Patent GB-334673-A (GB)
Title: Improvements in and relating to sound reproducing machines
IPC: G11B17/00
Filed: 1929-07-26
Abstract: 334,673. Continuous Gramophones, Ltd.., (Oyston, W. R.). July 26, 1929. Multiple machines; returning sound-box to starting point.-A gramophone with a vertical turntable d is provided with means for positioning a record disc upon the turntable, comprising a centering pin g raised automatically in correct relation to the other stages of the operation of the machine and substantially vertically along a diameter of the record disc until it reaches and engages the central aperture o in the latter, whereupon the pin after moving forwardly through the disc continues its vertical movement until it reaches and engages the central aperture d<1> in the turntable. The records are stored in a magazine b and each record is adapted to be rolled by a transfer arm c into a position in front of the turntable d where it is supported on a pair of pads e, e<1>. The central aperture o, o<1> will then be disposed a distance below the central aperture d<1> in the turntable depending upon the diameter of the record. The pin g is carried by a vertical arm f which is pivoted to a horizontal lever h adapted to be rocked on a pivot h<1> by a cam i on the main shaft j of the machine. The vertical arm f is acted upon by a spring k fixed to the lever, h, and its pivotal movement is regulated by stops f<2>, f<3>. When the disc has rolled into place on the pads e, e<1>, the shaft j causes the pin g to contact with the record disc and to move upwardly, engaging the aperture o in the disc in its movement, and finally engaging the aperture d' in the turntable. In this position, a roller l on the cam i engages a cam m pivoted at f<1> on the horizontal lever h. A spring n is connected between the arm f and cam m, and a balancing spring p may be provided between the lever h and shaft j. The shaft j operates after the playing of a record to lower the arm f and disc. The cam i may be formed on a plate i<1> mounted by a screw and slot connection j<2> on a lever jl on the shaft j. The pin g, which may have a frustoconical end with a rounded point, is held in a socket g<1> by a set-screw g<5> which engages a circumferential groove in the pin. The socket g<1> is pivoted at g<2> between the flanges of the channel-shaped arm f, and its pivotal movement is regulated by set-screws g<3>, g<4>. At the conclusion of playing a record, the tone-arm and sound-box are returned by a spring &c. to a position depending on the size of record next to be played and as determined by a stop adjusted by a spindle r which carries two arms s, s<1>, engaging respectively above and below a rail t fitted with adjustable screws t<1> for determining the exact position of the spindle and stop. A thrust rod v is pivoted to a crank u on the spindle r. The upper end v<1> of the rod v is clear of the incoming edge of a record a of smaller size, but is engaged by the edge of a larger disc a<3> so that its lower end v<2> is rocked to engage the side of the arm f. When the arm f moves upwardly, a projection f<4> thereon engages the end v<2>, and the crank u rotates the spindle r to effect adjustment of the stop for the tone-arm and sound-box. At the conclusion of playing the tone-arm moves back to the position for engaging the outermost groove of a smaller size record. Specification 304,070 is referred to.