1 00:00:00,308 --> 00:00:01,748 O joo de enrenaens planetárias 2 00:00:01,748 --> 00:00:02,718 também conecido como, 3 00:00:02,718 --> 00:00:04,256 a enrenaens epicíclica 4 00:00:04,256 --> 00:00:05,260 é uma das 5 00:00:05,260 --> 00:00:06,470 mais importantes 6 00:00:06,470 --> 00:00:08,350 invençoes da enenaria. 7 00:00:08,350 --> 00:00:09,490 Sao ótimos mecanismos 8 00:00:09,490 --> 00:00:10,811 para variaçao de velocidade e torque 9 00:00:10,811 --> 00:00:11,882 e sao frequentemente usados 10 00:00:11,882 --> 00:00:13,813 em automóveis como parte vital 11 00:00:13,813 --> 00:00:15,233 das transmissoes automáticas. 12 00:00:18,585 --> 00:00:19,967 Vamos explorar os seredos 13 00:00:19,967 --> 00:00:21,234 das enrenaens 14 00:00:21,234 --> 00:00:22,834 neste vídeo! 15 00:00:24,664 --> 00:00:26,129 O joo de enrenaens 16 00:00:26,129 --> 00:00:28,029 tem 4 partes principais: 17 00:00:28,479 --> 00:00:30,038 a enrenaem solar, 18 00:00:30,368 --> 00:00:31,897 as portas planetárias, 19 00:00:32,867 --> 00:00:34,537 a enrenaem anelar, 20 00:00:35,537 --> 00:00:37,140 e o braço. 21 00:00:37,405 --> 00:00:38,408 Podemos ver que elas 22 00:00:38,408 --> 00:00:40,528 podem irar rapidamente, 23 00:00:41,708 --> 00:00:43,882 ou mais de devaar, 24 00:00:46,023 --> 00:00:47,283 até mesmo em marca reversa. 25 00:00:47,283 --> 00:00:48,873 Mas, como isso acontece? 26 00:00:50,203 --> 00:00:52,494 Voce será capaz 27 00:00:52,494 --> 00:00:53,474 de prever o movimento 28 00:00:53,474 --> 00:00:54,514 das enrenaens por comcompleto, 29 00:00:54,514 --> 00:00:55,896 se entender 30 00:00:55,896 --> 00:00:56,836 um fato simples. 31 00:00:56,836 --> 00:00:58,473 quando duas enrenaens 32 00:00:59,123 --> 00:01:00,273 esao se movendo, veja, 33 00:01:00,273 --> 00:01:01,522 elas devem estar na 34 00:01:01,522 --> 00:01:02,362 mesma velocidade 35 00:01:02,362 --> 00:01:03,362 do eixo. 36 00:01:03,362 --> 00:01:04,943 Isso sinifica 37 00:01:04,943 --> 00:01:06,073 que a velocidade da enrenaem A 38 00:01:06,073 --> 00:01:07,503 deve ser a mesma 39 00:01:07,503 --> 00:01:08,494 que a da enrenaem B, 40 00:01:08,494 --> 00:01:09,493 no seu ponto de encontro. 41 00:01:09,493 --> 00:01:11,393 A velocidade tem que ser 42 00:01:17,139 --> 00:01:18,409 a mesma, ou 43 00:01:18,409 --> 00:01:19,322 os dentes da enrenaem 44 00:01:19,322 --> 00:01:20,302 irao encontrar uns aous outros 45 00:01:20,302 --> 00:01:21,321 desta forma. 46 00:01:21,321 --> 00:01:22,340 Tornando a situaçao impossível. 47 00:01:22,340 --> 00:01:23,550 Aplicando esta correçao 48 00:01:23,550 --> 00:01:25,806 nas enrenaens planetárias, 49 00:01:26,818 --> 00:01:28,108 voce poderá ver 50 00:01:28,108 --> 00:01:29,540 como a variaçao velocidade 51 00:01:29,540 --> 00:01:31,024 será alcançada, 52 00:01:31,024 --> 00:01:32,434 No momento a enrenaem solar 53 00:01:32,434 --> 00:01:34,124 está na posiçao imóvel 54 00:01:35,864 --> 00:01:37,254 e a enrenaem solar ira. 55 00:01:37,254 --> 00:01:38,374 Pense no que acontece 56 00:01:38,374 --> 00:01:40,280 as enrenaens planetárias. 57 00:01:43,930 --> 00:01:45,168 No ponto A 58 00:01:45,168 --> 00:01:46,858 a enrenaem solar 59 00:01:47,968 --> 00:01:48,968 deve estar a uma determinada velocidade 60 00:01:48,968 --> 00:01:49,968 e no ponto B 61 00:01:49,968 --> 00:01:51,746 a velocidade deverá ser zero, 62 00:01:51,746 --> 00:01:53,123 pois a enrenaem anelar ou externa 63 00:01:53,123 --> 00:01:54,343 está estacionada ou imóvel. 64 00:01:54,343 --> 00:01:55,343 No entanto, 65 00:01:55,343 --> 00:01:56,963 como estas duas situaçoes 66 00:01:56,963 --> 00:01:57,741 sao possíveis ao mesmo tempo? 67 00:01:57,741 --> 00:01:58,531 Só á uma explicaçao, 68 00:01:58,531 --> 00:01:59,511 a enrenaem planeta 69 00:02:01,751 --> 00:02:03,661 deverá irar e ao mesmo tempo virar! 