Abstract: An inkjet recording head includes: a nozzle plate having nozzles arranged in a row; a plurality of pressure generating chambers communicating to the nozzles, the plurality of pressure generating chambers including a first pressure generating chamber and a second pressure generating chamber; a diaphragm formed on one face of the pressure generating chamber; a common ink chamber for supplying the ink to the plurality of pressure generating chambers; and a piezoelectric element for displacing the diaphragm. The first pressure generating chamber is disposed on one side of the nozzles and a second pressure generating chamber is disposed on the other side. The first and second pressure generating chambers are opposed to each other across the nozzles so that the central lines of the first and second pressure generating chambers are almost coincident.
Abstract: A controller outputs a PRE CPF-N signal and a CPF-N signal following the PRE CPF-N signal to an electrophotographic printer. The electrophotographic printer 1 starts a predetermined preparation process in response to the PRE CPF-N signal, and starts irradiation in response to the CPF-N signal. The preparation process completes by the time of when a toner image for a first page formed on a photosensitive drum reaches a transfer point where the toner image is transferred onto a recording medium.
Abstract: A fixing unit that is provided in an image forming device and fixes a toner image transferred to paper is constructed of two belts, belt guides each of which guides the inner periphery of each of the belts, a heating member arranged in one of the belts or heating members arranged in both of the belts, a drive roller for driving the inner periphery of the belt, wherein the belts pinch paper on both surfaces thereof by the belt guides and carry the paper. This construction can realize a fixing unit reduced in size and capable of printing images at high speeds and shortening a rise time that elapses until the fixing unit reaches a fixable temperature.
Abstract: An image detector has an I/V converter for converting, into a voltage output., a current output as a result of a photoelectric element arranged in a traveling direction of an intermediate transfer belt having received light reflected from the intermediate transfer belt and light reflected from toner images formed on the intermediate transfer belt; a peak-hold unit for holding an output voltage into which the light reflected from the intermediate transfer belt has been converted by the I/V converter; and a computation unit for detecting a difference between the output voltage of the peak-hold unit and an output voltage into which the light reflected from the toner images of respective colors has been converted by the I/V converter.
Abstract: An image forming apparatus, having imaging units arranged alternately on both sides of a continuous paper web, is characterized by minimized image misregistration and reduced processing cost. In order to prevent possible color misregistration caused by changes in paper feed path length resulting from the eccentricity of each drive roller, the difference in the eccentric phases of the rollers on the front and back surfaces is controlled, thereby minimizing the difference in changes in paper feed path length.
Abstract: An electrophotographic device with a laser power correction device (and method therefor) includes a laser power detection sensor retractably disposed relative to a laser beam optical path of a laser beam, a laser power adjusting device for controlling laser power of the laser beam based on an output from the laser power detection sensor, and a controller for inserting the laser power detection sensor into the optical path and applying laser power correction when a total laser beam activation time has reached a predetermined time and printing is stopped.
Abstract: A color image forming apparatus includes a developing unit to which a developing bias with an AC component superposed is applied, wherein the DC voltage of the developing bias is adjusted to set the detected density of a solid image at a specified value, the light amount of radiation for exposing an image area having a width of a few dots adjacent to the white paper is adjusted to set the detected density of an image developed under a peripheral electric field at a specified value, and the gradation density curve is regulated by alternately adjusting the DC voltage, the light amount of radiation for exposing the image area having a width of a few dots adjacent to the white paper, and the amplitude of the AC component until the detected density of a mesh point image having an area ratio from 60 to 80% falls within a specified range.
Abstract: An inkjet head having an ink flow path communicated with an ink chamber to an inkjet nozzle and having an orifice plate to which the nozzle is formed. An ink-philic layer is formed on the surface of the ink flow path, and an ink repellent layer is formed on the surface of the orifice plate where the nozzle is formed. The ink-philic layer is made of amorphous silica or inorganic polymer of colloidal silica bonded with a polymer of (SiOR), and the ink repellent layer contains a compound having perfluoropolyether chain and alkoxysilane residue as a terminal.
Abstract: In a scorotron type charging device including a shield case having an opening portion toward a photosensitive body, sawtooth electrodes for generating a corona discharge, and a grid having plural grid wires provided at a predetermined interval from sawtooth electrodes, at least one side surface of shield case is arranged adjacent to one sawtooth electrode, and a relationship between a current It supplied to sawtooth electrodes and current Is flowing through shield case is set to satisfy a conditional expression of ¼?Is/It?½, and an interval between vertexes of sawteeth of the sawtooth electrodes is set to 1 mm or more but 3 mm or less and a relationship between a charged potential Vo of the photosensitive body and a voltage Vg applied to grid is set to satisfy a conditional expression of ?50 V?|Vo|?|Vg|?50 (V).
Abstract: An image forming apparatus includes a toner concentration detector for detecting the toner concentration within a two-component developing unit, a toner supply unit for supplying a toner into the developing unit, a storage unit for sequentially holding and updating a history of a toner supply operation for a certain period of time, and a toner concentration control unit for determining the time of the toner supply operation by the toner supply unit, based on information stored in the storage unit and a difference between an output value of the toner concentration detector and a reference value, and maintaining the toner concentration constant.
Abstract: A multi-color printer (and a method therefor) includes a drum-shaped photosensitive body for black toner, a belt-shaped toner carrier for non-black color toner, a first transferring unit for transferring a color-toner image formed on the belt-shaped toner carrier to a medium, a second transferring unit for transferring a black toner image formed on the drum-shaped photosensitive body, the drum-shaped photosensitive body being disposed near the belt-shaped toner carrier, and a fusing unit for fusing to the medium the black toner image and the color toner image transferred to the paper.
