Abstract: MEMS Device having Electrothermal Actuation and Release and Method for Fabricating. According to one embodiment, a microscale switch is provided and can include a substrate and a stationary electrode and stationary contact formed on the substrate. The switch can further include a movable microcomponent suspended above the substrate. The microcomponent can include a structural layer including at least one end fixed with respect to the substrate. The microcomponent can further include a movable electrode spaced from the stationary electrode and a movable contact spaced from the stationary electrode. The microcomponent can include an electrothermal component attached to the structural layer and operable to produce heating for generating force for moving the structural layer.

Abstract: In a microactuator having substantially parallel beams, the free ends of the beams are detached from the substrate and rigidly interconnected with one another. Differential thermal expansion of the beams causes deflection of the free ends as a unit laterally away from the thermally expanded beam. Depending on the choice of thermally expanded beam, the deflection can be either in or out of the plane parallel to the substrate. Selective heating is achieved for example by passing electric current through a pair of beams in series. Each beam has an independent electrical contact pad at the base end, and all beams are connected together electrically at the free end. A voltage is applied across the selected beam pads, whereas the non-selected beam pads are disconnected. Multiple microactuators can be combined cooperatively, e.g., to move a stage in a plurality of directions.

Abstract: A regulated power supply includes a pyroelectric capacitor. Such a power supply can be incorporated into an integrated circuit.

Abstract: The solar energy converter comprises an electron emitter and an electron collector. They are provided separate from each other in a vacuum vessel. Solar energy in a wide range of sunlight spectrum can be efficiently converted into electric energy by moving electrons from the electron emitter to the electron collector.

Abstract: The present invention embodies a solid state thermionic energy converter and is directed to a method and apparatus for conversion of thermal energy to electrical energy, and electrical energy to refrigeration. The present invention maintains a thermal separation between an emitter and a collector through a fractional surface contact of decreasing cross-sectional area towards the point of contact. The fractional surface contacts may be associated with the emitter, a barrier, or the collector. Maintaining a thermal separation between the emitter and the collector provides for ballistic electron transport through the barrier and reduces the transport of electrons through thermal conductivity. Hence, the efficiency is increased through the collection of ballistic electrons and the reduction of thermal conductivity electrons which cannot be collected. The inventive principle works for hole conductivity, as well as for electrons.

Abstract: A microelectromechanical (MEMS) device is provided that includes a microelectronic substrate, a microactuator disposed on the substrate and formed of a single crystalline material, and at least one metallic structure disposed on the substrate adjacent the microactuator While the MEMS device can include various microactuators, one embodiment of the microactuator is a thermally actuated microactuator that may include a pair of spaced apart supports disposed on the substrate and at least one arched beam extending therebetween. Thus, on actuation, the microactuator moves between a first position in which the microactuator is spaced apart from the at least one metallic structure to a second position in which the microactuator operably engages the at least one metallic structure.

Abstract: A microelectricalmechanical system (MEMS) digital isolator may be created in which an actuator such as an electrostatic motor drives a beam against a predefined force set, for example, by another electrostatic motor. When the threshold of the opposing force is overcome, motion of the beam may be sensed by a sensor also attached to the beam. The beam itself is electrically isolated between the locations of the actuator and the sensor. The structure may be incorporated into integrated circuits to provide on-chip isolation.

Abstract: An actuator assembly and method for making and using an actuator assembly. In one embodiment, the assembly includes an actuator body having an actuator channel with a first region and a second region. An actuator is disposed in the actuator channel and is movable when in a flowable state between a first position and a second position. A heater is positioned proximate to the actuator channel to heat the actuator from a solid state to a flowable state. A source of gas or other propellant is positioned proximate to the actuator channel to drive the actuator from the first position to the second position. The actuator has a higher surface tension when engaged with the second region of the channel than when engaged with the first region. Accordingly, the actuator can halt upon reaching the second region of the channel due to the increased surface tension between the actuator and the second region of the channel.

