Abstract: The present invention is directed to a piezoelectric vibrator unit including an elastic plate made of piezoelectric material having at least one curved portion. The piezoelectric vibrator unit also includes at least one common electrode and a discrete electrode which are formed on opposite sides of the elastic plate. The application of an electric field applied between the electrodes 3 and 4 causes the extension or contraction of the curved portion of the plate.

Abstract: Driving signal generating member for generating a first signal for drawing as meniscus at a nozzle aperture by smaller force as ambient temperature rises, a second signal for contracting a pressure generating chamber and ejecting an ink droplet and a third signal for restoring the contracted pressure generating chamber after an ink droplet is ejected by larger drawing force as ambient temperature rises is provided, speed at which the meniscus is moved toward the nozzle aperture is prevented from decreasing by setting force for drawing the meniscus before an ink droplet is ejected when temperature falls to a large value and the delay of filling the pressure generating chamber with ink is prevented by setting force for drawing the meniscus after an ink droplet is ejected to a small value and damping the residual vibration of the meniscus utilizing attenuation by increasing the viscosity of ink.

Abstract: The structure of the present invention effectively prevents banding and enables high-quality printing in a printer which carries out secondary scans in the interlacing manner and thereby prints an image. The printer of the present invention has a print head with a plurality of nozzle arrays formed thereon. Each nozzle array includes a plurality of nozzles arranged at predetermined pitches in the secondary scanning direction. The printer records an image by the interlacing method using part of the nozzles in each nozzle array. The nozzle block in the nozzle array used for formation of dots is changed in every primary scan, and the amount of feed in secondary scan is varied with the change of the nozzle block. Both the nozzle block and the amount of secondary scan are periodically changed in preset sequences. The variation in amount of secondary scan reduces the banding due to the accumulated errors in secondary scans.

Abstract: An ink jet printing apparatus has an ink jet print head mounted on a carriage reciprocally movable relative to a print medium, an ink cartridge for supplying ink to the ink jet print head, a print control apparatus for outputting a drive signal to the ink jet print head in accordance with print data, flushing control apparatus for discharging ink, not contributing to print, in order to secure a normal ink discharge from the ink jet print head, and a control data storing apparatus for storing control data for the flushing control apparatus. A control mode of either of the print control apparatus and the head maintenance control apparatus may be altered by data from an ink characteristic data storing apparatus, provided on the ink cartridge, for storing control data based on the nature of ink.

Abstract: An actuator for an ink jet printer includes: an ink tank comprising a thick substrate having a cavity structure and a vibrating plate covering a cavity; and a piezoelectric/electrostrictive working portion comprising an upper electrode layer, a lower electrode layer, and a piezoelectric/electrostrictive layer between the electrode layers, the piezoelectric/electrostrictive working portion being disposed on the ink tank so that the lower electrode layer contacts with the vibrating plate. The upper electrode is trimmed only in the portion where the piezoelectric/electro-strictive layer covers the vibrating plate so as to control an effective electrode area and adjust an ink jet volume to be appropriate. The upper electrode layer is trimmed with the piezoelectric/electrostrictive layer covering the vibrating plate at least near the portion to be trimmed of the upper electrode layer so as to control an effective electrode area and adjust an ink jet volume.

Abstract: A filter chamber having a portion inclined in relation to the horizontal direction is formed between an ink supply channel having one end communicating with an ink cartridge and a throughhole communicating with an ink-jet recording head, and a filter plate is placed in the filter chamber so as to diagonally traverse it, so that ink is allowed to pass through the whole surface of the filter plate.

Abstract: An ink supply device includes an ink container connected to an air communication port through a porous member. The ink container is maintained at a negative pressure equivalent to the capillary force of the ink penetrated into the porous member. Since the ink container is in communication with the air through a wide area of the porous member, the ink container can be maintained at a constant negative pressure regardless of the quantity of ink consumed by the recording head.

