Patents Assigned to Waterworks Technology Development Organization Co., Ltd.
  • Patent number: 6203073
    Abstract: A tube joint comprises: a pushing ring provided at its outer periphery with a projection and fitted to an outer periphery of one end of a joint tube; a tube or a joint body provided at is side opposed to the pushing ring with a projection opposed to the projection of the pushing ring, the tube or the joint body having a receiving portion which is widened toward the pushing ring and the tube or the joint body being fitted to an outer periphery of the joint tube with a peripheral gap left therebetween; a fastening tool capable of moving the pushing ring in a direction of the tube or the joint body; a packing provided between inner and outer side of the tube or the joint body and the joint tube, and fitted through the receiving portion by its own resilient deformation by operation of the fastening tool; and a spacer inserted between the pushing ring and the tube or the joint body to limit a distance between the pushing ring and the tube or the joint body to a constant value.
    Type: Grant
    Filed: September 9, 1999
    Date of Patent: March 20, 2001
    Assignee: Waterworks Technology Development Organization Co., Ltd.
    Inventors: Taichi Sato, Koichi Shirakawa, Kosuke Sakai
  • Patent number: 6161878
    Abstract: An external cover pipe is adapted to be fixedly fitted over a fluid transport pipe made of synthetic resin via an elastic seal. The cover pipe includes a plurality of split pipe members divided in the peripheral direction of the pipe which cooperate to compress the elastic seal in association with a fastening operation of a fastener for fastening and joining together the split pipe members disposed adjacent each other in the peripheral direction. Each split pipe member includes, in an inner peripheral face thereof, a deformation limiting face for coming into contact with an outer peripheral face of the fluid transport pipe in association with the fastening operation of the fastener so as to limit radial deformation of the fluid transport pipe. This deformation limiting face is provided at a portion in the inner peripheral face of the split pipe member located at a position axially offset toward an extreme axial end of the external cover pipe away from a portion thereof where the elastic seal is attached.
    Type: Grant
    Filed: August 26, 1998
    Date of Patent: December 19, 2000
    Assignee: Waterworks Technology Development Organization Co., Ltd.
    Inventors: Kazuhiro Atsumi, Kikuo Saito, Yasushi Shimonaka, Tamotsu Maenishi
  • Patent number: 6131957
    Abstract: A construction for fixing a pipe joint is disclosed. The construction includes a pipe joint body within which a fluid transport pipe is connected and engaged in a sealed state via an elastic seal, a press ring fitted on the fluid transport pipe, the press ring being peripherally divided to provide a plurality of press-ring segments, a fastener for fasting each press-ring segment to a connecting portion of the pipe joint body along a pipe axis direction, and a retainer member interposed between an outer peripheral face of the fluid transport pipe and an inner peripheral face of the press ring, the retainer member being capable of radially biting into the outer peripheral face of the fluid transport pipe. A cam surface formed in the inner peripheral face of the press ring is operable to reduce the retainer member radially with a relative movement between the pipe joint body and the press ring along the pipe axis direction in association with a fastening operation by the fastener.
    Type: Grant
    Filed: March 17, 1999
    Date of Patent: October 17, 2000
    Assignee: Waterworks Technology Development Organization Co., Ltd.
    Inventors: Kikuo Saito, Tamotsu Maenishi
  • Patent number: 6056329
    Abstract: A telescopic pivotal pipe joint for use in a fluid transporting pipe system such as water transporting pipe system installed under the ground is disclosed. The joint has a first pipe member including a semi-spherical inner peripheral face, a second pipe member including a semi-spherical pipe portion projecting radially outward and sidable along the semi-spherical inner peripheral face of the first pipe member, the second pipe member being slidably engaged within the first pipe member, and a third pipe member telescopically sidable in an axial direction and engaged on a straight pipe portion co-extensive with the semi-spherical pipe portion of the second pipe member. The semi-spherical pipe portion of the second pipe member defines an annular groove, into which one end of the third pipe member comes into engagement along the axial direction when the second pipe member and the third pipe member are contracted maximally relative to each other.
    Type: Grant
    Filed: April 1, 1998
    Date of Patent: May 2, 2000
    Assignee: Waterworks Technology Development Organization Co., Ltd.
    Inventors: Kenji Kitani, Shintaro Suzuki, Kosuke Sakai
  • Patent number: 6019396
    Abstract: A pipe connecting apparatus for connecting a first pipe with a second pipe inserted into the first pipe member is disclosed. The apparatus includes an elastic seal to be disposed within a gap formed between an inner peripheral face of the first pipe and an outer peripheral face of the second pipe, the elastic seal being compressed in an axial direction along the axis of the first pipe for sealing the gap, a press ring fitted on the second pipe, the press ring being movable on the outer peripheral face of the second pipe in the axial direction, and a retainer member fitted on the second pipe, the retainer member having a locked condition in which the retainer member is pressed against the second pipe and a released condition in which the retainer member is radially expanded to be released from the locked condition, the retainer member being switched over from the released condition to the locked condition in association with a movement thereof relative to the press ring.
