GB1418542A - Manufacture of convoluted tubing and bellows - Google Patents

Abstract

1418542 Corrugating tubes UNITED FLEXIBLE METALLIC TUBING CO Ltd 29 Aug 1974 [12 June 1973] 28025/73 Heading B3E Apparatus for corrugating tubing 1 comprises an arbor 5 having a free end mounting at least one roller 7, 8 for engaging inside the tube, and a mandrel 6 carrying the tubing and having a free end opposite that of the mandrel, wherein a chuck 14 is provided to rotate the tubing relative to the mandrel, and a support is provided at the free end of the mandrel offset from its axis and on the axis of the rollers, which detachably engages the free end of the arbor. Bending moments on the arbor are thus relieved. The mandrel and arbor may rotate, the tube being stationary, or as in Fig. 1, the arbor is held stationary on a tailstock 3 while the tube and chuck 14 are rotated in a headstock 2 through which the non-rotary mandrel 6 passes. The arbor 5 is slightly pivotable at the tailstock by a fluid pressure jack 48, and movable axially by jack 44. The whole tailstock can be pivoted with the arbor. The mandrel is movable axially in either direction by jack 32 through a lost motion connection 36, 38, 39, and can be urged towards the arbor by jack 31. The two rolls 7, 8, Fig. 2, are mounted on a shaft 49 located in the end of arbor 5 by a pin and slot coupling 50 and urged apart by spring 53. A head 51 on the shaft is engageable in a recess 52 in a plug 18 on the end of the mandrel. A sleeve 20 is located on the plug opposite chuck 14, the jaws of which are shaped to engage a partially corrugated tube 1, and which is releasable manually but engages itself automatically. The outer roller 9 on fixed shaft 57 is of snail cam shape, and has a cut out to clear the tube 1. In operation, the arbor and mandrel are disengaged by jack 32, and the arbor and tailstock are swung aside to allow a partially corrugated tube to be fed on to the mandrel, chuck 14 being manually held released. The chuck is then allowed to grip the tube on to sleeve 20. The arbor and mandrel are then swung back, and engaged by jack 32. The tube is rotated by chuck 14, and roller 9 turned by hand so that it engages the tube, whereafter it is driven by the tube, and forms a deepening corrugation in the tube. The two rollers 7 and 8 are moved towards each other meanwhile by jacks 44 and 31. Roller 9 stops when the cut out reaches the tube, then the arbor can be pivoted by jack 48 to clear the corrugation, so that the tube can be inclined forward for the next corrugation to be formed similarly. In the embodiment of Fig. 4, the tailstock 62, arbor 65 and inner rollers 67 are similar, but there are two outer rollers 72, 73 mounted on coaxial shafts 74, 75 on a cross-slide 69 movable tranversely to the axis of tube 60 by a cam drive 70. The required axial movement of roller 72 as it is moved radially to form a corrugation is obtained by lever 79 pivoted on slide 69, bearing on a fixed incline 81 at elbow 80 and bearing at its free end on a cap 82 to move the roller shaft 74 against spring 78.