurality of split core laminates B (24 in this embodiment) are arranged along the outer circumferential surface of the inner mold 1 to form an annular split core assembly C (step (a)). In this embodiment, as shown in FIG. 5, a plurality of guide posts 71 (24 in this embodiment) are arranged on the outside of the inner mold 1 as inner circumferential direction restraining means 7. When arranging the split core laminates B along the outer circumferential surface of the inner mold 1, the teeth Bb of the split core laminates B are arranged so as to be fitted between adjacent guide posts 71, 71, as shown in FIG. 6. As a result, an annular split core assembly C is formed along the outer circumferential surface of the inner mold 1, as shown in FIGS. 2 and 3. In this embodiment, a lid 61 is used to restrain the split core assembly C in the up-down direction. As shown in FIG. 5, the lid 61 has a guide hole 611 through which a guide post 71 can be inserted. After forming the split core assembly C in the above-described manner, the guide post 71 is inserted into the guide hole 711 to attach the lid 61 so that the bottom surface of the lid 61 comes into contact with the top surface of the split core assembly C. Furthermore, as shown in FIG. 3, a nut 63 is attached to a bolt 62 fixed to the center of the inner die 1. The split core assembly C can be restrained in the up-down direction by tightening the nut 63, as will be described in detail later.

[0014] Next, the outer die 2 is arranged so as to surround the entire circumference of the split core assembly C (step (a)). In this embodiment, the outer die 2 is divided into two, and each inner peripheral surface 21, 21 has a semicircular shape that matches half of the outer peripheral surface of the split core assembly C. A pressure mechanism 5 is connected to each of the two divided outer die 2, and the pressure mechanism 5 moves the outer die 2 toward the inner die 1 along a pair of rails 51 as shown in FIG. 7. This allows the outer die 2 to be arranged so as to surround the entire circumference of the split core assembly C, and the outer die 2 can pressurize and restrain the entire circumference of the split core assembly C.

[0015] Thereafter, while the outer die 2 pressurizes and restrains the entire circumference of the divided core assembly C, the heater 3 in the inner die 1 and the heater 4 in the outer die 2 heat the thermosetting adhesive B2 to a first temperature at which the thermosetting adhesive B2 softens and maintains the temperature (step (c)). In this embodiment, the heater 3 is provided so as to be movable up and down, and its initial position is directly below the inner die 1 as shown in FIG. 3 and FIG. 8A. When performing step (c), the heater 3 is raised and positioned in the inner die 1 as shown in FIG. 8B. Meanwhile, the heater 4 is built into the outer die 2 from the beginning. Both the heater 3 and the heater 4 have a temperature adjustment function, and in step (c), the temperature is raised to a first temperature and maintained at that temperature. As described above, the thermosetting adhesive B2 used in this embodiment has the property of softening at about 100°C and hardening irreversibly at about 200°C. Therefore, in this embodiment, in step (c), the first temperature is set to 100°C and maintained for 15 minutes. The pressure applied to the split core assembly C by the outer die 2 can be adjusted by the pressure applied by the pressure mechanism 5, and can be set to, for example, about 350N.

[0016] In this embodiment, in step (c), as described above, the outer die 2 applies pressure to the entire circumference of the split core assembly C to restrain it, and the vertical restraining means 6 and the circumferential restraining means 7 also restrain the split core assembly C in the vertical and circumferential directions. In this embodiment, the vertical direction of the split core assembly C is restrained by tightening the nut 63 (FIG. 3) constituting the vertical restraining means 6 using a nut runner 64 as shown in FIG. 9. The nut runner 64 is movable up and down, and can tighten the nut 63 with a torque of about 40 Nm, for example. Meanwhile, in this embodiment, the circumferential direction of the split core assembly C is restrained by fitting the teeth Bb of the split core laminate B between adjacent guide posts 71, 71 as shown in FIG. 5.

[0017] After the step (c) is completed, the divided core assembly C is heated to a second temperature higher than the above-mentioned first temperature to cure, i.e., irreversibly cure, the thermosetting adhesive B2 (step (d)). In this embodiment, the second temperature is set to 200°C, which is higher than the above-mentioned first temperature (100°C). Here, step (d) can be carried out successively with the above-mentioned step (c). In this case, in step (d), after the completion of step (c), the entire circumference of the divided core assembly C is pressurized and restrained by the outer die 2, while the heater 3 in the inner die 1 and the heater 4 in the outer die 2 heat (increase the temperature) from the first temperature (100°C in this embodiment) to the second temperature (200°C in this embodiment) and maintain it. The maintenance time can be about 15 minutes, the same as in step (c). The pressure applied to the divided core assembly C by the outer die 2 can be about 350 N, the same as in step (c), and can be higher or lower than the pressure in step (c) depending on the situation.

