Patents Assigned to Kojima Plastics Co., Ltd.
  • Patent number: 9533442
    Abstract: Providing an injection mold used for producing a molded resin article which is free of a weld line, irrespective of an injection pressure of a molten resin. At least one protrusion is provided in a first region of a ring runner portion defined by an inner circumferential surface of a first communication hole extending toward a cavity and an outer circumferential surface of a pin member disposed coaxially within the first communication hole, such that the protrusion projects from either one of these surfaces and an end face of the protrusion is held in contact with the other of these surfaces. The first region is a half of a circumference of the ring runner portion and is opposite to a circumferential position at which the first communication hole and a second communication hole extending perpendicularly to the first communication hole communicate with each other, with respect to the pin member.
    Type: Grant
    Filed: December 23, 2014
    Date of Patent: January 3, 2017
    Assignee: Kojima Plastics Co., Ltd.
    Inventors: Makoto Yokota, Chihiro Hayashi, Kazuhiko Tajiri, Yusuke Hiroi