door 10 is formed of a plurality of panels 11 through 20 which are hinged together with alternate hinges being on the inner side of the door and designated as hinges 21 between panels 11 and 12 hinges 22 between panels 13 and 14 hinges 23 between panels 15 and 16 hinges 24 between panels 17 and 18 and hinges 25 between panels 19 and 20 hinges on the front edges of the door are provided between the panels and alternate between the hinges 21 through 25 thus panels 12 and 13 are connected by hinges 26 panels 14 and 15 are connected by hinges 27 panels 16 and 17 are connected by hinges 28 and panels 18 and 19 are connected by hinges 29 rollers are supported between panels 12 and 13 panels 14 and 15 panels 15 and 16 and panels 18 and 19 these rollers are supported on roller shafts 31 32 33 and 34 which respectively carry rollers 35 36 37 and 38 roller shafts 31 39 32 39 33 39 and 34 39 are supported on the opposite ends of panels 12 and 13 panels 14 and 15 panels 16 and 17 and panels 18 and 19 hinges 21 39 through 25 39 are carried on the opposite ends of the panels with hinge 21 39 being between panels 11 and 12 hinge 22 39 being between panels 13 and 14 hinge 23 39 being between panels 15 and 16 hinge 24 39 being between panels 17 and.