Laminated iron core and electric motor equipped with same

Abstract

A laminated iron core according to the present invention is provided with a laminate formed by laminating a plurality of steel plates, and a two-dimensional matrix cord provided to a side surface of the laminate, wherein the two dimensional matrix cord is inclined relative to the lamination direction in which the plurality of steel plates are laminated.

Description

[Technical Field]

[0001] The present disclosure relates to a laminated core and an electric motor including the same. In particular, the present disclosure relates to a laminated core having a two-dimensional matrix code and an electric motor including the same. [Background technology]

[0002] Conventionally, in order to enhance traceability, a technology has been known in which parts, intermediate assemblies, and final products are printed with a laser or other means to provide ID (identity) marks. Quality control of parts is carried out by inputting information such as manufacturing conditions at the time of production and part lot numbers into the ID marks. Such ID marks are generally printed on a flat surface where the entire ID mark can be printed.

[0003] As an example of this type of prior art, Patent Document 1 discloses a rotor laminated core provided with an identification code. The rotor laminated core of Patent Document 1 includes a laminate body in which a plurality of punched members are stacked, and an identification code is provided on the outer surface of the punched member that forms the uppermost or lowermost layer of the laminate body, i.e., on the main surface of the laminate body.

[0004] However, the main surfaces of the laminates that make up the armature or stator, etc., are easily hidden by windings or other components. Therefore, it is conceivable to provide the identification code on the side surface of the laminate rather than the main surface. However, because the side surface is formed by stacking punched members, there is a problem in that the boundaries between adjacent punched members become noise, resulting in many reading errors. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 2018-176230 Summary of the Invention

[0006] The present disclosure has been made to solve such problems, and aims to provide a laminated core that can suppress the occurrence of reading errors in two-dimensional matrix codes, and an electric motor equipped with the same.

[0007] In order to achieve the above object, one embodiment of a laminated core according to the present disclosure comprises a laminate formed by stacking a plurality of steel plates, and a two-dimensional matrix code provided on a side of the laminate, wherein the two-dimensional matrix code is inclined with respect to the stacking direction in which the plurality of steel plates are stacked.

[0008] Furthermore, an electric motor according to another aspect of the present disclosure includes the laminated core according to the above aspect.

[0009] According to the present disclosure, it is possible to provide a laminated core that can suppress the occurrence of reading errors of a two-dimensional matrix code, and an electric motor including the same. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is an exploded perspective view showing an electric motor according to an embodiment. [Figure 2] FIG. 2 is a flow chart showing an example of a production process for the electric motor of FIG. [Figure 3A] FIG. 3A is a diagram showing a two-dimensional matrix code according to a comparative example. [Figure 3B] FIG. 3B is a diagram showing a two-dimensional matrix code provided in the electric motor of FIG. [Figure 4A] FIG. 4A is a diagram showing a two-dimensional matrix code when the inclination angle with respect to the stacking direction is 0 degrees. [Figure 4B] FIG. 4B is a diagram showing a two-dimensional matrix code when the inclination angle with respect to the stacking direction is 5 degrees. [Figure 4C] FIG. 4C is a diagram showing a two-dimensional matrix code when the inclination angle with respect to the stacking direction is 10 degrees. [Figure 4D]FIG. 4D is a diagram showing a two-dimensional matrix code when the inclination angle with respect to the stacking direction is 15 degrees. [Figure 4E] FIG. 4E is a diagram showing a two-dimensional matrix code when the inclination angle with respect to the stacking direction is 30 degrees. [Figure 4F] FIG. 4F is a diagram showing a two-dimensional matrix code when the inclination angle with respect to the stacking direction is 45 degrees. [Figure 5] FIG. 5 is a graph showing the readability at each tilt angle in FIGS. 4A to 4F. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. Note that each of the embodiments described below represents a specific example of the present disclosure. Therefore, the numerical values, shapes, materials, components, arrangement positions and connection forms of the components, etc. shown in the following embodiments are merely examples and are not intended to limit the present disclosure. Therefore, among the components in the following embodiments, components that are not described in the independent claims that represent the highest concept of the present disclosure will be described as optional components.

[0012] It should be noted that the drawings are schematic diagrams and are not necessarily strict illustrations. In the drawings, the same reference numerals are used to designate substantially the same components, and redundant explanations will be omitted or simplified.

