| 摘要 |
PURPOSE:To prevent a scratch mark from being formed on a polished surface due to shifting at the time of starting polishing by giving a turning force to a workpiece while supporting it via an outer cylinder which is rotatably fitted on an inner cylinder rotated in the same direction as a surface plate via a bearing at the start of the rotation of the surface plate. CONSTITUTION:Plural rotary supporting stands 3 are provided on a circle having a common center with surface plates 1, 2 in the peripheral direction at an interval smaller than the diameter of a workpiece W and their inner cylinders 3A are rotated in the same direction as the surface plates 1, 2. The workpiece W is installed with a part of it being held between the surface plates 1, 2 while with a part being placed on top of the outer cylinders 3B of the rotary supporting stands 3 and, as the surface plates 1, 2 are rotated, the inner cylinders 3A also start to be rotated while the outer cylinders 3B are rotated at a speed lower than the rotation of the inner cylinders 3A due to a load. The workpiece W starts to be rotated at a proper speed suited to its diameter without being subjected to the reactional force from the rotary supporting stands 3, without being shifted in the rotating direction of the surface plates 1, 2, and being uniformly machined with the surface plates 1, 2 being brought into contact with its whole surface. |