Abstract: A multi-stage cooler is formed from monolithically integrated thermionic and thermoelectric coolers, wherein the thermionic and thermoelectric coolers each have a separate electrical connection and a common ground, thereby forming a three terminal device. The thermionic cooler is comprised of a superlattice barrier surrounded by cathode and anode layers grown onto an appropriate substrate, one or more metal contacts with a finite surface area deposited on top of the cathode layer, and one or more mesas of different areas formed by etching around the contacts to the anode layer. The thermoelectric cooler is defined by metal contacts deposited on the anode layer or the substrate itself. A backside metal is deposited on the substrate for connecting to the common ground.

Abstract: A thermotunneling converter is disclosed comprising a pair of electrodes having inner surfaces substantially facing one another, and a spacer or plurality of spacers positioned between the two electrodes, having a height substantially equal to the distance between the electrodes, and having a total cross-sectional area that is less than the cross-sectional area of either of the electrodes. In a preferred embodiment, a vacuum is introduced, and in a particularly preferred embodiment, gold that has been exposed to cesium vapor is used as one or both of the electrodes. In a further embodiment, the spacer is made of small particles disposed between the electrodes. In a yet further embodiment, a sandwich is made containing the electrodes with an unoxidized spacer. The sandwich is separated and the spacer is oxidized, which makes it grow to a required height whilst giving it insulatory properties, to allow for tunneling between the electrodes.

Abstract: When the temperature of pyroelectric film is increased from low to high near its phase transition temperature its ability to hold electrical charge on its surfaces diminishes, and the charge can be drawn as current through an external load resistor. Once the film temperature reaches a steady temperature, no more power can be drawn. However, if the film temperature is lowered again, it will restore charge on the film surfaces and the pyroelectric conversion process can be repeated. Because pyroelectric conversion depends on the degree of temperature change and the repetition rate of the process, the faster the cycling the more power it can generate by converting heat to electric power. An improved apparatus and method is disclosed for converting heat to electrical energy with a multi-layer stack of thin pyroelectric films. The pyroelectric film surface is cycled between higher and lower temperatures by the displacement of higher and lower temperature fluid over the film surface.

Abstract: A cost-effective tunable optical component uses entropic, rather than enthalpic, materials to provide a compliant member that supports the optical element and is driven by an electrostatic actuator. Entropic materials exhibit an entropic plateau region over a wide frequency range with a Young's modulus much lower than enthalpic materials, linear elastic behavior over a wide deformation range, and, in certain geometries, energy and stress behavior that tend to stabilize the optical element during deformation. The compliant member can be configured in a variety of geometries including compression, tension, tensile/compressive and shear and of a variety of materials including elastomers, aerogels or other long chained polymers.

Abstract: Microminiature thermionic converters (MTCs) manufactured using MEMS manufacturing techniques including chemical vapor deposition, and having high energy-conversion efficiencies and variable operating temperatures. The MTCs of the invention incorporate cathode to anode spacing of about 1 micron or less and use cathode and anode materials having work functions ranging from about 1 eV to about 3 eV. The MTCs of the present invention have maximum efficiencies of just under 30%, and thousands of the devices can be fabricated at modest costs.

Abstract: Hybrid combustion power systems comprising multiple direct energy conversion devices are disclosed, which devices (12, 14, 16) are preferably combined with a Rankine cycle containing a steam turbine (114), where combustion air (A) may be continuously preheated by an optional air heater (58), then by the waste heat of a low temperature direct energy conversion device (16) such as an alkali metal thermoelectric converter (AMTEC), and finally by the waste heat of a high temperature direct energy conversion device (12) such as an AMTEC, where the AMTECs include electrolyte (36) may include a condenser located in substantially the same geometrical plane as the AMTEC electrolyte (36) and thermally insulated from the electrolyte.

