GB554282A - Improvements in or relating to automatic gramophones - Google Patents

Abstract

554,282. Automatic gramophones. INDUSTRIAKTIEBOLAGET LUXOR. May 19, 1942, No. 6785. Convention date, June 25, 1941. [Class 40 (ii)] In gramophones provided with automatic record-changing devices for records of mixed diameters, the pick-up arm E is arranged to be moved from its outermost position inward over the record to be played a distance at least sufficient to bring the needle 10 over the starting groove of the smallest diameter record (in the form shown slightly further inwards), and means are provided to cause the pick-up arm to be moved back, if it is too far in, until the needle is over the starting groove of the record, whatever the diameter of the record. As shown, a roller 1 is mounted on one end of a spring blade 2 attached at its other end to the pick-up arm by a pivot 3. The roller end of the blade is 'guided in a bayonet-like slot 5 in a plate 6 on the pick-up arm ; and a lever 7 pivoted on a horizontal pivot 8 on the pick-up arm rides at one end on a fixed bar 9 and overlies the spring blade 2 at its other end. During the play of a record, the blade 2 is held by a spring 4 at the upper end of the wide part of the slot 5, Fig. 4, and the roller I is above the surface of the record 12 engaged by the needle 10. When the playing is completed, the pick-up is lifted in known manner and moved outward, and then moved in again to play the next record. The lifting of the pick-up arm causes the lever 7 to be deflected by the bar 9 and to depress the blade 2, which is then moved into the narrow part of the slot 5 by the spring 4, so that when the pick-up arm is again moved in and lowered, the roller 1 touches the record 12 before the needle 10. The axis of the roller is slightly inclined to the radius from the centre of the turntable so that the rotation of the turntable causes the pick-up to be moved outwards until the roller 1 drops over the edge of the record or the turntable. When this occurs, the needle engages the record and play beings. The roller 1 is forced away into the wider part of the slot 5 and is lifted up by the spring 4 back to the position shown in Fig. 4. The records to be played may be stacked on the turntable and discharged therefrom one at a time after being played. The turntable A may be of larger diameter than the records, so that when all the records have been played and discharged, the roller 1 will be engaged by the turntable and impart an extra outward displacement to the pick-up arm. This extra displacement or the resulting drop of the roller 1 over the edge of the turntable is used to actuate a member 14 to apply a brake or to switch off a driving motor. Alternatively, the turntable may have a groove of opposite pitch to the records, so that when no record is present when the pick-up is lowered, the engagement of the needle with this groove causes the pick-up to be moved out and the roller to drop over the edge of turntable.