谁知道[img]http://[/img][url=http://]http://www.taobao.com/view_image.php?pic=Wx0GGlFDXA1VUwMDWx0SCwkNGRFcVxxQW1UcCxMFRBkDCFdVV1cRRhpVRF1GSwsBAgEDAQRcR11ZX0tVF2ACcC8GKzwBJh8qYGFqa2xgazZTS1tBGhBdWWxCHApdDhsL&title=MrSuMTg2NTC157PY1sfE3Ma9uuKz5LXnxvcrsaO7pLDlNy40Vi44LjRWINGw0MfSx8a9uuKz5LXn&version=2&c=Mjc5M2JjMGU3MDQwMWJkNDg3ZTE0ZGUzM2UwNTdjZTk%3D&itemId=21368392139&shopId=61823959&sellerRate=1144&dbId=&fv=9[/url]的原理图呀