Abstract: A bottom bar apparatus for a door curtain includes a bottom bar mountable on a lower end of the curtain and two bar connectors for slidably connecting opposite ends of the bar to guide members mounted along sides of the door opening. The apparatus includes two pivot mechanisms each joining a respective one of the bar connectors to a respective end of the bar. Each mechanism includes a pivot shaft and a shaft receiver into which the shaft extends. One of the shaft and the receiver is connected to a respective one of the bar connectors and the other is mounted on the bottom bar. At least one stop device is arranged to limit pivotal movement of the bar and each is mounted on one of the group consisting of the pivot mechanism and the bar connector. Pivotal movement of the shaft is restricted when the curtain is subject to windload.

Abstract: A roll-up door assembly including a flexible curtain made of synthetic rubber or fabric, a curtain winding mechanism and two guide members which extend vertically on opposite sides of the doorway. Side edge sections of the curtain are movable in respective guide members. Each guide has inner and outer wall sections with each wall section having an inwardly projecting, longitudinal rib. The two ribs of each guide form an elongate slot that receives a side edge section of the curtain. Spaced-apart pairs of curtain lock members are mounted on and distributed along each side edge section of the curtain. The lock members of each pair are positioned opposite one another on front and rear surfaces of the curtain respectively. The combined thickness of each pair of lock members and the curtain exceeds the width of the elongate slot.