Nonconsumable Electrode (e.g., Atomic Hydrogen) Patents (Class 219/75)
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Patent number: 5008511Abstract: A plasma torch incorporated at plurality of arc forming chambers arranged symmetrically about an axis and each containing a first electrode. A common electrode cooperates with the electrode in each chamber to form an arc in each chamber and is provided with converging passages leading one from each chamber and converging into a common nozzle passage extending along the axis. A reactant feed passage opens into the common nozzle passage co-axial with the nozzle passage in a region of convergence of the converging passages to inject reactants into the center of the plasma jet formed in the nozzle passage in the direction of movement of the plasma jet through the nozzle passage.Type: GrantFiled: June 26, 1990Date of Patent: April 16, 1991Assignee: The University of British ColumbiaInventor: Douglas A. Ross
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Patent number: 5004153Abstract: A method for regulating the flow of liquid metal to an atomization zone is provided. The regulation is effected by imparting a high density flux to a stream of liquid metal as it descends toward the atomization zone. The high density flux is applied by a flux concentrator. The flux concentrator is a small sleeve-like element attached by parallel conductors to a larger sleeve-like element which acts as a secondary to primary coil extended through the larger sleeve element. By imparting high density flux to initiate a stream passing through the flux concentrator the cross sectional dimensions of the melt stream and the rate of flow of melt through the concentrator is regulated to values which are appropriate for a spray-form type of action.Type: GrantFiled: March 2, 1990Date of Patent: April 2, 1991Assignee: General Electric CompanyInventor: Thomas F. Sawyer
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Patent number: 5003150Abstract: Apparatus for inert gas shielded arc welding having a plenum with an outlet covered by a gas lens. An electrode provides electric current to the part being welded. The gas lens can overlie the lip of the plenum to prevent ambient air from being drawn into the gas envelope and contaminating the weld. The plenum can be teardrop shaped, having sidewalls which converge toward the trailing end. To enable the torch to weld a circumferential surface which is confined by an overhang, the inert gas is introduced near the leading edge of the plenum by a U-shaped conduit which circumvents the overhang. The plenum is much wider than it is deep and the flow of inert gas for shielding can be turned generally perpendicular to the direction of its introduction. Finally, the inert gas introduced into the plenum can be directed at an electrode post within the plenum, and the lip introducing the inert gas into the plenum can have a trailing edge which projects further into the plenum than does its leading edge.Type: GrantFiled: February 21, 1990Date of Patent: March 26, 1991Assignee: United Air Lines, Inc.Inventor: Gary A. Stricklen
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Patent number: 5003551Abstract: An apparatus and method for inductively melting a quantity of metal, without having to contain the metal in a crucible, is described. The solid metal to be melted is placed within a first induction coil excited by an alternating current and adapted to provide a greater electromagnetic force towards the lower portion of the quantity of metal. The solid metal rests on a support, having an opening therethrough, which also comprises means for keeping the support at a low temperature relative to the metal as it melts. When energy in the form of the alternating current is provided to the coil, the metal melts from the top downward, but the concentration of electro-magnetic force towards the bottom of the metal causes the liquid metal to retain a cylindrical shape. A non-varying electromagentic field is applied to the quantity of metal to minimize violent stirring of the molten portion of the quantity of metal caused by the time-varying field.Type: GrantFiled: May 22, 1990Date of Patent: March 26, 1991Assignee: Inductotherm Corp.Inventor: John H. Mortimer
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Patent number: 4990739Abstract: An improved plasma gun coaxially injects particles of ceramic materials having high melting temperatures into the central portion of a plasma jet. This results in a more uniform and higher temperature and velocity distribution of the sprayed particles. The position of the cathode is adjustable to facilitate optimization of the performance of the gun wherein grains of the ceramic material are melted at lower power input labels.Type: GrantFiled: July 7, 1989Date of Patent: February 5, 1991Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space AdministrationInventor: Isidor Zaplatynsky
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Patent number: 4979182Abstract: Two coils, between which a sample is kept in a contactless suspended state, are connected to separate power sources, at least one of which comprises a phase shifter. Both power sources are controlled by a common oscillation generator. If both currents in the coils are in phase, a magnetic dipole-field of high heating capacity is obtained. If the two currents in the coils are in counterphase, a quadrupole-field is obtained, which generates a high positioning force. By modifying the phase difference, it is possible to generate optional superpositions of the dipole-field and the quadrupole-field, whereby the parts of heating capacity and positioning capacity can be varied.Type: GrantFiled: September 18, 1989Date of Patent: December 18, 1990Assignee: Deutsche Forschungsanstalt fur Luft-und Raumfahrt eVInventor: Georg Lohoefer
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Patent number: 4977305Abstract: The invention is a method and apparatus that comprises supplying a mixture of gases to a constricted plasma arc. The mixture comprises a gas that will sustain the plasma arc at the lower voltages typical of electric-arc welding and in the absence of a plasma and a gas which provides good heat transfer characteristics. The relative proportion of the gas that will sustain the plasma arc at the lower voltages present in the mixture is large enough to support the plasma arc, and the relative proportion of gas having good heat transfer charactristics present in the mixture is small enough to prevent failure of the arc at the lower voltage. A voltage drop is maintained which is high enough to maintaing the plasma arc using the gas mixture while low enough to operate at a substantially constant current using a low voltage constant current power supply.Type: GrantFiled: April 3, 1989Date of Patent: December 11, 1990Assignee: L-Tec CompanyInventor: Wayne S. Severance, Jr.
