Abstract: A method of printing comprising includes spreading and flattening a plastic film web before passing the plastic film web through a first printing unit; and spreading and flattening the plastic film web after the plastic film web exits the first printing unit and before passing the plastic film web through a second printing unit.

Abstract: A variable cutoff cylinder alignment apparatus is provided. The variable cutoff cylinder alignment apparatus includes a plate cylinder support box for supporting an exchangeable variable cutoff plate cylinder, a blanket cylinder support box for supporting an exchangeable variable cutoff blanket cylinder and an alignment stop adapted to align the blanket cylinder support box and the plate cylinder support box. The plate cylinder support box supports an exchangeable plate cam and the blanket cylinder support box includes a blanket cam. The exchangeable plate cam is capable of contacting the stop and the exchangeable blanket cam is capable of contacting the plate support box to align the blanket cylinder support box and the plate cylinder support box. The plate cylinder support box and the blanket cylinder support box are capable of aligning cylinders of different sized cutoffs. A variable cutoff offset printing press and a method of aligning printing cylinders during a cutoff change are also provided.

Abstract: A printing press is provided. The printing press includes a first printing unit including a first plate cylinder, a first blanket cylinder and a first impression cylinder forming a first printing nip with the first blanket cylinder, a first bowed roller upstream of the first printing unit spreading a web before the web enters the first printing nip, a second printing unit downstream of the first printing unit including a second plate cylinder, a second blanket cylinder and a second impression cylinder forming a second printing nip with the second blanket cylinder, and a second bowed roller between the first printing and the second printing unit, the second bowed roller spreading the web before the web enters the second printing nip. A method printing is also provided.

Abstract: A variable cutoff printing press is provided. The printing press includes a first plate cylinder rotating at a constant angular velocity and printing on a web during each revolution about a first plate cylinder axis and a first blanket cylinder rotating at varying angular velocities during each revolution about a first blanket cylinder axis. The first blanket cylinder comes in and out of contact with the first plate cylinder during operation. A method of variable cutoff printing is also provided.

Abstract: A variable-diameter printing press cylinder is provided. The variable-diameter printing press cylinder includes a cylinder body, a first shell segment having a first circumferential end portion and a second shell segment having a second circumferential end portion. The first and second shell segments are mounted on the cylinder body via the first and second circumferential end portions. A method of varying a circumference of a cylinder in a printing press and a printing press are also provided.

Abstract: An offset printing press is provided including a plate cylinder and a fluid dispersing unit dispersing fluid to the plate cylinder. The fluid dispersing unit includes a vibrator roll, a shaft supporting the vibrator roll and a motor including a coil and a magnet. The coil is disposed about the magnet and the magnet or the coil is mounted on the shaft. The motor oscillates the vibrator roll axially. A vibrating assembly for a fluid dispersing unit of a printing press is also provided.

Abstract: A variable cutoff cylinder alignment apparatus is provided. The variable cutoff cylinder alignment apparatus includes a plate cylinder support box for supporting an exchangeable variable cutoff plate cylinder, a blanket cylinder support box for supporting an exchangeable variable cutoff blanket cylinder and an alignment stop adapted to align the blanket cylinder support box and the plate cylinder support box. The plate cylinder support box supports an exchangeable plate cam and the blanket cylinder support box includes a blanket cam. The exchangeable plate cam is capable of contacting the stop and the exchangeable blanket cam is capable of contacting the plate support box to align the blanket cylinder support box and the plate cylinder support box. The plate cylinder support box and the blanket cylinder support box are capable of aligning cylinders of different sized cutoffs. A variable cutoff offset printing press and a method of aligning printing cylinders during a cutoff change are also provided.

Abstract: A variable cutoff printing press is provided. The printing press includes a first plate cylinder rotating at a constant angular velocity and printing on a web during each revolution about a first plate cylinder axis and a first blanket cylinder rotating at varying angular velocities during each revolution about a first blanket cylinder axis. The first blanket cylinder comes in and out of contact with the first plate cylinder during operation. A method of variable cutoff printing is also provided.

Abstract: A variable-diameter printing press cylinder is provided. The variable-diameter printing press cylinder includes a cylinder body, a first shell segment having a first circumferential end portion and a second shell segment having a second circumferential end portion. The first and second shell segments are mounted on the cylinder body via the first and second circumferential end portions. A method of varying a circumference of a cylinder in a printing press and a printing press are also provided.

Abstract: A variable cutoff printing press is provided including a first plate cylinder with a first plate disposed about the first plate cylinder and having a first image portion. A first blanket cylinder transfers the first image portion to a web at a first location. A second plate having a second image portion is disposed about the second plate cylinder. A second blanket cylinder transfers the second image portion to the web at a second location. An impression cylinder contacts the first blanket cylinder and the second blanket cylinder via the web. The first image portion and the second image portion form one continuous image having an image cutoff length. A method of printing an image on a web with a cutoff using a variable cutoff offset printing press is also provided.

Abstract: A printing unit arrangement in a web-fed rotary printing press includes at least one printing unit 2a having a first and second plate cylinder 4, 6 and associated first and second blanket cylinders 8, 10 which are mechanically coupled via meshing gear wheels and which are commonly driven by one drive motor 12. A second printing unit of the printing unit arrangement includes a first and second plate cylinder 24, 26 and associated first and second blanket cylinders 28, 30. The first plate cylinder 24 and the first and second blanket cylinders 28, 30 are mechanically coupled via meshing gear wheels and are commonly driven by a first drive motor 42. The second plate cylinder 26 is individually driven by a second drive motor 46, and is engageable and disengageable from the associated second blanket cylinder 30 while the printing press is in operation, in order to perform flying edition changes or changes of a spot color.

