SHAPE MEASURING INSTRUMENT

PURPOSE:To measure the sectional shape of the vane of a turbine runner efficiently by fitting a travel rail nearby the vane, providing a moving carriage which can be positioned on the rail and mounting a displacement sensor and a printer on the carriage. CONSTITUTION:An NC controller 7 operates a positioning driving mechanism 8 according to a positioning command value which is inputted previously and operates the laser type displacement sensor 11 which is mounted on the moving table 10 on the travel rail 5 to respective measurement positions. The sensor 11 measures the interval between the rail 5 and vane 4. Its measured value is sent to an arithmetic processor 13 and arithmetic processing is performed by using arc radius value data and center position data on the rail 5 which are inputted in advance to find the sectional shape value at each point of the vane 4. Further, the value of deviation between the previously inputted measured value and sectional designed value data is found and printed on an ink jet printer 12 as cutting size or extra-banking size nearby the measurement point on the vane 4. Above operations are performed continuously as to one section.