Patent GB-309873-A (GB)
Title: Improvements in and relating to talking machines
IPC: G11B17/16
Filed: 1929-04-16
Abstract: 309,873. Columbia Graphophone Co., Ltd., (Assignees of Erbe, R. R.). April 16, 1928, [Convention date]. Magazine gramophones. - In a magazine gramophone the records are stored in a substantially horizontal position in a stack which is tilted almost to a vertical position for changing a record, the played record being returned to the top of the stack by a rocking carrier and a fresh record released from the bottom of the tilted stack to pass on to the turntable. The machine operates automatically to play through the stack, and as the records are returned to the stack in inverted position both sides are played by playing through the stack twice. Record changing is initiated from the record which acts to close a circuit at the reproducer head and thereby effect lifting and return of the tone-arm, changing of the record and repositioning the tone-arm into playing engagement with the new record. Provision is made for repeating any record, and for arresting the machine after playing any desired number of records, and the mechanism provides for adjustment of the stack and correlated parts when a different diameter of record is employed. The stack of records is supported on a front plate 17, Fig. 5, and a rear bar 14a of a frame 14 pivoted on standards 13 and normally retained in the position shown by an arm 20 resting on an arm 21 fixed to a shaft 22 connected by a belt 29 with a shaft 26. The shaft 26 is rocked by a crank 30 and rod 31 from a cam 33, Fig. 11, on a shaft 34 which can be driven through a clutch 37, normally disengaged, from a shaft 34<a> constantly geared with the turntable spindle 3 driven by the electric motor 4 from mains 9, 10 when the switch 12 is closed. The pick-up or sound-box 8 carrier by the tone-arm 5 carries a pair of contacts 70, 72 one of which, 72, is flexible and fitted with a brush following the stylus 7 whereby when the stylus reaches the continuous groove at the end of a record the brush continues to be advanced by the record grooves and completes a circuit through the contacts 70, 72 to a solenoid 67. When this occurs, the core 66 is drawn in and rocks a pivoted lever 62 to engage the clutch 37 against the separating action of the spring 39, and the shaft 34 is now driven from the shaft 34a and cams thereon effect lifting of the tone-arm and its return clear of the record, the cam 33 rocking the shafts 26, 22 as described above so that the lever 21 allows the stack to rock to a position substantially vertical. In this movement the record carrier 40, Fig. 5, mounted on the shaft 22 and normally surrounding the turntable 2, is rocked into a vertical position to deliver the played record to the top of the stack which is now substantially vertical, and a lever 90 pivoted on the stacksupporting plate 17 and engaging the edge of the bottom record is now rocked by the movement of a lever 93 actuated from the lever 21 to disengage this record from the plate 17 so that it rests on a cushion block 93 and against inclined guides 99. On the return movement of the lever 21 to return the stack and carrier to the position shown an arm 105 fixed to the carrier assists the released record to slide down the guides 99 into position on the turntable, whereupon the tonearm is lowered and moved into playing position on the record and a lug 47<a>, Fig. 11, on the cam 47 acts through a pin 47<b> to press back the pivoted lever 62 so that the clutch 37 no longer drives the cam shaft 34. Means for stopping the machine after playing a predetermined number of records comprises a setting knob and pointer moving over a dial mounted on the base board on a spindle 121 carrying a wheel with radiating pins 125 in the path of an arm 126 on the shaft 26. At each change of a record the arm 126 engages, a pin to turn the wheel until one extended pin 125a is moved against a switch arm 79 in, and opens, the motor circuit. By omitting a pin in the wheel the lever 126 will fail to drive it when the space is brought opposite thereto and the machine will run continuously. Repetition of a record can be effected by withdrawing, by means of a pull knob 133 and Bowden wire 132, a driving pin connecting the belt pulley 28 and shaft 26 so that the record changing mechanism is not operated. To enable the machine to play with records of a different size the stack supports 13 may be carried on slides, and the means for setting the tone-arm in correct starting position may be adjustable simultaneously therewith. Sound reproducer, raising, positioning and lowering. When the contacts 70, 72 on the reproducer head 8 are closed, by the action of the record on the brush 72 at the finish of playing, a circuit is completed through the solenoid 67 to pull on a lever 62 and close a clutch 37 whereby a cam shaft 34 is driven. A cam 47 on this shaft supporting the foot of the tone-arm 5 now lifts the tone-arm in its bearing 6 and another cam 50 on the shaft 34 acts on an arm 51 carried by the tone-arm foot to swing the tone-arm so that the head 8 is carried clear of the record against a resilient stop 53 which reacts to bring the tone-arm against a stop 60 with the head in correct starting position on the fresh record supplied to the turntable. The stop 60 is adjustable, if desired simultaneously with the record stack, according to the size of the record.