JPH0530691A - Stator core - Google Patents

Abstract

PURPOSE:To reduce preparatory work in a pressing process by fixing together two laminated core plates by attaching the projected portions and fitting holes of one core plate to the mutually corresponding fitting holes and projected portions of the other core plate. CONSTITUTION:In a laminated core 1, there are a plurality of projected portions 4 and fitting holes 5 to be fitted to the projections respectively at the equal intervals in the same direction on a circle at the symmetrical positions about the center of the core. When two laminated cores 1A and 1B are fixed back-to- back so that respective magnetic pole portions 3 are projected out in opposite directions, the projected portion of 4A of the core 1A is fitted to the fitting hole 5B of the core 1B, and the fitting hole 5A of the core 1A is fitted to the projected portion 4B of the core 1B each other, thereby fixing the cores 1A and 1B together. As stated above, the laminated core is fixed together by using the cores 1A and 1B of the same shape, so that only one kind of press dies are needed for fixing the laminated cores. By doing this, the preparatory work for pressing process can be simplified considerably.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stator core of a flat type motor used in a floppy disk drive or the like.

[0002]

2. Description of the Related Art Conventionally, the stator core of a flat motor is
As shown in FIG. 2, two laminated cores 1 made of ring-shaped thin steel plates are laminated, and the tips of the teeth 2 provided on the outer circumferences of the two laminated cores 1 are bent in the opposite axial directions to protrude. The magnetic pole portion 3 is formed to increase the magnetic pole area facing the rotor. In this case, in order to fix the laminated laminated cores 1 to each other, one laminated core 1A is provided with a half-blanked or V-shaped protrusion 4 in the axial direction in the protruding direction of the magnetic pole portion 3, and the other laminated core 1A. 1B is provided with a protrusion 4 in a direction in which the magnetic pole portion 3 does not protrude, and a recess 4 formed behind the protrusion 4 of one laminated core 1A and the protrusion 4 of the other laminated core 1B.
The two laminated cores 1A and 1B are fixed by engaging with each other. Also disclosed is one in which a protrusion is provided on one laminated core and an engagement hole is provided on the other laminated core, and the protrusion is engaged with the engagement hole to fix two laminated cores. (For example, Japanese Utility Model Laid-Open No. 64-54744).

[0003]

However, in the above structure, it is necessary to process two kinds of laminated cores, one having two kinds of protrusions or one having a protrusion and an engaging hole. Since the press die of No. 2 is prepared and processed in a separate process, the equipment cost is high, and the number of setup steps of the processing work is increased, resulting in an increase in cost. It is an object of the present invention to reduce the cost of a stator core by using one type of laminated core.

[0004]

SUMMARY OF THE INVENTION According to the present invention, a plurality of teeth are provided on the outer circumference, and the outer circumference of the teeth is formed by laminating two ring-shaped thin steel plates each having a magnetic pole portion bent to project in the axial direction. In a stator core in which the cores are laminated and fixed so that the magnetic pole portions project in axial directions opposite to each other, the stator cores are arranged symmetrically with respect to the center of the laminated core, and are arranged in the same direction at equal intervals on the same circumference. Providing a plurality of protruding portions and engaging holes that can engage with the respective protruding portions are alternately arranged on the circumference, and the protruding portions and the engaging holes of one of the laminated cores are provided. The engaging hole and the protrusion of the other laminated core are engaged with each other.

[0005]

The protrusion of one laminated core and the engaging hole of the other laminated core are engaged with each other, and the engaging hole of one laminated core and the protrusion of the other laminated core are engaged with each other to form two sheets. Since the laminated core of is fixed, it is possible to fix two laminated cores of the same shape back to back so that the magnetic pole parts project to the opposite side, and there is only one type of press die for processing the fixed part. Well, it is possible to reduce the setup work for press working.

[0006]

Embodiments of the present invention will be described with reference to the drawings.
FIG. 1A is a plan view showing an embodiment of the present invention, and FIG. 1B is a side sectional view taken along the line SS of FIG. 1, in which a plurality of teeth 2 are provided on the outer periphery of a ring-shaped laminated core 1 made of a thin steel plate. Is provided, and the magnetic pole portion 3 is bent on the outer periphery of the tooth 2 so as to project in the axial direction. The laminated core 1 is provided with a plurality of protrusions 4 protruding in the same direction at equal intervals on the same circumference at positions symmetrical to the center, and engagement holes 5 capable of engaging with the respective protrusions 4. They are provided so that they are alternately arranged on the circumference. When the two laminated cores 1A and 1B are fixed back-to-back so that their magnetic pole portions project to opposite sides, the laminated core 1A
Of the laminated core 1B and the engaging hole 3 of the laminated core 1B are engaged with each other, and the engaging hole 3 of the laminated core 1A and the protruding portion 2 of the laminated core 1B are engaged with each other to fix the laminated cores 1A and 1B. There is. As described above, since the laminated cores 1A and 1B having the same shape are fixed to each other, only one type of press die for processing the fixed portion is required, and the setup work of the press processing can be reduced.

[0007]

As described above, according to the present invention, 2
There is only one type of processing die that forms the fixed portion of the laminated core, and there is an effect that equipment cost and work man-hours can be reduced.

[Brief description of drawings]

FIG. 1A is a plan view showing an embodiment of the present invention.

FIG. 1 (b) is a side sectional view taken along the line S-S shown in FIG.

FIG. 2 is a side sectional view showing a conventional example.

[Explanation of symbols]

1, 1A, 1B Laminated core 2 Teeth 3 Magnetic pole part 4, 4A, 4
B protrusion 5, 5A, 5B engaging hole

Claims (1)

Claim: What is claimed is: 1. A plurality of teeth are provided on the outer circumference, and two ring-shaped laminated cores made of thin steel plates are formed on the outer circumference of the teeth, the magnetic poles being bent so as to project in the axial direction. In a stator core in which the magnetic pole portions are laminated and fixed so as to project in axial directions opposite to each other, the magnetic pole portions project in the same direction at the same position on the same circumference at symmetrical positions with respect to the laminated core. A plurality of protrusions and engagement holes that can be engaged with the respective protrusions are provided so as to be arranged alternately on the circumference, and the protrusions and the engagement holes of one of the laminated cores are provided on the other side. A stator core, wherein the engaging hole and the protrusion of a laminated core are engaged with each other.