Patent GB-501165-A (GB)
Title: Improvements in or relating to automatic record-changing phonographs
IPC: G11B17/16
Filed: 1937-12-06
Abstract: 501,165. Magazine gramophones. ALM, K. M. Dec. 6, 1937, No. 33709. Convention date, Dec. 9, 1936. [Class 40 (ii)] Relates to magazine gramophones of the kind in which a record when in playing position is suspended rotatably in such a manner that both sides are accessible for reproduction without the record being turned over. According to the invention, gripping means are adapted to extend into the central hole in the record, for holding the record exclusively by firm pressure of the gripping means against the wall of the hole, there being no engagement with the lower surface of the record. As shown in Figs. 2 and 7 unplayed records 51 are stored in a pile on a base 120, being centred by a pin 53, frictionally supported in a sleeve 54. One record G is shown in Fig. 2, suspended in position for playing, to which it has been transferred from the pile at 51 by means of a swinging arm 6 on which is the gripping device 7 as well as a driving motor 5. The motor is geared to a wheel 9, Fig. 4, secured to a sleeve 8b which is rotatably mounted on the arm 6. The sleeve is connected by a screw 8a &c. to a tubular shaft 8, carrying a disc 22 formed with teeth or the like 23. Within the shaft 8 is slidably fitted a tube 10 having at its lower end a number of resilient flaps 11a, ridged, or roughened externally. A rod 12, having a pin f3 and a tapered head 12a at its lower portion, is slidable in the tube 10. Springs 18, 19, arranged as shown, act respectively on the rod 12 and the tube 10, being normally held compressed by a spring-controlled detent 16. This member is adapted to be rocked outwardly about its pivot 17 by means of a ring 113, Fig. 8, as described below, so as to release in turn the parts 12, 10 and allow them to be moved upwardly by their springs 18, 19. The arm 6 is attached to an L-shaped rod 26 which is mounted by means of rollers 27 so as to be slidable up and down a vertical column 28, forming part of a framework which also comprises a vertical rod 30 for guiding the arm 6 and which is adapted to be swung around bearings 29. The necessary movements of the arm 6 for transferring a record are effected by levers 34 and 39, actuated by cams 38, 43 on an intermittently-rotated shaft 40 driven by a motor 44 ; the lever 34 causes the raising and lowering of the arm, and the lever 39, coupled by a link 36 to the rod 30, effects the swinging movement. Two pick-ups (not shown) are preferably provided to engage in turn with the upper and lower sides of the record respectively when the -record is in the playing position. The pick-up arms may be pivoted on separate sleeves mounted on a common vertical spindle, and adapted to swing independently of each other, Fig. 6 (not shown). Instead of this arrangement, a single pick-up may be adapted to. engage each side of the record in turn. The operation of the machine is as follows. To pick up the top record from the pile 51, the arm is swung by moans of the cam 43 and members 39, 36 to a position over the pin 53, and is lowered by the action of the cam 38 and lever 34 until, as shown in Fig. 7, the pin 13 enters a recess in the centring pin 53 and the latter is pushed down by the rod 10 sufficiently to clear the hole in the top record, the upper surface of which is then engaged by the disc 22. When this has occurred, further movement of the lever 34 causes levers 101, 101 to rock, Fig. 8, and to press the ring 113 down against the detent 16, shifting it aside, and releasing in turn the members 12, 10 of the gripping device. The Raps 11a are thereupon expanded by the head 12a, Figs. 4 and 7, into firm engagement with the wall of the hole in the top record, and the subsequent slight upward movement of the rod 10 causes the record to be pressed against the teeth or friction layer on the disc 22. The arm 6 then rises, and is swung to bring the record to the playing position, during which swinging movement the motor 5 may be operating to rotate the record. Both sides of the record are played in turn, and in the machine described, in which two pick-ups are provided, the record is first moved downwards from an intermediate position to engage the lower pick-up and afterwards upwardly to engage the upper pick-up. The necessary automatic swinging movements of the pick-up arms are effected in any known manner. and means (not described) are provided for reversing the direction of rotation of the record before the second side is played. During the vertical movements of the arm 6, before it is finally restored to the intermediate position in readiness for return to position over the unplayed records, a lever 121, Fig. 8, is automatically shifted, and, when both sides of the record have been played, is caused to press down the rod 12 so that the record is released and falls down to a storage position 52, the parts of the gripping device being at the same time reset to their normal position preparatory to the picking-up of a fresh record. Specification 438,658 is referred to.