Method and Apparatus for Sharp Color Definition on the Application of Granules to Roofing Substrates

摘要

A high speed granule delivery system and method is disclosed for dispensing granules in intermittent patterns onto a moving asphalt coated substrate 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 substrate below and its granules fall onto the substrate 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 substrate so that granules and substrate are moving at about the same forward speed or at a preselected ratio of speeds when the granules fall onto the substrate. Well defined patterns of granules are possible at high production rates. A method for creating sharp linear color definition between granule patches at high line speeds also is disclosed.

主权项

1. A method of creating adjacent patches of different colored granules on an asphalt coated substrate moving in a downstream direction in the manufacturing of shingles, the method comprising the steps of:
(a) defining a series of spaced apart first areas along the asphalt coated substrate designated to receive granules of a first color and defining a series of spaced apart second areas adjacent to and between the first areas designated to receive granules of a second color; (b) conveying the asphalt coated substrate along a production path in the downstream direction at a predetermined line speed; (c) applying a partial charge of granules of the first color into the first areas to create granule patches having a sharp leading edge, an indistinct trailing edge, and leaving a portion of first areas exposed; (d) applying a full charge of granules of the second color into the second areas to create granule patches having a sharp leading edge and an indistinct trailing edge overlapping the leading edges of the patches of the first color; (e) filling the exposed portions of the first areas with granules of the first color; and (f) removing granules that overlap previously applied granules to create adjacent granule patches of different colors with sharp linear color definition between patches.