System which removes swarf from holes bored in ferromagnetic pieces - using AC magnetic field to agitate swarf and DC field to attract it

摘要

The swarf-removing system consists of a magnetisable pin or rod (15) inserted into the hole and magnetised to attract swarf in the hole to it. The pin or rod is then removed from the hole bringing the swarf with it. Whilst the pin or rod is being inserted into the hole, an ac magnetic field is generated in the region of the hole by passing an alternating current through a coil (16). This ac field causes the swarf particles in the hole to vibrate such that they are picked up by the pin or rod more readily and are less likely to drop off as the pin or rod is withdrawn from the hole. The amount of swarf left in the hole after the pin or rod has been withdrawn is therefore greatly reduced.