Patent application number | Description | Published |
20110139408 | COLLECTOR-RADIATOR STRUCTURE FOR AN ELECTROHYDRODYNAMIC COOLING SYSTEM - An electrohydrodynamic fluid accelerator includes an emitter electrode and leading surfaces of a collector electrode that are substantially exposed to ion bombardment. Heat transfer surfaces downstream of the emitter electrode along a fluid flow path include a first portion not substantially exposed to the ion bombardment that is conditioned with a first ozone reducing material. The leading surfaces of the collector electrode are not conditioned with the first ozone reducing material, but may include a different surface conditioning. The downstream heat transfer surfaces and the leading surfaces can be separately formed and joined to form the unitary structure or can be integrally formed. The electrohydrodynamic fluid accelerator can be used in a thermal management assembly of an electronic device with a heat dissipating device thermally coupled to the conditioned heat transfer surfaces. | 06-16-2011 |
20110265832 | ELECTRODE CONDITIONING IN AN ELECTROHYDRODYNAMIC FLUID ACCELERATOR DEVICE - Conditioning an electrode is performed with a cleaning device for removing detrimental material from forming electrode surfaces of an electrohydrodynamic device or other ion flow generating device. A conditioning material is deposited on the electrode to at least partially mitigate erosion, corrosion, oxidations, dendrite formation on the electrode or ozone production. The conditioning material can be deposited by a wearable portion of one or more cleaning blocks or wipers. The cleaning blocks may have a composition selected to be hard enough to remove detrimental material under a selected pressure, while soft enough to be wearable to deposit a conditioning layer on the electrode surface. The conditioning material can be applied as a solid or liquid. The applied conditioning material can include at least one of silver, palladium, platinum, manganese, nickel, zirconium, titanium, tungsten, aluminum, oxides or alloys thereof, carbon, and organometallic materials that decompose under plasma conditions. | 11-03-2011 |
20110308768 | CLEANING MECHANISM WITH TANDEM MOVEMENT OVER EMITTER AND COLLECTOR SURFACES - An apparatus for tandem cleaning of an emitter electrode and collector electrode in electrohydrodynamic fluid accelerator and precipitator devices via movement of a cleaning mechanism including respective cleaning surfaces positioned to frictionally engage the emitter electrode and collector electrode. The cleaning mechanism causes the respective cleaning surfaces to travel along a longitudinal extent of the emitter electrode and, in tandem, over a major dimension of the collector electrode to remove detrimental material from respective electrode surfaces. Alternatively, the electrodes can be transited in tandem in frictional engagement with a fixed cleaning mechanism in the same or opposite directions. A conditioning material is optionally deposited on an electrode to at least partially mitigate ozone, erosion, corrosion, oxidation, or dendrite formation on the electrodes. The conditioning material can include an ozone reducer. | 12-22-2011 |
Patent application number | Description | Published |
20090261268 | IONIC FLUID FLOW ACCELERATOR - An electrohydrodynamic fluid accelerator apparatus includes a corona electrode having an axial shape and configured to receive a first voltage. The electrohydrodynamic fluid accelerator apparatus includes a collector electrode disposed coaxially around the at least one corona electrode and configured to receive a second voltage. Application of the first and second voltages on the corona electrode and the collector electrode, respectively, causes fluid proximate to the corona electrode to ionize and travel in a first direction between the corona electrode and the collector electrode, thereby causing other fluid molecules to travel in a second direction to generate a fluid stream. In at least one embodiment of the invention, the ionized fluid proximate to the emitter electrode travels in a radial direction from the corona electrode to the collector electrode, causing the other fluid molecules to travel in an axial direction to thereby generate the fluid stream. | 10-22-2009 |
20090321056 | MULTI-STAGE ELECTROHYDRODYNAMIC FLUID ACCELERATOR APPARATUS - Multi-stage electrohydrodynamic (MHD) fluid flow acceleration is described. In some embodiments, an EHD fluid accelerator apparatus includes a substrate for thermal conduction and a plurality of electrode structures for thermal conduction therethrough, wherein each electrode structure has a collector electrode portion and a corona discharge electrode portion. | 12-31-2009 |
