Invention title: Laminated core and rotary electric machine
Technical field
[0001]
　The present invention relates to a laminated core and a rotary electric machine.
　The present application claims priority based on Japanese Patent Application No. 2018-235866 filed in Japan on December 17, 2018, the contents of which are incorporated herein by reference.
Background technology
[0002]
　Conventionally, a laminated core as described in Patent Document 1 below has been known. In this laminated core, electromagnetic steel sheets adjacent to each other in the laminated direction are joined by both bonding and caulking methods.
Prior art literature
Patent documents
[0003]
Patent Document 1: Japanese Patent Application Laid-Open No. 2015-136228
Outline of the invention
Problems to be solved by the invention
[0004]
　There is room for improvement in improving the magnetic characteristics of the conventional laminated core while ensuring the dimensional accuracy of the outer shape.
[0005]
　The present invention has been made in view of the above circumstances, and an object of the present invention is to improve magnetic characteristics while ensuring dimensional accuracy of the outer shape.
Means to solve problems
[0006]
　In order to solve the above problems, the present invention proposes the following means.
(1) The first aspect of the present invention is a laminated core in which a plurality of electromagnetic steel sheets laminated to each other are provided, and all sets of electromagnetic steel sheets adjacent to each other in the stacking direction are fixed to each other. Of the electrical steel sheets, some sets of electrical steel sheets are not crimped and bonded, and the remaining sets of electrical steel sheets are laminated cores that are not crimped to each other.
[0007]
　Joining by caulking can improve dimensional accuracy as compared with joining by bonding. Here, of all the sets of electromagnetic steel sheets adjacent to each other in the stacking direction, some sets of electromagnetic steel sheets are crimped to each other. Therefore, it is possible to improve the accuracy of the shape of the portion of the laminated core formed by some of these sets. As a result, the accuracy of the outer shape of the laminated core can be improved. Therefore, the handleability of the laminated core can be ensured. For example, even when winding the winding around the laminated core, it can be wound with high accuracy.
　However, joining by caulking may generate a short-circuit current (stray current) between adjacent electromagnetic steel sheets in the stacking direction. Here, of all the sets of electromagnetic steel sheets adjacent to each other in the laminating direction, the remaining sets of electromagnetic steel sheets other than the above-mentioned set are bonded to each other. Therefore, the generation of stray current can be suppressed between these remaining sets of electrical steel sheets. As a result, the magnetic properties of the laminated core can be improved.
[0008]
(2) In the laminated core according to the above (1), the plurality of electromagnetic steel sheets may be bonded to every other set or more in the laminated direction.
[0009]
　A plurality of electrical steel sheets are bonded to each other in one or more sets in the stacking direction. Therefore, it is possible to prevent the electromagnetic steel sheets joined by adhesion from being locally concentrated on a part of the laminated core in the laminated direction. In other words, the electromagnetic steel sheets joined by adhesion can be dispersed in the stacking direction. As a result, the accuracy of the outer shape of the laminated core can be further improved.
[0010]
(3) In the laminated core according to the above (1) or (2), the plurality of electromagnetic steel sheets may be bonded in every prime number set in the lamination direction.
[0011]
　The laminated core also has a unique resonance frequency like a general article. If the resonance frequency of the laminated core is low, resonance is likely to occur when general vibration is input. Therefore, it is preferable that the resonance frequency of the laminated core is high.
　Here, when a plurality of electrical steel sheets are bonded every N pairs in the stacking direction, the resonance frequency of the laminated core tends to depend on N.
　That is, in the case of bonding every N sets, (N + 1) sheets of electrical steel sheets are arranged between the bonded portions adjacent to each other in the stacking direction, and these electrical steel sheets are crimped to each other. When the bonding strength due to the bonded portion is lower than the bonding strength due to caulking, the (N + 1) sheets of electromagnetic steel sheets tend to behave integrally with the bonded portion as the starting point. In other words, the (N + 1) sheets of electrical steel sheets behave as if they were one block. In such a laminated core, when a plurality of electrical steel sheets are bonded at equal intervals in the stacking direction every N pairs, the resonance frequency of the laminated core is affected by a divisor of N. Further, when a plurality of electrical steel sheets are adhered to N1 sets, N2 sets, ... The larger the divisor or the least common multiple, the higher the resonance frequency of the laminated core.
　A plurality of electrical steel sheets are bonded to each other in the stacking direction in every prime number set. Therefore, even when a plurality of electrical steel sheets are bonded to every N pairs (however, N is a prime number) at equal intervals in the stacking direction, N is a prime number and the above divisor is increased. be able to. Further, even when a plurality of electrical steel sheets are bonded to N1 sets, N2 sets, ..., Which are different from each other in the stacking direction, the least common multiple for N1, N2 ... Can be increased. Therefore, the resonance frequency of the laminated core can be increased. As a result, for example, the resonance frequency can be set to a frequency higher than the audible range. Thereby, for example, even when this laminated core is applied to an electric motor, it is possible to suppress the generation of noise due to resonance.
[0012]
(4) In the laminated core according to any one of (1) to (3), the plurality of electromagnetic steel sheets have a mixture of portions bonded to each other in different number of sets in the laminated direction. May be good.
[0013]
　In a plurality of electrical steel sheets, there are a mixture of parts that are bonded to each other in different number of sets in the stacking direction. Therefore, when it is assumed that a plurality of electrical steel sheets are adhered to N1 sets, N2 sets, ... Therefore, the resonant frequency of the stacked cores can be increased according to the least common multiple of their number of pairs. As a result, the generation of noise due to resonance can be further suppressed.
　It should be noted that such an action effect is remarkably effective when the prime numbers are bonded to each other in the stacking direction. That is, in this case, the least common multiple can be increased.
[0014]
(5) In the laminated core according to any one of (1) to (4), the electromagnetic steel sheet protrudes from the annular core back portion and the core back portion in the radial direction of the core back portion. In addition, a plurality of teeth portions arranged at intervals in the circumferential direction of the core back portion may be provided.
