(19)

(11)

EP 0 939 873 A1

(12)

(43) Date of publication: 08.09.1999 Bulletin 1999/36 (21) Application number: 96940544.0 (22) Date of filing: 20.11.1996

(51) International Patent Classification (IPC):  F16L 37/ 12( . ) F16L 37/ 098( . ) (86) International application number: PCT/US1996/018587 (87) International publication number: WO 1998/022743 (28.05.1998 Gazette 1998/21)

(84) Designated Contracting States: DE FR GB IT (71) Applicant: PROPRIETARY TECHNOLOGY, INC. Bloomfield Hills, Michigan 48302-7048 (US)	(72) Inventor: BARTHOLOMEW, Donald, D. Mount Clemens, MI 48045 (US) (74) Representative: Price, Nigel John King  J.A. KEMP & CO. 14 South Square Gray's Inn London WC1R 5LX London WC1R 5LX (GB)