Abstract: An ink supplier includes a supply reservoir that stores ink to be supplied to a plurality of heads in an ink-jet printing apparatus. The supply reservoir includes: a first horizontal reservoir of a cylindrical shape having a plurality of supply ports communicating with a plurality of heads; and a first vertical reservoir having a side surface provided with a first opening directly or indirectly communicating with one end of the first horizontal reservoir. A top surface of the first horizontal reservoir is tilted from a horizontal direction at an angle of tilt equal to or greater than 0.3° in such a manner as to extend upward from the other end toward the first opening or the one end. Thus, air bubbles in the first horizontal reservoir move along the top surface into the first vertical reservoir through the first opening and can be removed from the first horizontal reservoir.

Abstract: An ink supplier includes: a supply reservoir storing ink to be supplied to a plurality of heads; and a discharge pipe used for discharging the ink from the supply reservoir. The supply reservoir includes: a cylindrical first horizontal reservoir having a plurality of supply ports each communicating with one of the plurality of heads; and a first vertical reservoir having a side surface provided with a first opening communicating with one end of the first horizontal reservoir. The first horizontal reservoir has a bottom surface that is tilted from a horizontal direction at an angle of tilt equal to or greater than 0.3º in such a manner as to extend downward from the one end toward the other end. The first horizontal reservoir includes a first discharge port provided at a bottom portion of the first horizontal reservoir at the other end and communicably connected to the discharge pipe.

Abstract: An ink is circulated in a circulation path including a supply sub-tank, a discharge head and a collection sub-tank in a head unit. If the amount of the ink in the head unit decreases, the ink stored in the buffer tank is replenished to the head unit. On the other hand, in a first non-replenishment time during which the ink is not replenished, the ink is circulated through the buffer tank, the collection sub-tank and the supply sub-tank in this order. Thus, a temperature fluctuation of the replenishment ink stored in the buffer tank is suppressed. As a result, even if the ink is replenished to the head unit from the buffer tank, physical properties, particularly a viscosity, of the ink do not largely vary.

Abstract: The present invention is a position adjustment method for head units arrayed in a predetermined width direction attachably to and detachably from a base member. A position of a second head unit in the width direction and a rotation direction are respectively adjusted while the second head unit is engaging a tip part of a reference pin. More particularly, a width direction adjuster moves the second head unit in the width direction with a first head unit kept fixed to the base member. In this way, the gap between the first head unit and the second head unit is adjusted. Further, a rotation direction adjuster moves the second head unit in the orthogonal direction at a separation position distant from the reference pin. In this way, a rotation direction position of the second head unit with respect to the tip part of the reference pin is adjusted.

Abstract: An ink is circulated in a circulation path including a supply sub-tank, a discharge head and a collection sub-tank in a head unit. If the amount of the ink in the head unit decreases, the ink stored in the buffer tank is replenished to the head unit. On the other hand, in a first non-replenishment time during which the ink is not replenished, the ink is circulated through the buffer tank, the collection sub-tank and the supply sub-tank in this order. Thus, a temperature fluctuation of the replenishment ink stored in the buffer tank is suppressed. As a result, even if the ink is replenished to the head unit from the buffer tank, physical properties, particularly a viscosity, of the ink do not largely vary.

Abstract: In the invention, pipes and the like are guided in parallel to a second horizontal direction according to collective movements of printing bar units while being stored and protected by a protecting/guiding member arranged outside and adjacent to a body frame. In this way, breakage of the pipes and the like during the collective movements of printing bar units is reliably prevented. Moreover, the pipes and the like stored in the protecting/guiding member move outside the body frame and are not present inside the body frame. As a result, a work space can be secured without being limited by the collective movements of the printing bar units to the maintenance space.

Abstract: The present invention includes a head holder configured to collectively holding a plurality of discharge heads and a collective head mover configured to move the head holder between a printing space above the printing medium being conveyed in the conveying direction and a retraction space separated from the printing space. Therefore, is provided a printing technique capable of printing a high-quality image at low cost by discharging inks from a plurality of discharge heads arranged adjacent to each other in a direction parallel to a conveying direction of a printing medium while reciprocally moving the respective discharge heads between a printing space and a retraction space.

Abstract: Closing the replenishing solenoid valve V11 and opening the return solenoid valve V12 prohibits passage of the ink fed using the replenishing pump 951 through the replenishing solenoid valve V11 and allows this ink to pass through the return solenoid valve V12. In this way, the ink is circulated along the circulation path Cc2 (second circulation path) along which the ink is fed from the buffer tank 95a to the branch point J though the replenishing pipe 95b and then fed from the branch point J to the buffer tank 95a through the return pipe 961.

Abstract: Both end parts of a cord are fixed to a maintenance mounting frame, and an intermediate part of the cord is laid on a first body-side rotating member, a head-side rotating member and a second body-side rotating member. Here, when a motor is driven, the movement restriction of the cord is released and a movement of a head mounting frame is restricted, whereby only the maintenance mounting frame moves together with a maintenance part while the movement of the head mounting frame is restricted. Further, when the motor is driven, a movement of the cord is restricted and the movement restriction of the head mounting frame is released, whereby only the head mounting frame moves together with a discharge head while a movement of the maintenance part is restricted.

Abstract: A head unit to be detachably arrayed in a predetermined array direction on a base member includes: an ink discharge head having a nozzle surface configured to discharge an ink; a head holder attachable to and detachable from the base member while holding the ink discharge head in a holding region; and a posture adjustment mechanism configured to adjust a posture of the nozzle surface with respect to the head holder by rotating the ink discharge head with respect to the head holder about an axis of rotation perpendicular to both a surface normal to the nozzle surface and the array direction in a state where the head holder is not attached to the base member.

