{"id":1787,"date":"2026-01-09T05:16:11","date_gmt":"2026-01-09T05:16:11","guid":{"rendered":"https:\/\/tractorptoshaft.net\/?p=1787"},"modified":"2026-01-09T05:16:11","modified_gmt":"2026-01-09T05:16:11","slug":"high-speed-drive-shafts-for-automated-cartoners-fillers","status":"publish","type":"post","link":"https:\/\/tractorptoshaft.net\/vi\/application\/truc-truyen-dong-toc-do-cao-cho-may-dong-goi-va-chiet-rot-tu-dong\/","title":{"rendered":"Tr\u1ee5c truy\u1ec1n \u0111\u1ed9ng t\u1ed1c \u0111\u1ed9 cao cho m\u00e1y \u0111\u00f3ng th\u00f9ng v\u00e0 chi\u1ebft r\u00f3t t\u1ef1 \u0111\u1ed9ng"},"content":{"rendered":"
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Tr\u1ee5c truy\u1ec1n \u0111\u1ed9ng t\u1ed1c \u0111\u1ed9 cao cho m\u00e1y \u0111\u00f3ng g\u00f3i v\u00e0 chi\u1ebft r\u00f3t t\u1ef1 \u0111\u1ed9ng t\u1ea1i c\u00e1c trung t\u00e2m logistics c\u1ee7a H\u00e0 Lan.<\/h1>\n

T\u1ed1i \u01b0u h\u00f3a m\u1eadt \u0111\u1ed9 m\u00f4-men xo\u1eafn v\u00e0 \u0111\u1ed9 ch\u00ednh x\u00e1c v\u1ecb tr\u00ed cho th\u1ebf h\u1ec7 m\u00e1y \u0111\u00f3ng g\u00f3i c\u00f4ng nghi\u1ec7p ti\u1ebfp theo t\u1ea1i H\u00e0 Lan.<\/p>\n

Y\u00caU C\u1ea6U B\u00c1O GI\u00c1 S\u1ed0 L\u01af\u1ee2NG L\u1edaN NGAY B\u00c2Y GI\u1edc<\/a><\/div>\n<\/div>\n
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\u201cTrong 18 n\u0103m ch\u1ea9n \u0111o\u00e1n c\u00e1c s\u1ef1 c\u1ed1 truy\u1ec1n \u0111\u1ed9ng \u0111i\u1ec7n t\u1ea1i c\u00e1c nh\u00e0 m\u00e1y \u0111\u00f3ng g\u00f3i th\u1ef1c ph\u1ea9m \u1edf B\u1eafc Brabant v\u00e0 c\u00e1c ph\u00f2ng th\u00ed nghi\u1ec7m v\u00f4 tr\u00f9ng g\u1ea7n s\u00e2n bay Schiphol, t\u00f4i \u0111\u00e3 ch\u1ee9ng ki\u1ebfn \u200b\u200b\u0111\u1ee7 m\u1ecdi chuy\u1ec7n. H\u1ea7u h\u1ebft c\u00e1c qu\u1ea3n l\u00fd nh\u00e0 m\u00e1y \u0111\u1ec1u ngh\u0129 r\u1eb1ng tr\u1ee5c truy\u1ec1n \u0111\u1ed9ng ch\u1ec9 l\u00e0 m\u1ed9t m\u1ea3nh kim lo\u1ea1i quay \u2013 cho \u0111\u1ebfn khi m\u00e1y \u0111\u00f3ng h\u1ed9p t\u1ed1c \u0111\u1ed9 cao c\u1ee7a h\u1ecd b\u1eaft \u0111\u1ea7u l\u1ec7ch kh\u1ecfi v\u1ecb tr\u00ed \u0111\u1ecbnh v\u1ecb do hi\u1ec7n t\u01b0\u1ee3ng xo\u1eafn v\u1eb7n. T\u00f4i nh\u1edb m\u1ed9t d\u1ef1 \u00e1n \u1edf Rotterdam, n\u01a1i tr\u1ee5c ban \u0111\u1ea7u c\u1ee7a m\u00e1y chi\u1ebft r\u00f3t rung l\u1eafc m\u1ea1nh \u0111\u1ebfn m\u1ee9c l\u00e0m v\u1ee1 c\u00e1c l\u1ecd th\u00e0nh m\u1ecfng v\u1edbi t\u1ed1c \u0111\u1ed9 400 l\u1ecd m\u1ed7i ph\u00fat. B\u00ed quy\u1ebft m\u00e0 ch\u00fang t\u00f4i \u0111\u00e3 ho\u00e0n thi\u1ec7n t\u1ea1i EVER-POWER kh\u00f4ng ch\u1ec9 n\u1eb1m \u1edf s\u1ee9c m\u1ea1nh th\u00f4; m\u00e0 c\u00f2n \u1edf vi\u1ec7c ki\u1ec3m so\u00e1t c\u1ed9ng h\u01b0\u1edfng h\u00e0i h\u00f2a v\u00e0 \u0111\u1ed9 ch\u00ednh x\u00e1c kh\u00f4ng c\u00f3 \u0111\u1ed9 r\u01a1. Ch\u00fang t\u00f4i kh\u00f4ng ch\u1ec9 b\u00e1n linh ki\u1ec7n; ch\u00fang t\u00f4i gi\u1ea3i quy\u1ebft nh\u1eefng v\u1ea5n \u0111\u1ec1 c\u01a1 kh\u00ed 'v\u00f4 h\u00ecnh' khi\u1ebfn c\u00e1c \u0111\u1ed9i b\u1ea3o tr\u00ec ph\u1ea3i th\u1ee9c \u0111\u1ebfn 3 gi\u1edd s\u00e1ng.\u201d<\/p>\n<\/div>\n

