JPS6016183B2 - Manufacturing method of stator core for rotating electrical machines - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the shape of a stator core of a rotating electrical machine such as an induction motor, and more particularly to a method of manufacturing a stator core that can save core material.

The overall shape of the stator core of a small rotating electric machine is formed by punching a steel plate, and the material is generally a strip steel plate, which is then continuously punched to form the core. .

A stator is then formed by stacking and integrating a predetermined number of punched iron cores.・Figure 1 is a diagram showing the shape of this type of conventional iron 0 and its punched state,
This conventional iron core 1 has an outer periphery that includes first straight sections 2a, 2a that are parallel to each other, second straight sections 2b, 2b that are perpendicular to these and parallel to each other, and a first straight section. 2
It is formed by an arcuate part 3 formed between the end part of a and the second straight part 2b, and a slot 5 for accommodating the stator windings is formed in the inner fold part 4.

These iron cores I are sequentially punched out from one strip-shaped steel plate 6 while feeding the steel plate as shown in the figure. In this conventional type, the straight portions 2a and 2b are formed on the outer periphery in order to save the steel plate 6 as a material.

That is, the first straight portion 2a is formed during punching of the adjacent core, and the second straight portion 2b is aligned with the side of the steel plate 6 to form the disc-shaped core of the outer flea D. Compared to the case, it becomes possible to use a steel plate having a dimension W smaller than this dimension D, and the number of cores that can be punched from one steel plate increases, and the area of the unnecessary part 7 shown by diagonal lines becomes narrower. This makes it possible to save the steel plate 6. (Note that the inside of the inner folding portion 4 is used for the rotor core.) However, when punching the core in one row from one strip-shaped material in this way, the bottom of the slot 5 and the outer periphery are Because the magnetic properties required of the core make it impossible to make the difference in each slot in the middle too large, there is a limit to how much material can be saved.

The present invention aims to overcome the ridges in the prior art and provide a method for manufacturing a stator core that can further save core material.

The present invention is characterized in that a stator core is punched out in a shape that allows cores to be punched in two or more rows from a single strip-shaped material. That is, the iron core according to the present invention has an outer circumference formed by two first straight parts parallel to each other, and two second straight parts that are perpendicular to the first straight parts, parallel to each other, and shorter than the first straight parts. and four third straight parts which are formed from both ends of the second straight part and extend between the second straight part and the first straight part, and which are parallel to each other and are opposed to each other with the center of the iron core as the center.
It has a shape with a straight portion, and is characterized by punching out multiple rows of the iron core from a single strip steel plate. Next, an embodiment of the present invention will be explained with reference to FIG.

FIG. 2 shows the shape of the stator core according to the present invention.
The iron core 8 has two first straight portions 9a, 9, whose outer peripheral portions are relatively long and parallel to each other, and two first straight portions 9a, 9, which are parallel to each other and at right angles to the first straight portions. Saddle 2 is the first straight portion 9a. , 9a2, the second straight portion 9 is shorter than the length of 9a2.
b,, 9b2, four third straight parts 9c, - 9c4 formed from both ends of the second straight parts 9b, 9b2 between the second straight parts and the first straight part, and It consists of four arcuate parts 9d and 9d4 formed from both ends of the small straight part 9a2 to the ends of the third straight parts 9c and 9c4. and third straight portion 9c. ~ In 9c4,
Items facing each other across the center ○ of the iron core (9
c, and 9c3, and 9c2 and 9c4) are parallel to each other. The arcuate portion 9d, ~9 is in the shape of an arc with a diameter D centered on point ○, and the width W of the straight portion gb and 9b2 (9 phantom and 9
The same applies to a2) is 4· from the diameter D. By adopting such a shape, as shown in FIG. 3, punching in two rows in a staggered manner can be performed while saving material. As shown in Figure 3, the iron core is 8g, 8h, 8i,...
When punching out the core 8i in a staggered manner, the first straight portion 9a2 is the core 8.
The first straight part ga2 of the iron core 8g coincides with the first straight part 9 of the iron core 8g (that is, the iron core is cut at the 9th peak, 92), and one of the second straight parts 9b, The other second straight portion 9b2 coincides with the side of the strip steel plate 10 and is located between the iron cores 8h and 8i, and the third straight portion 9c2, 9c3
are punched so as to coincide with the third straight portion 9c4 of the iron core 8i and the third straight portion 9c of the iron core 8h, respectively. FIG. 4 shows an example of the order of items by punching in this two-row punching. The arrows in FIG. 4 indicate the feeding direction of the steel plate, and the steel plate 10 is sequentially and intermittently fed in the direction of the arrow, and the punching operation is performed in a stopped state. The shaded areas indicate the parts that are punched out at the same time. That is, the cut portions 14 to 1 are between the iron cores 8h to 8k.
7, and when a finished product is obtained for cores 8h to 8i, at the same time, the rotor core portion 1 of cores 8j and 8k is cut.
3 (details are omitted), iron core 8〆, 8m
stator slots, and other waste portions 12 shown as shaded areas.
is punched out, and in the next punching process, 8 pieces and 8 pieces are each made of 8 pieces.
When the machine reaches position j, 8k, the same punching operation as before is performed. Therefore, it is possible to continuously obtain a core punched in two rows. By punching out the iron 0 in this way, the first
Compared to the case shown in the figure, the width W′ (=2W− It is sufficient to prepare the steel plate w) as the material.

A comparison of the method according to this embodiment and the method shown in FIG. 1 using specific numbers is as shown in the table below. As shown in this table, when the iron core with the structure shown in Fig. 2 is obtained by punching in two rows as shown in Figs. A material saving of 4.3% is possible.

Although FIGS. 3 and 4 show an example in which the iron ○ having the shape shown in FIG. 2 is obtained by punching in two rows, the present invention is not limited to punching in two rows, but may also be performed by punching in three or more rows. It is easy to understand that an iron core having the shape of
Further material savings are possible than in the case of staggered row punching.

As described above, according to the stator core manufacturing method according to the present invention, two or more rows of staggered punching can be performed from a strip-shaped steel plate, which greatly contributes to reducing the price of rotating electric machines by saving materials.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the shape of a conventional stator core and its punched state, FIG. 2 is a diagram showing an example of the shape of the core according to the present invention, and FIG. 3 is a diagram showing the punched state of the core in FIG. 2. 4 are diagrams for explaining the punching order in the punching of FIG. 3. 4. ．．・・・．・Stator core inner diameter, 5...Slot, 8,8g~8m...Iron core, 9a,,9a2...
First straight part, 9b,, 9b2... Second straight part,
9c, ~9c4...Third straight section, 9d, ~9d
4...Arc-shaped part, 12...Discarded part, 1
3... Rotor part, 14-17... Cutting line. Figure 1 Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] 1. Two first straight line parts whose outer peripheries are parallel to each other and facing each other across the center; and the first straight line that is perpendicular to the first straight part and parallel to each other and facing each other across the center. two second straight parts that are shorter than the length of the first straight part, and two second straight parts that are formed from both ends of the second straight parts to a place between the second straight parts and the first straight part, and are opposed to each other with the center in between. A method for manufacturing a stator core for a rotating electric machine, which comprises punching out a plurality of rows of the core, each of which is composed of four third straight portions parallel to each other, from a single strip steel plate.