Patents Assigned to 501 Mitsubishi Shindoh Co., Ltd.
  • Heat transfer tubes and method for manufacturing
    Patent number: 5052476
    Abstract: A heat transfer tube having an inner surface in which are formed primary grooves and secondary grooves. The primary grooves parallel to one another, extending at an angle to the longitudinal direction of the heat transfer tube and secondary grooves parallel to one another, extending an angle to the primary grooves. At the intersections of the primary and secondary grooves is formed a series of pear-shaped grooves whose inner opening dimension is smaller than the dimension of the bottom of the pear-shaped groove.
    Type: Grant
    Filed: August 28, 1990
    Date of Patent: October 1, 1991
    Assignee: 501 Mitsubishi Shindoh Co., Ltd.
    Inventors: Shunroku Sukumoda, Seizo Masukawa, Haruo Kohno