Patents Assigned to The Lincoln Electric Company
  • Patent number: 5118919
    Abstract: In a consumable welding element for depositing a weld metal bead onto a steel workpiece with the diffusible hydrogen in the weld metal being less than 2.0 ppm, the oxygen of the weld metal being less than 0.040% by weight and the yield strength of the weld metal being greater than about 85,000 psi, there is provided an improvement wherein the weld metal is a steel alloy including, as a percentage by weight of the weld metal, 0.03-0.09% carbon, 2.5-4.0% manganese, 0.01-0.05% titanium, silicon less than about 1.0%, nickel less than about 2.0%, and oxygen less than about 0.035%.
    Type: Grant
    Filed: March 29, 1990
    Date of Patent: June 2, 1992
    Assignee: The Lincoln Electric Company
    Inventors: Chang-Shung Chai, David A. Fink, John Gonzalez
  • Patent number: 5117088
    Abstract: A method and apparatus for starting the electric arc of a welder by applying a high frequency, high voltage starting signal across the spark gap between the electrode and workpiece of the welder. This device and method comprises a series resonant circuit having a capacitive reactance element and an inductive reactance element combining to establish a resonant frequency for the series circuit, electrical drive means for energizing the series circuit at a driving frequency near a harmonic of the resonant frequency and means for converting the voltage developed across at least a portion of a designated one of the elements, generally the inductive reactance, into the starting signal.
    Type: Grant
    Filed: March 13, 1991
    Date of Patent: May 26, 1992
    Assignee: The Lincoln Electric Company
    Inventor: Elliott K. Stava
  • Patent number: 5105061
    Abstract: A plasma torch having an electrode with an insert disposed in an insert bore at one end and includes a vent to prevent high pressure cutting oil vapor generated by evaporation of cutting oil trapped in the cavity between the insert and the insert bore. The vent is a groove formed between the cavity and the outer surface of the electrode from pushing the insert out of the insert bore.
    Type: Grant
    Filed: February 15, 1991
    Date of Patent: April 14, 1992
    Assignee: The Lincoln Electric Company
    Inventor: George D. Blankenship
  • Patent number: 5091628
    Abstract: A consumable welding element for arc welding comprising a steel sheath surrounding a compacted core containing metal alloying powders and an essentially 100% basic compound in an amount less than about 1.60% of the total weight of said element. The basic compound is calcium fluoride powder which is preferably in the range of about 0.1% to about 0.9% calcium fluoride powder by total weight of the element. As another feature the core of the element contains a specific agent for decreasing the amount of diffusible hydrogen in the weld metal. This new element may be a filler metal for TIG welding; however, it is preferably a consumable electrode for MIG welding.
    Type: Grant
    Filed: May 20, 1991
    Date of Patent: February 25, 1992
    Assignee: The Lincoln Electric Company
    Inventors: Chang-Shung Chai, David A. Fink, John Gonzalez
  • Patent number: 5060882
    Abstract: A rotative mounting arrangement for a wire supply reel off which the coiled wire thereon is fed by feed rolls comprises a reel mounting spindle axially and rotatively locked within the hub of the reel and provided at its exposed opposite ends with mounting journals for rotatively supporting the spindle in upwardly opening V-shaped trunnion type journal bearings. The spindle journals and trunnion type journal bearings are formed with axially facing cooperating bearing surfaces axially tapered at corresponding relatively steep angles to the spindle axis to have a wedge type bearing interengagement providing a self-adjusting friction drag braking action on the rotative movement of the reel that serves to prevent overrunning of the reel on stoppage of the feeding of the wire supply off the reel.
