Electric motor and method for manufacturing core

Abstract

The invention provides an electric motor using an annular iron core, the iron core is provided with groove parts at constant intervals at the edge part, and protrusions formed by processing are arranged in the groove parts.

Description

Technical Field

[0001] The present disclosure relates to a motor and a method for manufacturing an iron core. Background Art

[0002] It is known that the core of a motor is formed of a steel plate (for example, Patent Document 1).

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Microfilm of Japanese Utility Model Application No. 53-133367 (Japanese Utility Model Application Publication No. 55-49882) Summary of the invention

[0006] Problems to be solved by the invention

[0007] However, when forming a steel sheet, a protrusion is sometimes formed on the edge of the steel sheet. If a protrusion is formed on the edge, the protrusion is hooked on other parts, and the iron core cannot be assembled with high accuracy.

[0008] By increasing the number of steps required to form the steel sheet, it is possible to prevent protrusions from being formed on the steel sheet. However, there is a problem that the lead time or cost required to manufacture the motor increases due to the increase in the number of steps required.

[0009] Therefore, there is a need for a motor that does not have protrusions that get caught on other parts, can be assembled with high precision, and can be manufactured at low cost.

[0010] Solutions to Solve Problems

[0011] A motor using an annular iron core, wherein the iron core has grooves at regular intervals on an edge thereof, and protrusions formed by processing are arranged in the grooves.

[0012] A method for manufacturing an annular iron core includes processing a steel plate to form an edge portion having a groove, and arranging a protrusion formed by the processing in the groove.

[0013] Effects of the Invention

[0014] According to one aspect of the present disclosure, a motor can be assembled with high precision and can be manufactured at low cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a top view showing an example of an iron core.

[0016] Figure 2 yes Figure 1 A partial enlarged view of the iron core.

[0017] Figure 3This is a diagram for explaining the slotting press process.

[0018] Figure 4A This is a diagram showing an example of a die used for slotting press working.

[0019] Figure 4B This is a diagram showing an example of a die used for slotting press working.

[0020] Figure 4C This is a diagram showing an example of a die used for slotting press working.

[0021] Figure 5A It is a diagram for explaining the assembly process of the rotor.

[0022] Figure 5B It is a diagram for explaining the assembly process of the rotor.

[0023] Fig. 6A It is a diagram for explaining the assembly process of the rotor.

[0024] Figure 6B It is a diagram for explaining the assembly process of the rotor.

[0025] Figure 6C It is a diagram for explaining the assembly process of the rotor.

[0026] Fig. 7A This is a diagram showing an example of a rotor.

[0027] Figure 7B This is a diagram showing an example of a rotor.

[0028] Figure 7C This is a diagram showing an example of a rotor.

[0029] Fig. 8A This is a diagram showing another example of a die used for the slotting press working.

[0030] Figure 8B This is a diagram showing another example of a die used for the slotting press working.

[0031] Figure 8C This is a diagram showing another example of a die used for the slotting press working.

[0032] Fig. 9 It is a top view showing an example of a stator core.

[0033] Fig.10 yes Fig. 9 A partial enlarged view of the iron core.

[0034] Fig.11 This is a diagram showing an example of a stator mounted on a sheath. DETAILED DESCRIPTION

[0035] Hereinafter, an electric motor using an iron core involved in an embodiment of the present disclosure and a method for manufacturing the iron core are described using the accompanying drawings. It should be noted that all combinations of the features described in the following embodiments are not necessarily necessary to solve the problem. In addition, detailed descriptions beyond the necessary level are sometimes omitted. In addition, the following descriptions of the embodiments and the accompanying drawings are provided to enable those skilled in the art to fully understand the present disclosure and are not intended to limit the claims.

[0036] The iron core is a component of the motor and serves as a path for magnetic flux. The iron core includes a rotor iron core and a stator iron core.

[0037] Figure 1 It is a top view showing an example of an iron core. Figure 1 The iron core 1 shown is a rotor iron core. The iron core 1 is an annular plate. The iron core 1 is manufactured by processing an electromagnetic steel plate into a predetermined annular shape.

[0038] Figure 2 yes Figure 1 The iron core 1 is a partially enlarged view of the iron core 1. The iron core 1 has grooves 12 at a constant interval on the edge portion 11. The edge portion 11 is located on the outer circumference or inner circumference of the annular iron core 1. The groove 12 is a recessed portion formed from the outer circumference toward the inner side of the iron core 1, or a recessed portion formed from the inner circumference toward the outer side of the iron core 1. The groove 12 is provided with a protrusion 13 formed by processing.

[0039] The depth of the groove 12 is formed deeper than the height of the protrusion 13. The depth of the groove 12 is the distance from the inner periphery to the bottom of the groove 12. In other words, the depth of the groove 12 is the distance in the radial direction of the iron core 1 from the bottom of the groove 12 to the inner periphery. The depth of the groove 12 is, for example, 0.3 [mm] or more.

