GB190706606A - Improvements in Stenciling or Reproducing Machines - Google Patents

Abstract

6606. Underwood, J. T. March 19. Copying documents &c.-In a rotary stencil printing-machine, the pressure roll 39, between which and the stencil-carrying drum 12 the sheet of paper passes, has journals 36 which rest upon pairs of rollers 34 carried by blocks 29 capable of vertical movement in guides 4 on the standards 2, 3. The shoulders 37, 38 on the journals 36 prevent endlong movement of the roll 39. The slotted ends of a spring plate 76, Fig. 7, are loosely attached to the blocks 29 by screws 51. The pressure of the roll 39 can be adjusted by means of a rod, a screwthread on which engages a threaded bevel-gear 93 meshing with a similar gear 91 on a shaft 96. Rotation of the shaft 96 produces vertical movement of the rod 91. The bevel-gear 93 rests upon a socket 90 pivotally attached to a pivoted lever 80. which is held in the position shown by a lug 84 upon an arm 85. By releasing the lever 80, the pressure of the roll 39 is relaxed. In a modification, a plate similar to 76 is pressed upon by a knife-edged cam on a rotatable shaft 43, Fig. 2. Fast upon the shaft 43 is a worm-wheel 56 engaged by an adjustable worm 58 carried by a housing 57 loose on the shaft. The housing is attached to the standard 3 by pivoted links 60, 61, a tongue on the link 60 entering a recess in the link 61. The pivot pin 67 can, in the position shown, move only in the direction of the arrow, and the pressure of the roll 39 is thus relaxed by the rotation of the shaft 43 and cam. The links 60, 61 may, however, be replaced by a single liuk, pivoted to the standard 3, which prevents rotation of the housing 57 in one direction. The worm gear may be omitted and the shaft 43 is then fitted with a crank. The journals 36 of the pressure roll may rest in the upturned ends of the plate 76 instead of upon the blocks 29. The stencil drum 12 is supported axially on the standard 2 but peripherally upon the standard 3 by means of rollers 14 on horns 13, Fig. 2, and a roller 17, Fig. 7. The drum is revolved by a handle 20 adjustably clamped upon the open end of the drum. The handle is constructed in two parts, as shown, in order that it may be folded vertically.