Patents Assigned to Platinum Pen of America
  • Patent number: 4573817
    Abstract: A mechanical pencil having a cylindrical barrel (1) and a sheath (2) in axial relationship is disclosed. A spiral member (4) in fixed relationship with the sheath and in axially sliding relationship with the barrel for a predetermined range engages a slider (7). The slider is in fixed relationship with a push feed type writing unit and slides axially within a predetermined range within the barrel (1) as allowed by a guide (3). First spring means is provided to urge the spiral member in a forward direction when the writing unit is positioned axially such that it is contained within the barrel (1). As the writing unit is moved from its rearmost position within the barrel (1) to a protruding position by rotation of the spiral member (4), a second spring means urges the spiral member in a rearward direction, forming a gap between the barrel (1) and the sheath (2).
    Type: Grant
    Filed: May 8, 1981
    Date of Patent: March 4, 1986
    Assignee: Platinum Pen of America, Inc.
    Inventors: Mitsuo Maki, Tomohiro Hosoo, Katsuyoshi Kikukawa
  • Patent number: D278157
    Type: Grant
    Filed: May 8, 1981
    Date of Patent: March 26, 1985
    Assignee: Platinum Pen of America
    Inventors: Mitsuo Maki, Tomohiro Hosoo, Katsuyoshi Kikukawa