A cleaning unit, comprising: a columnar body portion in which a rotation guide hole is disposed on an outer peripheral surface thereof; a shaft (220, 320, 420, 520) provided to reciprocate a predetermined distance in a length direction of the shaft (220, 320, 420, 520) in a hollow disposed in the body portion; a driving portion protruding from the shaft (220, 320, 420, 520) in a radial direction; a brush portion having one side provided on an outer peripheral surface of the body portion along the length direction to rotate with the one side as a rotation axis thereof; and a driven portion extending from the brush portion toward the driving portion to be inserted into a rotation guide groove disposed in the driving portion through the rotation guide hole, wherein the body portion comprises: a hollow body member disposed with a recess groove on which the brush portion is provided on an outer peripheral surface thereof, both ends of which are open; and a first end cap and a second end cap respectively fitted to both ends of the body member to cover the both ends, respectively, wherein both sides of the shaft (220, 320, 420, 520) are slidably coupled to the first end cap and the second end cap in the length direction, wherein the rotation guide groove extends at a predetermined angle with respect to the length direction of the shaft (220, 320, 420, 520), and wherein as the shaft (220, 320, 420, 520) reciprocates, the driven portion is guided to rotate by the rotation guide groove, and the brush portion is rotated by the rotation of the driven portion. a columnar body portion in which a rotation guide hole is disposed on an outer peripheral surface thereof; a shaft (220, 320, 420, 520) provided to reciprocate a predetermined distance in a length direction of the shaft (220, 320, 420, 520) in a hollow disposed in the body portion; a driving portion protruding from the shaft (220, 320, 420, 520) in a radial direction; a brush portion having one side provided on an outer peripheral surface of the body portion along the length direction to rotate with the one side as a rotation axis thereof; and a driven portion extending from the brush portion toward the driving portion to be inserted into a rotation guide groove disposed in the driving portion through the rotation guide hole, wherein the body portion comprises: a hollow body member disposed with a recess groove on which the brush portion is provided on an outer peripheral surface thereof, both ends of which are open; and a first end cap and a second end cap respectively fitted to both ends of the body member to cover the both ends, respectively, wherein both sides of the shaft (220, 320, 420, 520) are slidably coupled to the first end cap and the second end cap in the length direction, wherein the rotation guide groove extends at a predetermined angle with respect to the length direction of the shaft (220, 320, 420, 520), and wherein as the shaft (220, 320, 420, 520) reciprocates, the driven portion is guided to rotate by the rotation guide groove, and the brush portion is rotated by the rotation of the driven portion. a hollow body member disposed with a recess groove on which the brush portion is provided on an outer peripheral surface thereof, both ends of which are open; and a first end cap and a second end cap respectively fitted to both ends of the body member to cover the both ends, respectively, wherein both sides of the shaft (220, 320, 420, 520) are slidably coupled to the first end cap and the second end cap in the length direction, wherein the rotation guide groove extends at a predetermined angle with respect to the length direction of the shaft (220, 320, 420, 520), and wherein as the shaft (220, 320, 420, 520) reciprocates, the driven portion is guided to rotate by the rotation guide groove, and the brush portion is rotated by the rotation of the driven portion.