Patents Assigned to Asahi Techno Corp.
  • Patent number: 7036577
    Abstract: A groundwater pumping apparatus includes an outer tube, an inner tube, a shield member, a vacuum unit and a pump unit. The outer tube is buried in ground, and has a water-passing portion at its lower part. The inner tube has a substantially same length as the outer tube, and is placed in the outer tube such that the inner tube is spaced from the outer tube. The inner tube has a groundwater inlet at its bottom end, which is provided at a position lower than a top end of the water-passing portion. The shield member shields top ends of the outer tube and the inner tube. The vacuum unit reduces a pressure in the inner tube. The pump unit pumps groundwater that comes in the inner tube through the groundwater inlet.
    Type: Grant
    Filed: July 31, 2001
    Date of Patent: May 2, 2006
    Assignees: Nippon Kensetsu Kikai Shoji Co., Ltd., Asahi Techno Corp.
    Inventors: Yoshiyuki Minamijima, Shigeyoshi Takahashi, Shuichi Matsumura, Toru Yamaguchi