•标准链轮的尺寸P：节距,R：滚子直径,N:链轮的齿数◎节距直径PCD=P/（sin180°/N）◎外径OD=P/（0.6+cot180°/N）下表给出一种标准节距链轮的节距直径和外径（节距1）。例：为了得到120号NT（齿数）25链轮的节径和外径从表中可得到节距为7.9789。因此PCD=38.1x7.9789=303.98847，或者取小数点后1位并四舍五入303.99。夕卜径可从表中查得为8.516。因此OD=38.10x8.516=324.4596，或取小数点后1位并四舍五入324。齿根圆直径BD=PCD—R最大齿根距离（卡钳测量）:CD对于奇数齿：CD=PCDcos90/N—R对于偶数齿：CD=BD奇散齿偶数彗拥Jf:^JJJ标准琏轮尺寸链轮标准规格尺寸一览表齿数i系数系数齿数i系数系数齿数系数系数1/[sin(180.6+cot(11/[sin(18016+cot(1/[sin(180.6+cot(10/N)]80/N)0/N)]180/N)0/N)]80/N)13.54954.006516.244116.813928.97229.2912113.86374.332516.562217.132929.290229.87322214.17864.657516.880317.451929.608530.19233314.4944.981517.198417.769929.926730.5144414.80975.305517.516618.088930.244930.82855515.12585.627517.834718.407930.563231.14766615.44225950518.152918.725930.881531.46577715.75886.271518.47119.044931.199731.78488816.07556593518.789219.363931.51832.102999126.39256914619.107319.681031.836232.4210002l6.70957.2356119.42552010132.154532.739127.02677.555619.743720.318032.472733.057222127.34397876620.061820.637032.79133.376333127.66138196620.3820.955033.109333.694444127.97878.516620.698221.274033.427534.013555128.29628.836621.016421.593033.745834.331666128.61389.156621.234921.911034.064134.69477728.93149.475621.652822.23134.382334.9688808129.24919.795621.97122.548034.700635.286999139.566810.114722.289222.867135.018935.605000139.884510.434722.607423.185135.337135.9231111310.202310.753722.925623.504135.655436.2412221310.520111.072723.243823.822135.973736.563331310.83811.392723.56224.141136.291936.878444311.155811.711723.880224.459136.610237.19755151311.473712.03724.198424778136.928537.5156661311.791612.349724.516725.096137.246737.8337771312.109612.668724.834925.415137.56538.1528881312.427512.987725.153125.733137.883338.479991412.745513.306825.471326.052238.201638.788000413.063513.625825.789626.3711413.381513.944826.107826.68922413.699514.363826.426127.007334414.017514.5828426.744327.3264514.3356149018527.062527.6444614.653615.2198627.380727.9624714.971715.5388727.69928.2814815.289815.8578828.017228.5994915.607916.1768928.335528.9185015.92616.4959028.653729.236
