Toothed belt transmissions are widely used in modern engineering, from inkjet printer
transmissions through motorbike primary and secondary transmissions to airplane luggage
elevator transmissions. They are silent, do not need excessive maintenance, and allow
cost reduction. Similarly, internal combustion engine timing drive transmissions are
often realized by timing belt.
In engine timing drive transmissions, driving and driven pulleys generally do not
allow adjusting belt tension. Thus, a belt tensioner is used to furnish and maintain
preload force. It also compensates belt length variation under load. The tensioner
consists of a short arm fixed by pivot on the engine block on one end and has an idler
pulley on the other end. A torsional stiffness and a torsional damping element also
join the arm and the engine block.
Numerical model and simulation software were developed to modelize the timing drive
transmission. For a given belt transmission layout, various stiffness values were
tested numerically. Simulation input data come from measurements on real engines.
Viscous and Coulomb-type damping cases were tested. System response to various parameter
values is studied and discussed.