US Patent 7814958 Roll-up sunroof shade

A roll-up sunroof shade is provided that includes two guide rails running along the sides of the shade sheet. The shade sheet is cut wider than corresponds to the clear distance between the guide rails. While being pulled out, the shade sheet is forced by an appropriate geometry at the inlet end of the guide rails to form a tube-like loop around a piping member that moves along with it. Due to the wrapping of the piping member, the shade sheet is held in place perpendicular to the longitudinal extent of the guide rail.