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Patent number: 4973816Abstract: A plasma torch is provided with a safety switch which is connected in a circuit so as to control high voltage applied to the torch. The switch is held closed by the torch tip. When the tip is removed, as for service or replacement, the switch opens and disables the high voltage, so that personnel cannot accidentally be shocked.Type: GrantFiled: March 28, 1989Date of Patent: November 27, 1990Assignee: Delaware Capital Formation, Inc.Inventor: Randy G. Haberman
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Patent number: 4962291Abstract: An apparatus is disclosed for producing metal powder having a molten metal holding vessel with a generally cylindrical shaped bottom portion, a molten metal discharging runner located at the bottom portion of the holding vessel, a spraying chamber connected at a lower end of the discharging runner, a first induction heating coil having a diameter and surrounding the holding vessel, a second induction heating coil surrounding the discharging runner, and a ring-shaped magnetic shielding plate disposed between the second induction heating coil and the sliding gate. The discharging runner has a nozzle portion which includes a sliding gate made of ceramic. The sliding gate is movable for controlling the flow of the molten metal through the nozzle portion of the discharging runner. The spraying chamber has gas-jetting nozzles. The second induction heating coil has a diameter smaller than a diameter of the first induction heating coil.Type: GrantFiled: September 6, 1989Date of Patent: October 9, 1990Assignee: Daido Tokushuko Kabushiki KaishaInventors: Senji Fujita, Noboru Demukai
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Patent number: 4958057Abstract: A transfer-type plasma torch may be used to heat objects, for example, to heat molten steel at a certain stage of being supplied from a converter to a continuous casting mold. After a trigger electric discharge has been produced between the cathode and the ignition anode of the plasma torch, an electric discharge is effected between the cathode and an object to be treated that is set as the anode. The plasma torch includes a cylindrical cathode-holding member having therein a space allowing for the flow of coolant, an ignition anode disposed within the cathode-holding member, and a ring-shaped cathode disposed on an inner periphery of the cathode-holding member and positioned below the tip of the ignition anode, with the tip portion of the cathode projecting downwardly from the bottom face of the cathode-holding member. This arrangement eliminates a conventional nozzle, thereby allowing for a reduction in a diameter of the entire torch while enabling a relative increase in the diameter of the cathode.Type: GrantFiled: April 19, 1989Date of Patent: September 18, 1990Assignee: Nippon Steel CorporationInventors: Hiroshi Shiraishi, Nobuo Tajima, Tsuyoshi Shinoda, Nobuyoshi Hirotsu
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Patent number: 4954688Abstract: A plasma arc cutting torch is disclosed which includes a nozzle assembly below the electrode for injection of water around the plasma flow so as to constrict the arc. The nozzle assembly includes upper and lower disc like nozzle members which are spaced apart to define a water gap therebetween, and the members include aligned bores for permitting the plasma to flow therethrough to the underlying workpiece. The lower nozzle member is of extended length, and its forward or lower end portion is beveled to define a frusto-conical exterior surface, so as to permit the torch to be positioned closely adjacent the workpiece when making beveled cuts and so as to achieve the predetermined standoff which maximizes the quality and speed of the cut.Type: GrantFiled: November 1, 1989Date of Patent: September 4, 1990Assignee: ESAB Welding Products, Inc.Inventor: Duane N. Winterfeldt
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Patent number: 4942750Abstract: Apparatus and methods are disclosed for the rapid generation of high hydrostatic pressures and the concurrent delivery of said pressures to a workpiece. The apparatus and methods comprise the rapid thermal expansion and vaporization of a volatile fluid. The volatile fluid is typically liquid argon and heated typically by means of a controllable electric heater, delivered to the workpiece typically by means of a pressure-rupturable membrane. The disclosed apparatus and methods permit the application of high hydrostatic pressures to commercial-scale workpieces, in an economic manner and with reduced cycle times.Type: GrantFiled: January 23, 1989Date of Patent: July 24, 1990Assignee: Vital Force, Inc.Inventor: Robert M. Conaway
