| 摘要 |
864,523. Automatic gramophones. BIRMINGHAM SOUND REPRODUCERS Ltd. July 9, 1957 [May 29, 1956], No. 16607/56. Class 40 (2). Means to initiate drive of a gap wheel 7, when the pick-up of an automatic recordchanger enters the run-out groove, comprises two frictionally-coupled elements mounted thereon (e.g. plates 11, 12 pivoted at 13); one of these, 11, is moved in one direction by the tone-arm 3 during reproduction and subsequent run-out, and returned by a part rotating with the turntable pinion 9 (e.g. by its actual teeth, or by a separate cam) when the gap wheel 7 is driven thereby; the other, 12, has a part 19 engaged by eccentric means (such as an extended tooth 22) rotatable with the pinion 9, to cancel its slow advance during reproduction, Fig. 12, but to pick up a drive during run-out, Fig. 13, sufficient to bring the gap wheel 7 and pinion 9 into mesh. A lug 20 on the plate 12 passes through a notch 18 in the plate 11 to a slot 21 in the wheel 7, whereby the movements of the plates 11, 12 are positively limited, the lostmotion between parts 20, 18 allowing for the cancellation of the slow advance of the plate 12. As shown, the inward motion of the tone-arm 3 is conveyed to the plate 11 by an arm 24 engaging a bar 26 longitudinally slidable beneath the deck 1, the inner end of the bar having a V-shaped lug 28, the tip of which, in the idle position of the gap wheel 7, contacts a pin 14 projecting from the plate 11 through a slot in the wheel 7. After the tone-arm 3 has been swung outwards during the automatic cycle, a pin projecting beneath the wheel 7 engages a side of the V-shaped lug 28 to restore the bar 26, and the teeth of the pinion 9 engaging an inclined edge 17 of the plate 11 progressively restore the latter, which by engagement of the notch 18 with the lug 20, retracts the part 19 from the path of the tooth 22.
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