H\u00e0 Lan l\u00e0 tr\u00e1i tim kh\u00f4ng th\u1ec3 tranh c\u00e3i c\u1ee7a ng\u00e0nh c\u00f4ng nghi\u1ec7p \u0111\u00f3ng g\u00f3i t\u1ef1 \u0111\u1ed9ng ch\u00e2u \u00c2u. T\u1eeb c\u00e1c trung t\u00e2m ch\u1ebf bi\u1ebfn s\u1eefa kh\u1ed5ng l\u1ed3 \u1edf Friesland \u0111\u1ebfn khu v\u1ef1c Brainport Eindhoven c\u00f4ng ngh\u1ec7 cao, nhu c\u1ea7u v\u1ec1 \u0111\u1ed9 tin c\u1eady 24\/7 l\u00e0 kh\u00f4ng th\u1ec3 thi\u1ebfu. Khi b\u1ea1n nh\u00ecn v\u00e0o m\u1ed9t m\u00e1y \u0111\u00f3ng h\u1ed9p ki\u1ec3u tr\u01b0\u1ee3t hi\u1ec7n \u0111\u1ea1i ho\u1eb7c m\u1ed9t m\u00e1y chi\u1ebft r\u00f3t quay, tr\u1ee5c truy\u1ec1n \u0111\u1ed9ng ch\u00ednh l\u00e0 xung l\u1ef1c quan tr\u1ecdng. N\u00f3 ph\u1ea3i k\u1ebft n\u1ed1i kho\u1ea3ng c\u00e1ch gi\u1eefa c\u00e1c \u0111\u1ed9ng c\u01a1 servo m\u00f4-men xo\u1eafn cao v\u00e0 c\u00e1c h\u1ed9p s\u1ed1 \u0111\u1ecbnh v\u1ecb ph\u1ee9c t\u1ea1p v\u1edbi \u0111\u1ed9 ch\u00ednh x\u00e1c tuy\u1ec7t \u0111\u1ed1i. H\u1ea7u h\u1ebft c\u00e1c k\u1ef9 s\u01b0 \u0111\u1ec1u nh\u1eadn ra r\u1eb1ng trong b\u1ed1i c\u1ea3nh c\u00f4ng nghi\u1ec7p H\u00e0 Lan, th\u1eddi gian ng\u1eebng ho\u1ea1t \u0111\u1ed9ng kh\u00f4ng \u0111\u01b0\u1ee3c t\u00ednh b\u1eb1ng ph\u00fat; m\u00e0 \u0111\u01b0\u1ee3c t\u00ednh b\u1eb1ng h\u00e0ng ngh\u00ecn Euro thi\u1ec7t h\u1ea1i do h\u00e0ng h\u00f3a d\u1ec5 h\u01b0 h\u1ecfng. \u0110\u00f3 l\u00e0 l\u00fd do t\u1ea1i sao ch\u00fang t\u00f4i t\u1eadp trung v\u00e0o c\u00e1c tr\u1ee5c Cardan hi\u1ec7u su\u1ea5t cao \u0111\u01b0\u1ee3c thi\u1ebft k\u1ebf \u0111\u1eb7c bi\u1ec7t cho c\u00e1c chu k\u1ef3 gia t\u1ed1c t\u1ea7n s\u1ed1 cao, qu\u00e1n t\u00ednh th\u1ea5p c\u1ee7a c\u00e1c d\u00e2y chuy\u1ec1n \u0111\u00f3ng g\u00f3i.<\/p>\n

