1. What is Speed Ratio?

The speed ratio between two pulleys connected by a belt is determined by the ratio of their diameters. This relationship helps determine the output speed when the input speed is known, or vice versa.

2. How Does the Calculator Work?

The calculator uses the speed ratio formula:

Where:

• \( D1 \) — Diameter of the first pulley
• \( D2 \) — Diameter of the second pulley

Explanation: The speed ratio represents how many times the smaller pulley rotates compared to the larger one in a belt drive system.

3. Importance of Speed Ratio Calculation

Details: Calculating the correct speed ratio is essential for designing efficient mechanical systems, ensuring proper torque transmission, and achieving desired output speeds in belt-driven machinery.

4. Using the Calculator

Tips: Enter both pulley diameters in the same units (inches, millimeters, etc.). Both values must be greater than zero for accurate calculation.

5. Frequently Asked Questions (FAQ)

Q1: What units should I use for diameter measurements?
A: You can use any unit of measurement (inches, mm, cm), but both diameters must be in the same units for the ratio to be accurate.

Q2: How does speed ratio relate to actual rotational speed?
A: If you know the input speed, output speed = input speed × (D1/D2). The ratio directly determines how speed is transferred between pulleys.

Q3: Does belt type affect the speed ratio calculation?
A: The basic ratio calculation remains the same regardless of belt type (V-belt, timing belt, flat belt), as it's based on pulley diameters.

Q4: What if I have more than two pulleys in the system?
A: For compound drives, you would calculate the ratio step by step, multiplying the individual ratios between each pair of pulleys.

Q5: Can this calculator be used for gear ratios too?
A: While the principle is similar (ratio = driving/driven), gear ratios use number of teeth rather than diameter. For gears, you would input tooth counts instead of diameters.