Toys have a great role in children's mind development. It support positively to the children thinking ability and creativity. Most of the children dismantle the toy to some parts. It indicate their curiosity. This is because they need to know, how it's works. This enhance their creativity and thinking ability. So toys have a great role in children life. In my belief, every person have a children mind with out depending their age. I am a living proof for this. Because I love the toys still now. This curious mind is the force behind this instructable.
The toys are the starting point of our science journey. Every simple toy is work based on a simple science law, especially the physics. So every toy teach a new science lesson for us. So, here I make a simple (already available for you) toy for every toy lovers. It's name is "Simple Toy Motor". It is the simple model of the modern brushed DC motor. It will simply revel the working of the DC motor. It's making is very simple and the components needed is easily available for every person. It is very interesting one. So first we going to move 'how it is made' and after it, we discuss about the 'theory for its working'. OK. So lets starts now.....
Step 1: Basic Plan
For a DC motor working we need a coil (rotor) and a magnet (stator). For stator magnet we use a round magnet from old speaker. The coil is made with out a core by using enameled copper wire. Then the main setup needed to work the motor is the brush and commutator setup. It makes the motor to run continuously, by making a variable magnetic field. This setup is made by the extra length of the copper wire from the coil. And it also act as the motor shaft. The whole setup is placed in a hylam sheet. Give an extra low voltage dc for its operation from a battery. This is our planning. So first we make the coil and then we going to make the stand. OK. Let's start now....
Step 2: Materials Needed
The materials needed for this project is not expensive. The material list is given below,
Round magnet - 1 (Taken from an old speaker)
Enameled copper wire - ( take it from an old transformer or any inductive type equipment)
Small screws and washer - 2
Thick Copper wire (I taken a waste piece of earth conductor)
Plastic stickers (different colors)
Double side sticky tape
Instant glue (i use Flux Quick)
The above figure shows the material images.
Step 3: Tools Needed
The tools used by me is shown in this list. You use tools comfort for you. OK.
Hack saw blade
Step 4: Coil Winding
Our first step is to make the stator coil. We make it without using a core materials. This is because we going to make the simple model. So we neglect the iron core which is present in the practical motors. That is, here made an air core coil. I make about 10 turns, because higher number of coil increase the weight. The perfect round shaped coil is made by using a plastic bottle. Then for sticking it together apply some glue. The complete procedure is given below,
- Take an enameled copper wire which have required length
- Straighten it by using hand or pliers
- To make the round coil, wrap it around a cylindrical plastic bottle of diameter 3 c.m.
- Make 10 turns in the bottle
- Remove the bottle with care to avoid the unwinding of coil
- Apply instant glue to stick the coil together
- Wait some time for drying it
- Then take the two ends of the wire from two opposite sides of the coil
- Cut unwanted length from 2 ends ( need 3.5 c.m. from the coil)
We done the coil making.
The full procedure is given in the above figures.
Step 5: Commutator Making
Here in this step I explain the making of commutator. It is an essential part in the DC motor. It helps to change the magnetic field polarity by changing the current direction. In practical sense it is little bit complex. But here make it in simple method. It is made by removing the insulation coating in 180 degree out of the full 360 degree of the enameled copper wire. That is, remove insulation from half of the portion. In this model this commutator also act as the shaft of the motor. The complete procedure is given below,
- Straighten the wire leads by using a pliers
- Balancing of the coil by changing the bending of wire for vibration free rotation of the coil
- Apply some glue to the bending to keep it in position
- Wait for the drying process
- Remove the insulation coating from two ends at half of its surface by using a small knife (refer the images and video)
We done the commutator making. The images are given above.
Step 6: Brush Making
Here explain the making of brush setup. But here the brush helps to hold the coil in its position. In original motor it only use to supply the current to the coil. Here for simplicity, I used it to supply current and support the coil. It made from a copper earth conductor piece. Two circular shapes are created at one end for placing the rotor coil on it. The other end bend in a square shape for screwed it into the base structure. The complete procedure is given below,
- Take a thick copper wire
- Straighten it by sing hammer and pliers
- Clean its surface by using sand papers
- Cut 2 pieces of length 5.5 c.m.
- Bend its 2 ends like in the above images (final effective length is 4.5 c.m.)
Completed the brush making. Images are given above.
Step 7: Base Making
I use a hylam sheet for making the base. The base is used to place the whole motor setup. The brush is screwed to the base. The needed holes are the 2 end holes. Other holes present in the image is not needed. It is made by me in the past projects. The procedure is given below,
- Take a 9 c.m. x 7 c.m. hylam sheet
- Make two hole at the ends by using drilling machine
- The brushes are screwed to the holes
- Take double sided sticky tape and cut into small pieces
- Stick the pieces under the hylam sheet to form a stand
We done all the base works.
Step 8: Connecting the Magnet
Here I use a round magnet from old speaker. It is placed at the center of the two brushes. I use a 5 c.m diameter and 1 c.m thick magnet. The magnet is stick to the hylam sheet by using double sided tape. Then place the coil in the brushes and ensure that the coil is freely rotate without any problem. The images shows the full procedure.
Step 9: Connecting the Wires
Here I made physical connection to the brushes of the motor to connect it into a battery.
- First take some wires
- Strip its end
- Unscrew the screw which connect the brush to the hylam and place stripped wire to it and screw tightly
- Apply some instant glue to fix the wires at its position
We done the successfully. All are well given in the above images.
Step 10: Some Art Work
Here I add some art work to the base structure for beauty. For this I use plastic stickers, commonly these are used for vehicles. By using this stickers I make some art work. I don't know it increase or decrease the beauty. I believe it increase the beauty of the product. You done your own work. OK. Best of luck.
Step 11: Final Assembling & Testing
Place the coil in the brushes. Now we complete the toy motor project. For testing connect a 3.7 V Li-ion battery or a 9 V battery. 3.7 V battery provide more speed because it deliver more current than the 9 V battery. After connecting, If it is not stat rotation then you start the motor by rotate slowly using the fingers. Now the motor work very well. If not working check the connection and the coating removed portion of the coil. The above images shows the finished toy motor.
Step 12: Theory Behind the DC Brushed Motor
The above figure shows the schematic of a DC brushed motor. The parts are marked in that and please compare it with our toy motor. The working is given below in simple points.
- When connect the battery, current is flowing through the coil
- When current flowing through a coil, it produce magnetic field (polarity based on the direction of current flow (right hand thump rule))
- This magnetic field produce by coil attract and opposes by each magnets and a force is created
- Due to the force the coil rotate and align with the opposite poles of magnet and coil
- But in this time the commutator changes the current polarity
- So the produced magnetic field direction changes to opposite
- So the coil again rotate for the stable alignment
- This continue and rotate in a continuous manner
This is the working of brushed DC motor. Basically work by attraction and repulsion of two magnets. One is the electric magnet (coil), it changes its polarity while rotating. This produce the rotating effect. I believed that you understand this. OK. How is it ? Are you like it ? Please comment me.
Bye.....see you in the next project..