Yarn bobbin - is of a cast aluminium alloy blank turned to the accurate dimensions and age hardened or covered with a hard surface coating

摘要

To produce a light metal yarn bobbin with a hollow shaft and projecting side flanges, the bobbin blank is cast from a high quality aluminium alloy with a strength of 100-140 F, and the blank is turned to give the accurate dimensions. The bobbin is age hardened to increase the surface hardness. The bobbin blank is produced by centrifugal casting, and is tempered by the application of a hard coating, by electro-plating to give a chrome coating. Alternatively, chemically reactive material can be applied to the aluminium alloy surface for conversion of the surface into a hard layer. The aluminium surface can be covered by diffusion coating, or by immersion in a molten bath. The aluminium alloy surface can also be coated with a hard compound material as a metal or alloy, or it can be covered by an enamel coating. The bobbin is, additionally, thermally age hardened. USE/ADVANTAGE - The bobbin is for yarn winding, in a textile machine, which can be rotated at high speeds. The bobbin prodn. is within acceptable mfg. costs, with the required strength performance, and accurate dimensions to give true running at high rotary speeds.