Showing papers on "Contactor published in 1992"

Systems analysis of electrodynamic tethers

Abstract: A dynamic simulation model is developed and employed in a new system study to investigate the performance of electrodynamic tethers, both as power generators and thrusters. The electron collection performance of a contactor and a bare wire tether, both separately and in combination, are compared and contrasted. The power and thrust generated by a bare wire tether is found to have a higher dependence on the geomagnetic and ionospheric fluctuations. However, depending on the performance of the contactor, the combination of a bare tether and contactor can substantially boost performance for power generation. As a pure thruster, the contactor tether is examined at constant current, voltage, thrust, and power. It is found that the best mode of operation is with constant power, with resulting power/thrust ratios better than those for ion or magnetoplasmadynamic engines. It is concluded that tethers offer greater potential than previously envisioned.

Liquid-liquid contactor

Abstract: In a non-agitational, countercurrent flow type of liquid-liquid contacting tower, splitter plates with plural slits and/or holes through which light and heavy liquids flow, and baffles having the appropriate shapes and areas in order to cover the liquid flowing upward or downward, are alternately mounted horizontally inside the tower shell in vertical direction. The ratios of the opening area to the total cross-sectional area in the splitter plate are 10% to 40%, and the opening area of a baffles is larger than the aperture area of a splitter plate. The advantages of this invention are as follows: Because of the high contacting efficiency, a relatively smaller contactor has an equivalent performance with that of a larger contactor; there exists no risk of plugging due to scum accumulation, and maintenance is easy.

Inverter controlled air conditioner capable of effectively reducing a rush current at starting

Abstract: This invention provides an inverter controlled air conditioner capable of employing a rush current preventing relay having a small capacitance, thereby decreasing the cost. An inverter circuit includes a rectifying circuit connected to an AC power supply, a smoothing capacitor connected to the output terminals of the rectifying circuit, and a switching circuit, connected to the two terminals of the capacitor, for outputting a voltage having a predetermined frequency upon performing switching. An auxiliary power supply circuit has a rectifying circuit connected to the AC power supply. A control section drives the switching circuit with an output from the rectifying circuit as the operation voltage. Relay drive circuits for receiving the output from the rectifying circuit as the operation voltage are connected to an electromagnetic contactor and a relay. When the air conditioner is started, the control section energizes the relay for a predetermined period of time t s through the relay drive circuits and thereafter energizes the electromagnetic contactor. Normally-open contacts of the electromagnetic contactor are connected between the AC power supply and the inverter circuit. The capacitor of the inverter circuit is connected to the output terminals of the rectifying circuit of the auxiliary power supply circuit through a resistor and normally-open contacts of the relay.

Microprocessor based electrical contactor with distributed contactor opening

Abstract: A multiphase contactor with solid state circuity gating rectified pulses to an electromagnetic coil to close and hold closed contacts for each phase, sequentially for each successive opening of the contactor adjusts the delay angle of the last pulse to rotate the sequence in which the individual phase currents are interrupted. By alternately making the last pulse positive or negative the polarity of the interrupted current alternates to further promote even contact wear.

Contactor for electric part

Abstract: A contactor for an electric part comprising a plurality of pressure bearing elements connected at one ends thereof and extending in opposed relation with each other, the other ends thereof being left as free ends, a movable contactor having a press contacting portion being formed at the connection end of the pressure bearing elements, the press contacting portion being pushed up by elastic force stored by the pressure bearing elements which are closed or opened against elasticity thereof, thereby obtaining a contacting pressure with a contact of an electric part.

Wastewater treatment apparatus

Abstract: Disclosed herein is a wastewater treatment facility comprising a structure defining first and second tank portions; a shaft rotatably supported by the structure; a first biological reactor in the first tank portion and including a first rotatable biological contactor mounted to the shaft and having a diameter; and a second biological reactor in the second tank portion and including a second rotatable biological contactor mounted to the shaft and having a diameter greater than the diameter of the first rotating biological contactor.

