JPS6380741A - Manufacture of stator core for motor - Google Patents

Abstract

PURPOSE:To eliminate the production of an end material thereby to enhance the yield of a material by forming a ringlike core blank by bending a strip plate in a circular-arc shape, cutting it at each one winding, and then bonding the cut ends to each other. CONSTITUTION:After a base 3 of a striplike continuous core blank in which a toothed part 1 is punched in advance in a developed state in a pectinated shape is wound in a ring shaped on a rotational shaft, it is cut at the center line part of the toothed part 1 at each one winding to obtain a ringlike core blank. After the ringlike core blanks are so flatly pressed to become the state that the cut parts of the blanks are abutted, the abutted parts 9 are bonded. The bonded part 9 is flatly finished to form a ringlike bonded part 10, and a plurality of the bonded parts 10 are laminated while aligning them in a laminating direction.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method of manufacturing a stator core for an electric motor, and particularly to a method of manufacturing a stator core for an electric motor suitable for improving material yield.

[Conventional technology]

The conventional stator core for electric motors is 1, for example,
As shown in Japanese Patent No. 940, a stator core is manufactured by laminating a plurality of Chichishin stacked materials, each of which has its inner and outer periphery and slot portions punched out from a flat plate.

[Problem that the invention seeks to solve]

In the above conventional technology, the stator core is formed by laminating a large number of circularly punched flat steel plates, so the stator core has many edges, which may reduce the yield of the material. Ta.

An object of the present invention is to provide a stator core for a motor with improved material yield.

[Failure to solve the problem]

The above purpose is to form a ring-shaped iron core material by forming a band-shaped plate having teeth at one end and a base at the other end, and rolling and bending the base so that the plate thickness gradually decreases from the inner circumference to the outer circumference. a step of cutting the ring-shaped core material one roll at a time; a step of joining the four cut sections of the ring-shaped core material to form a ring-shaped joined body; and a step of stacking and fixing a plurality of the ring-shaped joined bodies. This is achieved by the steps of:

[Effect]

When the base is rolled so that the thickness gradually decreases from the inner circumference to the outer circumference, the thickness is reduced in the length direction from the thicker end on the inner circumference side to the thinner end on the outer circumference side of the base. The length of the extension will vary. Therefore, the strip plate is bent into an arc shape and formed into a ring-shaped core material. The ring-shaped core material is cut one turn at a time, and the cut ends of the rear limb ring-shaped core material are joined together. As a result, the stator core does not have edges, and it is possible to obtain a stator for an electric motor with a high material yield.

〔Example〕

Below, the present invention will be described in Figures 1, 2, 3, 4, and 5.
This will be explained with reference to the embodiment shown in FIGS.

FIG. 1 is a perspective view of a stator core completed by the manufacturing method of the present invention, FIG. FIG. 5 is a perspective view of the core material, FIG. 5 is a perspective view showing a stacked state of ring-shaped joined bodies, and FIG. 6 is a partial sectional view of a stator core fabricated by the manufacturing method of the present invention. In the figure, the base 3 of a strip-shaped continuous core material 2 is shown, in which the teeth 1 have been developed and punched out in a comb-shape.

Using a plurality of rolls consisting of a combination of a spindle roll 4 and a rolling pan 5, after winding the rotary shaft 6 in a ring shape while diagonally rolling and bending, each winding is performed at the center line of the teeth. disconnect.

In this way, the strip-shaped continuous core material is bent from the inner periphery of the base 3 to the outer periphery with a sequentially large rolling ratio, resulting in a good ring without green liquid on the inner and outer peripheries or cracks on the outer periphery. This has the effect that a shaped iron core material can be obtained.

Figure 4 shows a ring-shaped core material 7 cut in a rolled state.
In the perspective view, the cut portions 8, 8' of the ring-shaped core material 7 are shown.
After pressing and molding them flat so that they are butted, the abutted portions are joined by a suitable method such as electric welding.

As shown in FIG. 5, the joint portion 9 is finished flat to form a ring-shaped joined body 10, and a plurality of ring-shaped joined bodies 10 are stacked as shown in the same figure while aligning the tooth portions of the ring-shaped joined body 10 in the stacking direction.

In this case, the reason why the joint part is the center line of the tooth part is to avoid disturbing the flow of magnetic lines of force when used as a stator core.

If a core with very high dimensional accuracy is required, use the ring-shaped contact body 1.
After forming 0, it is possible to punch out again using a cutting die with the necessary precision with the minimum amount of machining allowance, and then to stack the sheets.

In addition, at the stage of the glue/glue-like joint in FIG.

It is convenient to form the outer circumference of the ring-shaped joined body by punching it out.

Furthermore, since part of the insulation coating previously applied to the core material is destroyed by welding, etc., the slots 11 adjacent to the joints are removed so that the joints 9 do not overlap in the stacking thickness direction, as shown in Fig. 5. By shifting and stacking one slot or multiple slots at a time.

An increase in eddy current loss can be prevented.

Next, stack the ring-shaped joined bodies as shown in Figure 5.

Into the fixing notch 13, insert a rectangular wedge 14 in the shape of a chevron as shown in an example in FIG.

By pressing and fixing 14b, the electric motor stator of the present invention is completed.

Partially enlarged sectional views of the electric motor stator of the present invention completed as described above are shown in FIGS. 6(a) and 6(b).

By changing the rolling bending conditions as necessary.

The base portion may be rolled on either one side or both sides, and in either case, a gap portion 16 is formed by stacking the rolled portions 15. This gap serves to prevent metal contact between overlapping core materials at the portion where the insulating film is broken due to rolling bending, and therefore has the effect of reducing the increase in eddy current loss.

〔Effect of the invention〕

According to the present invention, it is possible to obtain a stator core for a motor with a high material yield without the occurrence of stator core ends.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a stator core completed according to an embodiment of the present invention, FIG. 2 is a perspective view of a wedge used in a stator manufactured according to the present invention, and FIG. 3 is a perspective view of a wedge manufactured according to the present invention. Fig. 4 is a perspective view showing one roll of ring-shaped core material produced according to the present invention, and Fig. 5 is a diagram showing a state in which a strip-shaped core material is rolled and surface-bent by the method. Fig. 6 is a perspective view showing the stacked state of the joined body, and Fig. 6 is a partial cross-sectional view of the stator core manufactured according to the present invention. be. DESCRIPTION OF SYMBOLS 1... Teeth, 2... Strip-shaped continuous core material, 3... Base, 4... Spindle roll, 5... Rolling pan, 6... Rotating shaft, 7... Ring-shaped core Material, 8.
8'... Cutting part, 9... Joining part, 10... Ring-shaped joined body, 11... Slot part, 12... Refrigerant passage, 13... Fixing notch. 14... Wedge, 15... Rolled part, 16... Gap part.

Claims (1)

[Claims] 1. Forming a ring-shaped core material by rolling and bending the base of a band-shaped plate having teeth at one end and a base at the other end so as to gradually reduce the plate thickness from the inner circumference to the outer circumference; A step of cutting the ring-shaped core material one roll at a time, a step of joining the cut ends of the ring-shaped core material to each other to form a ring-shaped joined body, and a step of stacking and fixing a plurality of the ring-shaped joined bodies. A method of manufacturing a stator core for an electric motor, comprising: