SYMBOLS

r _c = distance from center to cam, in

y = follower displacement, in

= follower acceleration, in/sec ²

_m = maximum follower acceleration, in/sec ²

_? = follower deviation from theoretical cam curve, in

F = normal force, lb

I = moment of inertia of roller, lb-in-sec ²

R _c = radius of cutter or grinder, in

R _r = roller radius, in

? = angular acceleration of roller, rad/sec ²

= static coefficient of friction between cam and roller

? = error or deviation from theoretical cam profile, in

? = increment angle, rad

? = cam speed, rad/sec

10.1 MANUFACTURING METHODS

It is important that engineers be aware of the fabrication techniques involved in manufacturing and inspecting the actual cam produced from the design information. They should be knowledgeable about the experience and level of dedication of the machine shop workers in making and assembling the parts. To ensure quality (1) errors in fabrication and misalignment in assembly should be eliminated; (2) cam fabrication should be usefully monitored, and (3) tool wear, vibrations, and chatter should be eliminated. Necessary periodic inspection also should be minimized.

Let us consider the overall machine tool system next. The kinds and ages of the machine tools are important factors. New equipment always functions with greater precision than old equipment. Also, in cutting cams, the cams surface and...