Abstract: In bidirectional printing, ink-drop time-of-flight effects undesirably operate in opposite senses, during operation in the two different printing directions respectively, to offset the actually printed ink position in opposite directions from any nominal ink-firing point. When a common firing point is used for marks that should be aligned, during bidirectional scanning, the two resulting sets of image features are misaligned. To compensate for this adverse phenomenon, the firing points, in the two directions respectively, are made to bracket each common, desired mark location; the bidirectionally flying drops thus "lead" or approach each desired common mark location from opposite directions and can be made to align precisely. This can be done by addressing each position based on an earlier-arriving encoder-signal pulse and passing the signal through a delay line--during pen movement in just one of the two directions.

Abstract: An ink jet printer in which hardened ink is readily and reliably removed from a nozzle plate. The ink jet printer includes a print head having a plural number of nozzle openings arrayed in the width direction of a recording paper, a head drive circuit for selectively outputting a first signal to cause a stream of ink droplets at a speed suitable for print and a second signal to cause ink to ooze through each nozzle opening, and a cleaning device with a rubbing function and which is usually positioned in a nonprinting region, but is movable in the longitudinal direction of the print head and with respect to a nozzle plate. In a cleaning mode, the cleaning device is operated while oozing ink from the nozzle openings. The hardened ink on the nozzle plate is dissolved by the oozing ink, and then removed therefrom through the rubbing and wiping operations of the cleaning device.

Abstract: The suction and covering device (4, 4a, 4b) described has flexible rubber insert caps (41, 41a) with a fluid-absorbing lining (42, 42a), for suctioning ink from the print heads (80) and for sealing the print heads hermetically. Each rubber insert cap (41, 41a) is associated with a duct (403, 415, 463) for pressure compensation in the rubber insert cap and with an aspiration duct (401, 400) for removing ink. In order to ensure controlled removal of ink from each rubber insert cap (41, 41a), each suction duct (401, 400) has a valve device (48, 420), wherein the valve device may be a slit-type valve or a capillary filter. A controllable closure or a diaphragm in the pressure-compensation duct prevents air from being forced into the jet nozzle apertures when coupling up.

Abstract: An apparatus and method for automatically clamping film material onto the recording drum of a reproduction device and for releasing the film material exposed by a recording element from the recording drum. The apparatus has a roll film cassette introducible into a light tight portion of the reproduction device. Conveyor and guide surfaces are provided between the roll film cassette and the recording drum. Film conveying means is provided for conveying the film web situated in the roll film cassette to the recording drum. A film cutting means is provided for the separation of film sheets. A film length measuring means, a pressure means having a lowerable pressure roller for the film sheets, a positioning drive for turning the recording drum into a start of clamping, start of exposure and start of release position, and a lift-off means having a lowerable lift-off finger for peeling the exposed film sheets from the recording drum are all provided. The film sheets are fixed on the recording drum by vacuum.

Abstract: The device for transporting recording media (100), used especially in a fuser station of a printer or photocopier, comprises a counter-roll (201) and a feed roll (205), mounted movably relative to the counter-roll (201), between which rolls the recording medium (100) is transported by friction. Furthermore, a guide bar (214) is arranged in the manner of a balance beam with spacing parallel to the feed roll (205) and so as to be pivotable about an axis of rotation (216) relative to the feed roll (205). In order to press the feed roll (205) against the counter-roll in a force-compensating manner, as required, spring elements (218) are arranged on the guide bar (214) on both sides of the axis of rotation and are coupled to bearing elements (206) of the feed roll (205). The guide bar can be deflected via an adjusting motor (224) for controlling the position of the recording medium (100) between the rolls (201, 205).

Abstract: In an electro-photographic device for printing photographic images by fixing heated toner on printing paper. The electro-photographic device has a cover which is opened by an operator during maintenance and error recovery operations. Since the device has a paper sending unit provided on both the main body and the cover of the device, the paper sending unit has to be driven to recover synchronization after the operation is completed. On the other hand, the device cuts off power to the fixation unit for safety reasons during the operation which causes the fixation unit to cool. The present device is characterized in that the device starts the recovery procedure after the temperature of the fixation unit reaches an optimal point above the melting point of the toner so that the fixation unit is not damaged by solid toner.

