Abstract: In accordance with one embodiment, the present technique provides a circuit interrupter. The exemplary circuit interrupter includes conductive spanner that completes an electrical pathway between first and second electrical conductors. To facilitate a good electrical connection between the conductive spanner and the first and second conductors, the exemplary interrupter includes a biasing mechanism that biases the conductive spanner toward the first and second conductors. However, in the event of a fault condition, for instance, the conductive spanner is displaced away from the first and second conductors by magnetic forces, and the electrical path is interrupted. To facilitate this displacement, the biasing mechanism presents an opposing force to displacement relationship with a negative slope. That is to say, the biasing force provided by the biasing mechanism decreases as the distance between the conductive spanner and the first and second electrical conductors increases.

Abstract: A plurality of acoustic wave transducers are coupled to a substrate at predetermined spaced apart locations. At least one of the transducers is operative to emit an acoustic wave that propagates along the substrate, with the other transducers operating as receivers of acoustic waves. The receivers are coupled to a control system that is operative to determine a location at which the substrate is perturbed based on time associated with travel of an acoustic wave from a transmitter, to the location of the perturbation, and from the perturbation to each of the respective receivers.

Abstract: A plurality of acoustic wave transducers are coupled to a substrate at predetermined spaced apart locations. At least one of the transducers is operative to emit an acoustic wave that propagates along the substrate, with the other transducers operating as receivers of acoustic waves. The receivers are coupled to a control system that is operative to determine a location at which the substrate is perturbed based on time associated with travel of an acoustic wave from a transmitter, to the location of the perturbation, and from the perturbation to each of the respective receivers.

Abstract: A plurality of acoustic wave transducers are coupled to a substrate at predetermined spaced apart locations. At least one of the transducers is operative to emit an acoustic wave that propagates along the substrate, with the other transducers operating as receivers of acoustic waves. The receivers are coupled to a control system that is operative to determine a location at which the substrate is perturbed based on time associated with travel of an acoustic wave from a transmitter, to the location of the perturbation, and from the perturbation to each of the respective receivers.

Abstract: A method for interrupting current is provided wherein substantially all current is conveyed through a normal current carrying path in a circuit interrupter. A movable element is displaced for interruption of the current, and a balance is struck between the normal current carrying path and a parallel alternative or transient current carrying path. The transient current carrying path includes at least one variable or controllable resistance element. The transient current carrying path presents a substantially open circuit during normal operation. The variable resistance elements have a lower resistance during initial phases of circuit interruption, favoring transition of all current from the normal current carrying path to the transient path. Thereafter, the variable resistance elements increase in resistivity, producing additional back-EMF to drive the fault current to a zero level and to limit let-through energy.

Abstract: A technique is provided for enhancing performance of a circuit interrupter by deionizing arc plasma developed during an interruption event. A source material is disposed in a secondary current carrying path parallel to a primary current carrying path through the device. Upon movement of a movable contact in the primary current carrying path, current begins to flow through the source material, causing surface ablation of a material which deionizes arc plasma, resulting in greater voltage investment in the arc and more rapid extinction.

Abstract: An electrical circuit interrupter includes a primary or normal current carrying path and a transient or alternative current carrying path. The normal current carrying path is established by a movable spanner extending between stationary contacts during normal operation. The transient current carrying path includes at least one variable resistance element which transitions from a lower resistance to a higher resistance during interruption. The transient current carrying path forms an open circuit in parallel with the normal current carrying path during normal operation. Upon interruption, the transient current carrying path is favored for the fault current, completely interrupting the normal current carrying path. The variable resistance elements increase their resistivity during this phase of operation to aid in providing high levels of back-EMF for complete interruption of fault current through the device and limitation of let-through energy.

Abstract: A technique for reducing arc retrogression in a circuit interrupter includes providing a source material in a parallel current carrying path in the interrupter. The source material and parallel current carrying path support no current during normal operation. Upon interruption of a primary current carrying path, current flows through the source material, causing surface ablation of material which enhances the dielectric of the arc plasma, permitting more rapid entry of the arc into a dissipating structure such as a splitter plate stack. The source material transitions to a higher resistance level by heating to limit current flow during interruption.

Abstract: A technique is provided for forcing greater voltage investment in an arc developed during interruption of a current carrying path. A source element is provided in a secondary current carrying path parallel to a primary path through the device. Upon interruption of the primary current carrying path, an arc is forced to migrate towards a dissipating structure under the influence of an electromagnetic field. The source material then begins to carry current and undergoes surface ablation, releasing gas which is directed towards the migrating arc. The arc is thus caused to expand further, increasing voltage investment and resulting in more rapid extinction and reduction in let-through energy.

Abstract: An electrical circuit interrupter includes a primary or normal current carrying path and a transient or alternative current carrying path. The normal current carrying path is established by a movable spanner extending between stationary contacts during normal operation. The transient current carrying path includes at least one variable resistance element which transitions from a lower resistance to a higher resistance during interruption. The transient current carrying path forms an open circuit in parallel with the normal current carrying path during normal operation. Upon interruption, the transient current carrying path is favored for the fault current, completely interrupting the normal current carrying path. The variable resistance elements increase their resistivity during this phase of operation to aid in providing high levels of back-EMF for complete interruption of fault current through the device and limitation of let-through energy.