[0018] On the other hand, step (d) can also be performed discontinuously with step (c) described above. In this case, an inner mold and an outer mold (hereinafter referred to as a "second inner mold" and a "second outer mold", respectively) having the same shapes as the inner mold 1 and the outer mold 2 described above are separately prepared, and the entire circumference of the divided core assembly is pressurized and constrained by the second outer mold, while the heater in the second inner mold and the heater in the second outer mold are heated to the second temperature and maintained at that temperature. When step (d) is performed using the second inner mold and the second outer mold in this manner, the heater in the second inner mold and the heater in the second outer mold can be heated to the second temperature in advance, so that productivity can be improved compared to the case where step (d) is performed continuously with step (c). In other words, the time required to heat the heater 3 in the inner mold 1 and the heater 4 in the outer mold 2 from the first temperature to the second temperature can be omitted, and the time required to cool the heater 3 in the inner mold 1 and the heater 4 in the outer mold 2 from the second temperature to the first temperature in order to carry out step (c) for the next production after step (e) is completed can be omitted.

[0019] As described above, the method for manufacturing a split core according to the present invention includes steps (A) to (D), and thus the shape accuracy of the split cores and the motor core as a whole can be improved. In particular, in step (C), the split core assembly C is pressurized and restrained all around by the outer die 2, while the heater 3 in the inner die 1 and the heater 4 in the outer die 2 heat the split core assembly C to a first temperature at which the thermosetting adhesive B2 softens, and the shape of the split core laminate B and the split core assembly C, which is an assembly of the split core laminates B, can be corrected to a shape that matches the shape of the final product as a motor core. This improves the shape accuracy of the split cores and the motor core as a whole. Furthermore, in this embodiment, the split core assembly C is restrained in the vertical and circumferential directions in step (C), so that the shape accuracy can be further improved. In addition, step (D) can be performed continuously with step (C) from the viewpoint of improving the shape accuracy, and can be performed discontinuously with step (C) from the viewpoint of improving productivity. In any case, it is preferable to restrain the split core assembly C in step (D) also in the vertical and circumferential directions.

[0020] Although the embodiment of the present invention has been described above, the present invention is not limited to this embodiment. For example, in this embodiment, the outer die 2 is divided into two, but it may be divided into three or four. Also, in this embodiment, the heater 3 is provided so that it can be raised and lowered, but it may be built into the inner die 1 from the beginning. Furthermore, the shape and type of the split core manufactured in the present invention are not limited to the shape and type shown in FIG. 4, and it is also possible to manufacture a split core that constitutes a rotor, for example. [Explanation of symbols]

[0021] A Split core manufacturing equipment B. Split core laminate Ba York Bb Teeth B1 Core board B2 Thermosetting adhesive C. Split core assembly 1 Inner mold 2 Outer mold 21 Inner surface 3 Heater 4 Heater 5. Pressure mechanism 51 Rail 6 Vertical restraint means 61 Lid 62 Volts 63 Nut 64 Nutrunner 7 Circumferential restraint means 71 Guide Post

Claims

1. A method for manufacturing a split core constituting an annular motor core, comprising the steps of: A step (a) of temporarily bonding a plurality of core plate materials constituting a split core with a thermosetting adhesive and laminating the plurality of split core laminates, which are arranged along the outer circumferential surface of an inner mold, to form an annular split core assembly; a step (a) of arranging an outer mold so as to surround an entire periphery of the divided core assembly; a step (c) of heating the divided core assembly to a first temperature at which the thermosetting adhesive softens, by a heater in the inner die and a heater in the outer die, while pressing and restraining the entire circumference of the divided core assembly by the outer die, and maintaining the first temperature; A method for manufacturing a split core, comprising: after completion of step (c), a step (d) of heating the split core assembly to a second temperature higher than the first temperature to harden the thermosetting adhesive.

2. The method for manufacturing a split core according to claim 1 , wherein in the step (c), the split core assembly is also constrained in a vertical direction and a circumferential direction.

3. 3. The method for manufacturing a split core according to claim 1 or 2, wherein the step (e) is carried out successively with the step (c), and the split core assembly is heated to the second temperature and maintained at that temperature by a heater in the inner mold and a heater in the outer mold while the outer mold pressurizes and restrains the entire circumference of the split core assembly by means of the outer mold.

4. 3. The method for manufacturing a split core according to claim 1 or 2, wherein the step (e) is performed discontinuously with the step (c), and an inner mold and an outer mold (hereinafter referred to as a "second inner mold" and a "second outer mold", respectively) having the same shapes as the inner mold and the outer mold are separately prepared, and the split core assembly is heated to the second temperature and maintained at that temperature by a heater in the second inner mold and a heater in the second outer mold while the entire circumference of the split core assembly is pressurized and restrained by the second outer mold.

5. A split core manufacturing apparatus for manufacturing split cores constituting an annular motor core, comprising: the mold assembly includes an inner mold, an outer mold, heaters attached to the inner mold and the outer mold, respectively, and a pressurizing mechanism that pressurizes the outer mold toward the inner mold, the inner mold is capable of arranging a plurality of split core laminates, each of which is formed by temporarily bonding a plurality of core plate materials constituting a split core with a thermosetting adhesive and stacking them, along its outer circumferential surface, and holding the laminate as an annular split core assembly; The outer die is disposed so as to surround the entire periphery of the split core assembly, and is capable of applying pressure to and restraining the entire periphery of the split core assembly.

6. 6. The split core manufacturing apparatus according to claim 5, further comprising: a vertical restraining means for restraining the split core assembly in a vertical direction; and a circumferential restraining means for restraining the split core assembly in a circumferential direction.

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