Patent ID: 8082973

Claim:
A method for pulling and inserting a core ( 3 ) with concave slots in synchronization with the opening and closing of a mold in a cavity including a fixing half ( 1 ) and a moving half ( 2 ), or a cavity including a fixing half ( 1 ), a moving half ( 2 ) and several cavity plates installed between the fixing half ( 1 ) and moving half ( 2 ) as well as the core ( 3 ) moving reciprocally inside the cavity, including: step (1): prior to mold opening, a stroke is preset as a displacement of a hook ( 11 ) in disengaging from the hook lock ( 12 ) affixed to the fixing half ( 1 ) for unlocking core lock pieces ( 13 ) from the concave slots of the core ( 3 ); step (2): synchronous mold opening and core pulling, the moving half ( 2 ) unlocks the core lock pieces ( 13 ) from the concave slots of the core ( 3 ) fixed with a gear spindle ( 5 ) of a gear train, and moves in the stroke preset in step 1) until a limit of a gear rack ( 9 ) or a gear chain ( 10 ) disposed over the hook ( 11 ) is reached, while, synchronously, a downward movement of a transmission gear ( 8 ), engaged with the gear rack ( 9 ) of the gear chain ( 10 ), drives a gear of a transmission train to move the gear spindle ( 5 ), which pulls out the core ( 13 ) in two guide press pieces ( 4 ) disposed on a side of the moving half ( 2 ) via a core pulling and insertion gear ( 6 ) of the gear spindle ( 5 ), or via a transmission rack ( 7 ) affixed directly with the core ( 3 ); step (3): completing mold opening: the moving half ( 2 ) continues to travel until a mold push rod is activated; step (4): synchronous mold closing and core insertion: the moving half ( 2 ) drives the hook ( 11 ) to travel reversely to drive the core ( 3 ) for an insertion into the cavity until reaching either the limit of the gear rack ( 9 ) or the gear chain ( 10 ) and unlocking the hook lock ( 12 ), the transmission gear ( 8 ) moves upwards; and the core lock pieces ( 13 ) travel in the stroke preset in step (1) and then locks the core ( 3 ) with core lock pieces ( 13 ) engaging concave slots of the core ( 3 ) to prepare for mold opening after casting, step (5) repeat the steps (1)-(4).