Patent GB-1184841-A (GB)
Title: Pipe Cutoff Apparatus and Method
Inventor: DAVIS PAUL KNIGHT
IPC: B23D45/18
Filed: 1968-02-05
Abstract: 1,184,841. Dividing by fusion. PACIFIC ROLLER DIE CO. Inc. 5 Feb., 1968, No. 5760/68. Heading B3V. [Also in Division B5] Apparatus for cutting an elongated sheet metal pipe 9 moving at a predetermined rate along a path extending longitudinally of the pipe and rotating about its axis comprises a carriage 16 supported for movement parallel to the path and driven at the same predetermined speed by driving means 12, cutting means 20, such as a saw blade or torch, carried by the carriage for movement transverse to the path into and out of cutting relation to the wall of the path, and means responsive to the movement of the carriage past a first point for moving the cutting means into cutting relation for at least one complete revolution of the pipe and past a second point spaced from the first point a fixed distance for moving the cutting means out of cutting relation. As described, the cutting means consists of a saw blade. The carriage 16 is reciprocated parallel to the path of the pipe along rails 8 by a chain drive 13 from a motor 12. The saw blade 20 is mounted on a shaft 26 supported in bearings 31 on a plate 11 which is slidable along rods 27 in a direction parallel to the path of the pipe, the rods being mounted on a plate 24. The movement of the saw relative to plate 24 permits floating of the saw during cutting to accommodate differences in the speeds of the pipe and carriage. The movement of plate 11 is against springs which urge plate 11 to a central position in which the plate can be releasably held by a solenoid-operated mechanism 40 during movement of the blade 20 into cutting engagement with the pipe. The plate 24 is carried by arms 18 supported on pivots 22 on the carriage 16 and is movable about the pivots by a hydraulic unit 25 to move the saw into and out of cutting engagement with the pipe. The operation of the machine is controlled by a selected one of limit switches L7A, L7B, L7C engageable by the pipe as it issues from a pipe forming machine and by limit switches L2, L3, L5, L6 operable by a dog 67 on the carriage 16. In operation, actuation of the selected switch, say L7A, by the free end of the pipe 9, starts the forward movement of carriage 16 by energizing motor 12. Limit switch L6 is then actuated to cause solenoid 40 to release the plates 11, 24 together to permit floating of the saw and actuates cylinder 25 to move the saw into engagement with the pipe. If during sawing, the speeds the pipe and carriage differ, plate 11 moves relative to plate 24 and a pinion associated with plate 24 is rotated by a rack on plate 11 to alter a potentiometer 65, 66, the varying voltage, which can be observed on a motor 63, being observed by the operator or used automatically to vary the speed of the carriage so that it matches the speed of the pipe. After the pipe is cut, switch L5 is actuated to cause cylinder 25 to retract the saw and solenoid 40 to lock the plates 11, 24 together. Thereafter switch 43 is actuated to effect return of the carriage to its initial position. During sawing, the pipe is supported by a structure 14 on the carriage and run-out tables 15 which are joined together by beams 79 and are movable by a cylinder 74 at a faster speed than that of the pipe so as to separate a cutpiece from a following piece. Each table 15 has a V-shaped frame 89 which is rockable about a pivot 81 in one direction or the other by cylinders 97, 98, the arms of the V carrying adjustably-spaced rollers 93 for supporting the pipe. The structure 14 is of similar construction to the tables 15. After severing of the pipe, the cylinder 74 moves the cut-piece at a faster speed and a selected cylinder 97 or 98 is actuated to rock the frames 89 in one direction or the other to eject the cut-piece.