20100003003 | OPTICAL ATTENUATOR - A tilting mirror MEMS variable optical attenuator attenuates light over a band of wavelengths with minimum wavelength dependent loss. The attenuator includes a lens that has a wedged input face and is made from a material that has high dispersion. The lens design causes different wavelengths to travel different paths through the attenuator such that wavelength dependent loss is reduced. The attenuator may be designed to have minimum wavelength dependent loss at a specified attenuation greater than zero. | 01-07-2010 |
20110308775 | ELECTROHYDRODYNAMIC DEVICE WITH FLOW HEATED OZONE REDUCING MATERIAL - A thermal management apparatus includes an electrohydrodynamic fluid accelerator energizable to motivate fluid flow. Primary heat transfer surfaces are positioned to transfer heat into the fluid flow and an ozone reducing material is positioned downstream of the primary heat transfer surfaces. Heating of the ozone reducing material by the fluid flow increases the efficacy of the ozone reducing material. A method of making a product includes positioning an emitter electrode and at least one other electrode to motivate fluid flow along a flow path when the electrodes are energized. The method further includes positioning heat transfer surfaces in the flow path to transfer heat to the fluid flow and positioning ozone reducing material downstream of the heat transfer surfaces in the flow path, the ozone reducing material selected such that heating of the ozone reducing material by the fluid flow increases ozone reducing efficacy of the ozone reducing material. | 12-22-2011 |
20120000627 | ELECTROSTATIC PRECIPITATOR PRE-FILTER FOR ELECTROHYDRODYNAMIC FLUID MOVER - Electrostatic precipitation is performed upstream of collector electrode surfaces toward which a downstream EHD fluid mover accelerates fluid flow. In this way, the upstream electrostatic precipitator (ESP) acts as a pre-filter (with low flow-impedance) and can reduce accumulation of otherwise detrimental materials on downstream electrodes and/or arcing. In some cases, pre-filtering by an upstream electrostatic precipitator may also reduce accumulation of otherwise detrimental materials on downstream heat transfer surfaces and/or ozone catalytic or reactive surfaces/materials. In some embodiments, an EHD fluid mover with an ESP pre-filter is used in a thermal management system to dissipate heat generated by a thermal source. | 01-05-2012 |
20120113590 | ELECTRONIC SYSTEM WITH EHD AIR MOVER VENTILATION PATH ISOLATED FROM INTERNAL AIR PLENUM - An electronic system including an enclosure and an internal air plenum within the enclosure. At least one component of the electronic system within the enclosure evolves heat and has a surface exposed to the internal air plenum. The enclosure has inlet and outlet ventilation boundaries together with an EHD air mover disposed therein to motivate airflow along a flow path between the inlet and outlet ventilation boundaries, wherein the flow path is substantially excluded from the internal air plenum by a barrier. | 05-10-2012 |
20120120542 | ELECTRONIC SYSTEM CHANGEABLE TO ACCOMMODATE AN EHD AIR MOVER OR MECHANICAL AIR MOVER - An electronic system is configurable to accommodate either of a mechanical air mover and an EHD air mover within an enclosure. At least one of a plurality of electronic components is selectively configurable to alternately accommodate the mechanical air mover or the EHD air mover within the enclosure. The mechanical fan or EHD is positioned to motivate air flow along a air flow path between inlet and outlet ventilation boundaries of the enclosure. A connector for a respective one of the electronic components allows for selective configuration in an alternate orientation of the respective one of the electronic components to accommodate a difference in geometry between the EHD air mover and the mechanical air mover. | 05-17-2012 |
