{ "cells": [ { "cell_type": "markdown", "metadata": {}, "source": [ "# Chapter 22: FRICTION CLUTCHES" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## Example 22.10: FC2210.sce" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": true }, "outputs": [], "source": [ "// 22-10\n", "clc;\n", "clear;\n", "w2=2*%pi*1400/60;\n", "w1=0.8*w2;\n", "P=40*10^3;\n", "T=P/w2;\n", "n=4;\n", "T1=T/4;\n", "R=0.16;//Inner radius of drum\n", "r=0.13;//radial distance of each shoe from axis of rotation\n", "u=0.22;//coefficient of friction\n", "x=u*r*R*((w2^2)-(w1^2))\n", "m =T1/x;\n", "l=R*%pi/3;\n", "N=T1/(R*u);\n", "p=1*10^5;\n", "b=N/(p*l)*10^3;\n", "\n", " // printing data in scilab o/p window\n", "printf('\nThe full speed is %0.1f rad/sec',w2);\n", "printf('\nThe engagement speed is %0.2f rad/sec',w1);\n", "printf('\nThe number of shoes is %0.0f ',n);\n", "printf('\nThe Torque is %0.1f Nm',T);\n", "printf('\nThe Torque per shoe is %0.1f Nm',T1);\n", "printf('\nThe mass per shoe is %0.2f kg',m);\n", "printf('\nThe length of friction lining is %0.5f m',l);\n", "printf('\nThe width is %0.1f mm',b);" ] } , { "cell_type": "markdown", "metadata": {}, "source": [ "## Example 22.1: FC221.sce" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": true }, "outputs": [], "source": [ "// 22-1\n", "clc;\n", "clear;\n", "u=0.28 //(coefficient of friction)\n", "N=300 //(Engine rpm)\n", "I=7.2 \n", "Pmax= 0.1; \n", "R1=70;\n", "R2=110;\n", "n=2; //(Both sides of the plate are effective)\n", "//Using Uniform Wear Theory\n", "//Axial Force W\n", "W=n*%pi*Pmax*R1*(R2-R1);\n", "//Frictional Torque Tf\n", "Tf=u*W*(R1+R2)/2*(10^-3);\n", "w=2*%pi*N/60;\n", "//Power P\n", "P=Tf*w;\n", "//Torque = Mass moment of inertia*angular acceleration\n", "a=Tf/I;\n", "t=w/a; \n", "//Angle turned by driving shaft theta1 through which slipping takes place\n", "theta1=w*t;\n", "//angle turned by driven shaft theta2\n", "theta2=a*(t^2)/2;\n", "E=Tf*(theta1-theta2);\n", "\n", " // printing data in scilab o/p window\n", "printf('\nThe force is %0.1f N',W);\n", "printf('\nThe Torque is %0.2f Nm',Tf);\n", "printf('\nThe Power is %0.0f W',P);\n", "printf('\nThe angular acceleration is %0.2f rad/sec^2',a);\n", "printf('\nThe time taken is %0.1f sec',t);\n", "printf('\nThe energy is %0.2f Nm',E);\n", "\n", "//The difference in the answer of energy 'E' is due to rounding-off of values.\n", "\n", "\n", "\n", "\n", "\n", "" ] } , { "cell_type": "markdown", "metadata": {}, "source": [ "## Example 22.2: FC222.sce" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": true }, "outputs": [], "source": [ "// 22-2\n", "clc;\n", "clear;\n", "//Power P\n", "P=80*10^3; //(Watt)\n", "N=3000; //(Engine rpm)\n", "w=2*%pi*3*10^3/60\n", "Tf=8*10^4/w;\n", "Rm=100;//(mm)\n", "p=0.2 //N/mm^2\n", "u=0.22 \n", "// let width b= (R1-R2). \n", "//Axial force W=2*pi*Rm*b*p\n", "//Torque T=u*W*Rm\n", "b=Tf/(u*2*%pi*(Rm^2)*p);\n", "b=50; \n", "R2=Rm+b;\n", "R1=Rm-b;\n", "Di=2*R1; //inner diameter\n", "W=2*%pi*Rm*b*p;\n", "n=8; //n is number of springs\n", "//Axial force per spring W1\n", "W1=W/n;\n", "W1=W1+15;\n", "//axial deflection del\n", "del=10; \n", "//stiffness