Europaisches P a t e n t a m t European Patent Office © Publication number: Office europeen des brevets © EUROPEAN 050 723 A3 PATENT APPLICATION © IntCI.3: H 01 C 7 / 1 2 H 01 T 5 / 0 4 © Application number: 81106859.2 @ Date of filing: 02.09.81 © Priority: 27.10.80 US 200931 ©Applicant: GENERAL ELECTRIC COMPANY 1 River Road Schenectady New York 12305(US) © Date of publication of application: 05.05.82 Bulletin 82/18 © Date of deferred publication of search report: 27.04.83 © Designated Contracting States: CH DE FR LI SE 0 © Inventor: Kresge, James Stanley 87 Mountain Drive Pittsfield Massachusetts 01201 (US) @ Inventor: Sakshaug, Eugene Clemens Grove Avenue Lanesborough Massachusetts 01237(US) © Representative: Voigt, Reinhard, Dipl.-lng. et al, Kaiserstrasse 41 D-6000 Frankfurt (Main) 1(DE) © Grading means for high voltage metal enclosed gas insulated surge arresters. © Capacitance grading is provided within gas insulated lightning arresters (10) containing stacked zinc oxide varistors (14) by means of a grading ring (6) electrically connected to the line terminal or, for arresters of the higher voltage ratings, by means of a plurality of telescoping external electrostatic shields (17-20). The shields (17-20) are arranged /2, /3) between sequential so that the degree of overlap shields decreases from the line end to the ground end of the varistor stacks. The capacitance grading is provided by the degree of overlap (( (2, ( 3) between the sequential shields (17-20) and the ratio of the radii (RB, RA) of the overlapping shields. < « CM IN o LO O h 3 0. HI Croydon Printing Company Ltd 0 0 5 0 7 2 3 J cuiupuan raiem Office ) Application number EUROPEAN SEARCH R E P O R T EP "U1UMUIJ j UUUUMbN I 5 CONSIDERED TO BE RELEVANT wifliiun ui uvwuiiitiiii wun inaicaiion. wnere appropriate, of relevant passages Heievant to claim CK-ft-/ (MITSUBISHI DENKI K.K. ) *Claims 1,2,4,5; 1, l i n e s page 1-13; 7, l i n e 23 - p a g e 8 , page line 15; 10, l i n e s 2 2 - 2 9 ; page l i n e s 5-13; p a g e 11, figures 3,6* 1,2,1 ,12 uc-a-j uu^r 16 1 (HITACHI L T D . ) * C l a i m 1; p a g e 6, p a r a g r a p h s 1,3; 9, 2 - page 1 0 , page paragraph paragraph 1; f i g u r e 1* 1,2, IE ly^t (MITSUBISHI DENKI K.K. ) *Claims 1,2,3,9,10,11; page lines 14-31; figures 3,4* 1,2,16 81 10 6859 CLASSIFICATION OF THE APPLICATION (Int. CI. ») H 01 H 01 C T 7/12 5/04 6/ TECHNICAL FIELDS • SEARCHED (Int. CI. ») H 01 H 01 C T hid pioaciu waiwi ruuuu nas ueen arawn up ior an Claims fHE HAGUE (: f: ^: ): ' : @>oei01 completion 01ine searcn 24-01-1983 i r-uun i ur 01 1CU UUbUMCIM Io particularly relevant if taken alone particularly relevant if combined with another document of the same category technological background non-written disclosure intermediate document r: :: ): .: txaminer DECANNIERE L . J . theory or principle underlying the invention earlier patent document, but published on, or after the filing date document cited in the application document cited for other reasons i . memDer 01 me same patent tamiiy, corresponding document