Patents by Inventor Roger W. Hewett

Roger W. Hewett has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20100294744
    Abstract: A dual mode plasma arc torch and methods of operation thereof are provided, wherein the plasma arc torch is operable with both a high frequency power supply and a contact start power supply.
    Type: Application
    Filed: August 3, 2010
    Publication date: November 25, 2010
    Applicant: Thermal Dynamics Corporation
    Inventors: Roger W. Hewett, Kevin D. Homer-Richardson, Joseph P. Jones, Shiyu Chen, Fred Rogers
  • Patent number: 7582844
    Abstract: Devices and methods are provided that control gas flow to a plasma arc torch local to a torch handle. Generally, a plasma arc torch is provided that comprises a gas control device operable with a torch lead and a torch head, and an activation member operable with the gas control device. Accordingly, the activation member activates the gas control device such that gas flow is supplied from the torch lead to the torch head, and the activation member deactivates the gas control device such that the gas flow is terminated. Further, the activation member may comprise a trigger system, a button, or a safety member, among others. Moreover, the gas control device may comprise a gas control valve or a switch that activates a gas control device disposed within a power supply, among others.
    Type: Grant
    Filed: November 24, 2003
    Date of Patent: September 1, 2009
    Assignee: Thermal Dynamics Corporation
    Inventors: Kevin D. Horner-Richardson, Shiyu Chen, Roger W. Hewett, Joseph P. Jones, Kevin J. Kinderson, Darrin H. MacKenzie, Fred Rogers
  • Patent number: 7429715
    Abstract: A modular plasma arc torch is provided that comprises a torch head and a torch lead, and a quick disconnect that is operatively engaged between the torch head and the torch lead. Accordingly, the torch head and torch lead may be quickly assembled and disassembled through the use of the quick disconnect. Further, the modular plasma arc torch also comprises a gas control device disposed within the plasma arc torch, which is operatively engaged between the torch head and the torch lead through the use of the quick disconnect according to the present invention. In addition, the quick disconnect may be used to connect a wide range of torch components within a plasma arc torch, thereby providing a reconfigurable plasma arc torch. Moreover, the quick disconnect according to the present invention conducts both gas and electric power from a power supply to the torch head for operation of the plasma arc torch.
    Type: Grant
    Filed: February 26, 2002
    Date of Patent: September 30, 2008
    Assignee: Thermal Dynamics Corporation
    Inventors: Darrin H. MacKenzie, Shiyu Chen, Roger W. Hewett, Kevin D. Horner-Richardson, Joseph P. Jones
  • Patent number: 7326874
    Abstract: Vented shield systems for plasma arc torches are provided that comprise a shield cup body defining a distal end portion, a vented retainer secured to the distal end portion of the shield cup body, and a shield cap secured to the vented retainer. The vented retainer defines at least one vent passageway that directs a flow of secondary gas inward toward the shield cap, and the vented shield system blocks at least a portion of molten metal from contacting components, such as a tip or nozzle, of the plasma arc torch. The shield cap may comprise a mechanized cap, a drag cap, a gouging cap, or a deflector cap, among others. Accordingly, various shield caps may be employed without removal or replacement of the vented retainer. The same vented retainer may be used throughout a variety of plasma arc torch applications.
    Type: Grant
    Filed: July 26, 2004
    Date of Patent: February 5, 2008
    Assignee: Thermal Dynamics Corporation
    Inventors: Jonathan Brasseur, Kevin D. Horner-Richardson, Roger W. Hewett
  • Patent number: 7202440
    Abstract: A dual mode plasma arc torch is provided that preferably comprises a start cartridge disposed between an electrode and a tip. In one form, the start cartridge comprises an initiator that is in electrical contact with the electrode and that is resiliently biased into contact with the tip, such that when the plasma arc torch is in a contact start mode, the initiator is movable against the resilient bias to separate from the tip and establish a pilot arc between the initiator and the tip. Further, when the plasma arc torch is in a high frequency start mode, the start cartridge spaces the tip from the electrode such that a pilot arc is established between the electrode and the tip. In other forms, a contact start torch is provided that is operable under high frequency, and conversely, a high frequency start torch is provided that is operable under low voltage.