[0015]
　The laminated core is a stator core including a core back portion and a teeth portion. Therefore, for example, when the winding is passed through the slots between the teeth portions adjacent to each other in the circumferential direction, the above-mentioned action and effect of ensuring the handleability is remarkably achieved. That is, if the dimensional accuracy of the slot is improved, it is possible to easily wind the winding around the teeth portion as designed. As a result, the winding space factor in the slot can be increased. As a result, the electrical load in the slot can be increased.
[0016]
(6) In the laminated core according to any one of (1) to (5), the average thickness of the bonded portion may be 1.0 μm to 3.0 μm.
[0017]
(7) In the laminated core according to any one of (1) to (6) above, the average tensile elastic modulus E of the bonded portion may be 1500 MPa to 4500 MPa.
[0018]
(8) In the laminated core according to any one of (1) to (7) above, the adhesive portion is a room temperature adhesive type acrylic adhesive containing SGA made of an elastomer-containing acrylic adhesive. You may.
[0019]
(9) The second aspect of the present invention includes the laminated core according to any one of the above (1) to (8).
The invention's effect
[0020]
　According to the present invention, it is possible to improve the magnetic characteristics while ensuring the dimensional accuracy of the outer shape.
A brief description of the drawing
[0021]
FIG. 1 is a cross-sectional view of a rotary electric machine according to an embodiment of the present invention.
FIG. 2 is a plan view of a stator included in the rotary electric machine shown in FIG.
FIG. 3 is a side view of a stator included in the rotary electric machine shown in FIG.
FIG. 4 is a plan view of an electromagnetic steel plate and an adhesive portion of a stator included in the rotary electric machine shown in FIG.
5 is a plan view of an electromagnetic steel plate and caulking of a stator included in the rotary electric machine shown in FIG. 1. FIG.
FIG. 6 is a cross-sectional view taken along the line VI-VI shown in FIG.
FIG. 7 is a side view of a stator included in the first modification of the rotary electric machine shown in FIG.
8 is a cross-sectional view of the stator shown in FIG. 7, which is a cross-sectional view corresponding to FIG.
9 is a side view of the stator included in the second modification of the rotary electric machine shown in FIG. 1. FIG.
FIG. 10 is a side view of a stator included in a third modification of the rotary electric machine shown in FIG.
Mode for carrying out the invention
[0022]
　Hereinafter, the rotary electric machine according to the embodiment of the present invention will be described with reference to the drawings. In the present embodiment, an electric motor as a rotary electric machine, specifically an AC electric motor, more specifically a synchronous electric motor, and even more specifically, a permanent magnet field type electric motor will be described as an example. This type of motor is suitably adopted for, for example, an electric vehicle.
[0023]
　As shown in FIGS. 1 and 2, the rotary electric machine 10 includes a stator 20, a rotor 30, a case 50, and a rotary shaft 60. The stator 20 and rotor 30 are housed in a case 50. The stator 20 is fixed to the case 50.
　In the present embodiment, as the rotary electric machine 10, an inner rotor type in which the rotor 30 is located inside the stator 20 is adopted. However, as the rotary electric machine 10, an outer rotor type in which the rotor 30 is located outside the stator 20 may be adopted. Further, in the present embodiment, the rotary electric machine 10 is a 12-pole 18-slot three-phase AC motor. However, for example, the number of poles, the number of slots, the number of phases, and the like can be changed as appropriate. The rotary electric machine 10 can rotate at a rotation speed of 1000 rpm by applying an exciting current having an effective value of 10 A and a frequency of 100 Hz to each phase, for example.
[0024]
　The stator 20 includes a stator core 21 and a winding (not shown).
　The stator core 21 includes an annular core back portion 22 and a plurality of teeth portions 23. In the following, the axial direction of the stator core 21 (core back portion 22) (the central axis O direction of the stator core 21) is referred to as the axial direction, and the radial direction of the stator core 21 (core back portion 22) (orthogonal to the central axis O of the stator core 21). The direction) is called the radial direction, and the circumferential direction of the stator core 21 (core back portion 22) (the direction that orbits around the central axis O of the stator core 21) is called the circumferential direction.
[0025]
　The core back portion 22 is formed in an annular shape in a plan view of the stator 20 when viewed from the axial direction.
　The plurality of tooth portions 23 project from the core back portion 22 inward in the radial direction (toward the central axis O of the core back portion 22 along the radial direction). The plurality of tooth portions 23 are arranged at equal intervals in the circumferential direction. In the present embodiment, 18 tooth portions 23 are provided at every 20 degrees of the central angle centered on the central axis O. The plurality of tooth portions 23 are formed to have the same shape and the same size as each other. For example, for the purpose of reducing cogging torque, the shapes and sizes of the plurality of teeth portions 23 may not be the same.
　The winding is wound around the teeth portion 23. The winding may be a centralized winding or a distributed winding.
[0026]
　The rotor 30 is arranged inside the stator 20 (stator core 21) in the radial direction. The rotor 30 includes a rotor core 31 and a plurality of permanent magnets 32.
　The rotor core 31 is formed in an annular shape (annular ring) arranged coaxially with the stator 20. The rotating shaft 60 is arranged in the rotor core 31. The rotating shaft 60 is fixed to the rotor core 31.
　The plurality of permanent magnets 32 are fixed to the rotor core 31. In this embodiment, a set of two permanent magnets 32 form one magnetic pole. The plurality of sets of permanent magnets 32 are arranged at equal intervals in the circumferential direction. In the present embodiment, 12 sets (24 in total) of permanent magnets 32 are provided at a central angle of 30 degrees about the central axis O. For example, for the purpose of reducing cogging torque, the intervals between the plurality of sets of permanent magnets 32 do not have to be the same.
[0027]
　In this embodiment, an embedded magnet type motor is adopted as a permanent magnet field type motor. The rotor core 31 is formed with a plurality of through holes 33 that penetrate the rotor core 31 in the axial direction. The plurality of through holes 33 are provided corresponding to the plurality of permanent magnets 32. Each permanent magnet 32 ​​is fixed to the rotor core 31 in a state of being arranged in the corresponding through hole 33. Fixing of each permanent magnet 32 ​​to the rotor core 31 can be realized, for example, by adhering the outer surface of the permanent magnet 32 ​​and the inner surface of the through hole 33 with an adhesive or the like. As the permanent magnet field type motor, a surface magnet type motor may be adopted instead of the embedded magnet type motor.
