MECHANISM FOR BLOWING SAND IN BLOWING TYPE MOLDING DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a sand blowing mechanism, in which the compressed air blown therein has reduced resistance at the time of passing an inner cylinder and the inner cylinder is easily manufactured and further, the packing of the molding sand into a pattern box is executed independently of the molding sand quantity in the inner cylinder. ;SOLUTION: The inner cylinder 7 is fitted to the inner part of an outer cylinder 2 extended in the vertical direction to form an annular space 8, and the space 8 has an air exhaust introducing chamber 11 at the upper part and an air supply introducing chamber 12 at the lower demarcated with a partition member 9. A vent hole communicated with the air exhaust introducing chamber 11 is formed at the upper part of the inner cylinder 7 and an air exhaust hole 15 communicated with the air exhaust introducing chamber 11 is arranged in the outer cylinder 2. An air supplying hole 18 communicated with the air supply introducing chamber 12 is provided in the outer cylinder 2 and plural pieces of nozzles enabling the ejection of the compressed air into the air supply introducing chamber 12 toward the circumferential direction of inner surface of the inner cylinder 7 are arranged at the lower part of the inner cylinder 7.;COPYRIGHT: (C)1998,JPO