Patent GB-422586-A (GB)
Title: Automatic record changing mechanism for gramophones
IPC: G11B17/00
Filed: 1933-10-18
Abstract: 422,586. Magazine gramophones. SMALL, T. W., 2706, East Drive, Fort Wayne, Indiana, U.S.A. Oct. 18, 1933, No. 28880. Convention date, Aug. 30. [Class 40 (ii)] A gramophone having automatic recording-changing mechanism has a record magazine adapted to be inverted about a transverse diametral axis between the reception of a played record on the top and the delivery of a fresh one from the opposite face and to lie substantially in the plane of the turntable during the transfer of a record. The changing of the records and resetting of the pick-up are effected by one revolution of a shaft 19, Figs. 3 and 4, which is driven by an electromagnetically released spring - engaged dog-clutch 18 and a shaft 15 flexibly coupled to a second shaft 14 driven by the motor 11. The clutch-holding latch 28 is carried by a spring-controlled shaft 29, Figs. 4 and 5, and is freed by the withdrawal of the stop 34 on closing the electromagnetic circuit at the points 121, Fig. 1. The contacts 121 are made by an arm 116 frictionally driven by a leather washer 115, Fig. 6, resting on a boss of the pick-up spindle. The circuit is broken by a spur on the shaft 29 at the switch 124, Fig. 7. The pick-up is raised for the record-changing operation by a cam 50, lever 52 and a plunger 55 acting on the pick-up arm 41, Figs. 2 and 6, and is positioned for playing the next record by a projection 61 on a link 60 and a lever 45 on the pick-up spindle, the link 60 being moved longitudinally by arms 58 thereon and a cam 57 keyed to the shaft 19. A spring stop 63 determines the starting position of the pick-up. The link 60 also actuates the record shifting arms 87 and 92 by cranks 94 and 95. The record magazine consists of a semicircular band having lugs 67, 68 and a bridge-piece 66 mounted over an opening in the deck plate 10 on pivots 70. The rotation of the magazine is effected by cams 72, 73, lever 76 and link 79 from a shaft 81, Fig. 2, the shaft 81 being reciprocated by links 83 connected to cranks on the shaft 19, Fig. 3. The played record is raised by a cam 100 on the shaft 81 and a lever 102 connected to a cross-bar 105 having adjustable ends engaging the stems of the record-supporting members 97, Fig. 4. The record is then moved along guides 108 by the projecting end 88 of the arm 87 and received on the side A of the now horizontal magazine. The arm 92 during this operation is carried over the magazine by a guide 93 being pivoted on a cross-pin 91 for this movement. On receiving a record the magazine is rotated to bring the opposite side B above and on the return movement of the arm 92 a record is engaged by the projections 110 and 112 and moved thereby over the platform and then lowered by the supports 97. An opening 111 in the magazine permits the passage of the projection 112 to engage the record and a fixed stop 130 on the deck-plate 10 prevents more than one record being delivered from the magazine. The pick-up arm is pivoted in a yoke 40 and balanced by springs 46 acting on a cross-piece adjustably secured on a supporting pin 49, Fig. 6. After one rotation of the shaft 19 the clutch is disengaged by a cam 26<a> which depresses the cam-shaped stop 28 into the path of the pin 27 of the clutch member and allows re-engagement of the spring-pressed stop 34. The arm 116 is prevented from making contact by a projection 119 on the platform until the quick centring movement of the pick-up arm moves it inwardly before a revolution of the projection 119 is completed.