SPRINGS 



145 



CANTILEVER SPRINGS— I 

 Maximum Fiber Stress, Length, Deflection, and Thickness 



E= elastic modulus 

 = I5,50QOOO max, for brass 

 = 16,500,000 max. for phos. bronze 



S= max. fiber stress 

 5EDii 



Example 

 Bronze spring stressed to 31,000 lb. 

 per sq.in.,ora brass spring stressed 

 to 30^000 lb. per sq. in., and O.OISSin. 

 thick, and 2 in. long will deflect 0.34 in 



Values of h and S cut by one 

 edge (A C) of right angled 

 triangle, with values of Dand 

 L cut D/ other edge (AS} 

 satisfy equation for maximum 

 fiber stress 



5EDh 

 S= 21^ 



lllllllllllllllllll I lllllllllrhin lllllllllllllllllll lllllllllllllll lllllllllll I 



^^ Deflection I'd} in Inches 



/ 

 / 



y Spring Length (L) in Inches 

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CD o o 



— i O dO 



