Eddy-current coupled magnetic speedometer movement for vehicle

摘要

The eddy-current coupled magnetic speedometer movement for a vehicle has a central spindle (1) carrying a pointer (2) and a helical restoring spring (3) which is attached at its inner end to the spindle (1) and has an outermost coil which fits into a clock-type barrel (not shown) and is located at its extremity (4) by a fixed stop (5). The spring winding direction is such that as the pointer (2) moves clockwise to indicate increasing speed the spring (3) is caused to unwind to avoid any frictional contact between coils and consequent loss of accuracy.