(19)

(11)

EP 0 020 369 A1

(12)

(43) Date of publication: 07.01.1981 Bulletin 1981/01 (21) Application number: 79900968.0 (22) Date of filing: 24.11.1978

(51) International Patent Classification (IPC):  F28D 1/ 04( . ) F28F 1/ 32( . ) F28D 1/ 053( . ) (86) International application number: PCT/US1978/000175 (87) International publication number: WO 1980/001105 (29.05.1980 Gazette 1980/12)

(84) Designated Contracting States: CH DE FR GB SE (71) Applicant: CATERPILLAR TRACTOR CO. Peoria, Illinois 61629 (US)	(72) Inventors: BENTZ, Erwin J. Washington, IL 61571 (US) STRATTON, Raymond D. Sparland, IL 61565 (US) (74) Representative: Jackson, Peter Arthur, et al  GILL JENNINGS & EVERY Broadgate House 7 Eldon Street London EC2M 7LH London EC2M 7LH (GB)