摘要 |
A method of providing transverse elements to be arranged in a consecutive series side by side on a driving belt with curved surfaces by which they support the driving belt. The surfaces obtain a curvature by replacing the driving belt by an endless grinding band having grinding material on its inner side engaging the said surfaces and running the whole on two pulleys, one of which has a smaller diameter than the other one. The grinding band has longitudinal zones with different abrasing capacities, for example by providing the band with a longitudinal range of gaps in its middle zone. In this way the supporting surfaces obtain simultaneously a curvature in the running direction of the belt and in a direction opposite thereto. |