[0013] In this specification and drawings, the X-axis, Y-axis, and Z-axis represent the three axes of a three-dimensional Cartesian coordinate system, and for convenience, the Z-axis direction is made to coincide with the stacking direction in which multiple steel plates are stacked. The X-axis and Y-axis are mutually orthogonal and are both orthogonal to the Z-axis.

[0014] (Embodiment) First, the configuration of an electric motor 10 according to an embodiment will be described with reference to Fig. 1. Fig. 1 is an exploded perspective view showing an electric motor 10 according to an embodiment.

[0015] As shown in FIG. 1 , electric motor 10 includes a frame 12, a stator 14, a rotor 16, a commutator 18, brushes 20, a brush holder 22, a seal ring 24, and bearings 13 and 26. Electric motor 10 is an inner rotor motor in which rotor 16 is disposed inside stator 14. Electric motor 10 includes permanent magnets 28 in stator 14 and windings 32 in rotor 16. In other words, in electric motor 10, rotor 16 is the armature. As will be described in detail later, electric motor 10 includes a two-dimensional matrix code 38 on the side surface of laminated core 30 of rotor 16. In the following description, the axial direction refers to the axial direction of rotating shaft 34, the radial direction refers to the radial direction of rotating shaft 34, and the circumferential direction refers to the circumferential direction of rotating shaft 34. In this embodiment, the axial direction coincides with the stacking direction (Z-axis direction) in which multiple steel plates 40 are stacked.

[0016] The frame 12 is a housing that houses the stator 14, the rotor 16, etc. The frame 12 is an outer shell member of the electric motor 10. The frame 12 is a cylindrical body with a bottom. The frame 12 is open on one side in the axial direction. The frame 12 supports a bearing 13 at its bottom. For example, the frame 12 is made of an iron member with high magnetic permeability.

[0017] The stator 14 generates a magnetic force that acts on the rotor 16. The stator 14 has a plurality of permanent magnets 28. The plurality of permanent magnets 28 are arranged side by side at intervals in the circumferential direction. The plurality of permanent magnets 28 are fixed to the inner surface of the frame 12. Each of the plurality of permanent magnets 28 extends in the circumferential direction.

[0018] The rotor 16 rotates relative to the stator 14. As described above, the rotor 16 is disposed inside the stator 14, and a small air gap is formed between the rotor 16 and the stator 14 in the radial direction. The rotor 16 has a laminated core 30, a plurality of windings 32, and a rotating shaft 34.

[0019] The laminated core 30 is a laminated core for an electric motor that constitutes part of the electric motor 10. The laminated core 30 is a rotor core and an armature core wound with a plurality of windings 32. The laminated core 30 has laminations 36 and a two-dimensional matrix code 38.

[0020] The laminate 36 is a laminate formed by stacking a plurality of steel plates 40 (see FIG. 3B) in the axial direction. Each of the plurality of steel plates 40 is an electromagnetic steel plate. For example, the thickness of each of the plurality of steel plates 40 is approximately 0.5 mm. The laminate 36 has a plurality of teeth 42. Each of the plurality of teeth 42 protrudes radially outward. The plurality of teeth 42 are arranged at equal intervals in the circumferential direction. In other words, the plurality of teeth 42 extend radially in a direction perpendicular to the axis A of the rotating shaft 34 (radial direction).

[0021] The multiple windings 32 are armature windings wound around the laminated core 30. The multiple windings 32 are wound around multiple teeth 42 of the laminated core 30. The multiple windings 32 are wound so that a magnetic force acting on the stator 14 is generated when a current flows through them. When a current is supplied to the multiple windings 32, the rotor 16 rotates relative to the stator 14. For example, the electric wires that make up the multiple windings 32 are insulated wires, and have a conductive wire made of a conductive material such as copper as a core wire, and an insulating film that coats the conductive wire.

[0022] The rotating shaft 34 is fixed to the laminated core 30 in a state in which it penetrates the laminated core 30 in the axial direction. For example, the rotating shaft 34 is made of a metal rod or the like. The rotating shaft 34 is fixed to the laminated core 30 by being press-fitted or shrink-fitted into a central hole formed in the laminated core 30. A bearing 26 for rotatably supporting the rotating shaft 34 is provided at one end of the rotating shaft 34. The other end of the rotating shaft 34 is rotatably supported by a bearing 13 provided in the frame 12.

