Patent GB-190418776-A (GB)
Title: Improvements in Printing Presses
Inventor: WHEATLEY WILLIAM HUMPHREY
Filed: 1904-08-30
Granted: 1905-01-19
Abstract: 18,776. Wheatley, W. H., [Scott, W.]. Aug. 30. Rotary machines; lithographic and like printing; feeding sheets ; associating and delivery apparatus ; set-off, preventing.-Relates to r o t a r y machines having one or more pairs of printing and impression cylinders, making two or more revolutions for e a c h sheet printed, and to feeding, associating, and d delivery apparatus for machines of this class. Fig. 1 shows an arrangement of machine for printing in one, two, or three colours. An impression cylinder 2 and a printing- cylinder 3 are arranged above the second impression cylinder and printing-cylinder 5, respectively, the printing - cylinders being arranged on one side of the impression cylinders, but located one above the other. The sheets are transferred from the cylinder 2 to the second impression cylinder by a transfer cylinder 20, but for printing i one colour the sheets may be fed directly to the second impression cylinder, and the upper cylinders dispensed with. If it is desired to print in three colours, a third pair of cylinders 61, 62 and a transfer cylinder 63 are arranged at about the same horizontal level as the cylinder 2. The inking-apparatus 6, 7 for the cylinders 3, 5 are arranged under the feed-board 60, and, when the machine is for planographic printing, damping- apparatus 18 are provided. An inking-apparatus 64 and, if necessary, a damping-apparatus 65 are applied to the cylinder 62. Each inking-apparatus 6, 7 is mounted on a frame 8 arranged to slide on rollers 9 and provided with a gear 10 meshing with the rack shown. The gears 10 may he rotated by the hand-wheels 11 to run back either inking- apparatus independently of the other. The frames 8 are in turn carried by a frame which slides on rollers 14 and is operable by a fixed rack 17, gear 15, and hand-wheel 16 to move the two inking-apparatus, together, away from the printing-cylinders. The transfer cylinder 20 is provided with grippers, or sheet-carriers 23<a>, and is preferably partly surrounded by a curved guide 21 against which the sheets are blown as they are carried by the cylinder, to prevent the printed side of the sheet from being smudged. For this purpose, air from a blower &c. is conveyed by a pipe 23 to the interior of the cylinder 20 and issues from the perforations 22. The air may be heated to dry the impression. The printed sheets pass over guides 29 through tapes 25 &c. to the delivery apparatus 24, which is shown as a drop delivery, but may be of other suitable kind. A receiving-cylinder 28, for associating the sheets, is placed in the sheet path 25, preferably tangential to it. This cylinder, like the impression cylinder or cylinders, makes two or more revolutions to each impression. From the cylinder 28, the sheets pass over the guide 30 and tapes 31 to the delivery mechanism 24. The second impression cylinder and cylinder 28 are provided with the usual grippers 32 and with lifting-fingers 33 for delivering the front edges of the sheets over the guides 29,30. The delivery apparatus is operated by a rack-bar 34 reciprocated by a crank disc 35 on a shaft 36 driven from the power shaft 37 by gearing 38, 39, 40, 41, 42, 43, so proportioned that the shaft 36 makes one quarter, and the shaft 44 one half, the number of revolutions of the printing-mechanism. The impression cylinders are in eccentric bearings 45, 46, operated, to move the cylinders away from the forme cylinders at alternate revolutions, by adjustable rods 51 connected to a crank shaft 52 rocked by an arm 53, rod 54, arm 55, and cam 57. The printing-mechanism is driven in the usual manner by gearing from the shaft 37, and the cylinder 28 is driven by the pinion 59. The feed-board is shown in position for feeding the sheets to the cylinder 2, but it may be placed as shown by dotted lines for feeding the sheets to the cylinder 61 for three-colour printing. The front gauges or stops 67, Fig. 4, are mounted on a rock-shaft 66 operated by the cam 68. One or more auxiliary stops or gauges 71, in the same line with, or very slightly ahead of, the gauges 67, are provided, to engage the edge of the sheet and prevent its buckling or being injured when it engages the front stops 67. These auxiliary gauges 71 may be formed as one continuous blade, or as several gauges, each presenting an extended contacting portion to the advancing sheet. The gauges 71 are carried by arms on a shaft 73 rocked by a lever 74<a> and cam 74, and rest on the usual tongues 79 attached to the feed-board. Fig. 5 shows a modification in which the auxiliary gauges 81 are mounted on a rock-shaft 82 operated by a cam 84. The delivery apparatus is arranged so as to deliver the printed sheets, either printed side upwards or printed side downwards, upon the delivery table 130. The delivery apparatus comprises a carriage 85, Figs. 1 and 10, running on guiderails 88, and provided with gears 90 in gear with stationary racks on the framing. Rotating with the gears 90 is a pinion in gear with a sliding rack, reciprocated by a wheel 93 rotating with the pinion 94 operated by the rack 34. In the carriage 85 is a sheet-turning cylinder 86 geared to the wheels 90, and provided with grippers 103 on a shaft having an arm 100, operated, to open the grippers at certain points in one of the revolutions of the cylinder, by cams 97, 98 pivoted loosely on the shaft 99 of the carriage. The cams 97, 98 are rocked into operative positions by a cam-groove 105 in a bar 104 adjustably fixed on the framing by screws and slots 107, 108. On arms pivoted on the shaft 99 of the carriage are friction rollers 109 resting on the cylinder 86 and adapted to feed the sheet over the cylinder. The gripper-gap of the cylinder 86 is provided with adjustable bridgepieces on which the rollers 109 run ; and the rollers 109 also are adjustable transversely on the shaft 99. A sheet stop or gauge is applied to the grippers 103. On the carriage 85 is a roller 118 carrying an apron 119, one end of which is attached to the machine framing at 120. The apron winds on and unwinds from the roller 118 as the carriage moves, the winding being effected by a spring arrangement applied to the roller, or preferably by tapes 121 attached to a spring-pressed tension frame. A second apron 125 fixed at one end at 127, similarly winds and unwinds from a roller 126 connected by the tapes 128 to the tension frame. An ordinary delivery board may be employed, but preferably several boards 130 are employed, carried by angle-irons or supports 132 attached to two pairs of endless chains 131, actuated to lower the boards gradually as the sheets are delivered thereon. The chains are driven very slowly by a transverse shaft 134 driven by gearing 154, 153, 151, 150 from a shaft 149 driven by worm gear from a shaft 145. This shaft 145 is driven by a friction pulley 144 engaging the face of a friction disc 142 on a shaft 143 geared to the shaft 36. The cylinder 28 takes alternate sheets, carrying them round and returning each sheet into the sheet path in register with the following sheets; but when the sheets are to be delivered singly, the cylinder 28 is rendered inoperative and the carriage 85 is driven at increased speed by placing the crank disc 35 on the shaft 44. When the sheets are delivered printed side down, each sheet, or batch of sheets, is guided into the grippers of the sheet-turning cylinder 86 by the guides 156, 157. The cylinder 86 carries the leading edge of the sheet partly round and releases it, the sheet being reversed as it is fed out by the cylinder 86 and rollers 109. The sheets may be delivered to the upper or underside of the apron 125, the apron acting in the latter case to deliver the sheets straight, as the sheets have a tendency to cling to it. When the sheets are to be delivered printed side up, the cylinder 86 is omitted or rendered inoperative, and the carriage 85 is provided with usual means for delivering the sheet, such as the grippers 160, 161 and sheet stop 166.