Patents by Inventor Masayoshi Yokoi

Masayoshi Yokoi 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: 7422815
    Abstract: A separator is provided with a substrate portion having a predetermined concave-convex shape, an underlying coating layer formed on the substrate portion, a first coating layer coating the substrate portion and the underlying coating layer, and a second coating layer formed thereon. The second coating layer, which is formed from carbon materials, is sufficiently electrically conductive and protects the underlying layers. The first coating layer is formed from a low-melting-point metal subjected to a melting process. The melting process is a process of first conducting heating at such a temperature that melts the low-melting-point metal but does not melt the substrate portion and the underlying coating layer and then conducting cooling. Thus, in the first coating layer, the crystal grain size of the metal is increased and thus the grain boundary density is reduced.
    Type: Grant
    Filed: April 23, 2004
    Date of Patent: September 9, 2008
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Hiromichi Nakata, Masayoshi Yokoi, Joji Yoshimura, Kenichi Suzuki, Fumio Nonoyama
  • Patent number: 7364814
    Abstract: A separator of a fuel cell includes a base material and a surface treatment layer formed on the base material. The surface treatment layer includes a base material-side portion made from metal and a base material opposite-side portion made from carbon formed at an atom level or composite materials of carbon and metal or semi-metal. The surface treatment layer may further include carbon particle composite layer formed on the base material opposite-side portion formed at an atom level. In a manufacturing method of the above separator of a fuel cell, the base material opposite-side portion is formed by dry coating.
    Type: Grant
    Filed: June 3, 2003
    Date of Patent: April 29, 2008
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Hiromichi Nakata, Masayoshi Yokoi, Kenji Shimoda, Noboru Takayanagi
  • Patent number: 7052794
    Abstract: A separator is provided with a substrate portion having a predetermined concave-convex shape, an underlying coating layer formed on the substrate portion, a first coating layer coating the substrate portion and the underlying coating layer, and a second coating layer formed thereon. The second coating layer, which is formed from carbon materials, is sufficiently electrically conductive and protects the underlying layers. The first coating layer is formed from a low-melting-point metal subjected to a melting process. The melting process is a process of first conducting heating at such a temperature that melts the low-melting-point metal but does not melt the substrate portion and the underlying coating layer and then conducting cooling. Thus, in the first coating layer, the crystal grain size of the metal is increased and thus the grain boundary density is reduced.
    Type: Grant
    Filed: April 19, 2001
    Date of Patent: May 30, 2006
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Hiromichi Nakata, Masayoshi Yokoi, Joji Yoshimura, Kenichi Suzuki, Fumio Nonoyama
  • Publication number: 20040197467
    Abstract: A separator is provided with a substrate portion having a predetermined concave-convex shape, an underlying coating layer formed on the substrate portion, a first coating layer coating the substrate portion and the underlying coating layer, and a second coating layer formed thereon. The second coating layer, which is formed from carbon materials, is sufficiently electrically conductive and protects the underlying layers. The first coating layer is formed from a low-melting-point metal subjected to a melting process. The melting process is a process of first conducting heating at such a temperature that melts the low-melting-point metal but does not melt the substrate portion and the underlying coating layer and then conducting cooling. Thus, in the first coating layer, the crystal grain size of the metal is increased and thus the grain boundary density is reduced.
    Type: Application
    Filed: April 23, 2004
    Publication date: October 7, 2004
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Hiromichi Nakata, Masayoshi Yokoi, Joji Yoshimura, Kenichi Suzuki, Fumio Nonoyama
  • Patent number: 6749959
    Abstract: The gas separator is provided with a substrate portion having a predetermined concave-convex shape, an underlying coating layer formed on the substrate portion, a first coating layer for coating the substrate portion and the underlying coating layer, and a second coating layer formed thereon. The second coating layer is formed from a carbon material, and is sufficiently conductive. Moreover, the second coating layer protects the underlying layer. The first coating layer is formed from a noble metal. Therefore, the first coating layer coated with the second coating layer exhibits extremely high corrosion resistance. The underlying coating layer and the substrate portion are coated with the first and second coating layers, so that the progress in corrosion can be sufficiently prevented. Thus, excellent overall corrosion resistance of the separator can be realized.
    Type: Grant
    Filed: March 12, 2001
    Date of Patent: June 15, 2004
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Hiromichi Nakata, Masayoshi Yokoi, Masazumi Onishi, Hideo Aihara, Masashi Murate, Yoshifumi Kaji
  • Publication number: 20030228510
    Abstract: A separator of a fuel cell includes a base material and a surface treatment layer formed on the base material. The surface treatment layer includes a base material-side portion made from metal and a base material opposite-side portion made from carbon formed at an atom level or composite materials of carbon and metal or semi-metal. The surface treatment layer may further include carbon particle composite layer formed on the base material opposite-side portion formed at an atom level. In a manufacturing method of the above separator of a fuel cell, the base material opposite-side portion is formed by dry coating.
    Type: Application
    Filed: June 3, 2003
    Publication date: December 11, 2003
    Inventors: Hiromichi Nakata, Masayoshi Yokoi, Kenji Shimoda, Noboru Takayanagi
  • Publication number: 20010033957
    Abstract: A separator is provided with a substrate portion having a predetermined concave-convex shape, an underlying coating layer formed on the substrate portion, a first coating layer coating the substrate portion and the underlying coating layer, and a second coating layer formed thereon. The second coating layer, which is formed from carbon materials, is sufficiently electrically conductive and protects the underlying layers. The first coating layer is formed from a low-melting-point metal subjected to a melting process. The melting process is a process of first conducting heating at such a temperature that melts the low-melting-point metal but does not melt the substrate portion and the underlying coating layer and then conducting cooling. Thus, in the first coating layer, the crystal grain size of the metal is increased and thus the grain boundary density is reduced.
    Type: Application
    Filed: April 19, 2001
    Publication date: October 25, 2001
    Inventors: Hiromichi Nakata, Masayoshi Yokoi, Joji Yoshimura, Kenichi Suzuki, Fumio Nonoyama
  • Publication number: 20010028974
    Abstract: The gas separator is provided with a substrate portion having a predetermined concave-convex shape, an underlying coating layer formed on the substrate portion, a first coating layer for coating the substrate portion and the underlying coating layer, and a second coating layer formed thereon. The second coating layer is formed from a carbon material, and is sufficiently conductive. Moreover, the second coating layer protects the underlying layer. The first coating layer is formed from a noble metal. Therefore, the first coating layer coated with the second coating layer exhibits extremely high corrosion resistance. The underlying coating layer and the substrate portion are coated with the first and second coating layers, so that the progress in corrosion can be sufficiently prevented. Thus, excellent overall corrosion resistance of the separator can be realized.
    Type: Application
    Filed: March 12, 2001
    Publication date: October 11, 2001
    Inventors: Hiromichi Nakata, Masayoshi Yokoi, Masazumi Onishi, Hideo Aihara, Masashi Murate, Yoshifumi Kaji