[0040] The iron core 1 is formed, for example, by slot punching. In the slot punching, a punching machine repeatedly punches out a part of the iron core 1 using a die for punching out a part of the iron core 1, thereby manufacturing the iron core 1.

[0041] The portion 14 where the edge portion 11 and the groove portion 12 meet may be formed in an arc shape. In other words, the boundary portion between the edge portion 11 and the groove portion 12 may be rounded.

[0042] Figure 3 This is a diagram for explaining the slotting punching process. In the slotting punching process, after the punching machine punches out a part of the iron core 1 through a punching action, the iron core 1 is rotated by a predetermined angle and the next punching is performed. Figure 3 In the example shown, each time a punching operation is performed, the core 1 is rotated by α°, and the next punching operation is performed. The punching machine repeatedly performs such operations to process the core 1 into a predetermined shape.

[0043] A protrusion 13 is formed at a boundary portion between a portion of the iron core 1 formed by one punching operation and a portion of the iron core 1 formed by the next punching operation. The protrusion 13 is a burr. That is, the protrusion 13 is made of the same material as the electromagnetic steel sheet constituting the iron core 1. The height of the protrusion 13 is, for example, 0.1 [mm] or less.

[0044] When the notching press working is performed, the process is performed so that the protrusion 13 is arranged in the groove portion 12. In other words, the press machine performs the notching press working using a die having a shape in which the protrusion 13 is arranged in the groove portion 12.

[0045] Figure 4A to Figure 4C 1 is a diagram showing an example of a die used for slotting and punching. Specifically, Figure 4A It is a top view of the upper mold. Figure 4B It is a three-dimensional diagram of the upper mold. Figure 4C It is a three-dimensional diagram of the lower mold.

[0046] The upper die has a convex portion for forming the electromagnetic steel sheet into a predetermined shape. The convex portion has an outer circumference forming portion UO for forming the outer circumference of the core 1 and an inner circumference forming portion UI for forming the inner circumference of the core 1. In addition, the convex portion has a groove forming portion UG for forming the groove portion 12 of the core 1.

[0047] The lower die has a recessed portion for forming the electromagnetic steel sheet into a predetermined shape. The recessed portion also has an outer periphery forming portion LO for forming the outer periphery of the iron core 1 and an inner periphery forming portion LI for forming the inner periphery of the iron core 1. In addition, the recessed portion has a groove forming portion LG for forming the groove portion 12 of the iron core 1.

[0048] In the slotting press process, the convex part of the upper die is inserted strongly into the concave part of the lower die while the electromagnetic steel sheet is arranged between the upper die and the lower die, thereby forming a hole having the same shape as the convex part and the concave part or a shape having the same shape as a part of the convex part and the concave part in the electromagnetic steel sheet.

[0049] Figure 5A and Figure 5B as well as Figure 6A to Figure 6C The diagram is for explaining the assembly process of the rotor using the iron core 1 . Figure 7A to Figure 7C FIG. 1 is a diagram showing an example of the rotor 100 removed from the guide jig J. FIG.

[0050] In the assembly process of the rotor 100, first, the rotor plate 101 is mounted on a guide jig J (see Figure 5A and Figure 5B Next, the plurality of cores 1 are mounted on the guide fixture J (see Figure 5A and Figure 5B). The inner circumferences of the plurality of cores 1 are guided by the outer circumference of the guide jig J and a predetermined number of cores 1 are stacked.

[0051] Assuming that the protrusion 13 is provided on the inner periphery of the iron core 1, the protrusion 13 will be hooked on the outer periphery of the guide jig J. In this case, the iron core 1 cannot be assembled with high precision. However, the protrusion 13 of the iron core 1 of the present embodiment is arranged in the groove portion 12, so the protrusion 13 will not be hooked on the outer periphery of the guide jig J. Therefore, the iron core 1 can be assembled with high precision.

[0052] When a plurality of cores 1 are stacked, another rotor plate 101 is mounted on the guide jig J. That is, the plurality of cores 1 and the plurality of magnets 102 are sandwiched between the two rotor plates 101. Next, the two rotor plates 101 are fixed by bolts 103. Next, the magnets 102 are attached to the outer periphery of the core 1 (see Figure 6A to Figure 6C Finally, remove the rotor 100 from the guide fixture J (refer to Figure 7A to Figure 7C ).

[0053] As described above, when the boundary between the edge 11 and the groove 12 is rounded, the core 1 can be smoothly inserted into the guide jig J compared to a case where a corner is formed at the boundary between the edge 11 and the groove 12 .

[0054] When the edge portion 11 is located at the inner circumference, the edge portion 11 may also be in contact with the shaft. For example, the shaft may be hot-pressed and fitted to the plurality of cores 1 after the plurality of cores 1 are assembled. In this case, the edge portion 11 is in direct contact with the shaft. That is, the core 1 of this embodiment is provided with the protrusion 13 in the groove 12, so the protrusion 13 does not contact the shaft. Therefore, the core 1 and the shaft can be assembled with high precision.

[0055] In addition, the molds used for slotting and stamping are not limited to Figure 4A to Figure 4C The mold shown.

