FIELD: measurement technology, size test of parameters of key slots in shafts. SUBSTANCE: shaft is based with cylindrical surface in prism ensuring contact of lug with mentioned surface. Reading unit is set to zero. Shaft is turned around axis of cylindrical surface so that measurement lug enters tested slot and contacts slot bottom at start of slot. Then shaft is given reciprocating motion to achieve perpendicularity of axis of reading unit with regard to bottom of tested slot, first reading of mentioned unit being depth of tested slot is recorded. Turning and moving rod with feeler gauge one achieves alternate touching of side surfaces of tested slot with side barrel-shaped surfaces of feeler gauge, primary readings of indicator being fixed. Alternate touching of barrel- shaped surfaces of feeler gauge with measurement plane is achieved by turning and moving rod and starting readings of indicator are fixed. Deviation of symmetry and width of tested slot are found by mentioned primary and starting readings of indicator. Shaft is reset in prism to ensure contact between measurement lug and bottom of tested slot at its finish, reciprocating motions of shaft are repeated with achievement of perpendicularity of reading unit to bottom of tested slot, second reading of reading unit is recorded, deviation from parallelism of bottom of tested slot with reference to axis of cylindrical surface is found by difference of first and second readings of mentioned unit. Rod with feeler gauge is turned and moved to achieve touching of side surface of tested slot with barrel-shaped surface of feeler gauge, secondary reading of indicator being recorded. Difference of secondary and primary readings of indicator obtained by touching of one and same side surface of slot with one and same side barrel-shaped surface of feeler gauge determines value of skewness of tested slot. EFFECT: enhanced productivity of test thanks to reduction of number of operations. 2 dwg