[0023] The two-dimensional matrix code 38 is provided on the side surface of the laminate 36. The two-dimensional matrix code 38 is provided on the outer surface of the laminate 36, i.e., on the outer surfaces of the teeth 42. The side surface of the laminate 36 is formed by lining up the side surfaces of the multiple steel plates 40 in the stacking direction. As will be described in detail later, the two-dimensional matrix code 38 is inclined with respect to the stacking direction in which the multiple steel plates 40 are stacked.

[0024] The commutator 18 is attached to the rotating shaft 34. The commutator 18 rotates together with the rotating shaft 34. The commutator 18 has a plurality of commutator segments 44. The plurality of commutator segments 44 are electrically connected to the plurality of windings 32.

[0025] The brush 20 is a power supply brush for supplying power to the plurality of windings 32. The brush 20 is in contact with the plurality of commutator segments 44, and an armature current supplied to the brush 20 via a power supply terminal flows through the plurality of windings 32 via the commutator segments 44. For example, the brush 20 is a conductive carbon brush made of carbon, and is in the form of a long, substantially rectangular parallelepiped.

[0026] The brush holder 22 holds the brush 20. The brush holder 22 is fixed to the frame 12 so as to close the opening of the frame 12.

[0027] The seal ring 24 is a ring-shaped member provided to fill the gap between the brush holder 22 and the frame 12 .

[0028] In the electric motor 10 configured as described above, the current supplied to the brushes 20 flows as an armature current (drive current) through the multiple windings 32 wound around the rotor 16 via the commutator 18. This generates magnetic flux in the rotor 16. The magnetic flux generated in the rotor 16 interacts with the magnetic flux generated from the stator 14, generating a magnetic force that serves as torque to rotate the rotor 16. At this time, the direction of the current flow is switched depending on the positional relationship between the brushes 20 and the commutator segments 44 of the commutator 18 when they come into contact with each other. By switching the direction of the current flow in this way, a rotational force in a fixed direction is generated by the magnetic repulsive and attractive forces generated between the stator 14 and the rotor 16, causing the rotor 16 to rotate about the rotation axis 34.

[0029] Next, a manufacturing process for the electric motor 10 according to this embodiment will be described with reference to Fig. 2. Fig. 2 is a flow chart showing an example of a manufacturing process for the electric motor 10 of Fig. 1.

[0030] Here, the production process for the electric motor 10 includes an armature process for producing an armature, and an assembly and inspection process for assembling the produced armature with other parts and inspecting them. In Fig. 2, steps S1 to S10 are the armature process, and steps S11 to S15 are the assembly and inspection process.

[0031] 2, first, the laminated core 30 is formed by pressing (step S1). Specifically, a plurality of steel plates 40 are stacked and then pressure is applied to form a laminate 36. After the laminate 36 is formed, a two-dimensional matrix code 38 is printed on the side of the laminate 36 using a laser or the like (step S2).

[0032] Next, the rotating shaft 34 is press-fitted into the laminated core 30 (step S3), and the commutator 18 is press-fitted into the rotating shaft 34 press-fitted into the laminated core 30 (step S4).

[0033] After the commutator 18 is press-fitted onto the rotating shaft 34, the windings 32 are wound around the laminated core 30 (step S5), and fusing is performed to electrically connect the plurality of windings 32 and the plurality of commutator segments 44, respectively (step S6).

[0034] After fusing, the outer periphery of the commutator 18 is cut (step S7), and chips generated by the cutting are removed (step S8).

[0035] After removing the chips, the balance of the armature is measured (step S9), and electrical tests (finished armature inspection) are performed on the completed armature, such as a resistance test between the commutator segments 44 and an insulation resistance test between the windings 32 and the laminated core 30 (step S10).

[0036] After the electrical inspection, the brush holder 22 and bearing 26, etc., which have the brush 20 temporarily held therein, are supplied to the armature (step S11), and these are assembled by being pressed into the armature, etc., and the brush 20 is released (step S12).

[0037] Next, the frame 12 is assembled by fixing a plurality of permanent magnets 28 to the inner surface of the frame 12 (step S13), and an armature or the like is press-fitted into the assembled frame 12, which is then magnetized (step S14).

[0038] Finally, a characteristic inspection and a bearing height inspection from the opening side flange end face of the frame 12 to the upper end face of the bearing 26 are carried out (step S15), and the process ends.

[0039] In this manner, the electric motor 10 is produced.

