Patent GB-272846-A (GB)
Title: Improvements in punching machines
IPC: B21D28/24
Filed: 1926-12-06
Abstract: 272,846. Franklin Knitting Mills, Inc., (Assignees of Hug, F.). June 19, 1926, [Convention date]. Cards, punching.-In a machine for punching holes in a metal strip &c., as for metal jacquard cards for knitting machines, the metal strip 21 shown in plan in Fig. 3 is clamped to a block 27 on a flat bar 25, Figs. 3, 5 and 7, on a carriage 24, which is guided on tracks 23 on a hollow housing base 22 and is moved along these tracks by pins 48, 49 mounted on the bar 25 and engaged by cam surfaces 46, 47 on a helical cam 45 on a shaft 44 which is turned in one direction or the other by the mechanism described below. The metal strip is thus positioned under the dies 65, 66, Fig. 13, in a punching head i38 having a shank 69 engaging a member 70 of the punch machine proper. A treadle is now operated and by means of lever mechanism &c. a shaft is rotated and an eccentric thereon depresses the punch whereby a hole is punched in the desired place. The shaft 44 is again operated and the metal strip re-positioned, so that another hole may be punched in a different position, and so on until the strip has been punched in the required manner. A pointer 101 on the bar 25 moves over a scale 100 on the base 22 to facilitate the punching of the holes in the correct position. The. slugs pass on to the floor through an opening 81 communicating with the openings 79, 80 in the lower die 67. Selecting punches. The two dies 65, 66 are loosely and slidably mounted in the head 68, screws 71, 72 on the dies riding in slots 73, 74 and being acted upon by springs 75, 76. One or the other die is rendered operative to punch the metal when the punching head descends, by means of a manually operated lever 84, which can be positioned over the die 66 as shown, thus making this die operative, or alternatively over the die 65. Holes may thus be punched in two rows and they may be staggered as shown in Fig. 15 to suit a Jacquard knitting machine where the needles are staggered. The lever 84 has spring-controlled pawl detent devices to hold it rigidly over one die or the other, holding the metal strip in position. The strip having the usual previously-punched round holes at its ends is inserted between the block 27 and a clamping plate 28 thereon with one of its end holes 31 fitting over one of two pins 30 on the block 27. A thumb nut 29 is then operated to clamp the strip between the plate 28 and the block 27. The strip 21 fits in a runway 33 between the two sides 34 of a guide 32, and is held down by cross pieces and by a flat spring 38, which can be released by a handle 41 having a bevelled edge 43. Adjusting the strip. The shaft 44 is rotated in one direction or the other to adjust the strip over the punch by means of two ratchet wheels 50, 51 operated by respective spring-controlled pawls 52, 53 pivoted on a, lever 54 actuated by lever mechanism from the shaft 61, which has a handle for manual operation. When the pawl 52 is operating, the pawl 53 rides over a pin 102, and when the pawl 53 is operating, the pawl 52 rides over a pin 104. Spring bumpers are provided to take up the shock of the ratchets.