Patent GB-568917-A (GB)
Title: Improvements in automatic phonographs
IPC: G11B17/16
Filed: 1943-05-25
Abstract: 568,917. Automatic gramophones. FARNSWORTH TELEVISION & RADIO CORPORATION. May 25, 1943, No. 8336. Convention date, May 15, 1942. [Class 40 (ii)] An automatic gramophone comprises a turntable 34 supporting a stack of records 35 to be played, diametrically opposite mechanisms 110 for engaging the edge of the topmost record and slightly raising the record. and a gripping device 148, 149 for gripping the edge of the slightly raised record and lifting up the record to reverse it and replace it or to discharge it into a receptacle 175. General operation. The turntable 34, Fig. 2, supporting the stack of records 35 to be played is mounted on ball bearings 20 supported by a sleeve 18, which can be raised and lowered by a worm gear 39 driven through mitre gear 43, 44. When the records are piled on the turntable, the gearing is driven by a knob 66, Fig. 19, at the side of the gramophone to lower the turntable to an extent corresponding to the numof records to bring the top record down to the playing level. The knob 66 drives the mitre gear 44 through pinions 67A, 72B, 72A, 61A, shaft 61, and spur gearing 64, 65, Fig. 2. A pointer 67 on the knob moves over a dial 68 indicating the number of records for which the knob is set. When one side of the top record has been played, the pick-up arm is lifted and moved out, and the top record is lifted by two pairs of fingers 111, 112, one pair on each side. Each pair of fingers is mounted between spring washers 115, 116 on a vertical spindle 107. To lift the record, the spindles are first turned to make the fingers 112 pass over the edge of the record and thereby to guide the fingers 111 to enter between the top record and the next below. The fingers are long enough to do this whether the records 35 are of 10 or 12-inch diameter, mixed or not. Then the spindles are lifted to raise the top record above the others. After this, a pair of grippers 148, 149, Fig. 3, are made to grip the raised record and to lift the record to the inclined position A. There the record is turned through 180 degrees, and after this the record is brought down again on the fingers 111. Finally, the fingers 111, 112 are lowered and turned back to their original position, and the record is now in position for its second side to be played. When this side has been played, the same operations are repeated, except that the record is now swung further by the grippers 148, 149 and dropped by these grippers into a played-records receptacle 175, Fig. 3, comprising an inclined back plate 176, a pair of record supporting pins 177 and a pair of recordguiding wings 178. The cycle is now completed by the turntable being raised a distance equal to the thickness of a record, to bring the record now at the top to the playing level. This is performed by driving the mitre gear 44 through a clutch 49, 50 by the shaft 27, the rotation of which performs all the automatic operations. Automatic mechanism. The automatic operations are initiated in known manner, as described in U.S.A. Specification 2,018,881, when the pick-up reaches the quick-pitch groove at the inner end of the record. This causes the closing of the circuit of a solenoid 31, Fig. 2, which sucks its core 30 up, thereby lifting a lever 29, bringing a clutch member 23 in engagement with a clutch member 24. The clutch member 23 is feathered to the turntable shaft 21 which surrounds a central fixed stem 36. When the clutch is engaged, rotation is transmitted through a worm 25, fast with the clutch member 24, to a worm wheel 26 on a transverse shaft 27, which carries a number of oams and makes one revolution to perform the several automatic functions. Pick-up mechanism. The pick-up arm 75, Fig. 15, is pivoted at 83 on an arm 85 on a hollow spindle 86. A rod 89 extends through this spindle from a cam 92 below to an arm 84 above. This arm is pivoted at 83, and its front end engages below one end of a lever 80 pivoted on the pick-up arm, the other end of the lever having a pin 81. This end of the lever is normally held raised by a spring 82. The lower end of the hollow spindle 86 is fitted with an arm 87 co-operating with a spring 88 and the cam 92 to control the movements and positions of the pick-up. The shaft 90 of the cam 92 is fast with an arm 98, the end of which has a pin .100 urged by a spring against a face cam 102 on the shaft 27. When this shaft makes one revolution to perform the automatic operations, the cam 92 is first turned in one direction. It lifts the rod 89 thereby depressing the pin 81 and lifting the pick-up. A finger 94 on the cam releases the spring 88 to permit the end of the spring to come in the path of the arm 87. Another pin 95 on the cam engages the arm 87 and thereby turns the pickup arm outwards. After the record reversing or changing operation has been performed, the cam 92 is turned back, the pin 95 allows the spring 88 to turn the pick-up back until the pin 81 is stopped