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Patent number: 4942281Abstract: A multi-torch interface allowing substantially immediate selection of one of a plurality of TIG welding torches. The interface may be retrofitted to an existing TIG welding system by attaching torch cables and inputs to the torches to a separate interface housing A series of valves and adapters within this housing are coupled to sources of current, inert gas, and coolant fluid and are actuated manually to allow for easy switching from one torch to another quickly and safely without tools. Alternatively, such an interface and series of valves, switches and adapters are incorporated within a TIG welding machine cabinet or power source and controlled by a ganged assemblage of switches and valves which are simultaneously actuated.Type: GrantFiled: August 3, 1989Date of Patent: July 17, 1990Inventor: Craig F. Srba
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Patent number: 4940877Abstract: A plasma arc cutting torch embodying an electrode having a swirl tube and a nozzle thereabout, a spring mechanism bearing on the swirl tube and nozzle being caused by them to complete a circuit, the circuit not becoming completed in the absence of one of or both the swirl tube and nozzle.Type: GrantFiled: September 15, 1989Date of Patent: July 10, 1990Assignee: Century Mfg. Co.Inventor: Daniel M. Broberg
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Patent number: 4924053Abstract: A welding torch for gas tungsten arc welding apparatus has a hollow tungsten electrode including a ceramic liner and forms the filler metal wire guide. The wire is fed through the tungsten electrode thereby reducing the size of the torch to eliminate clearance problems which exist with external wire guides. Since the wire is pre-heated from the tungsten more wire may be fed into the weld puddle, and the wire will not oxidize because it is always within the shielding gas.Type: GrantFiled: December 5, 1988Date of Patent: May 8, 1990Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space AdministrationInventors: Gene E. Morgan, Gerald E. Dyer
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Patent number: 4924059Abstract: A plasma gun apparatus with precision adjustment of arc voltage, includes a gun body with a bore therethrough, a nozzle anode in the bore, a cathode holder engaged in the bore with threads, and a cathode mounted on the cathode holder. A locking ring is engaged in the bore with threads for locking the cathode holder. An inner wrench is formed of a handle attached to a shaft inserted through a hole in the locking ring and engaged with the cathode holder to rotate the same for axial positioning. A sleeve wrench is disposed coaxially over the shaft and engaged with the locking ring. The handle and the sleeve wrench each has a plurality of angular position markings thereon mutually alignable to provide rotational reference for precision positioning of the cathode holder.Type: GrantFiled: October 18, 1989Date of Patent: May 8, 1990Assignee: The Perkin-Elmer CorporationInventors: Anthony J. Rotolico, William H. Maidhof
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Patent number: 4924060Abstract: A cap for an arc torch comprises a skirt (10) composed of plastics material having a generally annular shape and surrounding and spaced from the nose (2, 7) of the torch, and a tubular nose-piece (12) composed of refractory material fitted in the free end of the skirt. The arc torch can be applied to plasma-arc cutting torches.Type: GrantFiled: June 2, 1989Date of Patent: May 8, 1990Assignee: L'air Liquide, Societe Anonyme Pour L'etude et L'exploitation des Procedes Georges ClaudeInventor: Michel Delzenne
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Patent number: 4924052Abstract: A method of forming continuous or spot-sequenced lines across the surface of grain oriented steel strip by spark discharge from electrodes closely spaced from said strip, characterized in that the atmosphere through which the discharge is effected is inert. Preferably the inert atmosphere is nitrogen but other gases, e.g. argon may readily be employed.Type: GrantFiled: March 6, 1989Date of Patent: May 8, 1990Assignee: British Steel PlcInventors: Philip Beckley, David Snell
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Patent number: 4918280Abstract: A clamping sleeve for an electrode of a burner, especially a TIG burner, has its bore receiving the electrode offset from the axis of the housing receiving the sleeve so that, upon clamping of the electrode, the electrode is not only pressed against the wall of the bore over a greater part of its length, but is also pressed to the wall of a bore in the housing through which the electrode extends to increase the area over which electric current is delivered to and heat is abstracted from the electrode.Type: GrantFiled: March 1, 1989Date of Patent: April 17, 1990Inventor: Werner Jankus
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Patent number: 4916283Abstract: A plasma arc working apparatus of water cooling type provides a circulation system for circulating cooling water through a circulation passage in order to cool a working plasma arc torch and an introduction device for introducing pressurized gas into the circulation passage in order to drain the cooling water remaining in the circulation passage forcibly therefrom when the power switch for supplying electric power to the working apparatus is switched off.Type: GrantFiled: April 24, 1989Date of Patent: April 10, 1990Assignee: Daihen CorporationInventors: Moritoshi Nagasaka, Kikuo Terayama, Toshihiko Okada, Masanobu Uchida, Hirokazu Kubo
