JPH04271255A - Manufacture of magnet for small-sized motor - Google Patents

Abstract

PURPOSE:To elevate and maintain the quality of a motor for a long period by preventing it from causing chips when cutting magnet material. CONSTITUTION:This is manufacture of magnetizing individually after currying it into plural pieces in the condition that chamfered parts 2a1, 2a2, 2a3, 2a4, 2a5, 2a6, 2a7, 2a8, 2b1, 2b2, 2b3, 2b4, 2b5, 2b6, 2b7, and 2b8 are formed at both sides of the cutting parts of a magnet material 2.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a magnet for a small motor, which is used, for example, to form the magnetic flux of an armature in a small motor.

0002

13 to 16 illustrate a method of manufacturing a magnet for a small motor of this type. As shown in FIG. 13, the main component is iron and nickel or cobalt is added to form the magnet. Cutting lines 100a, 1 are cut on the surface of the magnet material 100, which has the shape of a circular cylinder divided into two in the cylindrical direction.
00a, 100a, and as shown in FIG. 14, the cutter 50 performs cutting along the respective cutting lines 100a, 100a, 100a. Then, as shown in Figure 15,
After forming the cut surfaces 110a and 110a on both sides to obtain the divided molded body 110, an N pole (S pole) is attached to the inner peripheral surface and an S pole to the outer peripheral surface of the molded body 110 using a magnetizing jig (not shown). By performing (N-pole) magnetization, as shown in FIG. 16, a magnet 120 fixed to the inner surface of the motor yoke 60 was manufactured.

0003

[Problems to be Solved by the Invention] However, in the above-described conventional method of manufacturing a magnet for a small motor, the cutting lines 100a, 100a, 1 set on the surface of the magnet material 100 are
Since the molded body 11 was manufactured by cutting with the cutter 50 according to the cutter 50,
The edges of the cut surfaces 110a and 110a of 0 are acute angles, so it is difficult to say that there will be no chipping, and if a chip occurs after it is assembled to the motor yoke 60, it may damage the internal mechanism of the motor. There was a problem in that the quality was impaired.

0004

[Object of the Invention] This invention has been made in view of the above-mentioned problems of the prior art.It is a compact machine that reduces the occurrence of chips when cutting, and that allows the quality of the motor to be maintained for a long period of time. The purpose of this invention is to provide a method for manufacturing a motor magnet.

[0005]

[Means for Solving the Problems] A method for manufacturing a magnet for a small motor according to the present invention is a method for manufacturing a magnet in which a magnet material is cut into a plurality of pieces and then magnetized individually, the magnet material being cut into pieces. It is characterized by a configuration in which cutting is performed with chamfered portions formed on both sides of the part, and in embodiments adopted as necessary, the chamfered portion is provided with a molding die provided with an inclined surface for the chamfered portion. It is characterized by a configuration in which cutting is performed on a magnet material formed by molding, and in the same embodiment, a configuration in which chamfered portions are formed by cutting on both sides of the cut portion of the magnet material, and then cutting is performed, and as described above. The structure of the invention relating to a method of manufacturing a magnet for a small motor is a means for solving the above-mentioned conventional problems.

[0006]

[Operation] Since the method for manufacturing a magnet for a small motor according to the present invention has the above-described structure, chamfered portions are formed on both sides of the cut portion of the magnet material to be cut, and the chamfered portions cut the edges of the cut surface. Since the edges are at an obtuse angle, there is less chance of chipping when cutting compared to when the edges of the cutting surface are at an acute angle, so there is no damage to the internal mechanism of the motor due to chipping. Magnets are manufactured.

[0007]

[Embodiment] FIGS. 1 to 6 show an embodiment of the method for manufacturing a magnet for a small motor according to the present invention, in which a pressure-side punch 10 (molding die) and a receiving-side punch 11 are shown.
1 shows a process of manufacturing a magnet 1 using a pressure molding machine 12 (molding machine) equipped with a molding die.

The pressing side punch 10 is provided with a convex portion 10a having a shape obtained by dividing a cylinder into two in the axial direction, and a side wall 10a1 of the convex portion 10a has a semi-annular shape extending toward the outer periphery of the convex portion 10a1. Inclined surfaces 10a2, 10a3 and 10a4, 10a5 and 10a6 for pressure side chamfers, which are inclined to form a
10a7, 10a8, and 10a9 are provided at positions that equally divide the length of the convex portion 10a1 into four.

