GB253714A - Improvements in flame cutting machines - Google Patents

Abstract

253,714. Hancock, L. J. June 10, 1925. Perforating and dividing by fusion. - In a flame cutting machine of the kind described in Specification 226,846, the tracer arm and blowpipe-carrying arm are mounted on a carriage traversable by an electric motor on rails alongside the tracer table and work bed in order to make continuous cuts of indefinite length in the side frames of locomotives &c. The integral tracer and pipe arms 17, 18 are pivoted at 19 to a gate 16, which is pivoted on a rost 15 mounted on a wheel carriage 14 traversable on a channel- or .H-section girder 2 through gearing 22 from an electric motor carried thereby. The pattern table 13 is carried by brackets 12 secured to the shafts of worm wheels 11, and may be tilted, so as to allow heavy work to be placed on the bed 1, by a hand wheel through bevel gear 8, 9 and worms 10. The tracer wheel is driven by a second electric motor and is guided by hand. In order that the carriage may be traversed when 'the limit of the normal reach of the arms has been attained, the traversing motor may be switched in by hand. automatically. For the latter purpose a plate 23 on the post 15 has a pair of contacts 24, 25 and a pivot 33 for a segment 26 and a telescopic arm 29, the other end of which is pivoted at 34 to the arm 17. The segment is connected to the arm 29 by a spring 30 and is normally fixed by a ball 31 pressed by a blade spring on the plate into the central notch 32. Just before the point is reached at which movement of the post 15 is required to continue the cut, the tension of the spring 30 overcomes the pressure of the ball and the segment is moved so that the ball engages one or other of the side notches, and this connects the contacts 24. 27 or 25, 28 and so operates the traversing motor in forward or reverse direction. When the tracer arm is moved in the reverse direction, i.e. round a curve, the spring again overcomes the ball and the segment is snapped over into central position so as to stop the motor. The bed plate is in sections so as to vary the length of travel of the machine. The tracer and pipe arms may be set to cut on a line parallel with the rails. Stops are provided on the carriage to prevent it overunning the track.