GB107751A - Improvements in or relating to Sound Reproducing Machines. - Google Patents

Abstract

107,751. Compagnie Generale des Etablissements Pathe freres Phonographe et Cinematographe. July 5, 1916, [Convention date]. Tone-arms; tone-arm joints; cases with internal horns; tool-arms and mountings.-The tone-arm of a sound-reproducing machine is so mounted on its socket that it can be removed by lifting. The arm passes loosely through a vertical socket into the horn space, and a ring surrounding the socket supports the tone-arm by means of a bent plate spring. The outer end of the tone-arm, or the sound-box, may be fitted with junction tubes to permit the sound-box to be placed in position for playing vertical-cut or lateral-cut records. The downwardly-bent portion 5 of the tone-arm 1 projects loosely through a socket 8, and its lower curved end is cut off in a vertical plane, so that the sound waves are reflected off a back plate 15 and are amplified in the horn space formed by diverging walls 16 of thin wood. A bent plate spring 6 is secured to the tone-arm 1 and carries a ring 9 which loosely surrounds a flange 4 on the socket 8, the upper face of the flange being inclined. A screw 10 permits the position of the vertical portion 5 of the tone-arm to be adjusted relatively to the ring 9. When a record is being played, the sound-box 2 is slightly lifted by the stylus so that the ring 9 rests on, and turns around, the rear portion of the socket 8. To prevent shaking during transport, the ring 9 may be held down by a detachable screw 13. A rightangle junction tube may be attached either to the end of the tone-arm or to the back of the soundbox, to enable the sound-box to be placed with its diaphragm across or parallel with the tonearm axis, according to the type of record to be played. The Specification, as open to inspection under Sect. 91 (3) (a), describes also a sound-box by which both kinds of record may be played without adjustment, the stylus lever being mounted in a plane perpendicular to the diaphragm but slightly inclined to the vertical. The part 20 is slightly inclined to the diaphragm, and the stylusholder 19 has a greater inclination. This subjectmatter does not appear in the Specification as accepted.