Improved point ball of ball point pens and method of manufacturing same


1,133,995. Ball point pens. SUMITOMO ELECTRIC INDUSTRIES Ltd. 12 Nov., 1965 [21 Nov., 1964; 3 Feb., 1965], No. 48079/65. Heading B6P. [Also in Division C7] A ball for a ball point pen is made of a WC-Co alloy with a C content in the WC of above 5% but below 6À12%, the excess W over that required to form WC being dissolved in the Co preferably to form a # phase. Part of the WC may be replaced by one or more of the carbides of Ta, Ti, Nb, Hf or Zr. In an alternative embodiment balls of normal WC-Co with optional additions of one or more of the carbides of Ta, Nb, Ti, Hf or Zr may be heated in a hydrogen atmosphere at 1000-1300‹ C. while immersed in alumina powder to coat them substantially completely with a layer of # phase. The socket for holding the ball may be of stainless steel, brass or plastics.




Download Full PDF Version (Non-Commercial Use)

Patent Citations (0)

    Publication numberPublication dateAssigneeTitle

NO-Patent Citations (0)


Cited By (6)

    Publication numberPublication dateAssigneeTitle
    EP-0182759-A1May 28, 1986Santrade Ltd.Gesinterte Hartmetallegierung zum Gesteinsbohren und zum Schneiden von Mineralien
    EP-0560212-A1September 15, 1993Sumitomo Electric Industries, LimitedBeschichteter Hartmetallkörper
    EP-0569696-A2November 18, 1993Sumitomo Electric Industries, LimitedCoated cemented carbide member and method of manufacturing the same
    EP-0569696-A3March 08, 1995Sumitomo Electric IndustriesBeschichteter Härtmetallkörper und Verfahren zu ihrer Herstellung.
    US-5503925-AApril 02, 1996Sumitomo Electric Industries, Ltd.Coated cemented carbides
    US-5914181-AJune 22, 1999Sumitomo Electric Industries, Ltd.Coated cemented carbide member