| 摘要 |
A positioning apparatus includes a machine bench 1, an external pressure linear bearing assembly 2 and a slide body 3 mounted on the machine bench 1 through the bearing assembly 2 for reciprocating movement relative to the machine bench. The positioning apparatus has a frictional reciprocating drive mechanism 4 for reciprocatingly driving the slide body 3 which is provided and includes a main shaft 5 adapted to be rotated, and a plurality of rollers 9 disposed around the main shaft 5 and inclined at a predetermined angle relative to the main shaft 5. Each roller 9 is pressed relative to the main shaft 5 by a pressing member 15. The slide 3 and a rail 20 are made of ceramics. Magnets 41 are provided on the slide body 3 for developing forces of magnetic attraction between magnetizable members 42, provided on the machine bench 1, and the slide body 3. |
