GB882925A - Improvements in methods of and devices for cutting tubing into lengths - Google Patents

Abstract

882,925. Sawing. SPIRO ESTABLISHMENT S.A. June 11, 1958 [March 11, 1957], No. 8003/57. Class 145. Tubing fed axially, whilst rotating on its own axis, from a helical seam tube making machine is cut into lengths by a saw 3 slidable on a splined shaft 7 carried by a mounting comprising arms 10, 16 on a sleeve 18 rotable on a barrel 20, the mounting being swung to feed the saw transversely in the tubing sufficiently to penetrate the wall thickness and the saw then being carried along its splined shaft by the tubing while the cut progresses circumferentially round until complete severing takes place after a complete revolution of the tubing. The saw shaft is driven by a motor 14 through gearing 12, 11 and the feed and withdrawal of the saw is provided by a hydraulic piston 36 and a plunger 38 having a pair of rollers 40, 41 engaged in slots 42, 43 in the barrel 20 and sleeve 18, the slot 43 being sloped at 43a so that, at the end of the forward plunger movement, the sleeve 18 is rotated relatively to the barrel. The barrel is held firmly by friction liners 22 in a split bracket 23 but can yield slightly if the saw does not readily penetrate the work or if it is necessary to adjust the initial position of the saw by means of a screw 24 to suit different diameters of work. A switch engaged by the end of the work energizes the motor 14 and sets a valve to supply hydraulic pressure to the piston 36 for the in-feed of the saw and another switch operated by the collar 4 of the saw at the end of its movement along the shaft 4 resets the valve for the return stroke of the plunger, the saw being returned along its shaft by an arm 44a, and stops the motor 14. The main motor of the machine can be stopped when the saw is cutting into hard material and is started by the closure of a contact by the saw mounting when full penetration has been made. Specifications 830,504 and 830,505 are referred to.