Transmission device for use with differential pressure display, has annular gap that is provided between pole ring and cabinet so that reluctance force acts between magnetic poles of permanent magnet and pole ring

摘要

The device has a permanent magnet (4a) that is displaceable with respect to a cylindrical portion (3) of a cabinet (2). The magnetic poles (4N,4S) of the permanent magnet are made of soft magnetic material and a pole ring (5) is coupled to the permanent magnet by reluctance force generated by movement of the permanent magnet in the cabinet. An annular gap is provided between the pole ring and cabinet so that reluctance force acts between the magnetic poles and pole ring. An independent claim is included for differential pressure display.