Patent ID: 10843222

Abstract:
A high speed granule delivery system and method is disclosed for dispensing granules in intermittent patterns onto a moving asphalt coated strip in the manufacture of roofing shingles. The system includes a granule hopper and a rotationally indexable pocket wheel in the bottom of the hopper. A series of pockets are formed in the circumference of the wheel and the pockets are separated by raised lands. A seal on the bottom of the hopper seals against the raised lands as the wheel is indexed. In use, the pockets of the pocket wheel drive through and are filled with granules in the bottom of the hopper. As each pocket is indexed beyond the seal, it is exposed to the moving asphalt coated strip below and its granules fall onto the strip to be embedded in the hot tacky asphalt. The speed at which the wheel is indexed is coordinated with the speed of the asphalt coated strip so that granules and strip are moving at about the same forward speed or at a preselected ratio of speeds when the granules fall onto the strip. Well defined patterns of granules are possible at high production rates.