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Spur Gear Module Calculation Formula

Spur Gear Module Formula:

\[ m_{spur} = \frac{P}{\pi} \div \tan(\alpha) \]

mm
degrees

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1. What is the Spur Gear Module Formula?

The spur gear module formula calculates the module of a spur gear based on its pitch and pressure angle. The module is a fundamental parameter in gear design that determines the size and spacing of gear teeth.

2. How Does the Calculator Work?

The calculator uses the spur gear module formula:

\[ m_{spur} = \frac{P}{\pi} \div \tan(\alpha) \]

Where:

Explanation: The formula calculates the module by dividing the pitch by pi and then dividing the result by the tangent of the pressure angle.

3. Importance of Spur Gear Module Calculation

Details: Accurate module calculation is crucial for proper gear design, ensuring correct tooth size, spacing, and meshing with other gears in mechanical systems.

4. Using the Calculator

Tips: Enter pitch in millimeters and pressure angle in degrees. Both values must be positive numbers (pitch > 0, angle between 0-90 degrees).

5. Frequently Asked Questions (FAQ)

Q1: What is the module in gear terminology?
A: The module is a measure of the tooth size of a gear, defined as the ratio of the pitch diameter to the number of teeth.

Q2: What are typical pressure angle values for spur gears?
A: Common pressure angles are 14.5°, 20°, and 25°, with 20° being the most widely used in modern gear design.

Q3: How does module relate to gear size?
A: Larger module values indicate larger teeth, which generally means the gear can transmit more torque but may operate at lower speeds.

Q4: Can this formula be used for other gear types?
A: This specific formula is designed for spur gears. Other gear types (helical, bevel, worm) have different calculation methods.

Q5: Why is the tangent function used in this formula?
A: The tangent function relates the pressure angle to the geometry of the gear teeth, specifically the relationship between the pitch and the tooth dimensions.

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