ABSTRACT
Static determination of T.E. under load is sufficient for most drives where the loading is relatively heavy and the inertias are low so that there is little danger of the length of line of contact varying greatly or of the teeth losing contact. The T.E. is then the input vibration and, as the system remains reasonably linear in its behaviour, it can be modelled using a conventional matrix approach in the frequency domain. Drives which are lightly loaded or which drive high inertias, such as printing rolls, may lose contact with rather dramatic results. It is then possible for the teeth to be in contact for less than 10% of the time with rather large impulsive forces while they are in contact. The simple assumption of a linear system with an input displacement of the quasi-static T.E. is then no longer realistic and a more detailed model is required (see section 5.2 and Chapter 11).