[0040] Next, the two-dimensional matrix code 38 according to this embodiment will be described with reference to Fig. 3. Fig. 3A is a diagram showing a two-dimensional matrix code 100 according to a comparative example. Fig. 3B shows the two-dimensional matrix code 38 provided in the electric motor 10 of Fig. 1.

[0041] As shown in FIGS. 3A and 3B, the two-dimensional matrix code 38 and the two-dimensional matrix code 100 are DMCs (Data Matrix Codes). A DMC is composed of a plurality of substantially square unit cells arranged in rows and columns. Each unit cell is a white cell that is substantially white or a black cell that is substantially black. The arrangement of the white cells and black cells is associated with predetermined information. By reading the arrangement of the white cells and black cells, the predetermined information associated with the arrangement can be obtained. Each of the two-dimensional matrix codes 38 and 100 includes a quiet zone, a clock pattern, and an alignment pattern. The higher the reading accuracy of the quiet zone, the clock pattern, and the alignment pattern, the better the readability of the two-dimensional matrix code.

[0042] In this embodiment, when one of the row and column directions of the two-dimensional matrix code is not inclined with respect to the stacking direction in which the multiple steel plates are stacked, that is, is parallel to the stacking direction, the two-dimensional matrix code is considered to be not inclined with respect to the stacking direction. When the row and column directions of the two-dimensional matrix code are inclined with respect to the stacking direction in which the multiple steel plates are stacked, that is, are not parallel to the stacking direction, the two-dimensional matrix code is considered to be inclined with respect to the stacking direction. The inclination angle of the two-dimensional matrix code with respect to the stacking direction in which the multiple steel plates are stacked is the angle formed by the stacking direction and the column direction of the two-dimensional matrix code.

[0043] As shown in FIG. 3A, a two-dimensional matrix code 100 according to the comparative example is configured by arranging white cells 102 and black cells 104 in a matrix. The two-dimensional matrix code 100 is provided on a side surface of a laminate 108 without being tilted relative to the stacking direction (see the Z axis in FIG. 3A) in which multiple steel plates 106 are stacked. Here, the size of each white cell 102 and each black cell 104 is smaller than the thickness of a steel plate 106. For example, if the black cells 104 constituting the clock pattern of the two-dimensional matrix code 100 are formed so as to connect with the boundaries 110 between adjacent steel plates 106 (see the area surrounded by the dashed line indicated by arrow B in FIG. 3A), the width of the black cells 104 may not be read correctly, causing the grid to fluctuate when the cells are divided, which may result in an incorrect reading of the clock pattern. Furthermore, for example, if the boundary 110 between adjacent steel plates 106 is located along the boundary between the quiet zone and the clock pattern (see the area surrounded by the dashed line indicated by arrow C in Figure 3A), the quiet zone and clock pattern may not be read correctly, resulting in a reading error of the 2D matrix code 100.

[0044] In contrast, as shown in FIG. 3B , the two-dimensional matrix code 38 according to this embodiment is configured by arranging white cells 46 and black cells 48 in a matrix. The two-dimensional matrix code 38 is provided on the side surface of the laminate 36 in a state inclined with respect to the stacking direction (see the Z axis in FIG. 3B ) in which the steel plates 40 are stacked. When viewed from the radial direction, the two-dimensional matrix code 38 is inclined with respect to the stacking direction in which the steel plates 40 are stacked. The inclination angle of the two-dimensional matrix code 38 with respect to the stacking direction in which the steel plates 40 are stacked is preferably 30 degrees or more and 60 degrees or less. Specifically, as an example, the inclination angle of the two-dimensional matrix code 38 with respect to the stacking direction in which the steel plates 40 are stacked is 45 degrees. Because the two-dimensional matrix code 38 is inclined with respect to the stacking direction in which the steel plates 40 are stacked, each side of the white cells 46 and each side of the black cells 48 is inclined with respect to the stacking direction in which the steel plates 40 are stacked. Here, the size of one white cell 46 and the size of one black cell 48 are smaller than the thickness of the steel plate 40. Because the two-dimensional matrix code 38 is tilted with respect to the stacking direction in which the multiple steel plates 40 are stacked, the black cells 48 are tilted with respect to the stacking direction in which the multiple steel plates 40 are stacked, preventing the black cells 48 from connecting with the borders 50 and preventing the width of the black cells 48 from being read correctly. Furthermore, the borders between the quiet zones and the clock patterns are tilted with respect to the stacking direction in which the multiple steel plates 40 are stacked. Therefore, the borders 50 are prevented from being located along the borders between the quiet zones and the clock patterns, preventing the quiet zones and the clock patterns from being read correctly. This prevents the occurrence of reading errors in the two-dimensional matrix code 38.

