What Are Gears?
Wind turbine gearbox. Image is from globecore.com
Cleaning a wind turbine gearbox. The image is from stingraypartswasher.com
What are gears? Gears are wheels with teeth. A gear train is made of several gears that mesh together.
On a wind turbine, a gearbox is typically used to increase rotational speed from a low-speed shaft where the blades are connected to a higher speed electrical generator.
In today's session, we will welcome Ralph Pugh, a Makersmiths member with an engineering background, to help us understand the different kinds of gears, their functions, and how using gears in our KidWind wind turbine will benefit its performance. His presentation is entitled, Understanding Gears, Fun with Gears.
Key vocabulary to know:
- driving gear is the one connected to the wind turbine blades
- driven gear is the one connected to the generator
- gear ratio (driving gear teeth): (driven gear teeth)
- shaft is the rod that connects the wind turbine blades to the gear box that connects the gears in the gear box to the generator.
- Purpose of gears: Changes speed, direction of motion, torque (force). In a wind turbine, gears change speed.
Below you will find videos and images from our session on gears and their functions.
In KidWind Challenge sessions, students learn about the function of gears. In this clip, we begin our gear session by considering how gears on a bike are used to help us easily peddle up a hill and go fast when on a level roadway. To learn more about how the gears work on a bike for going up and down hills or peddling fast on level ground, see https://adventure.howstuffworks.com/outdoor-activities/biking/bicycle4.htm
When we think of gears, we usually think of them being round, like a wheel but they also have teeth. However, as demonstrated in this video clip, gears can be square or even oval!
What happens when gears are meshed together? In this video, KidWind team members learn about driving gears, driven gears, and understand "linkages." They learn for one rotation of the larger gear, the smaller gear turns faster and makes more than one rotation. This is an important concept because when creating a wind turbine, they want the gear that makes the blades rotate to do so at a slower, safe speed. They want the gear that makes the generator spin to do so at a faster speed in order to produce more energy.
In this final clip, our KidWind team members learn how more than one gear on a shaft can work to turn the blades and the generator. The team members must consider how they might go about arranging gears on two shafts so that their turbine's generator can produce desired amounts of energy.
Just for fun, the KidWind Team members ended the session with a Creepy Bot race. They guessed that the dragon would win the race, thinking its long legs would put it at an advantage. But... watch what happens.
Learn to create your own gears with Gear Generator.
Testing out gearboxes. In this lesson, our KidWind participants learned about 1:4 and 1:16 gearboxes to measure and compare the power from the generator at different speeds.
What will happen if we try a 1:24 gearbox? Let's find out.
Ralph Pugh's lesson on creating a gearbox for the wind turbine: https://docs.google.com/presentation/d/1S5BmiaaFF2LK3F0ZJJlAdv-oW8g_tnjV9F2M5-GBtDE/edit?usp=sharing