A.鍵深 B.鍵寬 C.鍵長(zhǎng)
A.蝸輪 B.蝸桿 C.蝸桿傳動(dòng)副
A.對(duì)稱(chēng)雙角 B.對(duì)稱(chēng)單角 C.不對(duì)稱(chēng)單角