可动岔心 continuous-rail frog: 连续钢轨辙岔rail frog: 钢轨辙叉spring rail frog: 弹簧辙叉wing rail (of frog): 翼轨rail bound manganese steel frog: 钢轨组合锰钢叉心辙叉下载手机词典可随时随地查词查翻译