Apparatus for the spot application of adhesives to continuous sheet material

Claim 1

In an apparatus for applying discontinuous dots of dry powder material in a predetermined pattern onto a substantially continuous substrate, which apparatus comprises perforated hollow roller means movable with respect to said substrate whereby to sequentially juxtapose said perforations to said substrate and to permit material in said hollow roller to pass through said perforations onto said substrate; the improvement, whereby permitting said material in dry powder form to be applied as discrEet dots through said perforations, which comprises ferromagnetic hopper means with respect to said apparatus, and magnet means disposed proximate to said substrate and said hopper means on the side of said substrate directed away from said hopper which hopper means has mouth means directed toward said substrate and in contact with the inside wall of said roller, which hopper means is canted in the upstream direction and which mouth means comprises two arms both of which are canted upstream of the leading edge of a perforation in registry therewith whereby said powder material is maintained substantially only in said hopper means and passes through only those perforations in said roller means juxtaposed to said substrate and wherein both of said mouth arms form an acute angle with the trailing surface of said roller.