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Patent number: 4916273Abstract: A surface discontinuity is formed along an anode nozzle bore sufficiently upstream of a nozzle exit orifice and of a sufficient size to cause an arc between an electrically conductive end wall of a plamsa-arc torch anode nozzle passage and a coaxial cathode coaxially mounted by an opposite end wall of the torch cylindrical casing having a gas under pressure and at an established vortex flow to pass through the nozzle passage. A boundary layer of the vortex flow of gas along the anode bore wall provides a path for the arc to pass directly to the anode nozzle passage at or just downstream of the disturbance zone provided by the nozzle passage wall surface discontinuity. A counterbore may extend along a portion of the nozzle axis from the nozzle exit axially inwardly to form a radial shoulder with the main bore of the anode nozzle and define the discontinuity.Type: GrantFiled: March 30, 1989Date of Patent: April 10, 1990Inventor: James A. Browning
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Patent number: 4916278Abstract: A method of severing a metal piece into parts in which electrical contacts engage the piece at the end of the severing line and high frequency electrical current is fed to the contacts for the length of time required to at least significantly reduce the tensile strength of the metal along the line, the current being fed to at least one of the contacts through a proximity conductor overlying the line. After such heating of the metal, the portions of the piece can merely be pulled apart. If shaping of the edge faces is desired, they can be pressed together while heated and malleable and after separation or can be pressed against an anvil while heated and malleable. Before separation, the portions on opposite sides of the line can be pushed toward each other or be moved transversely to each other. If the metal along the line is heated to "burning" temperature, the portions can be separated by burning out the heated metal with an oxygen containing gas.Type: GrantFiled: September 1, 1989Date of Patent: April 10, 1990Assignee: Thermatool CorporationInventors: Wallace C. Rudd, Humfrey N. Udall
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Patent number: 4902871Abstract: In a plasma arc torch, an electrode is movable axially into and out of electrical connection with an anode, typically a nozzle secured to one end of a torch body. A flow of pressurized plasma gas is directed to a plasma chamber between the electrode and the nozzle, preferably through a replaceable swirl ring that closely surrounds and guides the electrode at a larger diameter shoulder portion of the electrode. A gas flow passage, preferably a spiral passage machined on the outer side surface of the shoulder portion, diverts a portion of the gas flow from the plasma chamber to a region above the electrode where it is vented to atmosphere. The passage is sufficiently constricted that a substantial pressure drop appears along the path, while at the same time allowing a sufficient flow to produce the desired cooling. The revolutions of the spiral are preferably closely spaced to enhance the surface area of the electrode in a heat transfer relationship with the cooling gas flow.Type: GrantFiled: September 26, 1988Date of Patent: February 20, 1990Assignee: Hypertherm, Inc.Inventors: Nicholas A. Sanders, Richard W. Couch, Jr.
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Patent number: 4896849Abstract: A system is described for maintaining a sample material in a molten state and away from the walls of a container in a microgravity environment, as in a space vehicle. A plurality of sources of electromagnetic radiation, such as an infrared wavelength, are spaced about the object, with the total net electromagnetic radiation applied to the object being sufficient to maintain it in a molten state, and with the vector sum of the applied radiation being in a direction to maintain the sample close to a predetermined location away from the walls of a container surrounding the sample. For a processing system in a space vehicle that orbits the Earth, the net radiation vector is opposite the velocity of the orbiting vehicle.Type: GrantFiled: June 26, 1987Date of Patent: January 30, 1990Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space AdministrationInventor: Philip I. Moynihan