[0045] As described above, by tilting the two-dimensional matrix code 38 with respect to the stacking direction in which the steel plates 40 are stacked, it is possible to prevent a decrease in the readability of the two-dimensional matrix code 38 and to prevent reading errors from occurring.

[0046] Next, we will explain the experimental results of the readability of 2D matrix codes at each tilt angle. Here, the experiment was conducted with a steel plate thickness of 0.5 mm and a side length of one cell that makes up the 2D matrix code of 0.3 mm.

[0047] 4A to 4F are diagrams showing two-dimensional matrix codes with different tilt angles. FIG. 4A is a diagram showing a two-dimensional matrix code when the tilt angle with respect to the stacking direction is 0 degrees. FIG. 4B is a diagram showing a two-dimensional matrix code when the tilt angle with respect to the stacking direction is 5 degrees. FIG. 4C is a diagram showing a two-dimensional matrix code when the tilt angle with respect to the stacking direction is 10 degrees. FIG. 4D is a diagram showing a two-dimensional matrix code when the tilt angle with respect to the stacking direction is 15 degrees. FIG. 4E is a diagram showing a two-dimensional matrix code when the tilt angle with respect to the stacking direction is 30 degrees. FIG. 4F is a diagram showing a two-dimensional matrix code when the tilt angle with respect to the stacking direction is 45 degrees. In FIGS. 4A to 4F, unit cells surrounded by squares indicate unit cells in which reading errors have occurred.

[0048] FIG. 5 is a graph showing the readability at each tilt angle in FIGS. 4A to 4F.

[0049] In the graph shown in Figure 5, modulation degree is an index showing the readability of each unit cell that makes up the two-dimensional matrix code. Modulation degree indicates how easily it is possible to distinguish between a white cell and a black cell for each unit cell that makes up the two-dimensional matrix code. For example, modulation degree indicates how much margin there is between the value for distinguishing whether a unit cell is white or black, obtained for that unit cell, and the threshold value for distinguishing whether the cell is white or black. The larger this margin, the easier it is to distinguish whether the cell is white or black, and the higher the grade of modulation.

[0050] In the graph shown in Figure 5, fixed pattern damage is an index that indicates the readability of the quiet zone, clock pattern, and alignment pattern that make up the 2D matrix code. Fixed pattern damage indicates the ease of distinguishing the quiet zone, clock pattern, and alignment pattern. For example, for each unit cell that makes up the 2D matrix code, a value used to distinguish between a white cell and a black cell is read, and the arrangement of these values ​​determines the arrangement of white and black cells, allowing the quiet zone, clock pattern, and alignment pattern to be distinguished. The greater the margin of these values ​​relative to the threshold for distinguishing between white and black cells, the easier it is to distinguish the quiet zone, clock pattern, and alignment pattern, and the higher the grade of fixed pattern damage.

[0051] For example, as shown in FIG. 4A, when the tilt angle of the two-dimensional matrix code with respect to the stacking direction is 0 degrees, the modulation degree and fixed pattern damage grade are 0. When the tilt angle of the two-dimensional matrix code with respect to the stacking direction is 5 degrees, 10 degrees, and 15 degrees, the modulation degree grade is 0 and the fixed pattern damage grade is 2. When the tilt angle of the two-dimensional matrix code with respect to the stacking direction is 30 degrees, the modulation degree grade is 1 and the fixed pattern damage grade is 2. When the tilt angle of the two-dimensional matrix code with respect to the stacking direction is 45 degrees, the modulation degree grade is 2 and the fixed pattern damage grade is 3.

[0052] By increasing the tilt angle of the 2D matrix code to 5 degrees relative to the lamination direction, the grade of fixed pattern damage increases, and the readability of the quiet zone, clock pattern, and alignment pattern improves. On the other hand, the grade of modulation remains unchanged, and the readability of each unit cell that makes up the 2D matrix code remains unchanged.

[0053] When the inclination angle of the two-dimensional matrix code with respect to the lamination direction is set to 10 degrees or 15 degrees, the results are substantially the same as when it is set to 5 degrees.

