The present invention relates to a cover for covering a volume and/or a space, particularly a pit cover. The cover (2) comprises displacement elements (13), at least one edge region (31), and a displacement unit (15). The displacement elements (13) extend at least in areas over the space (16) to be covered and are disposed substantially parallel to each other. The displacement elements (13) are ea...

A rolling door having a door leaf and guides arranged on both sides, each of which includes a vertical portion and a spiral portion, wherein the door leaf is received in the spiral portions in the form of non-contacting winding layers when the rolling door is in the opened condition. A drive mechanism for operating the rolling door has a motor, a drive shaft and drive organs. The drive organs are ...