(19)

(11)

EP 3 938 579 A1

(12)

(43) Date of publication: 19.01.2022 Bulletin 2022/03 (21) Application number: 20712706.9 (22) Date of filing: 11.03.2020

(51) International Patent Classification (IPC):  E01C 1/00(2006.01) E01F 15/04(2006.01) E21F 1/00(2006.01) (52) Cooperative Patent Classification (CPC): E01F 15/04; E21B 1/00; E01C 1/005; E21F 1/003 (86) International application number: PCT/NL2020/050157 (87) International publication number: WO 2020/185078 (17.09.2020 Gazette 2020/38)

(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: 11.03.2019 NL 2022717 (71) Applicant: Cirade 4532 JS Terneuzen (NL)	(72) Inventor: DE GRAAF, Silvester 4532 JS Terneuzen (NL) (74) Representative: V.O.  P.O. Box 87930 2508 DH Den Haag 2508 DH Den Haag (NL)