摘要 |
<p>A method for positioning a tool (3) mounted on a spindle (2) of a numerical control machine tool in the visual field (20) of a visual system (7) for measuring the tool, includes a step of moving (35) the rotating spindle along an axis (Z) from a reference position (Z0) towards a target position (Zobj) defined in the visual field, and a step of acquiring images of the visual field. The stop of the spindle movement along the axis is controlled as soon as an acquired image (IM1) reveals (36) that a determined portion (13) of the tool, for instance a tip, has entered the visual field. When the stop is controlled (37), an instant position (Z1) of the spindle is acquired (38) and a distance (POS) between the tip of the tool and the target position is measured (39). On the basis of such instant position and distance, a final position (Z2) is calculated (40), and the spindle is brought (42) to such final position. A preliminary step (31) during which the spindle and the tool are displaced of a certain amount towards the visual system, and/or a phase of fine positioning (44, 45, 46, 42) can be considered. A machine tool includes control units (4, 10) that implement the method for positioning.</p> |