When axial movement between the sha

When axial movement between the shaft and hub is required, relative rotation is prevented by means of splines machined on the shaft and into the hub(see Fig.4.6).There are two forms of splines: straight-sided splines and involute splines. The former is relatively simple and employed in some machine tools. The latter has an involute curve in its outline, which is in widespread use on gears. The involute form is preferred because it provides for self-centering of the mating element and because it can be machined with standard hobs used to cut gear teeth.