A transfer conveyor belt is usually driven at a low constant speed. Accordingly, a gear head induction motor with a reduction ratio of 60:1 is selected here as a driving power source. To transmit this driving power efficiently to the flat belt pulley for driving the conveyor belt, a chain-driven power transmission system (Photo 1) is applied here:

(1) Characteristics Comparison between Chain-Driven Transmission System and Other Systems

The table below shows the comparison of typical power transmission systems. A chain-driven power transmission system is selected here for high transmission efficiency and ease of design (with high flexibility for the design of two shafts space distance):

(2) Sprocket chain design method

Explanation of the load calculation method is omitted here because of the low speed and not-heavy transmission load on a sprocket chain. The number of sprocket-teeth and the number of chain links can be determined according to the procedure below. A safety cover over the chain is required.

1. Determine the distance between the motor shaft and the flat belt driving pulley shaft.
2. Determine the ratio of the number of teeth on the two sprockets (speed ratio).
3. Determine the number of teeth on the smaller sprocket. <See the note below>.
4. Determine the number of teeth on the larger sprocket from the speed ratio.
5. Select a product series from the sprocket chain catalog.
6. Use the formula below to calculate the number of chain links corresponding to the chain length <See FACE Technical Datasheet p. 1498−8>.
7. Round up the calculated value to the nearest integer to determine the number of chain links. After drilling long holes for base fixing in the motor mounting bracket, adjust chain tension during assembly.

-Example

When distance between the motor shaft and pulley shaft = 100 mm, sprocket teeth ratio = 1:1, and number of teeth = 32: