Patent ID: 6508196
Filing Date: 2003-01-21
Classification: B05B,B05C,B23K,Y10T

Abstract:
A device for controlled application of drops of solder paste with a high velocity onto a substrate, comprising:solder paste for ejection by a pressure wave through an aperture such that a drop of the solder paste will be ejected with high velocity through the aperture; a chamber for containing the solder paste to be applied, the chamber including a first wall and a second wall, the second wall being opposite the first wall; a nozzle aperture located in the first wall; an inlet opening for supplying solder paste into the chamber; a rod protruding from the second wall, the rod extending towards the first wall and having an end surface with a diameter spatially separated from but confronted immediately over the nozzle aperture to trap the solder paste between the end surface and the nozzle aperture, the diameter of the end surface of the rod being large compared to the nozzle aperture; and actuator means for the controlled application of drops of solder paste with a high velocity onto a substrate, the actuator means providing a controlled sudden displacement of the rod toward the first wall with a high acceleration of the end surface towards the nozzle aperture so that one drop of a defined volume can be ejected at a time, wherein the large diameter of the end surface of the rod impacts the solder paste located between the end surface and the nozzle aperture to produce a pressure wave in the solder paste such that a drop of solder paste will be ejected with a high velocity through the nozzle aperture, and said displacement causes the ejection of said one drop.