FIELD: measurement technology, methods of measurement of width and deviation of position of key slot with regard to axis of hole. SUBSTANCE: measurement object 4 is based in case 3 by its setting with hole on centering pins 1 and 2 with provision of contact of measurement prod 5 to side surface 7 of tested key slot. Relative angular position of measurement object 4 and case 3 is set true by way of recurring-turning motions of measurement object 4 on centering pins 1 and 2 and measurement prod 5 with rod 6 around axis of above-mentioned rod. Recurring-turning motions of measurement prod 5 are carried out in plane parallel to longitudinal axes of centering pins 1 and 3. Invariability of readings of counting head 8 during above-mentioned motions of measurement prod 5 is achieved by adjustment. First reading is taken. Measurement prod 5 is brought in contact with another side surface 9 of tested key slot and then in turn with extreme points г and д of hole of measurement object 7 taking at same time second, third and fourth readings of counting head 8. Width of key slot is determined by difference of first two readings and with due account of diameter of measurement prod 5, deviation from symmetry is found by half-difference of two scopes computed by differences of first and fourth, second and third readings. EFFECT: increased measurement precision. 2 dwg
