GB1325217A - Machine for winding bushings - Google Patents

Abstract

1325217 Capacitors MICAFIL Ltd 6 Sept 1971 [7 Sept 1970] 41455/71 Heading H1M Apparatus for producing a capacitor bushing comprises a self-clamping arbor (Fig. 5, not shown) internally engaging conductive tube 5 supported between rollers 1, 2, 3 and rotating the tube to wind on strip insulating material to form roll 6, and rollers 18 and cutting blade 20 intermittently supplying lengths of metal strip to be wound in with the insulating material to produce coaxial conductive layers in the bushing. Roller 1 is on a fixed support, the support for roller 2 is movable laterally as the roll increases in diameter and roller 3 is weighted and on a pivoted support. The insulating material, e.g. paper, is drawn from roller 9 over a heated roller 10 which is moreover resiliently biased for tensioning the strip. The heating means may be circulating oil which also heats rollers 1 and 2. A cutting means 21 comprising a pair of circular knives cuts the edges of the insulating strip so that the end faces of the finished roll have a desired shape, e.g. conical (Figs. 3, 7, not shown). Rollers 18 may supply a plurality of partially overlapping lengths of metal, e.g. aluminium, strip (Fig. 2, not shown), a pneumatically controlled rope smoothing the strips against guide-plate 24, the strips being simultaneously cut after one revolution. According to the desired shape of the bushing the outer rollers 18 are adjusted or removed as winding proceeds. A measuring means (29) (Fig. 9, not shown) measures the length of insulating material supplied during each revolution of the conductive tube 5, which length is converted to the rod diameter for determining when to introduce the metal strip material.