Remote control method and device for engine welding machine

Abstract: PURPOSE:To facilitate the control of a current controller by a coded high-frequency signal for remote control by bringing the output end of a welding cable superposed with the high frequency for remote control into contact with base metals for welding by as much as a set number of times via a noise filter. CONSTITUTION:The contactor of a holder 29 or the 1st contact terminal of a touch sensor A is first brought into contact with the base material 31 by the set number of times as to the engine start in the case of changing over of a changing over circuit 20 for one person and two persons to one person. The high-frequency signal for remote control outputted from a high-frequency oscillator 39 by this contact flows from the welding cable 33a as if the signal flows to a holder 20, the noise filter 44, the base metal 31 and the welding cable 33b. This signal is detected by a current transformer CT1 for signal detection and is inputted via a 1st amplifier 41 and an amplifier 43 for low level to a CPU. The prescribed processing operation is executed in the CPU.

Treatment of water

Abstract: Oxygen is separated from air by pressure swing adsorption in plant 2. The oxygen is passed through an ozone generator 4. The resulting ozonated oxygen is passed upwardly through a contactor 6 countercurrently to the flow of a side stream of water to be treated with ozone. The side stream containing dissolved ozone flows from the contactor 6 to a mixer 8 in which it is mixed with a main stream of water. The effluent gas from the contactor 6 contains air displaced from the water and undissolved oxygen. It is divided into two parts. One part flows to the pressure swing adsorption plant 2 and is separated therein with the air. The other part is dried by temperature swing adsorption in drier 20 and the resulting dried gas is ozonated in the ozone generator 4 with the oxygen from the plant 2.

Aquaculture water treatment system including combined rotating biological contactor and evaporative cooler

Abstract: The present invention is directed to a closed cycle aquaculture system for fish rearing which includes as part of a water treatment subsystem a rotating biological contactor. The contactor nitrifies the contaminated water to remove toxic materials therefrom and also can be operated to maintain the temperature of the water near the wet-bulb temperature of the surrounding air when desirable.

A model for dynamic analysis of AC contactor

Abstract: A methodology for dynamic analysis of AC contactors is presented. In these devices, mechanical and electrical parts are coupled and it is necessary to evaluate with good precision the electrical parameters, especially the inductances. The device is voltage fed through a sinusoidal source; the dynamic force equation is considered; and a method for numerical integration is adopted. A finite element method is used to determine the parameters used in an equivalent circuit. The comparison between theoretical and experimental results shows that the methodology is consistent. >

Color cathode ray tube having improved spring type contactor

Abstract: A color cathode ray tube is taught having an improved spring type contactor. The spring type contactor effects electrical connection between a frame and a conductive coating deposited on the inner surface of the funnel, and comprises an ' OMEGA ' shaped fitting portion for being inserted into holes respectively perforated on the shield and the frame to be locked therein, a pair of legs abutting the edge of the hole of the shield, and a 'C' shaped contact portion extended from one of the legs to contact with the conductive coating on the inner surface of the funnel. According to the present invention, the inner magnetic shield is conveniently affixed to the frame, and the electrical resistance between the frame and the conductive coating is diminished so remarkably that the residual electrons in the cathodoluminescent screen and the shadow mask can effectively by-pass to the conductive coating.

Acid recycling system

Abstract: A system for removing acid from a metal-rich acid stream by diffusion dialysis. The acid stream is contacted with a water stream through an ion exchange membrane, in a series, counter-current flow contactor. The contactor is formed of a stack of layers of ion exchange membranes and impervious separators with flow-control apertures. The stack includes switch-back spacers which cause the flow to switch direction.

