Abstract: A melting casting process produces meltable metal cores for subsequent molding of components made of plastic material and encapsulated components such as turbine blades so they may be held for machining. The process utilizes a double acting piston in a cylinder to permit unlimited dispensing capacity without having to pause between piston strokes. The apparatus comprises a tank for containing molten metal, a double acting cylinder having both ends closed and an injection piston therein and an operating mechanism for reciprocating the piston in the cylinder. Valve mechanisms are provided so that when the piston is moved in either direction in the cylinder, a flow of molten metal passes through an injection passageway into a die, and molten metal from the tank fills the space behind the moving piston thus the cylinder always remains full of molten metal.

Abstract: A multiple metallic core assembly for use in production of a plastic injection-molded component is formed by injecting molten metal alloy into a core die at a fill stage of an indexing system, indexing the core die through a cooling stage to an unloading stage, and removing the core from the core die and inserting the core in one of a plurality of locations of the core assembly. Individual cores are continued to be formed as discussed above until all the locations of the core assembly are filled, and the core assembly is complete. Therefore, the core assembly is removed and transported to a plastic molding machine to produce the plastic component. Then, the core assembly is melted out from the plastic component in hot oil, and the molten metal alloy produced thereby is returned to a molten metal alloy tank.

Abstract: In the casting of metal alloys with low melting temperatures, an improved control system for lowering an injection piston in an injection cylinder is provided to avoid porosity occurring in castings. There is a fluid operated drive cylinder with a drive piston connected to the injection piston. A transducer is linked to the injection piston to provide an indication of location, and a controller compares the position of the injection piston with a predetermined time/distance profile and produces an injection stroke signal which is used to control the drive cylinder and ensure the injection piston follows the time/distance profile.

Abstract: In the casting of metal alloys with low melting temperatures, there is provided a nozzle for an interface connection between a transfer line and a die which permits misalignment and a variable height differential. Meal alloys with low melting temperatures are made for cores in subsequently molded plastic components and for encapsulating components for machining the other finishing steps. The nozzle has a base with a valve therein, a nozzle body adapted to move relative to the base to open the valve, and a spring to hold the valve closed. A sleeve joins the nozzle body and the base, and a connector on the nozzle body provides an interface connection between the transfer line and the die so that when the connector interfaces with the die, the valve is open.

Abstract: A metal casting process for producing melt-out metal cores and the like made of metal alloys with low melting temperatures achieves a casting with uniform density, high quality finish and a fine grain structure. The process and apparatus do not require the pre-pressurization of a charging cylinder and permit closed dies to be used. The apparatus comprises a molten metal alloy tank, a cylinder in the tank having at its base a connection to a passageway leading through the tank to a die located outside the tank. A valve is provided in the passageway, located in the tank having a first position where the passageway to the die is open and a second position where the passageway to the die is closed. In the second position, a valve port provides a connection from the cylinder to the molten metal alloy in the tank.

Abstract: A metal casting process for producing melt-out metal cores and the like made of metal alloys with low melting temperatures achieves a casting with uniform density, high quality finish and a fine grain structure. The process and apparatus do not require the pre-pressurization of a charging cylinder and permit closed dies to be used. The apparatus comprises a molten metal alloy tank, a cylinder in the tank having at its base a connection to a passageway leading through the tank to a die located outside the tank. A valve is provided in the passageway, located in the tank having a first position where the passageway to the die is open and a second position where the passageway to the die is closed. In the second position, a valve port provides a connection from the cylinder to the molten metal alloy in the tank.

Abstract: An improved valve mechanism for casting metal alloys with low melting temperatures provides two valves in a single assembly inside an alloy tank. The valves being in the tank reduces the formation of oxides which can occur in air and tends to reduce leaks. The apparatus comprises a tank adapted to contain molten metal alloys, a cylinder in the tank having at its base a connection to an injection passageway which leads through the tank to a die located outside the tank. A piston reciprocates in the tank which allows molten metal alloy to be drawn into the cylinder and forced through the passageway to the die. A control system for the piston controls accurately the speed of the piston in the cylinder when the molten metal alloy is fed to the die.

Abstract: A metal casting process for producing melt-out metal cores and the like made of metal alloys with low melting temperatures achieves a casting with uniform density, high quality finish and a fine grain structure. The process and apparatus do not require the pre-pressurization of a charging cylinder and permit closed dies to be used. The apparatus comprises a molten metal alloy tank, a cylinder in the tank having at its base a connection to a passageway leading through the tank to a die located outside the tank. A valve is provided in the passageway, located in the tank having a first position where the passageway to the die is open and a second position where the passageway to the die is closed. In the second position, a valve port provides a connection from the cylinder to the molten metal alloy in the tank.

Abstract: A casting is made from a low melting point alloy having a solidus temperature in the range of 35.degree.-300.degree. C. by subjecting a charge of molten alloy to pre-pressurization then delivering the charge at a flow rate of 0.1 to 1 kg/sec into a die and maintaining the metal in the die under pressure for a time in excess of that required to fill the die.