Improvements in or relating to the manufacture of needles for gramophones or the like sound-reproducing or sound-recording apparatus

摘要

394,823. Gramophone needles. JORDAN, J. F., Trelawney, Clapham, near Worthing, Sussex. July 25, 1932, No. 20968. [Class 40 (ii).] Needles for gramophones and the like are made of burnt clay, preferably by drying to a plastic condition a colloidal suspension obtained by washing out the coarser ingredients, drying further, and heating to a sintering temperature for about ten to twelve hours. An analysis of a kind of clay suitable for the purpose is given. The needles may be of various shapes, two examples being shown. A metal or rubber band 11 may be provided near the end that is to be gripped by the clamping screw, to prevent fracture.