Motor engineering utilizes V-belts in automobiles as transmission belts. A V-belt operates, among other things, the ventilator, the water pump for the cooling system, the hydraulic pump and the alternator. With the term V-belt it is meant a flexible, self-contained loop that serves for the transmission of the motion power that is produced between two shafts; it possesses a wedge-like shape, that is to say, a trapezoidal cross-section. Such shape consents a considerably more efficient friction, which, in turn, allows optimum power transmission. V-belts are manufactured as endless strips that are trimmed to the required length only in the fitting stage. The belt ends are subsequently welded together.
In practice, we can distinguish between four types of V-belts which are employed in different application fields: classic V-belts, which are known because of their high reliability, narrow V-belts which make for improved power transmission, raw edged V-belts, whose advantage lies in both their reduced wear and tear and their running precision, and, finally, moulded notched V- belts, that due to their prolonged duration and lower energy consumption, are fitted preferentially to new motor units.
- Classic V-belts
- Narrow V-belts
- Raw edged V-belts
- Moulded notched V-belts
A further development is constituted by the V-ribbed belt, which runs on specially shaped wheels. It is a hybrid type of belt that reunites all the best features of both a V-belt and a flat belt in one. In contrast to flat belts, a V-belt is standardised and may be swapped regardless of manufacturing make. The V-belts that are fitted in cars are predominantly made of rubber. Into this material are embedded textile fibres and metal fibres – in the latter’s case, mainly made of steel. After a certain period of use, V-belts tend to inevitably get slack through stretching, and eventually require changing. It may happen that a V-belt starts to make a “squeaking” noise, although that does not necessarily mean that it needs to be swapped for a new one. Especially in the Winter season, in much colder temperatures, transmission belts tend to “squeak” more frequently, because the cold causes the belt to become harder and less flexible, effectively impairing its traction. If the “squeaking” persists and becomes constant, it means, though, that the V-belt must be swapped, because it has lost its optimum tension, and no longer functions faultlessly.