System, method, and apparatus for detecting fasteners during automated re-work of defective workpieces

A method of locating and removing screws from a disk drive spindle for enabling an automated rework process for disk drive spindles, the method comprising:

• (a) providing a disk drive spindle having a plurality of screws secured thereto in a symmetrical configuration;
• (b) positioning a sensor adjacent the disk drive spindle;
• (c) moving one of the disk drive spindle and the sensor relative to the other such that the sensor scans the disk drive spindle for the screws;
• (d) detecting a location of each of the screws with the sensor;
• (e) providing signals that precisely identify the locations of the screws;
• and then
• (f) orienting an automated screw driver relative to the screws and removing the screws from the disk drive spindle with the automated screw driver.

A system for locating and removing screws on a disk drive spindle having a plurality of screws mounted thereto for enabling an automated rework process on spindle assemblies, the system comprising:

• a capacitance probe for detecting the screws on the disk drive spindle;
• a fixture for positioning the capacitance probe adjacent the disk drive spindle;
• a step motor for rotating the capacitance probe relative to the disk drive spindle such that the capacitance probe scans the disk drive spindle for the screws, detects an angular location of each screw relative to the disk drive spindle, and provides signals that precisely identify the locations of the screws;
• an automated screw driver responsive to the signals from the capacitance probe for engaging and removing the screws from the disk drive spindle;
• and
• a controller for controlling the capacitance probe, the fixture, the step motor, and the automated screw driver.