PURPOSE: To make precise positioning stable, to make a static pressure X-Y table sufficiently rigid, and to enable the vibration of the static pressure X-Y table to be attenuated, by allowing a first and second sliding tables to engage with four parts comprising opposite slant surfaces and upper surfaces over grooves and providing the engaging surfaces with static pressure guides for supplying a static pressure fluid.

CONSTITUTION: The four surfaces comprising the opposite slant surfaces 10a, 10b of a trapezoidal groove of a bed 10 and the right and left upper surfaces 10c, 10d engage with the first sliding table 10 to guide it. The engaging sections are formed with static pressure pockets 20aW20d, and a static pressure supporting force is produced by a fluid passing through a pantagraph pipeline 11 and a pipeline 20 in the table 20. The first sliding table 20 is also formed with a trapezoidal groove, and similarly four surfaces engage with the second sliding table 32 to guide it. The engaging sections are formed with static pressure pockets 32aW32d so that a static pressure supporting force is produced between them and the engaging sections of the table 20. A lead screw 29 is rotatably driven via a reduction gear mechanism 25 by a motor 24 to feed the table 32.