JPS6213239A - Casting method by changing flow of molten metal - Google Patents

Abstract

PURPOSE:To prevent the generation of a rough surface and shrinkage cavity by attaching a cap consisting of the same material as the material of a molten metal to a core near an inlet of a cavity facing the gate part in a metallic mold and pouring the molten metal into the mold. CONSTITUTION:The cap 3 consisting of the same material as the material of the molten metal is attached to the position of the core 4 forming the cavity 5 which faces the end part 6 of the gate part 1 of the metallic mold 2 by pushing the attaching part 3b thereof into the core part. Therefore the molten metal poured into the mold 2 passes the gate part 1 and contacts with the gate 3 to flow toward an arrow P direction without contacting with the core 3 and without blowing up into the cavity 5. The cap 3 is melted away at the point of the time when the pouring of the molten metal into the cavity 5 is completed. The substantial feeding pressure is exerted into the cavity 5. The generation of the rough surface and shrinkage cavity to the position corresponding to the gate part 1 of the casting product is thus obviated.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a casting method for changing the flow of molten metal in a cavity facing a weir in a mold.

(Prior Art) Conventionally, in the field of casting, a weir is provided in a cavity within a mold. At this dam, the inflow pressure of the molten metal increases rapidly and turbulence occurs in the molten metal flow, resulting in rough skin in the area of the product that corresponds to the dam, and the constant movement of the molten metal causes a delay in solidification. There is a disadvantage that directional solidification is disrupted and internal defects (cavities) are likely to occur on the product side.

(Problems to be Solved by the Invention) The object of the present invention is to provide a casting method that does not cause rough skin or cracks in the product.

(Means for Solving the Problems) In order to solve the above-mentioned problems, the present invention provides a method for pouring molten metal by attaching a lid made of the same material as the molten metal to the core near the entrance of the cavity facing the weir in the mold. It has become.

(Function of the invention) When the molten metal is cast by the above method, when it flows into the cavity, it does not directly hit the core for forming the groove, but flows quietly in the lateral direction, so that the inflow pressure of the molten metal at the weir increases rapidly. turbulence does not occur in the molten metal flow. Furthermore, there is no delay in solidification due to movement of the molten metal, and no collapse of directional solidification occurs.

(Description of Embodiments) Casting of an aluminum cylinder head will be described below as an embodiment of the present invention based on the drawings. Figure 1.2 shows a first embodiment. FIG. 1 shows a case in which molten metal is poured from the bottom side of the cylinder head. In the figure, N3 made of the same material as the molten metal (aluminum in this embodiment) is attached to the part of the core 4 forming the cavity 5 facing the end 6 of the weir part 1 of the mold 2.
It is attached by pushing b. At this time, the main body 3a of the lid s43 is plate-shaped and in close contact with the core 4. Further, as shown in FIG. 2, the contour of the main body portion 3a is set larger than the contour of the end portion 6 of the weir portion 1. Therefore, the molten metal poured into the mold 2 passes through the weir 1, hits the lid 3, and flows in the direction of arrow P, so it does not hit the core 4 and does not blow up into the cavity 5.

When the filling of the molten metal into the cavity 5 is completed, the N3 has melted and disappeared, and sufficient pressure is applied to the inside of the cavity 5. As a result, weir part 1 of the cast product
There will be no rough skin or hives in the affected areas.

Figure 3.4 shows the case of pouring metal from the side of the cylinder head. In the figure, a hook-shaped lid 13 made of the same material (aluminum) as the molten metal is attached to a hook portion 1 of the core 14 forming the cavity 15 facing the end 16 of the weir portion 11 of the mold 12.
3b. Body part 13 of lid 13
The outline of a is set larger than the outline of the end 16 of the weir part 11, as shown in FIG. Therefore, the molten metal flows quietly in the space below the main body 13a of the lid 13 and the end 16 of the weir 11, and reliably flows from the bottom of the cavity 15 into the cavity 15.
Fill it up. As in the first embodiment, when the filling is completed, the lid 13 is melted, and sufficient uplift pressure is applied to the cavity 15 from the dam 11. As a result, no rough skin or cracks occur in the part corresponding to the dam part 11 of the cast product.

(Effects of the Invention) This invention performs casting by changing the flow of the molten metal using the above method, so the molten metal flows quietly and reliably in the cavity facing the weir without causing turbulence or sudden pressure changes. Since the lid is molten when the filling is completed, no rough skin or cracks will occur in the part of the cast product that corresponds to the dam. Furthermore, since the lid is made of the same material as the cast product, there is no need to change the composition of the return material.

[Brief explanation of the drawing]

FIG. 1 shows a front view of 17111I7i of the first embodiment. Figure 2 shows the Q determination of Figure 1. FIG. 3 shows a longitudinal sectional front view of the second embodiment. FIG. 4 shows a sectional view taken along the line A--A in FIG. 3. 1.11... Weir part 2.12... Mold 3.13... Lid 4.14... Core 5.15... Cavity

Claims (1)

[Claims] A casting method that changes the flow of molten metal and is characterized by attaching a lid made of the same material as the molten metal to the core near the entrance of the cavity facing the weir in the mold and pouring the molten metal.