Coffee bean roasting system transformed from popcorn machine

Modification materials:

1, small popcorn machine, plus postage 90 yuan have change.

2, aluminum foil cover, is to replace the original plastic windshield, the original that can not withstand the high temperature of more than 200 degrees Celsius, melted during the test.

3. Arduino controller.

Temperature sensing module, used to monitor the real-time temperature inside the machine.

5. Relay module. It is used to control the current on-off.

6, stainless steel bowl, used to collect the "silver flakes" produced during the baking process

The following is the player's introduction:

The red machine is a small popcorn machine purchased on Taobao, plus postage 90 yuan.

The aluminum foil cover on the popcorn machine replaces the original plastic windshield. The original one could not withstand the high temperature above 200 degrees Celsius. It melted during the test.

Next to the blue large circuit board is an Arduino controller used for programming control, Taobao can also buy.

The green part of the circuit board is the temperature sensing module, which is used to monitor the real-time temperature inside the machine.

The red circuit board is a relay module, which is used to control the current on and off. I also have a similar model hidden inside the popcorn machine.

The stainless steel bowl below is used to collect the "silver dust" produced during the roasting process (the inner peel attached to the coffee beans, which will separate from the beans after roasting). Don't underestimate it. This bowl is the most expensive single part of the whole system-MUJI, brand goods, 100 counties ocean drop work…=bbb

The curve of temperature climb, the horizontal axis is time (minutes), the vertical axis is temperature (degrees Celsius), in fact, there is a rapid increase to 100 degrees at the beginning, and finally there is a rapid cooling, which is not shown here. The orange curve is the actual temperature detected, and the black curve is the set point. It can be seen that the maximum error is 5-6 degrees, and there is room for improvement in control accuracy.

Lift the foil lid--baking bin is also. 50g of coffee beans are placed here, just covering the vent hole at the bottom of the barrel, and the hot air ejected from it is the heating source. The white wire is the thermocouple probe responsible for temperature measurement.

The silver from the previous baking test wasn't wiped clean. It was cold and dry. Static electricity made these little things very annoying. Before, I had to dust, sweep the ground and wipe the table every time I baked them. Until I added an aluminum foil deflector and shot them all into a wet bowl.

"All, all of them came in…Good, good warm feeling…" Cover your face and escape>_