Windup window shade with warping compensation

摘要

A windup window shade has a windup shaft and a window shade web fastened on it. The window shade web is provided with a traction rod, which is moved at both ends by means of drive members along the guide rails. A compensating device is provided to compensate assembly tolerances or shape tolerances, which assures that too great tensions extending parallel with the windup shaft do not occur in the window shade web, which would lead to obliquely extending waves in the extended window shade web.