Patent GB-831010-A (GB)
Title: Process of and apparatus for severing predetermined lengths of glass tubing
IPC: C03B33/06
Filed: 1957-04-12
Abstract: 831,010. Severing glass tubing. EGYESULT IZZOLAMPA ES VILLAMOSSAGI R. T. April 12, 1957 [April 13, 1956], No. 12043/57. Class 56. In the severing of predetermined lengths of glass tubing continuously delivered, as from a tube drawing machine, along a predetermined path at a substantially uniform velocity, the tubing is heated in an annular section by a moving cutting torch and the tubing is stretched to sever it, the flames always sweeping the middle portion of the stretched tubing so that the edges of the severed parts are rounded off by the flames of the cutting torch. The apparatus comprises a support 1 with a track 3 on which a carriage 2 is reciprocated at the same speed as tubing 19 continuously fed by rollers 5 from the drawing machine, the carriage 2 being driven from the rollers 5 by sprocket wheel 6, chain 7 and, on track 3, sprocket wheel 8 on a shaft 9, bevel gearing 10 and sprocket wheels 11, 12 driving an endless chain 13 having a pin 14 engaging a transverse slot 15 in the carriage 2 which allows the pin 14 to move across the carriage at the end of each run of the chain 13. The annular burner 17 is adjustably mounted at the front of a hollow drum 16 rotatably mounted in a support 29 on a base 24 slidable on a dovetail guide 25 on the carriage 2. The burner 17 gives radially inwardly directed flames 18 to impinge on the tubing 19 and is supplied with gas from a supply valve 30 through a flexible hose 31 over rollers 32, 33 and pipe 100 in drum 16, the hose 31 being wound on and off a hose drum 36 on drum 16, a counterweight 53 being provided. The drum 16 is rotated by reciprocation of the carriage 2 by a metal rope wound round the drum and secured resiliently to opposite ends of the support 1 and passing over guide rollers on the carriage. Ahead of burner 17, clamping jaws 40, 41 are pivotally mounted at 42 on a base 38 slidable along dovetail guide 25 on carriage 2, the jaws being drawn together by a spring 43 and interconnected by segmental gears 44, 45. The lever 46 carrying upper jaw 40 extends beyond the pivot 42 at 47 to cooperate with a cam 48 of a bell crank lever 49 pivoted at 51, the roller of lever 49 engaging an upwardly inclined guide track 92 at the rearward position of carriage 2 to force the jaws into clamping engagement with the tubing 19 and engaging a downwardly inclined guide track 94 adjacent the forward position to cause the jaws to release the tubing 86 separated from the main tubing 19. To separate the tubing, the jaws 40, 41 and the burner 17 are moved forwardly at a greater speed than the carriage 2 and tubing 19 towards the last part of their forward movement so as to stretch the softened portion of the tubing and to maintain the burner centrally thereof, by a bell crank lever 55, 58 pivoted to the carriage 2 at 54 and connected to the bases 38 and 24 by ties 56 and 57 respectively and which are positioned at such distances from the pivot 54 as to give the base 38 about twice the additional speed of the base 24 over the speed of the carriage 2 and tubing 19. The arm 58 of the lever engages a track 59 having an inclined part 95 to give the additional forward movement. The separated tubing 86 released from jaws 40, 41 is then gripped by rollers 60, 61 and fed onto a conveyer band, both moved by a chain 69 from a sprocket wheel 68 on shaft 9 so as to move the tubing 86 faster than the tubing A. As the tubing 86 reaches a stop at the end of the conveyer, arms on a shaft to one side thereof are pivoted to move the tubing sideways on to supporting arms.