(19)
(11) EP 1 276 118 A3

(12) EUROPEAN PATENT APPLICATION

(88) Date of publication A3:
19.11.2003 Bulletin 2003/47

(43) Date of publication A2:
15.01.2003 Bulletin 2003/03

(21) Application number: 02254811.9

(22) Date of filing: 09.07.2002
(51) International Patent Classification (IPC)7: H01B 17/02, H01B 17/08
(84) Designated Contracting States:
AT BE BG CH CY CZ DE DK EE ES FI FR GB GR IE IT LI LU MC NL PT SE SK TR
Designated Extension States:
AL LT LV MK RO SI

(30) Priority: 12.07.2001 JP 2001211944

(71) Applicant: NGK INSULATORS, LTD.
Nagoya City Aichi Pref. (JP)

(72) Inventors:
  • Mitsuharu, Okamoto
    Mizuho-ku Nagoya-shi, Aichi-ken 467-8530 (JP)
  • Ryoichi, Mine
    Mizuho-ku Nagoya-shi, Aichi-ken 467-8530 (JP)
  • Takao, Nakamura
    Mizuho-ku Nagoya-shi, Aichi-ken 467-8530 (JP)

(74) Representative: Paget, Hugh Charles Edward et al
MEWBURN ELLIS York House 23 Kingsway
London WC2B 6HP
London WC2B 6HP (GB)

   


(54) Insulator and insulator apparatus


(57) An insulator includes a disklike shed portion (21) and a plurality of annular rib portions (23a to 23e) formed concentrically on the underside of the shed portion (21) and projecting downward along respectively predetermined lengths. Among the rib portions (23a to 23e), a first rib portion (23a) located outermost is the longest; a second rib portion (23b) is shorter than the first rib portion (23a); a third rib portion (23c) assumes a length such that the third rib portion (23c) intersects a straight line L1 tangent to the end of the first rib portion (23a) and to that of the second rib portion (23b); and a fourth rib portion (23d) assumes a length such that the fourth rib portion (23d) intersects a straight line L2 tangent to the end of the first rib portion (23a) and to that of the third rib portion (23c).






Search report