Abstract: A dock door assembly and a dock door assembly kit are provided for use in a dock door opening for installation in a warehouse. The dock door assembly comprises a pair of vertical tracks, with each vertical track configured to be attached to a wall along opposing lateral sides of the dock door opening. The dock door assembly also comprises a multiple, horizontal section door characterized by a vertical height when closed and mounted on the pair of vertical tracks. The dock door assembly further comprises a spring shaft assembly and a pair of headplates with each headplate having a U-shaped opening to receive each end of a torsion shaft. Further, the dock door assembly may comprise a pair of door cables and a pair of corner cable attachments connecting each door cable to the spring shaft assembly.

Abstract: A door strut construction includes a strut having a top cross wall connecting lateral side walls that are part of a truncated isosceles triangle and wherein the lateral cross wall joins first and second spaced pylons attached to the top edge of the side walls and further wherein the bottom edge of the side walls include projecting plate members having upstanding, outside lips for reinforcement. The strut further includes lateral ribs positioned in the upper half region of the side walls to improve torsion resistance.

Abstract: A door strut construction includes a strut having a top cross wall connecting lateral side walls that are part of a truncated isosceles triangle and wherein the lateral cross wall joins first and second spaced pylons attached to the top edge of the side walls and further wherein the bottom edge of the side walls include projecting plate members having upstanding, outside lips for reinforcement. The strut further includes lateral ribs positioned in the upper half region of the side walls to improve torsion resistance.

Abstract: A door assembly having articulated segments includes at least one support assembly for bracing the door assembly against lateral forces. This support assembly includes guide members secured to the door segments and articulated locking members disposed in sliding relation with the guide members. The locking members move between a first predetermined position in which they allow the door segments to pivot with one another and a second position in which they bridge the door segments and prevent them from pivoting with one another.