To provide an inexpensive and highly reliable positioning apparatus for initializing a table even when any changeover sensor (field detector) different from a sensor for controlling positioning is excluded, concerning a positioning table apparatus comprising: a position detector for detecting the position of the table; a multi-phase motor; and a magnet preloaded hydrostatic bearing.
The apparatus comprises: the position detector for detecting the position of the table; the multi-phase motor for selectively changing-over a coil to be energized in response to the position of the table; an initialization driving current command setting part; a table speed arithmetic part, and a divider. The divider divides a signal from the initialization driving current command setting part by a signal from the table speed arithmetic part, adopts the arithmetic result as a command, and, then, drives a stage to the position of an original point switch.
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