Patent GB-190326277-A (GB)
Title: Improvements in Punching and Stamping Presses.
Inventor: MACKENZIE JOHN WILLIAM
Filed: 1903-12-01
Granted: 1904-11-10
Abstract: 26,277. Mackenzie, J. W., [Bliss Co., E. W.]. Dec. 1. Punching; stamping; drawing.-A press for punching blanks for bottle caps, can heads, &c., from sheet material has a variablefeed mechanism so that a sheet may be cut up into blanks of any size, the blanks being cut successively in rows, and successive rows "staggered with respect to each other. By the use of suitable die and punch mechanism, the press may stamp or draw up the blanks. The sheet is held in a gripping-device 6, Fig. 3, on a slide 10 fed laterally on a carriage 9 which is fed forward on the bed 3. The slide is fed laterally one space at each stroke of the punch 174 by means of a rack engaging a long pinion in the bed, the pinion being intermittently rotated from the driving-shaft 7 through a rocker 20. This rocker also actuates a pawl and ratchet-wheel 12 for advancing the carriage 9 through rack and pinion gearing. During the punching of a row of holes, the pawl is lifted from the wheel 12, but at each end of the row, the slide engages one of two pivoted dogs to depress the lifter so that the carriage is fed forward one step for the next row. The links 18, 46 for transmitting the movement of the rocker to the carriage and slide are adjustably connected to the rocker so that the forward and lateral feeds may be varied. The long pinion is operated by a rack sliding in the bed, and actuated by pawls engaging two sets of oppositely-disposed ratchet teeth on the rack. Each pawl is held out of engagement with its ratchet teeth during alternate rows of holes by a shield, which is moved by the slide 10 at the end of each stroke to release the inoperative pawl, and to disengage the operative pawl so that the feed of the slide is reversed. The two sets of teeth are intermediately spaced so that the first feed step for each row is only one half of the pitch of the blanks to produce "staggered" rows. The carriage and slide are locked after each feed to ensure the correct position of the sheet. The carriage is locked by pins 69, 70, Fig. 5, engaging pitched holes 68 in strips 67 on the bed. The pins are carried by rock-shafts 71, 72 operated at periods corresponding to the forward feed of the carriage. The slide is locked by a pin 126 engaging a notched bar 124 on the slide, the pin being disengaged at each lateral feed of the slide. The driving-shaft is provided with a clutch controlled by a handle 142. When the slide reaches the end of its traverse with the carriage in its most advanced position, the clutch is disengaged by the action of one of the two dogs previously mentioned. The clutch handle is also connected to the locking-pins of the carriage and slide so that they may be withdrawn by moving the handle in the opposite direction to that in which it is moved to start the machine. The punch is provided with a " knockout " operated by a lever 192 pivoted on the main slide 175. The die is provided with a spring ejector, withdrawn by a cam on the main shaft. When the blank is both punched and drawn up, a device for removing the blank is provided, consisting of pivoted jaws carried by a slide 199 operated from the main shaft, the jaws engaging a slide having lost motion relatively to the slide 199, so that the jaws open and close as the slide reciprocates. Gauge-stops 152 for the sheet are withdrawn by the movement of the handle to start the machine. A die and punch 176 are provided for cutting-up the scrap.