Centrifugal casting machine with venturi actuated vacuum venting
A device affixed to a centrifugal force casting machine that developes a vacuum as it travels through the air on the spinning arm of the casting machine. The developed vacuum is used to evacuate unwanted gasses from a casting mold.This invention relates to a machine for centrifugally casting tubular sleeves. In practice the machine which we have devised is used in casting cylindrical sleeves for use in internal combustion engines, in which the quality of the cast metal must be very high, being of an especially uniform This Invention has been devised to provide a machine for casting, with the application of centrifugal force, the shells of bombs and other projectiles and articles of a like shape or of any cylindrical or other shapes capable of being moulded about a common axis. A portable, centrifugal casting machine has a drive motor and shaft that rotates a generally T-shaped rotor, the head of which is inclined relative to the stem with the trailing end of the head radially outward of the leading end thereof. 
A mold supporting cradle is mounted on the trailing end portion of the rotor head and a crucible, with a metal discharging outlet in the end thereof toward the cradle, is mounted for limited sliding movement along a path lengthwise of the head of the T-shaped rotor. A counterweight is mounted on the opposite end of the stem of the rotor from its head.
When the motor is energized, the starting torque of the rotor drives a charge of molten metal in the crucible, by a combination of acceleration, inertia and centrifugal force, through the crucible outlet and into a mold cavity in a mold mounted on the cradle, where the metal is retained under centrifugal pressure until its sets.
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