(19)

(11)

EP 0 105 920 A1

(12)

(43) Date of publication: 25.04.1984 Bulletin 1984/17 (21) Application number: 83901752.0 (22) Date of filing: 08.04.1983

(51) International Patent Classification (IPC):  A01C 7/ 04( . ) (86) International application number: PCT/US1983/000501 (87) International publication number: WO 1983/003518 (27.10.1983 Gazette 1983/25)

(84) Designated Contracting States: BE DE FR GB LU SE (30) Priority: 13.04.1982 NL 19820001538 (71) Applicants: VAN WINGERDEN, Aart Fletcher, North Carolina 28732 (US) VISSER, Ton NL-'s-Gravendeel (NL)	(72) Inventors: VAN WINGERDEN, Aart Fletcher, North Carolina 28732 (US) VISSER, Ton NL-'s-Gravendeel (NL) (74) Representative: Mackie, Alexander Walter  Cabinet Simonnot 49, rue de Provence F-75442 Paris Cédex 09 F-75442 Paris Cédex 09 (FR)