JPS62203538A - Rotor for motor - Google Patents

Abstract

PURPOSE:To accurately and simply secure a cylindrical magnet to a core by compressing a ring in the axial direction of the core and holding the magnet by a flange and a washer. CONSTITUTION:A flange 1a is integrally formed as an axial removal preventing mechanism at one side of a core 1, and an aluminum ring 2, a cylindrical magnet 3, an aluminum ring 4 and a steel plate washer 5 are associated from the opposite side of the flange 1a. After the association is completed, a cutout washer 6 is inserted to a groove 10 formed on the core as a washer 5 removal preventing mechanism in the axial direction opposite to the flange. After the association, the ring 2 is so compressed radially until the plastic flow of a material occurs so that the magnet 3 interposed between the flange 1a of the core 1, the washer 6 and the washer 5 is fixed by the axial compression stress.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a rotor for an electric motor, and particularly to a rotor for an electric motor suitable for fixing cylindrical permanent magnets.

[Prior art]

Conventionally, the structure of the rotor of a permanent magnet type synchronous electric plate is as follows.
For example, as shown in Japanese Utility Model Application Publication No. 59-097588, a yoke made of laminated steel plates, a permanent magnet, and a surface reinforcing material are combined by aluminum die casting.

This structure has the advantage that even if there is some dimensional variation in the permanent magnets, it can be absorbed by the aluminum die-casting, and that the balance weight part can be molded into the die-cast shape at the same time.

[Problem that the invention seeks to solve]

The above conventional technology requires that the yoke and permanent magnet be assembled using adhesive before being placed in the die-casting mold.
In order to prevent the die-casting material from entering between the surface reinforcing member and the wall of the die-casting mold, it is difficult to make the surface reinforcing material too thin, and it is difficult to obtain precision due to the thermal effects of die-casting. There were some problems.

An object of the present invention is to provide a rotor for an electric motor in which a cylindrical magnet can be precisely and easily fixed to an iron core.

[Means for solving problems]

An object of the present invention is to provide an iron core having a flange at one end, a cylindrical magnet inserted on the outer periphery of the iron core, a ring inserted between the cylindrical magnet and the flange, and a cylindrical magnet inserted on the outer periphery of the other end of the iron core. This is achieved by compressing the ring in the axial direction of the iron core and sandwiching the cylindrical magnet between the flange and the washer.

A flange is integrally provided on one side of the core as a mechanism to prevent axial removal, and the aluminum ring, cylindrical magnet, aluminum ring, and steel plate washer are assembled from the opposite side of the flange. It will be done. After the assembly is completed, a washer with a notch is inserted into the groove 10 provided in the iron core,
This serves as a mechanism to prevent the washer from being removed in the axial direction opposite to the flange.

All of these parts are assembled with gaps for easy assembly. After assembly, the aluminum ring is compressed in the radial direction from the outer periphery until plastic flow of the material occurs, so that the flange of the iron core, the notched washer, and the cylindrical magnet sandwiched between the washer are compressed in the axial direction. It is fixed by the compressive stress of .

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2. In Fig. 1, 1 is an iron core made by cutting cast iron, 2 is an aluminum ring, 3 is a cylindrical ferrite magnet, 4 is an aluminum ring, 5 is a steel plate washer, and 6 is an axially punched core. This is a washer with a notch made of steel plate as a preventive structure. The iron core 1 has a coupling part 9 with a rotating shaft (not shown) in the axial center, and the rotating shaft is coupled to the coupling part 9 by press-fitting or the like.

A flange 1a is integrally provided on one side of the iron core 1 as a mechanism for preventing axial removal, and an aluminum ring 2, a cylindrical magnet 3, an aluminum ring 4, and a steel plate washer 5 are provided on the opposite side of the flange 1d. Incorporated from. After the assembly is completed, the notched washer 6 is inserted into the groove 10 provided in the core, and serves as a mechanism to prevent the washer 5 from being removed in the axial direction opposite to the flange. All of these parts are assembled with gaps for easy assembly. After assembly, the aluminum ring 2 is compressed radially from the outer periphery until plastic flow of the material occurs, thereby creating a cylindrical magnet sandwiched between the flange 1a of the iron core 1 and the notched washers 6 and 5. 3 is fixed by the action of compressive stress in the axial direction. The washer 5 is made strong enough to prevent large deformation at the cutout portion of the washer 6. The flange 1a of the iron core 1 is provided with a groove 7 for the aluminum ring 2 to be compressed to flow into it and to strengthen the fixation, but such a device can be applied to other washers as necessary. I can do it. In FIG. 2, the axial blank area shows the shape of the prevention washer 6. The connecting portion 9 and the eccentric hollow portions 11 and 12 shown in FIG. It's something I've saved up. The reinforcing member tube 8 is attached as necessary depending on the strength of the magnet, the number of rotations of the rotor, etc.

According to this embodiment, an inexpensive cast iron iron core 1 and an inexpensive cylindrical ferrite magnet 3 with low tensile strength but high compressive strength and strong magnetic force can be assembled automatically, resulting in a high-performance permanent magnet. A magnet rotor can be manufactured at low cost.

〔Effect of the invention〕

As described above, according to the present invention, the axial compressive force generated by compressing the low-yield-point material ring is made to remain in the axial direction of the cylindrical magnet after the axial pull-out prevention mechanism is assembled. The iron core of the rotor and the magnets can be easily fixed without using an adhesive process or a die-casting process, which has a great effect on reducing the cost of permanent magnet rotors.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a longitudinal cross-sectional view of an embodiment of the present invention, and FIG. 2 is a plan view of one component in the embodiment of the present invention. 1... Iron core, 2... Aluminum ring, 3...
Cylindrical magnet, 4... Aluminum ring, 5... Washer, 6... Notched washer, 7... Groove, 8...
... Reinforcement pipe, 9 ... Shaft coupling part, 10 ... Groove, 11
...hollow, 12...empty/"""-'

Claims (1)

[Claims] 1. An iron core having a flange at one end, a cylindrical magnet inserted on the outer periphery of the iron core, a ring inserted between the cylindrical magnet and the flange, and a washer inserted on the outer periphery of the other end of the iron core. A rotor for an electric motor, characterized in that the ring is compressed in the axial direction of the iron core, and the cylindrical magnet is held between the flange and the washer.