Patent GB-660566-A (GB)
Title: Phonograph apparatus
IPC: G11B17/16
Filed: 1947-04-30
Abstract: 660,566. Magazine gramophones, PHILCO CORPORATION. April 30, 1947. [May 8, 1946] No. 11563/47. Class 40 (ii). In a magazine gramophone wherein the pick up and the magazine are operated by a cycling cam and the pick up is indexed by either one of two stops according to the size of the batch of records, the stops are controlled by the cycling cam so that they are only in operative position during a record changing cycle. Initiation of change cycle. An arm 15, Fig. 2, secured to the shaft 54 on which the tone arm is pivoted, carries a loose, hanging pawl 42 which towards the end of a record wipes over the threads of a screw 39 mounted on a latch plate 33 which is pivoted about shaft 18. The eccentric terminal groove of the record causes a reverse movement of arm 15 and pawl 42 engages in one of the threads of screw 39 to turn the latch plate 33 clockwise, releasing a spring loaded member 27, Fig. 1, the gear teeth on which then mesh with the continuously rotating gear 26 to initiate rotation of the toothed cycling cam 17. At the end of a cycle, a lug on plate 33 moves member 27 back to the inoperative position and a roller 28 engages a spring detent 20 to hold the cam 17 in its normal starting position. Tone arm actuating mechanism. As the cam 17 rotates, a rise 77 actuates a pivoted arm 43 which, via link 72, applies tension to a spring 71 and a cord 67, Fig. 2, which raises the tone arm about pivot 59 and due to its eccentric arrangement also rotates the tone arm outwards about axis 54 to a position a, a, Fig. 1. A second cam rise 78 now engages a pivoted arm 44 which, via link 75 and spring 73, moves arm 15 and the tone arm outwards beyond the edge of the record to permit another record to be dropped, after which arm 44 encounters a decline on the cam and the tension in link 75 is released. The horizontal force component of cord 67 due to the tension in spring 71 now moves the tone arm inwards to one of the two indexing stops 80, 81. The arm 43 then encounters a decline on the cam 17 which lowers the tone arm on to the record. Tone arm indexing. The tone arm is located by a spring mounted finger 96 on arm 15 which comes into contact either with the 10 inch stop 88 or the 12 inch stop 81. Stop 81 is pivoted on stop 88 and is only operative when an extension 91, Fig. 2, thereon is pressed down by a 12 inch record. Stop 88 is formed by the end of a rod 80, the other end 87, Fig. 1, of which engages the upper surface of cam 17 as so to move the stop into the operative position only during a change cycle. Magazine operation. Records are held between a step 102, Fig. 15, on a stationary spindle 5 and a plate 114 eccentrically mounted on a support 112 by a spring loaded pivot so that the entire upper assembly may be turried manually through 180 degrees to accommodate two sizes of record. Record feed is effected by a sliding ejector plate 115 actuated by a rod 128, bar 131, lever 45 and roller 23 on cam 17. A pivoted arm 135 and a, spring 138 allow bar 131 to overrun if the ejector should jam. Automatic-manual-reject selection. A select tor knob 153, Fig. 1, is connected to a rod 154 which has two locating recesses 155, 156, a portion 157, and a finger 160. In the auto position, as shown, the selector is ineffective. In the forward, manual' position, portion 157 engages member 27 and prevents initiation of the change cycle. In the rearward, 'reject' position, finger 160 trips the latch plate 33 and initiates the change cycle. This is also used to start automatic operation with the tone arm resting on the supporting post 12 which has a 'hook, Fig. 4 (not shown) which engages and restrains the arm until the first record has been dropped on to the turn table. The arm then disengages itself and is moved in to the index stop as above described. Turntable mounting. The rim driven turntable is secured to a tubular assembly 103, Fig. 15, (which also carries the gear 26 drivin,g the cycling cam) and which revolves about the fixed spindle 5 and' is supported by a ball race thrust bearing 107.