JPH06344110A - Manufacture of cast rotor - Google Patents

Abstract

PURPOSE:To obtain a cast rotor without entrapment of the air and shrinkage hole by laying a cylindrical upper die on a lower die inserted with semiprocessed product into a recessed cavity and pressurizing a half-melted billet charged into the upper die with a pressurizing punch. CONSTITUTION:The lower die 10 having the recessed cavity forming a step part narrowed downward at the bottom part and the cylindrical upper die 20 having a little shorter diameter of a hollow part 21 than the diameter of the recessed cavity are provided. The pressurizing punch 30 forms a projecting part 31 in the lower end center part. Thin sheets 43 boring a core rod hole at the central part and many small holes 42 at the intermediate position are laminated while penetrating a core rod 44 into the core rod hole, in the communicating condition of the small holes 42. The half-melted billet R is charged into the hollow part 21 in the upper die and the pressurizing punch 30 is inserted in the pressurizing condition into the hollow part 21. The half-melted billet R is spread over the small holes 42 and the closed space S, etc., and solidified and the cast rotor is taken out from the lower die 10 and the core rod 40 is pulled out. By this method, the high quality cast rotor without entraping the air is manufactured.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a cast rotor, which is a motor component, with high quality.

[0002]

2. Description of the Related Art As a conventional method for manufacturing a cast rotor, which is a motor component, a hole for a core rod is formed at the center and a large number of small holes are formed at appropriate intervals. A number of thin plates are laminated via a core rod to make a semi-finished product, this semi-finished product is set in a mold, and the small hole communication holes and the upper and lower ends of the semi-finished product are filled with molten metal by die casting to solidify. Let's take a solid and fixed method. However, in the method for producing a cast rotor as described above, since the molten metal is cast by the die casting method to make the hollow portion solid and the thin plate is fixed, entrapment and shrinkage of air, which are disadvantages of the die casting method, occur. , There was a problem that you can not get high quality products. The present invention has been made in view of the above problems, and an object of the present invention is to provide a method capable of producing a cast rotor without causing air entrapment or shrinkage.

[0003]

In order to achieve the above-mentioned problems, a method of manufacturing a cast rotor according to the present invention comprises a lower die having a concave cavity, an upper die having a cylindrical shape, and a pressure punch. On the other hand, after inserting a semi-finished product in which a number of thin plates with a small number of small holes through which a core bar penetrates in the center is stacked into the lower mold, the upper mold is placed on the lower mold and The semi-molten billet is charged into the container, and the semi-molten billet is pressed by a pressure punch to spread to the communication small holes of the semi-finished product and both upper and lower ends thereof to be solidified.

[0004]

According to the present invention, by adopting the above-described solution means, the material for fixing the thin plate to the communicating small hole portion of the semi-finished product and the upper and lower end portions thereof is a semi-molten billet. Since the material is forcibly pressed and pressed by the pressure punch to fill it, it is possible to manufacture a high-quality cast rotor without air entrapment or shrinkage.

[0005]

Embodiments of the present invention will now be described in detail with reference to the drawings. First, as equipment, as shown in FIG. 1, a lower mold 10,
The upper die 20 and the pressure punch 30 are prepared. The lower mold 10 has a concave cavity-11, and the concave cavity-
The bottom of 11 is formed in the lower tapered step 12, and a product extrusion mechanism (not shown) is additionally provided. Upper mold 2
No. 0, it is formed in a tubular shape having a hollow portion 21 having a diameter slightly shorter than the inner diameter of the concave cavity 11 of the lower mold 10. In the pressure punch 30, the protrusion 31 is formed at the center of the lower end. Are formed. Further, a semi-finished product 40 as shown in FIG. 2 is prepared for the above equipment. In the semi-finished product 40, a plurality of thin plates 43, each having a core rod hole 41 formed at the center and a plurality of small holes 42 vertically penetrating at an intermediate position at appropriate intervals, are provided for a plurality of core rods 44. The core rod hole 41 is penetrated and the small holes 42.42 are communicated with each other to be laminated.