Abstract: A method for interrupting current is provided wherein substantially all current is conveyed through a normal current carrying path in a circuit interrupter. A movable element is displaced for interruption of the current, and a balance is struck between the normal current carrying path and a parallel alternative or transient current carrying path. The transient current carrying path includes at least one variable or controllable resistance element. The transient current carrying path presents a substantially open circuit during normal operation. The variable resistance elements have a lower resistance during initial phases of circuit interruption, favoring transition of all current from the normal current carrying path to the transient path. Thereafter, the variable resistance elements increase in resistivity, producing additional back-EMF to drive the fault current to a zero level and to limit let-through energy.

Abstract: A multiphase circuit interrupter includes a plurality of power phase sections for establishing and interrupting electrical power carrying paths for a plurality of phases Each power phase section includes first and second conductive regions which contact one another to complete the current carrying path for the phase. The second conductive region is movable to an interrupted position to interrupt the path. An interphase current carrying path is established between the power phase sections to conduct electrical energy between the sections following a trip event in any one of the sections. The interphase current carrying path may be established by a conductive element extending between the power phase sections. Channels may be formed in the interrupter housing between the power phase sections to communicate conductive plasma generated during separation of the contact regions from one another between the power phase sections.

Abstract: A multiphase circuit interrupter includes a plurality of power phase sections for establishing and interrupting electrical power carrying paths for a plurality of phases. Each power phase section includes first and second conductive regions which contact one another to complete the current carrying path for the phase. The second conductive region is movable to an interrupted position to interrupt the path. An interphase current carrying path is established between the power phase sections to conduct electrical energy between the sections following a trip event in any one of the sections. The interphase current carrying path may be established by a conductive element extending between the power phase sections. Channels may be formed in the interrupter housing between the power phase sections to communicate conductive plasma generated during separation of the contact regions from one another between the power phase sections.

Abstract: A circuit interrupter provides a conducting path between two conductors and interrupts the conducting path in response to overcurrent conditions in the conductors. The interrupter includes a magnetic core around which the conductors are disposed. Each conductor is electrically coupled to an arc runner and a spanner is biased into contact with the arc runners to compete a conducting path between the conductors. A secondary response mechanism is provided adjacent to the core and includes arms extending around the core and a magnetic body. In response to overcurrent conditions of a first magnitude the body of the secondary response mechanism is attracted to the core causing the arms to displace the spanner out of contact with the arc runners. In response to overcurrent conditions of a second magnitude, such as due to direct short circuits, the spanner is repelled rapidly to a non-conducting position and the secondary response mechanism is attracted to the core to hold the spanner in the non-conducting position.

Abstract: A method for interrupting electrical power between two conductors is provided, including biasing an electrically conductive element into a conducting position between two contact regions of the conductors. The contact regions are preferably portions of arc runners coupled to the conductors. The conductors surround a magnetic core that generates an electromagnetic field due to current in the conductors. The conductive element is repelled to a non-conducting position by the electromagnetic field in response to an overcurrent condition in the conductors. A secondary response mechanism is moved in response to the overcurrent condition to maintain the conductive element in the non-conducting position. For more gradually occurring overcurrent conditions, the secondary response mechanism is attracted toward the core, displacing the conductive element to the non-conducting position.

Abstract: A circuit interrupter provides a conducting path between two conductors and interrupts the conducting path in response to overcurrent conditions in the conductors. The interrupter includes a magnetic core around which the conductors are disposed. Each conductor is electrically coupled to an arc runner and a spanner is biased into contact with the arc runners to compete a conducting path between the conductors. A secondary response mechanism is provided adjacent to the core and includes arms extending around the core and a magnetic body. In response to overcurrent conditions of a first magnitude the body of the secondary response mechanism is attracted to the core causing the arms to displace the spanner out of contact with the arc runners. In response to overcurrent conditions of a second magnitude, such as due to direct short circuits, the spanner is repelled rapidly to a non-conducting position and the secondary response mechanism is attracted to the core to hold the spanner in the non-conducting position.

Abstract: Power is provided to a fluorescent lamp by connecting a source of alternating electrical current, consisting of a series of alternately positive and negative current pulses, to the lamp and shaping the current pulses such that the absolute value of the current increases as a function of time within each pulse.

Abstract: Electronically excited nitrogen fluoride, NF*, is generated by dissociating fluoride azide, FN.sub.3. In a preferred embodiment, the FN.sub.3 is reacted with vibrationally excited molecules such as hydrogen halide, deuterium halide, carbon dioxide, or nitrogen. In second and third embodiments, the FN.sub.3 is dissociated by laser pumping or by detonation. The NF* can provide a short wavelength laser by pumping the NF(b-X) transition in a resonant chamber or by the addition of an emitting species such as BiF to convert the stored energy of the NF* to photons from the emitting species.

Abstract: A gaseous mixture comprising iodine, oxygen and fluorine gases is circulated in a closed loop system 16 through a laser cavity 14. The gases in the cavity 14 are pumped by infrared laser radiation 12 from an iodine laser 10. A set of reactions occurs in the cavity 14 resulting in the production of excited, iodine monofluoride, molecules [IF**(B)] which emit laser radiation in the visible spectrum.

Abstract: A generating device for producing a laser energizing gas in the singlet delta, electronic state comprising a vacuum chamber; a tubular reaction chamber positioned within said vacuum chamber, said reaction chamber having a closed end and an oppositely disposed open end; means positioned in said closed end for introducing a flow of a gaseous reactant into said reaction chamber; means positioned adjacent said closed end at an angle perpendicular to the position of said gas introducing means for introducing a stream of a liquid reactant into said gas flow to effect a chemical reaction therebetween and the generation of a laser energizing, singlet delta gas; and means for interconnection to a lasing device for directing a flow of said generated, singlet delta gas to a lasing cavity.