"Dongfeng Xiaokang V29" minibus fan belt often loose and squeaking sound how? Please expert help answer, thank you!

Fan belt ringing, is a car engine fan belt (belt) in some cases and belt groove slipping each other and produce an abnormal sound, is a kind of driver upset noise. This phenomenon is more common in low-displacement gasoline engines that use "O" type V-belts as fan belts. Although in some models of the engine belt does not drive the fan, but only drive the water pump, generator, air compressor and other accessories running, but customary still call it a fan belt, the belt produced by the abnormal noise collectively referred to as the fan belt ring. In order to overcome this noise, many models of small cars fan belt using the inner circumference of the toothed high efficiency anti-slip belt, but the effect is not good.

1. The prevalence of rattling

Walking the streets, as long as you pay attention, from time to time, you can hear different models of cars in the vehicle at the beginning of the start or low-speed forward (low-speed shifting) issued a sharp "squeak" strange sound. In the maintenance of various models of small cars, in the trial, but also often hear different degrees of fan belt. One of the fan belt, air compressor belt or generator belt in the idle speed of the slight "squeaky" sound; in the process of acceleration or high-speed conditions issued by a sharp "squeak" sound; there are in the vehicle at the beginning of the start or low-speed shift issued by the sharp "Squeak" sound. This is in many cars such as Santana, Jetta, Fukang, Peugeot, Changan, Otto, Xiali, etc., as well as many mini-vans such as Changhe, Changan, Songhuajiang, etc. is very common, wherever the use of an ordinary triangle belt for the fan belt, have appeared in the fan belt ringing, other light, medium-sized buses and trucks, there are also occasional phenomena occurring in the fan belt ringing, but the relative incidence of a relatively low.

2. Eliminate the traditional method of rattling and the effect

Drivers hate the fan belt rattling, the general situation of drivers and mechanics to deal with the fan belt rattling methods are as follows.

1) a new fan belt: can eliminate the sound of time for half a day to 30 days, the length of time and the smoothness of the belt grooves inversely proportional to the degree of the pulley, that is, the pulley belt grooves ground the smoother, in addition to the sound of the time is shorter, and soon appeared on the original zhouzou.

2)Change the new generator pulley: can eliminate the sound of time for 10-45 days, the length of time is also inversely proportional to the smoothness of its pulley groove, even if it is at the same time to replace the new fan belt, is also the same.

3) strongly increase the fan belt tension: the time to eliminate the noise for l hours to 10 days. Elimination of rattling time and pulley groove smoothness and belt on both sides of the smoothness of the working surface is inversely proportional.

4) in the fan belt on both sides of the working surface coated with a small amount of oil. The time to eliminate the noise is 5-15 days. Apply a little more oil to eliminate the rattling time is relatively longer.

From the above method can be seen, although in the treatment of the time generally can be achieved at the time of rattling no longer produces, but the overall view of the maintenance time is very short, especially in the pulley groove are ground smoother, the morning after the treatment, the afternoon is likely to return to the sound. In addition, the first two methods of l, 2 increased expenditure and labor time; the third method will affect the service life of the belt, but also affect the service life of the water pump, generator bearings; the fourth method also affects the service life of the belt. Therefore, some drivers in a few times to deal with the effect is not good, that cost labor and money and can not solve the problem, anyway, only noise, no other harm, just let it go!

3. The use of "microwave-shaped groove pulley" to cure the fan belt ring

According to the above methods used to rule out the fan belt ring and the effect of analysis, it can be affirmed that the reason for the noise is the fan belt and belt groove slipping each other caused by the key is the fan belt on both sides of the working surface of the rubber quality! The key is the fan belt on both sides of the working surface of the rubber layer lost a good coefficient of friction and can not long maintain the good elasticity of the rubber, and the cause of such a consequence is the working surface of the rubber surface layer of the long term in the conventional belt groove in a V-shaped diagonal flat geometric shape of the groove by the extrusion of the more and more smooth and the occurrence of the hardening tendency of the results.

Analysis to this point, another problem arises, that is, the larger displacement engine is also commonly used triangular fan belt, only the type of triangle belt is "A" type or larger "B" type, and then the use of the pulley groove at The diameter of the pulley is larger. Why is it that fan belt rattling is rare? Comparative analysis can be seen:

"A" type or "B" type triangle belt working surface is wider ("B" type is wider than "A" type, "B" type is wider than "A" type, "B" type is wider than "A" type, "B" type is wider than "A" type, "B" type is wider than "A" type. "Type", "A" type is wider than "O" type), the diameter of the pulley is larger, so the two contact area is larger, the torque can be transferred to the ability to large; engine displacement is generally lower maximum speed, the fan belt used ("B" type) larger cross-sectional area. Triangle belt) cross-sectional area is larger, so the fan belt work when the possibility of vibration is small, the possibility of slippage is small; because the maximum speed of the engine with a "B" type triangle belt is relatively low, so that the water pump, generator, air compressor and other accessories from idle to high speed when the speed of the work of the time ratio of the rise is small, the time of the process of change is slow, so the fan belt slippage is small. So the possibility of fan belt slippage is smaller. As a result of these differences and impact, making the larger displacement engine in the use of "B" type fan belt rarely occurs when the fan belt ring phenomenon. Moreover, low-displacement engines are not suitable for the use of "B" type triangular belts as fan belts due to their smaller dimensions to overcome the problem of fan belt rattling.

The microwave groove pulley has a simple structure and is easy to manufacture; it does not change the original structure of the car and does not affect the service life of the belt; and it is effective in eradicating the problem of fan belt rattling in the long run.