Patents by Inventor Toichi Watanabe

Toichi Watanabe 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).

  • Patent number: 5793011
    Abstract: A method and apparatus for continuously spot-welding galvanized steel sheets overlapped to be bonded by way of a spot welding machine having a pair of electrodes. The galvanized steel sheets clamp a resistance increasing material including a spacer to ensure a gap between the sheets. Bonding surfaces of the galvanized steel sheets partly contact each other when the pair of electrodes pressurize the galvanized steel sheets such that a part of the gap is retained around the spacer between the bonding surfaces. The retained gap has a size in which zinc melted or vapored when a weld current flows between the electrodes can escape through a weld section of the galvanized steel sheets to outside. The method comprises the step of recording an inter-electrode resistance for each spot when the continuous spot welding is executed by the pair of electrodes.
    Type: Grant
    Filed: November 7, 1995
    Date of Patent: August 11, 1998
    Assignees: Toichi Watanabe, Kabushiki Kaisha Toyoda Jidoshokki Seisakusho, Research Development Corporation of Japan
    Inventors: Toichi Watanabe, Tadashi Sofue
  • Patent number: 5075531
    Abstract: An electric resistance welding method for welding zinc plated steel plates. The zinc plated steel plates having at least one surface covered with a plating layer composed of mainly zinc can be welded by the present invention efficiently while overlapping said plating layers, because a material for increasing the resistance between the zinc plated steel plates is employed in the present invention, and it is either spreaded, coated or bonded on the surface of said plating layers to be joined beforehand. Thus, the electric resistance of zinc plated steel plates can be performed by a lower electric current in a shorter time without deteriorating the anti-corrosion property of zinc plated steel plates, because the electric resistance between the steel plates has been increased by such a material.
    Type: Grant
    Filed: October 31, 1989
    Date of Patent: December 24, 1991
    Assignees: Kabushiki Kaisha Toyoda Jidoshokki Seisakusho, Toichi Watanabe
    Inventors: Tadashi Sofue, Toichi Watanabe
  • Patent number: 4922075
    Abstract: An electric resistance welding method for welding zinc plated steel plates is disclosed. The zinc plated steel plates having at least one surface covered with a plating layer composed of mainly zinc can be welded by the present invention efficiently while overlapping said plating layers, because a material for increasing the resistance between the zinc plated steel plates is employed in the present invention, and it is either spreaded, coated or bonded on the surface of said plating layers to be joined beforehand. Thus, the electric resistance of zinc plated steel plates can be performed by a lower electric current in a shorter time without deteriorating the anti-corrosion property of zinc plated steel plates, because the electric resistance between the steel plates has been increased by such a material.
    Type: Grant
    Filed: November 3, 1987
    Date of Patent: May 1, 1990
    Assignee: Kabushi Kaisha Toyoda Jidoshokki Seisakusho
    Inventors: Tadashi Sofue, Toichi Watanabe
  • Patent number: RE37799
    Abstract: A method and apparatus for continuously spot-welding galvanized steel sheets overlapped to be bonded by way of a spot welding machine having a pair of electrodes. The galvanized steel sheets clamp a resistance increasing material including a spacer to ensure a gap between the sheets. Bonding surfaces of the galvanized steel sheets partly contact each other when the pair of electrodes pressurize the galvanized steel sheets such that a part of the gap is retained around the spacer between the bonding surfaces. The retained gap has a size in which zinc melted or vapored when a weld current flows between the electrodes can escape through a weld section of the galvanized steel sheets to outside. The method comprises the step of recording an inter-electrode resistance for each spot when the continuous spot welding is executed by the pair of electrodes.
    Type: Grant
    Filed: August 11, 2000
    Date of Patent: July 23, 2002
    Assignees: Kabushiki Kaisha Toyoda Jidoshokki Seisakusho, Research Development Corporation of Japan
    Inventors: Toichi Watanabe, Tadashi Sofue