| 摘要 |
A severing organ for trimming the width of a curtain of coating material poured onto an impingement site on a substrate, in particular a printed circuit board, to be coated and being moved at a distance below the foot end of the severing organ transverse to the direction of the flow of the curtain consists of a single separating element whose upper end is designed as a knifelike sharp severing edge. The side of the separating element turned toward the central region of the poured curtain is an uninterrupted, smooth wall surface which extends in only one plane from the severing edge in the direction toward the foot end of the separating element, forming a lower foot-end edge therewith, and has an inclination relative to the perpendicular which can be so adjusted that the trimmed central region of the poured curtain flows laminarly downward being laterally widened along the inner wall surface to become detached at the lower foot-end edge, and impinges directly with nearly the same widening onto the substrate to be coated, whereby a coating layer is deposited on the substrate with formation of only a narrow marginal bead having at most twice the height of the still undried layer on the substrate.
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