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 "worksheets": [
  {
   "cells": [
    {
     "cell_type": "heading",
     "level": 1,
     "metadata": {},
     "source": [
      "Ch:28 Worm and worm wheel set"
     ]
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "exa 28-1 - Page 726"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "from __future__ import division\n",
      "from math import sqrt, pi\n",
      "Z1=1#\n",
      "Z2=30#\n",
      "q=10#\n",
      "m=5#\n",
      "d=q*m#\n",
      "D=m*Z2#\n",
      "#let the speed reduction ratio be G\n",
      "G=Z2/Z1#\n",
      "CD=(d+D)/2#\n",
      "print \"G is %0.0f   \"%(G)#\n",
      "print \"\\nCD is %0.0f mm  \"%(CD)#\n",
      "print \"\\nd  is %0.0f mm  \"%(d)#\n",
      "print \"\\nD  is %0.0f mm  \"%(D)#"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "G is 30   \n",
        "\n",
        "CD is 100 mm  \n",
        "\n",
        "d  is 50 mm  \n",
        "\n",
        "D  is 150 mm  \n"
       ]
      }
     ],
     "prompt_number": 8
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "exa 28-2 - Page 726"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "from math import tan, atan, cos\n",
      "Z1=1#\n",
      "Z2=52#\n",
      "q=10#\n",
      "m=8#\n",
      "i=Z2/Z1#\n",
      "CD=((m*q)+(m*Z2))/2#\n",
      "lamda=atan(Z1/q)#\n",
      "d=q*m#\n",
      "da=m*(q+2)#\n",
      "df=m*(q+2-(4.4*cos(lamda)))#\n",
      "pa=m*pi#\n",
      "D=m*Z2#\n",
      "Da=m*(Z2+(4*cos(lamda))-2)#\n",
      "Df=m*(Z2-2-(0.4*cos(lamda)))#\n",
      "print \"i is %0.0f   \"%(i)#\n",
      "print \"\\nCD is %0.0f mm  \"%(CD)#\n",
      "print \"\\npa is %0.2f mm  \"%(pa)#\n",
      "print \"\\nda is %0.0f mm  \"%(da)#\n",
      "print \"\\ndf is %0.3f mm  \"%(df)#\n",
      "print \"\\nDa is %0.3f mm  \"%(Da)#\n",
      "print \"\\nDf is %0.3f mm  \"%(Df)#"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "i is 52   \n",
        "\n",
        "CD is 248 mm  \n",
        "\n",
        "pa is 25.13 mm  \n",
        "\n",
        "da is 96 mm  \n",
        "\n",
        "df is 60.975 mm  \n",
        "\n",
        "Da is 431.841 mm  \n",
        "\n",
        "Df is 396.816 mm  \n"
       ]
      }
     ],
     "prompt_number": 9
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "exa 28-3 - Page 727"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "from math import sin\n",
      "Z1=2#\n",
      "Z2=60#\n",
      "q=10#\n",
      "m=5#\n",
      "P=6000#\n",
      "N=1440#\n",
      "u=0.08#\n",
      "alpha=20*pi/180#\n",
      "lamda=atan(Z1/q)#\n",
      "d=m*q#\n",
      "w=2*pi*N/60#\n",
      "T=P/w#\n",
      "Ptw=T*10**3/(d/2)#\n",
      "a=cos(alpha)#\n",
      "b=cos(lamda)#\n",
      "x=sin(alpha)#\n",
      "y=sin(lamda)#\n",
      "Paw=Ptw*(((a*b)-(u*y))/((a*y)+(u*b)))#\n",
      "Prw=Ptw*y/((a*y)+(u*b))#\n",
      "#Paw=Ptw*((cos(alpha)*cos(lambda))-(u*sin(lambda)))/((cos(alpha)*sin(lambda))+(u*cos(lambda)))#\n",
      "#Prw=Ptw*((sin(alpha))/((cos(alpha)*sin(lambda))+(u*cos(lambda))))#\n",
      "print \"Ptw=Pag is %0.1f N  \"%(Ptw)#\n",
      "print \"\\nPaw=Ptg is %0.0f N  \"%(Paw)#\n",
      "print \"\\nPrw=Prg  is %0.0f N  \"%(Prw)#\n",
      "  \n",
      "#The difference in the value is due to rounding-off the values."