Abstract: The present invention embodies a solid state thermionic energy converter and is directed to a method and apparatus for conversion of thermal energy to electrical energy, and electrical energy to refrigeration. The present invention maintains a thermal separation between an emitter and a collector through a fractional surface contact of decreasing cross-sectional area towards the point of contact. The fractional surface contacts may be associated with the emitter, a barrier, or the collector. Maintaining a thermal separation between the emitter and the collector provides for ballistic electron transport through the barrier and reduces the transport of electrons through thermal conductivity. Hence, the efficiency is increased through the collection of ballistic electrons and the reduction of thermal conductivity electrons which cannot be collected. The inventive principle works for hole conductivity, as well as for electrons.

Abstract: The present invention provides actuators and actuator devices that take advantage of a strain gradient variation of an actuator element between a first phase and a second phase. The actuator elements can be positioned in any type of shape. For instance, the actuator element in the first phase can be any type of curved, non-linear or irregular shape as long as a strain gradient along a cross-section of the actuator element can be established. The actuator element in the second phase is positioned in a different shape when compared to the first phase as long as it is in a direction to minimize the strain gradient. Different actions can be generated such as a rotary movement, a linear movement, an expanding movement, or a combined linear and rotary movement. The actuator element could also be configured to generate a linear movement by combining contraction and strain gradient variation.

Abstract: A micrometer sized multi-directional thermal actuator capable of repeatable and rapid displacement in a substantially horizontal direction, a substantially vertical direction, and/or a combination thereof. The multi-directional thermal actuator constructed on a surface of a substrate includes three or more beams each cantilevered from one or more anchors at a first end to extend generally parallel to the surface of the substrate. A member mechanically and electrically couples the distal ends of the beams. Application of current to a circuit comprising combinations of any two or more of the beams displaces the member in one of three or more non-parallel radial directions, respectively.

Abstract: The present invention is a thermoelectric cell for supplying an electric current. Two embodiments of the cell each comprise only one active component, a non-metallic electron emitter means, one embodiment built with a non-metallic substrate, a second embodiment encapsulated by a housing means, and a third embodiment wherein the emitter means is capable of standing alone and is either metallic or non-metallic.

Abstract: Methods of manufacturing microminiature thermionic converters (MTCs) having high energy-conversion efficiencies and variable operating temperatures using MEMS manufacturing techniques including chemical vapor deposition. The MTCs made using the methods of the invention incorporate cathode to anode spacing of about 1 micron or less and use cathode and anode materials having work functions ranging from about 1 eV to about 3 eV. The MTCs also exhibit maximum efficiencies of just under 30%, and thousands of the devices can be fabricated at modest costs.

Abstract: Modules of assembled microminiature thermionic converters (MTCs) having high energy-conversion efficiencies and variable operating temperatures manufactured using MEMS manufacturing techniques including chemical vapor deposition. The MTCs incorporate cathode to anode spacing of about 1 micron or less and use cathode and anode materials having work functions ranging from about 1 eV to about 3 eV. The MTCs also exhibit maximum efficiencies of just under 30%, and thousands of the devices and modules can be fabricated at modest costs.

Abstract: Heat generated by a fuel burning lantern is conducted to one operative surface of a solid state, thermoelectric converter. A heat sink, in contact with the module's other operative surface dissipates heat from the other surface creating a temperature differential between the two surfaces. In response to this differential, the thermoelectric converter generates direct current which can be used to energize a small radio or other small electric devices or appliances. Also, conventional lanterns can be retrofitted with a converter, according to this invention.

Abstract: Solid state thermionic energy converter semiconductor diode implementation and method for conversion of thermal energy to electric energy, and electric energy to refrigeration. In embodiments of this invention a highly doped n* region can serve as an emitter region, from which carriers can be injected into a gap region. The gap region can be p-type, intrinsic, or moderately doped n-type. A hot ohmic contact is connected to the n*-type region. A cold ohmic contact serves as a collector and is connected to the other side of the gap region. The cold ohmic contact has a recombination region formed between the cold ohmic contact and the gap region and a blocking compensation layer that reduces the thermoelectric back flow component. The heated emitter relative to the collector generates an EMF which drives current through a series load. The inventive principle works for hole conductivity, as well as for electrons.

