SEALED BUSHING Russian patent published in 2005 - IPC

FIELD: power engineering; switchgear of electrical power installations, primarily high-voltage ones.

SUBSTANCE: proposed sealed bushing has bushing insulator with central bore whose external butt-end surface is inwardly tilted; current system incorporating series-connected external contact lead 7 with annular surface-mounting surface at the same time closing insulator central bore; tubular thin-wall central contact member 4 with outward flanging 5 at same angle as insulator butt-end surface to form circular supporting surface that functions on other end as internal contact lead 17 of bushing; external contact lead 7 and thin-wall tubular central contact member 4 are tightly pressed together and to external butt-end surface of insulator through their annular supporting surfaces with aid of spring-loaded central rod 11 provided with articulated joint 12 that rests on internal butt-end of insulator through brackets of bushing internal support 13; there is circularly enclosed wave-like bulge 6 in central region of annular contacting surface of thin-wall central contact member 4 flanged at certain angle, circle height being equal over perimeter; its surface shape in any radial section gradually changes at points of its turning from flat surface to bulge at minimal possible radius concerning manufacturability and maximal physically possible radius at wave-like bulge top with physically possible greater width of bulge part having this maximal radius within adopted width of flanging. In addition, one or more parallel-operating thin-wall current-carrying parts may be introduced in current-carrying system of bushing where they are to be disposed inside tubular central contact member and provided with respective surfaces contacting external and internal contact leads. External contact lead of bushing may be provided with protective cylinder rigidly fixed thereto over external diameter, enclosed on external butt-end, and disposed so that clearance is formed relative to diameter of contact lead and to equal diameter of insulator, flexible gasket additionally sealing top part of bushing being placed in this clearance. Contact leads may be additionally provided with through strips having copper middle part and aluminum parts functioning as bushing leads.

EFFECT: enhanced reliability of sealing, reduced input of magnet wire and auxiliary materials, reduced size of bushing.

4 cl, 2 dwg