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Patent number: 4891490Abstract: This invention relates to a plasma torch and a first and second electrode for use in a plasma torch. Each electrode includes a tubular intermediate part which is intended to come into contact with the arc feet and a pair of end parts which are intended to facilitate connection of the electrode to the other parts of the torch. Each electrode is disposed within an enclosed fluid circulation chamber within which a cooling fluid circulates. The intermediate and end parts of each electrode are at least ten millimeters thick. The individual parts of each electrode are connected together by a moisture-impervious, disassemblable, mechanical assembly which prevents the cooling fluid from coming in contact with the interior of the electrodes.Type: GrantFiled: April 29, 1988Date of Patent: January 2, 1990Assignee: Aerospatiale Societe Nationale IndustrielleInventors: Maxime Labrot, Didier Pineau, Jean Feuillerat
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Patent number: 4879446Abstract: A welding torch for gas tungsten arc welding apparatus has a filler metal wire guide positioned within the torch, and within the shielding gas nozzle. The wire guide is adjacent the tungsten electrode and has a ceramic liner through which the wire is fed. This reduces the size of the torch and eliminates the outside clearance problems that exist with external wire guides. Additionally, since the wire is always within the shielding gas, oxidizing of the wire is eliminated.Type: GrantFiled: December 5, 1988Date of Patent: November 7, 1989Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space AdministrationInventors: Gene E. Morgan, Gerald E. Dyer
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Patent number: 4864097Abstract: A plasma arc torch is disclosed as having an elongated hollow body defining a plenum cavity into which an electrode is mounted. The body has a tip end section which is provided with an arc constricting orifice to permit gas injected into the plenum cavity to issue from the arc constricting orifice. Surrounding the arc constricting orifice on an outer surface of the tip end section is an outwardly extending enlarged head portion. Thus, when an arc is established between the tip and electrode in the vicinity of gas passing through the plenum cavity, an arc is formed which is confined and controlled by the outwardly extending enlarged head portion during operation, for example, on a workpiece. In order to start the arc within the center of the electrode, the electrode has a central part thereof in closest proximity to an inner surface of the body adjacent the arc constricting orifice.Type: GrantFiled: September 23, 1988Date of Patent: September 5, 1989Assignee: Emerson Electric Co.Inventor: Manfred J. Wallner
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Patent number: 4863509Abstract: Liquid metal undergoes rapid rotational motion in an induction field and utilizes the resultant centrifugal forces to extend the metal in the form of a rotating film, the film becoming progressively thinner, along a baffle surface located in the induction field. The liquid metal can then emerge through the baffle surface in the form of wires or can be reduced in size on a cylindrical impact wall and then cooled.Type: GrantFiled: September 16, 1987Date of Patent: September 5, 1989Assignee: Centrem S.A.Inventor: Paul Metz
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Patent number: 4861962Abstract: A plasma arc cutting torch, particularly one operating in the 0-200 ampere range, has a shield mounted at its lower end adjacent a workpiece to block splattered molten metal from reaching a nozzle of the torch. The shield is electrically insulated, preferably by mounting it on an insulating ring that is itself secured on a cap screwed onto the torch body. A secondary gas flow through the torch passes through the space between the nozzle and the shield to provide cooling. Bleed ports in the shield allow an enhanced flow rate with the remaining flow being at a rate, in conjunction with the size of an exit orifice in the shield, to stabilize the plasma arc. Canted ports in the secondary gas flow path produce a swirling of the gas flow which enhances the quality of the cut.Type: GrantFiled: June 7, 1988Date of Patent: August 29, 1989Assignee: Hypertherm, Inc.Inventors: Nicholas A. Sanders, Richard W. Couch, Jr.
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Patent number: 4856311Abstract: Apparatus and methods are disclosed for the rapid generation of high hydrostatic pressures and the concurrent delivery of said pressures to a workpiece. The apparatus and methods comprise the rapid thermal expansion and vaporization of a volatile fluid. The volatile fluid is typically liquid argon and heated typically by way of a controllable electric heater, delivered to the workpiece typically by way of a pressure-rupturable membrane. The disclosed apparatus and methods permit the application of high hydrostatic pressures to commercial-scale workpieces, in an economic manner and with reduced cycle times.Type: GrantFiled: June 11, 1987Date of Patent: August 15, 1989Assignee: Vital Force, Inc.Inventor: Robert M. Conaway
