Long-scale meter movement having a one-piece outer pole and return ring, and a demountable subassembly therein comprising magnet, central core, moving coil and support frame

A long-scale meter movement of the moving coil type in which one leg of the coil operates within an annular magnetic gap between concentric pole faces and another leg of the coil extends through a central passage in the inner core piece, comprising a block magnet, an outer ring member having an outer pole piece and a return ring portion in a unitary generally circular configuration, the return ring portion having an inner surface in contact with one pole of the magnet, a central core having a central passage, an access slot, and a surface in contact with the other pole of the magnet, a one-piece frame having front and rear supports for the coil and connecting portions extending through the return ring region of the outer ring member alongside the magnet, a pair of core supports extending through the frame in interlocking relation therewith at the front and rear of the magnet, the portions of the core supports extending through the frame having notches in their side margins which interlock with portions of the frame close to the magnet, the core ends having circular shoulders coaxial with the axis of said central passage, the lower ends of the core supports having circular apertures within which the circular shoulders are received, and the core supports having access slots aligned with the access slot in the core.