PURPOSE: To prevent malfunction by inserting two guide pins into a template for confirming the hole position in the row and the column direction, and controlling to drive an NC multiple spindle drilling machine according to the signal from a sensor to detect the inserting condition.

CONSTITUTION: A column direction confirming plate 10 is arranged parallel to a bed 1 on a loading table 9 on the floor on one side of the bed 1. A row direction confirming plate 11 is fitted on the side of the body 1 of a column 2 in the direction normal to the column direction confirming plate 10. These direction confirming plates 10, 11 are provided with holes which are fitted to the recessed hole group. And the column 2 is provided with guide pins 14, 20 which can be elevated by means of cylinders 13, 19, and these guide pins are inserted into/released from the holes of both direction confirming plates 10,11. Boring operation is achieved when the guide pins are inserted into and the lower end limit switches 17, 23 get actuated. When the guide pins 14, 20 are withdrawn and the upper end limit switches 16, 22 get actuated, they are shifted to the next hole position.