[0054] By setting the inclination angle of the 2D matrix code to the lamination direction at 30 degrees, the grades of both the modulation depth and the fixed pattern damage are improved. It can be seen that the readability of each unit cell that makes up the 2D matrix code, as well as the readability of the quiet zone, clock pattern, and alignment pattern, are all improved.

[0055] By tilting the 2D matrix code at a 45-degree angle relative to the lamination direction, the grades of both the modulation depth and fixed pattern damage are further improved. It can be seen that the readability of each unit cell that makes up the 2D matrix code, as well as the readability of the quiet zone, clock pattern, and alignment pattern, are all further improved.

[0056] Although not shown in the figure, the inclination angle of the 2D matrix code with respect to the stacking direction is thought to have detection characteristics that are line-symmetric with 45 degrees as the center. Therefore, when the inclination angle of the 2D matrix code with respect to the stacking direction is set to 60 degrees, it is thought that the same tendency will be observed as when it is set to 30 degrees.

[0057] As described above, when the inclination angle of the 2D matrix code with respect to the stacking direction is between 30 degrees and 60 degrees, the readability of the 2D matrix code is higher and the occurrence of reading errors can be reduced compared to when the inclination angle is between 0 degrees and less than 30 degrees. When the inclination angle of the 2D matrix code with respect to the stacking direction is 45 degrees, the readability of the 2D matrix code is the highest and the occurrence of reading errors can be further reduced.

[0058] The laminated core 30 according to the embodiment and the electric motor 10 including the same have been described above.

[0059] The laminated core 30 according to the embodiment includes a laminate 36 formed by stacking a plurality of steel plates 40, and a two-dimensional matrix code 38 provided on the side of the laminate 36, and the two-dimensional matrix code 38 is inclined with respect to the stacking direction in which the plurality of steel plates 40 are stacked.

[0060] According to this, the two-dimensional matrix code 38 is provided on the side surface of the laminate 36. This prevents the two-dimensional matrix code 38 from being obscured by other components, etc., and reduces the readability of the two-dimensional matrix code 38. Furthermore, the two-dimensional matrix code 38 is inclined with respect to the stacking direction in which the multiple steel plates 40 are stacked. This prevents the boundaries 50 located between adjacent steel plates 40 among the multiple steel plates 40 from becoming parallel to the row and column directions of the two-dimensional matrix code 38. This prevents the readability from being reduced due to the boundaries 50 connecting with at least one of the white cells 46 and the black cells 48 that make up the two-dimensional matrix code 38, and reduces the occurrence of reading errors of the two-dimensional matrix code 38.

[0061] In the laminated core 30 according to the embodiment, the inclination angle of the two-dimensional matrix code 38 with respect to the lamination direction is equal to or greater than 30 degrees and equal to or less than 60 degrees.

[0062] This can further prevent degradation in the readability of each unit cell that constitutes the two-dimensional matrix code 38, that is, the white cells 46 and the black cells 48, and can further prevent reading errors from occurring in the two-dimensional matrix code 38.

[0063] In the laminated core 30 according to the embodiment, the inclination angle of the two-dimensional matrix code 38 with respect to the lamination direction is 45 degrees.

[0064] This makes it possible to further suppress the deterioration of the readability of each unit cell that constitutes the two-dimensional matrix code 38, i.e., the white cells 46 and the black cells 48, compared to when the inclination angle is 30 degrees, etc., and further suppress the occurrence of reading errors in the two-dimensional matrix code 38.

[0065] In the laminated core 30 according to the embodiment, the two-dimensional matrix code 38 is a DMC.

[0066] According to this, by tilting the two-dimensional matrix code 38 with respect to the stacking direction, it is possible to suppress deterioration in the readability of the quiet zone, clock pattern, and alignment pattern, and therefore to suppress occurrence of DMC reading failure.

[0067] Moreover, the electric motor 10 according to the embodiment includes the laminated core 30 described above.

[0068] This makes it possible to obtain the electric motor 10 that can suppress the occurrence of reading errors of the two-dimensional matrix code 38.

[0069] Moreover, the electric motor 10 according to the embodiment further includes a winding 32 wound around the laminated core 30 .

[0070] This prevents the two-dimensional matrix code 38 from being hidden by the winding 32 even when the winding 32 is wound around the laminated core 30. Therefore, the readability of the two-dimensional matrix code 38 can be prevented from being reduced.

