Abstract: An apparatus, method and computer program for controlling the tension in roll-based print media. The apparatus comprises: an encoder arranged to detect an angular displacement of a roll of print media; a processing unit arranged to determine the radius of the roll of print media based on the detected angular displacement of the roll of print media; a motor arranged to apply torque to the roll of print media to create tension in the print media; and a controller arranged to control the torque applied by the motor based on the determined radius of the roll of print media.

Abstract: A fluid ejection device includes a fluid-ejection mechanism, a scanning carriage, and a service station. The fluid-ejection mechanism is capable of ejecting fluid onto media. The scanning carriage is that on which the fluid-ejection mechanism moves while ejecting fluid onto the media. The service station is that to which the fluid-ejection mechanism is movable by the scanning carriage, and that at which fluid aerosol from the fluid-ejection mechanism is extracted by a vacuum via an airflow path from the fluid-ejection mechanism temporarily fluidically coupled to the vacuum during servicing of the fluid-ejection mechanism.

Abstract: An aerosol extraction system for a fluid-ejection device is disclosed that includes a print zone, a servicing zone, a vacuum, and a switching mechanism. The print zone is that in which a print head of the fluid-ejection device ejects fluid onto media to form images thereon. The servicing zone is that in which the print head is serviced. The vacuum is fluidically connectable to both the print zone and the servicing zone. The switching mechanism is to fluidically connect and disconnect at least one of the print zone and the servicing zone to the vacuum.

Abstract: An aerosol extraction system for a fluid-ejection device is disclosed that includes a print zone, a servicing zone, a vacuum, and a switching mechanism. The print zone is that in which a print head of the fluid-ejection device ejects fluid onto media to form images thereon. The servicing zone is that in which the print head is serviced. The vacuum is fluidically connectable to both the print zone and the servicing zone. The switching mechanism is to fluidically connect and disconnect at least one of the print zone and the servicing zone to the vacuum.

Abstract: A fluid ejection device includes a fluid-ejection mechanism, a scanning carriage, and a service station. The fluid-ejection mechanism is capable of ejecting fluid onto media. The scanning carriage is that on which the fluid-ejection mechanism moves while ejecting fluid onto the media. The service station is that to which the fluid-ejection mechanism is movable by the scanning carriage, and that at which fluid aerosol from the fluid-ejection mechanism is extracted by a vacuum via an airflow path from the fluid-ejection mechanism temporarily fluidically coupled to the vacuum during servicing of the fluid-ejection mechanism.

Abstract: A media holddown device a plastics vacuum guide attached to a sheet metal vacuum beam, the guide includes vacuum chambers in communication with the beam through openings to control the negative pressures applied to media of varying widths by a fan. Dividing walls are provided between the chambers to maintain the value of the negative pressure larger than a predetermined value, especially for media with conventional widths. An intermediate wall divides the guide into front and rear chambers to increase the control of media leading edges. The number, size and pattern of arrangement of openings are selected to produce desired air flow characteristics.

Abstract: A fluid ejection device includes a first edge and an electrical interconnect disposed along the first edge. The fluid ejection device also includes a second edge opposite the first edge. Multiple dies are disposed on the fluid ejection device such that a pair of dies are disposed adjacent the second edge and another die is disposed adjacent the first edge. Each die contains at least one drop-ejecting element. Multiple fluid ejection devices are arranged such that the second edges of the fluid ejection devices are adjacent one another.

Abstract: A hard copy device having a carriage arranged to support a printhead and to reciprocate across a scan axis, the device being arranged to determine the position of at least a part of the printhead along the scan axis, compensating for carriage rotation about the an axis orthogonal to the scan axis, by interpolating or extrapolating from carriage position information derived from first and second codestrips traversing the scan axis and spaced apart in a direction orthogonal to the scan axis.

Abstract: A fluid ejection device includes a first edge and an electrical interconnect disposed along the first edge. The fluid ejection device also includes a second edge opposite the first edge. Multiple dies are disposed on the fluid ejection device such that a pair of dies are disposed adjacent the second edge and another die is disposed adjacent the first edge. Each die contains at least one drop-ejecting element. Multiple fluid ejection devices are arranged such that the second edges of the fluid ejection devices are adjacent one another.

Abstract: The apparatus is provided with a holddown device for a medium lying on a platen, said device comprising first cockle-control means which in a medium output zone downstream of the print zone control an expansion of the medium to be in the form of a wave defined by a plurality of bubbles and substantially adapted in frequency to a ridged surface of the supporting platen; the holddown device may comprise second cockle-control means which control an expansion of the medium in the print zone to be in the form of at least two parallel waves defined by a plurality of bubbles and alternated such that a downward bubble of one of the waves is adjacent to an upward bubble, or no bubble, of an adjacent wave in the direction (Y) of advance of the medium. The effects of cockle are improved without tensioning the medium downstream from the printing zone, and improving vertical banding.

