Abstract: An ink jet recording head includes a flow passage for a liquid for cooling a recording element substrate. The flow passage is provided inside a support plate that supports the recording element substrate along a recording element array of the recording element substrate. The shortest distance between a recording element and the flow passage at the end of the support plate is larger than the shortest distance between a recording element and the flow passage in the middle of the support plate.

Abstract: The image forming apparatus includes a plurality of photosensitive members, a plurality of exposure portions to perform exposure on the plurality of photosensitive members, a development portion to form a toner image at the plurality of photosensitive members, a transfer medium to which the respective toner images formed on the plurality of photosensitive members are sequentially transferred so as to form an image, and a position correction portion to perform position correction by moving at least one photosensitive member among the plurality of photosensitive members, and the position correction of the photosensitive member is performed by swinging the photosensitive member by the position correction portion having a line on a circumference surface of the photosensitive member corresponding to an exposure position of the exposure portion as the center axis.

Abstract: The image forming apparatus includes a plurality of photosensitive members, a plurality of exposure portions to perform exposure on the plurality of photosensitive members, a development portion to form a toner image at the plurality of photosensitive members, a transfer medium to which the respective toner images formed on the plurality of photosensitive members are sequentially transferred so as to form an image, and a position correction portion to perform position correction by moving at least one photosensitive member among the plurality of photosensitive members, and the position correction of the photosensitive member is performed by swinging the photosensitive member by the position correction portion having a line on a circumference surface of the photosensitive member corresponding to an exposure position of the exposure portion as the center axis.

Abstract: There is provided an inkjet printing apparatus having a printhead equipped with printing element row that includes printing elements having a plurality of heat-producing resistance elements. The apparatus includes a temperature sensing unit which senses the temperature of the printhead, a temperature distribution storage unit in which a temperature distribution along the printing element row, a temperature gradient calculating unit which calculates the temperature gradient of the printing element row from the temperature of the printhead sensed by the temperature sensing units, a predicting unit which predicts the temperature of each printing element using the temperature gradient and the temperature distribution along the printing element row, and a control unit which applies discharge pulses, which are decided based upon the predicted temperature from the predicting unit, to each of the printing elements.

Abstract: A method is provided for inspecting a recording head including a plurality of electrothermal conversion elements and a temperature detection element placed above or below each of the plurality of electrothermal conversion elements. The method includes driving the electrothermal conversion element, determining whether there is a change in slope of a temperature fall process in temperature detected by the temperature detection element during a predetermined time, if it is determined that there is a change in slope of the temperature fall process, obtaining a timing of the change in slope, and determining whether ink is discharged normally based on the obtained timing of the change in slope and a predetermined timing of a change in slope of the temperature fall process.

Abstract: An ink jet recording head includes a flow passage for a liquid for cooling a recording element substrate. The flow passage is provided inside a support plate that supports the recording element substrate along a recording element array of the recording element substrate. The shortest distance between a recording element and the flow passage at the end of the support plate is larger than the shortest distance between a recording element and the flow passage in the middle of the support plate.

Abstract: A temperature rise of a head due to a printing operation with a higher speed and a higher density is suppressed. To realize this, an inkjet printing head is provided in which a plurality of printing element substrates having an ejection opening array consisting of a plurality of ejection openings for ejecting ink are arranged on a support plate in a direction of the ejection opening array. The support plate includes therein a heat pipe and a flow path through which cooling liquid is flowed.

Abstract: An image forming apparatus includes first and second image bearing members on which a toner images are to be formed; a conveying member onto which the toner images are to be transferred; a conveying member position index detecting device for detecting a conveying member position index provided on the conveying member along the movement direction of the conveying member; an image bearing member position index detecting device for detecting the image bearing member position indices provided on the second image bearing member along a rotational direction of the second image bearing member; an adjusting device for adjusting a rotational speed of the second image bearing member; a controller for controlling the adjusting device so as to adjust a position of an image bearing member position index correspondingly to the conveying member position index, on the basis of detection results of the conveying member position index detecting device and the image bearing member position index detecting device; and an initial

Abstract: In order to prevent, in an operation for circulating liquid, an ejection port from sucking air or the ejection port from pushing out liquid, the subtank for temporally storing ink to be supplied to the ink jet head includes the air communication passage opened or closed by the air communication valve. The ink jet head is communicated with the subtank by the first passage and the second passage to constitute one circulation passage. In order to circulate the ink in the subtank into the common liquid chamber, the main pump is energized while the air communication valve is being closed. When the circulation operation is stopped, the air communication valve is opened immediately after the stoppage of the main pump, thereby eliminating the differential pressure between the common liquid chamber and the subtank within a short period of time.

Abstract: In order to prevent, in an operation for circulating liquid, an ejection port from sucking air or the ejection port from pushing out liquid, the subtank for temporally storing ink to be supplied to the ink jet head includes the air communication passage opened or closed by the air communication valve. The ink jet head is communicated with the subtank by the first passage and the second passage to constitute one circulation passage. In order to circulate the ink in the subtank into the common liquid chamber, the main pump is energized while the air communication valve is being closed. When the circulation operation is stopped, the air communication valve is opened immediately after the stoppage of the main pump, thereby eliminating the differential pressure between the common liquid chamber and the subtank within a short period of time.

Abstract: There is provided an inkjet printing apparatus having a printhead equipped with printing element row that includes printing elements having a plurality of heat-producing resistance elements. The apparatus includes a temperature sensing unit which senses the temperature of the printhead, a temperature distribution storage unit in which a temperature distribution along the printing element row, a temperature gradient calculating unit which calculates the temperature gradient of the printing element row from the temperature of the printhead sensed by the temperature sensing units, a predicting unit which predicts the temperature of each printing element using the temperature gradient and the temperature distribution along the printing element row, and a control unit which applies discharge pulses, which are decided based upon the predicted temperature from the predicting unit, to each of the printing elements.

