1, draw the drawing first.
2. Cut the foam board into the main structure with a cutting machine.
3. Make the sealing roller with A4 paper.
4. Insert an iron label in the center of the sealing roller.
5. Make a big drum with A4 paper.
6. Make the roller transmission structure
7. Put the roller into the roller drive structure.
8. The main structure is assembled in this way.
9. Use the roller made before to make the cover plate.
10. Assemble the prepared structures together and the production is finished.
Extended data:
The value of vacuum blackboard eraser;
Ordinary erasers will cause a lot of dust, which is composed of chalk and cooked gypsum powder, and then solidified by adding water. Chalk is a kind of limestone, mainly composed of calcium carbonate, which is soft and often used as a painting material.
Chalk and gypsum powder are in powder form, which is harmful to human health and can infect respiratory tract. Over time, it will cause respiratory diseases such as respiratory inflammation and asthma, and even endanger human health.
The vacuum blackboard eraser can suck chalk dust into the inner shell of the blackboard eraser to control the pollution of chalk dust. But also make full use of recyclable resources and avoid resource waste. The vacuum eraser greatly controls the pollution of chalk dust, which not only protects the health of teachers, but also protects students themselves and our lovely environment. It is cleaner and clearer than the traditional eraser.