20120120543 | ION PROTECTION TECHNIQUE FOR ELECTRONIC SYSTEM WITH FLOW BETWEEN INTERNAL AIR PLENUM AND AN EHD DEVICE - Techniques are described for integration of EHD-type air movers with electronic systems, and in particular, for limiting infiltration of ions and/or charged particulates into an internal air plenum. In some designs, it may be desirable to allow or even encourage EHD motivated air flow (whether drawn or forced) through the internal air plenum while providing a barrier to transit of ions and/or charged particulates that may be generated during EHD operation. Such a barrier may employ electrostatic forces to impede transit of ions and/or charged particulate across a vent positioned to allow air flow from or into the internal air plenum. In some cases, an electrostatic barrier may include a fluid permeable mesh or grill that spans a substantial cross-section of the vent. | 05-17-2012 |
20120205079 | ELECTRONIC SYSTEM ADAPTED FOR PASSIVE CONVECTIVE COOLING AND STAGED USE OF ELECTROHYDRODYNAMIC (EHD) AND MECHANICAL AIR MOVERS FOR QUIET FORCED CONVECTION ASSIST - Flow paths, duct work, ventilation boundaries, and/or placement of EHD and mechanical air mover within a electronic device enclosure can all affect the efficacy of a thermal management solution that seeks to provide silent air cooling over a significant thermal operating envelope with staged introduction of electrohydrodynamic (EHD) and mechanical air mover devices. For electronic devices in which it is desirable to employ passive, unforced convective cooling over a portion of the thermal operating envelope, practical designs for consumer electronics form factors may be quite sensitive to flow path, duct work and ventilation boundary design as well as to the placement of EHD and mechanical air mover components relative thereto and to each other. A range of inventive solutions that have been developed to address some or all of these design challenges. | 08-16-2012 |
20130021715 | SYSTEM AND METHOD FOR IN-SITU CONDITIONING OF EMITTER ELECTRODE WITH SILVER - Cleaning and/or conditioning electrode surfaces can provide significant performance and operational benefits in EHD devices. In particular, conditioning of emitter electrode surfaces with silver (Ag), silver compositions or silver preparations applied in situ at successive times throughout the operating lifetime of an EHD air mover has been found to significantly reduce ozone production. Structures and techniques are described for in situ conditioning electrode surfaces and, in particular, emitter electrode surfaces of an EHD device such as an air mover or precipitator, with a conditioning material that includes silver. | 01-24-2013 |
20130340981 | ELECTROHYDRODYNAMIC (EHD) AIR MOVER CONFIGURATION WITH FLOW PATH EXPANSION AND/OR SPREADING FOR IMPROVED OZONE CATALYSIS - Provision of an expansion region (e.g., a flow path with increasing cross-section downstream of the EHD air mover) can provide operational benefits in EHD air mover-based thermal management systems. In contrast, such a design would generally be disfavored for conventional mechanical air mover-based systems. In some cases, an expansion chamber or volume may be provided between the EHD air mover and heat transfer surfaces. In some cases, expansion of the flow cross-section may be provided (at least in part) within the heat transfer surface volume itself. In some cases, leading surfaces of heat transfer surface (e.g., heat sink fins) may be shaped, disposed or otherwise presented to EHD motivated flow to reduce “laminarity” of the impinging air flow so as to reduce thermal transfer boundary layer effects and/or to divert flow outward in the flow channel so as to more evenly distribute ozone molecules over catalytic sites. | 12-26-2013 |
20140003964 | ELECTROHYDRODYNAMIC (EHD) FLUID MOVER WITH FIELD BLUNTING STRUCTURES IN FLOW CHANNEL FOR SPATIALLY SELECTIVE SUPPRESSION OF ION GENERATION | 01-02-2014 |
20140097722 | ELECTROHYDRODYNAMIC (EHD) FLUID MOVER WITH COLLECTOR ELECTRODE LEADING SURFACE SHAPING FOR SPATIALLY SELECTIVE FIELD REDUCTION - In various electrohydrodynamic (EHD) fluid mover designs disclosed herein, electric field strength may be locally reduced in peripheral regions of an emitter-to-collector electrode gap. As a result, detrimental accumulations of silica, dust and other airborne contaminants can be reduced on surfaces in such peripheral regions, which may otherwise be susceptible to accumulations and/or difficult to clean or condition. In some cases, localized reduction in electric field near sidewall surfaces can provide desirable localized reductions in susceptibility to contaminant related spark or shunting current paths. In some cases, such as when a field blunting structure is employed and (as a result) a generally more uniform electric field pattern is provided locally, an engineered or purposeful local reduction both electric field strength and ion generation in peripheral regions of an emitter-to-collector electrode gap may be quite desirable. | 04-10-2014 |
