| 摘要 |
<p>PURPOSE:To prevent wear of a core box by communicating the core box with a hopper, sucking and evacuating the inside of the core box, supplying green sand in the hopper into the core box by a differential pressure, forcing a rammer into the packed sand and forming a core by compression. CONSTITUTION:A core box 1 split to two parts is placed on a molding board 2 and is moved to the position of a hopper 4 by means of rollers 7, where the table 6 of a cylinder 5 is lifted to communicate a sand supplying port 8 with a discharging port 9. The inside of the box 1 is sucked and evacuated by pipes 10 through hollow chambers 11 and vent holes 12, then a gate 13 is opened to supply green sand 3 from the hopper 4 into the box 1 by the differential pressure between the hopper 4 and the box 1. The box 1 is moved to a sand compressing position together with the board 2 by means of the rollers 7 upon completion of packing of the sand 3. A rammer having a circular conical shape at the tip is forced into the sand 3 to compress the sand 3 in about 10-50% range, thereby manufacturing a green sand core. The wear of the green sand hopper and core box in the stage of molding is thus decreased and the life of the core box is extended.</p> |
