ENGINEERING – MECHANICAL ENGINEERING CALCULATOR
Gear Ratio Speed
A precise tool.
What is the Gear Ratio Speed & How does it work?
A gear set transmits torque and rotational speed between shafts by meshing teeth. The number of teeth on each gear determines the mechanical advantage, commonly expressed as the gear ratio. A larger driven gear relative to the driver reduces speed but increases torque. The gear ratio (GR) is defined as the ratio of the driven gear’s tooth count (Ndriven) to the driver gear’s tooth count (Ndriver). This dimensionless value tells you how many turns of the driver are required for one turn of the driven gear. Because power (ignoring losses) is conserved, the output speed is the input speed divided by the gear ratio. Knowing the tooth counts and the input speed lets you predict the driven shaft’s speed instantly.
GR = frac{N_{driven}}{N_{driver}}quadtext{and}quad N_{driven,speed}=frac{N_{driver,speed}}{GR}
GR = gear ratio, Ndriven = teeth on driven gear, Ndriver = teeth on driver gear, Ndriver speed = input rpm, Ndriven speed = output rpm
Parameters
Result
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Frequently Asked Questions
How do I calculate the gear ratio?
The gear ratio is calculated by dividing the number of teeth on the driven gear by the number of teeth on the driver gear.
What does a higher gear ratio mean?
A higher gear ratio means that the driven gear has more teeth than the driver gear, resulting in greater torque and slower speed.
How do I determine the speed reduction with a gear set?
To determine the speed reduction, divide the number of teeth on the driver gear by the number of teeth on the driven gear.
Can you explain how gear ratio affects torque?
A higher gear ratio increases torque because more force is applied to the output shaft for each rotation of the input shaft.
What happens if I reverse the gears in a gear set?
Reversing the gears will invert the gear ratio, increasing speed and decreasing torque.
How do I choose the right gear ratio for my application?
Choose a higher gear ratio for applications requiring more torque and lower speeds, and a lower gear ratio for higher speeds with less torque.
What is the relationship between gear ratio and mechanical advantage?
The gear ratio directly determines the mechanical advantage; a 2:1 gear ratio means you get twice the output force for each input force rotation.
Results are for informational purposes only and do not constitute professional advice.