Abstract: An ink jet printer, including a gap regulating member that can forward a recording medium correctly by causing the recording medium to approach a recording head as closely as possible involving minimal parts. An upper surface of the gap regulating member serves as a surface for guiding travel of an ink jet head and a lower surface thereof serves as a surface for guiding a recording medium. The gap regulating member is disposed adjacent to a start end of an upwardly rotating region on a sheet feed roller in such a manner that the gap regulating member intersects a circumferential surface of the sheet feed roller at a small angle.

Abstract: An ink-jet pen for storing at below-ambient pressure has an orifice formed therein for providing air bubbles to prevent the back pressure from rising above a level that would cause malfunction of the pen. The amount of air drawn into the reservoir is restricted by the reservoir ink that covers the orifice whenever the pen is in an upright position. The valve operates to occlude the orifice whenever the pen is moved into a position, such as inverted, where the reservoir ink no longer covers the orifice. The occlusion of the orifice prevents the unrestricted flow of ambient air into the reservoir that would otherwise eliminate the required back pressure in the reservoir. The valve includes a sealing liquid selected so that the liquid occludes a passage between the orifice and ambient air without flowing through that passage.

Abstract: An apparatus to detect sheet misfeeds and jams in an electrophotographic printing machine by measuring the tangential reaction force of a sheet entering the nip between two drive rolls and comparing the measured force with preprogrammed parameters within the machine controller. In the event the force measured does not fall within the programmed parameters, the drive motor controller and machine controller can take appropriate corrective action to display an error message, lessen sheet damage and prevent machine damage. A force library can be compiled to predict drive roll wear and failure so as to allow preventative measures to be taken.

Abstract: A toner supplement control device incorporated in an image forming apparatus for executing the supplement of a fresh toner to a developing unit only when a particular document image process mode is under way. The particular process mode is any one of a document image receive mode, a document image record mode, a document image copy mode, a supervisory report record mode, etc. In the event of initialization of the apparatus, during ordinary recording operation, and when a cleaner and toner magazine (CTM) is to be replaced, whether or not a fresh toner is present in the CTM is determined on the basis of the condition of a fresh toner existing in a developing unit.

Abstract: The invention is directed to a device for clamping sheet-shaped film material onto the recording drum of a reproduction device and is directed to the operation of this device. The recording drum comprises axially proceeding suction-hole rows for the vacuum-fixing of the recording material. Suction channels, each of which connects the suction holes of a suction hole row to one another, proceed in the wall of the recording drum. A vacuum distributor controllable by the rotational movement of the recording drum is arranged in the recording drum, this controllable vacuum distributor selectively bringing the individual suction channels, the corresponding suction hole rows into communication with a stationary vacuum pump. The vacuum distributor is controllable such that that suction hole row on which the starting region of the recording material lies is first charged with vacuum during the clamping event.

Abstract: In a paper sheet conveying operation for a plotter, a roller paper sheet 29 supported on a feeding roller 35 is slackened by way of rotation of the feeding roller. The suspended portion of the paper sheet is pulled up onto the platen 34 due to rotation of the drive roller 10. Then, the suspended portion of the paper sheet 29 passes through a pair of tension rollers 27 and 28 and receives weak tension from the tension rollers 27 and 28, thus preventing the paper sheet from snaking. When the tension rollers are not placed correctly in parallel to the Y-rail of the plotter, the distances of the left and right edges of the paper sheet from the tension rollers to the drive roller become unequal. Consequently, unequal tensions are generated in the opposing edges of the paper sheet when it passes between the tension rollers 27 and 28, thereby causing a discrepancy in the conveyance of the paper sheet 29.

