Casting method, upper mold assembly, and method for fixing core to the upper mold

Abstract

This invention provides a casting method characterized by comprising the step of fixing a core to an upper mold to provide an upper mold assembly, the step of pouring a minimized amount of molten metal necessary for providing a cast product into a concave in a lower mold, the step of moving the upper mold assembly at a predetermined first speed and lowering the upper mold assembly to a predetermined height just above the surface of the molten metal in the concave, the step of varying the lowering speed of the upper mold assembly from the first speed to the predetermined second speed to further lowering the upper mold assembly from the predetermined height, the step of detecting information about the state of the upper mold assembly in such a state that the upper mold assembly has been superimposed on or lowered toward the lower mold, and the step of stopping of the lowering of the upper mold assembly after the detection that the state information has reached predetermined state information. The core is fixed to the upper mold depending upon a frictional fitting relationship between mechanical means, an adhesive, and a core-side fitting protrusion and the concave fitting part, or the engagement relationship between a core-side engaging projection and molding sand to be tamped down.

Description

technical field [0001] The present invention relates to a method of manufacturing castings (ie, a casting method), an upper mold assembly used in the method, and a method of fixing a core relative to the upper mold. More specifically, it relates to a casting method for obtaining a casting by using a sand pressure casting process, that is, pouring the minimum amount of molten metal required to obtain the casting into a lower mold and fitting the upper mold to the lower mold. Background technique [0002] In metal casting using a sand mold, an upper mold is joined to a lower mold to form a mold cavity, and molten metal (slurry) is poured into the cavity to produce a casting. In this widely used casting method, it is necessary and indispensable to provide a flow path of the pouring metal called a casting plan, which is not related to the shape of the product. The purpose is to control the flow of the pouring metal and prevent it The mixing of pure substances and gases prevents...

AI Technical Summary

Problems solved by technology

However, according to the sand pressure casting process, the upper mold is covered after pouring the lower mold. Therefore, if the core is pre-set on the lower mold before pouring, the core will be damaged due to The buoyancy of the magma floats up, which leads to the problem of shape defects in the finished product

Therefore, only in the sand pressure casting process, if the core is placed in the lower mold as in the past, there will be a problem that the core will float during the pouring process, so it is also necessary to prevent the core in the mold from floating.

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