[0009] The receiving punch 11 is also provided with a recess 11a in the shape of a cylinder divided into two in the axial direction, and a side wall 11a1 of the recess 11a has a semi-annular shape extending toward the inner periphery of the recess 11a1. Slanted surfaces 11a2, 11a3 and 11a4, 11a5 and 11 for receiving side chamfers which are inclined to form an angle
A6, 11a7 and 11a8, 11a9 are provided at positions that equally divide the length of the recess 11a1 into four.

Then, after putting barium oxide (BaO)/iron oxide (6Fe2 O3) powder into the recess 11a of the receiving punch 11, the powder is placed in the convex part 10a of the pressing punch 10.
1 is compression molded to correspond to the recess 11a of the receiving punch 11, and then sintered. As a result, as shown in FIG. 3, a magnet material 2 having a semi-cylindrical shape is obtained, and the outer peripheral surface 2a of this magnet material 2 has semi-annular chamfered portions 2a1 and 2a2 that are inclined toward the inner peripheral side. 2a3, 2a4, 2a5, 2a6, 2a7, 2a8 are formed to divide the length dimension of the magnet material 2 into four, and the inner peripheral surface 2 of the magnet material 2
b, each chamfered portion 2 is inclined toward the outer circumferential side and
Semi-annular chamfered portions 2b1 corresponding to a1 to 2a8, respectively;
2b2 and 2b3, 2b4 and 2b5, 2b6 and 2b7, 2
b8 is formed.

Therefore, the chamfered portions 2a2 and 2a3, 2a4 and 2a5, and 2a6 and 2 which are adjacent to each other on the outer circumferential surface 2a are
Set cutting lines 2c, 2c, 2c at the touching part of a7,
As shown in FIG. 4, cutting is performed with a cutter 50 along the cutting lines 2c, 2c, 2c.

Then, as shown in FIG. 5, by magnetizing the cut molded body 21 with N and S poles, as shown in FIG.
As shown in the figure, a short magnet 1 with a semi-cylindrical shape is used.
On both sides of the outer circumferential wall 1a of this magnet 1 fixed to the inner surface of the motor yoke 60, there are magnet chamfered portions 1d and 1e that are in contact with the cut surfaces 1b and 1c at obtuse angles, respectively.
, and magnet chamfered portions 1g and 1h are provided on both sides of the inner circumferential wall 1f of the magnet 1, respectively, at obtuse angles to the cut surfaces 1b and 1c.

FIGS. 7 to 12 show another embodiment of the method for manufacturing a magnet for a small motor according to the present invention, in which a magnet material 20 formed into a semi-cylindrical shape is cut and then cut. The process of manufacturing the magnet 1 is shown.

In this case, cutting auxiliary lines 20b, 20b, 20b, 20b, 20b that divide the length of the magnet material 20 into four equal parts are set on the inner peripheral surface 20a of the magnet material 20 shown in FIG. Each of the cutting auxiliary lines 20b, 20b, 2
0b, 20b, and 20b are cut using a grinder 51.

Here, the grinder 51 has an outer dimension slightly larger than the inner diameter dimension of the magnet material 20, and has the respective cutting auxiliary lines 20b, 20b, 20b,
20b, a convex inclined tooth portion 51a corresponding to 20b,
51a, 51a, 51a, 51a (the tooth portion 51a on the near side in FIG. 8 is not shown) are formed, and the inclined tooth portions 51a, 51a, 51a, 51a, 51a are used to assist in cutting the magnet material 20. Lines 20b, 20b, 20b, 20b
, 20b and cut to a predetermined cutting dimension, as shown in FIG. Annular chamfered portions 20a1 and 20a2, 20a3 and 2
0a4, 20a5, 20a6, 20a7 and 20a8 are formed. Therefore, as shown in FIG. 10, the cutter 50 performs cutting along each of the cutting auxiliary lines 20b, 20b, 20b, 20b, 20b that are closer to the center.

