JP2002272025A - Stacked cores for rotating machine and manufacturing method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a stacked cores for a rotating machine which can reduce the eddy current loss. SOLUTION: On a sheet core 2, recessed parts 4a formed on the surface of a magnet pole part and protruding parts 4b that project on its back surface are provided. The recessed parts 4a and the protruding parts 4b of the sheet cores 2, which are stacked, are press-connected to each other. But press- connectable positions and non press-connectable ones of the recessed parts 4a to the protruding parts 4b are provided alternately in the circumferential direction. In the stacked cores made by stacking these sheet cores 2, the press- connecting parts 'A' are dislocated in the circumferential direction for each group of a given number of pieces of the sheet cores 2. This structure prevents the press-connecting parts A from continuing in the stacking direction, so that the eddy current loss can be reduced sharply. Also, by rotating and stacking a given number of pieces of the sheet cores 2 in the circumferential direction, the total length of the stacking direction can be made equal over the entire circumference. In this way, good balance is made, when it is rotated, with the effect of lessening the vibrations and abnormal noises.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laminated core for a rotating machine constituted by laminating a plurality of sheet cores.

[0002]

2. Description of the Related Art In general, an armature core used in a rotating machine is formed by laminating a plurality of thin iron plates (referred to as sheet cores) having an insulating coating on a surface thereof in order to make eddy current hard to flow. It is configured. As shown in FIG. 5, for example, the stacked sheet cores before and after the stacking are connected by press-fitting a connecting portion (a convex portion 110 and a concave portion 120) provided on the sheet core 100. Alternatively, there is a method in which the sheet cores are joined by welding and connected.

[0003]

However, in the above method, the connecting portions (the convex portions 110 and the concave portions 120) are connected to the sheet core 100.
When forming the, because the insulating coating of the connection part is destroyed,
At the connection portion, the sheet cores 100 are connected as an electric circuit. Further, even in the case of joining by welding, the sheet cores 100 are connected as an electric circuit through the joint. For this reason, an eddy current is generated in the armature core, and there is a problem that performance is reduced due to eddy current loss. The present invention has been made based on the above circumstances, and its purpose is to
An object of the present invention is to provide a laminated core of a rotating machine capable of reducing eddy current loss.

[0004]

(Means for Solving the Problems) In the laminated core of the present invention, the number of magnetic poles is set to be smaller than the number of magnetic poles m at which adjacent sheet cores are fastened. Also,
The mechanical angle between magnetic poles adjacent in the circumferential direction of the sheet core is θ (ra
In the case of d), the fastening point where the nth sheet core and the preceding sheet core are fastened in the stacking direction and the fastening point where the nth sheet and the subsequent sheet cores are fastened are integers a × θ ( ra
It is shifted entirely in the circumferential direction by d).

According to this configuration, of the m magnetic pole portions,
There is a magnetic pole part having no fastening part. Therefore, when the fastening portions are entirely shifted in the circumferential direction between the n-th sheet core and the sheet cores before and after the n-th sheet core, the position of the magnetic pole portion having no fastening portion is naturally shifted in the circumferential direction. As a result, the magnetic pole portion having no fastening portion and the magnetic pole portion having the fastening portion are mixed in the stacking direction, so that eddy current does not flow in the entire stacking direction, and eddy current loss can be reduced.

[0006] (Means of Claim 2) In the laminated core of the rotating machine according to Claim 1, the fastening points where adjacent sheet cores are fastened are uniformly distributed over the entire circumference in the entire laminating direction. In this case, even if the fastening points where the adjacent sheet cores are fastened to each other are set to be smaller than the number m of magnetic poles, the fastening locations are uniformly distributed over the entire circumference in the stacking direction, so that the rotational balance of the laminated core is improved. Can be kept.

According to a third aspect of the present invention, in the laminated core of the rotating machine according to the second aspect, when the total number of sheet cores to be laminated is N, the following relationship holds: N = integer a × number of magnetic poles m It is characterized by doing. According to this configuration, it is possible to arrange the fastening portions of the adjacent sheet cores evenly distributed over the entire circumference in the entire laminating direction.

(Means of Claim 4) In the laminated core of any one of the rotating machines according to any one of claims 1 to 3, the fastening points are entirely integers a × θ (rad) in the circumferential direction for each sheet core. It is provided shifted. In this case, the eddy current is applied to the sheet core 1
Since the cutting can be performed for each sheet, the effect of reducing the eddy current loss is great.

According to a fifth aspect of the present invention, in the laminated core of any one of the rotating machines according to any one of the first to third aspects, the fastening point is an integer a × θ for each of a predetermined number of sheet core groups that are continuously laminated.
(rad) so as to be entirely shifted in the circumferential direction. In this case, the cycle time can be reduced as compared with the case where the fastening portion is shifted in the circumferential direction for each sheet core, so that productivity can be improved.

