Cogged belts have grooves, or notches, on the inner surface of the belt that run perpendicular to the length of the belt. Also called synchronous belts, the cogs allow the belt to bend and flex more easily, dissipating heat and running cooler than non-cogged belts and last longer. They are ideal for use in small-diameter pulleys, drives with twists or turns, or with sprocket pulleys to limit slip. They are not intended for use in clutching applications. Cogged belts may be a better choice when vibration damping is needed, or shock loads cause abrupt torque changes that could shear a synchronous belt's teeth.
Shown to right is a Stens Cogged Belt