GB803657A - Improvements in pipe or tube cut-off machines - Google Patents

Abstract

803,657. Pipe-cutting lathes. AETNA-STANDARD ENGINEERING CO. Oct. 18, 1955 [May 16, 1955], No. 29695/55. Class 83 (3). A pipe-cutting machine of the type having a rotary-tool-head with circumferentially-spaced cutting-tools, a clamp for holding a tube stationary within said tool-head, and driving- means for the head, is characterized in that means for advancing and retracting the cutting- tools include a gear rotatably mounted on the head and differential-gearing connected to the driving-means for selectively driving the first gear at the same speed as, or faster or slower than said head, thereby to hold the tools stationary or to advance or retract them. A tube T, Fig. 1, moves over a conveyer 10 to the rotary-toolhead 11, where it is clamped by shoes 53, Fig. 3, while operated on by a number of cutters 16, Fig. 5, six in the example described. The tube is also clamped on the other side of the head by a gripping-device 13 which thus holds the wasteend and is moved along rails 27, 28, after the cutting-off operation to deposit the end on a shoot. Rotary tool-heads. A circular casing 30, Fig. 2, has a base-portion 31 supported on beams 33, and the circular portion is open at both ends to take the tube. Fluid-pressure-cylinders 12 operate arms 65 which control the tube-clamping-mechanism. The circular casing 30, Fig. 3, is provided with an inner-sleeve 35 which carries an " X " bearing at its inner end to support the ring 81 of the head. The tools 16 are carried in non-rotatable sleeves 70 which are fed radially by screw-and-nut devices, the screws 75 being rotated by bevel-wheels 78 engaging a ring 98 which has corresponding bevel-gearing on a side-face, and spur-teeth around its periphery. This ring-gear is rotatable relative to the supporting-ring 81 and is driven by a pinion 102, bevel-gearing 103, 104, Fig. 2, and shaft 24 from a gear-box 20, Fig. 1. A further gear-ring 90, Fig. 3, secured to the ring 81 constitutes the main drive for the head and is rotated by a pinion 93, bevel-gears 94, 95, Fig. 2, and a shaft 22 also driven from the main gearbox. Shaft 22 is driven by a two-speed changegear from belt-gear and a variable-speed electric motor 21 which also drives the sun-gear of a differential drive for shaft 24. The planetgears and supporting housing are driven by a positive-displacement hydraulic motor, so that the ring-gear 98 for the tool-feed may be rotated at the same speed or faster or slower than the main driving gear-ring 90. Arcuate clamping- shoes 53, Fig. 3, for holding the tube during cutting, are guided for radial movement and operated by rollers 49 on the shoes engaging cam-slots in a ring 46 supported inside the sleeve 35 and operated by the levers 65 (see above). Operation. Push-button controls are provided and the tube is moved into clamping- position, the main and waste-end clamps are closed, and an automatic cut-off cycle initiated. This includes rapid-advance of the tools, feed through the cutting-stroke and rapid-return of the tools to their retracted position. The main clamps are then released and the waste-end clamp moved by its carriage to discharge the end into a shoot. Specification 803,658 is referred to.