Method and apparatus for applying a viscous fluid to a substrate

Claim 1

A head assembly for applying a smooth coating of a high viscousity liquid to a substrate moved relative thereto, comprising, an upstream plate and a downstream plate with means spacing said plates apart defining a passage of uniform dimension therebetween, extending across a major portion of the plates, means adapted to communicate between a source of fluid supply and a back portion of said passage, a generally V-shaped reservoir communicating with a front of said passage, the reservoir including enlarged portions upstream and downstream of the passage, definedby a slanted face formed in the trailing edge of the upstream plate and a rounded edge formed in the leading edge of the downstream plate, said plates otherwise terminating in smooth, wide substrate contacting surfaces bounding the reservoir with the downstream edge of the downstream plate being formed at an acute angle with respect to the smooth surface thereof, means for mounting said head assembly for pivotable, self-aligning movement with respect to said substrate, and means for moving said head assembly back and forth in an oscillating motion with respect to said substrate.