Abstract: A head loading device includes a print head for ejecting ink from a print position adjacent to a paper sheet to print an image with the ink, and an elevator for moving the print head upward from the print position at the time of non-printing and downward to the print position at the time of printing. The head loading device further includes a three-point support mechanism for supporting, at three points, the print head moved to the print position by the elevator to hold the print head at a preset distance from the paper sheet.

Abstract: A nozzle unit having a plurality of nozzle heads is vertically moved by an elevating mechanism between a printing position where it prints on a printing surface, and a non-printing position above the printing position and separate from the printing position by a predetermined distance. When the nozzle unit moves to the printing position, it is disengaged from the elevating mechanism to be free from it. The nozzle unit which has moved to the printing position is supported by a head support mechanism to be movable in the main scanning direction.

Abstract: A head loading device includes a print head for ejecting ink from a print position adjacent to a paper sheet to print an image with the ink, and an elevator for moving the print head upward from the print position at the time of non-printing and downward to the print position at the time of printing. The head loading device further includes a three-point support mechanism for supporting, at three points, the print head moved to the print position by the elevator to hold the print head at a preset distance from the paper sheet.

Abstract: A nozzle unit is provided with nozzle heads of plural colors. Each nozzle head has a large number of ink-jet nozzles arranged side by side in the direction of main scanning. A head holder supports the nozzle unit in such a manner that the unit can move up and down between the printing position where printing is done on the printing sheet held on a rotating body and the non-printing position located above the printing position where the nozzle heads are maintained. The head holder is provided with a driving control circuit for driving the nozzle heads. The head holder, together with the nozzle unit, are movable vertically.

Abstract: An ink-jet printer includes an ink tank for storing ink, a print head for ejecting the ink supplied from the ink tank to print an image on a paper sheet moved relatively to the print head, an ink-amount sensing section for sensing that ink remaining in the ink tank is decreased to less than a reference amount to generate a sense signal, and a print control circuit for driving the print head such that images are printed on the number of paper sheets ordered by each print job except in a state where the sense signal is generated by the ink-amount sensing section. In particular, the print control circuit is arranged to continue a print job being executed at a time when the sense signal is generated by the ink-amount sensing section.

Abstract: An ink-jet printer, having a print head for jetting ink, an ink supply tube connecting between an ink tank and the print head, an ink supply pump interposing in the ink supply tube, an ink return tube connecting between and the print head and the ink tank, an ink return pump interposing in the ink return tube, a controller for controlling the ink supply pump and the ink return pump to fill the print head with ink in the ink tank, the volume of ink supplied by the ink return pump is greater than the volume of ink returned by the ink return pump in filling mode. Thus a foreign matter in the ink-jet nozzles of the print head can be cleaned by flowing out a foreign matter in the ink-jet nozzles.

Abstract: An ink-jet printer with an ink nozzle purging device includes a valve equipped in a portion of an ink supply pipe extending from a pump to a printing head unit, and an ink urging unit which has a chamber equipped in a portion of the pipe between the valve and the pump, and further has an elastic member disposed in the chamber. The member accumulates an elastic force by a pressure of the ink entering into the chamber while the pump is operated with the valve being closed, and then urges the ink toward the printing head unit when the valve is opened to release the elastic force accumulated in the elastic member.

Abstract: An ink jet printer includes a rotary drum having a peripheral surface for holding a paper sheet, a print head for printing an image on the paper sheet held on the peripheral surface by jetting ink to the paper sheet, and an elevator mechanism for setting the print head to a printing position close to the peripheral surfice at a time of printing and to a non-printing position farther from the peripheral surface than the printing position along a normal line of the peripheral surface at a time of maintenance. Particularly, the elevator mechanism includes a pair of guide rails set parallel to the normal line of the peripheral surface, a slider unit rotatably holding the print head and slidably attached to the guide rails, and a driving section for moving the slider unit up and down.

Abstract: An ink-jet printer comprises a print head for ejecting ink, an ink tank for storing ink to be ejected from the print head, a piping member connected between the ink tank and the print head, a pump mechanism interposed in the piping member to supply ink from the ink tank to the print head, and a control unit for controlling the print head and the pump mechanism to print an image by ejecting ink. In particular, the control unit is constructed to perform a pump drive processing for driving the pump mechanism to discharge all of ink stored in the ink tank in a displacement mode.

Abstract: An image reading apparatus includes a light source for illuminating a document, and a line image CCD for performing photoelectric conversion on the light reflected from the document. Particularly, the image reading apparatus further includes a light shutting device for selectively shutting off the light directed toward the line image CCD, and a processing section for obtaining, as reference black data, the output data of the line image CCD produced in a state where the light directed toward the line image CCD is shut off, for obtaining, as image data of the document, the output data of the line image CCD produced in a state where the light directed toward the line image CCD is not shut off, and for performing shading correction on the image data according to the reference black data.

Abstract: A color image reading apparatus connected to an image data processing apparatus for the supply of a read-in image to the latter, image data processing apparatus comprises a photoelectric converting element for receiving a color manuscript image and for converting this image into electrical image data, a memory for memorizing color correction coefficients, which are used to enable the image data processing apparatus to perform proper color correction, and which, according to the signal from the image data processing apparatus, supplies the electrical image data and the color correction coefficients to the image data processing apparatus.

Abstract: An optical document reader which uses a document keeper to hold a document in place on a document table and which moves an optical unit in the secondary scanning direction along a shaft for optically reading the document. The shaft is supported by a support member which rotates around one end of a support shaft and along the document table. The support member, externally rotated by an adjusting mechanism, is rotatably released by a clutch mechanism. A support member returning mechanism returns the support member to its home position when the member is rotatably released by the clutch mechanism. If the side edge of the document is inclined against that of the document table, the adjusting mechanism rotates the support member to align the optical unit with the document in the secondary scanning direction. When the clutch mechanism rotatably releases the support member afterwards, the support member returning mechanism accurately returns the member to its home position.

Abstract: A lid opening and closing device is disclosed which comprises a plate spring having thereon an engagement portion disposed on the side of a lid and an engagement portion to engage with the engagement portion on the plate spring formed on the side of a housing, whereby the lid can be held opened at a certain angle of opening, a lid pivot for bearing a fulcrum pin on the lid side provided on the housing side for vertical movement while being urged downward, whereby reading of an original is ensured even if the thickness of the original is varied, and flat portions formed on the fulcrum pin and a cut corresponding to the flat portions made in the lid pivot, whereby the fulcrum pin can be detached from the lid pivot, thus performing necessary functions with a simple structure occupying a samll space on the whole.

Abstract: An apparatus for securing a typewriter, includes a locking device for locking an outer case in a closed position and a fastening device for fastening a bottom plate of the case to a mounting base. When opened, the cover permits a portion of the bottom plate to be exposed. The fastening device is brought, from inside the case, into engagement with the bottom plate of the case through the exposed portion of the bottom plate, thereby locking the typewriter to the mounting base. The fastening device for the bottom plate cannot be released unless the locking device is unlocked by a key to open the cover. Accordingly, only a keyholder can unlock the locking device, thus preventing the typewriter from being stolen. Further, since the fastening device is engaged with the bottom plate of the typewriter case, the outer appearance of the typewriter is not degraded.