(19)

(11)

EP 0 633 995 A1

(12)

(43) Date of publication: 18.01.1995 Bulletin 1995/03 (21) Application number: 93908040.0 (22) Date of filing: 13.04.1993

(51) International Patent Classification (IPC):  F24D 17/ 00( . ) F24H 1/ 20( . ) (86) International application number: PCT/GB1993/000773 (87) International publication number: WO 1993/021482 (28.10.1993 Gazette 1993/26)

(84) Designated Contracting States: AT BE CH DE DK ES FR GB GR IE IT LI LU MC NL PT SE (30) Priority: 11.04.1992 GB 19920008184 (71) Applicant: THE VICTORIA UNIVERSITY OF MANCHESTER Manchester M13 9PL (GB)	(72) Inventor: AXCELL, Brian P. Appleton, Warrington WA4 5AF (GB) (74) Representative: Ajello, Michael John  207 Moss Lane Bramhall Stockport Cheshire SK7 1BA Bramhall Stockport Cheshire SK7 1BA (GB)