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{
"cells": [
{
"cell_type": "markdown",
"metadata": {},
"source": [
"# Chapter 8: Spring Design"
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"## Example 8.1: Design_of_Helical_Compression_Spring.sce"
]
},
{
"cell_type": "code",
"execution_count": null,
"metadata": {
"collapsed": true
},
"outputs": [],
"source": [
"clc;\n",
"clear;\n",
"mprintf('MACHINE DESIGN \n Timothy H. Wentzell, P.E. \n EXAMPLE-8.1 Page No.160\n');\n",
"Dm=0.625; //[in] Mean diameter of spring\n",
"F=35; //[lb] Load\n",
"K=1.25; //[] Wahl factor for Dm/Dw=6.25 (figure 8.8)\n",
"Q=190000; //[lb/in^2] Expected ultimate strength \n",
"LF=0.263; //[] Loading factor\n",
"Dw=(K*8*F*Dm/(LF*%pi*Q))^(1/2.846); //[in] Wire diameter\n",
"mprintf('\n The wire diameter of spring is %f in.',Dw);\n",
"//Use U.S Steel 12-gage wire: Dw=0.105 in."
]
}
,
{
"cell_type": "markdown",
"metadata": {},
"source": [
"## Example 8.2: Determination_of_number_of_coils.sce"
]
},
{
"cell_type": "code",
"execution_count": null,
"metadata": {
"collapsed": true
},
"outputs": [],
"source": [
"clc;\n",
"clear;\n",
"mprintf('MACHINE DESIGN \n Timothy H. Wentzell, P.E. \n EXAMPLE-8.2 Page No.163\n');\n",
"Dw=0.105; //[in] Wire diameter\n",
"Dm=0.620; //[in] Mean diameter of spring\n",
"F=35; //[lb] Load\n",
"G=11.85*10^6; //[lb/in^2] Shear modulus of elasticity\n",
"Delta=0.5; //[in] Deflection\n",
"Na=Delta*G*Dw^4/(8*F*Dm^3); //[] Number of active coils\n",
"Nat=Na+2; //[] Total number of coils\n",
"Lf=2; //[in] Free length of spring\n",
"P=(Lf-2*Dw)/Nat; //[in] Pitch (Table 8.1)\n",
"mprintf('\n Pitch is %f in.',P);\n",
"k=G*Dw^4/(8*Dm^3*Na); //[lb/in] Spring rate\n",
"mprintf('\n Spring rate is %f lb/in.',k);\n",
"mprintf('\n The total number of coils necessary to meet design criteria are %f.',Nat);\n",
"//Note: The deviation of answer from the answer given in the book is due to round off error.(In the book values are rounded while in scilab actual values are taken)\n",
"//Note: The deviation of answer from the answer given in the book is due to round off error.(In the book values are rounded while in scilab actual values are taken)"
]
}
,
{
"cell_type": "markdown",
"metadata": {},
"source": [
"## Example 8.3: Stability_of_Spring.sce"
]
},
{
"cell_type": "code",
"execution_count": null,
"metadata": {
"collapsed": true
},
"outputs": [],
"source": [
"clc;\n",
"clear;\n",
"mprintf('MACHINE DESIGN \n Timothy H. Wentzell, P.E. \n EXAMPLE-8.3 Page No.165\n');\n",
"Lf=2; //[in] Free length of spring\n",
"Dm=0.620; //[in] Mean diameter of spring\n",
"R=Lf/Dm; //[] Free lengtth to mean diameter ratio\n",
"mprintf('\n The ratio of the free length of spring to mean diameter of spring is %f.',R);\n",
"mprintf(' From Figure 8.9 for squared and ground ends, this is a stable spring.');"
]
}
,
{
"cell_type": "markdown",
"metadata": {},
"source": [
"## Example 8.4: Deflection_of_Spring.sce"
]
},
{
"cell_type": "code",
"execution_count": null,
"metadata": {
"collapsed": true
},
"outputs": [],
"source": [
"clc;\n",
"clear;\n",
"mprintf('MACHINE DESIGN \n Timothy H. Wentzell, P.E. \n EXAMPLE-8.4 Page No.165\n');\n",
"F=35; //[lb] Load\n",
"k=73.3; //[lb/in] Spring rate\n",
"x=F/k; //[in] Deflection \n",
"mprintf('\n The deflection in the spring would be %f in.',x);"
]
}
,
{
"cell_type": "markdown",
"metadata": {},
"source": [
"## Example 8.5: Flat_Springs.sce"
]
},
{
"cell_type": "code",
"execution_count": null,
"metadata": {
"collapsed": true
},
"outputs": [],
"source": [
"clc;\n",
"clear;\n",
"mprintf('MACHINE DESIGN \n Timothy H. Wentzell, P.E. \n EXAMPLE-8.5 Page No.166\n');\n",
"b=12; //[in] Width of plate\n",
"h=1; //[in] Thickness of plate\n",
"L=72; //[in] Length of plate\n",
"I=b*h^3/12; //[in^4] Moment of inertia\n",
"Delta=4; //[in] Deflection\n",
"E=10*10^6; //[lb/in^2] Modulus of elasticity\n",
"F=3*Delta*E*I/L^3; //[lb] Force\n",
"mprintf('\n The force at this point is %f lb.',F);\n",
"k=F/Delta; //[lb/in] Stiffness\n",
"mprintf('\n stiffness is %f lb/in.',k);\n",
"//Note: The deviation of answer from the answer given in the book is due to round off error.(In the book values are rounded while in scilab actual values are taken)\n",
"//Note: The deviation of answer from the answer given in the book is due to round off error.(In the book values are rounded while in scilab actual values are taken)"
]
}
,
{
"cell_type": "markdown",
"metadata": {},
"source": [
"## Example 8.6: Energy_from_Deflection.sce"
]
},
{
"cell_type": "code",
"execution_count": null,
"metadata": {
"collapsed": true
},
"outputs": [],
"source": [
"clc;\n",
"clear;\n",
"mprintf('MACHINE DESIGN \n Timothy H. Wentzell, P.E. \n EXAMPLE-8.6 Page No.167\n');\n",
"F=322; //[lb] Force\n",
"Delta=4; //[in] Deflection\n",
"U=F*Delta/2; //[in*lb] Energy\n",
"mprintf('\n The energy from the 4-inch deflection was %f lb*in.',U);"
]
}
],
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"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"
}
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"mimetype": "text/x-octave",
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"version": "0.7.1"
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|