\"Tr\u1ee5c<\/div>\n

T\u1ed5ng quan v\u1ec1 c\u00f4ng ngh\u1ec7 c\u1ed1t l\u00f5i: C\u00e1c y\u1ebfu t\u1ed1 thi\u1ebft y\u1ebfu c\u1ee7a h\u1ec7 th\u1ed1ng truy\u1ec1n \u0111\u1ed9ng m\u00e1y \u0111\u00f3ng th\u00f9ng carton<\/h2>\n

Nguy\u00ean l\u00fd c\u01a1 h\u1ecdc c\u1ee7a m\u00e1y \u0111\u00f3ng h\u1ed9p ho\u1eb7c m\u00e1y chi\u1ebft r\u00f3t \u0111\u00f2i h\u1ecfi tr\u1ee5c truy\u1ec1n \u0111\u1ed9ng ph\u1ea3i ch\u1ecbu \u0111\u01b0\u1ee3c s\u1ef1 \u0111\u1ea3o chi\u1ec1u m\u00f4-men xo\u1eafn t\u1ee9c th\u1eddi. Khi m\u00e1y quay, tr\u1ee5c s\u1ebd ch\u1ecbu m\u1ed9t xung l\u1ef1c c\u00f3 th\u1ec3 d\u1ec5 d\u00e0ng v\u01b0\u1ee3t qu\u00e1 \u0111\u1ecbnh m\u1ee9c n\u1ebfu qu\u00e1n t\u00ednh kh\u00f4ng \u0111\u01b0\u1ee3c t\u00ednh to\u00e1n ch\u00ednh x\u00e1c. Ch\u00fang t\u00f4i s\u1eed d\u1ee5ng th\u00e9p h\u1ee3p kim 42CrMo4 cho c\u00e1c kh\u1edbp n\u1ed1i, k\u1ebft h\u1ee3p v\u1edbi c\u00e1c r\u00e3nh then \u0111\u01b0\u1ee3c t\u00f4i c\u1ee9ng b\u1eb1ng c\u1ea3m \u1ee9ng \u0111\u1ec3 \u0111\u1ea3m b\u1ea3o r\u1eb1ng ngay c\u1ea3 sau 10 tri\u1ec7u chu k\u1ef3, v\u1eabn kh\u00f4ng c\u00f3 \u0111\u1ed9 r\u01a1 trong c\u1ee5m l\u1eafp r\u00e1p. \u0110\u1ed1i v\u1edbi c\u00e1c \u1ee9ng d\u1ee5ng th\u1ef1c ph\u1ea9m \u0111\u1ea1t ti\u00eau chu\u1ea9n H\u00e0 Lan, ch\u00fang t\u00f4i cung c\u1ea5p c\u00e1c t\u00f9y ch\u1ecdn m\u1ea1 niken kh\u00f4ng \u0111i\u1ec7n ph\u00e2n ho\u1eb7c ho\u00e0n to\u00e0n b\u1eb1ng th\u00e9p kh\u00f4ng g\u1ec9 \u0111\u1ec3 ch\u1ecbu \u0111\u01b0\u1ee3c vi\u1ec7c r\u1eeda b\u1eb1ng \u00e1p su\u1ea5t cao m\u1ea1nh m\u1ebd th\u01b0\u1eddng th\u1ea5y trong c\u00e1c nh\u00e0 m\u00e1y s\u1ea3n xu\u1ea5t s\u1eefa v\u00e0 \u0111\u1ed3 u\u1ed1ng.<\/p>\n

