Apparatus for spreading foam material

Claim 1

Coating apparatus for spreading foam material substantially uniformly in thickness and relatively free of undesirable air bubbles, blisters, or blotches, in the form of large or irregular spots or blemishes, across the full width of continuously advancing sheet material comprising: a coating manifold for receiving foam material having a predetermined density and under a pressure of less than about 5 pounds per square inch gauge; a top plate clamped in air-tight fashion to the top of said coating manifold to prevent air from entering said coating manifold during use of the same; means to substantially completely fill said coating manifold with said foam material at said predetermined density and under said pressure; means to maintain the predetermined density of said foam material in said coating manifold substantially constant from point of entry thereto to point of exit therefrom; means comprising a pair of sloping or slanting walls which gradually and uniformly converge to form a nozzle having a relatively long, narrow slit, one of said pair of sloping or slanting walls being disposed at an angle of from about 4° to about 16° to the direction of movement of said continuously advancing sheet material for delivering said foam material from said coating manifold and spreading said foam material substantially uniformly in thickness and relatively free of undesirable air bubbles, blisters, or blotches, in the form of large or irregular spots or blemishes, across the full width of said continuously advancing sheet material passing immediately adjacent said delivering means; and means substantially in contact with the other of said sloping or slanting walls of said delivering means to regulate and control the amount and the thickness of said foam material being spread on said continuously advancing sheet material, whereby the time-exposure to air of said foam material before being spread on said continuously advancing sheet material is kept to a minimum.