GB1110590A - Automatic gramophone turntable - Google Patents

Abstract

1,110,590. Record changers. H. EBNER [trading as PERPETUUM-EBNER FABRIK FœR FEINMECHANIK und ELEKTROTECHNIK STEIDINGER & CO. KOMM. GES.]. 8 Nov., 1965 [26 Nov., 1964], No. 47214/65. Heading G5R. An automatic record changing gramophone having a cam for controlling the traverse and vertical movements of the pick-up arm, is provided with a manually operated selector lever which in one position precludes automatic traverse of the pick-up arm so that it may be manually traversed. Movement of the selector lever to a second position then causes automatic lowering of the pick-up arm in the usual manner. Manual traverse and automatic lowering of the pick-up arm in this manner may be effected only when playing single records. In this case movement of the selector lever to the two positions in question is prevented during automatic record changing operation by insertion of the removable spindle which carries the record stack. As disclosed, the selector lever has five positions (1) rest position 0, (2) start, (3) stop, (4) manual position I, (5) manual position II. When the selector lever 17 is moved from the rest to the start position, Fig. 2(b) a pin 19 thereon passes from rest notch 20 to start notch 24 in a spring biased stop'lever 21 which is thereby momentarily rocked and rocks a recoil lever 26 on the cam 15 so that this lever is engaged by a cam plate 27 rotating with the turntable to turn the cam 15 sufficiently for its geared rim 28 to engage the drive pinion 29 rigid with the cam 27. The continued rotation of the cam 15 by pinion 29 now effects in known manner, dropping of a record from a stack and control of the pick-up arm. Stop position. Movement of lever 17 into this position, Fig. 2(c), momentarily rocks the stop lever 21 again to initiate rotation of the cam 15 and also displaces a guide member 35 on the cam 15 through a lever 30, which, after the pick-up arm has been lifted and swung to its outward position automatically, constrains a follower pin 36 to move in a concentric track 37 in the cam 15 so that inward movement of the pick-up arm via the tracking lever 14 is precluded and it comes to rest on its support 38. Manual positions I, II. When the selector lever 17 is moved from the rest position 0, to the position I, Fig. 2(d) the stop lever 21 is again momentarily rocked, as for the start position, to initiate drive of the cam 15. In addition, the lever 30 is rocked so that its end 40 moves a pivotal guide member 42 which constrains the follower pin 36 on the tracking lever 14 to move in the circular concentric groove 43 in the cam 15 thus preventing automatic traverse movement of the pick-up arm 7 (which is normally effected by the follower pin 36 moving in an eccentric groove in cam 15 thereby rocking the tracking lever 14 which traverses the pick-up arm through a friction clutch 13). Subsequently, a surface 44 of lever 30 engages a cam element 45 on and thereby rocks a toothed segment 47 inwardly to interrupt the gear rim 28. The cam 15 is thus stopped when the tooth gap arrives at the drive pinion 29 with the pick-up arm in its lifted position. The lift of the pick-up arm is, however, made less than during normal automatic control by a limiter lever 48 surrounding the lifting stud 12 and actuated by the selector lever 17. After the pick-up arm has been traversed manually, as desired the selector lever 17 is moved to position II. Thereby the stop lever 21 is again displaced, Fig. 2e, but this time engages the lobe 45a of the toothed segment 47 whereby the latter is again inserted in the gap of the gear rim 28 so that the cam 15 is now driven into its rest position, Fig. 2a (not shown), during which time the pick-up arm is automatically lowered on to the record and an element 51 on cam 15 rocks the stop lever 21 to restore the selector lever 17 to the rest position 0 under spring control.