PRODUCTION OF SOUND INSULATING MATERIAL

摘要

PROBLEM TO BE SOLVED: To make producible an excellent sound insulating material uniform in material density over all by reducing the blowing air volume correspondingly to the increase of the blowing resistance as the treated material is packed when the treated material is blown and packed into a forming die. SOLUTION: A preform forming die 20 having a shape of die surface simpler than that of the normal forming and a normal forming die 21 having a die surface corresponding to a shape of an actual sound insulating material are installed sequentially along the line direction at the forming site 17. A blowing resistance sensor of a wind pressure sensing type is installed at the adequate position of the die 20. The blowing air volume from a blower 12 is gradually reduced by feeding-back the blowing resistance value detected by the blowing resistance sensor to the blower 12 correspondingly to the gradual increase of the blowing resistance accompanied by the processing of blowing/packing the opened/mixed material into the die 20. Thereby, the uniformity of packing density of the opened/mixed material into the die 20 is secured.