During the winter, when we work long hours at our computers, it is very convenient to have a device where we can heat up a cup of coffee or some other hot drink. In today's article, we will look at how to make a USB beverage warmer that we can connect to our PC in a simple and quick way, taking advantage of the "Joule effect which is generated by passing electric current through a series of resistors.
To make our USB drink warmer, we will need the following materials:
- USB cable.
- USB connector.
- A switch.
- A faulty microprocessor (the bigger the better).
- Three 1W 4.7 ohm resistors.
- Thermal paste.
- Thin cables for making connections.
- A wooden or thick cardboard box large enough to hold our mug.
Construction of the USB beverage warmer
The first thing we are going to do is to make a series arrangement with the three resistors, which we will join with the help of a tin soldering iron. Once the series arrangement has been made, we will connect the free end of the third resistor to one of the switch connectors.
Once the switch is connected to the array in series, we connect the output of the switch to the input-ground of the USB connector, while the free end of the first resistor is soldered with the help of a wire to the +5v input of the connector. USB (the red wire is the +5v wire, and the black wire is the - ground wire).
After the electrical assembly, we start with the assembly of the heater, for this, we make the necessary holes to place the switch, the cup to be heated and to take out the cable. USB. Remember that the hole where the cup will be placed must be big enough to fit into the box.
We fix the switch to its hole, using adhesive tape or silicone if necessary. Next, we fix the array of resistors in series, taking care that it is just below the hole for the cup. Once this is done, we put thermal paste on the bottom of the microprocessor and place it on top of the resistors.
Now all that's left to do is to pull out the cable through its respective hole, close the wooden box and connect it to the PC to enjoy our beverage warmer. USB.
How it works
The electricity flowing through the resistors when the circuit is opened generates heat by "Joule effectwhich is dissipated to the outside. By using thermal paste, we encourage heat transfer to the conductive plate (microprocessor) which, when heated, will transfer heat to the cup we place on top of it, keeping our drinks warm.