the feeler varying the impedance in a circuit

Control systems or devices for copying directly from a pattern or a master model; Devices for use in copying manually > using a feeler or the like travelling along the outline of the pattern, model or drawing; Feelers, patterns, or models therefor > Means for transforming movement of the feeler or the like into feed movement of tool or work > involving electrical means > using mechanical sensing > the feeler varying the impedance in a circuit

Control systems or devices for copying directly from a pattern or a master model; Devices for use in copying manually > using a feeler or the like travelling along the outline of the pattern, model or drawing; Feelers, patterns, or models therefor > Means for transforming movement of the feeler or the like into feed movement of tool or work > involving electrical means (program recording for copying purposes in a separate apparatus G05, G11) > using mechanical sensing > the feeler varying the impedance in a circuit