| 摘要 |
PURPOSE:To enable labor to be reduced extremely by improving an operation rate by a method wherein a characteristic of a sheet is enabled be controlled at a specific value precisely by providing a control system which controls a stretching degree of a high polymer by feeding back a measured result of an on line double refraction measuring instrument to a stretching mechanism. CONSTITUTION:Measured outputs of a first on line double refractometer 16 measuring double refraction of a sheet coming out from a vertical stretcher 5 and a second on line double refractometer 17 measuring double refraction of the sheet coming out from a horizontal stretcher 11, are inputted to a data processor 22 as a digital data via respective amplifiers 18, 19 and A/D converters 20, 21, and processed by arithmetical induction or the like of a retardation value, a main refraction rate direction, etc. Then, the on line double refractometers 16, 17 are incorporated in a production line of a high polymer sheet thus, and a double refraction characteristic of the sheet in traveling is measured on line. The result is fed back to the vertical and horizontal stretchers 5, 11 and stretching control is carried out on line. |
