Patent GB-216572-A (GB)
Title: Improvements in or relating to talking machines
IPC: G11B17/16
Filed: 1923-02-28
Abstract: 216,572. Stout, J. E. Feb. 28, 1923. Multiple machines; turntables; returning sound-box to starting-point. - In a magazine gramophone, the turntable is movable vertically in axial alignment with a pile of records, to receive the records successively for playing, and to restore the whole of them to the position in which they are normally stored after the complete series has been played. The records are initially supported, above the level of the tonearm, on a set of latches 30, pivoted in three posts 45 arranged around the turntable 2. The latter is fixed to a spindle 3 which passes freely through a hub 5, its lower end resting in a thrust bearing 8. Rotation of the turntable occurs when it is in frictional contact with the hub 5 (pressure being maintained by a spring 6), the hub being driven through long teeth 5a gearing with a worm 7 on a motor-driven spindle 70, Figs. 1 and 5. The worm 7 also gears with a wheel 11, which is adapted to drive, through a clutch 12, a spindle 13 which operate two cams 10, 21. The cam 10 effects the raising and lowering of the turntable, and the cam 21 brings about the return of the tone-arm from the finishing to the starting- point. The clutch 12 is normally inoperative but is thrown into action automatically at the end of the playing of a record. This effect is produced by the release of a detent, when a member engaging therewith and traversed by a motordriven screw moves away from the. support afforded by another part controlled by the tonearm. When the spindle 13 is thus clutched in and driven, the cam 21 moves back the tone-arm to a position beyond the starting-point, by acting on a lever 87 engaging with an arm 54 on the tone-arm, Fig. 5. The final placing of the sound-box needle over the starting-point of a new record is brought about by a spring-actuated lever 93, coacting with an adjustable stop 96. The spindle 13 is de-clutched automatically after one revolution. The cam 10 engages with a pin 9 projecting from the bearing 8 which supports the turntable-spindle 3, and it has a slot-and-key connection with the spindle 13 so that it can rise and fall. A spring 17 tends to raise the cam, and a slidable pawl 18 normally locks the post 16 on which the cam is supported. During the first part of the revolution of the cam 10, it allows the turntable to fall sufficiently to clear the sound-box; then, when the tone-arm has been returned by the cam 21, a member 112 operated by the cam 10 pushes back the pawl 18 and frees the post 16, whereupon the cam is lifted by the spring 17 and raises the turntable and the records thereon. The rotating cam 10, bearing against the pin 9, continues the raising of the turntable to take a new record from the store on the latches 30, as subsequently described, or, if the last record of the series has just been played, to restore the whole pile to another position on the latches. During the last part of the revolution of the cam 10, the turntable is allowed to fall below the level of the sound-box, and finally, the turntable is raised again a little, so that if a new record has been taken on it is brought gently into contact with the needle. The record-releasing mechanism within each of the posts 45 comprises a spring-pressed lever 31 carrying at its upper end a finger 35 controlled by a spring 31<a> and a set-screw 37, the lever coacting, through a pin 32, with a member 38 mounted within and on the same pivot 40 as the latch 30. A spring 33, stronger than the spring 34, normally presses the latch 30 forward.. The arrangement is such that as the turntable rises, its edge presses back the latches 30, 38, and the fingers 35 are protruded so that they enter between the bottom record in the pile and those above it. Further upward movement of the turntable is thus prevented, and the rotating cam 10 is depressed through a distance depending upon the number of records then upon the turntable; the pawl 18 holds the post 16 when the cam has been thus pushed down, and so the elevation of the turntable when playing the next record is determined. Upon the descent of the turntable, after the above-described protrusion of the fingers 35, the fingers recede, the released record is taken down with the turntable, and the remaining records are retained by the latches 30. Means are provided whereby, when all the records have been released, and the turntable rises with them on it after the playing of the last one, the fingers 35 are prevented from advancing. Consequently, the latches 38 are not pushed back when the turntable engages the hollow latches 30, and support the whole pile of records after it has been moved upwardly beyond them.