Electromagnetic contactor with closure fault indicator

Abstract: An electromagnetic contactor assembly with a sensing circuit for determining contactor state based upon the reluctance of the contactor coil. The coil has an electromagnetic coil and a movable contact separated from the coil by a gap when the coil is not energized. Energizing the coil causes the movable contact to close the gap and contact the coil. The determination of the relationship between the reluctance in the coil when the gap is in an open and closed state allows contactor gap status to be measured by measuring the coil inductance. A sensing circuit is added to the drive circuit to measure changes in AC current during the pulse cycle which holds the contacts in this closed position. The sensing circuit measures the AC current and is able to signal contactor status based on that value.

Continuous fluidized-bed contactor with recycle of sorbent

Abstract: A continuous fluidized-bed contactor containing sorbent particles is used to remove solutes from liquid solvents. As the sorbent particles, for example gel beads, sorb the solute, for example metal ion species, the sorbent particles tend to decrease in diameter. These smaller loaded sorbent particles rise to the top of the contactor, as larger sorbent particles remain at the bottom of the contactor as a result of normal hydraulic forces. The smaller loaded sorbent particles are then recovered, regenerated, and reintroduced into the contactor. Alternatively, the loaded sorbent particles may also slightly increase in diameter, or exhibit no change in diameter but an increase in density. As a result of normal hydraulic forces the larger loaded sorbent particles fall to the bottom of the contactor. The larger loaded sorbent particles are then recovered, regenerated, and reintroduced into the contactor.

Theory of Plasma Contactor Neutral Gas Emissions for Electrodynamic Tethers

Abstract: An existing anisotropic anodic plasma contactor model is extended to include neutral gas emissions. Within the framework of the contactor model, the inclusion of external ionization leads to an integro-differential equation. By choosing the ratio of the contactor radius (ao) to the neutral gas-electron ionization mean free path at the contactor exit (Awo) as a suitable expansion parameter, an analytical expression for the current-voltage characteristic can be found for (ao/X^o) < 1, which corresponds to weak external ionization. The performance of this contactor model is examined via a dynamic simulation model developed for electrodynamic tethers. Detailed models of the geomagnetic field and the ionosphere are used to create a realistic environment. The highly nonlinear contactor voltage-current characteristic is incorporated into a circuit equation, which includes radiation impedance, and is solved along the tether's orbit. Results show that it is more effective to fully ionize the contactor gas internally than to partially ionize it externally and that, based on the specific power for the tether system, the optimum gas to use is argon. In addition, the effect of the radiation impedance on tether system performance is examined.

Secondary sensing system for contactor control system

Abstract: In an animal confinement structure having a contactor control device which controls a temperature control apparatus utilized for applying heating or cooling to the structure responsive to the ambient temperature sensed, a secondary system employed for control of temperature outside a preselected temperature regime, upon the failure of the contactor control device or loss of power. A remote temperature sensor is operatively connected to a pair of electronic thermostatic circuits for independently sensing the ambient temperature for comparison to the preselected range, and connected to a power supply utilized for energizing a relay resulting in the temperature control apparatus by independently actuated responsive to the sensed ambient temperature. The secondary system may be selectively used to control a temperature control apparatus which provides either heating or cooling.

Variable transformer with slidable contactor

Abstract: A voltage control system has a pair of clockwise and counterclockwise interleaved coils on a portion of a transformer core, the coils having multiple spaced turns providing sets of co-planar alternate electrical contact pairs extending linearly to form a tapping system for varying the output voltage of the transformer. A conductive electrical bridging member is movable in the linear direction of extension of the contacts and bridges a selected pair of contacts, one contact from each coil, to alter the effective number of electrical turns of the two coils between a minimum and maximum output voltage. An adjunctive feature is to provide both a contact lead to the bridging member and appropriate rectification at output ends of the pair of coils in order to produce a direct current output.

Treatment of water with ozone

Abstract: Oxygen is separated from air by pressure swing adsorption in plant 2. The oxygen is passed through an ozone generator 4. The resulting ozonated oxygen is passed upwardly through a contactor 6 countercurrently to the flow of a side stream of water to be treated with ozone. The side stream containing dissolved ozone flows from the contactor 6 to a mixer 8 in which it is mixed with a main stream of water. The effluent gas from the contactor 6 contains air displaced from the water and undissolved oxygen. It is divided into two parts. One part flows to the pressure swing adsorption plant 2 and is separated therein with the air. The other part is dried by temperature swing adsorption in drier 20 and the resulting dried gas is ozonated in the ozone generator 4 with the oxygen from the plant 2.