Abstract: An imaging system having a source of light movable with respect to a writing element and projectable thereon to generate an image, a focusing device is provided for focusing a light source which generates a beam of light of a wavelength selected to be actinic with respect to the writing element. At least a portion of the beam of light is absorbed by the writing element. The apparatus includes an imaging drum for holding donor sheets and receiver sheets in registration on the drum. A registration device including a non-reflective indicia on the surface of the drum facilitates the proper registration of the donor and receiver sheets.

Abstract: A thin film thermal ink jet printhead having a compound ink feed slot that includes a trench in the top surface of a silicon substrate and a plurality of slots extending from the bottom surface of the silicon substrate to the trench. A plurality of patterned thin film layers are disposed on the top surface of the silicon substrate apart from the trench, and a patterned ink barrier layer is disposed over the plurality of patterned thin film layers. The patterned ink barrier layer includes an opening generally in alignment with the elongated trench, and a plurality of openings that form ink containing chambers which are adjacent to the trench and in communication with the opening that is generally in alignment with the elongated trench. Ink is conveyed from outside the substrate through the slots and trench, and into the ink containing chambers.

Abstract: A printer with a sorter unit allows printed recording sheets to be sorted to a single tray selected from a plurality of trays by a recording sheet guide mechanism that pivots around a shaft. Thus, the printer can sort the printed sheets by page, by user, or discharge the printed sheets paginated or with the printed side facing upward. The sorter trays includes a first detection lever that is rotated by the weight of recording sheets and a second detection lever that rotates in association with the first detection lever. A lever detector is provided on the sorter guide to detect the movement of the second detection lever. The sorter or guide is also provided with a sheet detection lever to detect a jam in the sorter guide.

Abstract: A contact charger includes a photoreceptor having a photosensitive layer formed on a surface of an electrically conductive drum base and a fixed coil connected to the drum base and ground. The contact charger charges the photosensitive layer by making a charge roller in contact with the photosensitive layer while being applied thereto DC voltage from a power supply. With this arrangement, in the case where a pin hole exists on the photosensitive layer, there may have a continuity between the charge roller and the drum base which may results in a sudden increase in current flowing between the drum base and ground. When this happens, however, since self-induced electromotive force, having a direction opposite to the electromotive force of the power supply, is generated by the fixed coil in response to a sudden increase in current, excessive current will not flow between the drum base and ground, thereby eliminating the possibility of a large drop in voltage of the power supply.

Abstract: In an image forming apparatus according to the present invention, when a resist sensor detects an error or a malfunction in the forward feeding of the document, a main processor continues the copying operation for the document until a preset number of copies for the document are completed. After the completion of copying, the error is corrected and then the document is discharged. The image forming apparatus is simple in operation, and enables the correct number of copies to be made without complicated control.

Abstract: A seal-forming device for a replenishment toner receiving aperture of a development apparatus includes a resilient member mounted to the development apparatus and around the aperture. The seal-forming device also includes a woven fabric that is mounted to the resilient member and to a part of the development apparatus. The woven fabric has warp and filling fibers. The warp fibers are larger than the filling fibers and are mounted to lie in the direction of loading and unloading a replenishment toner container relative to the seal-forming device.

Abstract: An image forming apparatus according to the invention includes a document transporting device for transporting a plurality of documents set on a tray one by one to a platen, copying mode selecting keys for selecting a first copying mode for forming images from the plurality of documents under first copying conditions and a second copying mode for forming an image from a particular one of the documents under second copying conditions, and a control device for executing the image forming operation under the copying conditions of the copy mode selected by the copy mode selecting key.

Abstract: An image forming apparatus in which toner images are transferred using a combination of heat and pressure to a receiving sheet includes a transfer drum with a vacuum holding means for the receiving sheet. To prevent a loss of nip pressure over vacuum holes, the drum is formed of a metallic core with a slot running generally parallel to the core's axis of rotation. A thin metallic sheet is positioned around the core, which sheet has very thin slots running across the slot in the core. A vacuum is applied to the core slot which communicates through the sheet slots to hold a receiving sheet to the outside surface of the metallic sheet.