设计直齿圆柱齿轮

1、计算项目计算内容计算结果设计单级直齿圆柱齿轮减速器中的齿轮传动。已知传动功率P=7.5kw，小齿轮转速n1=970r/min，大齿轮转速n2=250r/min;电动机驱动，工作载荷比较平稳，单向传动，小齿轮齿数Z1=25。小齿轮选45钢调质210HBS，大齿轮材料选45钢正火180HBS。1选材小齿轮 45 调质 210HBS大齿轮 45 正火 180HBS2确定许用应力h f由图7-23 h1lim=550MPa h2lim=530MPa由图7-25 f1lim=190MPa f2lim=170MPa设齿轮工作寿命为10年N=10*250*8*60*970=1.164*109由图7-24 Z

2、n=1由图7-26 Yn=1由表7-5 Sf=1 Sf=1.35h1=Znh1lim/Sh h2=Znh2lim/Sh =1*550/1 =1*530/1 =550MPa =530MPaf1=Ynf1lim/Sf f2=Ynf2lim/Sf =1*190/1.35 =1*170/1.35 =141MPa =126MPah1=550MPah2=530MPaf1=141MPaf2=126MPa3确定精度等级i=n1/n2=3.88=<5m/s选8级精度i=<5m/s4确定计算载荷T1=9.55*106P/n1 T2=9.55X106P/n2 =9.55*106*7.5/970 =9.5

3、5*106*7.5/250 =7.4*104Nmm =2.865*105NmmT1=7.4X104NmmT2=2.865X105Nmm5定载荷系数由表7-6 K=1由表7-7 Ze=189.8MPaK=1Ze=189.8MPa6确定齿宽系数由表7-8 d=1d=17确定d1d1经公式计算得d1=51.4mm8调整基本参数由题Z1=25 则m=d1/z1 d1=mz1由题m=2.5 =51.4/25 =2.5*25 =2.056 =62.5mmd2=mZ2 =mZ1 =2.5*25*3.88 =242.5mm d1=62.5mmd2=242.5mm9计算齿轮主要尺寸ha1=ha2=ha*m=1*

4、2.5=2.5mmhf1=hf2=ha*+c*m=1+0.25*2.5=3.125mmh1=h2=ha1+hf1=2.5+3.125=5.625mmc1=c2=c*m=0.25*2.5=0.625mmda1=d1+2ha1=62.5+2*2.5=67.5mmda2=d2+2ha1=242.5+2*2.5=247.5mmdf1=d1-2hf1=62.5-2*3.125=56.25mmdf2=d2-2hf1=242.5-2*3.125=236.25mmP1=P2=m=3.14*2.5=7.85mms1=s2=m/2=3.925mme1=e2=m/2=3.925mma=mZ1+Z2/2=2.525+

5、100/2=156.25mmha1=ha2=2.5mmhf1=hf2=3.125mmc1=c2=0.625mmda1=67.5mmda2=247.5mmdf1=56.25mmdf2=236.25mmP1=P2=7.85mms1=s2=3.925mme1=e2=3.925mma=156.25mm10验算齿轮弯曲强度d=b/d1=1 b=d1=62.5mm由表7-9 Yf1=2.65 Ys1=1.59f1=2KT1/bm2Z1Yf1Ys1<=f1=2*1*7.4*104/62.6*2.52*25*2.65*1.59=63.86MPa<=f1Z2=Z1=25*3.88=97则Z2=100由表7-9 Yf2=2.18 Ys2=1.80f2=2KT2/bm2Z2Yf2Ys2<=f2=2*1*.86