According to a sixth aspect of the present invention, there is provided a method of manufacturing a laminated core for a rotating machine according to any one of the first to fifth aspects, wherein the sheet cores are stacked one by one or a plurality of times. Each time or periodically, relative to the previously fastened sheet core, the two are rotated relative to each other so that the fastening point of the next laminated sheet core is shifted by an integer a × θ (rad) in the circumferential direction. Let it be laminated.

As a result, the magnetic pole portions having no fastening portions are not continuous in the laminating direction but are dispersed in the circumferential direction, so that the eddy current can be cut off effectively. In addition, the sheet core that has been fastened up to that time and the sheet core to be stacked next are relatively rotated and stacked to reduce unevenness in the thickness of the sheet core. As a result, the thickness in the entire laminating direction can be provided uniformly over the entire circumference, so that the balance at the time of rotation is improved and the occurrence of vibration and abnormal noise can be reduced.

[0012]

Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic diagram showing a method of fastening the laminated core 1. The laminated core 1 of this embodiment is used for an armature (rotor) of a DC motor, and is configured by laminating a plurality of (for example, 48) thin sheet cores 2 as shown in FIG. You. FIG. 2 shows a front shape (a) and a side shape (b) of the laminated core 1.

The sheet core 2 is press-formed from a strip-shaped material 3 (see FIG. 1) having an insulating coating applied to its surface in advance.
As shown in FIG. 3, a round hole 2a for inserting a rotation shaft (not shown) is formed in the center, and a plurality of slots 2b are punched around the hole 2a. )
Are formed radially. Further, in a step before or after the press working, a connecting portion 4 is provided at a portion where each magnetic pole portion 2c is formed.

As shown in FIG. 4, the connecting portion 4 comprises a concave portion 4a formed on the front surface by a punch or the like and a convex portion 4b projecting from the back surface thereof. The concave portion 4a and the convex portion 4b are press-fitted (press-fit). However, between the other sheet cores 2 to be superimposed, portions where the press-fitting and fastening of the concave portions 4a and the protruding portions 4b of each other are possible and portions where the press-fitting and fastening are impossible are alternately provided in the circumferential direction. . Specifically, the outer diameter of the projections 4b provided at eight locations in the circumferential direction is formed slightly smaller every other location, and the projections 4b are provided so as not to be pressed into the recesses 4a of the other sheet core 2 (there is a gap). .

Next, a method of manufacturing the laminated core 1 will be described with reference to FIG. a) The sheet cores 2 punched by a press from the band-shaped material 3 are sequentially housed in a cylinder formed in the lower die 5,
When a predetermined number of sheets (for example, three sheets) have been stored, the upper mold 6 is pushed in and press-fitted. b) Subsequently, when the next predetermined number of sheet cores 2 are housed in the cylinder of the lower die 5, the part that can be press-fit and fastened to the already fastened sheet core 2 group is displaced in the circumferential direction. Is rotated by a predetermined angle (45 degrees in this embodiment).

C) Thereafter, the upper die 6 is pushed in, and the newly laminated 3
The two sheet cores are press-fitted and fastened. d) Subsequently, the next predetermined number of sheet cores 2 are sequentially housed in the cylinder of the lower mold 5 without rotating in the circumferential direction,
The upper die 6 is pushed in and press-fitted. e) Thereafter, the above procedures b) to d) are repeated, and all the sheet cores 2 are laminated and press-fitted. As a result, the press-fit fastening portion A in which the concave portions 4a and the convex portions 4b of the superposed sheet cores 2 are press-fitted, and the non-fastening portion B in which the convex portion 4b having a small outer diameter fits with the concave portion 4a. They are alternately provided in the circumferential direction (see FIG. 1).

(Effect of this embodiment) The laminated core 1 of this embodiment
The press-fit fastening portions A are laminated with a predetermined number (three) of sheet cores 2 shifted in the circumferential direction. As a result, the press-fit fastening portion A does not continue in the laminating direction in all the eight magnetic pole portions 2c in the circumferential direction, so that the eddy current loss can be significantly reduced. Further, by stacking the sheet cores 2 by rotating in the circumferential direction for each predetermined number of sheets, it is possible to prevent the thickness deviation occurring in each sheet core 2 from being accumulated, and to reduce the thickness in the entire stacking direction. (The core length in the axial direction) can be provided uniformly over the entire circumference. As a result, the balance at the time of rotation is improved, and there is an effect that generation of vibration and abnormal noise can be reduced.

