A.i=n1/n2=z2/z1=d2/d B.i=n1/n2=z2/z1 C.i=n1/n2=z2/q D.以上選項(xiàng)都不對(duì)
對(duì)于經(jīng)常正反轉(zhuǎn)的直齒圓柱齒輪傳動(dòng),進(jìn)行齒面接觸疲勞強(qiáng)度計(jì)算時(shí),若,則接觸許用應(yīng)力應(yīng)取為()
A. B. C. D.