Involute Spur Gear Template Development by Parametric Technique Using Computer Aided Design (Pp. 415-429)

There are many methods available for developing profiles of gear and spline teeth. Most of the techniques are inaccurate because they use only an approximation of the involute curve profile. The parametric method developed in this paper provides accurate involute curve creation using formulas and exact geometric equations. In addition, the involute curve by equation technique allows using either Cartesian in terms of X, Y, and Z or cylindrical coordinate systems to create the involute curve profile. Since spur gear geometry is controlled by a few basic parameters, a generic gear can be designed by three common parameters namely the pressure angle (a), the module (m), and the number of teeth (z). Most of the present day CAD systems have no built-in tool for designing such gears. This paper is an attempt in utilizing the concept of parametric technology to develop a template gear. The gear so developed has true involute profile, which is a realistic design. This will allow making changes to the gear design by using