Patent GB-630125-A (GB)
Title: Improvements in or relating to multiple record playing gramophones
IPC: G11B17/02
Filed: 1945-03-17
Abstract: 630,125. Magazine gramophones. KATZ, L. NAMENYI-. March 17, 1945, No. 3151. [Class 40 (ii)] In a magazine gramophone, each record is carried by an individual turntable provided with a mounting movable from a position in which the record is aligned with the others, to a playing position in which it is at least partly clear of the others, and means are provided for establishing a drive between a single driving motor and each record when the record is brought to the playing position, and for bringing a pick-up into or out of playing relationship with the driven record. Two pick-ups are provided for the playing of the upper and lower sides respectively of the records. Control knobs (one per record) mounted one above the other on a side wall of the cabinet, control the movement of the turntables 12, each mounted on a swinging arm 13 (Fig. 1). A motor 9 and gear-box 15 (Fig. 2) are fitted at the base of the cabinet and drive two upwardly extending screw-threaded shafts 16 and a square-sectioned shaft 17. The shafts 16 engage threaded bushes (not shown) on a platform 19 (Figs. 1, 2), thus serving to raise or lower it. This platform carries the record-driving mechanism 20 (Fig. 1) and the traversing-mechanisms 21 for pick-ups 22 and 23 (Fig. 2). The end of each arm 13 has a spindle 24 (Fig. 4) mounted thereon carrying a ball cage 26 and spring clip 32 which clamps the record against the rim 28 of the turntable. The swinging arms 13 are individually mounted pivotally on an upright shaft 42 (Figs. 1, 2) and are spaced apart by collars 43. Each arm has a rounded nose-portion 44 on the opposite side of the shaft 42 to the turntable. When the turntables are in the non-playing. position, all these nose-pieces are in line and may be traversed from top to bottom by the fork 45 formed at the end of the armature 46 of a solenoid 47 mounted on the platform 19. The armature is constrained to move rectilinearly by the engagement of two pins 49 fixed to the platform with the slot 48 in the armature, and is spring-urged away from the solenoid 47. As the solenoid is normally energized the fork 45 traverses the nose-pieces 44 until the platform reaches the position of one of the operated control knobs whereupon the solenoid is deenergized and the spring 52 causes the fork to move the nose-piece 44 to the left (Fig. 1) and bring the selected record into the playing position. Slidably mounted upon the squaresectioned shaft 17 is a double driving pulley 53, 54 (Fig. 5) located between bosses 55, 56 below the platform 19. An idler double pulley 58, 59 is also provided and is driven by a belt 60 encircling pulleys 53, 58. Extending transversely between the other pulleys 54, 59 are the two stretches 61, 62 of another endless belt which encircles a pulley 63 (Fig. 1) associated with the roller 40 which provides rim drive to a record in the playing position, and a pulley 66 mounted to rotate about the pin 65 on the platform. The pulley 63 and roller 40 are rotatably mounted on an arm 64 pivoted about the pin 65. Thus, when the arm 64 is at one limit of its movement the stretch 62 engages pulley 54, whereas at the other limit the stretch 61 engages pulley 59 which is of smaller diameter than 54. The former position is effective when playing a 12-inch record (full lines, Fig. 1), and the latter for a 10-inch record (chain-dotted lines, Fig. 1). The driving roller 40 is driven by the belt 61, 62 at the speed appropriate to the record diameter in each case. Each of the pick-ups is mounted on a carriage 70 (Fig. 2), the rollers 71 of which run along a guide-rod 72. Each carriage may swing about the corresponding rod 72, both being gravity-urged to a position in which the pick-up engages the record, the engagement of the needle with the record-track controlling the tracking of the pick-up. An endless belt 74 (Fig. 1) encircles two pulleys 75, 76 which are mounted on the rod 72 and which may be swung about the rod by the operation of solenoid 82 (Fig. 2) when the pick-up reaches the end of a record, so that the belt is driven by the roller train 39, 181 (Fig. 1), and engages a lever arm 3 (Fig. 2) on the pick-up. This swings the pick-up away from the record and returns it to its starting point. Operation. Starting with the pick-ups returned to their starting points but with a played record still in playing position, operation of the starting switch energizes solenoids 47 and 82, and the record and the pick-up are withdrawn from their playing positions. The motor circuit is completed and the platform is driven to the nearest operated control knob, whereupon the solenoids 47 and 82 are dedenergized. The selected record swings into the playing position and the pick-up is lowered onto the record. The record is played and when the pick-up has returned to its initial position under control of solenoid 82, solenoid 47 is again energized and the record returns to the non-playing position. If it is desired to play both sides of the selected record the control knob is set so that the contacts controlling the return of the record to the non-playing position are inoperative. An electromagnetic one-revolution clutch and reversing gear control the up-and-down motion of the platform 19 under the control of the selected control knob. The pick-up to be used and the direction of rotation of the record to be played are also controlled by the manner in which the control knob is operated. The knob has settings for playing the top, or bottom side only, or both sides in succession. The Specification gives full particulars of the detailed circuit arrangements which effect the various controls.