US Patent 9493984 Systems and methods to retain and refeed door curtains

An example door includes a track and a curtain that includes a leading section. The curtain is to be in a breakaway state associated with a folded condition when the lateral section in an area proximate the leading section is dislodged from the track and folded over onto a main section to define an enfolded space. The curtain is to be in the breakaway state associated with an unfolded condition when the lateral section in the area proximate the leading section is dislodged from the track but not folded over onto the main section. The example door also includes an unfolder to extend into the enfolded space as the leading section moves toward an open position while the curtain is in the folded condition.