US Patent 7857432 Drop generator

A drop generator includes a pressure chamber and a flexible diaphragm plate disposed on the chamber and forming a wall of the pressure chamber. A piezoelectric transducer having a bottom surface is attached to the diaphragm plate. The diaphragm plate includes a recess that forms a perimeter around the bottom surface of the transducer that partially underlies at least one edge of the bottom surface. An inlet channel is connected to the pressure chamber and configured to direct ink to the pressure chamber from a manifold. An outlet channel is connected to the pressure chamber to receive ink from the pressure chamber and has a channel axis that is perpendicular to the diaphragm plate. The outlet channel includes a first outlet channel section and a second outlet channel section. The first outlet channel section includes a plurality of subsections having alternating diameters. The second outlet channel section includes an aperture disposed at an end thereof. The second outlet channel section has a substantially continuous cross-sectional shape and a length that is greater than a length of the first outlet channel section.