Speed Ratio Calculator

Formula

To calculate the speed ratio:

\[ \text{SPR} = \frac{\text{OG}}{\text{IG}} \]

Where:

\(\text{SPR}\) is the Speed Ratio
\(\text{OG}\) is the number of teeth in the output gear
\(\text{IG}\) is the number of teeth in the input gear

What is Speed Ratio?

The speed ratio refers to the ratio of the number of teeth on the output gear to the number of teeth on the input gear in a gear system. It determines how the rotational speed of the input gear is transformed into the rotational speed of the output gear. For example, if the input gear has 10 teeth and the output gear has 30 teeth, the speed ratio would be 3:1, meaning the output gear turns at a third of the speed of the input gear, but with increased torque.

Example Calculation 1

Let's assume the following values:

Number of Teeth in Output Gear (OG) = 60
Number of Teeth in Input Gear (IG) = 20

Using the formula:

\[ \text{SPR} = \frac{60}{20} = 3.00 \]

Speed Ratio: 3.00

Example Calculation 2

Let's assume the following values:

Number of Teeth in Output Gear (OG) = 25
Number of Teeth in Input Gear (IG) = 50

Using the formula:

\[ \text{SPR} = \frac{25}{50} = 0.50 \]

Speed Ratio: 0.50