Device for creating a region which is substantially free of magnetic field, surrounded by a region with a magnetic field gradient

摘要

A device for keeping electrical insulation joints in rails free of faults is described. These joints form a significant source of faults in rail-borne transport systems in which rail-borne train protection or train detection systems are arranged. The device has magnets for creating a substantially field-free region with a field gradient in all directions leading away from the region. This substantially field-free region is located at the insulating part of an electrical insulation joint. The field gradient ensures that magnetizable material always moves away from the field-free point.