Patents Assigned to Chin-Chih Chuang
  • Drain closure assembly
    Patent number: 3949433
    Abstract: A drain closure assembly including a resilient, dome-shaped plug member which may be changed from stable "closed" convex configuration to a stable "open" concave configuration by applying pressure to either an edge portion or a central portion of the plug member. The plug member is carried by a stem means which in the preferred embodiment is biased upwardly by spring means from a depressed position under the influence of pressure to a stable upper position when the pressure is released.
    Type: Grant
    Filed: June 17, 1975
    Date of Patent: April 13, 1976
    Assignee: Chin-Chih Chuang
    Inventor: Shu-Lien Liou