Abstract: A device and method for generating a torque, by using waste or otherwise underutilized or unutilized thermal energy. A rotor for an electrical engine is driven to rotate using such thermal energy. The rotor includes a hollow central tube with endplates rotatably mounted thereon. A plurality of magnets and elongated members extend between the endplates. A wire loop made of shape memory effect material is wound about the central tube and each of the elongated members. The rotor operates in cooperation with a stator in which a coil is provided.

Abstract: Electrical energy generating system includes a generator being subject to a first temperature at a first location and a second temperature at a second location, the first temperature differing from the second temperature. The generator further includes a first and a second material, mutually differing galvanically, which are mutually connected in a galvanic conducting manner in two separated interface locations, such that they are connected in an electrical circuit to which an electricity consumer is connected, wherein the separated interface locations are at the first and second locations, such that the materials generate electricity by the Seebeck-Peltier-Thomson effect, supplying the electricity consumer.

Abstract: A power generation system. The system includes a magnetically-actuated turbine having a rotating shaft and a generator connected to the turbine. The generator includes a rotor connected to the rotating shaft, a stator co-axially aligned with the rotor, at least one brush connected to the rotor and extending to an inner surface of the stator, at least one thermoelectric junction on an outer surface of the stator, and a hard magnetic casing co-axially aligned with the stator.

Abstract: In embodiments of the present invention, a microelectromechanical actuator includes a beam having respective first and second ends attached to a substrate and a body disposed between the first and second ends having a sinuous shape. The body includes a portion operative to engage a object of actuation and apply a force thereto in a direction perpendicular to the beam responsive to at least one of a compressive force and a tensile force on the beam. The sinuous shape may be sinusoidal, e.g., a shape approximating a single period of a cosine curve or a single period of a sine curve. The beam may be thermally actuated or driven by another actuator. In other embodiments, a rotary actuator includes first and second beams, a respective one of which has first and second ends attached to a substrate and a body disposed between the first and second ends. Each body includes first and second oppositely inflected portions.

Abstract: Lockable microelectromechanical actuators include a microelectromechanical actuator, a thermoplastic material that is coupled to the microelectromechanical actuator to lock the microelectromechanical actuator, and a heater that melts the thermoplastic material to allow movement of the microelectromechanical actuator. When the thermoplastic material solidifies, movement of the microelectromechanical actuator can be locked, without the need to maintain power, in the form of electrical, magnetic and/or electrostatic energy, to the microelectromechanical actuator, and without the need to rely on mechanical friction to hold the microelectromechanical actuator in place. Thus, the thermoplastic material can act as a glue to hold structures in a particular position without the need for continuous power application. Moreover, it has been found unexpectedly, that the thermoplastic material can solidify rapidly enough to lock the microelectromechanical actuator at or near its most recent position.

Abstract: Microelectromechanical actuators include a substrate, spaced apart supports on the substrate and a thermal arched beam that extends between the spaced apart supports and that further arches upon heating thereof, for movement along the substrate. One or more driven arched beams are coupled to the thermal arched beam. The end portions of the driven arched beams move relative to one another to change the arching of the driven arched beams in response to the further arching of the thermal arched beam, for movement of the driven arched beams. A driven arched beam also includes an actuated element at an intermediate portion thereof between the end portions, wherein a respective actuated element is mechanically coupled to the associated driven arched beam for movement therewith, and is mechanically decoupled from the remaining driven arched beams for movement independent thereof.

Abstract: Spiral, sparse spiral, substantially spiral or substantially sparse spiral transducer arrays comprising capacitive micromachined ultrasonic transducer elements disposed on a silicon substrate, and ultrasound imaging systems employing same. The transducer elements are respectively coupled to a plurality of amplifiers. Imager electronics are coupled to each of the amplifiers and drives the transducer elements and/or generates an output of the spiral transducer array. The amplifiers may be located in the silicon substrate containing the transducer elements, or on a separate substrate that is interconnected to the substrate containing the transducer elements using bumps, for example. Electrical interconnection to the transducer elements may readily be achieved without interfering with the acoustic output of the transducer elements.

