Patent GB-503197-A (GB)
Title: Improvements relating to magazine gramophones
IPC: G11B17/02
Filed: 1937-09-29
Abstract: 503,197. Magazine gramophones. MANN, G. S. Sept. 29, 1937, No. 26383. [Class 40 (ii)] The invention relates to magazine gramophones of the kind such as described in Specifications 402,779 and 472,135, in which records stored in a pile are adapted to be transferred to a turntable by means of one or more electromagnets carried by a swing- ing transfer device, and consists in the provision of improved means, comprising specially arranged lever mechanism, whereby a swing- ing movement of the pick-up arm at the end of the playing of a record serves to bring into operation a mechanical coupling between a driving motor and the transfer device and also to operate a switch for energizing the record-lifting magnet or magnets. In the construction shown, the shaft 12 of the driving - motor carries a friction - wheel 13 adapted to be coupled, by a displaceable intermediate wheel 14, to a friction wheel 15 on a shaft 16. The latter carries a worm 17 meshing with a wheel 18 by which, when the gear-train 13, 14, 15 is completed, a crank disc 9 is rotated ; this disc is connected by a telescopic spring- loaded rod 8 to an arm 7 which carries a recordtransferring arm. A spring 20, acting on the spindle 19 of the wheel 14, tends to hold the wheel in engagement with the wheels 13, 15, but 14 is normally held clear of 13, 15 by means of a spring-actuated bell-crank lever, Fig. 3, the long arm of which 22 is engaged by the forked arm 37 of a second bell-crank lever 32. This lever is pivoted on a plate lever 27, itself pivoted at 28, and on the same pivot as that of the lever 32 is an arm 26 having a forked end 261, a friction disc being interposed between the members 26, 32. The longer arm of the lever 32 carries a cam block 33, adapted to engage a gap 34 between the ends of a ring 35 fixed on the motor shaft 12, one end of the ring projecting outwardly at 36. An arm 5 moving with the pick-up arm (not shown) has a pin 25 located between the branches of the fork 26<1>. During the travel of the pick-up arm across the record, the arm 5 moves in the direction of the arrow 5<1>, and when it engages the outer branch of the fork 26<1> the arm 26 is rotated, and with it, through the friction coupling, the lever 32. The cam 33 is, however, repeatedly moved back by the projection 36, and cannot fully engage in the gap 34 until the pick-up enters the run-off groove in the record and causes a sudden movement of the members 26, 32. When this occurs, the part 36 applies an end thrust to the longer arm of the lever 32 and thus causes the plate lever 27 to swing oh its pivot 28. Thereby a switch arm 29 is moved to close at contacts 30, 31 the circuit of magnets for lifting a record and also, preferably, for lifting the pick-up arm by means described in Specification 503,195. At the same time, the fork 37 turns the arm 22, allowing the spring 20 to bring the wheel 14 into engagement with the wheels 13, 15, and the arm 22 is latched by a hooked member 38 in the position to which it has been thus moved. The crank disc 9 is thereupon driven by the motor, swinging the record-transfer arm, and after the disc has made half a revolution a cam 40 on the disc engages a projection 41 on the plate lever 27, returning the parts 27, 32 to their initial position. In this movement, the contacts 30, 31 are opened, and the associated magnets de-energized, so that the transferred record is dropped on the turntable and the pick-up is lowered. The drive from the motor to the crank disc 9 is maintained (to allow the recordtransfer arm to return to its original position), until the cam 40 trips the catch 38 and the arm 22 is then allowed to lift the wheel 14 out of driving engagement. Means may be provided for disconnecting the switch mechanism from the main power supply circuit when the magazine platform or the like has reached a predetermined height. Specification 403,786 also is referred to.