    Type: Grant
    Filed: April 6, 1990
    Date of Patent: October 29, 1991
    Assignee: The Lincoln Electric Company
    Inventors: Eric R. Rousculp, Lee E. Seufer, Ralph M. Samodell
  • Patent number: 5055655
    Abstract: A consumable welding element for arc welding comprising a steel sheath surrounding a compacted core containing metal alloying powders and an essentially 100% basic compound in an amount less than about 1.60% of the total weight of said element. The basic compound is calcium fluoride powder which is preferably in the range of about 0.1% to about 0.9% calcium fluoride powder by total weight of the element. As another feature the core of the element contains a specific agent for decreasing the amount of diffusible hydrogen in the weld metal. This new element may be a filler metal for TIG welding; however, it is preferably a consumable electrode for MIG welding.
    Type: Grant
    Filed: March 19, 1990
    Date of Patent: October 8, 1991
    Assignee: The Lincoln Electric Company
    Inventors: Chang-Shung Chai, David A. Fink, John Gonzalez
  • Patent number: 5015823
    Abstract: A high manganese weld bead and electrode for producing same which has higher abrasion resistance and hardness than heretofore and is economical to manufacture. The deposit contains approximately 0.4-0.7% C, 10-16% Mn and 4.5 to 7.5% Cr.
    Type: Grant
    Filed: August 21, 1989
    Date of Patent: May 14, 1991
    Assignee: The Lincoln Electric Company
    Inventors: Dennis D. Crockett, Robert P. Munz
  • Patent number: 5003155
    Abstract: A consumable welding element for arc welding comprising a steel sheath surrounding a compacted core containing metal alloying powders and an essentially 100% basic compound in an amount less than about 1.60% of the total weight of said element. The basic compound is calcium fluoride powder which is preferably in the range of about 0.1% to about 0.9% calcium fluoride powder by total weight of the element. As another feature the core of the element contains a specific agent for decreasing the amount of diffusible hydrogen in the weld metal. This new element may be a filler metal for TIG welding; however, it is preferably a consumable electrode for MIG welding.
    Type: Grant
    Filed: September 11, 1989
    Date of Patent: March 26, 1991
    Assignee: The Lincoln Electric Company
    Inventors: Chang-Shung Chai, David A. Fink, John Gonzalez
  • Patent number: 5003154
    Abstract: Apparatus and method to reduce splatter and allow better semi-automatic welding in short circuiting arc welding of the type using a single D.C. power supply for causing a welding current to pass through a welding wire extending variable distances from a holder and between the welding wire and a workpiece at a molten pool on the workpiece. The welding current flows in response to an arc voltage while the welding wire is fed from the holder toward the workpiece whereby the welding wire is subjected to a succession of welding cycles each of which include an arcing condition during which the wire is spaced from the pool and a short circuit condition during which a molten metal ball formed on the end of the wire contacts the metal pool and then transfers from the wire to the workpieced by a necking action. A preselected, constant amount of energy is applied to the wire during the arcing condition for each welding cycle.
    Type: Grant
    Filed: July 3, 1989
    Date of Patent: March 26, 1991
    Assignee: The Lincoln Electric Company
    Inventors: John M Parks, Elliott K. Stava
  • Patent number: 5001326
    Abstract: An improvement in a short circuiting arc welding apparatus of the type including a power supply for causing a welding current of different levels to pass through a welding wire extending at variable extension distances from a holder and between the wire and a workpiece at a molten metal pool on the workpiece. This improvement includes control means for maintaining a generally constant wattage in the wire during the plasma boost portion of the arcing condition as the extension distance from the holder changes. Further, the improvement involves controlling the plasma or arcing condition after a plasma boost by a current curve gradually decreasing from the plasma boost portion toward the background current level for the system.
    Type: Grant
    Filed: February 6, 1990
    Date of Patent: March 19, 1991
    Assignee: The Lincoln Electric Company
    Inventor: Elliott K. Stava
  • Patent number: 4972064
    Abstract: An improvement in a short circuiting arc welding apparatus comprising a single D.C. power supply causing a welding current to pass through a welding wire extending from a holder and between said wire and workpiece at a molten metal pool on the workpiece, wherein the current flows in response to an arc voltage and the welding wire is subjected to a succession of welding cycles. Each of the welding cycles includes an arcing condition during which said wire is spaced from the pool and the energy applied to said wire exceeds a given value raising the temperature at the end of the wire to a molten temperature to form a molten metal ball on the end of the wire and a short circuit condition during which the molten metal ball on the end of the wire first contacts said molten metal pool and then transfers from the wire to the workpiece by a necking action breaking the molten metal ball from the wire to initiate an arc in a subsequent welding cycle. The welding cycles have a generally fixed frequency of repetition.