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B\u1ea3ng th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt: D\u00f2ng s\u1ea3n ph\u1ea9m bao b\u00ec ch\u00ednh x\u00e1c<\/h3>\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n
Danh m\u1ee5c tham s\u1ed1<\/th>\nTh\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt c\u00f4ng nghi\u1ec7p<\/th>\nDanh m\u1ee5c tham s\u1ed1<\/th>\nTh\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt c\u00f4ng nghi\u1ec7p<\/th>\n<\/tr>\n<\/thead>\n
M\u00f4-men xo\u1eafn \u0111\u1ecbnh m\u1ee9c (Nm)<\/td>\n150 \u2013 4.500 Nm<\/td>\nM\u1ee9c c\u00e2n b\u1eb1ng \u0111\u1ed9ng<\/td>\nISO 1940 G6.3 \/ G2.5<\/td>\n<\/tr>\n
T\u1ed1c \u0111\u1ed9 quay t\u1ed1i \u0111a<\/td>\n6.000 v\u00f2ng\/ph\u00fat<\/td>\nLo\u1ea1i Spline<\/td>\n\u0110\u01b0\u1eddng cong xo\u1eafn \u1ed1c DIN 5480<\/td>\n<\/tr>\n
C\u1ea5p \u0111\u1ed9 v\u1eadt li\u1ec7u (G\u1ecdng)<\/td>\nTh\u00e9p r\u00e8n 42CrMo4<\/td>\nH\u00e0nh tr\u00ecnh thu g\u1ecdn<\/td>\n50mm \u2013 400mm T\u00f9y ch\u1ec9nh<\/td>\n<\/tr>\n
G\u00f3c ho\u1ea1t \u0111\u1ed9ng (T\u1ed1i \u0111a)<\/td>\n25 \u0111\u1ed9<\/td>\n\u0110\u1ed9 c\u1ee9ng xo\u1eafn<\/td>\nCao (Gi\u1ea3m thi\u1ec3u hi\u1ec7n t\u01b0\u1ee3ng l\u00ean d\u00e2y c\u00f3t)<\/td>\n<\/tr>\n
V\u1eadt li\u1ec7u ni\u00eam phong<\/td>\nViton Multi-Lip<\/td>\nB\u1ea3o v\u1ec7 ch\u1ed1ng \u0103n m\u00f2n<\/td>\nK\u1ebdm Niken \/ Niken kh\u00f4ng \u0111i\u1ec7n ph\u00e2n<\/td>\n<\/tr>\n
Tu\u1ed5i th\u1ecd \u1ed5 tr\u1ee5c (L10)<\/td>\n20.000 gi\u1edd ho\u1ea1t \u0111\u1ed9ng<\/td>\nKh\u1ea3 n\u0103ng ch\u1ecbu \u0111\u1ef1ng ph\u1ea3n \u1ee9ng ng\u01b0\u1ee3c<\/td>\n< 0,05 \u0111\u1ed9<\/td>\n<\/tr>\n
\u0110\u1ed9 d\u00e0y th\u00e0nh \u1ed1ng<\/td>\n4,5mm \u2013 12,5mm<\/td>\nK\u1ebft n\u1ed1i m\u1eb7t b\u00edch<\/td>\nDIN\/ISO r\u0103ng ch\u00e9o<\/td>\n<\/tr>\n
M\u00f4men qu\u00e1n t\u00ednh<\/td>\nTh\u1ea5p (T\u1ed1i \u01b0u h\u00f3a cho Servo)<\/td>\nTi\u00eau chu\u1ea9n ch\u1ea5t b\u00f4i tr\u01a1n<\/td>\nH1 T\u1ed5ng h\u1ee3p d\u00f9ng trong th\u1ef1c ph\u1ea9m<\/td>\n<\/tr>\n
\u0110\u01b0\u1eddng k\u00ednh kh\u1edbp ch\u1eef U<\/td>\n58mm \u2013 180mm<\/td>\nC\u00f4ng ngh\u1ec7 h\u00e0n<\/td>\nH\u00e0n ma s\u00e1t b\u1eb1ng robot<\/td>\n<\/tr>\n
\u0110\u1ed9 c\u1ee9ng (V\u00f9ng ch\u1ecbu l\u1ef1c)<\/td>\nHRC 58-62<\/td>\nH\u01b0\u1edbng l\u1eafp \u0111\u1eb7t<\/td>\nN\u1eb1m ngang \/ Nghi\u00eang<\/td>\n<\/tr>\n
S\u1ee9c m\u1ea1nh va \u0111\u1eadp<\/td>\n350 J\/cm2<\/td>\nGi\u1ea3m ch\u1ea5n rung \u0111\u1ed9ng<\/td>\nT\u00f9y ch\u1ecdn ch\u1ea5t \u0111\u00e0n h\u1ed3i t\u00edch h\u1ee3p<\/td>\n<\/tr>\n
Ch\u1ea1y ra \u0111\u1ed9ng<\/td>\n< 0,15mm<\/td>\nKho\u1ea3ng th\u1eddi gian b\u1ea3o d\u01b0\u1ee1ng<\/td>\n5.000 gi\u1edd (Th\u1ee7 c\u00f4ng)<\/td>\n<\/tr>\n
H\u1ec7 s\u1ed1 an to\u00e0n<\/td>\nT\u1ea3i tr\u1ecdng t\u0129nh 3,5 l\u1ea7n<\/td>\nT\u00f9y ch\u1ecdn \u1ed5 tr\u1ee5c trung t\u00e2m<\/td>\nTr\u1ee5c b\u00e1nh xe cao su t\u1ef1 c\u0103n ch\u1ec9nh<\/td>\n<\/tr>\n
Ph\u1ea1m vi chi\u1ec1u d\u00e0i t\u00f9y ch\u1ec9nh<\/td>\n150mm \u2013 4000mm<\/td>\nT\u1ed1i \u01b0u h\u00f3a tr\u1ecdng l\u01b0\u1ee3ng<\/td>\nThi\u1ebft k\u1ebf tr\u1ee5c r\u1ed7ng<\/td>\n<\/tr>\n
L\u1edbp ph\u1ee7 Spline<\/td>\nNylon-11 \/ Rilsan<\/td>\nCh\u1ee9ng nh\u1eadn an to\u00e0n<\/td>\nCE \/ NEN ISO 12100<\/td>\n<\/tr>\n
Ph\u1ea1m vi nhi\u1ec7t \u0111\u1ed9 m\u00f4i tr\u01b0\u1eddng<\/td>\n-30\u00b0C \u0111\u1ebfn +120\u00b0C<\/td>\n\u0110\u01b0\u1eddng k\u00ednh v\u00f2ng bu l\u00f4ng<\/td>\n84mm \u2013 130mm<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n

[Noord-Brabant] Nghi\u00ean c\u1ee9u th\u1ef1c ti\u1ec5n \u0111\u1ed9 ch\u00ednh x\u00e1c cao: Kh\u00f4ng kh\u00ed c\u1ee7a Brainport<\/h2>\n

T\u1ea1i h\u00e0nh lang c\u00f4ng ngh\u1ec7 cao Eindhoven v\u00e0 Tilburg, \u0111\u1ed9 ch\u00ednh x\u00e1c c\u01a1 kh\u00ed \u0111\u01b0\u1ee3c coi tr\u1ecdng ngang b\u1eb1ng v\u1edbi c\u00f4ng ngh\u1ec7 in th\u1ea1ch b\u1ea3n b\u00e1n d\u1eabn. G\u1ea7n \u0111\u00e2y, ch\u00fang t\u00f4i \u0111\u00e3 h\u1ed7 tr\u1ee3 m\u1ed9t nh\u00e0 t\u00edch h\u1ee3p l\u1edbn c\u1ee7a H\u00e0 Lan chuy\u00ean v\u1ec1 m\u00e1y \u0111\u00f3ng g\u00f3i d\u01b0\u1ee3c ph\u1ea9m. Th\u00e1ch th\u1ee9c c\u1ee7a h\u1ecd? M\u1ed9t c\u01a1 c\u1ea5u chuy\u1ec3n \u0111\u1ed9ng \u0111\u1ecbnh v\u1ecb \u0111\u1ed9c quy\u1ec1n t\u1ea1o ra t\u1ea3i tr\u1ecdng va \u0111\u1eadp 4G trong giai \u0111o\u1ea1n x\u1ea3 li\u1ec7u. C\u00e1c tr\u1ee5c ti\u00eau chu\u1ea9n b\u1ecb g\u00e3y kh\u1edbp n\u1ed1i bu l\u00f4ng c\u1eaft sau m\u1ed7i v\u00e0i th\u00e1ng. D\u1ef1a tr\u00ean tr\u01b0\u1eddng h\u1ee3p th\u1ef1c t\u1ebf t\u1ea1i nh\u00e0 m\u00e1y k\u00e9o d\u00e0i 10 n\u0103m n\u00e0y, EVER-POWER \u0111\u00e3 thi\u1ebft k\u1ebf l\u1ea1i... K\u1ebft n\u1ed1i Spline-v\u1edbi-\u1ed1ng<\/strong> S\u1eed d\u1ee5ng c\u00f4ng ngh\u1ec7 h\u00e0n ma s\u00e1t khu\u1ea5y, t\u0103ng gi\u1edbi h\u1ea1n m\u1ecfi l\u00ean 40%.<\/p>\n