Abstract: An ink cartridge and an ink cartridge identifying apparatus are provided which reliably allow only standard, proper ink cartridges to be loaded. An ink cartridge to be loaded into a printer is provided which has a predetermined projected and recessed pattern portion formed on an outer surface thereof and which has a first electrode portion arranged on the projected and recessed pattern portion. The first electrode portion is positioned to be selectively engageable with a second electrode portion, which is arranged on a pattern matching portion which is fixed to a press rod arranged on the printer main body. First and second electrode portions are arranged on the projected and recessed pattern portion and the pattern matching portion to be selectively engageable, and an identification signal is generated when matching first and second electrode portions are engaged. The projected and recessed pattern portion and the pattern matching portion may be shaped into characters/symbols, graphics, or the like.

Abstract: A print head 2 has multiple nozzle groups 2a, 2b spaced apart in the sub-scanning direction by a prescribed inter-group distance pn.sub.i. Each nozzle group 2a, 2b has multiple nozzles aligned in the sub-scanning direction at a nozzle pitch k. In a first printing scheme in which the nozzle groups record different raster lines, the inter-group distance pn.sub.i is set to a value different from the nozzle pitch k. Since the nozzle pitch k need be secured only within the nozzle groups 2a, 2b individually, a print head 2 with many nozzles can be readily obtained. Interlace printing can be effected by selecting the total number of nozzles N, the number of nozzle groups M, the number of scans S and the nozzle pitch k to make N/(M.multidot.S) and k/M relatively prime and effecting sub-scanning at a constant pitch of N/S dots. In a second printing scheme in which multiple nozzle groups record every raster line, the selection is made to make N/(M.multidot.

Abstract: An ink cartridge using an ink bag capable of being mounted in a carriage, comprising: a container having a body unit 1 and a cover unit 3 to form an internal space therebetween, at least one of said body unit and said cover unit being provided with valves 10 and 11 openable for communication between the internal space of said container and the atmosphere according to pressure change in said container; a cap 21 connecting with an ink supply needle of a recording head mounted in a carriage; and an ink bag, the periphery of which is held by said cover unit 3 and body unit 1. A constant negative pressure can be maintained by valves 10 and 11, and the periphery of ink bag 20 is held by body unit 1 and cover unit 3, ensuring as constant a shape as possible and preventing pressure changes caused by oscillation.

Abstract: A piston is slidably arranged in an ink chamber designed to communicate with a recording head through an ink passage. The pressure inside the ink chamber is kept to a predetermined negative pressure at all times by taking advantage of the tare of the piston. As a result of this construction, leakage of the ink from a recording head can be prevented independently of the ink tank mounting position or temperature fluctuations.

Abstract: An ink jet type recording head composed of a plurality of head units and having a large number of nozzles without greatly increasing the width of the recording head. Outer walls 1a, 1b of a spacer 1 of the heat unit are inclined at an angle .theta. with respect to the arrangement lines A--A, B--B of pressure generating chambers 2, 3. A plurality of head units (e.g., 40, 41) are arranged so that end surfaces of the head units in the arrangement direction of the pressure generating chambers 2, 3 are adjacent to each other. The head units are fixed to a base board 28 such that they are shifted in a direction roughly perpendicular to the arrangement direction of then pressure generating chambers 2, 3 and so that an interval between the pressure generating chambers 2, 3 of the adjacent head units is the same as the pitch between the pressure generating chambers 2, 3 on each individual head unit.

Abstract: An ink jet recording apparatus comprising: an ink jet recording head for sucking an ink into a pressure chamber and jetting an ink droplet from a nozzle opening by expanding and contracting the pressure chamber by a piezoelectric vibration element; the pressure chamber being formed of a nozzle plate and a vibration plate; and a signal generating device for generating signals. The signals includes a first signal for contracting the piezoelectric vibration element at a predetermined speed to suck the ink into the pressure chamber, a second signal for starting an extension process of the piezoelectric vibration element to splash the ink droplet from the nozzle opening by contracting the pressure chamber, a third signal for interrupting the extension process of the piezoelectric vibration element at least once while the extension process is still being performed and a fourth signal for resuming the extension process of the piezoelectric vibration element again after a predetermined period has elapsed.