Linear motor disc rotor - is constructed with stiffening webs or slots to compensate for differential thermal expansion

摘要

A motor uses at least one linear motor section to impart motion to a rotor in the form of a disc. The losses generated in those parts of the disc moving at an angle to the travelling field can generate sufficient heat to distort the disc causing rubbing in the air gap and damage to both rotor and armature. To minimise the distortion the rotor, which is made of a solid disc, may be either stiffened or slotted locally to give expansion gaps. The stiffening may take the form of a flanged rim, dished centre, radial ridges or a combination of these. The slotting may be circumferential, radial or a combination or, alternatively, it may consist of a large number of perforations. Air or liquid cooling may be used in the machine.