GB191416602A - Improvements in or relating to Sound Regenerating Machine. - Google Patents

Abstract

16,602. Hopkins, M. C. July 14, 1913, [Convention date]. Sound-boxes; tool arms and mountings; diaphragms. -A talking - machine for either hill - and - dale or s i n u o u s - t r a c k records is constructed with a large conical diaphragm without a sound horn. Fig. 3 is a sectional view of the machine, and Fig. 6 is a larger view of some of the details. The stylus arm is mounted on a plate rocking on knife-edges and having a short arm projecting on either side. The movements of the stylus are conveyed to the diaphragm L by means of parallel rods passing through the tube G, at the rear end of which they are connected to a bell-crank lever which transfers the motion downwards by a rod V in the tube g to a spreading-cap M on the apex of the diaphragm L. The diaphragm has a central cone of more than half the area of the full diaphragm, the surrounding flat annulus being clamped in a heavy mounting carried by the spider J from the lower end of tube g. The tube g is mounted in gimbals to allow of universal motion. The tube G is provided with two heavy cylinders N, N<1> forced apart by springs and surrounded by a sleeve O to prevent contact with the tube ; one of the cylinders is fixed and one free, and both are perforated longitudinally to receive the rods S, S<1> connecting the stylus crosshead Q to the bell-crank cross-head R. The vertical rod V connecting the cross-head to the diaphragm is notched at v to allow for the slight angular motion of the arm U of the bellcrank cross-head R. The stylus cross-head Q is set either vertically or horizontally, according to the type of record in use.