Patent GB-945455-A (GB)
Title: Improvements in or relating to devices for interleaving sheets
IPC: B41L1/00
Filed: 1962-08-20
Abstract: 945,455. Delivering sheets; stopping printing machines. C. R. PATTERSON. Aug. 20, 1962 [Oct. 25, 1961], No. 31860/62. Headings B6C and B6H. [Also in Division B2] A device for interleaving sheets to form sets containing two or more sheets comprises a first station adapted to receive a plurality of first sheets one after the other, a support for a stack of second sheets to be interleaved with said first sheets, feed means for separating a second sheet from said stack and for positioning an edge thereof adjacent the corresponding edge of a first sheet at said first station, a delivery station for the interleaved sheets and conveyer means for engaging said first and second sheets at said first station and for transferring said first and second sheets in superimposed relationship to said delivery station. The interleaving device is detachably secured to a printing machine, the delivery grippers of which are carried on pivoted arms driven from the printing machine and deliver printed sheets to an intermediate platform 41, Figs. 2 and 3, the feed table 13 supporting a pile of carbon sheets 42 to be interleaved with the printed sheets. Each carbon sheet is supplied with adhesive along its leading upper margin and raised to be adjacent a printed sheet on the platform 41 with its leading edge against guides 132, Figs. 2, 3 and 11, the pair of sheets then being delivered together by auxiliary grippers 43 on arms 46, 47 oscillated in synchronism with the printing machine delivery grippers to a table 42, where adhesive is applied to the leading upper margin of the printed sheet. The printing machine drive shaft also oscillates a cam-shaft 61. As the arms 46, 47 are oscillated, the grippers 43 are caused to move along the path 68A, 68B, 68C. A cam 83 on the shaft 61 rocks a cam 70 pivoted at 71 to a side frame, and the cam 70 controls a gripper lever 77 through a rod 76. The gripper fingers 88, Fig. 3, of the grippers 43 are arranged to open and shut for gripping and releasing sheets under the control of a cam 91 through a rod 98 and a bar 101. The means for raising the carbon sheets comprises a suction bar 112 oscillated by levers 114 under the control of a lever 131 secured to the shaft 48 of the arms 46, 47, the lever 131 causing to be oscillated a shaft 127 carrying a cam 126 controlling the levers 114, which levers also raise the sheet guides 132, the sheet then being held by suction means comprising a chamber 134, Fig. 11. The shaft 127, Fig. 10, also oscillates a pin 150 which produces a vertical reciprocation of an assembly comprising an air blast tube 138, Figs. 10 and 11, for separating the edges of the carbon sheets, and fingers 141 engaging the top of the pile of carbon sheets. When the top of the pile has reached a low level pre-selected by a screw 183, the fingers 141 allow the screw 183 to descend far enough to close a switch 181 and, through a delay relay 184, energize a solenoid 179 to move a shield 168 and allow a pawl 158, oscillated from the shaft 51 of the printing machine delivery gripper arms, to engage the ratchet wheel 157 and raise the table 13. Adhesive is applied to the carbon sheets by depending fingers 197 of arms 196 pivoted to a carrier bar 186, the fingers being oscillated between contact with the sheets and an adhesive container. The amount of adhesive applied is controlled by a vertically adjustable rod 200. One end 191 of the bar 186 is bent and inserted in an opening in a pinion 192, whereby the fingers are oscillated by a gear segment 194 on the shaft 127. The sheets on the table 44 also have adhesive applied thereto by a similar mechanism, the gear segment 221 being oscillated through a lever 223 and a spring connecting device 224 from the arm 47. Mechanism for controlling the number of sheets to be formed into an assembly comprises a plurality of cams 253 to 259, Fig. 7, mounted on a rock shaft 236 and movable axially along the shaft by means of a manual selecting lever 261 to bring a selected cam into alignment with a roller 283 on a lever 281 pivoted at 282. The shaft 236, Figs. 7 and 9, is oscillated by the arm 46 acting on a disc 239. Each cam comprises a series of equally spaced notches round its periphery, some of which notches are deeper than the rest, the deeper notches also being equally spaced. When the desired number of sheets has been delivered, as determined by the lever 261 and a knob 252 which determines the amount of rotation of the cams, the roller 283 engages a deeper notch, and a pin 286 is projected into the path of the lever 223 to prevent adhesive being applied to the top sheet. A valve 292, Figs. 7 and 13, is also actuated to cast off suction from the bar 112, so that no carbon sheet is fed next cycle. Suction is applied cyclically from a supply conduit 293 through a rotary valve 297 to the suction chamber 134 and, through the above-mentioned valve 292, to the bar 112. The valve control member 309 is oscillated from the shaft 61 through a link 313. Detecting absence of sheets; stopping printing-machines.-If either a printed sheet or a carbon sheet is absent from position to be engaged by the grippers 43, resultant loss of vacuum in the system will be detected by a pressure differential switch 301, Fig. 13. If this occurs at the same time as a microswitch 321 is closed by a resilient member 322 on the arm 46, which is each time the grippers 43 approach their sheet-engaging position, a solenoid 316 is energized and activates the top lever 319 to stop the printing machine. If, however, the carbon sheet feed is skipped by the valve 292, the port 303 of the latter is closed, so that no loss of suction occurs in the rest of the system, and the solenoid is not energized.