treadle operated valve踏板: footstep; footboard; balance ...操作阀: operating valve踏板操: step双踏板操纵: two pedal operation踏板操纵的: pedal-operated下载手机词典可随时随地查词查翻译关注微信公众号：chachacidian，回复:踏板操作阀，即可在微信中查询翻译