Abstract: A method is provided for inspecting a recording head including a plurality of electrothermal conversion elements and a temperature detection element placed above or below each of the plurality of electrothermal conversion elements. The method includes driving the electrothermal conversion element, determining whether there is a change in slope of a temperature fall process in temperature detected by the temperature detection element during a predetermined time, if it is determined that there is a change in slope of the temperature fall process, obtaining a timing of the change in slope, and determining whether ink is discharged normally based on the obtained timing of the change in slope and a predetermined timing of a change in slope of the temperature fall process.

Abstract: In an ink jet recording apparatus using a recording head that discharges ink by applying thermal energy produced in response to driving a heater to ink, a change in temperature occurring when the heater is driven is measured by a temperature sensor disposed directly below the heater. A discharge state for each nozzle can be determined by determination as to whether an inflection point is present in a curve representing the change in temperature occurring after the driving for discharging ink.

Abstract: In order to prevent, in an operation for circulating liquid, an ejection port from sucking air or the ejection port from pushing out liquid, the subtank for temporally storing ink to be supplied to the ink jet head includes the air communication passage opened or closed by the air communication valve. The ink jet head is communicated with the subtank by the first passage and the second passage to constitute one circulation passage. In order to circulate the ink in the subtank into the common liquid chamber, the main pump is energized while the air communication valve is being closed. When the circulation operation is stopped, the air communication valve is opened immediately after the stoppage of the main pump, thereby eliminating the differential pressure between the common liquid chamber and the subtank within a short period of time.

Abstract: A liquid ejection apparatus comprises a liquid bag for containing liquid to be supplied to a liquid ejection head and is adapted to generate negative pressure in the liquid ejection head by a water head difference between the liquid ejection head and the liquid bag. The liquid bag is arranged so that, of two sides of the liquid bag having the largest areas, the side facing in a direction opposite to the direction of gravity is rigidly held at least partly and the other side is freely movable. The liquid bag is provided with a means for detecting an amount of liquid remaining in the liquid bag by reference to a position of the side facing in the direction of gravity, and the detecting means is adapted to move according to the amount of liquid contained in the liquid bag.

Abstract: A liquid ejection apparatus comprises a liquid bag for containing liquid to be supplied to a liquid ejection head and adapted to generate negative pressure in the liquid ejection head by a difference of water head between the liquid ejection head and the liquid bag. The liquid bag is so arranged as to make a side of the liquid bag facing a direction opposite to the direction of gravity out of two sides having a largest area to be rigidly held at least partly and the other side to be freely movable. The liquid bag is provided with a means for detecting an amount of liquid remaining in the liquid bag by a position of the other side facing the direction of gravity and adapted to move according to the amount of liquid contained in the liquid bag.

Abstract: An ink tank includes an ink containing portion for containing ink, a bottom surface provided with three projections for supporting the ink tank, an ink supply portion for leading ink out of the ink containing portion to the exterior a top surface opposing to said bottom surface, and a plurality of lateral surfaces adjacent to the bottom and top surfaces. The plurality of lateral surfaces include one set of opposing surfaces extended in a lengthwise direction of the ink tank. A grip portion is provided at one end of the ink tank in the lengthwise direction of insertion thereof. Two of the three projections are provided on the bottom surface in an opposed relation in areas near the opposing surfaces of the plurality of lateral surfaces, the ink supply portion being provided in an area of the top surface opposed to an area located on or within lines connecting the three projections.

Abstract: Disclosed is an ink tank coupling method for an ink jet recording apparatus comprising a recording head, an ink supply needle, and a moving unit for moving the ink supply needle to a predetermined position, the recording apparatus being able to detachably mount an ink tank containing ink supplied to the recording head. The method comprises a step of holding and fixing the ink tank to a predetermined position by releasing a movement preventing unit which prevents movement of the ink supply needle caused by the moving unit, and pressing the ink tank to abut a reference surface with an operation of attaching the ink tank to the recording apparatus, and a step of inserting the ink supply needle to the predetermined position in the ink tank by the moving unit after the holding and fixing step.

Abstract: Disclosed is an ink tank coupling method for an ink jet recording apparatus including a recording head, an ink supply needle, and a moving unit for moving the ink supply needle to a predetermined position, the recording apparatus being able to detachably mount an ink tank containing ink supplied to the recording head. The method includes a step of holding and fixing the ink tank to a predetermined position by releasing a movement preventing unit which prevents movement of the ink supply needle caused by the moving unit, and pressing the ink tank to abut a reference surface with an operation of attaching the ink tank to the recording apparatus, and a step of inserting the ink supply needle to the predetermined position in the ink tank by the moving unit after the holding and fixing step.

Abstract: A liquid ejection printing apparatus performing printing by ejecting a liquid toward a printing medium includes a liquid ejection head portion having a liquid ejecting printing head ejecting a liquid and a first tank holding the liquid to be supplied to the head, a second tank holding a liquid to be supplied to the first tank and having an atmosphere communicating opening for introducing an atmospheric air, a third tank receiving the liquid from the first tank and capable of supplying the liquid to the second tank, a first liquid supply passage for communicating the first tank and the second tank, a second liquid supply passage for communicating the second tank and the third tank, a third liquid supply passage for communicating the third tank to the first tank, the first tank and the third tank each forming an enclosed space excluding supply passages connected respectively thereto, a pump capable of sucking a gas within the third tank provided in a passage other than the first, second and third supply passage