Computer model of the spur involute gear mesh dynamics in gearboxes

A dynamical model of the gearbox with spur involute mesh is under construction. The main attention is paid to the design technology of the cylindrical bodies elastic contact models. First of all, an algorithm for tracking of contact for cylindrical surfaces directed by involutes underwent upgrading. This algorithm is reduced «simply» to tracking of two involutes. As a result it turned out that common line normal to both curves, involutes, of contacting coincides always with line of action. This causes immediately a simplified technique for contact tracking without use of differential or algebraic equations. This technique is reduced to simple formulae for direct computations. At the same time dynamical models of the bodies involved, gearwheels and gearbox housing, continue to be three-dimensional.

Contact model provides a full possibility to take into account unilateral nature of teeth interacting while meshing. The backlash may arise dynamically for any side of teeth pairs at contact. In particular, the model simulates dynamics for arbitrary regimes of the pinion rotation acceleration/deceleration.

The mesh construct is such that for any side (for both the forward and backward contacting) of teeth at contact the mesh ratio is greater than one. The mesh multiplicity for real gears prevents potential jamming for gearwheels while the teeth pairs switching process. Thus our implementation assumes mesh cycles overlapping: new contact arises beforehand the old one will vanish.