Abstract: A microelectromechanical device comprises first and second beam members that have respective first ends connected to anchors, and that are also connected together. The first and second beam members are connected to a dielectric tether by a first tether anchor. The microelectromechanical device further comprises a third beam member that has a first end that is connected to an anchor and that is connected to the dielectric tether by a second tether anchor. At least one of the first and the second beam members are configured to elongate when the first and/or the second beam member is heated to a temperature that is greater than a temperature of the third beam member.

Abstract: Improved microelectromechanical structures include spaced-apart supports on a microelectronic substrate and a beam that extends between the spaced-apart supports and that expands upon application of heat thereto to thereby cause displacement of the beam between the spaced-apart supports. A heater, located on the beam, applies heat to the beam and displaces with the beam as the beam displaces. Therefore, heat can be directly applied to the arched beam, thereby reducing thermal loss between the heater and the arched beam. Furthermore, an air gap between the heater and arched beam may not need to be heated, thereby allowing improved transient thermal response. Moreover, displacing the heater as the arched beam displaces may further reduce thermal loss and transient thermal response by reducing the separation between the heater and the arched beam as the arched beam displaces.

Abstract: A microelectromechanical (MEM) ratcheting apparatus is disclosed which includes an electrostatic or thermal actuator that drives a moveable member in the form of a ring gear, stage, or rack. Motion is effected by one or more reciprocating pawls driven by the actuator in a direction that is parallel to, in line with, or tangential to the path. The reciprocating pawls engage indexing elements (e.g. teeth or pins) on the moveable member to incrementally move the member along a curved or straight path with the ability to precisely control and determine the position of the moveable member. The MEM apparatus can be formed on a silicon substrate by conventional surface micromachining methods.

Abstract: Resistor networks, digital potentiometers and microelectromechanical structures that include a plurality of resistors selectable by a plurality of microelectromechanical actuators are provided. More particularly, a thermal relay type of actuator is provided as a switch which may selectively control which of the plurality of resistors is connected. In one particularly advantageous embodiment, the heater for the thermal relay and the plurality of resistors are formed from a common layer of the integrated circuit structure, such as a doped polysilicon layer, which may simplify the manufacturing process. Preferably, a thermal arched beam actuator is utilized in combination with film resistors to provide an integrated circuit device suitable for applications such as digital potentiometers.

Abstract: Microminiature thermionic converts (MTCs) having high energy-conversion efficiencies and variable operating temperatures. Methods of manufacturing those converters using semiconductor integrated circuit fabrication and micromachine manufacturing techniques are also disclosed. The MTCs of the invention incorporate cathode to anode spacing of about 1 micron or less and use cathode and anode materials having work functions ranging from about 1 eV to about 3 eV. Existing prior art thermionic converter technology has energy conversion efficiencies ranging from 5-15%. The MTCs of the present invention have maximum efficiencies of just under 30%, and thousands of the devices can be fabricated at modest costs.

Abstract: An apparatus and method for determining the rate of angular rotation of a moving body and, in particular, for alignment of the dither motion and the Coriolis acceleration sensing direction in a sensor adapted to be formed, i.e. micromachined, from a silicon substrate.

Abstract: A MEMS (Micro Electro Mechanical System) variable optical attenuator is provided that is capable of optical attenuation over a full range of optical power. The MEMS variable optical attenuator comprises a microelectronic substrate, a MEMS actuator and an optical shutter. The MEMS variable optical attenuator may also comprise a clamping element capable of locking the optical shutter at a desired attenuation position. The variable light attenuator is capable of attenuating optical beams that have their optical axis running parallel and perpendicular to the substrate. Additionally, the MEMS actuator of the present invention may comprise an array of MEMS actuators capable of supplying the optical shutter with greater displacement distances and, thus a fuller range of optical attenuation. In one embodiment of the invention, the MEMS actuator comprises a thermal arched beam actuator. Additionally, the variable optical attenuator of the present invention may be embodied in a thermal bimorph cantilever structure.

