1.1 INTRODUCTION

A cam is an element of the cam-follower mechanical system that compels the movement of the follower by direct contact. The motion of the follower is the result of a program. Just as a computer is programmed, so is a cam. Thus, the system can be thought of as a mechanical information device. Accordingly, the goal of the designers is to build a program, establish the locus of the contact points between the cam and follower, produce the cam profile coordinates system, and fabricate the cam within an acceptable accuracy. After all the parts are assembled the performance of the cam-follower system is observed.

No one is sure where and how cams got their start. The Sanskrit (Indo-Iranian) term Jambha ( cog, peg, or tooth ) may indicate the geographic area in which they had their beginnings, and so may the Teutonic Kambr (toothed instrument), which refers to cam mechanisms that have their origin in the wedge (a linear cam) and have been found in Paleolithic Age relics of about 10,000 years ago. The later construction of the great pyramids of Egypt also involved the use of the wedge. However, it was the genius of Leonardo da Vinci that produced a modern design cam applied to a machine for pumping water.

Cam-follower mechanisms are found in almost all mechanical devices and machines (i.e., agriculture, transportation equipment, textiles, packaging, machine tools, printing presses, automobile internal combustion engines, food processing machines, switches, ejection molds, and control...