Patent GB-772899-A (GB)
Title: Machine for applying protective coatings to the marginal portions of gramophone record discs
IPC: G11B3/70
Filed: 1955-03-03
Abstract: <PICT:0772899/III/1> A machine for treating gramophone record discs comprises a rotatable support with means for securing the disc to the support concentrically with the axes thereof and means for applying a coating to the marginal and edge surfaces of the disc which means comprises a rotatable dispenser roller, with its axis parallel to that of the disc and displaceable radially of the disc and means for temporarily pressing the roller into engagement with the marginal portions of the disc, the roller comprising a hollow body for the coating liquid, a permeable flexible screen surrounding a perforated envelope surface.  The gramophone disc 33 is mounted on a support 29 rotatable on a shaft 9 slidably supported in bearings 10, 11 on a base 12.  A sleeve 13 loosely mounted on the shaft between fixed bearings 14, 15 has a projection 21 through which a wire 22 is passed.  The wire passes over pulleys 23, 24 to spring-urged treadles 26, 27, whereby depressing a pedal causes the shaft 9 to move longitudinally either to cause the disc to come into engagement with a driven member 7 on a concentric shaft 1 or to cause a driven wheel 32 to contact a ridge on the support 29 to reduce its speed.  The disc is secured on the support 29 by a spring 34 which has prongs engaging opposite flat faces of a screw head mounted in the support 29 and passing through the disc.  The coating roller 59 is mounted in a bracket 54 slidably on a base 53 and urged by a wire wound on a spring roller 67 out of contact with the disc.  A stripper roller 65 is rotatably mounted adjacent the coating roller over a tray 66.  The roller 59 is urged to the disc edge by manually operating a rod 69 secured to the bracket 54.  The roller 59 has a hollow cavity for the coating liquid, the surface is perforated and is covered by a permeable pad which is surrounded by an annular permeable and flexible screen.  In operation the disc having been placed on the support 29 the pad 26 is depressed to move the disc into driving engagement with the member 7 having a hollow 8 for the spring 34. The disc is then ground by a manually operated grinding tool pressed against the periphery of the disc.  When grinding is finished the pedal 26 is released and the pedal 27 depressed to bring the roller 32 into engagement with the support to cause it to rotate more slowly for coating.  The coating wheel is then brought into engagement with the disc by operating the rod 69.  In an alternative form of mounting for the disc a spring-urged knob is used instead of the spring 34, pressing the knob projects an end piece and depresses two detents retaining the disc on the support 1 the end piece passes into an aperture in the support 29 and the detents are then released to retain the disc on the support 29.  An alternative form of coating roller mounted on a pivoted arm is used.  The roller is in two parts, one part being an end cap adjustably screwed on to a hub to vary the size of a central groove used for coating the disc, the other part has a series of perforations.  The outer surface is covered by an annular pad of thick nylon web or tricot.