| 摘要 |
PURPOSE:To prevent a fine dust of abrasion from flying about in a room by providing a dustproof cover with a bellows-type shell part which expands and contracts with flat surface parts, which are facing each other by means of a circular bend, separated from each other and a connecting member having an air vent passage for ventilating the air in the bellows. CONSTITUTION:A dustproof cover 1 is comprised of a bellows-type shell part 2, which is placed in such a manner that it expands and contracts with flat surface parts, facing each other by means of a circular bend whose sectional form of a top part 21 and a valley part 22 is formed into the shape of a circular-arc with a prescribed radius, separated from each other, and connecting members 30, 31 which are juxtaposed on the edge of the bellows-type shell part 2, and provided with an air vent passage for enabling the air in the bellows-type shell part 2 to be ventilated. Therefore, even if the bellows-type shell part 2 expands and contracts by virtue of a reciprocating stroke of a piston rod 4, no part in the peripheral surface of the bellows-type shell part 2 comes in contact with each other during its operation, and accordingly, dusts of abrasion cannot be produced and the static electricity cannot be generated. In addition, since the air in the bellows-type shell part 2 is ventilated only through the air vent passage, dusts of abrasion and oil in the sliding part are discharged outside a clean room. |
