Pumping takes place within the micro-pump as a result of the deformation of a plate (12) using a piezo-electric pad (13). The deformation produces a variation in volume within a pumping chamber (15) defined inside a plate (11) which is made of a material which can be machined using photolithographic...http://www.google.com/patents/US5224843?utm_source=gb-gplus-sharePatent US5224843 - Two valve micropump with improved outlet