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Ptw=Pag is 1591.5 N  \n",
        "\n",
        "Paw=Ptg is 5487 N  \n",
        "\n",
        "Prw=Prg  is 1188 N  \n"
       ]
      }
     ],
     "prompt_number": 10
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "exa 28-4 - Page 728"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "Z1=2#\n",
      "Z2=40#\n",
      "q=8#\n",
      "m=5#\n",
      "d=q*m#\n",
      "P=1.2#\n",
      "lamda=atan(Z1/q)#\n",
      "N=1000#\n",
      "Vt=2*pi*N*20/(60*1000)#\n",
      "Vs=Vt/cos(lamda)#\n",
      "u=0.032#\n",
      "alpha=20*pi/180#\n",
      "x=cos(alpha)#\n",
      "y=tan(lamda)#\n",
      "z=(cos(lamda))/sin(lamda)#\n",
      "n=(x-(u*y))/(x+(u*z))#\n",
      "#Let power output be Po\n",
      "Po=P*n#\n",
      "#Let power lost in friction be Pf\n",
      "Pf=P-Po#\n",
      "print \"P is %0.1f kW  \"%(P)#\n",
      "print \"\\nPo is %0.3f kW  \"%(Po)#\n",
      "print \"\\nPf is %0.3f kW  \"%(Pf)#\n",
      "  "
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "P is 1.2 kW  \n",
        "\n",
        "Po is 1.047 kW  \n",
        "\n",
        "Pf is 0.153 kW  \n"
       ]
      }
     ],
     "prompt_number": 11
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "exa 28-5 - Page 729"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "Z1=2#\n",
      "Z2=54#\n",
      "q=10#\n",
      "m=8#\n",
      "P=4000#\n",
      "A=1.8#\n",
      "K=16#\n",
      "N=1000#\n",
      "u=0.028#\n",
      "lamda=atan(Z1/q)#\n",
      "alpha=20*pi/180#\n",
      "d=m*q#\n",
      "Vt=2*pi*N*d/(2*60*1000)#\n",
      "Vs=Vt/cos(lamda)#\n",
      "x=cos(alpha)#\n",
      "y=tan(lamda)#\n",
      "z=(cos(lamda))/sin(lamda)#\n",
      "n=(x-(u*y))/(x+(u*z))#\n",
      "delT=P*(1-n)/(K*A)#\n",
      "print \"n is %0.3f   \"%(n)#\n",
      "print \"\\ndelT is %0.2f deg  \"%(delT)#"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "n is 0.865   \n",
        "\n",
        "delT is 18.73 deg  \n"
       ]
      }
     ],
     "prompt_number": 12
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "exa 28-6 - Page 729"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "Z1=1#\n",
      "Z2=30#\n",
      "q=10#\n",
      "m=6#\n",
      "#Let the ultimate strength of gear is sigut\n",
      "#Let the allowable strenth of wheel is sigb\n",
      "sigut=450#\n",
      "sigb=84#\n",
      "N=1200#\n",
      "n=N/Z2#\n",
      "alpha=20*pi/180#\n",
      "d=m*q#\n",
      "D=Z2*m#\n",
      "b=3*d/4#\n",
      "V=2*pi*n*D/(2*60*1000)#\n",
      "Cv=6/(6+V)#\n",
      "y=0.154-(0.912/Z2)#\n",
      "Y=pi*y#\n",
      "Sb=sigb*b*Cv*m*Y#\n",
      "K=0.415#\n",
      "Sw=b*D*K#\n",
      "print \"Sb is %0.0f N  \"%(Sb)#\n",
      "print \"\\nSw is %0.0f N  \"%(Sw)#\n",
      "\n",
      "#The difference in the value of Sb is due to rounding-off the values."
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Sb is 8286 N  \n",
        "\n",
        "Sw is 3362 N  \n"
       ]
      }
     ],
     "prompt_number": 13
    }
   ],
   "metadata": {}
  }
 ]
}