Patent ID: 6550691
Filing Date: 2003-04-22
Classification: B05B

Abstract:
A reagent dispenser head for coating a substrate with multiple drops of reagent simultaneously, comprising:(a) a nozzle plate having a plurality of orifices defining an image pattern; (b) a planar piezoelectric actuator adapted for attachment to a control signal generator; and (c) a housing maintaining said nozzle plate and said piezoelectric actuator in parallel and spaced apart relation, said nozzle plate, said piezoelectric actuator, and said housing defining a fluid chamber, said housing having: (i) a back plate having an opening defined therein, said piezoelectric actuator being mounted in said opening; (ii) a front plate having a fluid inlet defined therethrough and having a front surface and a back surface; (iii) a conical well defined in the back surface of said front plate, the conical well having a window opening defined through the front surface of said front plate, said nozzle plate being disposed to cover said window opening; (iv) a shallow capillary flow channel defined in the back surface extending between the fluid inlet and said conical well; and (v) a thin, flexible, impermeable membrane disposed between said piezoelectric actuator and the well defined in the back surface of said front plate in order to prevent reagent in the well from direct contact with said piezoelectric actuator; wherein (d) said piezoelectric actuator is deformable upon receiving a trigger signal from the control signal generator so that the volume of said fluid chamber is reduced in order to coat the substrate with multiple drops of the reagent simultaneously in the image pattern defined by said nozzle plate.