Abstract: A system and method are provided for managing water coolant in a PEM fuel cell system's (10) coolant circuit (14). Gas-liquid separating apparatus (26) serves to efficiently transport liquid coolant containing gases, and to separate gases from the liquid coolant. The liquid coolant having the gases removed therefrom is then circulated through the liquid circuit by means of a conventional pump (24). A vacuum pump (28), such as a liquid eductor (28′), associated with the gas-liquid separating apparatus (26), serves to efficiently transport gas-phase and/or gas-liquid phase, fluids and to assist in the degasification of the liquid coolant. The eductor discharges to a separator/accumulator (30; 30′) which further facilitates separation of gases from liquid coolant.

Abstract: A titania-coated honeycomb catalyst matrix is provided for the ultraviolet-photocatalytic oxidation of organic pollutants in a flowing fluid. A honeycomb-shaped skeletal structure (12) has a thin, lightweight substrate (18) of metal or ceramic, typically an aluminum alloy, and a surface coating (20) of photocatalyst, such as titania. The photocatalyst (20) is bonded to the substrate (18) via a thin oxide layer (18′) on the substrate. The oxide layer (18′) may be grown on the substrate. The photocatalyst coating (20) is made by mixing (30) titania powder in a TiO2 sol-gel to form a titania slurry. The substrate with oxide layer is coated (30) with the titania slurry and then heat treated (31). The photocatalyst coating (20) is typically applied to substrate sheets (40, 60, 62) preformed for assembly into a honeycomb-shaped skeletal structure (12) having an array of parallel cells (46, 46′).

Abstract: A power system (8) is provided for economically supplying uninterrupted electrical power to one or more critical loads (14). One or more fuel cell power plants (18) provide one substantially continuous source of power, and a utility grid (10) provides another source of power. The fuel cell power plants (18) are adapted to be, and are, normally substantially continuously connected and providing power to, the critical load(s) (14). A rapidly-acting static switch (19) selectively connects and disconnects the grid power supply (10) to the critical load(s) (14) and with the fuel cell power plant(s) (18). A switch controller (49, 45) controls the state of the static switch (19) to connect the grid power source (10) with the critical load(s) (14) and the fuel cell power plant(s) (18) during normal operation of the grid (10), and to rapidly (less than 4 ms) disconnect the grid power source (10) from the load(s) (14) and fuel cell power plant(s) (18) when operation of the grid (10) deviates from normal beyond a limit.

Abstract: A shift converter (16) in a fuel processing subsystem (14, 16, 18) for a fuel cell (12) uses an improved catalyst composition (50) to reduce the amount of carbon monoxide in a process gas for the fuel cell (12). The catalyst composition (50) is a noble metal catalyst having a promoted support of mixed metal oxide, including at least both ceria and zirconia. Cerium is present in the range of 30 to 50 mole %, and zirconium is present in the range of 70 to 50 mole %. Additional metal oxides may also be present. Use of the catalyst composition (50) obviates the requirement for prior reducing of catalysts, and minimizes the need to protect the catalyst from oxygen during operation and/or shutdown.

Abstract: A fuel cell power plant system (10) having a membrane/electrode assembly (MEA) (21,22,23) fuel cell stack (11) is provided with the method and means for inerting the MEA through use of the coolant to effect a purge. Under normal on load operation, fuel flows through a fuel reactant flow path (30) at the anode side(s) of the stack (11), oxidant flows through an oxidant reactant flow path (29) at the cathode side(s) of the stack (11), and the coolant, typically water, flows through the coolant flow path (32,31) of the stack (11). However, during transient operations of shutdown and/or start-up, the coolant is at least temporarily redirected to one, or both, of the fuel and the oxidant reactant flow paths (30/29) in lieu of their respective supplies of fuel and oxidant. This serves to purge the respective reactant(s) from the respective flow path(s). To provide sufficient supply of coolant for the purge, the supply of coolant to the coolant flow path (32,31) may be reduced or terminated.

Abstract: A method and system are provided for controlling a fuel cell power plant (10). A demand signal (Mld) representing the anticipated current/power required by the electrical load(s) is provided. A current signal (Iap) representative of the actual current drawn by the load(s) (20) is provided. The greater of the demand signal (Mld) and the current signal (Iap) is selected (46) and utilized to provide a control signal (Mx, Mx′, Mx″) for regulating one or more of the reactants and coolant (24). One or more status signals (Xp, Xp′, Xp″, Vap) indicative of the status of a regulated one of more of the reactant/coolant and/or a respective operating process effected, is provided. Each status signal is transformed to a respective load capability signal (61, 61′, 61″). The lesser of the demand signal (Mld) and each of the load capability signals (61, 61′, 61 ″) is selected (62) to provide an output signal (Mi) for commensurately controlling a system load (20, 32).

