Difference between revisions of "Contact Spring Calculations"

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(→‎6.4.7 Contact Spring Calculations)
(→‎6.4.7 Contact Spring Calculations)
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:<math>\times= \frac{12 \cdot F}{(2 + B_{min} /B_{max})}\times \frac{L^3}{E \times B \times D^3}</math>
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:<math>\times= \frac{12 \cdot F}{(2 + B_{min} /B_{max})}\cdot \frac{L^3}{E \cdot B \cdot D^3}</math>
  
  

Revision as of 14:48, 30 April 2014

6.4.7 Contact Spring Calculations

One side fixed contact bending spring

The influence of the dimensions can be illustrated best by using the single side fixed beam model Figure 1 (Fig. 6.20). For small deflections the following equation is valid:

F = \frac{3 \cdot E \cdot J}{L^3}

where J is the momentum of inertia of the rectangular cross section of the beam

J = \frac{B \cdot D^3}{12}

For springs with a circular cross-sectional area the momentum of inertia is

J=\pi D^4/64
D= Durchmesser

To avoid plastic deformation of the spring the max bending force σmax cannot be exceeded

\sigma_{max} = \frac{3 \cdot E \cdot D}{2L^2}\cdot_{max}

The stress limit is defined through the fatigue limit and the 0.2% elongation limit resp.

\times_{max} = \frac{2 \cdot L^2}{3 \cdot D \cdot E}R_{p0,2}


and/or

F_{max} = \frac{B \cdot D^2}{6L}R_{p0,2}


  • Special Spring Shapes
    • Triangular spring

      • Deflection

      \times = \frac{F}{2 \cdot E \cdot J}L^3


      = \frac{6 \cdot F}{E \cdot B}\cdot \frac{L^3}{D^3}


      Max. bending force

      \sigma_{max}= \frac{18 \cdot F \cdot L}{B \cdot D^2}
    • Trapezoidal spring

      • Deflection

      \times = \frac{F}{(2 + B_{min} /B_{max})}\times \frac{L^3}{E \cdot J}


      \times= \frac{12 \cdot F}{(2 + B_{min} /B_{max})}\cdot \frac{L^3}{E \cdot B \cdot D^3}


      Max. bending force

      \sigma_{max}= \frac{18 \cdot F \cdot L}{(2 + B_{min} /B_{max}) \cdot B_{max} \cdot D^2 }

    References

    References

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