PURPOSE: To express lost motion separately by an angle of play rotation due to the back gap of a transmitting element and a torsion spring constant due to elastic deformation, by processing measurements of torque of rotation and an angle of rotation.
CONSTITUTION: A measurement part 11 and a load device part 15 are coupled with a rotation transmitting device 1, rotation is fixed by a braking device 13, and a rotation driving device 7 is driven. An arithmetic device 16 obtains torque T and an angle θ of rotation detected by a rotation torque detector 9 and a rotation angle detector 10 at specific intervals of time and stores them in a storage part 16b, and an arithmetic part 16a performs linear approximation to three straight lines. Thus, three functions T are obtained as shown by equations 1W3. Then, θa and θb in the equations are found to find an angle B of rotation between those θa and θb by equation 4, and this is outputted by an output device 17 as an angle of play rotation due to a back gap between transmitting elements. The mean gradient K of gradients of equations 1 and 3 is found by equation 5 and outputted by the output device 17 as a torsion spring constant due to the elastic deformation of a transmitting element.
MIYAJI MASAHIRO
ISHIDA YASUHIKO
