Abstract:

ESDU 95001 and the associated computer program presents methods for the calculation of the pressure angle, the radius of curvature of the cam profile, the radius of curvature of the pitch curve and the coordinates of the cam profile, throughout one complete cycle of the cam at user-specified intervals of cam rotation. The calculated quantities are provided for a specified follower motion and with any one of the commonly-used follower types, i.e. translating or swinging, flat-faced, domed or roller followers. The methods are equally applicable to cam systems with spring force closure or body force closure, for example, cognate cams or grooved cams. The methods and program checks that interference (undercutting) between the cam and the follower or between the cam and the cutter is avoided. In addition, when the profile has been finalised and the cam is to be manufactured, a series of cutter coordinates for direct transfer to a computer-controlled machine is provided.

The follower motion is specified in terms of a cam law which provides a relationship between the motion of the cam and the motion of the follower. Six commonly-used cam laws covering both trignometrical and polynomial types are included in the computer program. The motion of the follower, in the form of values of displacement, velocity, acceleration and jerk can also be directly input to the program at run time via a motion data file.

Six examples illustrating the operation and use of the program are included.