Patent GB-557520-A (GB)
Title: An improved automatic phonograph
IPC: G11B17/16
Filed: 1942-04-13
Abstract: 557,520. Automatic gramophones. OFFEN, F. J. April 13, 1942, No. 4836. Convention date, May 7, 1941. [Class 40 (ii)] The invention comprises a combination of many features in a magazine gramophone in which the record discs are stacked above a turntable, delivered one at a time to a turntable below, reversed for the playing of the second side after the first, and finally dropped into a receptacle at the side of the turntable, means being provided to position the pick-up according to the diameter of the record, and to set the machine for playing one side of the record only and for rejecting a record, as desired. Magazine. This is an improvement in the arrangement described in Specifications 486,999 and 511,840. The record discs are threaded on a vertical central stem 37, Fig. 1, above the turntable 33 and are individually supported at the edge by a set of spaced vanes 36; and the hole stack is moreover held up from underneath by an arm 50. The central stem 37 is fitted with a knob 41 and is detachably mounted in a sleeve 38 on an arm 40 carried by the motor board 32. The vanes 36 are individually rotatable on a column 76, Figs. 6 and 7, and provided with lugs 77 adapted to co-operate with a fixed comb 81 and a rotatable sleeve 74 to control the sequential operations of the vanes. The vanes 36 above the lowest one in operative position are locked against rotation by the lugs 77 lying against the teeth of the comb 81. During the record changing period an elevator 47 is moved up to support the records then the arm 50 is swung out and the sleeve 74 is rotated clockwise so that a shouldered ledge at its upper end engages the lug 77 of the lowest vane in operative position and turns that vane out, thereby dropping the lowest record on to elevators 47, 48 which have meanwhile been raised. The arm 50 is then swung back and the sleeve 74 also rotated back to allow the column 76 to move down to bring the vanes down one step in readiness for the release of the next record at the next operation. The elevators 47, 48, after receiving the record released from the magazine, are depressed to locate the record on the turntable 35 and leave it free to be rotated thereby. When the magazine has been emptied and is to be reloaded, the column 76 is raised by a knob 90 bringing all the lugs 77 opposite the gaps in the comb 81, then the knob is turned counterclockwise to bring all the vanes to operative position. A ratchet device 91, 92 prevents clockwise rotation of the column 76. The sleeve 74 is rotated forward and backward by a rack 84 connected to a lever 85 controlled by a cam 75 and a spring 87. The pillars 47, 48 are operated by levers 100, 106 controlled by cams 105, 112 respectively. The record supporting arm 50 is moved in and out by a rack 257, Fig. 25, connected to a lever 258 controlled by a cam 260. The cams 75, 105, 112 and 260 are all on a hollow shaft 68, Fig. 23, around a shaft 60. Record inversion and discharge. During record changing operation, before the operation of the magazine, the played record is lifted above the turntable by the elevators 47, 48, Fig. 1, then an arm 42 swinging about a pillar 44 is brought between the lifted record and the turntable 33 with the central grippers 46 turned upwards. The elevators 47, 48, lower the record on the grippers and the arm 42 swings back over the receptacle 113. If the reverse side of the record is not to be played, the record is dropped in the receptacle 113. If the reverse side of the record is to be played, the arm 42 is rotated in a sleeve 43 to invert the record and is swung back to replace the inverted record on the turntable. The arm 42 remains over the turntable while the reversed record is played, after which the record is lifted by the elevators 47, 48 and again gripped by the central gripper 46. The arm is then swung out and the record dropped in the receptacle 113. The gripper 46 comprises two jaws 141, 142, Fig. 28, on levers 143, 144 pivoted at 145, 145 and urged towards each other by a spring 146. The jaws are forced apart to grip the record by means of a wedge 147 at the end of a rod 148 terminating in a collar 150, Fig. 26, within the pillar 44. The collar 150 bears against a bell-crank 151 resting on a rod 152 controlled by pins 160 on a cam 161 through linkwork 153 ... 