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Patent number: 4855563Abstract: The device includes a cathode assembly (1) having a housing (3) and an electrode (6) with a tapering portion (19), and an anode assembly (2) having a housing (20) and a nozzle (12) receiving the tapering portion (19) of the electrode (6), the nozzle (12) successively defining a cylindrical chamber (11), a tapering chamber (21), an arcing chamber (7) and a plasma jet forming chamber (23). The smaller end of the frustoconical tapering portion (19) of the electrode (6) is the end face of the electrode (6) received in the cylindrical and tapering chambers (11 and 21) so that the distance from the end face of the electrode (6) to the arcing chamber (7) equals 0.1 to 0.5 of the length of the tapering chamber (21), and the length of the tapering portion (19) of the electrode (6) is 3.5 to 4.5 times the diameter of the electrode (6).Type: GrantFiled: April 8, 1988Date of Patent: August 8, 1989Inventors: Alexei S. Beresnev, Leonid A. Serykh, Viktor S. Saveliev, Valery S. Volkoedov, Igor V. Stupin
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Patent number: 4855566Abstract: The invention relates to a process for striking an arc and to a torch employing said process. An electronic ignitor located at a maximum distance of 8 meters from the torch has a high-voltage conductor which leads to a spark gap adjacent the part to be welded. The high-voltage circuit is closed in the region of the zone to be ionized between the welding electrode and the part.Type: GrantFiled: April 20, 1987Date of Patent: August 8, 1989Assignee: L'Air LiquideInventors: Jean-Francois Hays, Pierre Legrand, Eric Verna, Michel Delzenne, Bernard Reynaud, Pierre Gaillard
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Patent number: 4851636Abstract: A method and apparatus for generating a plasma arc used in arc welding, arc transformation hardening, minute working, etc. A plasma gas used for generating a plasma arc includes xenon. A tungsten electrode having a diameter of 0.5 millimeters or less is used. Thus, an extremely low plasma arc current of 0.1 amperes or less can be produced in a stabilized manner.Type: GrantFiled: September 11, 1987Date of Patent: July 25, 1989Assignee: Kabushi Kaisha Toyota Chuo KenkyushoInventors: Hisashi Sugimoto, Goro Watanabe
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Patent number: 4847466Abstract: The invention concerns plasma torches comprising an upstream electrode (12), a downstream electrode (11), a chamber (15) for the injection of plasma producing gas, a priming electrode (13) and optionally a magnetic field coil (14), in which the upstream root of the arc is displaced on the upstream electrode. According to the invention, in order to control a continuous or reciprocating and/or an oscillatory translation, the field coil is supplied with a variable direct current, if need be a pulsatory undulatory current, and/or a diffuser is placed at the inner end of the upstream electrode which is supplied with a modulated flow of gas which it causes to whirl. Application in high power plasma torches for regularizing and rendering uniform the wear of the electrodes so as to prolong the life thereof.Type: GrantFiled: January 6, 1988Date of Patent: July 11, 1989Assignees: Electricite de France-Service National, Aerospatiale Societe Nationale IndustrielleInventors: Pierre Pasquini, Maxime Labrot, Jean-Pierre Serrano, Didier Pineau
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Patent number: 4843208Abstract: A plasma torch head adapted to cut longitudinal slots in tubes from the interior is disclosed. The plasma torch head includes an outer body made of reinforced fiberglass. An adhesive is used to affix fiberglass components of the torch head together to form a gas tight seal. As a cut is made, the outer body of the torch becomes charred. At the end of each cut the torch head is either replaced or rebuilt. Gas to support the plasma and electric power is supplied to the torch head via an electrically conductive tube concentric with the major axis of the torch head.Type: GrantFiled: December 23, 1987Date of Patent: June 27, 1989Assignee: EPRIInventors: Thomas J. French, Lester R. Harrell, Anthony L. Dellinger
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Patent number: 4816637Abstract: A plasma arc cutting torch and method for obtaining more efficient cuts underwater, and for muffling the noise and radiation of a plasma cutting torch when used above water, surrounds the plasma arc with high-pressure, high-velocity annular flows of air and water. In one embodiment, a radially inward air flow creates a high-pressure, water-free cutting zone around the plasma while a surrounding radially outward water flow cooperates with and stabilizes the air flow. The water-free cutting zone created during underwater cutting, or above-water cutting on a water-table, includes the cut itself and the underside of the workpiece in the vicinity of the plasma. The air flow prevents water from interfering with the progress of the cut and hydrogen gas from accumulating under the workpiece.Type: GrantFiled: June 2, 1987Date of Patent: March 28, 1989Assignee: Hypertherm, Inc.Inventors: Nicholas A. Sanders, Richard W. Couch, Jr.