by the edge of the record on the turntable. This positions the pick-up over the starting groove of the record whether the record is a 10-inch or a 12-inch record. Then the pick-up is lowered for the next playing operation. The movements of each spindle 107, Fig. 2, for raising and lowering the topmost record is performed by cam members 104, 121 co-operating with each other under the influence of a spring 109. The spring 109 acts on the spindle 107 both longitudinally and rotationally, tending always to hold the spindly down and to turn the fingers 111, 112 to the inoperative outward position. The cam member 104 is fast with the spindle 107, and the cam member 121 is coupled by flexible bands 97 to the cam 92, Fig. 15, of the pick-up mechanism; so that, like the cam 92, the cam member 121 is first turned in one direction at the beginning of an automatic, cycle, and in the reverse direction at the end of the cycle, this manner of operation being controlled by the cam 102 of the transverse shaft 27 which makes one revolution to perform the automatic operations. The grippers 148, 149, Figs. 1, 3 and 5, for lifting and reversing or discharging the top record are in the form of levers pivoted at 150, 151 on toothed sectors 144,145 pivoted at 146, 147 in a housing 135, in which is journalled a shaft 154, having at one end a bevel pinion 155 in mesh with the sectors 144, 145, and at the other end another bevel pinion 156. The housing 135 is rotatably mounted about the axis of the shaft 154 between segmental pro. jections 137 on members 132 mounted between pivots 131 on a fixed bracket 130. In the normal rest position, the housing 135 is horizontal and the grippers are swung out in opposite directions as shown in Fig. 1. A rotation of the shaft 154 in one direction is adapted to swing the grippers about the pivots 146, 147 towards each other and over and under the edge of a raised record. When the grippers overlap, cams 148B, 149B on their tails ride over each other and cause the grippers to turn in opposite directions about the pivots 150, 151 to grip the record firmly between their padded ends 148A, 149A. The several movements of the housing 135 are operated from the shaft 27, Figs. 2 and 4, under control of a cam 192 on that shaft. This cam has a track 193 with branches 194, 197 bridged by two paths 195, 196 with a pivoted gate 199A to determine which of these two branches shall operate. The position of rest is shown in Fig. 4. During the first automatic operation performed by one rotation of the shaft 27, a pin 191 on a link 190 rides along the track 193, 194 and is then deflected by the gate into the path 195 and completes its journey by the track 197. On entering the path 195, the pin 191 strikes the tail of the gate 199A and deflects this gate out of the branch 194, so that during the second automatic operation, the pin moves along the whole length of the branch 194 and completes its journey through the path 196. On entering the path 196, the pin 191 strikes the tail of the gate 199A and restores it to its original position. The link 190, which carries the pin 191, is formed at one end with a fork guided over the shaft 27 and is pivoted at the other end to an arm 189 on a sector 185 in mesh with a sector 134 fast with one of the members 132, Fig. 1, within which the housing 135 is rotatable. During the first automatic operation while the pin 191 travels along the branch 194 to the path 195, the housing is turned by the sectors 185, 134 to the intermediate position A, Fig. 3. In that position, a pinion 143 on the housing lies in the path of a sector 212. This sector is fast with a shaft 213 driven through bevel gearing 215, 216, shaft 217, spur gearing 220, 221, and shaft 180, which is geared to shaft 27. The action of the sector 212 on the bevel pinion 143 causes the housing 135 to turn through 180 degrees, so that when the pin 191 returns by the track 197, the housing 135 is turned down again to replace the record on the turntable for its second side to be played. During the second automatic operation, the housing is swung up past the position A and the pinion 143 passes beyond reach of the sector 212, so that no rotation of the housing 135 in its journals 132 takes place. The movements of the grippers are operated and controlled according to the position of the housing 135 by a cam 169, Fig. 2, on the shaft 27 and by the shaft 180 geared to the shaft 27. At the beginning of the first automatic operation, just after the top record is raised above the others, the cam 169 causes a sector 166 to turn against the action of a spring 167. This imparts movement to sector 165, shaft 161, gear wheel 160 in mesh with gear wheel 159, Fig. 5, sector 157 fast with gear 159 and pinion 156, which at this moment is in the path of sector 157. The rotation of pinion 156, which is fast with pinion 155 on same shaft 154, causes the grippers 148, 149 to be swung in and to grip the record. Near the end of the first automatic operation, the housing 135 having been swung do