| 摘要 |
PURPOSE:To surely and highly accurately detect the abnormality of generated magnetic flux during molding process and consequently improve the magnetic characteristics of a molded item by a method wherein the generation of the abnormality in magnetic field is detected by monitoring whether the integrated value of the magnetic flux lies within the predetermined range or not. CONSTITUTION:Because generated magnetic flux passes through the bars 16, the magnetic flux is measured with a search coil 32 and fluxmeter 34. Simultaneously with the start of energizing to magnetic field generating coils 28 and 30, an actuation start signal 37 is inputted to an integral time setter 38, which starts the time counting with the simultaneous actuation of an integrator. The integrated value at the time when the time counting of the integral time setter 38 comes to an end is inputted to a comparator 40, which compares said integrated value with the upper limit value and lower limit value set in an upper and lower limit value setter 42. When the integrated value falls out of the range between the upper limit value and the lower limit value, an alarm signal 44 is outputted so as to actuate, for example, an abnormality alarm device. Thus, the molding of a molded item, the magnetic characteristics of which runs out of the predetermined magnetic characteristics, is prevented being done continuously. |