Coil current regulator with induced flux compensation in an electromagnetic contactor system

Abstract: The coil holding current of a contactor is regulated to the lesser of two measurements of coil current during each cycle of the full-wave rectified control voltage to compensate for induced flux in the coil generated by load current through the main contacts of the contactor, thereby preventing uncontrolled drop out of the contactor.

Auxiliary power supply for vehicle

Abstract: PURPOSE:To realize quick restart after power interruption due to overvoltage by a constitution wherein a power supply interrupting means opens a disconnector when a voltage detector detects terminal voltage of a filter capacitor higher than a predetermined level thus discharging the filter capacitor through a resistor and then a power supply restarting means throws in the disconnector, CONSTITUTION:When an overvoltage detector 7 detects a voltage higher than a set level, an OFF signal is fed to a GTO thyristor 5 thus closing the contact 13a of an overvoltage detector 13. Since b contact 16b of a relay opens, discharging takes place gradually through a resistor 18 and a capacitor 19 and the exciting coil 10c of a discharge contactor 10A is deenergized slowly thus closing the discharge contactor 10A after opening of a disconnector 2A. Consequently, a filter capacitor 4 is discharged through a charging resistor 9, a filter reactor 3, the discharge contactor 10A and a discharge resistor 11. After the exciting coil 16c of a relay is deenergized, the b contact 16b of the realy closes to restart the auxiliary power supply for vehicle automatically.

Method of making a variable power resistor

Abstract: A variable power resistor includes a heat sink having a front face and a back face with an electrically insulating, thermally conductive ceramic coating bonded directly onto the front face such that the ceramic coating is in direct thermal contact with the heat sink. A plurality of discrete thick film conductive circuit pads are positioned on the electrically insulating, thermally conductive ceramic coating and a thick film resistive layer is positioned over portions of the conductive circuit pads such that the pads are electrically connected in series. The variable power resistor also includes a moveable contactor capable of contacting the circuit pads in order to vary the resistance of the resistor and an electrical connection between the resistor and an electrical circuit. The electrically insulating, thermally conductive ceramic coating may be plasma sprayed onto the heat sink, while the resistive circuit may be screen printed onto the ceramic coating.

Ground fault detection controller

Abstract: PURPOSE: To detect a ground fault by connecting in series a rush current limiting resistor and power relays connected to both ends of the resistor to a smoothing capacitor connected in parallel with voltage subjected to full-wave rectification. CONSTITUTION: When a three-phase power source 1 is input, a control power supply part 11 operates. A comparison determining part 16 instructs that a contactor 20 whose contact is connected to a single-phase contactor 17 in parallel is turned ON before the contactor 17 is turned ON. If a ground fault exists at this time, grounded current flows, but the grounded current is limited by rush and grounding limiting resistor 5. The grounded current charges a smoothing capacitor 6 and voltage between terminals of the capacitor 6 rises, so that a ground fault can be detected by a voltage detecting part 12. If the capacitor 6 is not charged, no existence of the ground fault is determined. Further, since the rush grounding limiting resistor 5 can be set at a relatively large ground, the grounded current of a detected ground can be reduced. COPYRIGHT: (C)1993,JPO&Japio

Switching demonstration teaching aid

Abstract: The utility model relates to a teaching aid for exercising back break operation and fault reclosing. The utility model is provided with a programmable controller whose output end is provided with an AC contactor and whose input end is provided with a universal switch, a reclosing locking and reset switch circuit and a simulation switch circuit for protection actions. The utility model can be used for any fault simulation operation exercises of closing trip, reclosing return throw of a circuit breaker, and can also be directly used for the control operation of a high-voltage circuit breaker in production, having obvious effect on improving the reclosing success ratio.

