Patent GB-190901824-A (GB)
Title: Improvements in Stencil Printing Apparatus.
Inventor: CHIPPERFIELD WALTER
IPC: B41L13/04
Filed: 1909-01-25
Granted: 1909-08-19
Abstract: 1824. Chipperfield, W. Jan. 25. Feeding sheets. - A rotary stencil printing- machine, of the kind iu which the stencil and its pad pass around two or more inking-rollers, is constructed with a feed-arm which springs the paper over the impression roller, the arm receiving a downward motion while holding the paper, and the impression roller being at the same time depressed from the stencil. The sheets are fed from a table arranged so that sheets displaced during the feeding operation are returned to normal position. The impression roller and feed mechanism may be put out of action, and, when returned to action, the roller is kept out of contact with the stencil until a sheet is in printing position. The sheets are fed from a board z, which is supported at one end by means of hooks 21 resting on pins 27 or 22 on pivoted arms 24 for feeding automatically or by hand. In the former case, the other end of the board with the file of paper on is kept raised against flanges 52 on a plate 7 by pivoted arms 1, which are controlled by a spring 3 attached to an arm 2 and to an arm 4 adjustable by moving a lever 5 in a rack 6. The top sheet of a pile, placed against an adjustable stop 76 on the board z, and kept flat by a plate 77 carried by levers 78, 79, is raised in a bent condition from the pile by means of an arm y mounted between a sleeve and a milled screw carried by a pair of levers u which are controlled by springs 35 adjustable by means of a screw 43 and acted on in order to depress the levers by means of arms 15 of levers 8 actuated by a cam 30. The extent of oscillation of the levers u is adjustable by means of screwed rods 44 with collars 46 which engage arms 47 on the levers. The arm y is rotated by segmental gears p, q, which engage a mutilated gear w on the sleeve in which the arm y is mounted. In the raised position of the levers u, the wheel p rotates the arm y, and a rubber or like pad r on the arm pushes the end of the top sheet into a curve, and, by the continued rotation of the arm, the paper is caused to spring over an impression roller s, freely mounted between the levers u. Catches x on the arm y prevent the paper from slipping beneath the roller s. When the parts u, y, s, are in their lowered positions, the segment q engages the wheel w and rotates the arm y over the roller s. The roller is then raised and grips the sheet against the stencil. The arm 30 is provided with an adjustable part held by a spring catch which permits the "head "space" at the top of a sheet to be regulated. The wheel w, when released from the segment p, is retained in correct position by a spring rod 37 which engages cam surfaces on the sleeve of the wheel w, and, when released by the segment q, it is retained by means of extensions 80 on the arm y which engages pads 82 on the plate 7 that guides a printed sheet from the machine. After a sheet is fed, the remaining sheets, if displaced, are allowed to return to their normal position by causing the roller s to rise from the table z and thus free the sheets. To effect this, the spring 3 is prevented from causing the return of the table with the roller s by means of a spring-controlled pawl 49, which is caused to engage a ratchet-wheel 48 on the shaft 2, and is released therefrom by a pin 50 on the extension of the lever u, when this is in its upper position. When the sheets are fed by hand, the table z is supported by the pins 22 and by means of guides in the levers u; and the segment p is put out of gear by moving a fixing-screw 12 in a slot 13, and the segment q is prevented from engaging the wheel w by reason of a partial rotation of the wheel w effected by means of the engagement of the extensions 80 and pads 82. The arm y does not rotate in this case, and the catches x on the arm serve as a stop for the sheet. The roller s may be held out of action to allow adjustment of the stencil and inking-devices by securing the lever 8 out of action by means of a pivoted plate 60, Fig. 6, with an irregular slot 84 adapted to engage a pin 54 on an extension 53 of the arm 8. The plate 60 is actuated by a double counterweighted lever 55 with a pin which engages a slot in the plate 50. The plate engages the pin 54 when the lever 55 is moved to the left, and releases it when returned to the normal position. For the first revolution after the release, the roller s does not engage the stencil, but after this the printing proceeds normally. The lever 8 may actuate a counting-train.