Abstract: An actuator and programmable amplifier is operative for use with an expanding plug gage head operated by an axially movable plunger having a tapered operating end and an opposite cross head end. The cross head end of the plunger is releasably received and secured through a slot in a retracting lever which is pivotably mounted in the actuator/amplifier housing. A compression spring normally urges the plunger to a fully extended position within the gage head. The retracting lever is actuatable for withdrawing the plunger from the gage head. The actuator/amplifier device includes a transducer having a core which is coupled to the crosshead end of the plunger. The transducer is operative for measuring an axial position of the plunger within the gage head. The programmable amplifier includes a memory for storing a plurality of sets of configuration data for a plurality of different gage heads.

Abstract: There is disclosed in the present application, a ring gage assembly comprising two interdigitated measuring elements slidably mounted and urged toward each other to embrace an external, generally cylindrical surface of a workpiece to provide a precise measurement of the dimension of the surface. For this purpose, the ring gage assembly is detachably mounted on a known amplifier/indicator device which includes mechanical amplification of the expansion and contraction of the ring gage and an indicator upon which there is shown by a pointer any deviation from the basic size of the dimension being measured at any given time by the ring gage. The ring gage assembly is coupled to the amplifier/indicator by a tapered plunger which enters a split socket in the measuring elements and, by being pressed into the socket, causes measuring surfaces of the two elements to approach each other and cooperates with the amplifier in magnifying pointer motion at the indicator for a given expansion or contraction of the ring gage.