    Type: Grant
    Filed: July 18, 2005
    Date of Patent: April 10, 2007
    Assignee: Thermal Dynamics Corporation
    Inventors: Roger W. Hewett, Kevin D. Horner-Richardson, Joseph P. Jones, Shiyu Chen, Fred A. Rogers
  • Patent number: 7145099
    Abstract: A tip gas distributor is provided that preferably comprises a plurality of swirl holes and a plurality of secondary gas holes, wherein the swirl holes direct a plasma gas to generate a plasma stream, and the secondary gas holes direct a secondary gas to stabilize the plasma stream. Additionally, a tip gas distributor is provided that comprises swirl passages and secondary gas passages formed between the tip gas distributor and an adjacent component to generate and stabilize the plasma stream. Further, methods of generating and stabilizing the plasma stream are provided through the use of the swirl holes and passages, along with the secondary gas holes and passages.
    Type: Grant
    Filed: March 16, 2004
    Date of Patent: December 5, 2006
    Assignee: Thermal Dynamics Corporation
    Inventors: Kevin D. Homer-Richardson, Joseph P. Jones, Roger W. Hewett, Shiyu Chen
  • Patent number: 6936786
    Abstract: A dual mode plasma arc torch is provided that preferably comprises a start cartridge disposed between an electrode and a tip. In one form, the start cartridge comprises an initiator that is in electrical contact with the electrode and that is resiliently biased into contact with the tip, such that when the plasma arc torch is in a contact start mode, the initiator is movable against the resilient bias to separate from the tip and establish a pilot arc between the initiator and the tip. Further, when the plasma arc torch is in a high frequency start mode, the start cartridge spaces the tip from the electrode such that a pilot arc is established between the electrode and the tip. In other forms, a contact start torch is provided that is operable under high frequency, and conversely, a high frequency start torch is provided that is operable under low voltage.
    Type: Grant
    Filed: November 24, 2003
    Date of Patent: August 30, 2005
    Assignee: Thermal Dynamics Corporation
    Inventors: Roger W. Hewett, Kevin D. Horner-Richardson, Joseph P. Jones, Shiyu Chen, Fred Rogers
  • Patent number: 6914211
    Abstract: Vented shield systems for plasma arc torches are provided that comprise a shield cup body defining a distal end portion, a vented retainer secured to the distal end portion of the shield cup body, and a shield cap secured to the vented retainer. The vented retainer defines at least one vent passageway that directs a flow of secondary gas inward toward the shield cap, and the vented shield system blocks at least a portion of molten metal from contacting components, such as a tip or nozzle, of the plasma arc torch. The shield cap may comprise a mechanized cap, a drag cap, a gouging cap, or a deflector cap, among others. Accordingly, various shield caps may be employed without removal or replacement of the vented retainer. The same vented retainer may be used throughout a variety of plasma arc torch applications.
    Type: Grant
    Filed: February 27, 2003
    Date of Patent: July 5, 2005
    Assignee: Thermal Dynamics Corporation
    Inventors: Jonathan Brasseur, Kevin D. Horner-Richardson, Roger W. Hewett
  • Patent number: 6903301
    Abstract: A contact start plasma arc torch is provided that comprises an electrode, a tip, and an initiator that is resiliently biased into contact with the tip, the initiator being movable against the resilient bias to separate from the tip and establish a pilot arc between the initiator and the tip. The initiator is disposed within a start cartridge, which preferably comprises a coil spring that biases the initiator into contact with the tip. The plasma arc torch further comprises a plurality of head vent holes to vent gas from within the start cartridge during operation of the torch. Additionally, the tip defines a plurality of swirl holes and secondary gas holes to generate and control a plasma stream that is subsequently blown from a central exit orifice in the tip.
    Type: Grant
    Filed: February 26, 2002
    Date of Patent: June 7, 2005
    Assignee: Thermal Dynamics Corporation
    Inventors: Joseph P. Jones, Kevin D. Horner-Richardson, Shiyu Chen, Roger W. Hewett
  • Patent number: 6881921
    Abstract: A plasma arc torch has a threadless electrode-cathode locking assembly, a one-piece tip assembly, and a rotational contact starting mechanism. The cathode and electrode of the locking assembly are configured such that relative rotation of the electrode with respect to the cathode causes the electrode to move in an axial direction relative to the cathode for locking the electrode in fixed axial and rotational position with respect to the cathode. The inner wall of the one-piece tip assembly is configured to receive the forward end of the electrode in a non-contact position. Rotation of the electrode with respect to the tip causes an arcing formation on the electrode to contact an arcing chamber within the cavity. Rotation of the electrode away from the tip generatesa pilot arc in the arcing chamber.
