Combining Gears

In this hands-on activity, we build a complex gear assembly to demonstrate how gears manipulate motion—whether increasing speed, changing torque, or redirecting motion across axes.

1. Compound Gear on a Common Axis

A compound gear consists of two gears of different sizes fixed on the same axle. When the small gear drives a larger one (or vice versa), it creates a gearing ratio that changes output speed and torque.

2. Speed Increase via Crank and Gears

By connecting a crank handle to turn a larger gear that meshes with a smaller gear, the output turns faster than you crank. This is how speed multiplication works: the ratio is equal to the tooth count of the large gear divided by that of the small gear.

3. Bevel Gear for Axis Change

Adding a bevel gear allows motion to be transferred at right angles—for example, horizontal rotation becomes vertical rotation. This demonstrates how gear systems can change the direction of motion without complex joints.

4. Putting It All Together

Combining compound gears, cranks, and bevel gears in one assembly showcases several essential mechanical principles:

• Speed adjustment through different gear ratios

• Torque modulation—gears trade force for speed or vice versa

• Axis reorientation using bevel gears

• Smooth, efficient power transmission

This gear setup is ideal for exploring the basics of mechanical advantage, kinematic chains, and the design of gear trains. It provides a solid foundation for anyone studying robotics, mechanical design, or automated machinery.