Patent GB-551392-A (GB)
Title: Improvements relating to automatic stop mechanism for magazine phonographs
IPC: G11B17/16
Filed: 1942-03-11
Abstract: 551,392. Automatic gramophones. GARRARD ENGINEERING & MANUFACTURING CO., Ltd. March 11, 1942, No. 3215. Convention date, March 12,1941. [Class 40 (ii)] A magazine gramophone is stopped automatically when the playing of the last record is completed by means of an improved mechanism comprising a combination of parts including mainly the tripping devices 61 to 68, Fig. 3, controlled by the catch 60 and the cam finger 92 for operating the lever 70 to cause the application of a brake and the switching off of the driving motor. In the arrangement shown, the records to be played are stacked on a shoulder on a central stem 12 and dropped one at a time by means of a reciprocating side pusher 22, Fig. 2, in known manner. A number of leaf springs 14 at the base of the stem retards and silences the fall of the records on to the turntable 11. The stack of records is pressed down by means of an arm 21 hinged to a bracket 20 on a side pillar 18. A spring 52 is connected toggle-fashion between the arm and the pillar so as to hold the arm up when the arm is lifted to place fresh records on the stem, and to press the arm down when the arm is swung down over the records. When the last record is dropped, the arm swings down to the position 21<SP>1</SP> ; and a lug 54 on the arm depresses a sliding rod 56 and swings a lever 57 counterclockwise about its pivot 58, thereby lifting the part 60 of the lever to the position shown in dotted lines away from a lug 61 on a lever 62 pivoted at 63. A follower lever 65 is pivoted at 64 on the lever 62 and is connected by springs 66, 67 to the levers 60, 62. Moreover, the follower lever has a cam-shaped nose 90 adapted to be deflected by a finger 92 on a cam 44, which is itself adapted in known manner to be driven for one revolution to perform record-changing and associated operations after the playing of each record. When the record last played is the last of the stack, the lug 61 is released by the lever 60 as explained above. Then, when the finger 92 deflects the nose 90 after the pick-up arm has been lifted and returned outwards, the counter-clockwise deflection of the follower lever 65 is transmitted by the spring 67 to the lever 62, and the end 68 of the lever 62 turns the lever 70 clockwise about its pivot 71, Fig. 2. This releases the hook-shaped arm 74 of a combined brake and switch lever 75 pivoted at 69 and influenced by a spring 80 extending between the levers 75 and 70. The released lever 75 turns counter-clockwise, applies a brake roller 76 to the turntable, and opens the switch 78 in the circuit of the driving motor 46, Fig. 3. At the same time, a finger 81 on the lever 75 bears on the end 82 of a rod 83 connected to the start-stop lever 84 and this lever is pushed to the "stop" position. A pin 88 on the lever 70 projects into a slot 87 in the rod 83 and rides idly in that slot during the automatic stopping operation just described, but enables the lever 70 to be reset by the lever 84 when this is again moved by hand to the "start" position. The initiation of the rotation of the cam 44 is produced in known manner when the pick-up arm 15 reaches the spiral groove usually provided at the inner end of the record. During play, a lever 31 is gradually moved towards the turntable spindle 35 by the inward movement of the pick-up arm 15, the pivot 32 of the lever 31 being carried by a lever 26 frictioncoupled to a lever 25 connected by an arm 24 to the pick-up arm 15. At each revolution of the turntable spindle 35, an arm 36 thereon in moving past a roller 34 at the end of the lever 31 pushes the lever 26 back over the lever 25, both these levers being pivoted at 28. When the inner spiral groove imparts a quick inward displacement to the lever 31, the arm 36 deflects the lever 31 about its pivot 32 against the action of a spring 33, and the other end 37 of the lever 36 deflects a lever 38 pivoted at 40. The lever 38 in turn deflects a lever 41, Fig. 3, away from a pawl 42 on the cam 44, and this pawl clutches the cam 44 to the driving motor for one revolution.