Build a real working gearbox (speed and torque/force demonstration) with this DIY motor and gearbox kit .
This is one of the coolest science kits I carry. This working gearbox kit demonstrates a real gearbox attached to an electric motor. The gearbox has various gearshift cogs which shift function by changing the occlusion of different gears inside the gearbox using the stick shifter.
How gears work
A gear is really just a lever. Gears transmit power from one part of a machine to another. Think of the link between the pedals of a bike and the turning of the wheels or the motor in a car driving the transmission which drives the wheels. The collection of gears (like in a transmission) is called a gearbox.
The gearbox can contain any number of gears, in different shapes and sizes, all linked together. When power passes from one gear to another, one of three things can occur:
- Increase speed: If you connect two gears together and the first one has more teeth than the second one, the second one (the smaller gear) has to turn round much faster to keep up. The second gear turns faster than the first one but with less force (less torque). This is equivalent to a high gear on a bike or car.
- Increase force: If the second wheel in a pair of gears has more teeth than the first one (i.e. it’s a larger gear), it turns slower than the first one but with more force (more torque). This is equivalent to a low gear on a bicycle or car.
- Change direction: When two gears mesh together, the second one always turns in the opposite direction. So if the first one turns clockwise, the second one must turn counterclockwise. You can see this change in direction in the animation below.
This gearbox kit includes the following parts:
- Project board
- Belt pulleys (wheels)
- Battery box and wire
- DC motor
- Motor fixture
- Square pillars for elevating the battery holder above the project board
- Wooden boards for gearbox frame
- Various gears (single layer gear, dual layer gear, long main gear, main gear, worm gear)
- Shaft carriers
- Screws (4mm, 6mm, 7mm)
When assembled, this kit is very durable letting you reuse it over and over again for demonstration purposes or set it on your desk as a conversation piece.
Check out the video below which show this gearbox kit in action.