157. The swinging movements of the arm 42 about the axis of the pillar 44 are performed by a rack 132 engaging a pinion 131 on the pillar and operated through springs 138, 140 by a crank 133 on a shaft 134 controlled by the co-operation of another crank 135 with a cam 137. The shaft 134 is slidably set under control of knob 57. In one position, the crank 135 follows one groove of cam 137 to perform the return of the record to the turntable when both sides are to be played. In the other position, the crank 135 follows another track of the cam 137 and the record is not returned to the turntable for the playing of the second side. The turning movements of the arm 42 in the sleeve 43 to invert the records are performed by a rack 116 which engages a pinion 115 on the arm 42 and is carried by a circular rack 118 controlled by a spring 124 and through gearing 121, 125, 126 and a lever 127 by a cam 130. The cams 161, 137 and 130 are all on the sleeve 68. Pick-up arm mechanism. The pick-up arm 30 is carried bv the rotatable vertical sleeve 165, Fig. 20 through which a rod 166 moves for raising and lowering the pick-up arm about a pivot on an arm 165a at the top of the sleeve 165. The rod 166 has a collar 167 co-operating with a fork 170 on a lever 168 for raising and lowering the pick-up. The lever 168 is controlled by a cam 172 on the shaft 66. The rotatable sleeve 165 has an arm 174 provided with pins 178, 180 co-operating with the bent end 177 of a lever 175 for moving the pick-up arm outwards after the playing of a record and returning it inwards over the edge of the fresh record. The lever 175 is controlled by a cam 176, Fig. 23, on the shaft 66. The arm 174 is also provided with a stop 192 adapted to abut a pin 190 or 191 on a lever 188 during the inward return of the pick-up arm according to the diameter of the record on the turntable, and with a spring catch device 194 for giving an additional movement to the pick-up arm after it has been lowered on the edge of the record, thereby to lead the needle into the starting groove. The sleeve 165 is also fitted with an arm 181 engaging a looped lever 183 on a spindle 184 to operate the mechanism which controls the record changing operation at the end of the playing of a record. Control of pick-up arm by diameter of record on turntable. When a record has been placed on the turntable, a cam 186, Figs. 14 and 23, on the shaft 66 allows a feeler arm 51 to be turned inwards by a spring until its end 52 is arrested by the edge of the record. The arm 51 is fast with the lever 188 and the cam follower 187 on a common spindle 185. The position thus given to the lever 188 depends on the diameter of the record; and according to this setting the pick-up arm is positioned over the edge of the record by the abutment of the stop 192 with the pin 190 or 191 according to the diameter of the record as mentioned above. Record changing operation. This is brought about by the usual quick inward movement of the pick-up arm when the playing is completed. During the playing of a record, the movement of the pick-up arm 30 is transmitted by the arm 181, Fig. 20, and looped lever 183 to spindle 184 as mentioned above. The spindle 184 is connected by a crank and a link 215, Fig. 14, to a lever 216 friction coupled to a lever 214 on the same spindle 317. A lever 218 is pivoted at 220 to the end of the lever 214 and is gradually moved towards the turntable spindle 212 by the inward movement of the pick-up arm. When the inner end of the lever 218 reaches the path of a crank 213 on the turntable spindle, the levers 218, 214 are periodically pushed back by the crank 213, until the quick inward movement of the pick-up arm occurs at the end of the playing of the record. Then the crank 213 deflects the lever 218 about its pivot 220 against the action of a spring 221, and the outer end 222 of the lever 218 turns a lever 208 thereby closing a switch 201 serving to start the motor which drives the record changing mechanism. When the record changing operation is completed, .the lever 208 is turned back to open the switch 201 by a pawl 224 on a lever 225 controlled by the co-operation of a lever 228 with a cam on shaft 66. At the end of its stroke, the pawl 224 is deflected by a stop 232 to leave the lever 208 free. Playing one or both sides of records. This is determined by the setting of a knob 57, Figs. 1 and 22, controlling the position of bell-crank 281, link 283, crank 284 and arms 285, 286 and also the position of the shaft 134, Fig. 26, as mentioned above. When this mechanism is set as shown in Fig. 22 for playing one side only of the records, a stop 287 on the arm 285 blocks an arm 288 fast with the arm 225 carrying the pawl 224 ; this pawl cannot therefore operate to trip the lever 208 to open the switch 201 until the complete cycle has been performed. Due to the setting of the shaft 134, the record is not returned as explained above. The pick-up however, is lowered but comes to rest for a short time only on a small button 33a at the side of the turntable, the continued operation of the cam devices, due to the switch 201 remaining closed soon causing the pickup to be lifted and swung out again. Record repeat mechanism. To enable this, the several cams required for the various operations of the machine are divided into two groups 67, 70, Fig. 23. The group 70 used for record changing is carried by a sleeve 68 on the shaft 60 driven by a motor (not shown) which is switched on by the switch 201, Figs. 14 and 22, when an operation is to be performed. Rotation is transmitted from shaft 60 to sleeve 68 through a clutch 265, and from shaft 60 to sh