Method of milling to form highway depressions

摘要

The forming of sonic noise alert pattern, (SNAP), type depressions using a milling through procedure. A cutting head, having a smaller diameter than would fit the resultant depression, is used. Elevational control of the cutting head is regulated by passage across the surface under treatment. Repetitive cycling of this elevational control is used to install a series of depressions. The elevational control results in a gradual lowering and gradual raising of the cutting head. During cutting a significant longitudinal distance is traveled by the cutting head. Cam wheels are disclosed for providing the elevational control. Various transfer means are discussed to transfer the elevational control to the cutting head. These include direct transfer and reverse transfer. Proportional transfer is explained with examples given. Example machines are detailed capable of practicing the invention.