Method of diagnosing pressing machine based on detected physical value

Abstract

A diagnostic method of diagnosing a press for the presence of any abnormality that deteriorates a quality of a product manufactured by the press, wherein physical value (Fs, Fsi, Ff, Ffi, Fp, Fpi, Xsi, Xei, Xy, Xz, Vx, Gx, Gy, Gz, Temp A, Temp B, Va0, Vf0, Vd0, V, Aa, Ag, Az, Afi, Ps, Pmai, Psa, Paa, Pyai, Peai, Pzai) such as a load generated at a selected portion of the press during operation of the press is detected, and the press is diagnosed for any abnormality, on the basis of the detected physical value, and according to a predetermined reference. For example, the diagnosis is effected based on: a waveform of a load detected in relation to a physical value which changes during a pressing cycle; a distribution of local values of the load detected local portions of the press; a correlation between the load and the physical value; a patter of variation of the load as the number of pressing cycles; a displacement amount, velocity or acceleration, or a temperature of a selected component of the press; or a capacity of a fluid used for a cylinder which produces a load or force.