減速機是(shi)(shi)一(yi)(yi)種常(chang)用減(jian)(jian)(jian)速(su)(su)設備(bei)，主(zhu)要(yao)結(jie)構由(you)傳(chuan)(chuan)動(dong)電機、齒(chi)輪(lun)箱（減(jian)(jian)(jian)速(su)(su)器(qi)）組裝而成，傳(chuan)(chuan)動(dong)效率(lv)，減(jian)(jian)(jian)速(su)(su)裝置取決于減(jian)(jian)(jian)速(su)(su)機齒(chi)輪(lun)箱的(de)(de)齒(chi)輪(lun)組嚙合級(ji)(ji)(ji)(ji)數(shu)，一(yi)(yi)個小齒(chi)輪(lun)帶動(dong)一(yi)(yi)個大(da)(da)齒(chi)輪(lun)進行(xing)減(jian)(jian)(jian)速(su)(su)時(shi)，稱之為一(yi)(yi)級(ji)(ji)(ji)(ji)減(jian)(jian)(jian)速(su)(su)器(qi)，當(dang)一(yi)(yi)級(ji)(ji)(ji)(ji)減(jian)(jian)(jian)速(su)(su)無法達到需(xu)(xu)求時(shi)，需(xu)(xu)要(yao)多級(ji)(ji)(ji)(ji)齒(chi)輪(lun)嚙合傳(chuan)(chuan)動(dong)來完成減(jian)(jian)(jian)速(su)(su)傳(chuan)(chuan)動(dong)需(xu)(xu)求，例如行(xing)星(xing)減(jian)(jian)(jian)速(su)(su)機一(yi)(yi)套行(xing)星(xing)齒(chi)輪(lun)（行(xing)星(xing)齒(chi)輪(lun)組由(you)太陽輪(lun)、行(xing)星(xing)輪(lun)、內齒(chi)圈組成）無法滿足較(jiao)大(da)(da)的(de)(de)傳(chuan)(chuan)動(dong)比，有時(shi)需(xu)(xu)要(yao)2套或者3套來滿足用戶較(jiao)大(da)(da)的(de)(de)傳(chuan)(chuan)動(dong)比的(de)(de)要(yao)求.由(you)于增(zeng)加了行(xing)星(xing)齒(chi)輪(lun)的(de)(de)數(shu)量，所以2級(ji)(ji)(ji)(ji)或3級(ji)(ji)(ji)(ji)減(jian)(jian)(jian)速(su)(su)機的(de)(de)長(chang)度(du)會(hui)有所增(zeng)加，效率(lv)會(hui)有所下降；減(jian)(jian)(jian)速(su)(su)機級(ji)(ji)(ji)(ji)數(shu)通(tong)常(chang)有單級(ji)(ji)(ji)(ji)、雙級(ji)(ji)(ji)(ji)、三級(ji)(ji)(ji)(ji)，但是(shi)(shi)有部分大(da)(da)減(jian)(jian)(jian)速(su)(su)比的(de)(de)可達到四級(ji)(ji)(ji)(ji)，級(ji)(ji)(ji)(ji)數(shu)越大(da)(da)減(jian)(jian)(jian)速(su)(su)傳(chuan)(chuan)動(dong)效率(lv)越低。

行(xing)星齒輪箱內部結(jie)構如下圖：