(19)

(11)

EP 0 041 981 A1

(12)

(43) Date of publication: 23.12.1981 Bulletin 1981/51 (21) Application number: 81900049.0 (22) Date of filing: 19.12.1980

(51) International Patent Classification (IPC):  H03D 1/ 18( . ) (86) International application number: PCT/AU1980/000111 (87) International publication number: WO 1981/001921 (09.07.1981 Gazette 1981/16)

(84) Designated Contracting States: AT CH DE FR GB LI NL SE (30) Priority: 21.12.1979 AU 19790001815 (71) Applicant: MARK II ENTERPRISES PTY. LIMITED St. Leonards, N.S.W. 2065 (AU)	(72) Inventors: GREEN, David John Cremorne, N.S.W. 2090 (AU) FREW, Wayne Rex Cremorne, N.S.W. 2090 (AU)