JPH02211042A - Manufacturing of rotor of motor - Google Patents

Abstract

PURPOSE:To obtain a rotor with high quality and low noises by using a metallic pipe-like component to remove voids in case of die casting, preventing flashing, and separately providing a void necessary for taking out a laminated core after die casting. CONSTITUTION:Die casting conductors 2 are formed in a groove made in a laminated core 1. End ring forming metal molds 4 and 5 are used for the die casting. The laminated core 1 is supported by an intermediate mold 3 through a pin 6 from the side of an internal diameter and a pipe-like component 8 from the side of an external diameter. The pipe-like component 8 is such a metallic component that it is fitted to the laminated core 1 without making almost no-gap and has thermal expansion characteristic, and there is a void 9 between the metallic component and the internal circumference of the intermediate mold 3. There is no void between the laminated core 1 and the pipe-like component 8, so that no flash occurs in the conductors 2. There is the void 9, so that the laminated core 1 and the pipe-like component 8 are taken out from a die casting metal mold, and they can be separated by an another production process to protect productivity.

Description

[Detailed description of the invention] Industrial applications The present invention relates to a method of manufacturing an induction motor rotor.

Conventional technology In the conventional rotor manufacturing method, the laminated core is engraved between the outer periphery of the laminated core and the outer periphery of the laminated core due to the heat and pressure during die casting, which prevents the laminated core from coming out of the mold. For example, if the groove formed in the laminated core in which the die-cast conductor is located is an open groove, there is a high possibility that flash will occur on the outer periphery of the core during die-casting.

This will be explained below with reference to the drawings.

FIG. 2 is a sectional view showing a conventional rotor die-casting mold. 1 is a laminated core, 2 is a die-cast conductor die-cast in a groove formed in the laminated core 1, and 3 is an intermediate mold for holding the laminated core 1, which is composed of a base portion 3a and a replacement portion 3b. 4 is an end ring forming mold (movable type), and 5 is an end ring forming mold (fixed type, sprue side). 6 is a bottle that supports the laminated core 1 from its inner diameter. 7 is a gap between the laminated iron core l and the intermediate mold 3.

Problems to be Solved by the Invention In the conventional example shown in FIG. 2, the gap 7 is caused by the fact that the outer diameter of the laminated core 1 is engraved due to the heat and pressure during die casting, so that the laminated core 1 is removed from the intermediate mold 3 after die casting. This is provided in advance to prevent it from falling out. In general, from the viewpoint of productivity, this gap 7 is set so that it remains a gap even when the laminated core 1 after die-casting is engraved.

For this reason, for example, if the laminated core 1 has an open groove, the die-cast conductor 2 may leak into the gap 7 during die-casting, and when the laminated core 1 is taken out, there is a possibility that it will become cast burr and adhere to the outer periphery of the laminated core 1. is large. This cast burr falls off during operation of the electric motor and not only has an adverse effect on the rotating system, but also may increase the noise of the electric motor.

The present invention prevents the occurrence of casting burrs and provides a high-quality, low-noise electric motor.

Means for Solving the Problems In order to solve the problems, in the present invention, the outer periphery of the laminated core inserted into the mold fits with the inner periphery of the mold, and the inner periphery has a substantially clearance fit with the outer periphery of the laminated core. Metal tubular parts that fit together at O are attached to the laminated core in advance, and this is inserted into a mold and die-cast.

Operation In the present invention, in order to prevent the above-mentioned cast burr generation, a metal tubular part is used to eliminate the void around the outer periphery of the laminated core during die-casting, and to provide a separate void for removing the laminated core after die-casting. As a result, the rotor manufacturing method for providing high-quality, low-noise electric motors will be improved.

Example An embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a sectional view showing a die casting mold according to an embodiment of the present invention. 1 to 6 are the same as the conventional example (FIG. 2). 8 is a heat-engraved metal tubular part that fits into the laminated iron core 1 with a gap of approximately O, and is separated from the outer periphery of the intermediate mold 3 by an empty Fi9.
through. At this time, since there is no gap between the outer periphery of the laminated core 1 and the tubular component 8, burrs of the conductor 2 are not generated on the outer periphery of the laminated core after die-casting. The effect is particularly great when the laminated core has open grooves.

After die-casting, since the void 9 exists, the laminated core 1 and the tubular part 8 can be taken out from the die-casting mold, and the core and tube can be removed in a separate process, so productivity will not be adversely affected.

As can be seen from the effects of the invention, it is possible to produce high-quality rotor rotors without casting burrs. Especially in recent years, rotor grooves are often made open in order to reduce noise in electric motors. The rotor manufacturing method can be significantly improved, and a high-quality, low-noise electric motor with high productivity can be provided.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a die-casting mold according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view of a conventional die-casting mold. 1... Laminated iron core, 2... Die-cast conductor, 3... Intermediate mold, 4... End ring forming mold (movable), 5... ... End ring forming mold (fixed), 8... Tubular parts.

Claims (1)

[Claims] In a die-casting machine consisting of two molds that form the end rings at both ends of the cage-shaped rotor of an induction motor and a mold that holds the circumference of the laminated core, the laminated core inserted into the die-casting machine has a A rotating electric motor characterized in that a tubular part is fitted on the outer periphery with a clearance between the mold and the inner periphery is fitted with the outer periphery of the laminated core with almost zero clearance, and this is inserted into the mold and die-cast. Method of producing children.