GORODETSKY PNEUMATIC THREAD GAUGE MECHANISM

Compressed air is delivered from the measuring chamber of a back-pressure gauging system and passes along channel a of gauging plug 1 to radial orifices d and b. These orifices taper outward at their outer ends. Placed into these taper holes are steel balls 4 of a diameter close or equal to the most expedient diameter of the wires used in the three-wire method of measuring thread pitch diameters f…