Modeling of a spur gear in SolidWorks

Here, a model of the spur gear in SolidWorks is developed. By changing the configurations, the design of desired spur gear can be obtained using this model.

For example, we design a spur gear for the following configuration:

$*\ Diametral\ pitch, P = 2$

$*\ Number\ of\ teeth, N = 20$

$*\ Pressure\ angle, \phi = 20\textdegree$

$*\ Face width = 2 inches$

Using the equations of spur gear, we can find the remaining properties of the spur gear:

$*\ Pitch\ diameter, d_p = \frac{N}{P}$

$*\ Base\ circle\ diamter, d_b = d_p cos\phi$

$*\ Addendum, a = \frac {1} {P}$

$*\ Dedendum, b = \frac {1.25} {P}$

$*\ Addendum\ circle\ diamter, D_a = d_p + 2a$

$*\ Dedendum\ circle\ diamter, D_d = d_p - 2b$

$*\ Clearance, c = b - a$

$*\ Base circle radius, r = \frac{d_b} {2}$

$*\ \alpha = \frac {\sqrt {d_p^2 - d_b^2}} {d_b} - \phi$

$*\ \beta = \frac {360} {4N} - \alpha$

Step 1: We will use the above variables to model the spur gear. So, add them inside the global variables in SolidWorks. Go to Tools > Equations. Here, under the global variables, add all the variables.