JPS63124736A - Rotor for motor - Google Patents

Abstract

PURPOSE:To obtain a rotor for a motor, high in the dimensional accuracy of a yoke and a permanent magnet, by a method wherein the rotor is provided with the cylindrical magnet, arranged on the outer periphery of a sleeve, and reinforcing members, provided on the outer periphery of flanges provided above and below the magnet. CONSTITUTION:A rotary shaft is connected to the connecting part 5 of a sleeve 1 by press fitting or the like. The sleeve 1 is provided with annular grooves 6, 6' at the upper and lower parts thereof. Flanges 3, 3' are provided with stepped parts 7 on the inner peripheral sides thereof. A cylindrical magnet 2 is fitted to the sleeve 1, thereafter, the flanges 3, 3' are fitted to the sleeve 1 from the upper and lower sides of the magnet so as to pinch the magnet 2. Pushing edges inserted into gaps 8, 8', generated between the upper and lower ends of the sleeve and the stepped parts in the flanges, to press the flanges in the direction of up-and-down whereby one parts of flanges are deformed and flows into the annular grooves 6, 6' on the sleeve, therefore, the flanges 3, 3' are connected to the sleeve 1 strongly through caulking.

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 improving assembly ease.

[Conventional technology]

Conventionally, the structure of the rotor of a permanent magnet electric motor is as shown in, for example, 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 magnet τ, it can be absorbed by the aluminum die-casting, and that the balance weight portion can be molded at the same time using the die-casting shape.

[Problem that the invention attempts to solve]

Regarding the assemblability of the upper and lower conventional technologies, it is necessary to assemble the yoke and permanent magnet using adhesive before putting them into the die-casting mold, and because the yoke and permanent magnet are affected by the heat of die-casting, the yoke and permanent magnet There was a problem that it was difficult to obtain dimensional accuracy.

An object of the present invention is to provide a rotor for an electric motor in which the yoke and the permanent magnet have high dimensional accuracy.

[Means for solving problems]

The above purpose is to provide a sleeve that is coupled to a rotating shaft of an electric motor, a cylindrical magnet placed on the outer periphery of the sleeve, a flange provided above and below the magnet, and a cylindrical magnet placed on the outer periphery of the magnet and the flange. This is achieved by comprising a reinforcing member tube provided.

[Effect]

The adhesion process and die-casting process before die-casting are eliminated, and assembling efficiency is greatly improved, and dimensional accuracy is also improved because the influence of heat during die-casting is eliminated.

A permanent magnet provided on the outer periphery of the sleeve is fixed together with the flange by a reinforcing member tube. This eliminates aluminum die-casting, which may be due to heat effects during aluminum die-casting (which results in a motor rotor with good dimensional accuracy.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 to 4. In FIG. 1, 1 is a sleeve made of steel, 2 is a cylindrical ferrite magnet, 3.3' is a flange made of a non-magnetic material, and 4 is a reinforcing member tube made of a non-magnetic material. The sleeve 1 has a connecting portion 5 with a rotating shaft (not shown) in its narrow part, and the rotating shaft is connected to the connecting portion 5 by press fitting or the like.

At the top and bottom of the sleeve 1 are annular grooves 6.6 as shown in FIG.
', and the flange 3.3' is provided with a stepped portion 7 on its inner circumferential side, as shown in FIG.
As shown in Figure 1 (after the cylindrical magnet 2 is inserted into the sleeve 1, the flanges 3 and 3' are inserted from above and below to sandwich the magnet, and the outer periphery of the upper and lower ends of the sleeve and the stepped part of the inner periphery of the flange A push blade (not shown) is inserted into the gap 8.8' created between the 6.6', and the sleeve l and flange 3.3' are firmly caulked together.

In the above-mentioned connection, in principle, a good connection can be obtained by using a softer material for the flange than the material for the sleeve. In the case where the sleeve was made of steel as in this example, good bonding was obtained regardless of whether the flange was made of aluminum and aluminum alloy, zinc and zinc alloy, or copper and copper alloy. However, when mild steel, which is a magnetic material, is used, magnetic leakage from the flange increases, which is not desirable in terms of performance.

Further, the shape of the annular grooves on the upper and lower sides of the sleeve shown in Fig. 2 6.6' can be any shape as long as it produces a wedge effect of the inflowing metal and compressive residual stress. In addition to shaped grooves, the same caulking effect was obtained with square grooves, circular grooves, etc. The number of grooves can be selected from a single groove or a plurality of grooves, taking into consideration the strength and workability of caulking.

The upper and lower end surfaces of the cylindrical magnet 2 are provided with radial notches 9 and 9' as shown in FIG. 4, and the negative flange is provided with a projection 10 as shown in FIG. 3 on the magnet side. and
When the magnet is held between the above flanges from above and below, a fitting portion between the protrusion and the groove is formed, and slippage between the sleeve and the magnet during rotation is prevented.

Furthermore, the flange is marked with kl in Figs. 1 and 3.

As shown in 11', by providing the balance weight part integrally, it is possible to reduce the number of parts and improve assembly efficiency. Any method such as machining, casting, forging, die-casting, etc. can be used to process the 2-lunge, but if the balance weight part is provided integrally, the reinforcing member shown in Fig. 1 4 will have a complicated shape. The tube is made of a thin non-magnetic material to prevent fragments from scattering in the event that the ferrite magnet is damaged. The purpose of using a non-magnetic material for the reinforcing member tube is to prevent magnetic leakage. In this example, a stainless steel thin-walled tube was press-fitted and fixed.

According to this embodiment, the cylindrical magnet and flange are inserted from above and below in the axial direction of the sleeve, compressed from above and below, and then press-fitted in the axial direction, so that the entire assembly process can be completed by one-way assembly. This greatly improves the mechanical strength of the rotor, makes it easier to assemble automatically, and makes it possible to manufacture high-performance permanent magnet rotors at low cost.

Furthermore, compared to conventional rotors assembled by die-casting, there is no heat effect from high temperatures, resulting in a significant improvement in dimensional accuracy.

〔Effect of the invention〕

According to the present invention, it is possible to provide a rotor for an electric motor with high dimensional accuracy.

FIG. 1 is a longitudinal sectional view of an embodiment of the present invention, FIG. 2 is a perspective view of a sleeve, FIG. 3 is a perspective view of a permanent magnet, and FIG. 4 is a perspective view of a flange.

DESCRIPTION OF SYMBOLS 1... Sleeve, 2... Magnet, 3.3'... Flange, 4... Reinforcement member tube, 5... Joint part, 6.6'
...Annular groove, 7...Step part, 8.8'...Gap part, 9.9'...Notch part,], O...Protrusion part, LL
, ll'...Balance weight y: 10
Kaya 20

Claims (1)

[Claims] 1. A sleeve coupled to the rotating shaft of the electric motor, a cylindrical magnet placed on the outer periphery of the sleeve, a flange provided above and below the magnet, and a cylindrical magnet provided on the outer periphery of the magnet and the flange. A rotor for an electric motor, comprising a reinforcing member tube.