Abstract: An ink supply device is provided in correspondence with a recording head unit. The recording head unit has a recording head that ejects ink drops onto a recording medium on the basis of image information. Additionally the recording head unit has a sub ink tank provided with an air communication hole. The ink supply device includes an ink supply unit that supplies ink to the sub ink tank by reducing pressure on the inside of the sub ink tank through a pressure reduction part. A sealing part at least implements sealing of the air communication hole while the ink supply unit is reducing the pressure inside the sub ink tank.

Abstract: The present invention provides an ink jet recording apparatus which can prevent problems such as image defects caused by shortage of ink, and decreases in the printing speed from occurring. When execution of a print job is instructed, a printing processing for the print job is started. The number of pixels which have been actually printed is added to a current pixel count C1, and it is determined whether or not the print job is finished. When it is determined that the print job is finished and the pixel count C1 exceeds a predetermined number of pixels X1, an ink supply unit is controlled so that ink of a predetermined proportion A (%) of the amount of ink used, which amount corresponds to the pixel count C1, is supplied to a sub-ink tank.

Abstract: An ink supply device is provided in correspondence with a recording head unit. The recording head unit has a recording head that ejects ink drops onto a recording medium on the basis of image information. Additionally the recording head unit has a sub ink tank provided with an air communication hole. The ink supply device includes an ink supply unit that supplies ink to the sub ink tank by reducing pressure on the inside of the sub ink tank through a pressure reduction part. A sealing part at least implements sealing of the air communication hole while the ink supply unit is reducing the pressure inside the sub ink tank.

Abstract: An ink supply device is provided in correspondence with a recording head unit. The recording head unit has a recording head that ejects ink drops onto a recording medium on the basis of image information. Additionally the recording head unit has a sub ink tank provided with an air communication hole. The ink supply device includes an ink supply unit that supplies ink to the sub ink tank by reducing pressure on the inside of the sub ink tank through a pressure reduction part. A sealing part at least implements sealing of the air communication hole while the ink supply unit is reducing the pressure inside the sub ink tank.

Abstract: The present invention provides an ink jet recording apparatus which can prevent problems such as image defects caused by shortage of ink, and decreases in the printing speed from occurring. When execution of a print job is instructed, a printing processing for the print job is started. The number of pixels which have been actually printed is added to a current pixel count C1, and it is determined whether or not the print job is finished. When it is determined that the print job is finished and the pixel count C1 exceeds a predetermined number of pixels X1, an ink supply unit is controlled so that ink of a predetermined proportion A (%) of the amount of ink used, which amount corresponds to the pixel count C1, is supplied to a sub-ink tank.

Abstract: An ink supply device is provided in correspondence with a recording head unit. The recording head unit has a recording head that ejects ink drops onto a recording medium on the basis of image information. Additionally the recording head unit has a sub ink tank provided with an air communication hole. The ink supply device includes an ink supply unit that supplies ink to the sub ink tank by reducing pressure on the inside of the sub ink tank through a pressure reduction part. A sealing part at least implements sealing of the air communication hole while the ink supply unit is reducing the pressure inside the sub ink tank.

Abstract: A recording apparatus having a print head for printing characters on a medium and an ink tank for holding ink to be supplied to the print head. The ink tank includes an ink chamber having an ink holding member and an ink supplying port. A first meniscus forming member is located in the ink supplying port so as to be in communication with the ink holding member. The print head includes an ink introducing port for receiving ink from the ink tank and a second meniscus forming member located in the ink introducing port. When the ink tank is attached to the print head, the ink introducing port is coupled with the ink supplying port. An ink passing member is located in the portion where the ink introducing port is coupled with the ink supplying port. The ends of the ink passing member are in contact with the first meniscus forming member and the second meniscus forming member. The ink passing member is subject to only minor changes in volume upon contact with ink.

Abstract: An elastic jointing member 22 with an umbrella-like portion with an opening and a flat part is provided in a jointing portion between a recording head 21 and an ink tank 1. When the ink tank 1 is attached to the recording head 21, the umbrella-like portion of the elastic jointing member 22 is pressed against the ink tank and elastically deformed inward. As a result, an ink passage is formed which is airtightly sealed. In the process of pressing the umbrella-like portion against the ink tank, the umbrella-like portion comes in contact with the flat part, to thereby prevent air from staying in the ink passage. Protrusions or grooves may be provided between the umbrella-like portion and the flat part. With the protrusions or the groove, the umbrella-like portion is not glued to the flat part.

Abstract: An ink jet printer which causes ink to fly to a recording medium to form an image, comprising: plural nozzles functioning as ink ejection ports; plural individual flow paths which are disposed with respectively corresponding to the nozzles, the individual flow paths respectively having driving elements which eject internal ink through the nozzles; a common liquid chamber which communicates with the individual flow paths, the common liquid chamber having an opening portion through which ink is supplied into the chamber; an ink supply path which has a sectional area smaller than a sectional area of the opening portion of the common liquid chamber, the ink supply path being connected to the opening portion to guide ink to the common liquid chamber; and an ink supply source for supplying ink through the ink supply path.

Abstract: An ink supply passage 16 has a large cross-sectional area and ink tanks 6 are connected to the top of the ink supply passage 16. An ink supply passage 17 is a flow passage shaped like a semicylinder and has a cross-sectional area equal to or smaller than the cross-sectional area of the ink supply passage 16. Even if bubbles are mixed into the ink supply passage 17, they adhere to the upper portion of the flow passage 17 and do not flow into lower corners, so that a flow passage can be provided and the ink flow is not hindered. Since an ink supply passage 19 connected to a head chip 4 has a small diameter, bubbles mixed into the ink supply passage 19 can be removed by maintenance for sucking ink forcibly. Bubbles mixed upstream are not transported to the ink supply passage 19 because of the flow rate difference caused by the cross-sectional area difference.

Abstract: A method of recovering ink jet performance of an ink jet recording apparatus, comprises the steps of: first covering a nozzle surface of an ink jet head with a cap; sucking the nozzle surface of the ink jet head to a vacuum by driving a variable vacuum suction pump for suction at a normal suction speed, the variable vacuum suction pump being connected to the cap through a communication member so as to communicate therewith; and thereafter driving the variable vacuum suction pump for idle suction at a speed that is lower than the normal suction speed with the cap moved away from the nozzle surface of the ink jet head.