20140271239 | SPARK SUPPRESSION BALLAST CLOSELY COUPLED TO EMITTER ELECTRODE OF ION GENERATOR - By directly connecting, ballast to an emitter electrode of an ion generator (e.g., a corona-discharge device), a rapid and self-corrective reduction in emitter-to-collector voltage may be provided responsive to an increase in current characteristic of incipient sparking discharge. Voltage levels in the emitter-to-collector gap can be rapidly reduced based on voltage drop across the ballast that, while negligible under nominal ion current conditions, transiently increases in the event of a sparking discharge. As a result, the portion of supply voltage (typically multi-KV supply voltage) across the emitter-to-collector gap is transiently reduced to levels below a current breakdown voltage and, indeed, field intensity proximate to the emitter is transiently reduced below levels otherwise necessary to sustain ion generation. | 09-18-2014 |
Patent application number | Description | Published |
20100052540 | ELECTROHYDRODYNAMIC FLUID ACCELERATOR DEVICE WITH COLLECTOR ELECTRODE EXHIBITING CURVED LEADING EDGE PROFILE - Performance of an electrohydrodynamic fluid accelerator device may be improved and adverse events such as sparking or arcing may be reduced based, amongst other things, on electrode geometries and/or positional interrelationships of the electrodes. For example, in a class of EHD devices that employ a longitudinally elongated corona discharge electrode (often, but not necessarily, a wire), a plurality of generally planar, collector electrodes may be positioned so as to present respective leading surfaces toward the corona discharge electrode. The generally planar collector electrodes may be oriented so that their major surfaces are generally orthogonal to the longitudinal extent of the corona discharge electrode. In such EHD devices, a high intensity electric field can be established in the “gap” between the corona discharge electrode and leading surfaces of the collector electrodes. | 03-04-2010 |
20100116460 | SPATIALLY DISTRIBUTED VENTILATION BOUNDARY USING ELECTROHYDRODYNAMIC FLUID ACCELERATORS - In thermal management systems that employ EHD devices to motivate flow of air through an enclosure, spatial distribution of a ventilation boundary may facilitate reductions in flow resistance by reducing average transit distance for cooling air from an inlet portion of the ventilation boundary to an outlet portion. Some thermal management systems described herein distribute a ventilation boundary over opposing surfaces, adjacent surfaces or even a single surface of an enclosure while providing a short, “U” shaped, “L” shaped or generally straight through flow path. In some cases, spatial distributions of the ventilation boundary facilitate or enable enclosure geometries for which conventional fan or blower ventilation would be impractical. In some cases, provision of multiple portions of the ventilation boundary may allow the thermal management system to tolerate blockage or occlusion of a subset of the inlet and/or outlet portions and, when at least some of such portions are non-contiguous spatially-distributed, tolerance to a single cause of blockage or occlusion is enhanced. | 05-13-2010 |
20100116464 | REVERSIBLE FLOW ELECTROHYDRODYNAMIC FLUID ACCELERATOR - Reversible flow may be provided in certain EHD device configurations that selectively energize corona discharge electrodes arranged to motivate flows in generally opposing directions. In some embodiments, a first set of one or more corona discharge electrodes is positioned, relative to a first array of collector electrode surfaces, to when energized, motivate flow in a first direction, while second set of one or more corona discharge electrodes is positioned, relative to a second array of collector electrode surfaces, to when energized, motivate flow in a second direction that opposes the first. In some embodiments, the first and second arrays of collector electrode surfaces are opposing surfaces of individual collector electrodes. In some embodiments, the first and second arrays of collector electrode surfaces are opposing surfaces of respective collector electrodes. | 05-13-2010 |
