Patent GB-831267-A (GB)
Title: Improvements in or relating to rotary duplicating machines
IPC: B41L7/08
Filed: 1956-05-25
Abstract: 831,267. Printing machines. RITZERFELD, W., and RITZERFELD, G. May 25, 1956 [May 28, 1955; March 29, 1956; April 12, 1956], No. 16258/56. Class 100(2) Copying documents; rotary machines; cylinder trips. A machine for printing selected lines of text spaced apart on a rectographic or inked master sheet in juxtaposition on a copy sheet by means of an impression roller movable towards and away from a rotatable printing element to which the master sheet is attached comprises electromagnets for controlling the movement of the impression roller, setting means for selecting lines to be printed by operating electric control means, and switching means closed in turn by a switching member rotating synchronously with the printing element, whereby at the instant a switching means corresponding to a particular line is closed, the magnet will be energized to cause the line to be printed, provided that the corresponding control means has been operated by the setting means. The printing drum 1, Fig. 1, is driven from a motor through a shaft 51 and one-revolution clutch 52 released to stop the drum by a cam 56 and lever 57. The copy sheet 21 is fed by rollers 22, 23 between the drum and an impression roller 10 mounted on arms 25 pivoted on a shaft 26. The roller 10 is moved towards and away from the drum by toggle levers 16, 17. The machine is set for printing the whole text or for interrupted printing by control levers 9, 62 which set levers 13, 64 on scales 14, 63 so as to adjust the printng pressure by rotating eccentric shafts 15, 65, and also close switches 11, 110<SP>1</SP> to supply current to the motor and other electrical mechanism. The roller 10 is moved towards the drum by links 49 actuated by electromagnets 28 and away from the drum by springs 29 on further magnets, or the magnets 28 may be reversible. A shaft 34 rotated in synchronism with the drum carries an arm 35 which on rotating closes in turn each of a series of contacts K corresponding to one line on the master sheet 2, each of which is in the circuit of the magnets 28 and of a second contact closed by a key of a keyboard 19, there being a key for each line. Selected keys are pressed and latched, and the magnets are energized each time the arm 35 closes a corresponding contact. After the drum has stopped rotating, an arm 60 on the shaft 51 closes in turn a third series of contacts K200 in the circuit of a magnet 61 and in series with further contacts closable by keys in a second keyboard 20, so that the magnet 61 is energized once for each key in the keyboard 20 which has been selected. Each energization of the magnet 61 causes through a mechanism 37 a second arm 36 on the shaft 34 to be rotated one step equal to a line space contrary to the direction of rotation of the shaft 34. The arm 36 closes a further series of contacts K in series with said contacts closable by keys in the keyboard 20. As long as selected keys are not released, printing of selected lines can be repeated as often as desired, but when the keyboard 20 is used the lines printed are progressed by the stepping of the arm 36, i.e. if the 1st, 2nd and 3rd lines are printed in one cycle, the 4th, 5th and 6th will be printed in the next, because the arm 36 is moved back three steps. A zeroizing key is provided, which opens all the selected contacts and also energizes a magnet 76 which acts through a lever 77 to restore the arm 36 to its initial position. In another form of selecting mechanism, Fig. 11, a slide 212 is moved together with a pointer 218 by a handle 216 over the copy to a desired line and the handle 216 is depressed to rock a selected lever 221 and close a contact 219, the lever 221 being locked by a latch 223, and a glow lamp 207 corresponding to the line also being lighted. Individual lines can be zeroized by moving up the handle 216, a pin 226 thereon releasing the latch 223, or all the contacts can be opened by means of a lever 228. When the cylinder 10 is moved away from the drum 1, it is rotated from the clutch 52 through a chain drive 44, 46, 45, so as to eject the printed copy-sheet. In another form, Fig. 13, the shaft 34 carries discs 107, 108 supporting rollers 109 corresponding to the lines, each roller in turn actuating a cam lever 110 or 111. Magnets 28a and 28b energized in the same way as magnets 28 already described, move clutch members 112, 113 into the path of the cam levers, the movement of which is then transmitted by levers 119 and links 120 to the cylinder-operating toggles 16, 17. In this form, the feed rollers 22, 23 are rotated by a cam 106 on the drum, through a roller 104, bell-crank 102, link 101, and toothed wheels 100, 24. In another form, Fig. 17, the cam levers operate the cylinder 10 without the interposition of clutch members, and the rollers 154 are individually and selectively set in position to actuate the cam levers by magnets 28a energized by contacts K, Fig. 17, closed as described above with reference to Fig. 11. On rotation of the drum 1, the magnets are deenergized by automatic opening of a contact Tli. A zeroizing key 61 energizes magnets 28b to retract the selected rollers, a contact T12 in the zeroizing circuit also being opened when the drum rotates. In another form, Figs. 18 and 20, rollers 170 are selectively moved into operative position by an electromagnet 175 on the end of an arm 174 on the shaft 34, the magnet being energized through a sliding contact 177, and a contact 176 engaging in turn contacts K1-K12 connected to contacts K selectively closed by the mechanism described with reference to Fig. 11. On depressing a lever 182, a clutch 178, 179 is engaged to rotate the shaft 34. Before the shaft 34 returns to its initial position, a lever 186 acts on a pawl 187, which engages a ratchet wheel 188 to rotate the drum 1. Specifications 735,181 and 831,268 are referred to.