Device for producing flexible plastic hose - with large diameter ribs

摘要

Device for producing a flexible plastic tube with transvere grooves consists of an extruder with an annular nozzle and two mould havlves, each witha semi-tubular cavity with a ribbed profile. They can move along tracks so that two halves facing each other will form a hollow mould. Hydraulic devices press in a rib profile when a plastic hose is present in the moulds. Each half has a heated semi-circular extension of such length that, in the end operative position of the mould halves, the annular nozzle of the extruder is inside the heated semi-cicrular parts. The drives for controlling the extrusion speed, separating the mould halves, and the devices for returning them to their starting point and for the device limiting the mould halves are so adjusted to one another that at the start of a cycle the last formed transverse groove can work in conjunction with the last rib profile lying on the mould halves at the end facing the extrusion nozzle. Means for inserting a plastic tube into the rib profile of the mould halves consist of (i) a tube inflation device that can move over a support bar connected to the core within the operating track (ii) the two expanding sealing discs and (iii) a medium outlet between them connected to a continuous bore in the core, (iv). Adjustable pressure controls remove the medium from the outlet after expanding the sealing discs for forming an enclosed space. (v) Devices limit the movement of the tube inflator and (vi) return the latter from the end to the starting position after cancellation of the expansion of the discs. There is (vii) a connection between the space between the core and the tube inflator and the environment.