Abstract: Water flooding at the cathode of a fuel cell is a common problem in fuel cells. By integrating an electroosmotic (EO) pump to remove product water from the cathode area, fuel cell power can be increased. Integration of EO pumps transforms the designs of air channel and air breathing cathodes, reducing air pumping power loads and increasing oxidant transport. Hydration of gas streams, management of liquid reactants, and oxidant delivery can also be accomplished with integrated electroosmotic pumps. Electroosmotic pumps have no moving parts, can be integrated as a layer of the fuel cell, and scale with centimeter to micron scale fuel cells.

Abstract: A bistable minivalve includes a movable component, an actuator that is electrostatically, magnetically, or mechanically coupled to the movable component for controllably switching the movable component between open and closed states, and a casing providing structural support. The movable component has an actuation surface [300] movably positioned in the valve conduit and a bistable element attached to the actuation surface providing mechanical stability to the open and closed states of the movable component. The bistable element may be realized as a pair of elastic buckling beams [302, 304] attached at their midpoints to opposite sides of the actuation surface. Optionally, there may also be elastic support beams [306, 308] attached at their endpoints to the actuation surface and attached at their midpoints to the elastic buckling beams.

Abstract: Water flooding at the cathode of a fuel cell is a common problem in fuel cells. By integrating an electroosmotic (EO) pump to remove product water from the cathode area, fuel cell power can be increased. Integration of EO pumps transforms the designs of air channel and air breathing cathodes, reducing air pumping power loads and increasing oxidant transport. Hydration of gas streams, management of liquid reactants, and oxidant delivery can also be accomplished with integrated electroosmotic pumps. Electroosmotic pumps have no moving parts, can be integrated as a layer of the fuel cell, and scale with centimeter to micron scale fuel cells.

Abstract: A bistable minivalve includes a movable component, an actuator that is electrostatically, magnetically, or mechanically coupled to the movable component for controllably switching the movable component between open and closed states, and a casing providing structural support. The movable component has an actuation surface [300] movably positioned in the valve conduit and a bistable element attached to the actuation surface providing mechanical stability to the open and closed states of the movable component. The bistable element may be realized as a pair of elastic buckling beams [302, 304] attached at their midpoints to opposite sides of the actuation surface. Optionally, there may also be elastic support beams [306, 308] attached at their endpoints to the actuation surface and attached at their midpoints to the elastic buckling beams.

Abstract: The present invention provides a miniature gas turbine engine for power generation. The engine has a highly integrated unitary rotor shaft where turbine, compressor and shaft are made in one piece in one fabrication process. The turbine and compressor are positioned back to back on the shaft in an overhung configuration, allowing the front bearings to be located in the cold zone of the engine. Preferably, the Mold SDM fabrication technique is utilized to make the unitary rotor shaft in one monolithic part out of ceramics such as silicon nitride, eliminating the need for post process assembly while strengthening the integrity, reliability, and performance of the unitary rotor shaft. Integrated with a permanent magnet in the unitary rotor shaft, the miniature gas turbine engine can generate electric power of 1 kW or less. Additionally, the axial length of the miniature gas turbine engine is about 100 mm or less.

Abstract: In a micro gas turbine engine, a capacitive sensor is used for measuring a tip clearance of a radial compressor section thereof, and an actuator is used for axially displacing a rotor shaft in response to an output from the capacitive sensor. Because the capacitive change gives an accurate measure of the size of the tip clearance, a particularly high sensitivity can be achieved in parts where the tip clearance is small, thereby providing a highly precise tip clearance control.

Abstract: The present invention provides a miniature gas turbine engine for power generation. The engine has a highly integrated unitary rotor shaft where turbine, compressor and shaft are made in one piece in one fabrication process. The turbine and compressor are positioned back to back on the shaft in an overhung configuration, allowing the front bearings to be located in the cold zone of the engine. Preferably, the Mold SDM fabrication technique is utilized to make the unitary rotor shaft in one monolithic part out of ceramics such as silicon nitride, eliminating the need for post process assembly while strengthening the integrity, reliability, and performance of the unitary rotor shaft. Integrated with a permanent magnet in the unitary rotor shaft, the miniature gas turbine engine can generate electric power of 1 kW or less. Additionally, the axial length of the miniature gas turbine engine is about 100 mm or less.

Abstract: A powder molding machine capable of providing a uniform density of molding powders filled in a molding cavity of a die for improving the strength of molded products includes a die, upper and lower punches and a feeder, and is further provided with a feeder driving unit, which reciprocates a feed shoe between an advanced position at which molding powder is supplied to the die and a retracted position at which no interference occurs during a pressing operation by the punches. The feed driving unit includes a mechanism for enabling the feeder shoe to pass over the die and also to be swung in left and right directions while retracting and while still over the die.