Dispenser for supplying small amounts of a pasty substance for surface mounting of electronic parts

A method for dispensing small amounts of a pasty substance in the form of one of adhesive and solder paste onto printed circuit boards for surface mounting of electronic components, comprising;

• proving a generally tubular housing having a nozzle and a valve face at a lower end, and defining an inner component having an inlet for the pasty substance;
• slidably arranging a nozzle element in said housing, said nozzle element having a stroke defined by movement between points in said housing, said nozzle element including a valve needle cooperating with said valve face, said nozzle element being biased by a spring to close said valve needle against said valve face, said nozzle element being connected to a plunger arranged in a cylindrical portion of the housing;
• surrounding the housing with a tubular shell thereby defining a toroidal chamber between said housing and said shell, said toroidal chamber carrying temperature modifying fluid, said fluid being provided at an upper connector connected to a supply duct and exiting at a lower outlet so that the fluid is directed toward and touches the nozzle to modify the temperature of the nozzle and pasty substance;
• choosing the pressure under which the pasty substance is provided, whereby the pasty substance remains in the compartment when a valve comprising said valve needle and said valve face is in an open position.