GB701137A - Metal stock drawing apparatus - Google Patents

Abstract

701,137. Drawing. CALUMET & HECLA CONSOLIDATED COPPER CO. Dec. 5, 1951 [Feb. 12, 1951], No. 28534/51. Class 83 (4) A drawing machine comprises a frame, a pair of spaced drums rotatably mounted thereon, means for driving said drums alternately in opposite directions, means for securing end portions of the stock alternately to the drums for coiling the stock on one of the drums and uncoiling it from the other drum, and draw dies of different size successively engageable with the stock between said drums as it passes from one drum to the other. The drums 11, 12 are driven from a reversible electric motor 18 through clutches 17. Carriers 23, 24, carrying dies 27, Fig. 5, and guide bushings 29 are supported on a square section shaft 25 rotatable to bring a required die 27 into alignment with the path of the tubular stock S. The shaft 25 is also reciprocable in cylinders 40, 41 so that a plate 44, fixed to the shaft and carrying a series of wedge type clamping jaws 46, 48, moves in one direction or the other to grip the end of the stock projecting through a guide bushing 29 in one of the carriers 23, 24 and pushes it through a die 27 on the other carrier. The stock end is then gripped by a wedge type gripper 53 connected by a chain to a head 52 slidably mounted in a groove 50 in the drum on which the stock is being coiled. The carriers 23, 24 and plate 44 are mounted between end plates 33 and an arcuate side waU 32 having curved portions 39 engaging correspondingly curved recesses in a semi cylindrical cap part 37 supporting the assembly on the frame 10, so that the carriers may pivot about an axis perpendicular to the shaft 25 to allow the draw dies to align themselves with the stock. Lubricant is inserted into the end of the stock, before drawing, from a nozzle 70 and a plug 59, Fig. 7, of appropriate size is inserted into the tube end before it is projected through the die, to maintain the specified internal diameter of the stock. A spring 63 assists in maintaining the plug in position. Cutters 74, 75, having knives 75<SP>1</SP> are supported on the cylinders 40, 41, and may be selectively operated to cut off a deformed or damaged end of the stock before inserting a plug 59. The drums are shielded by fixed guards 67 and hinged, fluid operated guards 65. In a modification, Figs. 8-11 (not shown) a single die carrier is splined to a reciprocable shaft which carries an opposite side of the die carrier, two plates having gripping jaws for projecting the stock through the appropriate die. Drums 100, 101 may be positioned as axial extensions to the drum 11, 12, so that should the stock being coiled on either drum break, the stock on the drum would be shifted to the associated drum 100, 101 and the gripper 53 removed from the broken portion and re-engaged with the length of stock to be drawn.