Abstract: An offset printing method includes creating halftone dots corresponding to a printed image and formed of printing ink, on a surface of a transfer cylinder and transferring the halftone dots to a printing substrate while the transfer cylinder rotates about its longitudinal axis. A halftone value in a printed image on the printing substrate is adjusted to a desired value by modifying a halftone dot size. The offset printing method improves the quality of the printed image by increasing the halftone dot size by a desired amount by providing a relative offset between a device that creates the halftone dots and the surface of the transfer cylinder.

Abstract: A device for simultaneous three-sided trimming of products in a plurality of cutting stations includes a common upper knife carrier operable in a vertical motion, blades to be attached to the upper knife carrier for at least front edge trimming and top and bottom trimming of the products and a first drive for driving the upper knife carrier. A conveyor system has top-related and bottom-related pairs of conveyor belts for conveying the products through the cutting stations of the device and a second drive driving the conveyor system. The first and second drives are self-contained, mutually independent drives connected to one another by control units. The top-related and bottom-related pairs of conveyor belts of the conveyor system are each driven by self-contained, mutually independent, position-controlled drives.

Abstract: A method for producing a control area to prevent scumming of a printing form that can be used for offset printing with dampening solutions, includes producing the control area separately from the printing form and joining the control area to the printing form thereafter. A cut-out is introduced into the printing form and the control area is inserted into the cut-out. A control area and a printing form having a control area are also provided.

Abstract: A method for feeding sheets to a printing technology machine improves reliability of feeding sheets and reduces an acceleration time from a base speed to a production speed. The sheets are conveyed onto a feed table in shingled formation by a first drive and are individually and successively conveyed from the feed table to a first processing station of the machine by a second drive. The sheets are conveyed onto the feed table before an acceleration of the second drive to production speed is completed and the first drive is accelerated to the production speed when the processing station has reached the production speed.

Abstract: A method for controlling a feeder of a gathering-stitching machine reduces the operating effort when setting the feeder, increases reliability when laying folded sheets on a transport device and improves quality during collating and stitching. Opening and closing times of grippers are regulated under program control, continuously and as a function of format when controlling the feeder of the gathering-stitching machine. Data relating to the dimensions and to the number of pages of the folded sheets is thus entered into a control device, from which data actuating signals for actuating elements of the grippers are generated.

Abstract: A sheet feeder for separating sheets from a stack and for feeding the sheets to a downstream sheet processing machine includes a first suction wheel and a second suction wheel. The first suction wheel is disposed above the stack and the second suction wheel is disposed downstream of the stack and below a sheet travel plane. The first suction wheel separates a respective sheet from the stack and the second suction wheel accelerates the sheet.

Abstract: A suction wheel attracts sheets by suction and transports them. The suction wheel contains a suction wheel body rotatable about an axis of rotation and provided with a plurality of suction openings formed in the circumferential surface of the suction wheel body. Accordingly, the suction wheel body is of a non-circular shape. In particular, the suction wheel includes an attraction area for attracting a sheet, a retaining area for retaining and conveying a sheet, and a release area for releasing a sheet. A sheet feeder ideally incorporates such a suction wheel.

Abstract: An electric brake device is provided for electronically controlled synchronous motors which are supplied with voltage by way of a converter. The synchronous motor contains a winding center point and that the winding center point is connected by way of an electric resistor and a switch to a ground point of the converter and that the phases of the converter that are connected to the ground point contain in each case a free-wheeling diode.

Abstract: A method for forming an auxiliary stack when a sheet stack is changed in a sheet delivery of a sheet-processing machine includes providing an auxiliary stack support for supporting the auxiliary stack during a non-stop stack change and multiple stop and separator elements disposed outside a stacking area in front of edges of the sheet stack to form a gap in a stream of sheets conveyed by a conveying system and released to fall onto the sheet stack. The sheet stack is lowered to form a gap for the auxiliary stack support, the stop elements for the front edge and the rear edge of the sheet stack are moved into a disengaged stand-by position before the main stack is lowered. For this purpose, the stop elements are equipped with remote-controllable actuating devices that are connected to a control unit. A device for forming an auxiliary stack is also provided.

Abstract: A method for delivering electric power to power consumers of a printing technology machine, which permits high availability of the machine with low idling losses, includes taking start-up time periods of the power consumers into account when switching over the power delivery to power consumers of a printing machine.

Abstract: A method of signaling or indicating a coloration condition upon a change of an operating condition in a printing press having a control unit, includes the steps of specifying a target ink density for a print job, storing the specified target ink density in the control unit, calculating an actual ink density using the control unit based on an actual operating condition of the printing press, comparing the actual ink density to the target ink density in the control unit, and emitting a first signal using the control unit when the actual ink density is within a range of tolerance about the target ink density stored in the control unit.

Abstract: A method for embossing products with a rotary embossing device includes controlling the rotation of at least one embossing roller as a function of marks that are present on the products and are detected by sensors. A folder gluer having a rotary embossing device is also provided.

Abstract: A method for drying printed material operates with the aid of a one-dimensional or two-dimensional array of radiation sources which can be driven individually or in groups. At the same time, the high-resolution image data describing the printing image or a content of printing forms for individual color separations is transformed into image data of lower resolution. Position data which describes the position of the printed image in the transport direction is also obtained from a device for transporting the printing material. Control data for modulation of an intensity of the radiation sources or groups of radiation sources of the array are generated from the image data of lower resolution and the position data, so that the printing material is swept over in the transport direction with time-modulated radiation points which in each case include a plurality of image points of the higher-resolution printed image.