Schwaab, G.G.SchwaabGramann, U.U.GramannLawrenz, W.W.LawrenzStock, A.A.Stock2022-03-082022-03-081999https://publica.fraunhofer.de/handle/publica/304296NOVELTY - The surface contact detection method uses an ultrasonic wave field which is propagated through the dispensed fluid medium delivered by a fluid dispenser (1), with detection of a variation in the attenuation and/or reflection characteristics of the ultrasonic waves for indicating contact between the fluid medium and n object surface, for provision of a stop signal for the dispenser. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for a device for detecting contact between a fluid medium and an object surface. USE - The surface contact detection method is used with an adhesive dispenser for fully automatic delivery of adhesive to discrete points on an object surface, e.g. a flat substrate. ADVANTAGE - The surface contact detection method allows precise control of the quantity of dispensed liquid. DESCRIPTION OF DRAWING(S) - The figure shows a cross-section through a device for detecting contact between a dispensed liquid and an object surface. Fluid dispenser 1de608670patent1997-19748317