An apparatus and method of conveying parts underneath an array of inkjet printheads in such a way as to minimize print defects caused by variation in motion. The conveyor is composed of a series of rigid conveyor track segments that are forced to move in a precise straight line due to a combination of accurate ball bearing wheel assemblies and precision machine guideways that are incorporated into the conveying system.

A device is provided for feeding sheets to a sheet-processing machine having at least one processing mechanism. A feeder head is provided for cyclically separating the sheets from a pile of such sheets and has transporting suckers for transporting the sheets to a belt table. The belt table has at least one revolving transport belt which is guided over at least two feed rollers. A first drive is assigned to at least one feed roller and a sheet flap, which is connected to a pivotally mounted shaft, is provided between the transporting suckers and the at least one transport belt. A second drive is assigned to the shaft, for pivoting that shaft. A sheet arrival sensor, which is arranged between the belt table and the processing mechanism, generates first signals representing the arrival of the sheets for a sequence of sheets. A clock generator generates second signals representing the angular position of the at least one processing mechanism, and has a controller, which controls the first drive as a function of the second signals and which controls the second drive as a function of the first and second signals.

A vacuum belt conveyor sequentially delivers sheet articles to a digital printer. The sheets are held in position by vacuum on the underside of the sheets through apertures in the belts and covered by the sheets. A plurality of independent plenums on the underside of the belt have chambers respectively communicating with rows of apertures extending along the belt. Vacuum is selectively applied from a manifold only to the plenum chambers that supply apertures that are covered by the sheets so that the ink from the printer will not be directed from its intended position on the sheet by vacuum from adjacent uncovered belt apertures. The sheets are fed to the conveyor in synchronism with the conveyor speed by a timed feeder so that the sheets are carried by the conveyor with a predetermined gap between the sheets and no belt apertures in the gap. A sensor counts the apertures in the belt and activates the feeder at predetermined time intervals.

In an example, a media conveyor includes a media support platform having a suction hole, and a valve to selectively close the suction hole. A valve actuator to actuate the valve includes an air tube having an air inlet and a seal to selectively seal the air inlet.

In one example, a media support with a continuous belt rotatable and suction cups lengthwise along the belt and in lines laterally across the belt to hold down a sheet of print media as the sheet is moved through a hold down area, a vacuum pump to supply vacuum to the suction cups. The vacuum control system is configured to close a supply of vacuum to all of the suction cups in the hold down area and then open the supply of vacuum sequentially to each of multiple lines of suction cups as each line enters the hold down area and then close the supply of vacuum sequentially to each of the multiple lines of suction cups as each line leaves the hold down area until all of the suction cups in the hold down area are closed.

In one example, a media support includes a continuous loop belt and multiple suction cups arranged along the outer perimeter of the belt. Each suction cup has a port aligned with a hole in the belt so that air may be evacuated from the suction cup when connected to a vacuum source.

In an example, there is provided a method including: receiving, at a processor, data specifying the shape of a blank to form a folded article; and determining, using the processor, based on the received data, a suction array layout to hold the blank against a media support, wherein the suction array layout conforms to the shape of the blank.

A sheet folding apparatus includes a sheet folding unit disposed to fold a sheet and a conveyance unit disposed to feed the sheet to the sheet folding unit in a feed direction orthogonal to a fold direction of the sheet folding unit while correcting a skew of the sheet. The conveyance unit includes an elongated reference guide, a conveyance mechanism disposed to convey the sheet in the feed direction while exerting a force on the sheet toward the reference guide, an adjustment mechanism disposed to adjust an inclination of the reference guide with respect to the feed direction. The apparatus further includes an input unit through which a user inputs a folding misalignment amount of the sheet folded by the sheet folding unit. The inclination of the reference guide is corrected by the adjustment mechanism based on at least the folding misalignment amount inputted through the input unit.

A device is provided for feeding sheets to a sheet-processing machine having at least one processing mechanism. A feeder head is provided for cyclically separating the sheets from a pile of such sheets and has transporting suckers for transporting the sheets to a belt table. The belt table has at least one revolving transport belt which is guided over at least two feed rollers. A first drive is assigned to at least one feed roller and a sheet flap, which is connected to a pivotally mounted shaft, is provided between the transporting suckers and the at least one transport belt. A second drive is assigned to the shaft, for pivoting that shaft. A sheet arrival sensor, which is arranged between the belt table and the processing mechanism, generates first signals representing the arrival of the sheets for a sequence of sheets. A clock generator generates second signals representing the angular position of the at least one processing mechanism, and has a controller, which controls the first drive as a function of the second signals and which controls the second drive as a function of the first and second signals.

A sheet conveyance apparatus includes a control unit (120) that controls driving of a belt drive mechanism (4). The control unit (120) performs control such that the sheet is conveyed from the sheet accumulation area if (a) it is determined that the number of sheets currently accumulated in the sheet accumulation area is two or greater, while the sheet is not conveyed from the sheet accumulation area if (b) it is determined that the number of sheets currently accumulated in the sheet accumulation area is one.