GB1451469A - Flexible tubing - Google Patents

Abstract

1451469 Making flexible tubes ATCO RUBBER PRODUCTS INC 5 Nov 1973 [9 Nov 1972] 51290/73 Heading F2P A flexible tube consists of a helically wound strip R (Fig. 8) of polymeric material, the edges of the strip R being overlapped and fused to each other, and a helically coiled wire W which is sandwiched between the overlapping edges of the strip R. The tube is made by winding the strip R, which is produced by an extrusion head 32 (Fig. 2) and wire W onto a set of rollers 18a-l arranged in a generally cylindrical pattern, the rollers 18a-l being individually rotatably mounted and having peripheral grooves 24 therein, the rollers being skewed in their generally cylindrical pattern to cause the grooves 24 to collectively define a helical advance path for the. wire W. As described the rollers 18 are mounted, at one end, in self aligning bearings 44 in a fixed plate 20 and at the other end in self aligning bearings in an adjustable plate 38. The plate 38 is mounted on a central cylindrical member 80 by means of bolts 98 and slots 97 which allow the angular disposition of the plate 38 to be adjusted. This varies the skew of the rollers 18a-l and thus adjusts the pitch of the helical advance path defined by the grooves 24. The rollers 18a-l are driven in unison by an electric motor 54 via chain and sprocket devices 70, 72, 78. In use the extruded strip R is guided onto the rollers 18 by a roller 108 (Fig. 2) and the wire W is guided so that it lies on one edge of the strip R and engages the grooves 24. The edge of the next turn of strip R overlaps the wire W and previously laid edge to enclose the wire W as shown in Fig. 8 and the two edges are fused together by a pressure roller (not shown). Cooling air is directed to the interior of the tube as it is formed, via apertures in the central member 80, a conduit and a blower (not shown). As the tube is formed, it advances from the rollers 18 and is supported by rollers 102, 104 mounted between plate 38 and plate 100 on an extension 86 of member 80. Alternatively, especially when long lengths of tube are being produced, the formed tube may be supported by an air bearing conveyor (not shown). The apparatus also includes a cutting device 26 for cutting completed lengths of tubing.