Introduction: Temperature Guided Ventilator

It is always anoying when its hot outside and you have to leave the home, so you go outside and forget to put the fan on. When you get home its realy hot inside. So thats why I thought of this temperature guided fan. This fan has temparuture sensor that turns the van on when it gets to hot at home, the temperature is adjustible by your own input. The minimum temperature is 5 degrees Celcius and the maximun temperature is 30 degrees Celcius.

The project will involve:

  1. A laser cuter
  2. A 3D printer
  3. Soldering iron
  4. Wood (or some other material that you like and you can put inside a lasercutter)
  5. A velleman kit, for the temperature (*
  6. An electrical engine (*
  7. batteries 12V
  8. Tape

*Info about the velleman kit and the engine are in the .pdf files above

Step 1: Cut a Wooden Shape

first download the adobe illustrator file(.ai), this is the file that will go into the lasercutter the hole in the middle is for the engine. Note that the hole is 1 mm to small for the engine so you have to make it slightly bigger. I did this so the engine would fit verry tight. The wood I used is plywood(360x200 mm) You can use any material that you like, aslong as the lasercutter is able to deal with it.

After you cut the shape out you can put the engine in the middle, put some tape at the front of the engine and at the back around it. So the engine will not slight forwards or backwards.

You can use some sandpaper to remove the black burning marks from the lasercutter, but I think that the black edge gives the design a nice touch.

Step 2: Solder the Velleman Kit

Next you have to solder the Velleman kit, if you done so you must drill four holes of 3 mm to connect the module onto the fan. Connect the NTC on the marked spot, with the screw connector and connect the engine to the relay. The way you have to connect it is to put one wire of the engine on the min side of the battery and the other wire to the most right screw connector of the relay and the middle screw connector goes to the plus side of the battery.

if you want to know how the kit works read the text below, otherwise you skip it and continue building.

The way the Velleman kit works is with a comparator, the comparator check the reference voltage from the potentiometer and compares it with the voltage of the NTC resistor. If the voltage of the sensor is equal or higher than reference voltage than the output of the comparator will be high(1), otherwise low(0). The high signal goes to the base of the transistor. The the transistor will send a signal to the relay and the relay will switch on.

Note that I use the module in reverse and that the relay is always in the on position and when the relay goes off the engine will go on. You will see when you connect the batteries the engine will run for a half second.

Step 3: Create a Standard

Use some tape to connect the the 12V battery pack to the fan, put it on to see if the standard holds the engine. I created a propeller out of cardboard to see how the engine would perform with something on it.

Step 4: Print the Propeller

Download the .stl file in the description and print it, if you want to you can make the proppeller a little bit bigger in width but keep in mind that it will take longer to print. This design took 40 minutes to print.

Also the whole in the middle is a little bit to small for the engine so you need to drill it out. I did on purpose so the proppeller will fit verry tight.

Step 5: Finishing Touch

Finally you can modify the van to give it something unique, so I decided to remove all the tape and I sawed out two wooden shelfs, wich served as stand. Another thing I did was I found some old stuff in my home that could use, so I found a little handle and two bells from an alarm. Those things are not for sale so that makes mine van prety unique.