JPS5961458A - Magnet rotor - Google Patents

Abstract

PURPOSE:To prevent a sintered permanent magnet from cracking and to eliminate the removal of a shaft by integrating the cylindrical magnet and the shaft via thermosetting resin. CONSTITUTION:A cylindrical sintered permanent magnet 1 is mounted in a circular hole B of a jig A, a shaft 3 is inserted into the central hole C concentric with the hole B, and a cover 4 is coated. Then, the shaft 3 is inserted between the magnets 1, and resin 2 is filled from an inlet 5. After the resin 2 is filled, it is geled at 50-100 deg.C for 30-60min, and completely cured at 100-150 deg.C for 30-60min. Thereafter, the resin is cooled to the ambient temperature, the jig A is disassembled, and removed.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnet rotor, and particularly to a magnet rotor that is easy to assemble and in which a cylindrical sintered permanent magnet and a shaft do not separate.

For a magnet rotor, it is important to determine how the shaft is fixed and covered with a cylindrical sintered permanent magnet. Conventionally, an aluminum bushing is interposed between the cylindrical permanent magnet and the shaft and bonded with adhesive. Alternatively, it is fixed between the cylindrical permanent magnet and the shaft by injection molding, die casting, or the like. However, such assembly work requires a large number of man-hours and processes, and the molding and molding costs are relatively high, and there are also drawbacks such as the cylindrical permanent magnet cracking due to the pressure during molding. .

SUMMARY OF THE INVENTION An object of the present invention is to eliminate the above-mentioned drawbacks and to provide a magnet rotor that does not cause cracking of the sintered permanent magnets and does not cause the shaft to come off.

The present invention provides a magnet rotor using cylindrical sintered permanent magnets, in which a shaft is provided at the center of the inner side of the cylindrical sintered permanent magnet, and the shaft is connected to the permanent magnet 6 with high adhesive strength. It is molded and integrated with thermosetting resin.

However, in the above molding method, if a filler such as talc calcium carbonate is simply added to the conventional thermosetting resin, the adhesive strength may be lost due to the balance between the adhesive strength of the thermosetting resin and the shrinkage stress during molding. This can be avoided to some extent by increasing the ratio of feeler material to reduce shrinkage, but increasing the amount of feeler material causes problems such as a decrease in adhesive force itself and a decrease in castability. Ta.

Therefore, it is an object of the present invention to reduce the shrinkage of resins during thermosetting. The method is to apply a slight pressure during thermosetting of the resin, and to add a ceramic balloon such as a glass balloon or a glass balloon as a filler A.

Since these ceramic balloons have a space inside, this space effectively absorbs the overall shrinkage during heat curing and cooling, thereby controlling the shrinkage that occurs at the bonding interface and improving bond strength. You can stir it.

In fact, after the resin is injected into the mold, internal pressure is generated in the -C1 mold due to the large expansion of the ceramic balloon during thermal curing. By adopting a mold structure, it is possible to harden while applying the above-mentioned slight pressure, and the shrinkage of the resin during cooling can be absorbed by the expansion of the balloon, thereby reducing the amount of resin. It is.

Embodiments of the present invention will be described below based on the drawings.

Embodiment 1 FIGS. 1(a) and 1(b) are a side view and a vertical sectional view showing an embodiment of a magnet rotor according to the present invention, in which 1 is a cylindrical sintered permanent magnet (hereinafter referred to as cylindrical magnet 6). ), 3 is a shaft, and 2 is a resin for fixing and covering the cylindrical magnet 1 and the shaft 2. The resin 2 hardens to form the cylindrical magnet 1 and the cylinder 1? It is integrated with the foot 3 and is molded as a magnet rotor.

To assemble the above magnet rotor, as shown in Fig. 2, first place the cylindrical magnet 1 in the circular hole B of the jig A, and then insert the cylindrical magnet 1 into the central hole C concentric with the circular hole B. Put on lid 4. Next, resin 2 is injected between the shaft 3 and the cylindrical magnet 1 through the injection port 5. 50~ after injecting the resin 2 to be degassed from the deaeration port 6
100-15 after gelling at 100℃ for 30-60 minutes
After completely curing at 0° C. for 30 to 60 minutes or gelling and curing at 100 to 150° C. from the beginning, it is cooled to room temperature, and the jig is disassembled and stirred (11). During this curing and cooling period, the pressure in the internal resin part can be adjusted to 2 to 10K by appropriately adjusting the entrances of the injection port 5 and the degassing port 6.
g/cm2. For epoxy resin, use room-temperature curing type or heat-curing type ebogishi as the resin, and add some talc, aluminum hydroxide, quartz powder, etc. as a filler, and ceramic balloons such as glass balloons or shirasu balloons. A curing agent is added at room temperature, and the podium is degassed. The appropriate conditions for obtaining sufficient adhesion and castability were 100 parts of epoxy resin, 50 parts of filler, and 5 to 30 parts of balloon. Good results were obtained by increasing the balloon ratio even in the absence of a filler.

As explained above, the present invention has the following effects.

(1) The cylindrical magnet and the shaft are fixed by pouring resin between the two installed on a jig and applying static pressure, so the assembly work is extremely simple. Moreover, the number of man-hours and processes
It is possible to reduce the amount by 5.-45%.

(2) Since thermosetting resin is used, each part is fixed as it hardens, creating a strong adhesive force that eliminates the need for shafts.

(3) Since the assembly process is performed by simple natural injection, expensive molding machines and molds are not required, and the product has good dimensional accuracy.

(4) Weight reduction reduces inertia and improves performance.

[Brief explanation of the drawing]

FIGS. 1(a) and 1(b) are a side view and a vertical sectional view of a magnet rotor according to an embodiment of the present invention. FIG. 2 is a partial vertical sectional view of the magnet rotor during molding. 1: Circular magnet 2: Resin 3 (Fut 4: Lid Figure 7) Name of the invention Date of ministerial amendment order to correct the magnet rotor February 22, 1981 (shipment date) Target of correction

Claims (1)

[Claims] 1 In a magnet rotor using a tq cylindrical sintered permanent magnet, a shaft A7 is provided at the center inside the cylindrical sintered permanent magnet, and the shaft and the permanent magnet are heated. A magnet rotor characterized by being integrated through a curable resin. 2. The magnet rotor according to claim 1, wherein 5 to 30% of ceramic balloons such as whitebait balloons and glass balloons are contained in the thermosetting resin. 3. The magnet rotor according to claim 2, wherein a static pressure of 2 to 10 kg/cm2 is applied to the resin portion during heat curing.