[0056] Figure 8A to Figure 8C 2 is a diagram showing another example of a die for slotting and punching. Specifically, Fig. 8A It is a top view of the upper mold. Figure 8B It is a three-dimensional diagram of the upper mold. Figure 8C It is a three-dimensional diagram of the lower mold.

[0057] Fig. 8A by Figure 8B The upper mold shown in the figure includes an outer periphery forming portion UO for forming the outer periphery of the core 1 and an inner periphery forming portion UI for forming the inner periphery of the core 1. Figure 8C The lower die shown in the figure also includes an outer periphery forming portion LO for forming the outer periphery of the core 1 and an inner periphery forming portion LI for forming the inner periphery of the core 1 .

[0058] The outer circumference forming portion UO and the inner circumference forming portion UI of the upper die are formed in phases that are offset from each other. The outer circumference forming portion LO and the inner circumference forming portion LI of the lower die are also formed in phases that are offset from each other. Thus, the load applied to the electromagnetic steel sheet during the slotting and punching process is dispersed. As a result, the electromagnetic steel sheet does not deform during processing, and processing can be performed with high precision.

[0059] In the above embodiment, the rotor core is described, but the core 1 may be a stator core.

[0060] Fig. 9 1 is a plan view showing an example of a stator core. The core 2 is an annular plate. The core 2 is manufactured by processing an electromagnetic steel plate into a predetermined shape, for example.

[0061] Fig.10 yes Fig. 9 2 is a partial enlarged view of the core 2. The core 2 has grooves 22 at regular intervals in the edge 21. When the core 2 is a stator core, the edge 21 is located at the outer periphery of the core 2. The groove 22 is provided with a protrusion 23 formed by processing.

[0062] When the edge portion 21 is located on the outer periphery of the core 2 , the edge portion 21 may be in contact with the sheath.

[0063] Fig.11 201 is a diagram showing an example of a stator core mounted on a sheath. The sheath 201 is a component for cooling the motor. In order to improve the cooling performance, it is known that the sheath 201 and the core 2 are assembled without providing a gap by hot pressing and anaerobic adhesive. A groove 22 is formed in the edge 21 of the core 2 of the present embodiment, and a protrusion 23 is arranged in the groove 22. Therefore, the protrusion 23 does not contact the sheath 201, so that the core 2 and the sheath 201 can be assembled with high precision.

[0064] The core 2 is not limited to the slotting and punching process, and can also be processed by laser. When the outer periphery and the inner periphery of the core 2 are processed by laser processing, the protrusion 23 is easily formed at the processing start point and the processing end point where the laser is irradiated. Therefore, by arranging the processing start point and the processing end point in the groove portion 22, the protrusion 23 can be arranged in the groove portion 22. Here, the protrusion 23 refers to a burr.

[0065] In addition, when the outer periphery of the core 2 is formed by laser processing, a protrusion 23 may be generated at a position where the processing direction changes. The position where the processing direction changes is a position where the moving direction of the processing head of the laser processing machine changes from the positive direction of the control axis to the negative direction or from the negative direction to the positive direction. The protrusion 23 is formed, for example, by a change in the acceleration of the control axis of the laser processing machine and the backlash of the ball screw. The protrusion 23 is called a quadrant protrusion.

[0066] If the protrusion 23 is formed on the outer periphery of the stator core of the core 2 , the protrusion 23 and the sheath 201 may be caught, and the two may not be assembled with high accuracy.

[0067] Therefore, the core 2 of the present embodiment includes the groove 22 in the edge 21 where the quadrant protrusion is formed, and the protrusion 23 is arranged in the groove 22. This prevents the protrusion 23 from being caught on the sheath 201.

[0068] In addition, the present disclosure is not limited to the above-mentioned embodiment, and can be appropriately modified within the scope not departing from the gist. For example, any component of the embodiment of the present disclosure can be modified, or any component of the embodiment can be omitted.

[0069] Explanation of symbols

[0070] 1—iron core; 11—edge portion; 12—groove portion; 13—protrusion; 14—portion where the edge portion and the groove portion meet; 101—rotor plate; 102—magnet; 103—bolt; 2—iron core; 21—edge portion; 22—groove portion; 23—protrusion; 201—sheath; J—guide fixture.

Claims

1. An electric motor using an annular iron core, characterized in that: The core has grooves at regular intervals on the edge. The iron core in which the protrusion formed by processing is arranged in the groove portion is used.

2. The electric motor according to claim 1, characterized in that A portion where the edge portion and the groove portion meet is formed in an arc shape.

3. The electric motor according to claim 1 or 2, characterized in that: The edge portion is located on the inner periphery, and the edge portion is in contact with the shaft.

4. The electric motor according to claim 1 or 2, characterized in that: The edge portion is located at the outer periphery, and the edge portion is in contact with the sheath.

5. A method for manufacturing an iron core, which is a method for manufacturing an annular iron core, characterized in that: It includes processing to form an edge portion having a groove on the steel plate, The protrusion formed by the above-mentioned processing is arranged in the above-mentioned groove portion.

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