Camshaft Engineering Company

These programs require specific design data relating to the valve train geometry for the engine concerned, to be provided by the client. Alternately these can be measured by CEC from components supplied. This data includes full spring specifications, component weights, and rocker inertia data. This is particularly critical for the pivoted follower design, as the cam profile is unique to the pivot geometry for which it is designed. It is not possible to use a profile from another engine design of differing geometry and achieve satisfactory results.

The present sequence of design is to first establish the valve lift profile required including opening and closing ramps. Acceleration and velocity maxima are determined and checked against limits possibly imposed by contact stress, available spring force, follower diameter or pivot rocker pad length, etc. The lobe profile is then computed, with further checks for negative flank radius (concave) relative to grinding wheel diameter. A master lobe is precision NC machined and verified by Cam Doctor (in conjunction with a cylinder head in the case of overhead camshaft pivoted designs). Cam lobe to follower contact is also confirmed at this stage. If all tests are clear, the master lobe is used to produce a cam machine master for the grinding of the camshaft. Final Cam Doctor verification "in head" or on the stand completes the process.

Further development of computer design and manufacturing methods now allow the grinding machine master disc to be NC profile machined directly from computer data, eliminating the master lobe stage. This results in higher precision of the machine master, and consequentially, the finished camshaft lobes.