[0028]
　Both the stator core 21 and the rotor core 31 are laminated cores. The laminated core is formed by laminating a plurality of electromagnetic steel sheets 40.
　The product thickness of each of the stator core 21 and the rotor core 31 is, for example, 50.0 mm. The outer diameter of the stator core 21 is, for example, 250.0 mm. The inner diameter of the stator core 21 is, for example, 165.0 mm. The outer diameter of the rotor core 31 is, for example, 163.0 mm. The inner diameter of the rotor core 31 is, for example, 30.0 mm. However, these values ​​are examples, and the product thickness, outer diameter and inner diameter of the stator core 21, and the product thickness, outer diameter and inner diameter of the rotor core 31 are not limited to these values. Here, the inner diameter of the stator core 21 is based on the tip of the teeth portion 23 of the stator core 21. The inner diameter of the stator core 21 is the diameter of a virtual circle inscribed in the tips of all the teeth portions 23.
[0029]
　Each of the electromagnetic steel sheets 40 forming the stator core 21 and the rotor core 31 is formed, for example, by punching an electromagnetic steel sheet as a base material. As the electromagnetic steel sheet 40, a known electrical steel sheet can be used. The chemical composition of the electrical steel sheet 40 is not particularly limited. In this embodiment, a non-oriented electrical steel sheet is used as the electrical steel sheet 40. As the non-oriented electrical steel sheet, for example, a non-oriented electrical steel strip of JIS C 2552: 2014 can be adopted. However, as the electromagnetic steel sheet 40, it is also possible to use a grain-oriented electrical steel sheet instead of the non-oriented electrical steel sheet. As the grain-oriented electrical steel sheet, for example, a grain-oriented electrical steel strip of JIS C 2553: 2012 can be adopted.
[0030]
　Insulating coatings are provided on both sides of the electrical steel sheet 40 in order to improve the workability of the electrical steel sheet and the iron loss of the laminated core. As the substance constituting the insulating film, for example, (1) an inorganic compound, (2) an organic resin, (3) a mixture of an inorganic compound and an organic resin, and the like can be applied. Examples of the inorganic compound include (1) a complex of dichromate and boric acid, and (2) a complex of phosphate and silica. Examples of the organic resin include epoxy-based resin, acrylic-based resin, acrylic-styrene-based resin, polyester-based resin, silicon-based resin, and fluorine-based resin.
[0031]
　In order to ensure the insulating performance between the electromagnetic steel sheets 40 laminated with each other, the thickness of the insulating film (thickness per one side of the electromagnetic steel sheets 40) is preferably 0.1 μm or more.
　On the other hand, the insulating effect is saturated as the insulating film becomes thicker. Further, as the insulating film becomes thicker, the space factor decreases, and the performance as a laminated core deteriorates. Therefore, the insulating coating should be as thin as possible to ensure the insulating performance. The thickness of the insulating film (thickness per one side of the electromagnetic steel sheet 40) is preferably 0.1 μm or more and 5 μm or less, and more preferably 0.1 μm or more and 2 μm or less.
[0032]
　As the electromagnetic steel sheet 40 becomes thinner, the effect of improving iron loss gradually saturates. Further, as the electromagnetic steel sheet 40 becomes thinner, the manufacturing cost of the electrical steel sheet 40 increases. Therefore, the thickness of the electrical steel sheet 40 is preferably 0.10 mm or more in consideration of the effect of improving iron loss and the manufacturing cost.
　On the other hand, if the electromagnetic steel sheet 40 is too thick, the press punching operation of the electrical steel sheet 40 becomes difficult. Therefore, considering the press punching work of the electrical steel sheet 40, the thickness of the electrical steel sheet 40 is preferably 0.65 mm or less.
　Further, as the electromagnetic steel sheet 40 becomes thicker, the iron loss increases. Therefore, considering the iron loss characteristics of the electrical steel sheet 40, the thickness of the electrical steel sheet 40 is preferably 0.35 mm or less, more preferably 0.20 mm or 0.25 mm.
　In consideration of the above points, the thickness of each electrical steel sheet 40 is, for example, 0.10 mm or more and 0.65 mm or less, preferably 0.10 mm or more and 0.35 mm or less, more preferably 0.20 mm or 0.25 mm. be. The thickness of the electrical steel sheet 40 includes the thickness of the insulating coating.
[0033]
　A part of the plurality of electromagnetic steel sheets 40 forming the stator core 21 is adhered by the adhesive portion 41. The adhesive portion 41 is an adhesive that is provided between the electromagnetic steel sheets 40 that are adjacent to each other in the stacking direction and is cured without being divided. As the adhesive, for example, a thermosetting adhesive by polymerization bonding is used. As the composition of the adhesive, (1) an acrylic resin, (2) an epoxy resin, (3) a composition containing an acrylic resin and an epoxy resin, and the like can be applied. As such an adhesive, a radical polymerization type adhesive or the like can be used in addition to a thermosetting type adhesive, and from the viewpoint of productivity, it is desirable to use a room temperature curing type adhesive. The room temperature curable adhesive cures at 20 ° C to 30 ° C. As the room temperature curing type adhesive, an acrylic adhesive is preferable. Typical acrylic adhesives include SGA (Second Generation Acrylic Adhesives. Second Generation Acrylic Adhesive) and the like. An anaerobic adhesive, an instant adhesive, and an elastomer-containing acrylic adhesive can be used as long as the effects of the present invention are not impaired. The adhesive referred to here refers to a state before curing, and becomes an adhesive portion 41 after the adhesive is cured.
[0034]
　The average tensile elastic modulus E of the bonded portion 41 at room temperature (20 ° C. to 30 ° C.) is in the range of 1500 MPa to 4500 MPa. If the average tensile elastic modulus E of the bonded portion 41 is less than 1500 MPa, there will be a problem that the rigidity of the laminated core is lowered. Therefore, the lower limit of the average tensile elastic modulus E of the adhesive portion 41 is 1500 MPa, more preferably 1800 MPa. On the contrary, if the average tensile elastic modulus E of the adhesive portion 41 exceeds 4500 MPa, a problem occurs in which the insulating film formed on the surface of the electromagnetic steel sheet 40 is peeled off. Therefore, the upper limit of the average tensile elastic modulus E of the adhesive portion 41 is 4500 MPa, more preferably 3650 MPa.
