flat belt

V-belt

Poly V-belt

round belt

Simple structure

low price

Smooth transmission

Buffering and vibration absorption

Slip during overload to prevent damage to other parts

Transmission ratio is unstable

The overall dimensions of the transmission are larger

Less efficient

Belt life is shorter

Greater stress on the shaft due to belt tension

Medium and small power transmission (not exceeding 50kW)

In multi-stage transmission systems, it is often used in high-speed stages

Mostly used in occasions with large center distance

The difference in tension between the two sides of the belt is called the effective tension of the belt drive, which is the circumferential force transmitted by the belt. It is the sum of the frictional forces on the contact surfaces of the belt and the pulley.

When the power of the belt drive exceeds this limit, significant relative sliding will occur between the belt and the pulley, a phenomenon called slipping. Slippage will cause serious wear and tear of the belt. Slippage should be avoided during belt transmission.

Initial pulling force (the greater the initial pulling force, the greater the maximum circular force)

Wrapping angle a (the larger a, the greater the maximum circular force)

Friction coefficient f ((the greater the friction coefficient, the greater the maximum circumferential force)

This kind of sliding between the belt and the pulley caused by the elastic deformation of the belt is called the elastic sliding of the belt. This is an inherent characteristic of the normal operation of the belt drive and cannot be avoided.

i=n1/n2=d2/d1/(1-e)

Ordinary V-belt

Narrow V-belt

Wide V-belt

Joint V-belt

Large wedge angle V-belt

Material

structure

Selection

Determine the reference diameter of the pulley and calculate the belt speed

Determine the center distance and reference length of the V-belt

Check the wrapping angle of the small pulley

Determine the number of strips

Tighten the belt by adjusting the center distance

Tension with tension wheel

When installing the belt drive, the two shafts must be parallel and the grooves of the two pulleys must be aligned.

Protective cover should be added

When the V-belts need to be replaced, the same set of V-belts should be replaced at the same time, and old and new ones cannot be used together.

The tape should not be in contact with acid, alkali or oil; the working temperature should not exceed 60°

Stable transmission, accurate transmission ratio, etc.

Both manufacturing and installation require higher precision and higher costs

Large equipment such as medium and small power transmissions or compressors that require accurate transmission ratios

No elastic sliding and slipping phenomena, ensuring accurate average transmission ratio

High transmission efficiency

The chain does not need to be tensioned very tightly around the pulley like a belt

Compact structure

Can work in high temperature, low speed and oily environments

Low installation accuracy and low cost

The structure is lightweight when the center distance is large

The instantaneous chain speed and instantaneous transmission ratio are not constant, so the smoothness of the transmission is poor, and there is impact and noise during operation.

Transmissions in mining machinery, agricultural machinery, petroleum machinery, and motorcycles

The two axes should be parallel, the two wheels should be on the same plane, and the inclination angle with the horizontal plane should not exceed 45°.

When the transmission center distance is adjustable, the tension can be controlled by adjusting the center distance.

When the transmission center distance cannot be adjusted, a tensioner wheel can be installed or 1-2 links can be removed from the chain after it is worn and stretched.

Significance: Good lubrication can reduce wear and noise and extend chain life

Method: Select from the relevant design data based on the chain speed and chain pitch.