k\n", "k=W1/del;\n", "// Spring index C\n", "C=6;\n", "//number of coils n1\n", "n1=6; //Assumption\n", "d=k*n*n1*(C^3)/(80*10^3);\n", "d=11; // Rounding off to nearest standard value\n", "D=C*d;\n", "clearance=2;\n", "FL=((n1+2)*d)+(2*del)+clearance; // two end coils, therefore (2*del)\n", "\n", " // printing data in scilab o/p window\n", "\n", "printf('\nThe Torque is %0.2f Nm',Tf);\n", "printf('\nThe width is %0.0f mm',b);\n", "printf('\nThe force is %0.0f N',W);\n", "printf('\nThe Axial force per spring is %0.0f N',W1);\n", "printf('\nThe Spring stiffness is %0.0f N/mm',k);\n", "printf('\nThe Spring wire diameter is %0.0f mm',d);\n", "printf('\nThe Mean coil diameter is %0.0f mm',D);\n", "printf('\nThe Free length is %0.0f mm',FL);\n", "" ] } , { "cell_type": "markdown", "metadata": {}, "source": [ "## Example 22.3: FC223.sce" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": true }, "outputs": [], "source": [ "// 22-3\n", "clc;\n", "clear;\n", "//Power P\n", "P=40*10^3 //Watt\n", "n1=100; //rpm\n", "n2=400; //rpm\n", "//Speed factor Ks\n", "Ks=0.9+0.001*n2;\n", "//Clutch power Pc\n", "Pc=P*n2/(n1*Ks)*10^-3;\n", "\n", " // printing data in scilab o/p window\n", "printf('\nThe Speed factor is %0.1f ',Ks);\n", "printf('\nThe clutch poweris %0.0f KW',Pc);" ] } , { "cell_type": "markdown", "metadata": {}, "source": [ "## Example 22.4: FC224.sce" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": true }, "outputs": [], "source": [ "//22-4\n", "clc;\n", "clear;\n", "// plot Torque vs Ro/Ri\n", "//x=Ro/Ri\n", "//According to Uniform Wear theory\n", "x=[0 0.2 0.4 0.577 0.6 0.8 1.0];\n", "n=length(x);\n", "for i=1:n\n", " Tf(i)=(x(i)-(x(i)^3));\n", "end\n", "plot (x,Tf);\n", "xtitle('','Ro/Ri');\n", "ylabel('Tf');\n", "xgrid(2);" ] } , { "cell_type": "markdown", "metadata": {}, "source": [ "## Example 22.5: FC225.sce" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": true }, "outputs": [], "source": [ "// 22-5\n", "clc;\n", "clear;\n", "n1=4;\n", "n2=3;\n", "n=(n1+n2-1);\n", "R2=80;\n", "R1=50;\n", "//According to Uniform Pressure Theory\n", "//W=p*pi*((R2^2)-(R1^2)) T=n*2*u*W*((R2^3)-(R1^3))/(((R2^2)-(R1^2))*3)\n", "P=15*10^3;\n", "N=1400;\n", "u=0.25;\n", "w=2*%pi*N/60;\n", "T=P/w;\n", "W=T*3*((R2^2)-(R1^2))/(n*2*u*((R2^3)-(R1^3)))*10^3;\n", "p=W/(%pi*((R2^2)-(R1^2)));\n", "\n", " // printing data in scilab o/p window\n", "printf('\nThe angular speed is %0.2f rad/sec',w);\n", "printf('\nThe Torque is %0.3f Nm',T);\n", "printf('\nThe uniform pressure is %0.3f N/mm^2',p);\n", "printf('\nThe Force is %0.1f N',W);\n", "\n", "\n", "\n", "" ] } , { "cell_type": "markdown", "metadata": {}, "source": [ "## Example 22.6: FC226.sce" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": true }, "outputs": [], "source": [ "//FRICTION CLUTCHES\n", "// PAGE 584, 22-6\n", "clc;\n", "P=5*10^3;\n", "N=1000;\n", "w=2*%pi*N/60;\n", "Rm=50;\n", "pm=0.3;\n", "Tf=P/w;\n", "u=0.1;\n", "R2=50*2/(0.6+1);\n", "R1=0.6*R2;\n", "//According to uniform Wear theory\n", "W=pm*Rm*(R2-R1)*2*%pi;\n", "n=Tf*(10^3)/(u*W*Rm);\n", "pmax=pm*Rm/R1;\n", "\n", " // printing data in scilab o/p window\n", "printf('\nThe