Wind=powered advertising rotor with promotion surfaces

摘要

The wind impingement or loading faces comprise internally concave surfaces (5) forming halved hollow bodies or bodies which are open to one side (1) and which rotate in top and bottom bearings (13) round an axis (7). The rotation speed of the bodies is limited by a brake-fitted device arranged in the mounting plate. The brake can move axially upwards or again speed is limited by a ball-bearing. The walls of the bodies (6,1) have opposed neck areas asymmetrical to the axes of symmetry of the respective hollow bodies (1), using the necks to enable the bodies to rotate on their axis (7). The concave surfaces of the two bodies face towards one another and the fixed axis (7) passes through one of the focal points of the ellipse forming the line of intersection of the two hollow bodies.