(19)
(11) EP 0 294 106 A3

(12) EUROPEAN PATENT APPLICATION

(88) Date of publication A3:
25.10.1989 Bulletin 1989/43

(43) Date of publication A2:
07.12.1988 Bulletin 1988/49

(21) Application number: 88304789.6

(22) Date of filing: 26.05.1988
(51) International Patent Classification (IPC)4: B28B 3/20, B28B 3/26
(84) Designated Contracting States:
BE CH DE GB LI SE

(30) Priority: 30.05.1987 JP 136603/87

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

(72) Inventors:
  • Kato, Kiminari 1-302 Town Denjiyama
    Nagoya City Aichi Pref. (JP)
  • Watanabe, Keiichiro 4E Cooperative
    Naka-ku Nagoya City Aichi Pref. (JP)
  • Ishiguro, Tatsuya
    Tajimi City Gifu Pref. (JP)

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


(56) References cited: : 
   
       


    (54) Extruding dies and method of extruding ceramic honeycomb structural bodies by using such extruding dies


    (57) A die for extruding ceramic honeycomb structural bodies, which each contains at least two through holes with partition walls having a plurality of different thicknesses, comprises shaping channels corresponding to a sectional configuration of the ceramic honeycomb structural bodies, and ceramic body feed holes (3), communicating with the shaping channels (2) at inter­secting portions or annular shaping channels portions. The hydraulic diameter of the ceramic body feed holes (3b,3c,3d) communicating with the shaping channels (2b, 2c,2d) producing the thinner partition walls is greater than that of the ceramic body feed holes (3a,3e) communicating with the shaping channels (2a,2c) producing the thicker partition walls. Communicating paths of the ceramic body feed holes (3a,3e) which communicate with the shaping channels (2a,2e) producing the thicker partition walls are bent. This improves the adhesion within the ceramic body.







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