Toshiba Tec Kabushiki Kaisha

Takahisa Ikeda

Megumi Shimizu

Atsushi Kubota

Hidehiro Watanabe

Isao Suzuki

Masashi Shimosato

Hideaki Nishida

Minoru Koyata

Kouichi Adachi

Yoshiro Eto

Takashi Kukuchi

An inkjet head includes a plurality of nozzles, a plurality of pressure chambers arranged along a first direction, each of which extends in a second direction crossing the first direction, communicates with one of the nozzles, and has a first end through which ink is supplied and a second end through which ink is recycled, a plurality of ink inlets configured on a side of the first ends of the pressure chambers through which ink is supplied to the pressure chambers, and a plurality of ink outlets configured on a side of the second ends of the pressure chambers through which ink is recycled from the pressure chambers. A flow rate of the ink flowing from a ink inlet to an ink outlet through pressure chambers that are at the ends along the arrangement positions of the pressure chambers is higher than a flow rate of the ink flowing from an ink inlet to an ink outlet through pressure chambers that are at the center along the arrangement positions of the pressure chambers.

Inkjet head and inkjet recording apparatus

An air removing device is connected to a tank to contain ink through a first supply tube, and an ink-jet head is connected to the air removing device through a second supply tube. The first supply tube and ink-jet head are heated and controlled. Air dissolved in ink is sucked out through a hollow fiber membrane provided in a housing by operating a vacuum pump by supplying ink to the hollow fiber membrane while heating and controlling atmosphere in the housing. Thus, air dissolved in ink is removed, and ink heated to a temperature suitable for ejection is supplied to the ink-jet head.

Ink-jet recording apparatus, method of removing air of ink-jet recording apparatus and removing air device

An ink-jet head includes a nozzle array including plural nozzles. The nozzle array has a first nozzle group arranged in the center thereof and second nozzle groups arranged further on outer sides than the first nozzle group. Inter-nozzle pitches of the second nozzle groups are larger than inter-nozzle pitches of the first nozzle group. A direction in which nozzles of the second nozzle group eject an ink and a direction in which nozzles of the first nozzle group eject the ink are different.

Ink-jet head and head unit

An ink-jet recording apparatus is provided which includes an ink-jet head having a plurality of ink chambers and a common ink chamber which communicates with each of the plurality of ink chambers to supply ink to the plurality of ink chambers, the ink-jet head maintaining the plurality of ink chambers at a negative pressure in image recording, selecting one of the plurality of ink chambers on the basis of printing data and causing change in volume of the selected ink chamber, and thereby performing image recording by discharging the ink from a nozzle, and a pressure section which applies a positive pressure to the plurality of ink chambers when the ink-jet head is in a left state, the positive pressure being a pressure at which the ink is not discharged from the nozzle.

Ink-jet recording apparatus and method of preventing clogging of nozzle discharging ink

An ink jet recording apparatus in which a filter unit to filter ink with a filter having a pore size of 2.2 to 5.8 &#x3bc;m is provided in an ink supply channel to supply the ink to an ink jet head. The ink flowing through the ink supply channel is quickly filtered by the filter unit, and supplied to the ink jet head without delay, thus the occurrence of ink discharge failure can be reliably suppressed.

Ink jet recording apparatus and ink jet head

An ink jet recording apparatus having an ink jet head to discharge supplied ink from a nozzle, a deaeration device to deaerate dissolved gas from the ink supplied to the ink jet head, an ink reservoir, provided in an ink channel between the deaeration device and the ink jet head, to apply negative pressure by a difference in level of the ink reservoir surface and the nozzle, and a preventative member, floated on the surface of ink in the ink reservoir, to prevent contact between the ink and air. Even when the ink, from which dissolved gas has been deaerated by the deaeration device, is stored in the ink reservoir in a course of supplying process of the ink, re-dissolution of gas in the ink in the ink reservoir can be suppressed. Further, the ink can be reliably pressurized in the ink jet head, and ink droplets can be excellently discharged from the nozzle.

Ink jet recording apparatus

An ink jet head having ink chambers, energy-generating elements provided in the ink chambers, respectively, and ink outlet ports communicating with the ink chambers, respectively. The ink jet head may be left unused for a time longer than a predetermined time, with a meniscus formed in each ink outlet port. In this case, a drive pulse is applied to each energy-generating element several times, thereby forcing the ink outwards from the ink outlet port and increasing a surface area of the ink from a surface area of the meniscus. Then, a negative pressure is applied in each ink chamber, thereby drawing the ink back toward the ink chamber, thus forming a meniscus again in the ink outlet port. In this condition, a drive pulse is applied to the energy-generating element, thus ejecting an ink droplet from the ink outlet port to record data.

Method and apparatus for driving an ink jet head

In an ink jet recording apparatus having two head units, each having a large number of ink nozzles arranged in a line, assembled so that they overlap with each other, an 8-shade image signal is entered into a correction circuit and a line direction position signal is input into a position signal decision circuit. When the position signal decision circuit decides that the position signal represents the overlapping zone of the head units, the shade level of the image signal is divided between the head units. For example, when the shade level of the image signal is 7, one of the head units is allotted the shade level and the other is allotted the shade level. The overlapping nozzles in a pair eject droplets of ink to form one dot.

An ink jet head is provided having ink chambers, energy-generating elements provided in the ink chambers, respectively, and ink outlet ports communicating with the ink chambers, respectively. The ink jet head may be left unused for a time longer than a predetermined time, with a meniscus formed in each ink outlet port. In this case, a drive pulse is applied to each energy-generating element several times, thereby forcing the ink outwards from the ink outlet ports and increasing a surface area of the ink from a surface area of the meniscus. Then, a negative pressure is applied in each ink chamber, thereby drawing the ink back toward the ink chambers, thus forming a meniscus again in the ink outlet ports. In this condition, a drive pulse is applied to the energy-generating elements, thus ejecting an ink droplet from the ink outlet ports to record data.

An image printing apparatus comprises a storage section and a control section. The storage section stores an absorbing speed information in a storage area, the absorption speed information is a measured speed at which a recording medium used for a printing process absorbs an ink used for the printing process. And the control section controls an ink head so as to perform first dot recording which records a plurality of dots on the recording medium by a pitch of an ink ejection opening of the ink head, and moves the recording medium relatively with the ink head and controls the ink head so as to perform second dot recording which records a plurality of dots between a plurality of dots recorded by first dot recording, in accordance with a print interval time determined based on the absorption speed information stored in the storage section.

Growing community of inventors

Mishima, Japan

Takahisa Ikeda