| 摘要 |
<p>PURPOSE:To judge accurately and automatically the finish-point of discharging melted polymer from a tank by detecting the pressure change of gas adjacent to the exit port for melted polymer in a polymerization tank of a circulating separation type. CONSTITUTION:For instance, melted polymer in a polymerization tank 1 is discharged onto a cooling drum 6 in a sheet shape from an exit valve 2 and exit port 3 by pressurized inert gas, and then the polymer sheet is cooled and solidified by cooling water from a shower 5, and is cut after being transferred through a cooling tank 7. In such a process, the pressure adjacent to the exit port 3 is led to a pressure-sensor 10 by a small pipe 9 having a fine pipe 3 for receiving pressure, when the melted polymer in a polymerization tank has been decreased and pressurized gas has leaked from the exit port 3. Then the change of resistance valve caused by piezo redistance-effect of a pressure sensitive semiconductor device is applied, and the relational operation is carried out between observed value amplified in a logical circuit which converts pressure to electric energy and the predetermined valve. Consequently, the exit value 2 is automatically closed by the signal being sent as the contact input.</p> |
