Motors are in everything that runs around us: your car, oven fan, power tools, machinery, and many, many more things. Two different types of motors are in all of these machines. DC motors are direct current motors. The electrons in these motors go in one direction, and that's it. AC motors let current flow in different directions. The electrons can move both ways and do so at the same time.
DC motors have an extensive history going back to 1832. William Sturgeon invented the first DC motor that was powerful and stable enough to power machinery. Thomas Davenport is more well known for creating the DC motor because he patented it in 1837. At the time, the DC motor Davenport patented was too expensive and not powerful enough to stand up to the needed power. Many different people were trying to solve all the problems with DC motors, and in 1864, Anotino Pacinotti invented the ring armature, which was a crucial point of the DC motor. This stabilized it and made it capable of carrying power. Eventually, in 1886, DC motors were capable of maintaining a constant speed with variable loads. This is incredibly important to making the motors effective and used in commercial and residential spaces. DC motors are used in many industries now and have made the world so much more efficient.
The Parts of the DC Motor
Armature
This is the cylinder that includes magnets that turn the motor. It rotates on the axis.
Field Coil
The non-moving part of the motor that is wound to make a magnetic field
Brushes
The brushes of a DC motor are included in some DC motors but not in others. They are made with graphite and carbon and conduct current.
Commutator
Works with the brushes to conduct current. It is made of copper segments stacked together and supplies current to the armature.
This experiment requires some adult supervision. We are going to make a model of a DC motor using a battery and some wire. This is an experiment that I originally followed from Science Buddies on YouTube. I have changed it slightly, but the steps are very similar to their YouTube video, which is linked here. I would recommend watching the video for a visual aid to go along with the steps.
The Materials
Small neodymium magnets, approximately 1/4" or 6mm in diameter
Enamel-coated magnet wire (exact gauge is not critical)
D batteries
Jumbo metal paper clips (not plastic coated)
Electrical tape (other types of tape will work)
Fine-grit sandpaper
The Experiment
Bend the paper clips to make supports to hold the wire.
Tape the wire to the ends of the battery.
Wrap the wire around the marker to make a coil. Wrap it tightly and make sure all the coils are close to each other. Leave 3cm of wire on each end and loop the end around the coil to keep it wrapped. Make sure there are 3cm of wire on each side of the coil so it can rest across the battery in the paper clips.
Sand off half the covering on one side of the wire and completely
Thread the wire through the loops made by the paper clips so that it can spin freely.
Place a magnet under the wire loop and give it a push to start spinning.
Works Cited
Allain, Rhett. “Build a Simple Electric Motor | Science Project.” YouTube, 3 June 2019, https://www.youtube.com/watch?v=WI0pGk0MMhg. Accessed 21 November 2024.
“A Brief History of DC Motors.” Motor Specialty Inc., 20 May 2021, https://motorspecialty.com/news/a-brief-history-of-dc-motors/. Accessed 21 November 2024.
“DC Motor - Definition, Working, Types, and FAQs.” BYJU'S, https://byjus.com/physics/dc-motor/. Accessed 21 November 2024.
“The Engineer's Guide to AC vs DC Motors.” Fictiv, 21 September 2022, https://www.fictiv.com/articles/the-engineers-guide-to-ac-vs-dc-motors-2. Accessed 21 November 2024.
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