    Type: Grant
    Filed: September 8, 1989
    Date of Patent: November 20, 1990
    Assignee: The Lincoln Electric Company
    Inventor: Elliott K. Stava
  • Patent number: 4954691
    Abstract: A method and device for controlling a power supply for arc welding in a manner to reduce spatter when the power supply is employed for depositing metal from a welding wire or electrode onto a workpiece by the short circuiting transfer mode wherein a welding current causes the welding wire to alternate between a short circuit condition and an arc condition with metal transfer occurring during a short circuit condition. This method and device includes the concept of shifting the welding current to a background current value in response to a short circuit condition, holding the welding current generally at the background current level for a preselected time, then allowing the welding current to reach the normal unimpeded current level, and causing the holding step to be terminated before the selected time in response to a detected arc condition.
    Type: Grant
    Filed: April 24, 1989
    Date of Patent: September 4, 1990
    Assignee: The Lincoln Electric Company
    Inventors: John M. Parks, Elliott K. Stava
  • Patent number: 4947021
    Abstract: A method and apparatus for TIG welding by passing an alternating current between a non-consumable electrode and a workpiece to form an arc, which apparatus comprises a single reactor with first and second coil portions and a common core, passing a direct current from a direct current power supply through the first coil portion of the reactor and in a negative direction from the workpiece to the electrode for creating a heating cycle, switchably disconnecting the direct current power supply from the circuit and immediately connecting the second coil portion of the reactor in a positive direction across the electrode and workpiece for creating a short cleaning cycle for cleaning the workpiece preparatory to the next heating cycle. These heating and cleaning cycles are continued to create a TIG welding process.
    Type: Grant
    Filed: May 30, 1989
    Date of Patent: August 7, 1990
    Assignee: The Lincoln Electric Company
    Inventor: Elliott K. Stava
  • Patent number: 4929811
    Abstract: A plasma arc torch system includes a fault detect circuit for sensing a short between the electrode and the nozzle and disabling the power supply when the short is sensed. A sensing circuit within the torch cable is provided for actuating the fault detect circuit when the cable is severely punctured. The sensing circuit includes a foil embedded within the cable which circumscribes the main conductor to which a drain lead is connected. The drain lead senses a short between the foil and main conductor from a penetrating foreign object and actuates the fault detect circuit. Additionally, the fault detect circuit is effective in combination with a unique continuity interlock circuit disclosed to insure a safe torch. Further, a rectified control circuit is provided to maintain a stable arc preventing erosion of the nozzle and subsequent exposure of the electrode.
    Type: Grant
    Filed: December 5, 1988
    Date of Patent: May 29, 1990
    Assignee: The Lincoln Electric Company
    Inventor: George D. Blankenship
  • Patent number: 4897522
    Abstract: A control circuit is provided for the output of a high frequency inverter of the type having an output transformer with a core, primary windings and a secondary winding with two sections for creating a first secondary current pulse of electrical current in one section when the primary windings magnetizes the core and a second secondary current pulse in the other of the secondary sections when the primary windings remagnetizes the core. By alternating switch means for passing current through the primaries to magnetize and remagnetize the core at a preselected rate the output current pulses are provided by the two sections of secondary windings. The control circuit of the present invention involves a modification of the output transformer secondary stage. A first auxiliary winding is connected to one of the secondary sections to create an auxiliary current pulse as the core of the transformer is magnetized.
