For a motor with an rpm of 1745 and a 4″ diameter sheave driving a 6″ diameter sheave, what is the output rpm?

To determine the output RPM of a motor with a sheave system, you can use the formula that relates the motor RPM, the diameters of the sheaves, and the output RPM. The relationship is based on the principle of conservation of speed in a belt drive system, where the torque is equal on both sides.

The formula to calculate output RPM based on the diameters of the sheaves is as follows:

Output RPM = (Input RPM) × (Diameter of Driving Sheave / Diameter of Driven Sheave)

In this scenario:

• The input RPM is 1745.

• The diameter of the driving sheave (4 inches) is attached to the motor.

• The diameter of the driven sheave (6 inches) is the one receiving the movement.

Plugging these values into the formula gives:

Output RPM = 1745 × (4 / 6)

Output RPM = 1745 × (0.6667)

Output RPM = 1163

This calculation shows that when the motor with a 1745 RPM is driving a smaller sheave of 4 inches in diameter to a larger sheave of 6 inches in diameter, the output RPM is indeed 1163. This reflects the way gearing works, where