K\u1ebft qu\u1ea3 th\u1eadt \u0111\u00e1ng kinh ng\u1ea1c. Kh\u00f4ng ch\u1ec9 tu\u1ed5i th\u1ecd c\u1ee7a bu l\u00f4ng c\u1eaft t\u0103ng g\u1ea5p m\u01b0\u1eddi l\u1ea7n, m\u00e0 vi\u1ec7c gi\u1ea3m rung \u0111\u1ed9ng c\u00f2n cho ph\u00e9p kh\u00e1ch h\u00e0ng t\u0103ng t\u1ed1c \u0111\u1ed9 m\u00e1y t\u1eeb 280 l\u00ean 350 th\u00f9ng m\u1ed7i ph\u00fat m\u00e0 kh\u00f4ng l\u00e0m gi\u1ea3m \u0111\u1ed9 ch\u00ednh x\u00e1c c\u1ee7a nh\u00e3n. \u0110\u1ed1i v\u1edbi th\u1ecb tr\u01b0\u1eddng H\u00e0 Lan, n\u01a1i chi ph\u00ed nh\u00e2n c\u00f4ng cao v\u00e0 n\u0103ng su\u1ea5t l\u00e0 y\u1ebfu t\u1ed1 quan tr\u1ecdng h\u00e0ng \u0111\u1ea7u, \u0111\u00e2y ch\u00ednh l\u00e0 s\u1ef1 kh\u00e1c bi\u1ec7t gi\u1eefa m\u1ed9t d\u00e2y chuy\u1ec1n s\u1ea3n xu\u1ea5t c\u00f3 l\u1ee3i nhu\u1eadn v\u00e0 m\u1ed9t \u0111i\u1ec3m ngh\u1ebdn. \"B\u00e0n tay k\u1ef9 s\u01b0\" c\u1ee7a ch\u00fang t\u00f4i c\u00f3 ngh\u0129a l\u00e0 ch\u00fang t\u00f4i xem x\u00e9t qu\u00e1n t\u00ednh c\u1ee5 th\u1ec3 c\u1ee7a t\u1ea3i tr\u1ecdng c\u1ee7a b\u1ea1n, ch\u1ee9 kh\u00f4ng ch\u1ec9 l\u00e0 bi\u1ec3u \u0111\u1ed3 m\u00f4-men xo\u1eafn chung chung. N\u1ebfu d\u00e2y chuy\u1ec1n c\u1ee7a b\u1ea1n n\u1eb1m trong khu v\u1ef1c Brainport, b\u1ea1n bi\u1ebft r\u1eb1ng \"\u0111\u1ee7 t\u1ed1t\" kh\u00f4ng bao gi\u1edd l\u00e0 \u0111\u1ee7 t\u1ed1t.<\/p>\n

\"tr\u1ee5c<\/p>\n

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T\u00f3m t\u1eaft c\u00e1c y\u1ebfu t\u1ed1 quan tr\u1ecdng c\u1ea7n xem x\u00e9t khi l\u1ef1a ch\u1ecdn h\u1ec7 th\u1ed1ng \u0111i\u1ec7n: Ma tr\u1eadn quy\u1ebft \u0111\u1ecbnh c\u1ee7a chuy\u00ean gia<\/h2>\n