GB1397512A - Apparatus and method for necking in cylindrical bodies - Google Patents

Abstract

1397512 Necking-in open can ends GULF & WESTERN INDUSTRIAL PRODUCTS CO 27 April 1973 [17 May 1972] 20260/73 Heading B3E A method of necking-in an open can end portion 16 using an apparatus A comprises gripping the inner 14 or outer 12 surface of a body B over a major portion of its circumference and over a substantial portion of its length with an expandible and contractable gripping device C, positioning a rotatably mounted female forming roller H having a circumferential arcuate groove 120 and a rotatable male forming roller I having a circumferential arcuate rib 162 receivable in the groove about the open end portion, and moving the rollers to form a smoothly curved inwardly directed circumferential bead in the end portion, the rollers H, I being so shaped and dimensioned as to produce an outwardly directed circumferential hump 250, Fig. 10. A mandrel C has a plurality of spaced axially extending slots 23 to define gripping members 34. A conical wedge portion E is positionable within a threaded bore 40 for expanding the members 34 outwardly from axis 42. The mandrel is rotatably mounted in a bearing D which is driven by a motor 28 via pulley 22. The rollers H, I are mounted on a structure G which includes a block member 56 which receives shafts 66, 68, Figs. 5, 6, having threaded ends 70, 72 threaded into blocks 78, 80. Bearing blocks 80 are rotatable with shafts 66, 68 about axes 90, 92. Respective shafts 102, 156 extend through blocks 78, 80 on which rollers H, I are mounted. Shafts 102, 156 are eccentrically mounted so that the axes of the rollers are offset from the shaft axes. Bearing block 80 is yieldably biased towards block 78. A block member 190 is secured to block 56 and receives a set screw 194 in a bore 192 which is adapted to adjust a coil spring 196. The force on the block 80 tends to rotate the block about axis 92 to move the roller I towards roller H. Levers 206, 208 are secured to shafts 102, 156 to enable the moving of the rollers to contact the open end of the body. The mounting block 56 is slidable on a base (220), Fig. 4 (not shown), for movement toward and away from the mandrel C. Bearing block 80 may be held in a predetermined spaced position relative to block 78 by the provision of a pin 144 and adjustable set screw 148. In operation, a can body B is mounted on mandrel C and members 34 are adjusted to grip the inner surface 14. Mounting block 56 is moved towards the mandrel to position the rollers on either side of the cam wall, a stop collar 126 being used to locate accurately the roller H with the open end portion. Motor 28 is energized to rotate the mandrel and can. As the roller H is moved towards the roller I an outwardly extending flange is formed. The roller I is then moved towards axis 42 of the can by rotating lever 208. Rib 162 of the roller I engages surface 12 of the can and moves into groove 120 of the roller H to reduce the diameter of the can at end portion 18.