APPARAT FOR YTUNDERSOKNING MEDELST EN SOND AV ETT SFERISKT FOREMAL

摘要

Apparatus for detecting surface flaws in generally spherical articles such as bearing balls. A spindle carrying a vacuum chuck at one end for gripping the ball is driven to rotate the ball about a first axis. An eddy current probe mounted for rotation about a second axis generally orthogonal to the first axis is urged against the ball to scan a circular strip for cracks and is rotated about the second axis to vary the location of the strip being scanned along the first axis. The probe output is applied through a bandpass filter to a threshold alarm and to the vertical input of an oscilloscope triggered synchronously with the rotation of the spindle.