Patent GB-969570-A (GB)
Title: Improvements in tube cutting machines
IPC: B23D21/00
Filed: 1963-08-31
Abstract: 969,570. Sawing; cutting tubes. TEXTILE PAPER TUBE CO. Ltd. (Sonoco Products Co.). Aug. 31, 1963, No. 34500/63. Headings B4B and B5L. Apparatus for cutting tubes into lengths comprises two parallel rollers B, D, Figs. 1 and 6, lying in substantially the same horizontal plane to support a tube T, means for rotating one of the rollers to rotate the tube about its axis, a rotatable clamping roller G carried on a pivoted arm H movable to bring the roller into engagement with the upper surface of the tube, and a rotatable cutting device M, such as a circular knife or saw, carried on an arm 156 movable to cause the device to move a distance equal to the thickness of the wall of the tube to be cut. The front roller B is in two parts and has its outer ends mounted in bearings 10, Fig. 4, on the frame A of the apparatus and its inner ends mounted in bearings 14, the space between the parts permitting the cutting device, which, as described, is a saw, to pass to the tube to be cut. The left-hand part of the roller extends beyond the bearing 14 to provide support for the tube, which may be flexible, in the vicinity of the cut. The outer ends of the parts of the roller are provided with sprockets 16 connected by chains 30 to a shaft 24 chaindriven by a motor 18. The rear roller D is mounted in blocks 32, 33 adjustable laterally of the axis of the roller by screw-and-nut arrangements 60, 62 and hand wheels 64 on carriages 34, 35 whereby the roller is adjustable to a position parallel to the front roller. The carriages 34, 35 are movable along transverse shafts 36, 37 by screwshafts which extend parallel to the shafts 36, 37 and are interconnected by bevel gearing 44, 45 and a shaft 46 whereby when the right-hand screw-shaft is rotated by a handle 48, both carriages move to vary the spacing between the front and rear rollers B, D, a scale 54 and indicia 52 permitting the rear roller to be set according to the size of the tube to be cut. The clamping roller G is rotatably carried in bearings 66 at the upper ends of arms H, Figs. 4 and 6, fixed to a shaft 72 rotatable in bearings 74 on the frame. A lever 76 is secured to the shaft 72 and is movable by a pneumatic device 80 to rock the shaft and swing the arms H so that the clamping roller is moved into or out of engagement with the tube. The configuration of the arm is such that, irrespective of the size of the tube, the roller G always engages the top surface of the tube. A pair of collars 88 are also fixed to the shaft 72 and are connected by chains 90 to levers 94 which, at one end, are pivoted to the frame and, at the other end, carry wheels 96 with their axes transverse to the axis of the tube. When the shaft 72 is rocked by the device 80 to raise the clamping roller G, the levers 94 are also raised so that the wheels 96 engage and lift the tube from the front and rear rollers to enable it to be moved endwise to a cutting position. The levers also carry cylindrical rollers 102 which are below the front and rear rollers when the latter is positioned for small diameter tubes but support a large diameter tube when the rear roller is adjusted to its rearward position. The tube is movable on the wheels 96 or rollers 102 to a cutting position determined by a stop K which is secured to a rail 108 which is formed with a rack engaged by a pinion rotatable by a hand wheel 140 whereby the position of stop is adjusted. A pointed screw 142 can be rotated by a hand wheel 144 to engage and lock the rack in its adjusted position. The saw M is mounted in bearings at one end of a double-armed lever 156, Fig. 6, which is rockable about a pivot 158 by a pneumatic motor 166, the saw being rotated by a belt drive from a motor having the axis of its driving pulley coaxial with the pivot 158 so that rocking of the lever does not affect the tension of the belt drive. In operation, a tube is placed on the front and rear rollers B, D with the clamping roller G in its raised position, the wheels 96 or rollers 102 also being in their raised position. The rear roller is then adjusted to the diameter of the tube and the tube moved on the wheels 96 or rollers 102 to a position abutting the stop K. The motor 18 is then operated to rotate the front roller and thereby the tube, and the saw is advanced by actuation of the pneumatic motor 166. In another embodiment for cutting tube of smaller diameter, the front and rear rollers B<SP>1</SP>, D<SP>1</SP>, Fig. 12 are mounted in bearings 204, 210 fixed to a frame 19<SP>1</SP>, and the rear roller is in two parts and has a reduced diameter portion to permit the passage of the saw M<SP>1</SP> and accommodate part of the driving pulley so that the saw can engage the tube. The clamping roller G<SP>1</SP> is mounted in a counterbalanced framework H which may carry switches 224 controlling a motor connected by a chain to the front roller B<SP>1</SP>, and a pneumatic motor 260 for rocking a lever 256 carrying the saw M<SP>1</SP> about a pivot 258, the saw being driven from a motor having its axis coaxial with that of the pivot. The stop K<SP>1</SP> is adjustable in a manner similar to that described in the preceding embodiment but is formed with a portion 242 extending between the front and rear rollers to enable a small diameter tube to engage the stop.