angular speed is %0.2f rad/sec',w);\n", "printf('\nThe Torque is %0.3f Nm',Tf);\n", "printf('\nThe Inner radius is %0.1f mm',R1);\n", "printf('\nThe Outer radius is %0.1f mm',R2);\n", "printf('\nThe number of contacting surfaces is %0.0f ',n);\n", "printf('\nThe max. pressure is %0.1f N/mm^2',pmax);" ] } , { "cell_type": "markdown", "metadata": {}, "source": [ "## Example 22.7: FC227.sce" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": true }, "outputs": [], "source": [ "// 22-7\n", "clc;\n", "clear;\n", "P=12*10^3;\n", "N=750 //Speed=N\n", "w=2*%pi*N/60;\n", "Tf=P/w;\n", "p1=0.12;\n", "a=12.5;//Semi-cone angle\n", "u=0.3;\n", "k=u*0.18246*1.121/0.21644;\n", "R1=(Tf*(10^3)/k)^(1/3);\n", "R2=R1*1.242;\n", "Rm=1.121*R1;\n", "W=2*%pi*p1*R1*(R2-R1);\n", "\n", " // printing data in scilab o/p window\n", "printf('\nThe angular speed is %0.2f rad/sec',w);\n", "printf('\nThe Torque is %0.1f Nm',Tf);\n", "printf('\nThe Inner radius is %0.1f mm',R1);\n", "printf('\nThe Outer radius is %0.1f mm',R2);\n", "printf('\nThe mean radius is %0.2f mm',Rm);\n", "printf('\nThe axial force is %0.0f N',W);\n", "\n", "//The difference in the answer is due to rounding-off of values." ] } , { "cell_type": "markdown", "metadata": {}, "source": [ "## Example 22.8: FC228.sce" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": true }, "outputs": [], "source": [ "//22-8\n", "clc;\n", "clear;\n", "//semi-cone angle is given as 15 degree\n", "k=sin(15*%pi/180);\n", "u=0.3;\n", "W=300;\n", "Rm=90/2;\n", "Tf=u*W*Rm/k;\n", "Tf=Tf*(10^-3);\n", "I=0.4;\n", "a=Tf/I;\n", "N=1440;\n", "w=2*%pi*N/60;\n", "t=w/a;\n", "//During Slipping\n", "theta1=w*t;\n", "theta2=theta1/2;\n", "U=Tf*(theta1-theta2);\n", "\n", " // printing data in scilab o/p window\n", "printf('\nThe Torque is %0.3f Nm',Tf);\n", "printf('\nThe angular acceleration is %0.3f rad/sec^2',a);\n", "printf('\nThe angular speed is %0.1f rad/sec',w);\n", "printf('\nThe time taken is %0.2f sec',t);\n", "printf('\nThe Energy lost in friction is %0.0f Nm',U);" ] } , { "cell_type": "markdown", "metadata": {}, "source": [ "## Example 22.9: FC229.sce" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": true }, "outputs": [], "source": [ "// 22-9\n", "clc;\n", "clear;\n", "P=15*10^3;\n", "Ka=1.25;\n", "N=1500;\n", "w=2*%pi*N/60;\n", "Tf=P/w;\n", "d=(Tf*16/(50*%pi))^(1/3);\n", "d=25;\n", "Rm=5*d;\n", "Pav=0.12;\n", "u=0.22;\n", "b=Tf/(%pi*u*Pav*(Rm^2));\n", "b=40;\n", "R1=Rm-(b*sin(15*%pi/180)/2);\n", "R2=Rm+(b*sin(15*%pi/180)/2);\n", "\n", " // printing data in scilab o/p window\n", "printf('\nThe Torque is %0.2f Nm',Tf);\n", "printf('\nThe shaft diameter is %0.0f mm',d);\n", "printf('\nThe width is %0.0f mm',b);\n", "printf('\nThe Inner radius is %0.1f mm',R1);\n", "printf('\nThe Outer radius is %0.1f mm',R2);" ] } ], "metadata": { "kernelspec": { "display_name": "Scilab", "language": "scilab", "name": "scilab" }, "language_info": { "file_extension": ".sce", "help_links": [ { "text": "MetaKernel Magics", "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md" } ], "mimetype": "text/x-octave", "name": "scilab", "version": "0.7.1" } }, "nbformat": 4, "nbformat_minor": 0 }