Non-contact liquid material dispenser having a bellows valve assembly and method for ejecting liquid material onto a substrate

• Main Authors: SMITH JAMES C, MESSERLY JAMES W
• Format: Patent
• Language: English
• Published: 31.07.2001
• Edition: 7
• Subjects: APPARATUS FOR APPLYING LIQUIDS OR OTHER FLUENT MATERIALS TOSURFACES, IN GENERAL; APPLYING LIQUIDS OR OTHER FLUENT MATERIALS TO SURFACES, IN GENERAL; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; MACHINE TOOLS; MEASURING; MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUIDLEVEL; METAL-WORKING NOT OTHERWISE PROVIDED FOR; METERING BY VOLUME; PERFORMING OPERATIONS; PHYSICS; SOLDERING OR UNSOLDERING; SPRAYING OR ATOMISING IN GENERAL; TESTING; TRANSPORTING; WELDING; WORKING BY LASER BEAM

An apparatus for dispensing a small amount of a viscous liquid material onto a substrate, the apparatus comprising a housing and piston positioned within the housing and having a lower surface and a flow bore extending therein, the flow bore having an inlet for receiving the viscous liquid material and an outlet. The apparatus further includes a compressible dispensing element positioned within the housing below and in liquid tight sealing engagement with the lower surface of the piston and having a passage extending therethrough, the passage having an inlet in liquid communication with the outlet of the flow bore and an outlet. The lower surface of the piston is capable of applying a force to compress the dispensing element causing the passage to at least partially close expelling a small amount of the viscous liquid material from the outlet of the passage. The apparatus has a nozzle in liquid communication with the outlet of the passage for guiding the small amount of viscous liquid material expelled from the outlet of the passage onto the substrate.