Patent ID: 6326212
Filing Date: 2001-12-04
Classification: B01L,Y10T

Abstract:
Membrane actuated fluid dispensing head apparatus comprising:a dispenser housing comprising a top plate, a bottom plate, a fluid distribution plate disposed between the top and bottom plates, said top plate having fluid inlet means therethrough for admitting pressurized fluid onto and over said distribution plate, said bottom plate having a plurality of elongated hollow pipettes mounted on said bottom plate extending away from said top plate and in fluid communication with said fluid distribution plate; anda first resilient membrane disposed between said distribution plate and said bottom plate, said bottom plate having a plurality of spaced cavities thereon having outer peripheries and in fluid communication with said pipettes, said distribution plate having a plurality of spaced apertured members having outer peripheries, some of said outer peripheries of said members substantially coinciding with some of the outer peripheries of said cavities;a second resilient membrane disposed between said top plate and said distribution plate having an opening therethrough in fluid communication with both the top plate and the distribution plate;whereby, when a pressurized source of fluid is injected into said dispenser housing via said inlet means, said fluid flows under pressure over said distribution plate, out of the apertures in said members and against said membrane forcing portions of said membrane overlying said cavities down into said cavities thus displacing any fluid in said pipettes out of said pipettes, then drawing up any fluid into which said pipettes are disposed up into said pipettes when injection by said source of fluid is reversed.