This invention relates to printer slotters used for pri […]
This invention relates to printer slotters used for printing and slotting carton blanks, usually of corrugated board, the same being in the nature of an improvement on the roll shaft adjustments described and claimed in United States Patent No. 2,191,988, granted to Henry B. Greenwood and United States Patent No. 2,259,441 granted to Thomas S. Fitohett.
In response to the demand for machines of increased capacity, even beyond those described in the above patents, the operating speeds of the machines have been extensively increased and for the same reason the number of blanks supported on the machine for feeding and hence the weight of the pile of blanks supported at the feed end has also been increased. These blanks, before they reach this machine, are cut to the desired length, and they are fed to the rollers of the printer slotter by a recriprocating feed which is mounted on the printer slotter frame and on account of the high speeds employed, the feed reciprocates at a correspondingly high speed, imparting to each blank an acceleration from zero to approximately one thousand feet per minute, this acceleration being necessary to raise the speed of th blanks to the surface speed of the rollers.
Because of the practice of using in the boxes and similar products made from the blanks passing through these machines, corrugated board of various thicknesses, it is necessary to provide an adjustment of the pressure rolls to accommodate them to the different thicknesses of board. An important object of the present invention is to :provide for the adjustment of the rollers to accommodate the machine to different thicknesses of material and at the same time to avoid any weakening of th frame which is incident to the adjustment of the bearings according to certain previous practices and to do this to better advantage than in the patents above cited.