(19)

(11)

EP 0 513 314 A1

(12)

(43) Date of publication: 19.11.1992 Bulletin 1992/47 (21) Application number: 92901033.0 (22) Date of filing: 09.12.1991

(51) International Patent Classification (IPC):  A01D 31/ 00( . ) A01D 45/ 00( . ) (86) International application number: PCT/NL1991/000256 (87) International publication number: WO 1992/010084 (25.06.1992 Gazette 1992/14)

(84) Designated Contracting States: AT BE CH DE DK ES FR GB GR IT LI NL SE (30) Priority: 07.12.1990 NL 19900002697 (71) Applicant: Zijlstra & Bolhuis B.V. NL-9645 LA Veendam (NL)	(72) Inventors: TIMMERMANS, Hubertus, Renier, Maria NL-9713 AE Groningen (NL) HILVERTS, Jakob NL-9645 AJ Veendam (NL) (74) Representative: Smulders, Theodorus A.H.J., Ir., et al  Vereenigde Octrooibureaux Nieuwe Parklaan 97 NL-2587 BN 's-Gravenhage NL-2587 BN 's-Gravenhage (NL)