Patent ID: 6640743
Filing Date: 2003-11-04
Classification: G01D,Y10S

Abstract:
A meter comprising:a scale plate; a wiring board disposed behind the scale plate in parallel to the scale plate; a pointer disposed in front of the scale plate; a plurality of light sources, disposed on a front surface of the wiring board, for illuminating the pointer; a driving unit, fixed to a rear surface of the wiring board, for driving the pointer, the driving unit including a stepping motor composed of a pair of coil units having terminal pins for supplying electric power to the coil units and a magnet rotor adapted to be rotated by energizing the pair of coil units; and a pointer shaft connected between the pointer and the driving unit through the scale plate and the wiring board, wherein: the plurality of light sources are positioned around the pointer shaft in the vicinity thereof and electrically connected to the wiring board; the terminal pins are positioned remote from the pointer shaft and electrically connected to the wiring board; the pair of coil units are positioned symmetrically with respect to a line extending through the pointer shaft and a center of the magnet rotor so that longitudinal axes of the pair of coil units cross each other substantially at the center of the magnet rotor; and each of the pair of coil units includes a bobbin around which a coil is wound, the bobbin having a pair of flanges formed at both longitudinal ends thereof, each flange extending perpendicularly to the longitudinal direction of the bobbin and having one end more remote from the pointer shaft and the other end closer to the pointer shaft; the terminal pins are connected to each flange at the more remote end and electrically connected to the wiring board at a position corresponding to the more remote end; and the driving unit further includes a reduction gear train connected between the magnet rotor and the pointer shaft, so that the pointer shaft is driven by the magnet rotor through the reduction gear train with a reduced rotational speed.