Abstract: A door having a leaf of flexible material and held in suspension for raising and lowering within an opening has two lines attached to the lower portion of the door leaf, one line at each of its ends. The lines are also connected to a hoist means. The ends of the door leaf are guided in U-shaped forms having lateral flanges, the flanges being attached to the vertical defining surfaces of the door opening and each form carries one of the lines that extends to the hoist means. Each line is connected to its respective end of the door leaf by an intermediate release and lock means which responds to a predetermined decrease in load on the respective line to lock and hold fast the door leaf against the lateral flanges of the respective U-shaped form in any position along the door's vertical path of movement.

Abstract: A sealing device for sealing the gap between two spaced, adjacent surfaces is disclosed. The device comprises an inflatable flexible hose disposed within the gap and which, when inflated, completely fills the gap to effect a seal. The hose may be secured to one of the surfaces and will, when evacuated, lie substantially flat against this surface in an unobtrusive position.

Abstract: A method for fabricating doors having spaced sheets of flexible material with cross-memebers interposed and attached between the material. Flexible material is fed intermittently from material supplies to form both sides of the door. Between each feed step the material is connected to a cross-member in a predetermined operative position, in which the cross-member abuts a movable carrier. The positioning of the cross-member in the operative position is effected by the carrier which causes vertical material feed. The feeding of flexible material and connection of each cross-member is continued until the desired door size is accomplished.