Patent GB-316418-A (GB)
Title: Improvements in talking machines
IPC: G11B3/60
Filed: 1928-07-12
Abstract: 316,418. Gramophone Co., Ltd., Knight, E., and Thompsett, H. A. July 12, 1928. Suction-devices for lifting and holding records; magazine gramophones.-A record is maintained in a desired position on a gramophone by a device whereby suction is applied to the record through a hollow body adapted to cover an area of the record surface concentric with the record but outside its centre. The invention is shown applied to a magazine gramophone, in which records are transferred from a pile 6 to the turntable 4 by a swinging conveyer arm 10. The arm is carried by a tubular pillar 9, which is capable of being raised, lowered, and rotated in a bearing sleeve 8. The tube 9 is plugged at each end, and one end communicates by a flexible pipe 20 with an air exhauster 21. The other end of the tube 9 is connected to a pipe 19, which leads to an axial passage 17 in a downwardly extending pin 11 mounted on the free end of the arm 10. The pin 11 carries a member 12 having a flat lower surface to which is secured a circular member 13 of channel section, the part 13, or the side walls thereof, being made of resilient material. The interior of the member 13 communicates through a passage 15 in the part 12 with the passage 17. When the arm 10 is lowered over the pile of records, centred on a. support 5 by a slidable pin 7, the pin 11 depresses the pin 7 and engages in the central hole in the top record, the member 13 resting with its edges in contact with the record surface. A cock 22 on the air pump 21 is then opened either by hand or automatically, for example by a motor-driven cam, and suction is thus applied to the record through the member 13, against which it is held. The arm 10 then transfers the record to the turntable 4 and the cock 22 is opened to release the record before the arm 10 again rises and swnigs back over the magazine. Instead of a single annular member 13, a number of suction-cups, all communicating with the exhaust conduit in the pin 11, may be arranged symmetrically around the pin. As a further alternative, the suction effect may be obtained by causing the hollow bodies to be compressed while in contact with the record surface, the elasticity of the walls causing the hollow bodies afterwards to resume their normal shape, thereby producing a partial vacuum. Turntables.-Light or flexible records may be held against the turntable by suction. As shown in Fig. 5, in the central area of the turntable 4 are perforations 28, below which is fixed a hollow member 26 surrounding a boss 27 on the turntable spindle 3. A pipe 36 leads from the exhausting device to a cup 30, which is an extension of the bearing for the spindle 3, the cup providing an air passage to the interior of the member 26. Glands and packing-rings are provided where necessary to prevent air leakage. A thin rubber pad or the like may be placed on the turntable. With this arrangement, suction is applied to the record when the cock 22 is operated to open the pipe 36 to the pump 21. In the construction shown, the cock is a two-way device, which puts the pump in communication with the member 26 when the suction has been cut off from the conveyer arm 10.