　The average tensile elastic modulus E is measured by the resonance method. Specifically, the tensile elastic modulus is measured in accordance with JIS R 1602: 1995.
　More specifically, first, a sample for measurement (not shown) is produced. This sample is obtained by adhering two electromagnetic steel sheets 40 together with an adhesive to be measured and curing them to form an adhesive portion 41. When the adhesive is a thermosetting type, this curing is performed by heating and pressurizing under the heating and pressurizing conditions in actual operation. On the other hand, when the adhesive is a room temperature curing type, it is performed by pressurizing at room temperature.
　Then, the tensile elastic modulus of this sample is measured by the resonance method. As described above, the method for measuring the tensile elastic modulus by the resonance method is performed in accordance with JIS R 1602: 1995. After that, the tensile elastic modulus of the bonded portion 41 alone can be obtained by removing the influence of the electromagnetic steel sheet 40 itself from the tensile elastic modulus (measured value) of the sample by calculation.
　Since the tensile elastic modulus obtained from the sample in this way is equal to the average value of the entire laminated core, this value is regarded as the average tensile elastic modulus E. The composition of the average tensile elastic modulus E is set so that it hardly changes at the stacking position along the stacking direction or at the circumferential position around the central axis of the laminated core. Therefore, the average tensile elastic modulus E can be set to a value obtained by measuring the cured bonded portion 41 at the upper end position of the laminated core.
[0035]
　As the bonding method, for example, a method of applying an adhesive to the electromagnetic steel sheet 40 and then bonding by heating and / or pressure bonding can be adopted. The heating means may be any means such as heating in a high temperature bath or an electric furnace, or a method of directly energizing.
[0036]
　In order to obtain stable and sufficient adhesive strength, the thickness of the adhesive portion 41 is preferably 1 μm or more.
　On the other hand, when the thickness of the adhesive portion 41 exceeds 100 μm, the adhesive force is saturated. Further, as the adhesive portion 41 becomes thicker, the space factor decreases, and the torque density when the laminated core is used as a motor decreases. Therefore, the thickness of the adhesive portion 41 is preferably 1 μm or more and 100 μm or less, more preferably 1 μm or more and 10 μm or less.
　In the above, the thickness of the adhesive portion 41 means the average thickness of the adhesive portion 41.
[0037]
　The average thickness of the bonded portion 41 is more preferably 1.0 μm or more and 3.0 μm or less. If the average thickness of the adhesive portion 41 is less than 1.0 μm, sufficient adhesive strength cannot be secured as described above. Therefore, the lower limit of the average thickness of the adhesive portion 41 is 1.0 μm, more preferably 1.2 μm. On the contrary, if the average thickness of the bonded portion 41 becomes thicker than 3.0 μm, problems such as a large increase in the amount of strain of the electromagnetic steel sheet 40 due to shrinkage during thermosetting occur. Therefore, the upper limit of the average thickness of the adhesive portion 41 is 3.0 μm, more preferably 2.6 μm.
　The average thickness of the bonded portion 41 is an average value of the laminated core as a whole. The average thickness of the adhesive portion 41 is almost the same at the stacking position along the stacking direction and the circumferential position around the central axis of the laminated core. Therefore, the average thickness of the adhesive portion 41 can be set as the average value of the numerical values ​​measured at 10 or more points in the circumferential direction at the upper end position of the laminated core.
[0038]
　The average thickness of the adhesive portion 41 can be adjusted by changing, for example, the amount of the adhesive applied. Further, the average tensile elastic modulus E of the adhesive portion 41 is adjusted, for example, in the case of a thermosetting type adhesive by changing one or both of the heating and pressurizing conditions applied at the time of adhesion and the type of curing agent. Can be done.
[0039]
　In this embodiment, the plurality of electromagnetic steel sheets 40 forming the rotor core 31 are fixed to each other by caulking C (dowels). However, a plurality of electrical steel sheets 40 forming the rotor core 31 may be bonded to each other by the bonding portion 41.
　The laminated cores such as the stator core 21 and the rotor core 31 may be formed by so-called rotating stacking.
[0040]
　Here, as shown in FIGS. 3 and 4, in the stator core 21 of the present embodiment, all the pairs of the electromagnetic steel sheets 40 adjacent to each other in the stacking direction are fixed by either adhesion or caulking. Of all the sets of electrical steel sheets 40, some sets of electrical steel sheets 40 are not crimped and bonded, and the remaining sets of electrical steel sheets 40 are not bonded to each other.
[0041]
　In the present embodiment, the plurality of electromagnetic steel sheets 40 are arranged in one or more sets in the stacking direction, specifically every other set of prime numbers (at least in the present specification, the prime number includes 1), and more specifically every other set. It is glued. In other words, when a plurality of electrical steel sheets 40 are bonded to each other in N layers in the stacking direction, N is a natural number, specifically N is a prime number, and more specifically N is 1. That is, the plurality of electromagnetic steel sheets 40 are bonded to every other set in the stacking direction and crimped to every other set. In other words, the plurality of electrical steel sheets 40 are alternately joined by caulking and bonding along the laminating direction. That is, as shown in FIG. 3, the adhesive portions 41 are not arranged between all the sets, but are arranged every other set. Further, in the electromagnetic steel sheet 40 sandwiched between the pair of electromagnetic steel sheets 40 in the stacking direction, one of the pair of electrical steel sheets 40 is crimped and the other is bonded.
　Here, the fact that a plurality of electromagnetic steel sheets 40 are bonded every N pairs in the stacking direction means that N pairs (N + 1) of electrical steel sheets are bonded between a pair of bonding portions 41 arranged apart from each other in the stacking direction. It means that 40 is arranged. When N is 1, one set (two pieces) of electrical steel sheets 40 are arranged between the pair of adhesive portions 41, and when N is 2, two sets (3) are arranged between the pair of adhesive portions 41. Sheets) electromagnetic steel sheets 40 are arranged.
