(19)

(11)

EP 0 039 673 A1

(12)

(43) Date of publication: 18.11.1981 Bulletin 1981/46 (21) Application number: 80900026.0 (22) Date of filing: 09.11.1979

(51) International Patent Classification (IPC):  G01F 1/ 00( . ) G01F 9/ 00( . ) (86) International application number: PCT/US1979/000974 (87) International publication number: WO 1981/001462 (28.05.1981 Gazette 1981/13)

(84) Designated Contracting States: AT CH DE FR GB NL SE (71) Applicant: CATERPILLAR TRACTOR CO. Peoria, Illinois 61629 (US)	(72) Inventors: NEWMAN, Virgil H. Washington, IL 61571 (US) TIDABACK, Frank W. Pekin, IL 61554 (US) JACOBSON, Wayne D. Peoria, IL 61614 (US) HOAGLAND, Donald D. Peoria, IL 61614 (US)