GB469498A - Improvements in or relating to phonographs - Google Patents

Abstract

469,498. Gramophones and the like. PROCTOR, B. A. March 24, 1936, No. 8821. [Class 40 (ii)] A support for a pick-up or the like in a sound - reproducing or recording machine comprises a preferably channel-shaped rigid arm 3, at the outer end of which the pickup 37 or like device is carried, a forked bracket 18 between the branches of which the arm 3 is horizontally pivoted at 21, a bearing member 8 for pivotally supporting at 10 the bracket 18 on a vertical axis, and a vibration-damping weight mounted near the outer end of the arm 3 by means which comprise a resilient member interposed under stress between the weight and the arm. As shown, the vibration-damping weight consists of a pair of discs 30, 31, Fig. 4, mounted on a bolt 32 which passes through a rubber or like sleeve 34 in an opening in the arm 3. Springs 35, 36 coiled on the bolt 32 hold the discs spaced from the arm 3, and their compression may be adjusted to vary the natural period of vibration. Soft rubber sleeves may take the place of the springs 35, 36. The bearings 10, 21 are self-centring ball-bearings. A counterweight 22 is slidably mounted on the arm 3, over a graduated scale 26 which indicates needle pressure. The invention, which is shown for use with a piezo-electric reproducer 37, may provide means for supporting a recorder.