In this embodiment, since the portions that can be press-fitted and the portions that cannot be press-fitted are alternately provided in the eight magnetic pole portions 2c in the circumferential direction, a predetermined number of sheet cores 2c are provided. 2 is rotated in the circumferential direction every other time for press-fitting, but it is not always necessary to follow the procedure of the above-described embodiment. That is, the magnetic pole portions 2c adjacent in the circumferential direction of the sheet core 2
When the mechanical angle between them is θ (rad) (see FIG. 3), the press-fit fastening portion A where the n-th sheet core and the preceding sheet core 2 are fastened in the stacking direction, and the n-th sheet core and the subsequent sheet core It suffices that the press-fit fastening portion A where the two are fastened is entirely shifted in the circumferential direction by an integer a × θ (rad).

However, in order for the press-fit fastening portions A to be evenly arranged on the entire circumference in the entire laminating direction, the following relationship must be satisfied. When the total number of the sheet cores 2 to be stacked is N, N = integer a × number of magnetic poles m If this relationship is established, the sheet core 2 is converted to an integer a × θ (ra
When the press-fit fastening portion A is shifted by rotating in the circumferential direction only by d), the press-fit fastening portion A is always arranged uniformly over the entire circumference.

Further, it is not necessary to alternately provide a portion in which press-fitting can be performed and a portion in which press-fitting cannot be performed in the circumferential direction. For example, in the sheet core 2 shown in FIG. 3, only two radially opposed portions that cannot be press-fitted may be provided, and the remaining six portions may be provided as press-fittable portions,
Alternatively, only one place where press-fitting is impossible is provided,
The remaining seven locations may be provided as press-fittable locations. Even in these cases, if the above relationship is established, the parts that cannot be press-fitted are laminated while being shifted in the circumferential direction by an integer a × θ (rad), and finally the press-fitted joint A is circumferentially formed in the entire laminating direction. It can be arranged evenly in the direction.

In the above embodiment, the adjacent sheet cores 2 are fastened to each other by the connecting portions 4 (the concave portions 4a and the convex portions 4b) provided on the sheet core 2. Can be applied. Further, in the above embodiment, the configuration of the present invention is applied to the armature core (rotor), but can be applied to the stator core.

[Brief description of the drawings]

FIG. 1 is a schematic view showing a method of fastening a laminated core.

FIG. 2 is an axial front view (a) and a side view (b) of a laminated core.
It is.

FIG. 3 is a front view (a) and a side view (b) of a sheet core.

FIG. 4 is an enlarged sectional view showing a connecting portion (a concave portion and a convex portion) of the sheet core.

FIG. 5 is a schematic view showing a method of fastening a laminated core (prior art).

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Laminated core 2 Sheet core 2c Magnetic pole part A Press-fit fastening part (fastening point) θ Mechanical angle between magnetic pole parts

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Kiyonori Moroto 1-1-1 Showa-cho, Kariya-shi, Aichi F-term in Denso Co., Ltd. 5H002 AA03 AA04 AB01 AC02 AC08

Claims (6)

[Claims] 1. A laminated core of a rotating machine comprising a plurality of sheet cores each having m magnetic pole portions, wherein the adjacent sheet cores are fastened to each other at their magnetic pole portions. The number of the fastening points at which the sheet cores are fastened to each other is set to be smaller than the number m of magnetic poles, and when the mechanical angle between the magnetic pole portions adjacent in the circumferential direction of the sheet core is θ (rad), n sheets are stacked in the laminating direction. The fastening point at which the eye and the preceding sheet core are fastened to each other and the fastening point at which the n-th sheet core and the subsequent sheet core are fastened to each other in the circumferential direction by an integer a × θ (rad). A laminated core of a rotating machine. 2. The laminated core of a rotating machine according to claim 1, wherein the fastening positions at which the adjacent sheet cores are fastened to each other are:
A laminated core for a rotating machine, wherein the laminated cores are evenly distributed over the entire circumference in the laminating direction. 3. The laminated core of a rotating machine according to claim 2, wherein, when the total number of the sheet cores to be laminated is N, the following relationship is established: N = integer a × magnetic pole number m. The laminated core of the rotating machine. 4. The laminated core for a rotating machine according to claim 1, wherein the fastening portion is an integer a × θ (ra) for each sheet core.
d) The laminated core of the rotating machine, which is provided so as to be entirely shifted only in the circumferential direction. 5. The laminated core for a rotary machine according to claim 1, wherein the fastening portion is rotated by an integer a × θ (rad) for each of a predetermined number of sheet core groups that are continuously laminated. A laminated core for a rotating machine, which is provided so as to be entirely displaced in a direction. 6. The method for manufacturing a laminated core for a rotary machine according to claim 1, wherein the sheet cores are stacked one by one or a plurality of times at every time or periodically. Specifically, with respect to the sheet cores that have been fastened so far, the fastening points of the next stacked sheet cores are shifted in the circumferential direction by an integer a × θ (rad),
A laminated core for a rotating machine, characterized in that both are relatively rotated and laminated.