JPS6327944B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of manufacturing a permanent magnet rotor whose starting winding is formed by die casting.

When manufacturing the starting winding for a permanent magnet motor with a starting winding, a copper rod is used for the starting winding, a copper plate is used for the end ring, and two methods are used: welding and die casting. There is a method, but
In either case, the entire rotor becomes hot.

Generally, when permanent magnets are exposed to high heat, they tend to crack and crack, and their properties deteriorate. An object of the present invention is to efficiently manufacture a self-starting permanent magnet motor without impairing its magnetic properties and mechanical strength, paying attention to the above-mentioned viewpoints.

In this manufacturing method, first, an iron core is constructed which has a plurality of permanent magnet storage grooves opened on the outer circumferential surface and has a starting winding storage groove between adjacent permanent magnet storage grooves.

Then, a contact plate is applied to both ends of the iron core, in which both ends of the permanent magnet storage groove are closed, and the portion opposite to the starting winding storage groove is open.

Die casting is performed in this state, and the starting winding is formed from the molten metal. Insert an object with the same shape as the magnet into the permanent magnet storage groove.

After that, the permanent magnet is pasted and fixed in the permanent magnet storage groove with adhesive.

Examples of the method of the present invention will be described below with reference to the drawings.

A rotor core 4 is constructed by laminating iron plates 3 having a permanent magnet housing groove 1 and a starting winding housing groove 2. Both ends of the permanent magnet housing groove 1 are closed, and a contact plate 6 having an opening 5 through which molten metal passes is applied to both sides of the rotor core 4 in a portion facing the starting winding housing groove 2. Next, the permanent magnet storage groove 1 of the rotor core 4
An object having the same shape as the permanent magnet 10 is inserted into the rotor core 4 and the back plate 6 are tied together by inserting a core metal into the shaft hole 12 previously drilled in the center of the rotor core 4 and the center of the back plate 6. Next, as shown in FIG. 2, the bundled rotor core 4 and contact plate 6 are assembled into a casting jig 7 that abuts the cylindrical surface of the rotor and covers the end surface. die casting. That is, the molten metal enters from the sprue 8, forms the sprue-side end ring 9a with the sprue-side end ring mold 7a, then passes through the opening 5 of the contact plate 6, and then the starting winding storage groove 2 to the opposite side of the sprue. reach. Therefore, the opposite end ring 9b is formed by the opposite end ring mold 7b. The backing plate 6 has the role of securing a space in the permanent magnet housing groove 1 by keeping molten metal from entering it, and having the role of allowing molten metal to flow into the starting winding housing groove 2. A pair of end rings 9a and 9b are made of die-cast molten metal, and the starting winding conductor 9c provided in the starting winding storage groove 2 is short-circuited at both ends through the opening 5 of each backing plate 6. On the other hand, it has the role of fixing the rotor core 4 and the contact plate 6. The rotor core 4 and the contact plate 6, which constitute the starting winding conductor 9c and the end rings 9a and 9b, are taken out from the casting jig 7 and placed in the permanent magnet storage groove 1 of the rotor core 4 in advance. Permanent magnet 1
0, and then insert the permanent magnet 1 into the permanent magnet storage groove 1 of the rotor core 4 with adhesive.
Glue and fix 0. Note that the mandrel 11 that binds the rotor core 4 and the contact plate 6 may be removed after the die-casting process. As described above, in the present invention, a die-casting operation is performed after inserting an object of the same shape as a permanent magnet into a permanent magnet storage groove, and after the die-casting operation, the same-shaped object is removed and the permanent magnet storage groove is inserted into a permanent magnet storage groove. A permanent magnet is attached and fixed inside with adhesive. Therefore, according to the present invention, since the die-casting operation is performed after the rotor core is assembled into a circular shape, the shape of the casting jig for this die-casting operation and the opening operation of the jig are simplified. , production equipment can be obtained at low cost, and the productivity of die-casting work is also improved, and conventional production equipment for aluminum die-casting rotors can be used as is. At the same time, since the permanent magnets are attached after the die-casting operation, the permanent magnets are not affected by the heat during the die-casting operation, so the following effects can be obtained compared to conventional permanent magnet rotors.

(a) Deterioration of the magnetic properties of permanent magnets can be prevented.

(b) Physical deterioration of permanent magnets, that is, cracks and cracks in permanent magnets, can be prevented.

(c) It is possible to prevent a decrease in the bonding strength of permanent magnets due to melting or deterioration of the adhesive used to bond permanent magnets.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing an example of a rotor manufactured by the present manufacturing method, taken at the center along a line perpendicular to the axis. FIG. 2 is a sectional view parallel to the axis and through the starting winding groove, and a view showing the casting jig. FIG. 3 is a front view showing the shape of the contact plate. DESCRIPTION OF SYMBOLS 1... Permanent magnet storage groove, 2... Starting winding storage groove, 3... Iron core, 4... Rotor core, 5... Opening, 6...
Plate, 7... Casting jig, 9a, 9b... Pair of end rings, 9c... Starting winding conductor, 10... Permanent magnet,
11... Core metal, 12... Shaft hole.

Claims (1)

[Scope of Claims] 1. An iron plate having a plurality of permanent magnet storage grooves opened on the outer peripheral surface, a starting winding storage groove between adjacent permanent magnet storage grooves, and a shaft hole in the center. A rotor core is prepared in which a large number of layers are laminated, and a permanent magnet housing groove in the rotor core is provided at both ends, with both ends of the permanent magnet housing groove being closed, and a portion facing the starting winding housing groove being closed. A contact plate having an opening and a shaft hole in the center is applied, and an object having the same shape as the permanent magnet is inserted into the permanent magnet storage groove of the rotor core, and the shaft hole of the rotor core and the shaft of the contact plate are inserted. A mandrel is passed through the hole to bind the rotor core and the contact plate, and the bundled rotor core and contact plate are assembled into a casting jig that abuts the cylindrical surface and covers the end face of the rotor core and the contact plate. A pair of injecting molten metal from the opening side of the plate to form a starting winding conductor in the starting winding storage groove of the rotor core, and connecting with the starting winding conductor through the opening of each of the plates. The starting winding conductor and the bundled rotor core and contact plate, which constitute the end ring, are taken out from the casting jig and placed in the permanent magnet storage groove of the rotor core in advance. A permanent magnet rotor having a starting winding, characterized in that an object having the same shape as the permanent magnet is removed, and then the permanent magnet is fixed by gluing the permanent magnet into the permanent magnet storage groove of the rotor core with an adhesive. manufacturing method.