Abstract: A MEMS thermal actuator device is provided that is capable of providing linear displacement in a plane generally parallel to the surface of a substrate. Additionally, the MEMS thermal actuator of the present invention may provide for a self-contained heating mechanism that allows for the thermal actuator to be actuated using lower power consumption and lower operating temperatures. The MEMS thermal actuator includes a microelectronic substrate having a first surface and at least one anchor structure affixed to the first surface. A composite beam extends from the anchor(s) and overlies the first surface of the substrate. The composite beam is adapted for thermal actuation, such that it will controllably deflect along a predetermined path that extends substantially parallel to the first surface of the microelectronic substrate. In one embodiment the composite beam comprises two or layers having materials that have correspondingly different thermal coefficients of expansion.

Abstract: A microelectromechanical (MEMS) device is provided that includes a microelectronic substrate and a thermally actuated microactuator and associated components disposed on the substrate and formed as a unitary structure from a single crystalline material, wherein the associated components arc actuated by the microactuator upon thermal actuation thereof. For example, the MEMS device may be a valve. As such, the valve may include at least one valve plate that is controllably brought into engagement with at least one valve opening in the microelectronic substrate by selective actuation of the microactuator. While the MEMS device can include various microactuators, the microactuator advantageously includes a pair of spaced apart supports disposed on the substrate and at least one arched beam extending therebetween.

Abstract: The present invention is a thermoelectric cell for supplying electric current to an electrical load. Three embodiments of the cell are each comprised of three component means, electron emitter, electron collector/anode and cathode, or three component means, two electron emitters, and an electron collector. A fourth embodiment comprises only an electron collector means and an electron emitter means.

Abstract: A stepper motor includes the following. A rotatable hub. A first shaped memory alloy (abbreviated to SMA) rotary-driver, which when heated undergoes a shape change to rotationally couple with the hub and rotate the hub in a predetermined direction, and which can be deformed to reverse the shape change to rotationally uncouple from the hub. A first return spring connected with the first SMA rotary-driver for deforming the first SMA rotary-driver, when no longer heated, to reverse the shape change of the first SMA rotary-driver and rotationally uncouple the first SMA rotary driver from the hub. A second SMA rotary-driver, which when heated undergoes a shape change to rotationally couple with the hub and rotate the hub in the predetermined direction, and which when can be deformed to reverse the shape change to rotationally uncouple from the hub.

Abstract: A microcavity apparatus and systems for maintaining microcavity spacing over a macroscopic area. An application of this invention is a microscale generator. This microscale generator includes a first element for receiving energy; a second element, opposite the first element for transferring energy; at least one panel on either of the first element or the second element, the panel facing the other element; a device for controlling the distance between the at least one panel and the facing element to form a predetermined, sub-micron gap between the panel and the facing element for increasing energy transfer to the element for receiving; and a device, responsive to the energy transfer, for generating electricity.

Abstract: A method for building a thermionic converter comprises providing an electrode and creating a central depression of substantially uniform depth on a face of the electrode. A surface of the central depression is coated with a layer comprising a thermionic material. A second electrode comprising a face is also provided, wherein the face of the second electrode comprises a central depression of substantially uniform depth, wherein the central depression is coated with a layer comprising a thermionic material.

Abstract: The present invention is a thermoelectric cell employing, in several embodiments, single and multiple anode electron emitters, single and multiple anodes, single and multiple within-cell resistors, and single and multiple cathodes.

