(19)

(11)

EP 3 924 604 A1

(12)

(43) Date of publication: 22.12.2021 Bulletin 2021/51 (21) Application number: 20707777.7 (22) Date of filing: 13.02.2020

(51) International Patent Classification (IPC):  F01C 1/22(2006.01) F04D 17/18(2006.01) F04C 18/22(2006.01) (52) Cooperative Patent Classification (CPC): F04C 5/00; F04C 18/22; F04C 18/30; F04C 2240/603; F04D 17/18 (86) International application number: PCT/GB2020/050338 (87) International publication number: WO 2020/165592 (20.08.2020 Gazette 2020/34)

(84) Designated Contracting States: AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR Designated Extension States: BA ME Designated Validation States: KH MA MD TN (30) Priority: 15.02.2019 GB 201902106 (71) Applicant: Edwards Limited Burgess Hill, Sussex RH15 9TW (GB)	(72) Inventor: STONES, Ian David Burgess Hill Sussex RH15 9TW (GB) (74) Representative: Totman, Clare Elizabeth  Edwards Limited Innovation Drive Burgess Hill, West Sussex RH15 9TW Burgess Hill, West Sussex RH15 9TW (GB)