| 摘要 |
PURPOSE:To accurately detect the bank in a chamber, by mounting one or more pair of photodetectors to both side walls of a chamber, which is provided along an extrusion roll to temporarily store an extrudate, in opposed relation to each other. CONSTITUTION:Press plates 25 are additionally provided to the outer side surfaces of chamber side plates 11 and a light projector 20a, a photodetector 21b and a light projector 22a are successively arranged outside one of said press plates 25 from above at the positions opposed to transparent windows 13 and circular holes 25a while the light projector and the photodetector are arranged on the side of the other chamber side plate 11 in a replaced state. The raw rubber 7 sent in a chamber 3 from the center of the peripheral surface of the extrusion roll 2 goes toward the bottom part of the circular arc surface of a chamber block without blocking the lights of the photodetectors to be successively stored in the chamber but, when a bank amount increases, the uppermost part at the center of a bank 30 successively blocks light from an upper stage to a lower stage and, when said bank amount decreases, light successively passes from the upper stage to the lower stage. Therefore, the bank amount can be properly detected over four stages by three pairs, i.e. of upper, middle and lower photodetectors. |
