Metering system for hot melt adhesives with variable adhesive volumes

摘要

A hot melt adhesive material dispensing system comprises two separate and independent rotary, gear-type metering pumps, or two separate and independent sets of pumps, which are able to output precisely metered amounts of hot melt adhesive material. The hot melt adhesive materials discharged are able to be independently outputted through suitable output devices onto a substrate to result in different outputted volumes of the hot melt adhesive material in accordance with predeterminedly desired patterns, or at predeterminedly desired locations. The hot melt adhesive materials may also have their volumetric outputs combined such that the discharged or outputted volumes of the hot melt adhesive material onto the substrate may be, for example, twice the outputted volumes of the hot melt adhesive outputted onto the substrate from only one of the two pumps, or from only one of the two pumps.

主权项

1. A fluid dispensing system, comprising:
a supply of fluid to be dispensed; an output device having at least one dispensing nozzle; at least two pumps for fluidically pumping fluid from said supply of fluid to said at least one dispensing nozzle; and valve means comprising a first valve positioned downstream from each of said at least two pumps and upstream from said at least one dispensing nozzle, said valve means further comprising a second valve positioned downstream from only one of said at least two pumps, said valve means for permitting said fluid dispensing system to dispense a varied volume of fluid through THREE dispensing states, a FIRST OFF state wherein said valve means is CLOSED with respect to both of said at least two pumps such that fluid outputs from both of said at least two pumps is prevented from reaching said at least one dispensing nozzle, a SECOND PARTIAL VOLUME state wherein said valve means is CLOSED with respect to a first one of said at least two pumps but OPENED with respect to a second one of said at least two pumps so as to permit the fluid output from said second one of said at least two pumps to reach said at least one dispensing nozzle, and a THIRD FULL VOLUME state wherein said valve means is OPENED with respect to both of said at least two pumps so as to permit the fluid outputs from both of said at least two pumps to reach said at least one dispensing nozzle, wherein the supply of fluid to the at least two pumps is a common supply source of fluid that is common to the at least two pumps.