(19)

(11)

EP 3 746 721 A1

(12)

(43) Date of publication: 09.12.2020 Bulletin 2020/50 (21) Application number: 19747424.0 (22) Date of filing: 29.01.2019

(51) International Patent Classification (IPC):  F24F 13/24(2006.01) G10K 11/16(2006.01) F24F 13/06(2006.01) (86) International application number: PCT/SE2019/050069 (87) International publication number: WO 2019/151931 (08.08.2019 Gazette 2019/32)

(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: 01.02.2018 SE 1850117 (71) Applicant: Hiak AB 776 28 Hedemora (SE)	(72) Inventor: HÖRLIN, Nils-Erik 754 18 Uppsala (SE) (74) Representative: Bjerkéns Patentbyrå KB (Gävle)  Box 1274 801 37 Gävle 801 37 Gävle (SE)