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Patent number: 4812611Abstract: A gas flow device for a welding electrode includes a metal sleeve to form a concentric chamber surrounding the electrode, a plastic cap enclosing the rear end of the chamber, an inert gas inlet into the chamber and a quantity of steel wool between the forward end of the chamber and the electrode.Type: GrantFiled: December 20, 1985Date of Patent: March 14, 1989Assignee: North American Philips CorporationInventor: Samuel A. Carleton
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Patent number: 4806722Abstract: A welding torch comprises a head (1) and two current-supply conduits (3) which are held with one of their ends to a body (7) of the torch. The current-supply conduits (3) are connected to the head (1) through connectors (5) held at the other ends of the conduits (3) so as to face each other. The connectors (5) are fitted into holes (2) provided in the head (1) and so shaped as to suit the shape of the external surface of the connectors (5). Through ducts (10) are provided in the connectors (5) to establish communication between the interior space of the head (1) and that of the current-supply conduits (3).Type: GrantFiled: October 28, 1987Date of Patent: February 21, 1989Assignee: Vsesojuzny Nauchno-Issledovatelsky Proektno-konstruktorsky I Tekhnologichesky Institut Elektrosvarochnogo OborudovaniaInventor: Alfred V. Ivannikov
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Patent number: 4804817Abstract: A tool having a rotating hollow electrode is provided power through a rotary electrical connection in the form of ball bearings and conductive lubricant, with a fixed hollow power supply fitting mounted in and insulated from a housing structure journaled in the bearings. Gas for welding is supplied through the hollow fitting and electrode which are in fluid communication.Type: GrantFiled: March 23, 1987Date of Patent: February 14, 1989Assignee: Combustion Engineering, Inc.Inventor: Mark A. Overbay
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Patent number: 4803339Abstract: An improved hollow electrode 10 and hollow electrode working tip 14 for a gas tunsten arc welding apparatus is disclosed. The hollow electrode face is formed as a lune-shaped radial surface 16 having two tapered intersecting cone-shaped angled surfaces 18. The improved electrode working tip provides a controllable stable arc resulting in an improved weld.Type: GrantFiled: September 16, 1987Date of Patent: February 7, 1989Assignee: Rockwell International CorporationInventors: Stephen S. Gordon, Gerald E. Dyer, Lee A. Flanigan
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Patent number: 4792657Abstract: A plasma cutting system comprising a frame, a work support on said frame and a tubular torch support. Gantry apparatus for moving the tubular torch support laterally and longitudinally relative to work on the work support. The torch support is moved a fixed distance from the work and has a ski cup on the lower end of the tubular work support to move over the work. The tube is urged downward by a spring so that as the ski cup runs over the work, the tube is lifted and held at a constant distance from the work. A torch support bearing in the lower end of the torch tube freely receives the torch in the tube.Type: GrantFiled: April 24, 1987Date of Patent: December 20, 1988Inventor: James A. Conley
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Patent number: 4791268Abstract: An arc plasma torch includes a moveable cathode and a fixed anode which are automatically separated by the buildup of gas pressure within the torch after a current flow is established between the cathode and the anode. The gas pressure draws a nontransferred pilot arc to produce a plasma jet. The torch is thus contact started, not through contact with an external workpiece, but through internal contact of the cathode and anode. Once the pilot arc is drawn, the torch may be used in the nontransferred mode, or the arc may be easily transferred to a workpiece. In a preferred embodiment, the cathode has a piston part which slidingly moves within a cylinder when sufficient gas pressure is supplied. In another embodiment, the torch is a hand-held unit and permits control of current and gas flow with a single control.Type: GrantFiled: January 30, 1987Date of Patent: December 13, 1988Assignee: Hypertherm, Inc.Inventors: Nicholas A. Sanders, Richard W. Couch, Jr.
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Patent number: 4791266Abstract: An arc welding kit comprising a torch head, a combined source of electric current and of fluid for welding and a composite cable connectible between the fluid/current source and the torch head by means of coupling connectors.The upstream extremity of the composite cable has a coupling connector identical to that of the torch head whereas its downstream extremity has a coupling connector identical to that of the combined source. This enables two or more such cables to be connected in series to extend the range of the torch. Furthermore, an elbow comprising the same coupling connectors may be placed between the torch head and the composite cable, to turn the torch head through a desired angle.The invention is particularly applicable to plasma cutting torches ignited by short-circuiting.Type: GrantFiled: September 15, 1986Date of Patent: December 13, 1988Assignee: L'Air LiquideInventor: Marhic Gerard
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Patent number: 4788408Abstract: An arc plasma generating system includes components for adjusting spacing between the cathode and the anode. A piston affixed to the cathode is slidingly positioned in a cylinder partitioning therein a first chamber and a second chamber. The first chamber is receptive of discharged cooling fluid at reduced pressure. A first valve selectively infuses pressurized control fluid into the second chamber such as to move the piston against the reduced pressure and thereby move the cathode axially in a first direction. A second valve selectively discharges the control fluid from the second chamber such that the reduced pressure in the first chamber moves the piston opposite the first direction. Telescoping tubing affixed between the piston and the end wall of the cylinder is located within the cylinder and conveys cooling fluid to the cathode. A flexible electrical cable connected between the cathode and a source of arc current is located within the cylinder member such as to be cooled by fluid therein.Type: GrantFiled: May 8, 1987Date of Patent: November 29, 1988Assignee: The Perkin-Elmer CorporationInventors: Janusz Wlodarczyk, Henry C. Thompson, Thomas F. Bernecki, Henry A. Budke
