PURPOSE: To enable the inner circumferential surface of a glass pipe or a pipe made of brittle material such as ceramics and the like to be well honed with no inner defect made such as cracks and the like.
CONSTITUTION: A hollow mandrel 1 is connected to an upper shaft 14, and is so supported as to be rotated and moved up and down. A wedge 4 which is formed into a parabolic surface 5 at its tip end, and can be moved up and down, is inserted in the inside of the mandrel 1. Both a guide 12 and a hole 3 in a slit shape are formed symmetrically with respect the axis at the tip end section of the mandrel 1, and both a honing stone 2 for polishing a glass pipe 8 and a polishing base 6 which joins and supports the honing stone, are inserted in the hole 3. The honing stone 2 is formed in a parabolic surface 5 at its opposite side, and a support section 7 which comes in point contact with the tip end inner surface of the mandrel 1, is formed at the lower end section of the polishing base.
Next Patent: POLISHING DEVICE FOR SEMICONDUCTOR WAFER AND MANUFACTURE THEREOF