Membrane dispensing head apparatus and method for dispensing liquid

Abstract

A membrane actuated fluid dispensing head apparatus and method for dispensing fluids. The dispenser housing has a top plate, a bottom plate, and a fluid distribution plate disposed between the top and bottom plates. The top plate has fluid inlet means therethrough for admitting pressurized fluid over the distribution plate, the bottom plate having a plurality of elongated hollow pipettes thereon extending away from the top plate and in fluid communication with the fluid distribution plate. A first resilient membrane is disposed between the fluid distribution plate and the bottom plate, the bottom plate having a plurality of spaced cavities thereon having outer peripheries and in fluid communication with the pipettes. A second resilient membrane is disposed between the top plate and the distribution plate having an opening therethrough. The fluid distribution plate has a plurality of spaced apertured members having outer peripheries, some of the outer peripheries of the members substantially coinciding with some of the outer peripheries of the cavities whereby, when a pressurized source of fluid is injected into the dispenser housing via the inlet means, the fluid flows under pressure over the fluid distribution plate, out of the apertures in the members and against the membrane forcing portions of the membrane down into the cavities and out the pipettes.