Abstract: A method and apparatus for controlling the temperature of a thermionic reactor over a wide range of operating power, including a thermionic reactor having a plurality of integral cesium reservoirs, a honeycomb material disposed about the reactor which has a plurality of separated cavities, a solid sheath disposed about the honeycomb material and having an opening therein communicating with the honeycomb material and cavities thereof, and a shell disposed about the sheath for creating a coolant annulus therewith so that the coolant in the annulus may fill the cavities and permit nucleate boiling during the operation of the reactor.

Abstract: A multiple cell thermionic converter having a generally tubular member of electrically conductive refractory metal with an internal cavity and a coaxial tubular envelope of electrically conductive refractory metal disposed in surrounding relationship thereto. Bodies of electrically insulating ceramic material disposed on elongated sections of facing surfaces of the tubular member and the envelope support juxtaposed emitters and collectors to provide a series of thermionic cells. Tubular metal connectors having particular aperture patterns respectively join the collector of one cell to the emitter of the next adjacent cell to create a series electrical interconnection. The aperture patterns include sets of slots in a pair of parallel planes that are perpendicular to the axis, providing necessary flexibility to accommodate thermal expansion and contraction while providing low electrical resistance and long fatigue life. Axial keyhole apertures and auxiliary slits located in a central plane may also be included.

Abstract: MEMS (Microelectromechanical System) structures are provided that are designed to rotate in response to thermal actuation or the like. In one embodiment, the MEMS rotary structure includes a hub having one or more radial spoke members that impose a rotational force upon the hub in response to applied changes in temperature. The MEMS rotary structure can also include a ring at least partially encircling the hub and connected to the hub by means of one or more hub spoke members. Controllable clockwise, counterclockwise, or both clockwise and counterclockwise rotation of the hub or ring are provided. The MEMS rotary structures can also include thermal arched beam actuators that are operably connected to the spoke member. As the temperature changes, the thermal arched beam actuators move the spoke members in order to rotate the MEMS structure.

Abstract: A thermionic paired tube bank (100) designed for use as a tubular heat exchanger for generating electricity, preferably heated by combustion products after they leave the combustor of a power plant but before they enter the turbine or steam generator portion of the power generation system. In this case the thermionics act as a topping cycle to increase the overall electrical generation efficiency. The heat could also be supplied by the products of combustion as they leave the gas turbine or steam generator in which case the thermionics would act as a bottoming cycle. The thermionic paired-tube bank comprises a plurality of paired-tube thermoelectric couples (50) and a plurality of electrical connections (66, 68).

Abstract: A micro-electromechanical device, such as a micro-sensor or micromachine, includes a movable part in the form of a cantilever or diaphragm, which is formed on a substrate. In order to recover stiction in which the movable part is fixedly adhered to the substrate, a heating element is provided on a surface of the substrate which is opposed to the movable part. The heating element can be operated upon occurrence of stiction, so as to generate heat and thereby separate the movable part from the substrate and assure a proper operation of the device. The device can be produced at a relatively low cost, and achieves a stiction recovery with a high reliability, even when the device is enclosed in a package.

Abstract: An actuator for selectively exerting a force responsive to an increase or decrease in applied electrical energy, including an electrically conductive member slideably seated within an electrically non-conductive frame, a thermally responsive and electrically conductive shape memorizing spring seated within the frame and adjacent to the member for urging the member responsive to the passage of electrical current through the shape memorizing spring. An electrically conductive contact strip is connected to the frame and extends therefrom in contact with the member such that movement of the member from the neutral position toward an optimal position will maintain the member in contact with the contact strip and wherein movement of the member to the optimal position will disconnect the member and the contact strip. A power source for generating energy is electrically connected to the contact strip and to the shape memorizing spring whereby a circuit is formed when the member is in contact with the contact strip.

Abstract: A thermionic converter having an emitter, a collector, and a source of cesium vapor is provided wherein the source of cesium vapor is differentially heated so that said source has a hotter end and a cooler end, with cesium vapor evaporating from said hotter end into the space between the emitter and the collector and with cesium vapor condensing at said cooler end. The condensed cesium vapor migrates through a porous element from the cooler end to the hotter end.