Criterii:
*structura: plana (a...g), spatiala (h)
*miscarea camei: rotatie (a, b, d, e, g, h)
*miscarea tachetului: translatie (a, c, e - centric, b, g - excentric), oscilanta (d)
*contact cama-tachet: prin forta (a, b, c, d, f), prin forma (e, h, g)
*forma tachetului: varf (a), rola (c, d, f, g, h), plan (b, e)