Abstract: A printer system includes a plurality of printing mechanisms, a paper inversion mechanism that inverts a paper between the printing mechanisms, a paper buffer that adjusts a time lag in a synchronous operation, and a controller that receives print data from a host computer and synchronously operates the printing mechanisms to perform double-strike or double-sided printing. Preferably, the controller includes a unit that measures a length of a paper path extended between the printing mechanisms and enters a setup value to perform error recovery printing, an image buffer that stores an amount of data equivalent to a distance between an image transfer point and a fixing point, a pointer function that indicates locations of image data and of data in the image buffer, and a function that employs the pointer function to calculate a range and performs error recovery printing, when a malfunction has occurred and a paper is re-loaded.
Abstract: An ink jet head including nozzles, ink chambers, and an ink channel in fluid communication with each other. A diaphragm defines one portion of each of the ink chambers. Piezoelectric actuators are disposed in confrontation with the diaphragm in a one-to-one correspondence with the ink chambers. A relay member is provided between each piezoelectric actuator and the diaphragm. Each relay member has a first abutment surface and a second abutment surface on opposite sides thereof. Each first abutment surface abuts the diaphragm across a width that extends in the nozzle alignment direction. The width of each first abutment surface is shorter than the width of the corresponding ink chamber. Each second abutment surface is coupled to the corresponding piezoelectric actuator and has a width that extends in the nozzle alignment direction. The width of each second abutment surface is equal to or shorter than the width of the corresponding piezoelectric actuator.
April 18, 2003
Date of Patent:
January 18, 2005
Hitachi Printing Solutions, Ltd.
Jun Nagata, Tomohiko Koda, Yasuhiro Yoshimura
Abstract: A light scanner has a light source 1 of a two-dimensional array consisting of a plurality of light source elements, a coupling lens system 2 for collimating a light flux from the light source 1, a shaping lens system (cylindrical lens 4 and lens 5) for shaping the light flux, light beam deflection means 6 for deflecting and scanning the post-shaped light flux, and a scanning lens system 7 for forming an image of the deflected and scanned light flux on a scanned medium 8. Assuming that the focal length of the coupling lens system 2 is f, a slit 3 for limiting the subscanning direction width as a member for shielding a part of the light flux is placed at a location at a distance of about f from the coupling lens system 2 in an opposite direction to the light source 1.
Abstract: A recording head 200 has a plurality of nozzle orifices aligned in a row extending in a first direction. The recording head 200 is arranged with the nozzle orifices in confrontation with a recording medium P. The recording medium P is moved in a second direction B with respect to the recording head 200. Also, ink droplets ejected from the nozzle orifices are charged to a charged amount that corresponds to deflection amount of the ink droplets. The charged ink droplets are deflected in a direction perpendicular to a main scanning line. The plurality of ink droplets ejected from the plurality of nozzle orifices impinge on the same pixel position or at a nearby position so that it is possible to impinge multiple droplets at the same pixel position or a nearby position. As a result, it is possible to back up broken nozzles and to reduce recording distortion.
Abstract: The subject of the disclosed art is to prevent a short circuit between plural electrodes caused by soldering in the assembling process for a semiconductor laser element. The constitution for improving the subject is as follows. A semiconductor laser device comprises a semiconductor laser chip having a first electrode and a laser sustaining material, in which the laser sustaining material has electrodes and solder layers connected electrically therewith on the surface where the semiconductor laser chip is mounted, the first electrode of the semiconductor laser chip is connected with the solder layer of the laser sustaining material and at least the solder layer of the laser sustaining material extends from at least one end face in the longitudinal direction of an optical resonator of the semiconductor laser chip to the outside of the optical resonator.
Abstract: A transfer member transporting section is disposed so as to bring a tip end of a transfer member into contact with a peripheral face of a transfer rotary member before the tip end of the transfer member enters a nip area. A bias power supply has a polarity inverting function of, during a period from a timing when the tip end of the transfer member is brought into contact with the transfer rotary member by the transfer member transporting section, to that when the tip end of the transfer member enters the nip area, applying a voltage of a polarity which is identical with that of a toner, to the transfer rotary member, and after the tip end of the transfer member enters the nip area, applying a voltage of a polarity which is opposite to that of the toner, to the transfer rotary member.
Abstract: A two-dimensional beam writing position detecting device for providing an optical system for scanning on a photoconductor by laser beams emitted from a semiconductor laser to form an electrostatic latent image and arranging a plurality of the laser beams in two dimensions and slantingly scanning each the laser beam for forming the electrostatic latent image on the photoconductor at a predetermined angle and detecting the laser beams for determining the first writing position on the photoconductor of the laser beams is characterized in that a longitudinal direction of a beam light receiving surface of the detecting device 1 inclines at the substantially same angle as the slant scanning angle with respect to the perpendicular of a scanning direction of the plural beams.
Abstract: An ink jet head includes: a pressure chamber that stores an ink and has an orifice; a filter plate including a through hole portion and a filter portion, the through hold portion disposed separately from the filter portion with a certain gap; a supply unit that supplies the ink through the filter portion to the pressure chamber; and a jetting unit that jets ink droplets through the orifice from the pressure chamber. The filter portion is formed to have a first aperture ratio. At least one through hole is formed on the through hole potion so that the filter portion has a second aperture ratio. The first aperture ratio is smaller than the second aperture ratio.
Abstract: An exposure device for an electrophotographic apparatus including one or more laser light sources which expose an image carrier in accordance with a print information signal supplied from an external information processing apparatus, a resolution switching lens, and a switching unit to switch over a low resolution and a high resolution by inserting and extracting the resolution switching lens into and from a laser optical path. Preferably, a light emission time of each of the laser light sources with respect to the print information signal is changeable.