Design of disc cams and their followers: examples.
Abstract:ESDU 85013 is one of a group dealing with the design of cam and follower systems. By means of two fully-worked practical design studies it shows how the procedures are used in practice. Both examples relate to lightly-loaded moderate-speed applications. The first is a feeder mechanism of a general packaging machine and the design requirement is to meet specified intermediate displacements and velocities to synchronise with associated parts of the machine. The design adopted is a disc cam with translating roller follower using compression springs to maintain follower contact. Profile blending is used, the detailed design of the springs is considered, and the contact stresses and lubricant film thickness are checked to ensure a satisfactory design. The second example uses a cognate cam with swinging roller follower to operate the pusher of a conveyor take-off mechanism. In this case the design is dominated by the stiffness of the system. The period ratio is calculated from the evaluation of the stiffness and an appropriate cam law is chosen. Subsequent calculations determine the basic dimensions, profile shape, follower bearing load capacity, and the selection of a suitable cam material from a knowledge of the contact stresses.
|Data Item ESDU 85013|