(12) INTERNATIONAL APPLICATION PUBLISHED UNDER THE PATENT COOPERATION TREATY (PCT) (19) World Intellectual Property Organization 111111111DI111ii11011111l11IIIDIID111111111111111 International Bureau (10) International Publication Number (43) International Publication Date W O 2020/236212 A1 26 November 2020 (26.11.2020) W IP0 PCT (51) International Patent Classification: TEHYORCO.,LTD.; I &36,Lane338, SidongRd., San E06B 9/322 (2006.0 1) sia Dist., New Taipei City, 23743 (TW). (21) International Application Number: (72) Inventor; and PCT/US2019/061296 (71) Applicant (forAO, B, BJ, B W, C, CG, C1, CM, DJ, DZ, EG, GA, GH, GAMGN, GQ, GE kE, KA, LR, LS L, AlA, (22)InternationalFilingDate3 November 2019 (13.11.2019) AG, ML, MR MW AZ, NA, NE, NG, R, SC, SD, SL, SN, ST SZ, TD, TG, 2N, TZ, UG, ZA ZW only): HUANG, (25) Filing Language: English Chien-Fong [US/US]; 770 S. Epperson Drive, City of In (26) Publication Language: English dustry, CA 91748 (US). (72) Inventor: HUANG, Chin-Tien; 1 & 36, Lane 338, Sidong (30)PriorityData: 23 May 2019 (23.05.2019) US Rd., Sansia Dist., New Taipei City, 23743 (TW). A, (74) Agent: CHEN, Ying; Chen Yoshimura LLP, 750 W Hamil (71) Applicant (for all designated,'tates exceptA, B, R.B ton Ave. Unit C, San Pedro, CA 90731 (US). CF, CG, CI, C, DJ, DZ, GA, GH, GLGN, GQ, GTE KV, t LR, LS, LY, MA, MGML, AIR,MW MZ, NA, NE, NG, RW, (81) Designated States (unless otherwise indicated, for every SC, SD, SLSN, ST, SZ, TD, TG, TN, TZ, UG ZM, Z): kind of national protection available) AE, AG, AL, AM, AO, AT, AU, AZ, BA, BB, BG, BH, BN, BR, BW, BY, BZ, CA, CH, CL, CN, CO, CR, CU, CZ, DE, DJ, DK, DM, DO, (54) Title: WINDOW SHADE AND SPRING DRIVE SYSTEM THEREOF 1 , 1128 112A;124 )116A 118 106A " -184 1- 150 118A 166106 116B 126-- 193 188 1068 -- 1086 190 -- 114A19 122 11 0 168 162- 13 - ~ ~ 114 195 164 FIG. 1 NA (57) Abstract: A spring drive system for a window shade includes a housing, a first and a second gear engaged with each other and r respectively assembled about a first and a second pivot axis, two springs respectively assembled at two opposite sides of the second gear and respectively connected with two take-up reels provided on the first gear, a first cord drum and a third gear fixedly connected with each other and assembled about a third pivot axis, the first and third gears being respectively located at different levels along the first and third pivot axes and respectively engaged with a first gear train, a second cord drum and a fourth gear fixedly connected with each other and assembled about a fourth pivot axis, the second and fourth gears being respectively located at different levels along the second and fourth pivot axes and respectively engaged with a second gear train. W O 2020/236212 A||||||||||||||||||||||||||||I||||||||||||||||||||||||||||||| DZ, EC, EE, EG, ES, F, GB, GD, GE, GH, GM, GT, HN, HR, HU, ID, [L, IN, IR, IS, JO, JP,R KE, KG, KH, KN, KRP, KR, KW, KZ, LA, LC, LK, LR, LS, LU, LY, MA, MD, ME, MG, MK, MN, MW, MNX, MY, MZ, NA, NG, NI, NO, NZ, OM, PA, PE, PG, PH, PL, PT, QA, RO, RS, RU, RW, SA, SC, SD, SE, SG, SK, SL, SM, ST, SV SY, TH, TJ, TM, TN, TR, TT, TZ, UA, UG, US, UZ, VC, VN, ZA, ZM, ZW. (84) Designated States (unless otherwise indicated, for every kind of regional protection available): ARIPO (BW, Gi, GM, KE, LR, LS, MW, MZ, NA, RW, SD, SL, ST, SZ, TZ, UG, ZM, ZW), Eurasian (AM, AZ, BY, KG, KZ, RU, TJ, TM), European (AL, AT, BE, BG, CH, CY, CZ, DE, DK, EE, ES, FI, FR, GB, GR, HR, HU, IE, IS, IT, LT, LU, LV, MC, MK, MT, NL, NO, PL, PT, RO. RS, SE, SI, SK, SM, TR), OAPI (BF, BJ, CF, CG. CI, CM, GA, GN, GQ, GW, KM, ML, MR, NE, SN, TD, TG). Declarations under Rule 4.17: - ofinventorship (Rule 4.17(iv)) Published: - with international search report (Art. 2](3))