Abstract: A device for positioning printing material for use in a printing apparatus in which printing is applied to the printing material by passing the same through between an impression cylinder and a blanket cylinder, the device comprising positioning member disposed in an recessed portion formed on an outer surface of the impression cylinder, the positioning member including, a stopper with which a leading end of the printing material comes to contact, drive means for moving the stopper forward and backward in a direction of transport of the printing material, control unit for controllably driving the drive means while the impression cylinder is being rotated, and operation means for operating the control means. Accordingly, displacement of superimposed printed images in a direction of transport of the printing material resulting from the fact that the positioning member improperly positions printing material can be corrected rapidly and accurately.

Abstract: A pushing device is provided with an impression cylinder, sheet pusher for pushing a rear end of printing sheet, drive chain for driving the sheet pusher, and drive transmission mechanism for transmitting the driving force used to rotate the impression cylinder to the drive chain. The drive transmission mechanism includes a clutch which engages and disengages to permit and prohibit a transmission state of the drive transmission mechanism, clutch actuator for actuating the clutch in accordance with a signal from a control unit, and drive device for rotating a drive shaft for the drive chain. Accordingly, the position of the sheet pusher can be adjusted easily and properly according to a change in the size of the printing sheet, and a leading end of the printing sheet can be accurately positioned relative of holders provided on the impression cylinder.

Abstract: This invention relates to a color head for an offset press for printing curved articles such as cups, cans, tubes and the like and sheet-like or flat articles such as paper, metals, synthetic resins, and the like. In order to supply the quantity of ink necessary for each article to be printed onto the plate of a plate cylinder for printing the article, an ink roller rotatably provided inside an ink fountain is caused to rock during each printing cycle, in which one article is printed, by cam rings on the sides of the form roller and by rocking levers operated by these cam rings, and is brought into contact with the form roller within a predetermined angular area of the form roller. The quantity of ink supplied can be adjusted continuously without any steps, either manually or automatically, whenever necessary. The roller system used in the invention has a reduced number of rollers so as to shorten the path of the ink and to print each article with a uniform, suitable quantity of ink.