| 摘要 |
PROBLEM TO BE SOLVED: To shorten a stroke of a cylinder. SOLUTION: A driving shaft 3, an inner cylinder 4 and an outer cylinder 5 are concentrically inserted in a housing 1 fixed on a frame. A cylinder 11 is fixed to the outer cylinder 5, and the rod end of the cylinder 11 is connected to a mount bracket 9 on which a motor for rotating the driving shaft 3 is to be mounted. When the cylinder is extended or contracted, the driving shaft 3 is raised or lowered through the mount bracket 9, and also the brush part is raised or lowered. While, in a case where the brush is worn and polishing pressure is lowered, if a decelerator provided motor 19 is rotated, the outer cylinder 5 is raised or lowered since a screw shaft 21 connected to the motor is fitted to a nut 24 on a support plate 23 attached to the outer cylinder 5. Since the cylinder 11 secures only a stroke required for carrying-in and out of a work piece, the cylinder 11 may have the small size. |
