A measurement instrument in the form of a plug gage comprises a tubular body within which there is centered an axially movable rod, one end of which is intended to transmit the axial movements of said rod to a transducer system connected to the tubular body, while the other end thereof bears a conical part coaxial with said rod, with the lateral surfaces of the conical part resting against radially movable feeler balls, each of which is housed in a guide channel transverse to the longitudinal axis of the tubular body. The plug gage is characterized in that the tubular body bears over at least a portion of its length a coaxial centering sleeve which is removable and interchangeable, this sleeve being provided with transverse openings intended to permit the passage of the balls.
The inventive device (FIG. 1) comprises a hollow head 14 accommodating a resilient bush 22 having a slider 26 which is axially adjustable by means of an adjusting screw 30. Said bush is slotted to give radial leaf springs which co-operate with balls 36 held in recesses provided in hollow head 14 so as to be maintained in spring engagement with a slot 38 provided within a sleeve 16, which slideably accommodates said head 14 and removably holds caliper gauge D. When the latter becomes accidentally jammed in pipe A, operative connection between hollow head 14 and said sleeve 16 is cut off and said head is conveniently allowed to move forward and then quickly backward to bump against the jammed caliper gauge and knock it out of the pipe.
The gage assembly of the present application includes a gage head detachably mountable on an amplifying and indicating mechanism for providing a graduated indication of any deviation in the size of an internal enlargement or groove in a bore in a workpiece. The gage head includes a pair of opposed radially slidable blades urged outwardly by a spring force exerted on a tapered plunger by a spring forming a part of the amplifying and indicating mechanism. The outward extension of the blades, which are sized and shaped to enter the groove in the workpiece, is coupled to the amplifying and indicating mechanism by the axial displacement of the plunger and displayed on an indicator dial forming a part of the mechanism. The gage head is centralized in the bore by a pilot adjacent the blades, which aligns the head with the axis of the bore.
In a dimensioning head for a plug gage, a pair of exteriorly projecting balls project through openings on either side of the longitudinal axis of the housing for contacting the inside diameter of the bore hole to be measured. Each of the balls contact a V-shaped groove of a guide surface to the housing to ensure accuracy and repeatability of measurements.
In a dimensioning head for a plug gage, a pair of exteriorly projecting balls project through openings on either side of the longitudinal axis of the housing for contacting the inside diameter of the bore hole to be measured. Each of the balls contact a V-shaped groove of a guide surface to the housing to ensure accuracy and repeatability of measurements.
A tool for checking the required spacing between adjacent fingers of the spud in a control rod drive. The tool is a GO-NO-GO gauge with tight tolerance. The spud finger gauge has two circular cylindrical pins of different diameter. One pin (i.e., the GO pin) has a diameter less than the required spacing between adjacent fingers of the spud. The other pin (i.e., the NO GO pin) has a diameter greater than the required spacing between adjacent fingers of the spud. The spacing is correct if the GO pin passes through the spacing and the NO GO pin does not.