[0071] (Other embodiments, etc.) The laminated core 30 according to the present disclosure and the electric motor 10 including the laminated core 30 have been described above based on the embodiments. However, the present disclosure is not limited to the above-described embodiments.

[0072] In the above-described embodiment, the laminated core 30 is a rotor core around which windings 32 are wound. However, this is not limiting. For example, the laminated core may be a rotor core without windings, a stator core with windings wound around it, or a stator core without windings wound around it. In other words, the laminated core may or may not be an armature core.

[0073] In the above-described embodiment, the stator 14 does not have a laminated core. However, this is not limiting. For example, the stator may have a laminated core. In this case, a two-dimensional matrix code may be provided on the side surface of the laminated core.

[0074] In the above-described embodiment, the electric motor 10 is an inner rotor motor in which the rotor 16 is disposed inside the stator 14. However, the present invention is not limited to this. For example, the electric motor may be an outer rotor motor in which the rotor is disposed outside the stator. In this case, a two-dimensional matrix code may be provided on the side surface of the laminated core of the stator, or a two-dimensional matrix code may be provided on the side surface of the laminated core of the rotor.

[0075] In the above-described embodiment, the two-dimensional matrix code 38 is provided on the outer surface of the laminate 36. However, this is not limiting. For example, the two-dimensional matrix code may be provided on the inner surface of the laminate.

[0076] In the above-described embodiment, the two-dimensional matrix code 38 is a DMC. However, this is not limiting. For example, the two-dimensional matrix code may be a QR Code (registered trademark) or a Veri Code, or may be any of various two-dimensional matrix codes in which white cells and black cells are arranged in rows and columns.

[0077] In the above-described embodiment, the size of the white cells 46 and the size of the black cells 48 that make up the two-dimensional matrix code 38 are smaller than the thickness of the steel plate 40. However, this is not limiting. For example, the size of the white cells and the size of the black cells that make up the two-dimensional matrix code may be equal to the thickness of the steel plate, or may be larger than the thickness of the steel plate.

[0078] In the above-described embodiment, a case has been described in which one two-dimensional matrix code 38 is provided on the laminate 36. However, this is not limiting. For example, a plurality of two-dimensional matrix codes may be provided on the laminate. In this case, for example, the inclination angle with respect to the stacking direction in which the plurality of steel plates are stacked may be different for each two-dimensional matrix code. Furthermore, the code size may be different for each two-dimensional matrix code.

[0079] In the above-described embodiment, the two-dimensional matrix code 38 is printed using a laser or the like. However, this is not limiting. For example, the two-dimensional matrix code may be printed using an inkjet or the like.

[0080] In addition, this disclosure also includes forms obtained by applying various modifications to the above embodiments that a person skilled in the art would think of, or forms realized by arbitrarily combining the components and functions of each embodiment within the scope of this disclosure. [Industrial Applicability]

[0081] The technology of the present disclosure can be widely used in laminated stator cores and laminated rotor cores in electric motors. Furthermore, the technology of the present disclosure can be widely used not only in stators and rotors, but also in electric motors including stators and rotors, and various electrical devices including such electric motors. Alternatively, the technology can be used in cores, etc., that are made by laminating steel sheets and are used in transformers. [Explanation of symbols]

[0082] 10 Electric motor 12 frames 13,26 bearing 14 Stator 16 rotors 18 Commutator 20 brushes 22 Brush holder 24 Seal ring 28 Permanent Magnets 30 Laminated core 32 windings 34 Rotation axis 36 Laminate 38 2D matrix code 40 steel plate 42 Teeth 44 Commutator piece 46 White Cells 48 Black Cells 50 Boundary

Claims

1. a laminate formed by stacking a plurality of steel plates; a two-dimensional matrix code provided on a side surface of the laminate; the two-dimensional matrix code is inclined with respect to the stacking direction in which the plurality of steel plates are stacked; Laminated iron core.

2. an inclination angle of the two-dimensional matrix code with respect to the stacking direction is equal to or greater than 30 degrees and equal to or less than 60 degrees; The laminated core according to claim 1 .

3. The tilt angle is 45 degrees. The laminated core according to claim 2 .

4. The two-dimensional matrix code is a Data Matrix Code. The laminated core according to any one of claims 1 to 3.

5. A laminated core according to any one of claims 1 to 4, Electric motor.

6. Further comprising a winding wound around the laminated core.

6. The electric motor according to claim 5.

Images