    Type: Grant
    Filed: August 21, 1998
    Date of Patent: February 1, 2000
    Assignee: Waterworks Technology Development Organization Co., Ltd.
    Inventors: Kikuo Saito, Yasushi Shimonaka, Hideki Yoneyama, Akihito Totsugi
  • Patent number: 5967168
    Abstract: A method of connecting a branch pipe to an existing main pipe is disclosed. The method includes the steps of: connecting and communicating a branch-pipe joint having a branching pipe portion to an existing main pipe; connecting a branch pipe to the branch-pipe joint; and communicating the branch pipe with the existing main pipe through the branch-pipe joint, with all these steps being effected while outflow of fluid from inside the main pipe being prevented. In the above method, the branch pipe is connected with a connecting pipe portion which in turn is connected with the branching pipe portion via a flange joint including a pair of flanges. A shutter plate is inserted between the pair of flanges of the flange joint and communicating the connecting pipe portion with the branching pipe portion thus preventing outflow of the fluid from the branching pipe portion.
    Type: Grant
    Filed: April 3, 1998
    Date of Patent: October 19, 1999
    Assignee: Waterworks Technology Development Organization Co., Ltd.
    Inventors: Kenji Kitani, Shintaro Suzuki, Kosuke Sakai
  • Patent number: 5924436
    Abstract: A connecting construction of a branch pipe is disclosed.
    Type: Grant
    Filed: April 6, 1998
    Date of Patent: July 20, 1999
    Assignee: Waterworks Technology Development Organization Co., Ltd.
    Inventors: Kenji Kitani, Shintaro Suzuki, Kosuke Sakai
  • Patent number: D424916
    Type: Grant
    Filed: October 1, 1999
    Date of Patent: May 16, 2000
    Assignee: Waterworks Technology Development Organization Co., Ltd.
    Inventors: Taichi Sato, Yasushi Fujita
  • Patent number: D424917
    Type: Grant
    Filed: October 1, 1999
    Date of Patent: May 16, 2000
    Assignee: Waterworks Technology Development Organization Co., Ltd.
    Inventors: Taichi Sato, Yasushi Fujita
  • Patent number: D424918
    Type: Grant
    Filed: October 1, 1999
    Date of Patent: May 16, 2000
    Assignee: Waterworks Technology Development Organization Co., Ltd.
    Inventors: Taichi Sato, Yasushi Fujita
  • Patent number: D425406
    Type: Grant
    Filed: October 1, 1999
    Date of Patent: May 23, 2000
    Assignee: Waterworks Technology Development Organization Co., Ltd.
    Inventors: Taichi Sato, Yasushi Fujita
  • Patent number: D425782
    Type: Grant
    Filed: October 1, 1999
    Date of Patent: May 30, 2000
    Assignee: Waterworks Technology Development Organization Co., Ltd.
    Inventors: Taichi Sato, Yasushi Fujita
  • Patent number: D426143
    Type: Grant
    Filed: October 1, 1999
    Date of Patent: June 6, 2000
    Assignee: Waterworks Technology Development Organization Co., Ltd.
    Inventors: Taichi Sato, Yasushi Fujita
  • Patent number: D426144
    Type: Grant
    Filed: October 1, 1999
    Date of Patent: June 6, 2000
    Assignee: Waterworks Technology Development Organization Co., Ltd.
    Inventors: Taichi Sato, Yasushi Fujita
  • Patent number: D426455
    Type: Grant
    Filed: October 1, 1999
    Date of Patent: June 13, 2000
    Assignee: Waterworks Technology Development Organization Co., Ltd.
    Inventors: Taichi Sato, Yasushi Fujita
  • Patent number: D426457
    Type: Grant
    Filed: October 1, 1999
    Date of Patent: June 13, 2000
    Assignee: Waterworks Technology Development Organization Co., Ltd.
    Inventors: Taichi Sato, Yasushi Fujita
  • Patent number: D427508
    Type: Grant
    Filed: September 10, 1999
    Date of Patent: July 4, 2000
    Assignee: Waterworks Technology Development Organization Co., Ltd.
    Inventors: Taichi Sato, Yasushi Fujita
  • Patent number: D428805
    Type: Grant
    Filed: October 1, 1999
    Date of Patent: August 1, 2000
    Assignee: Waterworks Technology Development Organization Co., Ltd.
    Inventors: Taichi Sato, Yasushi Fujita
  • Patent number: D429145
    Type: Grant
    Filed: September 10, 1999
    Date of Patent: August 8, 2000
    Assignee: Waterworks Technology Development Organization Co., Ltd.
    Inventors: Taichi Sato, Yasushi Fujita