Patrick N. Dubois
Engineering at Pioneer Cir, Argyle, TX

5560543, Oct 1, 1996

Sep 19, 1994

8/308811

Charles V. Smith - Pantego TX
John W. Priest - Dallas TX
Patrick N. DuBois - Argyle TX

Board of Regents, The University of Texas System - Austin TX

B05B 108

2391022

Apparatus and methods for making uniformly-sized and predictably-spaced droplets from high-temperature liquids. Liquid droplet generators having electromechanical driving elements are coupled to a power supply to apply pulsed excitation forces through a wall of a delivery tube to a high-temperature liquid, e. g. , a liquid metal, epoxy, or polymer. The excitation forces generated by the driver induce capillary vibrations in the liquid within the delivery tube. Liquid jet streams having capillary vibrations when exiting an orifice break up into groups of substantially uniformly-sized liquid droplets shortly after leaving the orifice. Droplets may be produced in a uniformly-spaced series, or individually on demand in response to a single burst of force from the driving element. A heat source is also thermally coupled to the delivery tube to maintain the liquid in a high-temperature state. Embodiments using heat-sensitive elements thermally insulate those elements from the wall of the heated delivery tube and may also actively cool the elements by one or more heat exchangers.

5810988, Sep 22, 1998

Oct 1, 1996

8/722410

Charles Vincent Smith - Cedar Hill TX
John William Priest - Dallas TX
Patrick Neil DuBois - Argyle TX

Board of Regents, University of Texas System - Austin TX

B05B 100

204666

Apparatus and methods for making uniformly-sized and predictably-spaced droplets or solid microspheres from high-temperature or other liquids. Liquid droplet generators having electromechanical driving elements are coupled to a power supply to apply pulsed excitation forces through a wall of a delivery tube to a liquid, e. g. , a liquid metal, epoxy, or polymer. The excitation forces generated by the driver induce capillary vibrations in the liquid within the delivery tube, which breaks the stream into substantially uniformly-sized liquid droplets shortly after leaving the orifice. Droplets may be produced in a uniformly-spaced series, or individually on demand in response to a single burst of force from the driving element. If solid microspheres are desired, the trajectory of the emitted droplets is determined to permit the solidification prior to catching or collecting the microspheres. Solidification of the spherical drops may be accomplished by freezing, evaporation, or chemical reaction due to heat transfer, material transfer, or chemical reaction as the droplets traverse a controlled environment chamber.