Impact contactor particularly for projectiles with an explosive charge

Abstract: The contactor for firing a pyrotechnique charge comprises a support base (6) made of an insulating material and having at least two conducting terminals (7 and 8), a contact sleeve (13) centered coaxially on the base and in contact with one of the terminals, having pins which can be centrifugally displaced by elastic element (22), a deformable, conductive case (24) in contact with the second terminal, and a conductive slide-bar (28) which can move under inertia on the axis of symmetry against the effect of a retaining spring (31). Application as impact contactor for projectiles.

Circuit breaker with parallel resistor

Abstract: A circuit breaker with a parallel resistor which fulfills with a simple structure incompatible requirements for a resistance circuit making contact with regard to maintenance of the dielectric strength and prearcing characteristic between electrodes. A resistance circuit making contact 2 and a resistance circuit breaking contact 3 are electrically connected in parallel, one end of the parallel circuit is connected to one end of a common resistor and the other end of the parallel circuit and the other end of the resistor are connected to the respective ends of a main contact 1. After the opening of the resistance circuit making contact 2 the resistance circuit breaking contact 3 is still closed.

Temperature measuring device

Abstract: PURPOSE:To accurately measure a temperature in a package without influence of a contact resistance between a lead terminal of an IC package and a contactor or a current leakage by measuring the temperature in the package by using a temperature sensor sealed in the package. CONSTITUTION:A temperature detector 10, a converter 14 for converting a temperature detection output into a digital measured value, a correction value memory for storing a correction value for the output of the converter 14, and a calculator 16 for correcting the measured value based on the correction value and introducing it out of the package, are provided. A power source intermittent controller 3b for intermittently supplying power by an external command is provided on a semiconductor chip, and a temperature rise is eliminated by a measured power as much as possible.

Exciting circuit of voltage doubler common use electromagnet and electromagnetic contactor

Abstract: PURPOSE:To decrease the amount of supplied power at the holding time of a movable iron, core, and restrain the total equipment size from being large, by selectively supplying a half-wave rectified current and a full-wave rectified current to a main exciting coil and a sub-exciting coil by a current rectifying circuit, at the time when a 100% voltage is applied and the time when a 200% voltage is applied, respectively. CONSTITUTION:When a 200% voltage, e.g. a voltage of 200 V is applied across a common terminal COM and a 200% voltage terminal V2 by the switching of a voltage selection circuit part, a current passes through a half-wave rectifier D3 and turns to a half-wave rectified current I1. Said current flows into a exciting coil M1, which is excited and pulls in a movable iron core. Then the magnetic flux of the movable iron core increases, but a current I2-1 in the direction to block the magnetic flux is induced in a sub-exciting coil M2, because a change-over switch S is closed. Said current I2-1 flows through the following; the sub-exciting coil M2, a normally-closed contact S1, the change-over switch S, and the sub-exiting coil M2. Hence the magnetic flux in the movable iron core is decreased, and the attraction to the movable iron core is decreased.

Relays and contactors with low power consumption

Abstract: The invention relates to a relay and contactor with magnetic or mechanical holding-up for low power consumption. When in operation, it is monitored by a control circuit and in case of power failure it is automatically released from operating state.

Practical Design Of A New Ozone Contactor: The Deep U-Tube

Abstract: This paper presents a practical design of a new ozone contactor (the deep U tube). It is a based on the modeling of upward and downward bubbly flow of air and water, derived from a balanced equation of continuity and momentum. Two hydrodynamic parameters are estimated: the void fraction and the frictional pressure drop. Experimental data carried out on full-scale plant and pilot plant are compared to theoretical results predicted by the model. Flow of the liquid phase is performed from tracer tests in order to determine the detention time which is introduced into the CT concept for disinfection. The influence of flow model shows that a plug flow reactor is more efficient than a CSTR; the DUT is close to plug flow.