PURPOSE: To locate a spindle rapidly by fitting a rollor in the root of a corrugation in an index device with the movement of a slide/to keep a lever at a predetermined position.

CONSTITUTION: When a spindle 2 stops its rotation, an index device 3 stops at a non-indexing position where a root 5 of corrugation stops in non-alignment with a pin 14. When a power cylinder is then operated to advance a slide 9, a lever 15 and rollor 17 thereon are also advanced so that the rollor 17 abuts against the corresponding slant surface of the corrugation 6 and fits the root 5 of the corrugation when the lever 15 pivotable about the pin 14 is a little slanted. Further, the lever 15 is located without inclination to locate the center of the roller 17 behind the center of the pin 14 with the advancing force of the slide 9 and finish the location of a spindle 2 at the indexing position.