| 摘要 |
PURPOSE: Provided is an apparatus for wiping out characters written on blackboard with chalk that includes two cotton rods replaceable, a dusting rod and a vacuum suction device, which can clear the blackboard easily without raising chalk powder. CONSTITUTION: The apparatus comprises two cotton rods made of corduroy and rotated together from side to side, a toothbrush type of dusting rod having 2-3mm of brushes contacted to the cotton rods to wipe chalk powder stuck to the cotton rods, which is connected to a power gear and rotated fast in the opposite direction with the cotton rods, a dust port where chalk powder separated from the cotton rods and piled, and a vacuum suction device sucking the piled chalk powder to be collected in a storage bag.
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