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Patent number: 4788401Abstract: The present invention is a tungsten inert gas or similar welding torch which is readily adjustable in length for different welding situations. The torch has a relatively conventional head with a heat shield attached at the lower end. The heat shield serves as a resilient telescopic mounting for the gas cup which surrounds the electrode. It further serves to give thermal and mechanical isolation between the torch head and gas cup. A gas diffusion screen pack is located within and bears against an inner circumference of the gas cup to provide resilient support and center the cup about the longitudinal axis of the electrode. The gas cup may be extended or retracted a limited distance within the heat shield and may also be rotated if desired. Alternatively, longer or shorter electrode collet bodies can be screwed into the head to provide almost unlimited adjustment of torch length. A gas cup of appropriate length is used with each collet body.Type: GrantFiled: August 17, 1987Date of Patent: November 29, 1988Assignee: C-K Systematics, Inc. div. of Conley & Kleppen, Int'l.Inventor: Arthur L. Kleppen
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Patent number: 4782210Abstract: An electrode used in a plasma-arc torch has ridges formed on the side surface thereof for initiating a pilot arc. The required voltage for initiating a pilot arc is substantially reduced by employing this type of electrode. The ridges have much smaller radii of curvature which substantially enhance the local electric field strength responsible for creating the pilot arc discharge. The ridges are oriented substantially along the flow lines of the plasma gas so as to create the least disturbance. In one embodiment with spiral gas flow, this results in helically oriented ridges. In another embodiment with straight gas flow, the ridges are parallel to the longitudinal axis of the electrode.Type: GrantFiled: June 26, 1987Date of Patent: November 1, 1988Assignee: Thermal Dynamics CorporationInventors: David J. Nelson, William Wakefield, Raymond G. Wilkins
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Patent number: 4777343Abstract: The invention relates to plasma arc apparatus. In plasma arc apparatus it is known to provide a torch, there being provided within the torch an electrode suitably connected to a source of supply, and there being the provision for the passage of gas through the torch and through a nozzle on the torch and for the supply of coolant to reduce the temperature of the electrode and the nozzle during use.Type: GrantFiled: March 28, 1986Date of Patent: October 11, 1988Assignee: D. E. Goodwin Engineering Developments LimitedInventor: David E. Goodwin
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Patent number: 4777342Abstract: In the context of a plasma cutting torch of the type comprising a torch nozzle whose two electrode holders, which are adapted to be connected with different poles of a power supply and are coaxially arranged to form a flow path for gas for operation of the torch, an insulating ring, preferably made of ceramic material, is provided to locate the electrode holders in the axial and radial directions. The invention seeks to devise such an arrangement, using simple and low-price means, so that relative motion between the electrode holders and the electrodes is efficiently precluded and in order to achieve this, each of the two electrode holders is provided with ring holding members with axial gripping surfaces which are able to be moved towards each other axially to hold the ring between them, one of the electrode holders being then placed within the ring and the other being placed around it.Type: GrantFiled: March 2, 1987Date of Patent: October 11, 1988Assignee: Wilhelm Merkle Schweissmaschinenbau GmbHInventor: Josef Hafner
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Patent number: 4771158Abstract: An easily replaceable ventilated external insulator for a tungsten inert gas, plasma, or similar welding torch comprises a generally cylindrical member molded from a resilient heat resistant electrical material such as a silicone rubber. The inner wall of the insulator has a plurality of parallel alternating grooves and lands. The grooves communicate at each end with circumferential grooves which act as manifolds. At least one of these circumferential grooves has a vent to release to the atmosphere any gases formed between the insulator and the body of the torch head during welding operations. The vent is located so that these gases are directed away from the weld zone and do not act to contaminate the welding atmospehre.Type: GrantFiled: August 17, 1987Date of Patent: September 13, 1988Assignee: C-K Systematics, Inc.Inventor: Arthur L. Kleppen
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Patent number: H587Abstract: An arc heater having dual toroidal rear electrodes is disclosed. In this configuration, the total arc current can be doubled without increasing the rear electrode erosion that would result with a single rear electrode. Alternatively, the total arc current can remain the same, and be divided over the two rear electrodes, and the rear electrode erosion is significantly reduced. In the first instance the gas enthalpy performance of the heater is significantly enhanced, and in the second instance the heated gas contamination is reduced and the rear electrode life is increased. The basic components of the arc heater are a forward electrode and dual rear electrodes, the forward and dual rear electrodes being separated from each other by cylindircal multi-segment non-axial conducting constrictor modules. Provision is made for gas injection throughout the device.Type: GrantFiled: October 13, 1987Date of Patent: February 7, 1989Assignee: The United States of America as represented by the Secretary of the Air ForceInventor: James H. Painter