[0042]
　The present invention is not limited to this, and a plurality of electromagnetic steel sheets 40 are arranged in two sets (every three sheets) in the stacking direction, as in the stators 20A and 20B according to the modified examples shown in FIGS. 7 and 8 and FIG. ) Or every 3 sets (every 4 sheets) may be adhered. In other words, the adhesive portions 41 may be provided every two or three sets in the stacking direction. In these cases, the unbonded electrical steel sheets 40 are crimped to each other. As a result, among all the sets of the electromagnetic steel sheets 40, the number of sets of the electromagnetic steel sheets 40 joined by caulking is larger than the number of sets of the electromagnetic steel sheets 40 joined by adhesion.
[0043]
　Further, the present invention is not limited to this, and as in the stator 20C according to the modified example shown in FIG. 10, a plurality of electromagnetic steel sheets 40 may have a mixture of portions bonded to each other in different number of sets in the stacking direction. .. In other words, in the plurality of electrical steel sheets 40, even if a portion bonded every first number of sets in the stacking direction and a portion bonded every second number of sets in the stacking direction are mixed. good. In the modified example shown in FIG. 10, in the plurality of electrical steel sheets 40, the portions bonded in every other set (every two sheets) in the stacking direction and the portions bonded in every two sets (every three sheets) in the stacking direction are bonded. The part and is mixed. That is, a plurality of electrical steel sheets 40 are bonded to each other in different prime numbers in the stacking direction. The unbonded pairs are joined by caulking. Here, in this modification, every other set is bonded in the stacking direction, then every two sets are bonded, and every other set is bonded, and then every two sets are bonded. In other words, the plurality of electrical steel sheets 40 are alternately bonded to every other set (every other set number of the first set) and every other set (every other set number of the second set) in the stacking direction.
　In this modification, instead of every other set and every two sets, bonding may be performed every three or more sets.
　Further, the plurality of electromagnetic steel sheets 40 may not be alternately bonded to each other in the first number of sets and every second set in the stacking direction. For example, the first set number of bonds and the second set number of bonds may be arranged irregularly.
　Further, the plurality of electrical steel sheets 40 may not be alternately bonded to each other of two types, that is, every other number of sets, that is, every other number of sets, and every other number of sets, in the stacking direction. That is, they may be alternately bonded to each other of three or more types.
[0044]
　As shown in FIG. 4, the electromagnetic steel sheets 40 adjacent to each other in the stacking direction bonded by the bonding portion 41 are not completely bonded to each other. These electromagnetic steel sheets 40 are locally bonded to each other.
[0045]
　In the present embodiment, the electromagnetic steel sheets 40 adjacent to each other in the stacking direction are adhered to each other by an adhesive portion 41 provided along the peripheral edge of the electromagnetic steel sheets 40. Specifically, the electromagnetic steel sheets 40 adjacent to each other in the stacking direction are adhered to each other by a first adhesive portion 41a and a second adhesive portion 41b. The first adhesive portion 41a is provided along the outer peripheral edge of the electromagnetic steel sheet 40 in a plan view of the electromagnetic steel sheet 40 when viewed from the stacking direction. The second adhesive portion 41b is provided along the inner peripheral edge of the electromagnetic steel sheet 40 in a plan view of the electromagnetic steel sheet 40 when viewed from the stacking direction. The first and second adhesive portions 41a and 41b are formed in a strip shape in a plan view, respectively.
[0046]
　Here, the band shape also includes a shape in which the width of the band changes in the middle. For example, a shape in which round points are continuous in one direction without being divided is also included in a band shape extending in one direction. Further, along the peripheral edge includes not only the case where it is completely parallel to the peripheral edge but also the case where it has an inclination of, for example, 5 degrees or less with respect to the peripheral edge.
[0047]
　The first adhesive portion 41a is arranged along the outer peripheral edge of the electromagnetic steel sheet 40. The first adhesive portion 41a extends continuously over the entire circumference in the circumferential direction. The first adhesive portion 41a is formed in an annular shape in a plan view of the first adhesive portion 41a when viewed from the stacking direction.
　The second adhesive portion 41b is arranged along the inner peripheral edge of the electromagnetic steel sheet 40. The second adhesive portion 41b extends continuously over the entire circumference in the circumferential direction.
[0048]
　The second adhesive portion 41b includes a plurality of tooth portions 44 and a plurality of core back portions 45. The plurality of tooth portions 44 are provided at intervals in the circumferential direction, and are arranged in each tooth portion 23. The plurality of core back portions 45 are arranged in the core back portion 22, and connect the tooth portions 44 adjacent to each other in the circumferential direction.
　The tooth portion 44 includes a pair of a first portion 44a and a second portion 44b. The first portion 44a is arranged at intervals in the circumferential direction. The first portion 44a extends along the radial direction. The first portion 44a extends in a radial direction in a strip shape. The second portion 44b connects a pair of first portions 44a to each other in the circumferential direction. The second portion 44b extends in a band shape in the circumferential direction.
[0049]
　In the present embodiment, the plan-view shapes of all the adhesive portions 41 provided between the electromagnetic steel sheets 40 are the same. The plan view shape of the adhesive portion 41 means the overall shape of the adhesive portion 41 in a plan view of the electromagnetic steel sheet 40 provided with the adhesive portion 41 when viewed from the stacking direction. The fact that all the adhesive portions 41 provided between the electromagnetic steel sheets 40 have the same plan view shape means that the plan view shapes of all the adhesive portions 41 provided between the electromagnetic steel sheets 40 are completely the same. It does not include only certain cases, but includes substantially the same cases. In the case of substantially the same, it is a case where all the adhesive portions 41 provided between the electromagnetic steel sheets 40 have a common plan view shape of 95% or more.
[0050]
　In the present embodiment, the adhesive area ratio of the electromagnetic steel sheet 40 by the adhesive portion 41 is 1% or more and 40% or less. In the illustrated example, the adhesive area ratio is 1% or more, 20% or less, and specifically 20%. The adhesive area ratio of the electromagnetic steel sheet 40 by the adhesive portion 41 is the adhesive portion 41 of the first surface of the electromagnetic steel plate 40 with respect to the area of ​​the surface facing the stacking direction (hereinafter referred to as the first surface of the electromagnetic steel sheet 40). Is the ratio of the area of ​​the region (adhesive region 42) provided with. The region provided with the adhesive portion 41 is a region (adhesive region 42) of the first surface of the electrical steel sheet 40 in which the adhesive cured without being divided is provided. The area of ​​the region where the adhesive portion 41 is provided can be obtained, for example, by photographing the first surface of the magnetic steel sheet 40 after peeling and analyzing the imaged result.
