Dispenser apparatus for simultaneously dispensing predetermined equal volumes of liquid including a disposable dispenser module

Claim 1

Dispenser apparatus for simultaneously providing predetermined equal volumes of liquid to each of a plurality of wells, said apparatus comprising: a disposable multiple chamber dispenser module of integral plastic construction having a top surface and a plurality of dependent walls each defining a lower chamber for alignment with a corresponding well, each chamber having an open lower nozzle end and extending upwardly to an opening in said top surface; a die plate having a plurality of concavities each having an equal volume and a mouth, and each being defined by an inner surface and corresponding to one of said chambers; a diaphragm having a portion extending across the mouth of each concavity, each said portion being movable from said mouth into substantially full surface contact with said inner surface, means for spacing said diaphragm from said top surface and forming an upper chamber which constitutes an upper extension of each lower chamber, said upper chamber having a volume that is variable by the position of said diaphragm portion; and means for moving each diaphragm portion between a first position across the mouth of its concavity and a second position wherein it is in surface contact with said inner surface, whereby the volume of each upper chamber can be changed by the same amount by selective operaton of said means for moving, said diaphragm being disposed between said die plate and said dispenser module and wherein said means for moving comprises means for providing a vacuum, said means for providing a vacuum including a vacuum manifold on said die plate, each inner surface having a plurality of vacuum openings, said means for spacing comprising a clamping plate disposed between said diaphragm and said dispenser, said clamping plate having a bottom surface, said dispenser apparatus further comprising means for sealing for forming air tight seals with the top surface of said dispenser module including a gasket sheet bonded to said bottom surface of said clamping plate to enter into a sealing relationship with said top surface of said dispenser module, said gasket sheet having an aperture in alignment with each upper chamber and its corresponding lower chamber so that the upper chambers are isolated from one another, the material of said gasket sheet not overlying any of said lower chambers, said dispenser module further including a dependent peripheral skirt terminating in a lower abutment surface for engagement by a clamp, said clamping plate also comprising an abutment surface for engagement by said clamp, said clamping plate having a first surface facing said diaphragm and said die plate has a second surface facing said diaphragm, one of said first and second surfaces having grooves and the other of said first and second surfaces having corresponding projections, the projections pushing components of said diaphragm into said grooves.