Centrifugal casting machine for manufacturing rotor
Disclosed herein is a centrifugal casting machine, including: a rotating plate rotating by means of a motor; a cylindrical sleeve installed on the rotating plate and having an internal diameter corresponding to an external diameter of silicon steel plates constituting a core in the sleeve; an upper mold internally installed on the sleeve to define a first molding space into which a molten metal is introduced to mold an end ring; a lower mold internally installed on the sleeve to define a second molding space into which a molten metal is introduced to mold an end ring; a dummy shaft fitted in the center of the core and coupled to the lower mold; a cap coupled to an upper end of the dummy shaft to press the core; and a hydraulic ram coupled to the lower mold to move the lower mold up and down and coupled to the rotating plate to rotate therewith.
1. A centrifugal casting machine, comprising:
a rotating plate having a through-hole formed in a central portion thereof and configured to rotate by means of a rotational force;
a sleeve installed on the rotating plate and having a hollow cylindrical shape, wherein an internal diameter of the sleeve corresponds to an external diameter of a core stacked inside the sleeve;
an upper mold disposed inside the sleeve such that an outer circumferential surface of the upper mold is in contact with an inner circumferential surface of the sleeve, the upper mold defining a first molding space between the upper mold and the core, to mold an upper end ring;
a lower mold disposed inside the sleeve and slidingly moving along the inner circumferential surface of the sleeve, the lower mold defining a second molding space between the lower mold and the core to mold a lower end ring;
a dummy shaft coupled to a top side of the lower mold to support the core and prevent a molten metal from being introduced into a center of the core;
a cap coupled to a top end of the dummy shaft to press the core from a top; and
a hydraulic ram slidingly inserted into the through-hole of the rotating plate, a top end of the hydraulic ram being coupled to a bottom side of the lower mold and a bottom end of the hydraulic ram being coupled to a lifting device such that the hydraulic ram moves up and down by the lifting device, thereby the lower mold moving up and down relatively to the rotating plate.
2. The centrifugal casting machine according to claim 1 , wherein the hydraulic ram includes at least one coupling protrusion formed on an outer surface thereof and extending along a longitudinal direction of the hydraulic ram, and the through-hole of the rotating plate includes at least one groove with which the longitudinal protrusion engages.
3. The centrifugal casting machine according to claim 1 , wherein the sleeve has a seating step formed inside an upper portion of the sleeve, on which the upper mold is seated, the seating step having a diameter greater than the internal diameter of the sleeve, and the sleeve has at least one key hole formed in the seating step to fix the upper mold to the sleeve by a key.
4. The centrifugal casting machine according to claim 1 , wherein the lower mold includes
a first coupling hole formed in a center portion of the bottom side thereof, to which the top end of the hydraulic ram is engaged, and
a second coupling hole formed in a center portion of the top side thereof, to which the bottom end of the dummy shaft is engaged.
5. The centrifugal casting machine according to claim 1 , wherein the sleeve further includes a flange outwardly protruding from a bottom end thereof to install the sleeve to the rotating plate by means of bolts.