[0051]
　In the present embodiment, the bonding area ratio of the electromagnetic steel sheets 40 by the bonding portion 41 between the electromagnetic steel sheets 40 is 1% or more and 20% or less. In both electrical steel sheets 40 adjacent to each other in the stacking direction, the adhesive area ratio of the electrical steel sheets 40 by the adhesive portion 41 is 1% or more and 20% or less. When the adhesive portions 41 are provided on both sides in the stacking direction with respect to one electrical steel sheet 40, the adhesive area ratios on both sides of the electrical steel sheet 40 are 1% or more and 20% or less.
　By adhering the electromagnetic steel sheet 40 with the adhesive portion 41, it is possible to easily secure the adhesive area (bonding area) as compared with the case where the electromagnetic steel sheet 40 is crimped.
[0052]
　As shown in FIG. 5, crimps C1 and C2 are formed on the electromagnetic steel sheets 40 that are crimped to each other. The caulking C1 and C2 include a first caulking C1 provided on the core back portion 22 and a second caulking C2 provided on the teeth portion 23.
[0053]
　A plurality of first caulking C1s are arranged at equal intervals along the circumferential direction. In the illustrated example, the first caulking C1 is arranged so as to be offset from the teeth portion 23 along the circumferential direction. The first caulking C1 is arranged in the middle of the adjacent teeth portions 23 along the circumferential direction. The first caulking C1 is arranged at the center of the core back portion 22 along the radial direction.
　The second caulking C2 is provided in all the teeth portions 23. The second caulking C2 is arranged at the center of each tooth portion 23 in the circumferential direction. Two second caulking C2s are arranged side by side in the radial direction on each tooth portion 23.
[0054]
　As shown in FIG. 6, the first caulking C1 includes a convex portion C11 and a concave portion C12 provided on each electrical steel sheet 40. The convex portion C11 protrudes from the electromagnetic steel sheet 40 in the stacking direction. The concave portion C12 is arranged in a portion of each electrical steel sheet 40 located on the back side of the convex portion C11. The recess C12 is recessed in the stacking direction with respect to the surface (first surface) of the electromagnetic steel sheet 40. The convex portion C11 and the concave portion C12 are formed by, for example, pressing each of the electromagnetic steel sheets 40.
　Here, of the two electrical steel sheets 40 crimped to each other, one is referred to as the first electrical steel sheet 40 and the other is referred to as the second electrical steel sheet 40. The first caulking C1 is formed by fitting the convex portion C11 of the first electromagnetic steel sheet 40 into the concave portion C12 of the second electrical steel sheet 40. By fitting the convex portion C11 into the concave portion C12 and forming the first caulking C1, the relative displacement between the two electromagnetic steel sheets 40 adjacent to each other in the stacking direction is regulated.
[0055]
　The second caulking C2 has the same configuration as the first caulking C1. The second caulking C2 includes the convex portion C11 and the concave portion C12 provided on each of the electromagnetic steel sheets 40. The second caulking C2 is formed by fitting the convex portion C11 of the first electromagnetic steel sheet 40 into the concave portion C12 of the second electrical steel sheet 40. By fitting the convex portion C11 into the concave portion C12 and forming the second caulking C2, the relative displacement between the two electromagnetic steel sheets 40 adjacent to each other in the stacking direction is regulated.
[0056]
　The shapes of the convex portion C11 and the concave portion C12 are not particularly limited. For example, the electromagnetic steel sheet 40 may be provided with a through hole as the recess C12.
　Further, the direction in which the convex portion C11 protrudes and the direction in which the concave portion C12 is recessed may be either the first side D1 or the second side D2 in the stacking direction.
[0057]
　In the present embodiment, the caulking C1 and C2 and the adhesive portion 41 are arranged at positions where they do not overlap in a plan view and avoid each other. The caulking C1 and C2 and the adhesive portion 41 are arranged so as to be offset in a plan view. The total area of ​​the caulking C1 and C2 in the plan view is smaller than the total area of ​​the bonded portion 41.
[0058]
　Further, in the present embodiment, the electromagnetic steel sheets 40 that are crimped to each other are not bonded to each other. In other words, the adhesive portion 41 is not provided between the electromagnetic steel sheets 40 that are crimped to each other.
　Further, in the present embodiment, the electromagnetic steel sheets 40 bonded to each other are not crimped. In other words, in the electromagnetic steel sheets 40 that are bonded to each other, the convex portion C11 and the concave portion C12 are not fitted together. That is, the regulation of the relative displacement of the electromagnetic steel sheets 40 bonded to each other is not realized by at least the fitting of the convex portion C11 and the concave portion C12.
[0059]
　Joining by caulking can improve dimensional accuracy as compared with joining by bonding. Here, out of all the sets of the electromagnetic steel sheets 40 adjacent to each other in the stacking direction, some sets of the electromagnetic steel sheets 40 are crimped to each other. Therefore, the accuracy of the shape of the portion of the stator core 21 formed by some of these sets can be improved. As a result, the accuracy of the outer shape of the stator core 21 can be improved. Therefore, the handleability of the stator core 21 can be ensured. For example, even when winding the winding around the stator core 21, it can be wound with high accuracy.
　In the present embodiment, when the winding is passed through the slots between the teeth portions 23 adjacent to each other in the circumferential direction, the above-mentioned action and effect of ensuring the handleability is remarkably achieved. That is, if the dimensional accuracy of the slot is improved, the winding can be easily wound around the teeth portion 23 as designed. As a result, the winding space factor in the slot can be increased. As a result, the electrical load in the slot can be increased.
