How To Calculate Output Speed

Output Speed Formula:

\[ Speed_{out} = Speed_{in} \times \frac{Input\ Diameter}{Output\ Diameter} \]

Output Speed (RPM):

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1. What Is The Output Speed Formula?

The output speed formula calculates the rotational speed of a driven pulley or gear based on the input speed and the diameters of both input and output components. It's fundamental in mechanical systems involving power transmission.

2. How Does The Calculator Work?

The calculator uses the output speed formula:

\[ Speed_{out} = Speed_{in} \times \frac{Input\ Diameter}{Output\ Diameter} \]

Where:

\( Speed_{in} \) — Input rotational speed (RPM)
\( Input\ Diameter \) — Diameter of the input pulley/gear (inches)
\( Output\ Diameter \) — Diameter of the output pulley/gear (inches)

Explanation: The formula demonstrates the inverse relationship between diameter and speed - smaller output diameters result in higher output speeds, and vice versa.

3. Importance Of Output Speed Calculation

Details: Accurate speed calculation is crucial for designing mechanical systems, ensuring proper gear ratios, maintaining equipment efficiency, and preventing mechanical failures due to incorrect speed matching.

4. Using The Calculator

Tips: Enter input speed in RPM, input diameter in inches, and output diameter in inches. All values must be positive numbers greater than zero.

5. Frequently Asked Questions (FAQ)

Q1: Can this formula be used for both pulleys and gears?
A: Yes, the same principle applies to both pulley systems and gear systems where diameter ratios determine speed ratios.

Q2: What if I have metric measurements?
A: The formula works with any consistent unit system. Just ensure all diameter measurements use the same units (mm, cm, inches, etc.).

Q3: Does this account for slip in pulley systems?
A: No, this formula provides theoretical output speed. Actual speed may be slightly lower due to belt slip or other efficiency factors.

Q4: How does this relate to torque?
A: While speed increases with smaller output diameters, torque decreases proportionally to maintain power conservation (Power = Torque × Speed).

Q5: Can I use this for chain drives?
A: Yes, the same principle applies to chain drives where sprocket diameters (or number of teeth) determine the speed ratio.