Then, as shown in FIG. 11, by magnetizing the cut molded body 21 with N and S poles, a short semi-cylindrical magnet 1 is obtained as shown in FIG. The inner peripheral wall 1f of this magnet 1 fixed to the inner surface of the motor yoke 60 has cut surfaces 1b, 1 on both sides.
magnet chamfered portions 1g that are in contact with c at obtuse angles,
1h is provided.

Although the chamfered portion formed on the magnet material 20 in the method for manufacturing a magnet for a small motor according to the present invention is illustrated as a substantially flat surface, the chamfered portion may be a curved surface, and the same applies in that case. Needless to say, this invention can be used for.

[0018]

[Effects of the Invention] Since the method for manufacturing a magnet for a small motor according to the present invention has the above-described structure, chamfered portions are formed on both sides of the cut portion of the magnet material to be cut. Because the edges of the cut surface are obtuse, there is less chance of chipping compared to when the edges of the cutting surface are acute. This brings about the effect that the quality of the motor can be kept high for a long period of time.

[Brief explanation of the drawing]

FIG. 1 is a front view of a pressure molding machine used in an embodiment of the method for manufacturing a magnet for a small motor according to the present invention.

FIG. 2 is a side view of a pressure molding machine used in an embodiment of the method for manufacturing the magnet for a small motor shown in FIG. 1;

FIG. 3 is an external perspective view of a magnet material molded by the method for manufacturing a magnet for a small motor shown in FIG. 1;

4 is a side view showing a step of cutting a magnet material formed by the method of manufacturing a small motor magnet shown in FIG. 1; FIG.

5 is an external perspective view of a magnet manufactured by the method for manufacturing a magnet for a small motor shown in FIG. 1. FIG.

6 is a plan view of a magnet manufactured by the method for manufacturing a small motor magnet shown in FIG. 1. FIG.

FIG. 7 is an external perspective view of a magnet material used in another embodiment of the method for manufacturing a magnet for a small motor according to the present invention.

8 is a perspective view of the appearance when cutting is performed on the magnet material in the method of manufacturing the magnet for a small motor shown in FIG. 7; FIG.

9 is an external perspective view of a magnet material that has been cut as shown in FIG. 8 in the method for manufacturing a magnet for a small motor shown in FIG. 7;

10 is a side view showing a step of cutting a magnet material formed by the method for manufacturing a magnet for a small motor shown in FIG. 7; FIG.

11 is an external perspective view of a magnet manufactured by the method for manufacturing a magnet for a small motor shown in FIG. 7. FIG.

12 is a plan view of a magnet manufactured by the method for manufacturing a small motor magnet shown in FIG. 7. FIG.

FIG. 13 is an external perspective view of a magnet material used in a conventional method for manufacturing a magnet for a small motor.

FIG. 14 is an external perspective view when cutting a magnet material in a conventional manufacturing method of a magnet for a small motor.

FIG. 15 is an external perspective view of a magnet manufactured by a conventional method for manufacturing magnets for small motors.

FIG. 16 is a plan view of a magnet manufactured by a conventional method for manufacturing a magnet for a small motor.

[Explanation of symbols]

1 Magnet 2, 20 Magnet material 2a1, 2a2, 2a3, 2a4, 2a5, 2a6, 2
a7, 2a8, 2b1, 2b2, 2b3, 2b4, 2b
5, 2b6, 2b7, 2b8, 20a1, 20a2, 2
0a3, 20a4, 20a5, 20a6, 20a7, 2
0a8 Chamfered portions 10, 11 (12) Molding mold (
Molding machine) 10a2, 10a3, 10a4, 10a5, 10a6,
10a7, 10a8, 10a9, 11a2, 11a3,
11a4, 11a5, 11a6, 11a7, 11a8,
11a9 Slanted surface for chamfered part

Claims (3)

[Claims] 1. A method for manufacturing a magnet in which a magnet material is cut into a plurality of pieces and then individually magnetized, the magnet material being cut with chamfers formed on both sides of the cut portion. A method for manufacturing magnets for small motors. 2. The magnet for a small motor according to claim 1, wherein the magnet material formed with the chamfered portion is cut using a molding die provided with an inclined surface for the chamfered portion. Production method. 3. The method of manufacturing a magnet for a small motor according to claim 1, wherein the cutting is performed after chamfers are formed on both sides of the cut portion of the magnet material by cutting.