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(11)

EP 4 337 896 A1

(12)

(43) Date of publication: 20.03.2024 Bulletin 2024/12 (21) Application number: 21742680.8 (22) Date of filing: 22.06.2021

(51) International Patent Classification (IPC):  F24F 13/14(2006.01) F24F 13/22(2006.01) E06B 7/084(2006.01) (52) Cooperative Patent Classification (CPC): F24F 13/22; F24F 13/1413; F24F 13/1426 (86) International application number: PCT/BG2021/050002 (87) International publication number: WO 2022/266727 (29.12.2022 Gazette 2022/52)

(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 (71) Applicants: Antonov, Stefan Pavlov 1000 Sofia (BG) Cankova, Stefana Boykova 9000 Varna (BG) Stefanov, Kalin Raykov 9000 Varna (BG)	(72) Inventors: Antonov, Stefan Pavlov 1000 Sofia (BG) Cankova, Stefana Boykova 9000 Varna (BG) Stefanov, Kalin Raykov 9000 Varna (BG) (74) Representative: Ilieva, Angelina Stanimirova et al 2 Nikolay Haytov Str., ent. G, fl. 5, Apt. 13 1113 Sofia 1113 Sofia (BG)