70 00:02:03,661 --> 00:02:04,801 A rotaçao irá produzir 71 00:02:04,801 --> 00:02:07,556 velocidades em direçoes opostos 72 00:02:07,556 --> 00:02:08,843 nos pontos de cima e de baixo, 73 00:02:08,843 --> 00:02:10,803 veja, 74 00:02:10,803 --> 00:02:12,273 enquanto, a virada 75 00:02:12,273 --> 00:02:13,723 produz velocidades unidirecionais. 76 00:02:13,723 --> 00:02:14,993 Em cima, as velocidades 77 00:02:14,993 --> 00:02:17,523 de rtoaçao e virada 78 00:02:18,853 --> 00:02:19,872 estao em direçoes opostas, 79 00:02:19,872 --> 00:02:21,602 assim, a velocidade do 80 00:02:21,602 --> 00:02:23,451 ponto B é zero. 81 00:02:23,451 --> 00:02:24,451 Em baixo. 82 00:02:24,451 --> 00:02:25,930 elas se somam. 83 00:02:26,460 --> 00:02:27,333 Nas pequenas 84 00:02:27,333 --> 00:02:29,053 enrenaens planetárias 85 00:02:29,783 --> 00:02:30,781 sao forçadas a virar 86 00:02:30,781 --> 00:02:31,941 para compensar a exiencia 87 00:02:31,941 --> 00:02:33,192 da velocidade encontrada. 88 00:02:33,192 --> 00:02:34,372 Quando o braço é liado 89 00:02:34,372 --> 00:02:36,024 as enrenaens planetárias 90 00:02:36,024 --> 00:02:37,506 ele irá virar juntamente com 91 00:02:37,506 --> 00:02:38,966 as enrenaens planetas. 92 00:02:38,966 --> 00:02:40,185 Aora, vejamos o que acontece 93 00:02:40,185 --> 00:02:42,074 quando a enrenaem solar 94 00:02:42,674 --> 00:02:44,056 está travada 95 00:02:44,056 --> 00:02:45,137 e a enrenaem anelar 96 00:02:45,137 --> 00:02:46,290 é irada. 97 00:02:46,290 --> 00:02:47,343 O exato oposto ao caso anterior. 98 00:02:47,343 --> 00:02:48,833 No ponto interno 99 00:02:50,363 --> 00:02:51,743 da enrenaem planeta 100 00:02:51,743 --> 00:02:53,560 101 00:02:53,560 --> 00:02:54,266 102 00:02:54,266 --> 00:02:55,490 103 00:02:55,490 --> 00:02:57,150 104 00:02:57,150 --> 00:02:58,489 105 00:02:58,489 --> 00:02:59,729 106 00:02:59,729 --> 00:03:00,978 107 00:03:00,978 --> 00:03:02,165 108 00:03:02,165 --> 00:03:03,225 109 00:03:03,225 --> 00:03:04,650 110 00:03:04,650 --> 00:03:05,169 111 00:03:05,169 --> 00:03:06,972 112 00:03:08,722 --> 00:03:09,590 113 00:03:09,590 --> 00:03:10,280 114 00:03:10,280 --> 00:03:11,958 115 00:03:11,958 --> 00:03:13,546 116 00:03:13,546 --> 00:03:14,516 117 00:03:14,516 --> 00:03:16,128 118 00:03:16,128 --> 00:03:17,850 119 00:03:17,850 --> 00:03:18,973 120 00:03:18,973 --> 00:03:20,763 121 00:03:20,763 --> 00:03:22,183 122 00:03:25,949 --> 00:03:26,869 123 00:03:26,869 --> 00:03:28,142 124 00:03:28,142 --> 00:03:30,272 125 00:03:30,272 --> 00:03:31,914 126 00:03:31,914 --> 00:03:34,136 127 00:03:36,364 --> 00:03:37,560 128 00:03:37,560 --> 00:03:39,060 129 00:03:39,060 --> 00:03:40,190 130 00:03:42,360 --> 00:03:43,177 131 00:03:43,177 --> 00:03:44,197 132 00:03:44,197 --> 00:03:45,220 133 00:03:45,220 --> 00:03:47,533 134 00:03:47,733 --> 00:03:48,829 135 00:03:48,829 --> 00:03:49,659 136 00:03:49,659 --> 00:03:51,106 137 00:03:51,106 --> 00:03:52,903 138 00:03:54,683 --> 00:03:56,313 139 00:03:56,313 --> 00:03:58,843 140 00:03:59,233 --> 00:04:00,721 141 00:04:00,721 --> 00:04:02,121 142 00:04:02,121 --> 00:04:04,521 143 00:04:04,521 --> 00:04:05,897 144 00:04:05,897 --> 00:04:07,267 145 00:04:07,267 --> 00:04:08,411 146 00:04:08,411 --> 00:04:09,481 147 00:04:09,481 --> 00:04:10,558 148 00:04:10,558 --> 00:04:12,495 149 00:04:14,905 --> 00:04:16,002 150 00:04:16,002 --> 00:04:17,596 151 00:04:17,596 --> 00:04:18,732 152 00:04:18,732 --> 00:04:20,990 153 00:04:20,990 --> 00:04:21,604 154 00:04:21,604 --> 00:04:23,639 155 00:04:25,394 --> 00:04:26,622 156 00:04:26,622 --> 00:04:27,851 157 00:04:27,851 --> 00:04:30,303 158 00:04:30,303 --> 00:04:32,756 159 00:04:32,756 --> 00:04:33,756 160 00:04:33,756 --> 00:04:36,443 161 00:04:36,443 --> 00:04:39,130 162 00:04:39,130 --> 00:04:40,130 163 00:04:40,130 --> 00:04:41,641 164 00:04:41,641 --> 00:04:42,648 165 00:04:42,648 --> 00:04:43,319 166 00:04:43,319 --> 00:04:43,767 167 00:04:43,767 --> 00:04:44,215 168 00:04:44,215 --> 00:04:46,120 169 00:04:46,120 --> 00:04:47,810