(19)

(11)

EP 1 631 768 A1

(12)

(43) Date of publication: 08.03.2006 Bulletin 2006/10 (21) Application number: 04736320.5 (22) Date of filing: 08.06.2004

(51) International Patent Classification (IPC):  F17C 3/00(1968.09) F17C 13/12(1968.09) F17C 5/00(1968.09) (86) International application number: PCT/GB2004/002424 (87) International publication number: WO 2004/111525 (23.12.2004 Gazette 2004/52)

(84) Designated Contracting States: AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IT LI LU MC NL PL PT RO SE SI SK TR (30) Priority: 11.06.2003 GB 0313483 (71) Applicant: The BOC Group plc Windlesham Surrey GU20 6HJ (GB)	(72) Inventor: ROACH, John Rotherham, South Yorkshire S60 5NT (GB) (74) Representative: Wickham, Michael  C/o Patent and Trademark Department The BOC Group plc Chertsey Road Windlesham Surrey GU20 6HJ Surrey GU20 6HJ (GB)