Abstract: A tucking device for tucking a printing plate into a gap of a plate cylinder includes a tucker bar having a tucking surface and at least one magnet for creating a repulsive magnetic force at the tucking surface. An actuator connected to the tucker bar is used for moving the tucker bar to tuck the printing plate into the gap.

Abstract: A printing unit arrangement in a web-fed rotary printing press includes at least one printing unit 2a having a first and second plate cylinder 4, 6 and associated first and second blanket cylinders 8, 10 which are mechanically coupled via meshing gear wheels and which are commonly driven by one drive motor 12. A second printing unit of the printing unit arrangement includes a first and second plate cylinder 24, 26 and associated first and second blanket cylinders 28, 30. The first plate cylinder 24 and the first and second blanket cylinders 28, 30 are mechanically coupled via meshing gear wheels and are commonly driven by a first drive motor 42. The second plate cylinder 26 is individually driven by a second drive motor 46, and is engageable and disengageable from de associated second blanket cylinder 30 while the printing press is in operation, in order to perform flying edition changes or changes of a spot color.

Abstract: A web-fed rotary printing press (1) for alternatively printing, in a perfecting mode, a single web (10) or, in a non-perfecting mode, first and second webs (6, 8), comprises a first impression cylinder (16) having a plurality of first blanket cylinders (22a, 22b, 22c, 22d) and a corresponding plurality of second plate cylinders (24a, 24b, 24c, 24d) arranged along a periphery of the first impression cylinder (16). A second impression cylinder (18) located adjacent to the first impression cylinder (16) has a plurality of second blanket cylinders (28a, 28b, 28c, 28d) and a corresponding plurality of second plate cylinders (30a, 30b, 30c, 30d) arranged along a periphery thereof. In the perfecting mode, the single web (10) is passed over first impression cylinder (16) to be printed on a first side (10a) thereof and is afterwards passed through a gap (20) between the first and second impression cylinders (16, 18) to the second impression cylinder (18) to be printed on a second side (10b) thereof.

Abstract: A tucking device for tucking a printing plate into a gap of a plate cylinder includes a tucker bar having a tucking surface and at least one magnet for creating a repulsive magnetic force at the tucking surface. An actuator connected to the tucker bar is used for moving the tucker bar to tuck the printing plate into the gap.

Abstract: The web-fed rotary offset printing machine utilizes a blanket belt onto which two or more colors are offset and which prints the two or more colors at once onto a material web. The blanket belt travels about guide rollers which have a lesser mass and/or a lesser diameter than the form cylinders which offset the colors onto the blanket belt. If several impression nips—blanket to web nips—are formed along the travel path of the material web, they are located so close to one another that fan out register errors cannot occur.

Abstract: A printing unit has a frame and a plurality of printing cylinders, including a first plate cylinder, a first blanket cylinder, a second blanket cylinder mounted in the frame and forming a nip with the first blanket cylinder for receiving a web of material to be printed, and a second plate cylinder. A plurality of eccentric boxes are mounted on the cylinders and supported in the frame. A plurality of actuation assemblies are provided that are connected to the eccentric boxes. One of the actuation assemblies is connected to each of the eccentric boxes for moving the eccentric boxes such that the printing cylinders can be selectively positioned between a thrown-off position and an engagement position in regards to adjacent printing cylinders. Because of the use of eccentric boxes, lower rated and less complicated actuation assemblies can be used.

Abstract: The web-fed rotary offset printing machine utilizes a blanket belt onto which two or more colors are offset and which prints the two or more colors at once onto a material web. The blanket belt travels about guide rollers which have a lesser mass and/or a lesser diameter than the form cylinders which offset the colors onto the blanket belt. If several impression nips—blanket to web nips—are formed along the travel path of the material web, they are located so close to one another that fan out register errors cannot occur.

Abstract: A printing unit has a frame and a plurality of printing cylinders, including a first plate cylinder, a first blanket cylinder, a second blanket cylinder mounted in the frame and forming a nip with the first blanket cylinder for receiving a web of material to be printed, and a second plate cylinder. A plurality of eccentric boxes are mounted on the cylinders and supported in the frame. A plurality of actuation assemblies are provided that are connected to the eccentric boxes. One of the actuation assemblies is connected to each of the eccentric boxes for moving the eccentric boxes such that the printing cylinders can be selectively positioned between a thrown-off position and an engagement position in regards to adjacent printing cylinders. Because of the use of eccentric boxes, lower rated and less complicated actuation assemblies can be used.

Abstract: A printing unit arrangement in a web-fed rotary printing press includes at least one printing unit 2a having a first and second plate cylinder 4, 6 and associated first and second blanket cylinders 8, 10 which are mechanically coupled via meshing gear wheels and which are commonly driven by one drive motor 12. A second printing unit of the printing unit arrangement includes a first and second plate cylinder 24, 26 and associated first and second blanket cylinders 28, 30. The first plate cylinder 24 and the first and second blanket cylinders 28, 30 are mechanically coupled via meshing gear wheels and are commonly driven by a first drive motor 42. The second plate cylinder 26 is individually driven by a second drive motor 46, and is engageable and disengageable from de associated second blanket cylinder 30 while the printing press is in operation, in order to perform flying edition changes or changes of a spot color.