    Type: Grant
    Filed: February 6, 1989
    Date of Patent: January 30, 1990
    Assignee: The Lincoln Electric Company
    Inventors: Dale L. Bilczo, Larry L. Church, Michael J. Kurchak
  • Patent number: 4897523
    Abstract: In a short circuiting arc welding apparatus and method wherein a continuously fed welding wire alternates between an arcing condition during which the wire is spaced from the molten pool of the workpiece and a short circuit condition during which the melted metal on the end of the welding wire is in contact with the molten metal pool and thereafter transfers to the workpiece by a necking action breaking the melted metal from the wire, there is provided an improvement including providing a first high inductance current control circuit for continuously directing a low level, arc sustaining, background current between the welding wire and the workpiece and providing a second current control circuit for controlling current flow during the arcing condition of the process.
    Type: Grant
    Filed: February 10, 1989
    Date of Patent: January 30, 1990
    Assignee: The Lincoln Electric Company
    Inventors: John M. Parks, Elliott K. Stava
  • Patent number: 4897773
    Abstract: There is provided an improvement in an inverter power supply of the type including an output transformer of the type having a high permeability magnetic core, input winding means for applying input current pulses to the core; a first output winding wound on the core; and a second output winding wound on the core. The power supply further includes first and second output terminals and output circuit means for connecting the individual output windings to the terminals in a fashion that opposite polarity output current pulses induced in the output windings by the input current pulses are applied across the terminals in a preselected first polarity.
    Type: Grant
    Filed: May 3, 1989
    Date of Patent: January 30, 1990
    Assignee: The Lincoln Electric Company
    Inventor: Dale L. Bilczo
  • Patent number: 4866247
    Abstract: Apparatus and method to reduce spatter and allow better semi-automatic welding in short circuiting arc welding of the type using a single D.C. power supply for causing a welding current to pass through a welding wire extending variable distances from a holder and between the welding wire and a workpiece at a molten metal pool on the workpiece. The welding current flows in response to an arc voltage while the welding wire is fed from the holder toward the workpiece whereby the welding wire is subjected to a succession of welding cycles each of which include an arcing condition during which the wire is spaced from the pool and a short circuit condition during which a molten metal ball formed on the end of the wire contacts the metal pool and then transfers from the wire to the workpiece by a necking action.
    Type: Grant
    Filed: November 14, 1988
    Date of Patent: September 12, 1989
    Assignee: The Lincoln Electric Company
    Inventors: John M. Parks, Elliott K. Stava
  • Patent number: 4861965
    Abstract: A method and apparatus for TIG welding by passing an alternating current between a non-consumable electrode and a workpiece to form an arc, which apparatus comprises a single reactor, passing a direct current from a direct current power supply through a first portion of the reactor and in a negative direction from the workpiece to the electrode for creating a heating cycle, switchably disconnecting the direct current power supply from the circuit and immediately connecting the second portion of the reactor in a positive direction across the electrode and workpiece for creating a short cleaning cycle for cleaning the workpiece preparatory to the next heating cycle. These cycles are continued to create a TIG welding process.
    Type: Grant
    Filed: December 29, 1987
    Date of Patent: August 29, 1989
    Assignee: The Lincoln Electric Company
    Inventor: Elliott K. Stava
  • Patent number: 4835360
    Abstract: A method and device for controlling a power supply for arc welding in a manner to reduce spatter when the power supply is employed for depositing metal from a welding wire or electrode onto a workpiece by the short circuiting transfer mode wherein a welding current causes the welding wire to alternate between a short circuit condition and an arc condition with metal transfer occurring during a short circuit condition. This method and device includes the concept of shifting the welding current to a background current value in response to a short circuit condition, holding the welding current generally at the background current level for a preselected time, then allowing the welding current to reach the normal unimpeded current level, and causing the holding step to be terminated before the selected time in response to a detected arc condition.
    Type: Grant
    Filed: October 7, 1987
    Date of Patent: May 30, 1989
    Assignee: The Lincoln Electric Company
    Inventors: John M. Parks, Elliott K. Stava