Abstract: In the invention, pipes and the like are guided in parallel to a second horizontal direction according to collective movements of printing bar units while being stored and protected by a protecting/guiding member arranged outside and adjacent to a body frame. In this way, breakage of the pipes and the like during the collective movements of printing bar units is reliably prevented. Moreover, the pipes and the like stored in the protecting/guiding member move outside the body frame and are not present inside the body frame. As a result, a work space can be secured without being limited by the collective movements of the printing bar units to the maintenance space.

Abstract: The printing medium M after color printing is performed on the front surface M1 (recording surface) by the color printing unit 32 can be conveyed while the front surface M1 and the back surface M2 of the printing medium M are inverted twice by the only rollers 471 to 478 (rotary bodies) in contact with the back surface M2 (non-recording surface) of the printing medium M (inverting conveying part 47). In this way, without providing air turn bars, a time to convey the printing medium M from the color printing unit 32 to the white printing unit 33 can be secured while the printing medium M is firmly supported by the rollers 471 to 478 in contact with the back surface M2 of the printing medium M.

Abstract: An ink is circulated in a circulation path including a supply sub-tank, a discharge head and a collection sub-tank in a head unit. If the amount of the ink in the head unit decreases, the ink stored in the buffer tank is replenished to the head unit. On the other hand, in a first non-replenishment time during which the ink is not replenished, the ink is circulated through the buffer tank, the collection sub-tank and the supply sub-tank in this order. Thus, a temperature fluctuation of the replenishment ink stored in the buffer tank is suppressed. As a result, even if the ink is replenished to the head unit from the buffer tank, physical properties, particularly a viscosity, of the ink do not largely vary.

Abstract: Both end parts of a cord are fixed to a maintenance mounting frame, and an intermediate part of the cord is laid on a first body-side rotating member, a head-side rotating member and a second body-side rotating member. Here, when a motor is driven, the movement restriction of the cord is released and a movement of a head mounting frame is restricted, whereby only the maintenance mounting frame moves together with a maintenance part while the movement of the head mounting frame is restricted. Further, when the motor is driven, a movement of the cord is restricted and the movement restriction of the head mounting frame is released, whereby only the head mounting frame moves together with a discharge head while a movement of the maintenance part is restricted.

Abstract: The printing medium M after color printing is performed on the front surface M1 (recording surface) by the color printing unit 32 can be conveyed while the front surface M1 and the back surface M2 of the printing medium M are inverted twice by the only rollers 471 to 478 (rotary bodies) in contact with the back surface M2 (non-recording surface) of the printing medium M (inverting conveying part 47). In this way, without providing air turn bars, a time to convey the printing medium M from the color printing unit 32 to the white printing unit 33 can be secured while the printing medium M is firmly supported by the rollers 471 to 478 in contact with the back surface M2 of the printing medium M.

Abstract: An ink feeding mechanism includes an ink reservoir 31, a subtank 32 for temporarily storing ink, a decompression channel 44 for decompressing the subtank 32 to a fixed pressure, an ink force-feed channel 41 interconnecting the ink reservoir 31 and subtank 32, a first switch valve 35 mounted on the ink force-feed channel 41, a communication channel 43 interconnecting the subtank 32 and an inkjet head 10, an ink circulating channel 42 interconnecting the communication channel 43 and ink reservoir 31, and a second switch valve 34 mounted on the ink circulating channel 42. A lid member 51 forming part of a chamber has a pressure regulating channel 45 connected thereto, which is connected also to a force-feed channel 46 with a pressure pump 37 mounted thereon, and an exhaust channel 47 with an exhaust pump 38 mounted thereon.

Abstract: At least two switching devices each including a substrate formed of a wide bandgap semiconductor, source and gate electrodes formed in a principal surface side of the substrate, and a drain electrode formed on the back surface of the substrate are stacked so that respective upper surface sides of the switching face each other.

Abstract: With the use of three inverter circuits controlled by a single processor, the controller of the motor-driving apparatus provides a rotation drum-driving motor, a compressor-driving motor and a blow fan-driving motor with a simultaneous sinusoidal-wave control. The configuration above offers stable sinusoidal-wave drive, reducing vibration noise of the rotation drum, the compressor and the blow fan.

Abstract: An ink feeding mechanism includes an ink reservoir 31, a subtank 32 for temporarily storing ink, a decompression channel 44 for decompressing the subtank 32 to a fixed pressure, an ink force-feed channel 41 interconnecting the ink reservoir 31 and subtank 32, a first switch valve 35 mounted on the ink force-feed channel 41, a communication channel 43 interconnecting the subtank 32 and an inkjet head 10, an ink circulating channel 42 interconnecting the communication channel 43 and ink reservoir 31, and a second switch valve 34 mounted on the ink circulating channel 42. A lid member 51 forming part of a chamber has a pressure regulating channel 45 connected thereto, which is connected also to a force-feed channel 46 with a pressure pump 37 mounted thereon, and an exhaust channel 47 with an exhaust pump 38 mounted thereon.

Abstract: With the use of three inverter circuits controlled by a single processor, the controller of the motor-driving apparatus provides a rotation drum-driving motor, a compressor-driving motor and a blow fan-driving motor with a simultaneous sinusoidal-wave control. The configuration above offers stable sinusoidal-wave drive, reducing vibration noise of the rotation drum, the compressor and the blow fan.