| 摘要 |
Device for precision measurement of the internal diameter of thin-walled pipes including a commercial three-point inside micrometer with one part-cylindrical shaped jaw segment connected to each of the three points of the micrometer and dimensioned so as to exhibit outer surfaces arranged in an ideal circle having a diameter equal to the nominal inside diameter of the pipe being measured. These three jaw segments are formed by radially slitting a cylindrical body having an outer circumference corresponding to an ideal circle having the diameter of the nominal internal diameter of a pipe to be measured. The slitting extends radially so as to form symmetrical 120 DEG circular arc portions for each jaw segment, with the small slits accommodating a retraction of the jaw segments to a slightly smaller diameter for insertion into the pipe, wherein they are expanded by the micrometer screw and associated feelers to conform to the inside of the pipe and to clampingly engage the inside of the pipe into an ideal circular arrangement. Preferred embodiments further include axial stop faces at the jaw segments, as well as jaw segments having a stepped configuration exhibiting a plurality of different nominal diameter outer surface configurations. |