20100116469 | ELECTROHYDRODYNAMIC FLUID ACCELERATOR WITH HEAT TRANSFER SURFACES OPERABLE AS COLLECTOR ELECTRODE - In thermal management systems that employ EHD devices to motivate flow of air between ventilated boundary portions of an enclosure, it can be desirable to have some heat transfer surfaces participate in electrohydrodynamic acceleration of fluid flow while providing additional heat transfer surfaces that may not. In some embodiments, both collector electrodes and additional heat transfer surfaces are thermally coupled into a heat transfer path. Collector electrodes then contribute both to flow of cooling air and to heat transfer to the air flow so motivated. The collector electrodes and additional heat transfer surfaces may be parts of a unitary, or thermally coupled, structure that is introduced into a flow path at multiple positions therealong. In some embodiments, the collector electrodes and additional heat transfer surfaces may be proximate each other along the flow path. In some embodiments, the collector electrodes and additional heat transfer surfaces may be separate structures. | 05-13-2010 |
20100155025 | COLLECTOR ELECTRODES AND ION COLLECTING SURFACES FOR ELECTROHYDRODYNAMIC FLUID ACCELERATORS - Embodiments of electrohydrodynamic (EHD) fluid accelerator devices utilize collector electrode structures that promote efficient fluid flow and reduce the probability of arcing by managing the strength of the electric field produced at the forward edges of the collector electrodes. In one application, the EHD devices dissipate heat generated by a thermal source in a thermal management system. | 06-24-2010 |
20110149252 | Electrohydrodynamic Air Mover Performance - Structures for reducing the effect of charged surfaces near the electrodes on the performance efficiency of an electrohydrodynamic (EHD) device are disclosed. The potential levels on surfaces of an electronic device near the EHD electrodes are varied with respect to a function of the combination of distance from the emitter and the distance from the collector. The potential levels may be constant, may vary in discrete steps, may be continuously variable along the length between the EHD electrodes and beyond the electrodes, and may vary with respect to time. | 06-23-2011 |
20110292560 | ELECTROHYDRODYNAMIC FLUID MOVER TECHNIQUES FOR THIN, LOW-PROFILE OR HIGH-ASPECT-RATIO ELECTRONIC DEVICES - Surfaces for electromagnetic shielding, retaining electrostatic charge and indeed collecting ion current in EHD fluid mover designs may be formed as or on surfaces of other components and/or structures in an electronic device. In this way, dimensions may be reduced and packing densities increased. In some cases, electrostatically operative portions of an EHD fluid mover are formed as or on surfaces of an enclosure, an EMI shield, a circuit board and/or a heat pipe or spreader. Depending on the role of these electrostatically operative portions, dielectric, resistive and/or ozone robust or catalytic coatings or conditioning may be applied. | 12-01-2011 |
20120121487 | ELECTRONIC SYSTEM WITH VENTILATION PATH THROUGH INLET-POSITIONED EHD AIR MOVER, OVER OZONE REDUCING SURFACES, AND OUT THROUGH OUTLET-POSITIONED HEAT EXCHANGER - An electronic system enclosure houses a plurality of electronic components together presenting one or more surfaces coated with ozone reducing material. An EHD air mover positioned remote from an outlet ventilation boundary of the enclosure motivates air flow through the enclosure along a flow path past the one or more surfaces coated with ozone destructive material over heat transfer surfaces and out through an outlet ventilation boundary of the enclosure. | 05-17-2012 |
20120314334 | EHD DEVICE IN-SITU AIRFLOW - An electrohydrodynamic (EHD) air mover is positionable within the enclosure to, when energized, motivate air flow through the enclosure along a flow path between the inlet and outlet ventilation boundaries. Ductwork within the enclosure has cross-sections substantially matched to a cross-section of the EHD air mover. A fan curve-type, pressure-air flow characteristic measured for the EHD air mover in open air substantially overstates mechanical impedance of the EHD air mover to air flow along the flow path between the inlet and outlet ventilation boundaries in that, when the EHD air mover is operably positioned within the enclosure appurtenant to the ductwork, no more than about 50% of the mechanical impedance of the EHD air mover indicated by the measured fan curve-type, pressure-air flow characteristic actually contributes to total mechanical impedance to air flow through the enclosure along the flow path between the inlet and outlet ventilation boundaries. | 12-13-2012 |