Abstract: The invention relates to a roll door unit (1 1) for covering a door opening, a roll-up door (IO) comprising this roll door unit and a specific use of the roll door unit (IO). The roll door unit (11) comprises a flexible door panel (16), a rotatable roll shaft (15) for rolling-up the flexible door panel (16), side frames (12), mounting flanges (14) for mounting the roll shaft (15) to the side frames (12), a connecting element (17) for connecting a motor unit (18) to the roll shaft (15), and supporting beams (13) for supporting the side frames (12) in mounted state and being connected or connectable to a wall or ground, whereby a longitudinal axis of the roll shaft (15) is positioned in alignment with a plane being spanned by the supporting beams (13).

Abstract: With a high performance door, preferably high speed door, for closing an opening (11), preferably in a wall (12) comprising a flexible curtain (13) to be wound and unwound on a shaft to open and close the opening (11) with a rigid bottom beam (15) attached on the lower end of said curtain (13) the risk from the bottom beam to the environment upon opening is reduced in, that the rigid bottom beam (15) comprising at least one flush side (20) at least almost flushing the curtain (13).

Abstract: In a double roll machine such as roller presses for extremely high drive power requirements without having to employ heavy and bulky drive motors with intermediate gears operating under the principles of product bed pressing, both long ends of both rollers of a double roll machine are constructed as drive journals and all four drive journals each are driven by a separate drive motor, particularly by a slip-on gearing, i.e., that the two rollers of the double roll machine be driven with a total of four drive motors with resistant and shock torque shared equally at both ends of the rollers.