已知p=10KW,小 链轮的转速n1=720r/min,传动比i=2.8,载荷平稳,两班工作制,两链轮中心距a=500~600mm范围,中心距可调,两轮中心连线与水平面夹角近于35o,小链轮孔径  。 计算: (1)小链轮齿数z1 z1=29-2i=29-2*2.8=23.4 取整数z1=23 i | 1~2 | 2~3 | 3~4 | 4~5 | 5~6 | 6 | z1 | 31~27 | 27~25 | 25~23 | 23~21 | 21~17 | 17~15 | ! d( }; |2 l6 Q4 f3 N7 }
| 优先选用齿数:17,19,21,23,25,38,57,76,95,114 |
z1、z2取奇数,则链条节数  为偶数时,可使链条和链轮轮齿磨损均匀。在高速或有冲击载荷的情况下,小链轮齿最小应有25齿。 (2)大链轮齿数z2 Z2=iz1=2.8*23=64.4 取整z2=65 (3)实际传动比i=  (5)单排链条传递功率  ,查表5.4-4和5.4-5,齿数系数  ,排数系数  =1  =8.13kw (6)链节距p 根据  ,n1=720r/min,查图5.4-1功率曲线  和n1确定的点,应在所选型号链的功率曲线下方附近(不超过直线)。结果为10A,节距p=15.875mm, (7)验算小链轮 轴直径  查5.4-7链轮中心孔最大许用直径  (8)初定中心距   为优,无张紧轮时取  i | <4 | ≥4 | | 0.2z1(i+1)p | 0.33z1(i-1)p |
1 N0 h2 \2 O: X( E(9)确定链条节数   =115.3 取  (10)链条长度  (11)计算(理论)中心距  当  时,  当  时,  根据  ,查表5.4-9,若有必要可使用插值。 (12)实际中心距a  ,一般  (13)链速  (14)有效圆周率  (15)作用在轴上的力F 水平或倾斜的传动  接近垂直的传动   工况系数,见表5.4-3 F=1.2×1×2283.1=2739.7N (16)润滑方式。 (17)链条标记:10A-1-116 GB 1243-1997 1表示排数,116表示节数 (18)链轮的几何尺寸 滚子直径  p=15.875mm 1)分度圆直径  小链轮  ,大链轮  2)齿顶圆   ,  对于三圆弧-直线齿形  小链轮齿顶圆  =124.072mm,取整124mm 大链轮齿顶圆  =336.773mm,取整337mm 3)齿根圆直径  小链轮齿根圆直径  = 116.585-10.16=106.425mm,取106.43mm 大链轮齿根圆直径  = 328.584-10.16=318.424mm,取318.42 mm 4)节距多变形以上的齿高  =0.27×15.875=4.286mm(对于三圆弧-直线齿形) 5)最大齿根距  奇数齿  偶数齿  小链轮  =106.153mm 大链轮  =318.328mm 6)轴凸缘直径  小链轮  =99.045mm 大链轮  =311.746mm 7)轮毂厚度h  ,  ——孔的直径 d | <50 | 50~100 | 100~150 | >150 | K | 3.2 | 4.8 | 6.4 | 9.5 |
小链轮  =14.232,取整14mm 大链轮  =22.7858,取整数22mm 8)轮毂长度l l=3.3h  小链轮l=3.3×14=46.2mm,取整46mm 大链轮l=3.3×22=72.6mm,取整72mm 9)轮毂直径  ,  小链轮  =68mm 大链轮  =104mm 10)齿宽  单排  单排  =0.95×9.4=8.93mm 11)齿侧半径  12)倒角宽   ,取2.1mm 13)倒角深h=0.5p=0.5×15.875=7.9375mm 14)齿侧凸缘圆角半径  =0.635mm (19)链轮公差 1)齿根圆直径和量柱测量距极限偏差 项 目 | 极限偏差 | 孔径  | H8 | 齿顶圆  | h11 | 齿根圆直径  极限偏差 | h11 | 齿宽  | h14 | 量柱测量距  极限偏差 | h11 | - M9 f& Q( l ~" l* P& m5 W
" `/ A1 W" q1 N$ K' z, B
小链轮齿根圆直径  = 116.585-10.16=106.425mm,取106.43mm 大链轮齿根圆直径  = 328.584-10.16=318.424mm,取318.42 mm  ,  小链轮量柱测量距  大链轮量柱测量距  2)径向圆跳动 小链轮径向圆跳动=min{0.0008df+0.008,0.76}=0.0008×106.43+0.008=0.093144 端面跳动=min{0.0009df+0.008,1.14}
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