Abstract: A reinforced bobbin which when wound with a sensing winding forms the armature of a D'Arsonval movement measuring instrument. The reinforced bobbin consists of a thin elongated open rectangular bobbin with detent holes centered along the axis of revolution of the bobbin in the measuring instrument. A nonmagnetic low density ball with a diameter slightly larger than the opening in the bobbin is locked in position inside the bobbin by the detent holes to prevent inward deformation of the bobbin when the measuring instrument is subject to rough handling.

Abstract: A compact and symmetrically arranged construction for electrical current indicating meters of small size. The meter construction comprises a concentrically pivoted coil which encircles a rounded magnetic fluxplate.

Abstract: A compact and symmetrically arranged construction for electrical current indicating meters of small size. The novel construction for a meter comprises a unitary frame member combined with concentrically arranged components.

Abstract: Adjustment of an electrical measuring instrument of the D'Arsonval type is achieved by rotation of an annular leaf spring contact mounted to rotate between an annular plate and a flanged eyelet extending through the plate and leaf spring. A conducting coil spring attached to the spring contact transmits rotary orientation of the spring contact to an armature assembly disposed for rotation against the return force of the coil spring in an magnetic field.

Abstract: Adjustment of the zero point of an instrument is achieved by rotation of a rotary element extending through the casing of the instrument. The rotary motion of the rotary element is translated into a lateral motion of an intermediate adjustment element. The lateral motion is a side to side motion within the instrument relative to the sides of the instrument casing. The lateral motion of the intermediate element is in turn translated into a pivot motion of a suspension element of the instrument. The pivoting of the suspension element causes deflection and adjustment of the indicating element of the instrument from which readings of the instrument mechanism are taken.