| 摘要 |
PURPOSE:To eliminate the thermal deterioration of a melt and the disturbance of flow and to improve the thickness accuracy of each layer over the total width of a film by providing a control valve capable of controlling the gap between both end parts of the leading end parts of flow passages during molding operation and having a shape generating no stagnation of the melt and also providing a rod like body capable of altering the gap between the leading end parts of the flow passages to the flow passage of a central part. CONSTITUTION:All of the flow passages 107A, 107B, 107C processed to an insert body 107 are formed so as to have the same width and each of them is processed into a semicircular flow passage having a dimension slightly larger than the outer diameter of each of the control valves 112A-112D inserted in a composite adaptor in order to prevent stagnation. Meeting passages 107B'', 107C'' are respectively constituted by the wall surface of the insert hole of the composite adaptor and the wall surfaces 107B', 107C' of the flow passages of the insert body 107 and a part of the flow passage wall surface 5' of the composite adaptor opposed to the wall surfaces 107B', 107C' of the flow passages 107B'', 107C'' is formed by replaceable flow passage bodies (rod like bodies) 111A, 111B. The flow passage bodies 111A, 111B are formed from a round rod having the same outer diameter as each of the control valves 112A-112D. |