Abstract: A scanning device such as a printer has a trapezoidal carriage support beam which permits a compact juxtaposition of the carriage slider rod, the printhead, a drive belt and an encoder device. A second slider mounting for the printer carriage includes a bushing incorporating a part-spherical portion and an arm which engage with corresponding parts of the carriage.

Abstract: A carriage slider rod is mounted on a steel beam by means of brass support elements. The support elements are first riveted to the beam and then have precisely aligned V-shape grooves machined therein to provide accurate location for the slider rod. The slider rod is screwed to the beam using central bores passing through the support elements. To fix the support elements to the beam, they are first located in respective apertures and then deformed by a clenching tool, one jaw of which passes through an adjacent aperture in the bottom wall of the beam.

Abstract: The apparatus is provided with a holddown device for a medium lying on a platen, said device comprising first cockle-control means which in a medium output zone downstream of the print zone control an expansion of the medium to be in the form of a wave defined by a plurality of bubbles and substantially adapted in frequency to a ridged surface of the supporting platen; the holddown device may comprise second cockle-control means which control an expansion of the medium in the print zone to be in the form of at least two parallel waves defined by a plurality of bubbles and alternated such that a downward bubble of one of the waves is adjacent to an upward bubble, or no bubble, of an adjacent wave in the direction (Y) of advance of the medium.

Abstract: The apparatus is provided with a holddown device for a medium lying on a platen, said device comprising first cockle-control means which in a medium output zone downstream of the print zone control an expansion of the medium to be in the form of a wave defined by a plurality of bubbles and substantially adapted in frequency to a ridged surface of the supporting platen; the holddown device may comprise second cockle-control means which control an expansion of the medium in the print zone to be in the form of at least two parallel waves defined by a plurality of bubbles and alternated such that a downward bubble of one of the waves is adjacent to an upward bubble, or no bubble, of an adjacent wave in the direction (Y) of advance of the medium. The effects of cockle are improved without tensioning the medium downstream from the printing zone, and improving vertical banding.

Abstract: A pen carriage for use in an inkjet printer of the type which includes a moveable scanning carriage, the carriage having at least one stall for reception of an inkjet pen having an upwardly directed fluid inlet which can be slidably connected to establish fluid communication of an inkjet pen on the carriage with an offboard fluid supply remote from the pen and a fluid delivery tube for connecting the supply to the pen. The carriage includes a base and a pen cover pivotally attached to the base, the tube having a length extending between pivotal connections of the cover to said base generally parallel to and radially spaced from the axis of pivotal connection of the cover to the base to permit and confine all twisting of the tube to the length between the connections. The cover also includes a fluid delivery passageway having a downwardly directed fluid delivery outlet opening toward and connected in fluid delivery relationship with the upwardly directed pen inlet when the cover is latched in closed position.

Abstract: A media holddown device a plastics vacuum guide attached to a sheet metal vacuum beam, the guide includes vacuum chambers in communication with the beam through openings to control the negative pressures applied to media of varying widths by a fan. Dividing walls are provided between the chambers to maintain the value of the negative pressure larger than a predetermined value, especially for media with conventional widths. An intermediate wall divides the guide into front and rear chambers to increase the control of media leading edges. The number, size and pattern of arrangement of openings are selected to produce desired air flow characteristics.

Abstract: A modular printer chassis, particularly for large scale printers, includes a lower media module which provides a rigid platen media support surface connected to an upper scanning carriage support module by a plurality of fasteners which are tightened at the time of assembly to thereafter permanently hold the modules, which are accurately positioned with the aid of a gauge at the time of assembly, in place so that the accurate inkjet printhead to media spacing in the print zone is maintained.

Abstract: The apparatus is provided with a holddown device for a medium lying on a platen, said device comprising first cockle-control means which in a medium output zone downstream of the print zone control an expansion of the medium to be in the form of a wave defined by a plurality of bubbles and substantially adapted in frequency to a ridged surface of the supporting platen; the holddown device may comprise second cockle-control means which control an expansion of the medium in the print zone to be in the form of at least two parallel waves defined by a plurality of bubbles and alternated such that a downward bubble of one of the waves is adjacent to an upward bubble, or no bubble, of an adjacent wave in the direction (Y) of advance of the medium.

Abstract: A scanning device such as a printer has a trapezoidal carriage support beam which permits a compact juxtaposition of the carriage slider rod, the printhead, a drive belt and an encoder device. A second slider mounting for the printer carriage includes a bushing incorporating a part-spherical portion and an arm which engage with corresponding parts of the carriage.

Abstract: A carriage slider rod is mounted on a steel beam by means of brass support elements. The support elements are first riveted to the beam and then have precisely aligned V-shape grooves machined therein to provide accurate location for the slider rod. The slider rod is screwed to the beam using central bores passing through the support elements. To fix the support elements to the beam, they are first located in respective apertures and then deformed by a clenching tool, one jaw of which passes through an adjacent aperture in the bottom wall of the beam.