Low friction pressure seal for fabric processing chamber

Claim 1

A low-friction, low pressure seal for use in combination with a processing chamber for the continuous liquid ammonia processing of fabrics, wherein the chamber is maintained at a slight negative pressure in relation to the surrounding ambient and wherein the fabric is conveyed through the chamber with minimum tension applied at the seal, wherein the seal comprises and is characterized by a. means forming a smooth stationary rigid guide member mounted in the region of the chamber opening, for engaging, guiding and supporting one surface of the fabric web as it passes through the opening, b. said guide member extending across the full width of the opening, c. a stationary seal support mounted in spaced, parallel relation to said guide member and defining therewith a web passageway associated with said chamber opening, d. an elongated, resilient, hollow, deformable sealing member carried by said stationary seal support and extending toward said guide member, e. said deformable sealing member extending across the full width of said opening, f. a thin, flexible, web-like section of low friction material secured in normally stationary manner in a region spaced from said deformable sealing member and extending between said sealing member and said rigid guide member, g. said web-like section being urged lightly toward said guide member by said sealing member, h. said resilient sealing member being maintained free of internal inflation pressures, whereby sealing pressures applied by said sealing member are derived exclusively by limited elastic deformation of said sealing element, whereby said fabric can be advanced with a minimum of tension resulting from said seal, and i. said low pressure seal being adapted for the low resistance passage of a fabric web between and in sealed relation with said guide member and said section of low friction material.