Patents by Inventor Humiharu Machi

Humiharu Machi 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).

  • Method of stopping leakage of water in concrete structure
    Patent number: 4758295
    Abstract: A method of stopping leakage of water in a concrete structure comprising injecting a hydrophilic one component type polyurethane prepolymer or an impregnating agent which is prepared by adding cement to such polyurethane prepolymer into a hermetically sealed chamber formed in a leaking part of the concrete structure, whereby the polyurethane prepolymer foams and cures through reaction with water leaking in the concrete structure and the foamed prepolymer is forced to enter all cracks in the leaking part of the concrete structure by means of foaming pressure and volume expansion caused by the reaction, thereby caulking and hermetically sealing the cracks, and thus restoring the strength and watertightness of the concrete structure.
    Type: Grant
    Filed: April 3, 1987
    Date of Patent: July 19, 1988
    Assignee: Shimizu Construction Co., Ltd.
    Inventors: Minoru Sawaide, Hiroshi Miura, Humiharu Machi, Shigeo Shimizu