    Type: Grant
    Filed: May 22, 2003
    Date of Patent: April 19, 2005
    Assignee: Thermal Dynamics Corporation
    Inventors: Kevin D. Horner-Richardson, Pearl A. Grant, Roger W. Hewett, Gene V. Hewes, Howard H. Horn
  • Publication number: 20040232118
    Abstract: A plasma arc torch has a threadless electrode-cathode locking assembly, a one-piece tip assembly, and a rotational contact starting mechanism. The cathode and electrode of the locking assembly are configured such that relative rotation of the electrode with respect to the cathode causes the electrode to move in an axial direction relative to the cathode for locking the electrode in fixed axial and rotational position with respect to the cathode. The inner wall of the one-piece tip assembly is configured to receive the forward end of the electrode in a non-contact position. Rotation of the electrode with respect to the tip causes an arcing formation on the electrode to contact an arcing chamber within the cavity. Rotation of the electrode away from the tip generates a pilot arc in the arcing chamber.
    Type: Application
    Filed: May 22, 2003
    Publication date: November 25, 2004
    Inventors: Kevin D. Horner-Richardson, Pearl A. Grant, Roger W. Hewett, Gene V. Hewes, Howard H. Horn
  • Publication number: 20040173582
    Abstract: A tip gas distributor is provided that preferably comprises a plurality of swirl holes and a plurality of secondary gas holes, wherein the swirl holes direct a plasma gas to generate a plasma stream, and the secondary gas holes direct a secondary gas to stabilize the plasma stream. Additionally, a tip gas distributor is provided that comprises swirl passages and secondary gas passages formed between the tip gas distributor and an adjacent component to generate and stabilize the plasma stream. Further, methods of generating and stabilizing the plasma stream are provided through the use of the swirl holes and passages, along with the secondary gas holes and passages.
    Type: Application
    Filed: March 16, 2004
    Publication date: September 9, 2004
    Inventors: Kevin D. Homer-Richardson, Joseph P. Jones, Roger W. Hewett, Shiyu Chen
  • Publication number: 20040169018
    Abstract: Vented shield systems for plasma arc torches are provided that comprise a shield cup body defining a distal end portion, a vented retainer secured to the distal end portion of the shield cup body, and a shield cap secured to the vented retainer. The vented retainer defines at least one vent passageway that directs a flow of secondary gas inward toward the shield cap, and the vented shield system blocks at least a portion of molten metal from contacting components, such as a tip or nozzle, of the plasma arc torch. The shield cap may comprise a mechanized cap, a drag cap, a gouging cap, or a deflector cap, among others. Accordingly, various shield caps may be employed without removal or replacement of the vented retainer. The same vented retainer may be used throughout a variety of plasma arc torch applications.
    Type: Application
    Filed: February 27, 2003
    Publication date: September 2, 2004
    Inventors: Jonathan Brasseur, Kevin D. Horner-Richardson, Roger W. Hewett
  • Patent number: D501632
    Type: Grant
    Filed: January 30, 2003
    Date of Patent: February 8, 2005
    Assignee: Thermal Dynamics Corporation
    Inventors: Roger W. Hewett, Jonathan Brasseur, William M. Wakefield, Sr., Walter Stark
  • Patent number: D504142
    Type: Grant
    Filed: January 30, 2003
    Date of Patent: April 19, 2005
    Assignee: Thermal Dynamics Corporation
    Inventors: Kevin Horner-Richardson, Joseph P. Jones, Roger W. Hewett
  • Patent number: D511280
    Type: Grant
    Filed: September 4, 2002
    Date of Patent: November 8, 2005
    Assignee: Thermal Dynamics Corporation
    Inventors: Kevin Horner-Richardson, Joseph P. Jones, Roger W. Hewett
  • Patent number: D511663
    Type: Grant
    Filed: January 30, 2003
    Date of Patent: November 22, 2005
    Assignee: Thermal Dynamics Corporation
    Inventors: Roger W. Hewett, Jonathan Brasseur, William M. Wakefield, Sr.
  • Patent number: D496842
    Type: Grant
    Filed: September 4, 2002
    Date of Patent: October 5, 2004
    Assignee: Thermal Dynamics Corporation
    Inventors: Shiyu Chen, Kevin Horner-Richardson, Joseph P. Jones, Roger W. Hewett
  • Patent number: D497373
    Type: Grant
    Filed: February 27, 2003
    Date of Patent: October 19, 2004
    Assignee: Thermal Dynamics Corporation
    Inventors: Roger W. Hewett, Jonathan Brasseur
  • Patent number: D499620
    Type: Grant
    Filed: December 26, 2002
    Date of Patent: December 14, 2004
    Assignee: Thermal Dynamics Corporation
    Inventors: Kevin Horner-Richardson, Joseph P. Jones, Roger W. Hewett