Abstract: A fuel cell system (10) having a membrane/electrode assembly (MEA) (16) is provided with the means and technique for quickly inerting the MEA without requiring a nitrogen purge. A first fine pore plate (14) is positioned at an anode side of the MEA and defines a coolant flow field (36) and typically also, a fuel reactant flow field (48). A second fine pore plate (12) is positioned at a cathode side of the MEA and defines a lo coolant flow field (36) and typically also, an oxidant reactant flow field (38). A respective wettable substrate (22,26) is positioned between the MEA and each of the first and second fine pore plates, and is adjacent to the fine pore plates.

Abstract: A system is provided for the semi-active damping of oscillations during vertical motion of an elevator car relative to a desired trajectory along a relatively lengthy elevator travel path. The elevator car is connected to a motor-controlled support rope in a manner allowing limited relative vertical motion therebetween. A soft spring and a controllable damping means are connected in parallel between the rope and the elevator car. The damping means may be a hydraulic piston and cylinder arrangement controlled via a variable orifice valve. The spring may be a gas-pressurized accumulator connected to the hydraulics of the damping means. A control system provides a motion command signal to control the motor for motion control and the variable orifice valve for damping oscillations.

Abstract: A technique for providing a signal representative of blade vortex interaction (BVI) noise for a multi-blade rotorcraft. The fluid (air) pressure at one, two, or more predetermined locations on a rotor blade is measured during at least one predetermined azimuthal segment of blade rotation during operation to provide respective pressure measurements. The pressure measurements are processed to provide a signal for use as a control variable in a control system for the active control of BVI noise. The pressure measurements are made within 10% blade chord length of the blade leading edge and preferably two or more are made between 65% and 95% of blade radial-length. The pressure measurements are filtered and the band of retained frequencies is between 20 and 48 times the rotor rotation frequency. An algorithm operative over a determined blade frequency range optimizes the signal for control use.

Abstract: A virtually active hitch system is provided for the damping of vertical oscillations of an elevator car during a semi-active hitch mode of operation along a relatively lengthy elevator travel path and for load leveling the elevator car during an active mode when the elevator is braked. The virtually active hitch stores energy derived from the elevator motor during the semi-active mode, and utilizes that stored energy during the active mode to actively adjust the positioning of the elevator car, as might result from load changes. The hitch assembly may advantageously use hydraulic piston and cylinder means to adjust, or impede adjustment of, a limited hitch gap between a support rope and the elevator car. The hydraulic circuit associated with the piston and cylinder may include a variable orifice valve to control damping action and a pair of accumulators controlled via a switching network to selectively store and release energy and to also serve as a spring.

Abstract: A turbine engine inlet system includes a duct 14 to deliver air to the engine, inlet lips 16 and 52 to smooth the entry of air flowing into the duct, a screen 50 between the lips 52 and 16 for passage of inlet air, a forward inlet section 18 submerged within the aircraft skin contour to provide a degree of ram recovery to the duct, and a movable air deflector 20 which is positionable in a retracted position during normal flight, is extendable outward to a second position substantially flush with the screen 50 for maximum protection against foreign object damage (FOD), and is further extendable outward to a third position beyond the screen to provide an air bypass path when the screen is iced-over.

Abstract: A bistable electrical contactor employs a one-piece permanent magnet plunger operating in conjunction with an aligned pole piece and a pair of oppositely-wound coils to afford pulse-operated bistable operation of the associated contacts. The coils are wound in opposition to provide respective opposite electromagnetic fields, one "aiding" and one "opposing" the inherent magnetic flux of the plunger. The plunger may be spring-biased toward one of its two bistable positions, typically the one in which the plunger is most remote from the pole piece. When an appropriate coil is briefly energized, the respective "aiding" or "opposing" force is respectively added to or subtracted from the inherent magnetic force of the plunger to cause the appropriate change of state. The pole piece is structured and positioned to facilitate interaction with the plunger. An adjustable stop arrangement minimizes bounce of resiliently-mounted contacts.