A procedure for making the semi-finished product 40 into a product by using the equipment prepared as described above will be described. The semi-finished product 40 is inserted into the concave cavity 11 of the lower mold 10. At this time, the lower end of the core rod 44 is erected in contact with the center of the bottom surface of the concave cavity 11 so that the lower surface of the thin plate 43 at the lowermost end and the concave cavity −11.
Small hole 42.42 in communication with the lower tapered surface 11
A closed space S communicating with the upper mold is defined, and the upper surface of the uppermost thin plate 43 is at the same level as the upper surface of the lower mold 10. Next, after the cylindrical upper mold 20 is placed on the lower mold 10 and pressure-bonded thereto, a required volume of semi-molten billet R is charged into the hollow portion 21 to obtain the state of FIG.

Next, the pressure punch 30 is operated to operate the upper die 20.
Of the semi-molten billet R by pressurizing and inserting it into the hollow portion 21 of the small hole 42.42, which is in a communicating state as shown in FIG.
And the closed space S, and the space defined by the lower surface of the pressure punch 30 excluding the protrusion 31 and the upper surface of the uppermost thin plate 43, and the state is maintained until the semi-molten billet R is solidified, Manufactures a castor. Next, after the pressure punch 30 and the upper die 20 are lifted to open the upper surface of the lower die 10, the cast rotor is extruded upward from the lower die 10 through a product extruding mechanism (not shown) to manufacture the cast rotor. Take out LA. After that, the core rod 44 is extracted from the cast rotor. The above work is repeated to sequentially manufacture cast rotors.

In the above embodiment, the semi-finished product 40 has a diameter of 30 mm and a height of 30 mm in the laminated state of the thin plates 43, and the small holes 42.42 have 12 holes having a diameter of 2.4 mm. The temperature of the lower mold 10 is heated to 200 to 400 ° C.,
The press punch 30 was operated with a pressure of 250 tons to manufacture a cast rotor. As a result, the semi-molten billet R spreads sufficiently to the upper and lower spaces to form an end ring, and this end ring is in a state of being connected with the material filled in the small holes 42.42 and does not entrap air. At the same time, a solid, high quality cast rotor was produced.

[0009]

As is apparent from the above description, the present invention forcibly presses the semi-molten billet through the press punch into the semi-finished product inserted in the lower mold and pushes it into the space.
Since the caster is manufactured, it is possible to obtain a high-quality cast roller that is free from entrainment of air and is not retracted.

[Brief description of drawings]

FIG. 1 is a sectional view of a mold facility used in the present invention.

FIG. 2 is a sectional view of a semi-finished product used in the present invention.

FIG. 3 is a cross-sectional view showing a state before a pressurizing operation according to an embodiment of the present invention.

FIG. 4 is a cross-sectional view showing a pressurizing operation state showing an embodiment of the present invention.

[Explanation of symbols]

 10 Lower mold 11 Recessed cavity-12 Lower tapered step 20 Upper mold 30 Pressure punch 40 Semi-finished product 41 Core rod hole 42 Small hole 43 Thin plate 44 Core rod R Semi-molten billet S Closed space

Claims (1)

[Claims] 1. A lower mold 10 having a concave cavity-11 whose bottom is formed into a lower tapered step portion 12, and the concave cavity-1.
1. A cylindrical upper die 20 having an intermediate portion 21 having a diameter slightly shorter than the inner diameter of 1, and a protruding portion 31 at the center of the lower die and having an outer shape that can be inserted into the hollow portion 21 of the upper die 20 While the punch 30 is prepared, a large number of thin plates 43, each having a core rod hole 41 formed in the center and a plurality of small holes 42 vertically penetrating at an intermediate position at appropriate intervals, are attached to the core rod 44.
On the other hand, there is prepared a semi-finished product 40 in which the core rod hole 41 is inserted and the small holes 42 are communicated with each other.
The semi-finished product 40 is inserted into the concave cavity 11 of FIG.
After the lower surface is placed on the lower tapered step portion 12, the upper die 20 is placed on the lower die 10 and a semi-molten billet R is put into the upper die 20 to press the pressure punch 30. Upper mold 20
Of the hollow cavity 21 of the concave cavity 1 through a large number of small holes 42 through which the semi-molten billet R is communicated.
2. A method for manufacturing a cast rotor, characterized in that it is spread over a hollow portion defined by the lower surface of the pressure punch 30, the upper surface of the thin plate 43 and the upper die 20 to solidify.