JPS5992753A - Permanent magnet rotor type synchronous motor - Google Patents

Abstract

PURPOSE:To prevent an adhesive from extending out by splitting a permanent magnet rotor, and forming a stepped part which forms an extension preventive adhesive reservoir on the entire outer peripheral edge of the adhered surface. CONSTITUTION:A bobbin 2, on which a drive coil 3 is wound, is mounted on a stator core 1. A permanent magnet rotor 5 is disposed between poles 4a and 4b. The rotor 5 is formed of members 5a, 5b axially split and a shaft 6 of a central part, and integrated with an adhesive. A stepped part 9 which forms an extension preventive adhesive reservoir is formed on the entire outer periphery of the adhered surface of the members 5a, 5b, thereby preventing the adhesive from extending out.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a permanent magnet rotor type synchronous motor used as a drive source for devices such as small orange squeeze juicers.

Conventional Structure and Problems Conventionally, sintered ferrite magnets have been mainly used as permanent magnet rotors in this type of electric motor. However, this sintered magnet is made into a cylindrical shape through oriented press molding, firing, etc., and it is expensive in itself, such as polishing the outer shape, and it also requires integral molding of the shaft insert resin. The injection molding pressure applied inside the cylinder of the sintered magnet often causes defects such as cracking of the sintered magnet, so consideration was required before it could be used as a permanent magnet rotor.

OBJECTS OF THE INVENTION The object of the present invention is to provide an inexpensive permanent magnet rotor type synchronous motor that eliminates the drawbacks of the conventional motor.

Structure of the Invention The permanent magnet rotor of the present invention is a resin magnet. However, in this case, magnetic field orientation is required during injection molding. 1st
In the case of a disc-shaped resin magnet used for the stator magnet of a flat motor as shown in the figure, the orientation direction A is the thickness direction, so the orientation magnetic pole gap is small and sufficient orientation can be achieved. In the case of a rotor made of magnets, since they are oriented in the B direction, that is, in the radial direction, the oriented magnetic pole air gap becomes large, and unless a large molding machine larger than that required for the injection capacity is used, the oriented magnetic poles cannot obtain sufficient magnetic field orientation. In addition, since the magnetic flux density of resin magnets is lower than that of sintered ferrite magnets, it is necessary to increase the volume of the magnet, that is, the diameter and length, to compensate for the deficiency, and this also increases the magnetic pole gap. This is a factor that increases the size. Therefore, in response to an increase in diameter, the rotor can be molded and oriented in a half-split shape in the axial direction, and sufficient orientation can be obtained with an appropriate molding machine. Then, these half molded pieces are integrated with an adhesive with a shaft located in the center. At this time, in order to prevent the adhesive from oozing out from the adhesive surface to the outer periphery, a stepped portion is formed on the outer periphery of the adhesive surface to form an adhesive reservoir 9 for preventing the adhesive from oozing out.

Description of examples An embodiment of the configuration of the present invention will be described based on the drawings.

In FIG. 2, 1 is a stator core, and 2 is a bobbin around which a drive coil 3 is wound, which is attached to the stator core 1. 4
Numerals a and 4b are magnetic pole parts, and a permanent magnet rotor 5 is arranged between these magnetic pole parts. This rotor 5 is a resin magnet formed by mixing ferrite powder and resin and injection molding the mixture, and consists of members SA, TSB, which are divided in half in the axial direction, and a shaft 6 in the center, which are bonded together. be done. FIG. 3 is a perspective view of the integrated rotor 5, FIG. 4 is a perspective view of the rotor divided into halves, and FIG. 4 and FIG. 5 are details thereof.
is a concave groove into which the shaft 6 is attached, 8a and 8b are mating surfaces for adhesion, and 9 is a lower step formed around the entire outer edge of the mating surfaces 8a and sb. The excess amount of the applied adhesive is held in the extrusion-preventing adhesive reservoir formed by this stepped portion 9, and is prevented from extruding to the outer periphery.

Effects of the Invention As described above, the present invention divides a permanent magnet rotor into halves, and when joining them together with adhesive, a stepped portion is formed around the entire outer edge of the adhesive surface to serve as an adhesive reservoir to prevent extrusion. This prevents the adhesive from seeping out, and provides a synchronous motor that employs an inexpensive permanent magnet rotor.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of a disc-shaped resin magnet used in flat motors, etc., Fig. 2 is a partial sectional view of a permanent magnet rotor type synchronous motor showing an embodiment of the present invention, and Fig. 3 is the same as Fig. 2. FIG. 4 is a perspective view of the permanent magnet rotor, FIG. 4 is a perspective view of the rotor divided shape, and FIG. 6 is an enlarged perspective view of the main part of FIG. 4. 1... Stator core, 3... Drive coil, 4a. 4b... Magnetic pole part, 5a, sb... Divided rotor, 6... Shaft, 8a, 8b...
・Matching surface, 9...Stepped part. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 4 Q Figure 5 Fever. 5 years

Claims (1)

[Claims] A permanent magnet rotor is placed between the magnetic poles of the stator core equipped with the drive coil, and this rotor is made of resin magnets and is divided into halves in the axial direction, with a lower step part around the entire outer edge of the mating surface. A permanent magnet is provided with a concave groove in the center for mounting the shaft, and is integrated with an adhesive on the mating surfaces, and the stepped part serves as an adhesive reservoir to prevent adhesive from coming out. Rotor type synchronous motor.