[0060]
　However, joining by caulking may generate a short-circuit current (stray current) between the electromagnetic steel sheets 40 adjacent to each other in the stacking direction. Here, of all the sets of the electromagnetic steel sheets 40 adjacent to each other in the stacking direction, the remaining sets of the electromagnetic steel sheets 40 except for the part of the sets are bonded to each other. Therefore, it is possible to suppress the generation of stray current between the remaining sets of electromagnetic steel sheets 40. As a result, the magnetic characteristics of the stator core 21 can be improved.
[0061]
　A plurality of electrical steel sheets 40 are bonded to each other in one or more sets (every other set in the present embodiment) in the stacking direction. Therefore, it is possible to prevent the electromagnetic steel sheet 40 joined by adhesion from being locally concentrated on a part of the stator core 21 in the stacking direction. In other words, the electromagnetic steel sheets 40 joined by adhesion can be dispersed in the stacking direction. As a result, the accuracy of the outer shape of the stator core 21 can be further improved.
[0062]
　By the way, the stator core 21 also has a unique resonance frequency like a general article. If the resonance frequency of the stator core 21 is low, resonance is likely to occur when general vibration is input. Therefore, it is preferable that the resonance frequency of the stator core 21 is high.
　Here, when a plurality of electrical steel sheets 40 are bonded to each other in N layers in the stacking direction, the resonance frequency of the stator core 21 tends to depend on N.
　That is, in the case of bonding every N sets, (N + 1) sheets of electrical steel sheets 40 are arranged between the bonding portions 41 adjacent to each other in the stacking direction, and these electrical steel sheets 40 are crimped to each other. When the bonding strength by the bonding portion 41 is lower than the bonding strength by caulking, the (N + 1) sheets of electromagnetic steel sheets 40 are likely to behave integrally with the bonding portion 41 as a starting point. In other words, the (N + 1) sheets of electrical steel sheets 40 behave as if they were one block. In such a stator core 21, when a plurality of electromagnetic steel sheets 40 are bonded at equal intervals in the stacking direction at intervals of N, the resonance frequency of the stator core 21 is affected by a divisor of N. Further, when a plurality of electromagnetic steel sheets 40 are adhered to N1 sets, N2 sets, ... The larger the divisor or the least common multiple, the higher the resonance frequency of the stator core 21.
[0063]
　A plurality of electrical steel sheets 40 are adhered to every other prime number set (every other set in the present embodiment) in the stacking direction. Therefore, even when a plurality of electrical steel sheets 40 are bonded to every N pairs (however, N is a prime number) at equal intervals in the stacking direction, N is a prime number and the above divisor is increased. can do. Further, even when a plurality of electrical steel sheets 40 are bonded to N1 sets, N2 sets, ..., Which are different from each other in the stacking direction, the least common multiple for N1, N2 ... Can be increased. Therefore, the resonance frequency of the stator core 21 can be increased. As a result, for example, the resonance frequency can be set to a frequency higher than the audible range. Thereby, for example, even when the stator core 21 is applied to an electric motor as in the present embodiment, it is possible to suppress the generation of noise due to resonance.
[0064]
　In the modified example as shown in FIG. 10, a plurality of electromagnetic steel sheets 40 have a mixture of portions bonded to each other in different number of sets in the stacking direction. Therefore, when it is assumed that the plurality of electromagnetic steel sheets 40 are adhered to N1 sets, N2 sets, ... Therefore, the resonance frequency of the stator core 21 can be increased according to the least common multiple of the number of pairs thereof. As a result, the generation of noise due to resonance can be further suppressed.
　It should be noted that such an action effect is remarkably effective when the prime numbers are bonded to each other in different prime numbers in the stacking direction as in the above embodiment. That is, in this case, the least common multiple can be increased.
[0065]
　The technical scope of the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.
[0066]
　The shape of the stator core is not limited to the form shown in the above embodiment. Specifically, the dimensions of the outer diameter and inner diameter of the stator core, the product thickness, the number of slots, the dimensional ratio between the circumferential direction and the radial direction of the teeth portion 23, the dimensional ratio in the radial direction between the teeth portion 23 and the core back portion 22, etc. Can be arbitrarily designed according to the desired characteristics of the rotating electric machine.
[0067]
　In the rotor of the above embodiment, a set of two permanent magnets 32 form one magnetic pole, but the present invention is not limited to this. For example, one permanent magnet 32 ​​may form one magnetic pole, or three or more permanent magnets 32 may form one magnetic pole.
[0068]
　In the above-described embodiment, the permanent magnet field type motor has been described as an example of the rotary electric machine, but the structure of the rotary electric machine is not limited to this as illustrated below, and various publicly known not to be exemplified below. Structure can also be adopted.
　In the above-described embodiment, the permanent magnet field type motor has been described as an example as the synchronous motor, but the present invention is not limited to this. For example, the rotary electric machine may be a reluctance type electric machine or an electromagnet field type electric machine (winding field type electric machine).
　In the above-described embodiment, the synchronous motor has been described as an example of the AC motor, but the present invention is not limited to this. For example, the rotary electric machine may be an induction motor.
　In the above-described embodiment, the AC motor has been described as an example of the motor, but the present invention is not limited to this. For example, the rotary electric machine may be a DC motor.
　In the above-described embodiment, the electric machine has been described as an example of the rotary electric machine, but the present invention is not limited to this. For example, the rotary electric machine may be a generator.
[0069]
　In the above embodiment, the case where the laminated core according to the present invention is applied to the stator core is illustrated, but it can also be applied to the rotor core.
[0070]
　In addition, it is possible to replace the components in the embodiment with well-known components as appropriate without departing from the spirit of the present invention, and the above-mentioned modifications may be appropriately combined.
[0071]
　Next, a verification test was conducted to verify the above-mentioned effects. This verification test was carried out by simulation using software. As the software, JMAG, a finite element method electromagnetic field analysis software manufactured by JSOL Corporation, was used.
　As the verification test, a first verification test and a second verification test were carried out.
[0072]
(First verification test) In
　the first verification test, the action and effect based on the mixture of caulking and adhesion were verified.
　In this verification test, simulations were carried out for the stators of Comparative Examples 1 and 2 and the stators of Examples 1 to 3.
