Mitsubishi Jukogyo Kabushiki Kaisha

Yuso Matsunaga

Hirofumi Yoshikawa

Masaki Nishioka

Hironari Okitomo

Kensuke Ide

In a profiling method constructed so that NC working is performed on the basis of profile locus data obtained by profiling a shape of a model by a profiling machine, a digitized method of the profile locus is characterized in that position data of the model surface, obtained by adding a position of the profiling machine and a displacement signal from a tracer head at each sampling time, are rounded through a low-pass filter upon a profiling operation, and a time constant of the filter is automatically changed in response to the rate of change of the shape of the model. According to this method, fluctuation of the profiling machine, which can not be corrected by the filter heretofore and is an error as it is, is corrected, and a stylus displacement signal, delayed as compared with a response of a profiling machine position signal upon high speed profiling operation, is greatly improved so that high speed profiling operation can be attained.

Method of digitizing a profile locus

An improved profiling control apparatus controls a profiling machine so that the apparatus judges whether an exact profiling operation is performed by the machine at a place where a surface shape of the model to be profiled is suddenly changed, for example at a step, without jumping of a stylus from the model surface, and the profiling machine performs the exact profiling operation without jumping of the stylus. The profiling control apparatus, which detects a displacement of the stylus pressed on the model surface from a tracer head and controls the profiling machine in accordance with the displacement detection signal, includes a displacement compounding unit for compounding three dimensional displacement signal .epsilon.x, .epsilon.y and .epsilon.z to produce a displacement signal .epsilon.(=.sqroot..epsilon.x.sup.2 +.epsilon.y.sup.2 +.epsilon.z.sup.2), a displacement differentiating unit for differentiating the displacement signal to produce a differentiated value d.sup.2 .epsilon./dt.sup.2, a comparison voltage producing unit for producing a comparison voltage Vc corresponding to a maximum acceleration .beta.max of the pressed stylus which can be produced thereon, and a comparison unit for comparing the comparison voltage Vc with the differentiated value d.sup.2 .epsilon./dt.sup.2 to produce a jumping detection signal when d.sup.2 .epsilon./dt.sup.2 =Vc. The profiling control unit is particularly suitable for profiling the model surface of which a shape is suddenly changed.

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Hiroshima, Japan

Yuso Matsunaga