JPS605709Y2 - motor rotor - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a rotor for a motor, and more particularly to a rotor in which a rotor core and a shaft are fixed with adhesive.

The rotor of a motor, especially the rotor of a hybrid type step motor, is made up of a shaft 1, a core 2, and a magnet 3, as shown in the first diagram, and each part is fixed by press-fitting the core into the shaft with a tight fit, or by press-fitting the core into the shaft. They were either fitted with a loose fit and fixed with adhesive, or each part was fixed by die-casting.

However, when the press-fitting and die-casting operations described above are performed, various deformations (shaft curvature, eccentricity, etc.) are likely to occur, even if only slightly.Motor rotors, especially step motor rotors, require extremely high precision, so correction machining is necessary. In addition, when adhesive is used, the adhesive often naturally flows out to the outer surface of the shaft (location A), or is extruded and hardened due to expansion during heating, requiring a troublesome removal process. If it is unbalanced, the stress during curing may cause harmful deformation to the shaft, etc. Also, if the shaft 1 and core 2 are tightly fitted to prevent leakage at point A, the adhesive may Although it has high performance, if it is a high-temperature curing type, the adhesive expands and hardens at high temperatures, penetrating between the laminated layers 4 (B, etc.) of the laminated core 2 and expanding it, or expanding the gap C between the core 2 and the magnet 3. Also, when applying the adhesive and assembling each part, air bubbles caught in the adhesive or between the above-mentioned parts are likely to remain trapped and spread. Conventionally, there have been various disadvantages such as reduced reliability.

In consideration of the above, the present invention has produced an excellent rotor using an adhesive method without the above-mentioned various disadvantages, and is particularly characterized by arranging a porous washer (collar) on the outside of the rotor. 4 is a sintered alloy having air permeability and adhesive permeability (in some cases, a hard felt or air permeable sponge-like body, or a porous sintered heat-resistant plastic). A washer (or collar) is fitted on the shaft 1 in contact with the outer surface of the core 2 (which can also be used from the body, etc.), 21 is a rivet for binding the core 2, and 11 is a rivet for binding the shaft 1 - core 2 - magnet 3. Adhesive applied between (not shown)
In order to at least temporarily fix the positional relationship between the shaft 1 and the core 2 without using a special holding jig or the like until the shaft 1 and the core 2 harden, only the core 2 side portion of the inner diameter surface of the washer 4 and the core 2 are attached. This is a parallel knurled portion that is applied over an area I on the shaft 1 so as to come into pressure contact with the inner diameter surface of the shaft 1.

Since the present invention is constructed as described above, even if the applied adhesive flows out or is pushed out from inside the rotor along the shaft 1, it will not bulge up on the part corresponding to A in FIG. 11 and are successively absorbed into the washer 4 along with the air bubbles, so that no buildup of the adhesive is caused on the shaft surface A', and the air bubbles are removed from the washer 4 and released. This prevents problems such as increasing the pressure inside the rotor and the expansion of bubbles (so even when the adhesive is of a high-temperature curing type, there is no problem of pressure spreading between the core laminations or between the core magnets as in the past). A rotor for a step motor that is reliable, has excellent performance, and is manufactured by using a relatively simple means such as the washer 4 and is installed using a relatively simple means such as the washer 4. was provided.

FIG. 3 shows the embodiment shown in FIG. 2, that is, the washer 4 in the first embodiment (FIG. 2) is replaced with a washer 41 in which an adhesive absorption space 42 is additionally recessed in the portion facing the core 2. If it is necessary or effective, add core 2 and magnet 3.
Appropriate pores 22 are provided in the core 2 to allow the adhesive and air bubbles that accumulate or are extruded near the joint surface of the core 2 to escape to the space 42 or the washer 41.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a conventional rotor, and FIGS. 2 and 3 are partial cross-sectional views of a rotor according to a first embodiment and a second embodiment of the present invention, in which 1 indicates a shaft 2, a core; 3 is a magnet, 4.14 is a porous washer, 11 is a knurling, and 22 is a pore.

Claims (1)

[Scope of utility model registration request] A porous body having air permeability and adhesive permeability is disposed on the outer end surface of the rotor core into which the shaft having parallel knurls is inserted, and is fitted onto the shaft, and is arranged between the shaft and the rotor core. A motor rotor configured to be bonded with an applied adhesive so that a portion of the adhesive penetrates into the porous body via the parallel knurls.