Abstract: A bistable solenoid switch has a plunger and associated movable contact adapted for controlled reciprocation by a coil and bobbin assembly to either of two stable states not requiring sustained energization of the coil. The movable contact is biased toward one of the stable states, for example, "Contacts Closed" in which a pair of stationary contacts are engged by the movable contact. The bobbin is provided with one or more radial projections extending into its core for serving a detenting function with respect to a land formed on an end face of the plunger. When the bobbin projection is engaged by the plunger land, it is prevented from displacing the movable contact into engagement with the stationary contact, and the second, or "Contacts Open", state exists. Means are also provided for translating axial displacement of the plunger into angular displacement for moving it into and out of the detented engagement with the bobbin projection.

Abstract: A control system for a heating appliance, such as a microwave oven, includes a display and electronic circuitry for controlling operation of the appliance and the display. One of the control operations involves the timing of an interval, such as a cooking interval. Another such operation involves the selection of a power level. The display and a memory associated with the circuitry include predetermined dedicated time intervals and/or power level values depicted thereon and stored therein, respectively. Appropriate data-entry keys allow for the selection of these time and/or power values by slewing the display and thus the memory through the dedicated values. Separate keys may be provided for respectively incrementing and decrementing time and power.

Abstract: A display element mounting arrangement provides a pair of display holders for frictionally-engaging and supporting an elongated display element at its opposite ends. The display holders are adapted to be mounted on and frictionally secured to a support member, such as a circuit board. Each display holder includes a display-engaging portion and a support member-engaging portion. The display-engaging portion includes four walls which define a chamber into which an end of the display is inserted. Friction tabs in the chamber aid in retainedly engaging the display. The support member-engaging portion includes a leg adapted to extend through and move in a slot which extends inward from an edge of the circuit board. A foot formed on the end of the leg is so spaced from the display-engaging portion as to provide frictional engagement between it and the circuit board.

Abstract: An electrical equipment controller is provided with a delayed turn-off capability. A thermostat is in series with a control relay. The thermostat is further in parallel with the series combination of a relay latch contact and a first positive temperature coefficient (PTC) device. A second PTC device is connected in parallel with the control relay. The arrangement of first and second PTC devices provides a predeterminable drop-out relay including compensation for ambient temperature changes.

Abstract: An improved arrangement for retaining a terminal in a terminal holder includes providing a mounting opening through a wall of the terminal and provides a resilient snap-lock extending from the surface of a support member of the holder. The snap-lock extends through the terminal mounting opening for preventing relative longitudinal motion of the terminal in the holder and for yieldably restricting relative motion of the terminal substantially normal to the support member of the holder. The snap-lock has two locking fingers extending in "V"-shape fashion from the support member, which is preferably the holder's base. The locking fingers include camming surfaces to facilitate mounting the terminal on the locking fingers by moving the terminal transverse to its longitudinal extent. The holder is open at its top to facilitate mounting and removal of a terminal. A connector housing may be provided to removably close that opening.

Abstract: An electrical receptacle terminal having a longitudinal body for receiving a pin terminal includes a bifurcated beam spring forming two spring arms. The two spring arms act independently to urge an inserted pin terminal into good electrical contact with an opposing rib formed in an opposing wall. Each spring arm also includes a respective side flange which is contoured to engage the pin terminal in quadrature with the spring arms and rib. The pair of flanges have opposed faces for engaging opposite sides of the pin terminal. The spacing of the opposed faces of the flanges is normally less than the dimension of the pin terminal they engage such that they and the spring arms are resiliently spread by the pin terminal to thereby provide secure engagement. The four walls of the receptacle terminal are folded inward and rearward to form a continuous entry aperture and also to provide the spring arms.

Abstract: An electromagnetically operated fuel injection valve structured to include a housing having a fuel inlet opening, a fuel discharge opening and a fuel return opening, there being a continuous liquid path from the inlet opening to the return opening and an intermittent, or valved, liquid path from the inlet opening to the discharge opening. The continuous liquid path has a slope, in the direction of flow toward said return opening, which preferably is always 0 or positive relative to a horizontal axis or plane. A discharge valve is provided in the injector and exists in the valve path. The discharge valve is connected to an armature which is in turn actuated by a solenoid comprised of a coil, a tubular bobbin and an electromagnetic frame. The frame has a vertical tubular core portion and an upper flange extending outwardly therefrom. The coil is disposed on the bobbin and the bobbin is coaxially disposed about the frame core portion below the flange.