GB472135A - Improvements in magazine gramophones - Google Patents

Abstract

472,135. Magazine gramophones. MANN, G. S. July 2, 1936, No. 18360. [Class 40 (ii)] The spring-loaded turntable 10 and magazine platform 4 of an automatic gramophone are interconnected by an adjustable pivoted lever 17, 17a, and after a record has been transferred from the magazine to the turntable, a clutch is released to allow the turntable to descend under the weight of the records thereon by an amount equal to the thickness of a record, the movement being limited by the top record in the magazine coming into contact with stop members 78 carried at the end of a pivoted lever 77. The records are transferred by an angularly-movable arm 19 which carries at its free end an electromagnet 20, the records having iron or steel centres or being provided with loose iron or steel discs as described in Specification 403,786, in order that they may be lifted by the said magnet. When the stylus reaches the run-off groove of a record, the horizontal oscillation of the tonearm operates an electric switch 49, Fig. 7 (sectional plan on line VIIVII, Fig. 5), which switch energizes an electromagnet 24, to cause a pinion 27 carried by an arm 26 to engage a pinion 29 on the base of the turntable well 11. The rotational movement of the turntable is transmitted through a wheel train and connecting rod 36 to a lostmotion plate 38 mounted on the spindle 23 of the record-transferring arm. A horizontal spring-loaded rod 58 engages in a notch 57 in the edge of the lost-motion plate, the initial rotation of which causes a projection 64 on the rod 58 to open the switch 49, and simultaneously closes a duplex switch operated by a projection 65 on the plate 38, by which the energization of the magnet 24 is maintained and that of the magnet 20 initiated. At the same time the end of the rod 58 engages with a bell crank lever 59 by which the tone-arm is raised. The record to be transferred to the turntable is lifted during the interval between the energization of the magnet 20 and the engagement of a projection 42 on the plate 38 with a radial projection 41 on the transfer-arm spindle, and the subsequent motion of the arm 19 causes the tone-arm to be swung outwardly in to its correct position for engagement with the record transferred from the magazine. The energization of the magnet 20 is accompanied by the pivoting of the lever 77 about a pin 79, whereby the stop members 78 are raised to permit the top record in the magazine to be lifted by the magnet 20, after the magazine platform 4 has been locked in position by the engagement of the end 92 of a pivoted spring-loaded lever 90 with the sleeve 5, the lever being actuated by a pin 96 on the lost-motion plate 38 which engages with a cam-shaped portion 95 at the end of the lever. When the record is in position over the turntable the magnet 20 is de-energized by an auxiliary switch operated by the lost-motion plate and the record deposited on the turntable. The return of the plate 38 to its initial position carries the transfer arm back to its position over the magazine, the magnet 24 is de-energized, the duplex switch opened, the magazine stop .78 is lowered and the clutch 92 released to allow the magazine to rise and the turntable to be depressed a distance equal to the thickness of the record deposited on the turntable. The push-rod 58 re-engages with the notch 57 in the lost-motion plate, being accompanied by rotation of the bell-crank lever 59 and the lowering of the tone-arm to bring the stylus into engagement with the record. The turntable 10 is driven by an electric motor 16 through worm gearing, the turntable spindle sleeve 12 being slidably keyed to the worm wheel 15, which latter is prevented from vertical movement, in order that the table may be driven when in any position. Specification 402,779 also is referred to.