Die cast casting apparatus and method for releasing casting from mold

Abstract

A die casting apparatus includes: a fixed mold and a movable mold for forming a casting, wherein an insert core is disposed slidably in a movable main mold of the movable mold to form a protruding portion of the casting. The movable mold includes: a casting ejecting part for releasing the casting from the main mold, a core moving part for moving the core in a casting demolding direction, and a protruding-portion demolding part for releasing the protruding portion from the core. In a first demolding step, a control part controls the casting ejecting part, core moving part, and protruding-portion demolding part to release the casting from the main mold by the casting ejecting part and move the core together with the casting by the core moving part. In a second demolding step, the protruding portion is released from the core by the protruding-portion demolding part.

1 . A die casting apparatus including a fixed die and a movable die to form a cavity for molding a casting, in which an insert core is slidably provided in a movable main die of the movable die to form a protruding portion of the casting,
 wherein the movable die includes: product ejecting means to release the casting from the movable main die; core moving means to move the core in a demolding direction of the casting; and protruding-portion demolding means placed on both sides of the insert core formed of a plurality of straight extending standing plates arranged side by side, the both sides being located in a straight extending direction of the straight extending standing plates, to release the protruding portion from the core,   wherein control means to control operations of the product ejecting means, the core moving means, and the protruding-portion demolding means is configured to execute a first demolding step in which the product ejecting means releases the casting from the movable main die and the core moving means moves the core in association with the casting, and a second demolding step in which the protruding-portion demolding means alternately pushes each of the both sides in the straight extending direction of the standing plates forming the insert core to release the protruding portion from the core.   
     
     
         2 . The die casting apparatus according to  claim 1 , wherein the protruding-portion demolding means is configured to perform the second demolding step by pushing the casting near the protruding portion in the demolding direction. 
     
     
         3 . (canceled) 
     
     
         4 . The die casting apparatus according to  claim 1 , wherein the core moving means and the protruding-portion demolding means are integrally formed by a hydraulic unit configured to separately independently extend and contract operation rods connected to the core and ejector pins to be pressed against a portion of the casting near the protruding portion. 
     
     
         5 . The die casting apparatus according to  claim 1 , wherein the core moving means and the protruding-portion demolding means are integrally formed by a hydraulic unit configured to separately independently extend and contract operation rods connected to the core and plate-shaped ejector blocks to be pressed against the casting near the protruding portion. 
     
     
         6 . The die casting apparatus according to  claim 4 , wherein the product ejecting means includes a plurality of ejector pins or ejector blocks fixed to an ejector plate to be moved by a hydraulic cylinder, and the control means is hydraulic control means to drive and control the hydraulic unit and the hydraulic cylinder. 
     
     
         7 . A die casting apparatus including a fixed die and a movable die to form a cavity for molding a casting, in which an insert core is slidably provided in a movable main die of the movable die to form a protruding portion of the casting,
 the movable die includes: product ejecting means to release the casting from the movable main die; core moving means to move the core formed of a plurality of separate blocks so that each of the separate blocks of the core is moved in the demolding direction of the casting to release the protruding portion from the insert die; and protruding-portion demolding means to push the casting at a portion near the protruding portion in the demolding direction, and   wherein control means to control operations of the product ejecting means, the core moving means, and the protruding-portion demolding means is configured to execute a first demolding step in which the product ejecting means releases the casting from the movable main die and the core moving means moves the core in association with the casting, and a second demolding step in which the separate blocks are stepwise moved relatively in an opposite direction to the demolding direction by the core moving means with respect to the protruding portion of the casting pushed or supported by the protruding-portion demolding means to release the protruding portion from the core.   
     
     
         8 . The die casting apparatus according to  claim 7 , wherein when the core is configured to form the protruding portion consisting of a plurality of straight extending standing plates arranged side by side, the separate blocks are separated in a straight extending direction of the standing plates. 
     
     
         9 . The die casting apparatus according to  claim 7 , wherein the core moving means and the protruding-portion demolding means are integrally formed by a hydraulic unit configured to separately independently extend and contract operation rods connected to the separate blocks of the core and ejector pins to be pressed against the casing near the protruding portion. 
     
     
         10 . The die casting apparatus according to  claim 7 , wherein the core moving means and the protruding-portion demolding means are integrally formed by a hydraulic unit configured to separately independently extend and contract operation rods connected to the separate blocks of the core and plate-shaped ejector blocks to be pressed against the casing near the protruding portion. 
     
     
         11 . The die casting apparatus according to  claim 9 , wherein the product ejecting means includes a plurality of ejector pins or ejector blocks fixed to an ejector plate to be moved by a hydraulic cylinder, and the control means is hydraulic control means to drive and control the hydraulic unit and the hydraulic cylinder. 
     
     
         12 . (canceled) 
     
     
         13 . (canceled) 
     
     
         14 . (canceled) 
     
     
         15 . A method for releasing a casting from a die, using a die casting apparatus to form the casting including a protruding portion, the method including separating a movable die from a fixed die for die opening and then demolding the casting from the movable die, wherein the method includes: a first demolding step including moving an insert core configured to form the protruding portion in association with the casting to release a portion of the casting other than the protruding portion from a movable main die of the movable die; and a second demolding step including releasing the protruding portion from the core,
 wherein when the core is configured to form the protruding portion consisting of a plurality of straight extending standing plates arranged side by side,   the second demolding step uses protruding-portion demolding means placed on both sides of the core corresponding to both side positions of the standing plates in a straight extending direction and includes alternately operating each side of the protruding-portion demolding means to push the casting in the demolding direction.   
     
     
         16 . A method for releasing a casting from a die, using a die casting apparatus to form the casting including a protruding portion, the method including separating a movable die from a fixed die for die opening and then demolding the casting from the movable die, wherein the method includes: a first demolding step including moving an insert core configured to form the protruding portion in association with the casting to release a portion of the casting other than the protruding portion from a movable main die of the movable die; and a second demolding step including releasing the protruding portion from the core,
 wherein the second demolding step uses the core formed of a plurality of separate blocks and includes stepwise moving the separate blocks to release the protruding portion by each separate block.   
     
     
         17 . (canceled) 
     
     
         18 . (canceled)