Extruder for production of wedge-shaped plastic plates has die head followed by adjustable rolls forming wedge shaped-gap and a cutter

摘要

The extruder has a die head(20) followed by a roll arrangement(30) comprising two rolls(32,34) with a gap between them. The gap has a thick section and a narrow section both formed by the distance between the outer surfaces of the rolls, the distance forming a thick section being larger than that forming the thin section. Alignment of the roll gap with the die head outlet, which has the same size and profile enables the extruded material to be rolled. A cutting system(40) behind the rolls cuts the rolled plastic into wedge-shaped plates. In one type of roll arrangement(30) the thick and thin sections of the gap are created at opposite ends of the rolls(32,34). Roll axes are at an angle to each other and when extended intersect each other. Rolls are adjustable to vary the angle between the axes. At least one roll may be cone-shaped. In a second type of roll arrangement the gap comprises two thick sections, one at each end and a thin section between them. The cutting system(40) cuts the rolled material transversely and along the narrow section. In a third type of roll arrangement the gap comprises two narrow sections, one at each end and a thicker section between them. In this case the cutter cuts transversely and along the central thicker section. In a further roll arrangement the gap comprises alternating thick and thin sections. In all cases rolls may have a textured surface.