[0073]
　Common to both the stators of Comparative Examples 1 and 2 and the stators of Examples 1 to 3, the stator 20 according to the embodiment shown in FIGS. 1 to 6 is used as a basic structure, and the stator 20 is described below. I changed the point. That is, the thickness of the electrical steel sheet was 0.20 mm, the stacking thickness of the laminated core was 50 mm, and the number of electrical steel sheets was 250.
[0074]
　Then, in the stator of Comparative Example 1, 250 electromagnetic steel sheets were joined by caulking in all layers. In the stator of Comparative Example 2, 250 electromagnetic steel sheets were joined by adhesion in all layers. In the stator of Example 1, 250 electromagnetic steel sheets were bonded by bonding every other set in the stacking direction, and the rest were bonded by caulking (alternately bonded by bonding and caulking). In the stator of Example 2, 250 electromagnetic steel sheets were bonded by bonding every two sets in the stacking direction, and the rest were bonded by caulking. In the stator of Example 3, 125 of the 250 electromagnetic steel sheets on one side in the stacking direction were bonded by adhesion, and the remaining 125 sheets were bonded by caulking.
[0075]
　For each of the stators of Comparative Examples 1 and 2 and Examples 1 to 3, the iron loss per magnetic steel sheet and the dimensional accuracy as the stator core were confirmed. The iron loss was calculated by a simulation using the above software. The dimensional accuracy was evaluated by the amount of deviation from the target dimensions when five stator cores were manufactured in each example.
[0076]
　The results are shown in Table 1 below.
[0077]
[table 1]

[0078]
　From the above, for example, in Example 1, an improvement in iron loss of 8.8% (= (25.2-23.4) / 25.2) was observed as compared with Comparative Example 1, and the like. In all of 3 and 3, it was confirmed that the iron loss was improved and the generation of stray current was slight as compared with Comparative Example 1. Moreover, in Examples 1 to 3, it was obtained that the dimensional accuracy was superior to that in Comparative Example 2.
[0079]
(Second verification test) In
　the second verification test, the relationship between the adhesion interval and resonance was verified.
　In this verification test, simulations were carried out for the stators of Examples 11 to 21.
[0080]
　Common to all of the stators of Examples 11 to 21, the stator 20 according to the embodiment shown in FIGS. 1 to 6 is used as the basic structure, and the following points are changed with respect to the stator 20. That is, the thickness of the electrical steel sheet was 0.20 mm, the stacking thickness of the laminated core was 50 mm, and the number of electrical steel sheets was 250.
[0081]
　Then, the stators of Examples 11 to 19 were set as follows.
　In the stator of Example 11, 250 electromagnetic steel sheets were bonded by bonding every other set in the stacking direction, and the rest were bonded by caulking (alternately bonded by bonding and caulking).
　In the stator of Example 12, 250 electromagnetic steel sheets were bonded by bonding every two sets in the stacking direction, and the rest were bonded by caulking.
　Similarly, for the stators of Examples 13 to 19, 250 electromagnetic steel sheets are arranged in 3 sets, 4 sets, ... As the number increased, the number was increased one by one.
[0082]
　Further, the stators of Examples 20 and 21 were set as follows.
　In the stator of Example 20, in 250 magnetic steel sheets, a portion bonded every three sets in the stacking direction and a portion bonded every five sets in the stacking direction are mixed and not bonded. Was joined by caulking.
　In the stator of Example 21, 250 pieces of electrical steel sheets were bonded to every three sets in the stacking direction, every five sets in the stacking direction, and every seven sets in the stacking direction. After mixing, the unbonded sets were joined by caulking.
[0083]
　Regarding the stators of Examples 11 to 19, it was confirmed whether or not vibration in the audible range was generated at the time of resonance.
[0084]
　The results are shown in Table 2 below.
[0085]
[Table 2]

[0086]
　From the above, it was confirmed that the vibration in the audible range was weak in the stators of Examples 11, 12, 13, 15, and 17 (stators in which a plurality of electromagnetic steel sheets were bonded to each other in the stacking direction in every prime number set).
　Further, it was confirmed that the vibration in the audible range was extremely weak in the stators of Examples 20 and 21 (in a plurality of electromagnetic steel sheets, the portions bonded to each other in different prime numbers in the stacking direction are mixed). rice field.
Industrial applicability
[0087]
　According to the present invention, it is possible to improve the magnetic characteristics while ensuring the dimensional accuracy of the outer shape. Therefore, the industrial applicability is great.
Code description
[0088]
10 Rotating machine
21 Stator core (laminated core)
22 Core back part
23 Teeth part
40 Electromagnetic steel plate
The scope of the claims
[Claim 1]

　It is a laminated core 　in which a plurality of electrical steel sheets laminated to each other are provided and all sets of electromagnetic steel sheets adjacent to each other in the stacking direction are fixed to
　each other. A laminated core in which the steel sheets are crimped and not bonded, and the remaining set of electromagnetic steel sheets are not bonded and crimped.
[Claim 2]
　The laminated core according to claim 1, wherein the plurality of electromagnetic steel sheets are bonded to each other in one or more sets in the laminated direction.
[Claim 3]
　The laminated core according to claim 2, wherein the plurality of electromagnetic steel sheets are bonded to each other in prime numbers in the laminated direction.
[Claim 4]
　The laminated core according to claim 2 or 3, wherein in the plurality of electromagnetic steel sheets, portions that are bonded to each other in different number of sets are mixed in the laminated direction.
[Claim 5]
　The electrical steel sheet has an annular core back portion and a plurality of teeth portions that protrude from the core back portion in the radial direction of the core back portion and are arranged at intervals in the circumferential direction of the core back portion. The laminated core according to any one of claims 1 to 4.
[Claim 6]
　The laminated core according to any one of claims 1 to 5, wherein the average thickness of the bonded portion is 1.0 μm to 3.0 μm.
[Claim 7]
　The laminated core according to any one of claims 1 to 6, wherein the average tensile elastic modulus E of the bonded portion is 1500 MPa to 4500 MPa.
[Claim 8]
　The laminated core according to any one of claims 1 to 7, wherein the adhesive portion is a room temperature adhesive type acrylic adhesive containing SGA made of an elastomer-containing acrylic adhesive.
[Claim 9]
　A rotary electric machine comprising the laminated core according to any one of claims 1 to 8.