Dust collector for teaching

Abstract

The invention discloses a dust collecting device for teaching. The dust collecting device for teaching comprises a chalk sleeve. The chalk sleeve comprises a shell, internal threads, threaded silica gel, a screw rod and a dust collecting device body. The shell is of a long strip hollow structure, and comprises a first shell part and a second shell part connected end to end in a length direction of the shell; the internal threads are arranged on inner side walls of the shell; the threaded silica gel and the internal threads are in mosaic distribution and distributed on the inner side walls of the shell; the screw rod is in threaded connection with the shell; the dust collecting device body is a long strip slot body with an opening on the upper end, and is horizontally arranged on a writing face of a blackboard; two ends of the dust collecting device body are in sliding connection with two side edges of the blackboards; and the surface of the dust collecting device body and the blackboard have the same color. According to the dust collecting device for teaching provided by the invention, the chalk sleeve used for fixing a chalk to write in a sleeving way is provided for a user, so that a hand of the user cannot be polluted; and in addition, the dust collecting device body can synchronously collect scattered chalk dust while the user is writing, so that pollution cannot be caused to the indoor environment.

Description

technical field [0001] The invention relates to the technical field of teaching aids, in particular to a dust collecting device for teaching. Background technique [0002] Chalk is a tool widely used in daily teaching. It is generally used to write on blackboards. The composition of chalk is a white precipitate of calcium sulfate, which is not easy to be decomposed, and the particles are larger than dust. Now, the chalk used in China mainly contains two kinds of common chalk and dust-free chalk (water-based chalk). Dust-free chalk is made of special polymer materials and pigments. It can be written on a dry blackboard or a wet blackboard. However, in order to prevent dust when writing, its adhesion and The firmness on the blackboard, therefore, dry erase is not easy to fall off, and its cost is higher than ordinary chalk, and universal applicability is lower. [0003] In addition, the common way to use ordinary chalk is to directly hold the chalk for writing. On the one ha...

AI Technical Summary

Problems solved by technology

Dust-free chalk is made of special polymer materials and pigments. It can be written on a dry blackboard or a wet blackboard. However, in order to prevent dust when writing, its adhesion and The firmness on the blackboard, therefore, dry erase is not easy to fall off, and its cost is higher than ordinary chalk, and its universal applicability is low

[0003] In addition, the common way to use ordinary chalk is to directly hold the chalk for writing. On the one hand, when the chalk is relatively long, it is easy to break; Replacement, the discarded chalk heads are really a waste of resources

And because the chalk contains high alkalinity, it has also caused certain pollution to the user's skin after being handled for a long time, and the silt on its surface is also easy to stick to the surface of the clothes, which is not easy to carry

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