JP2020055321A - Liquid discharge head, liquid discharge unit, and device for discharging liquid - Google Patents

Abstract

To solve the problem of a complicated structure caused by a necessity of providing a circulation port for each circulation flow path when the circulation flow path is arranged for each of two nozzle rows.SOLUTION: A liquid discharge head has: two nozzle rows 4A and 4B having a plurality of nozzles 4 for discharging liquid arrayed; a plurality of individual liquid chambers 6 communicating with respective nozzles 4 of the nozzle rows 4A and 4B; and two circulation flow paths 41A and 41B corresponding to the nozzle rows 4A and 4B, and communicating with the plurality of individual liquid chambers 6. The two circulation flow paths 41A and 41B communicate with each other through bridging flow paths 44 arranged in a direction crossing a nozzle arraying direction. The bridging flow paths 44 and the circulation flow paths 41A and 41B are arranged at different positions in a thickness direction of flow path plates 2 that form the bridging flow paths 44 and the circulation flow paths 41A and 41B. The circulation flow paths 41 are formed on a second flow path plate 52, and the bridging flow paths 44 are formed on a third flow path plate. The second flow path plate 52 is overlapped with a third flow path plate 53, thereby the circulation flow paths 41 are connected with the bridging flow paths 44.SELECTED DRAWING: Figure 7

Description

  The present invention relates to a liquid discharge head, a liquid discharge unit, and a device for discharging liquid.

  As a liquid discharge head (droplet discharge head) that discharges liquid, a circulation type head that circulates liquid in a plurality of individual liquid chambers is known.

  For example, independent circulation channels are arranged in the nozzle arrangement direction corresponding to two rows of pressure generation chambers (nozzle rows), and each circulation channel is communicated with a passage that passes through each pressure generation chamber and the nozzle. There is a known type in which liquids of different colors are ejected from each nozzle row (Patent Document 1).

JP 2012-143948 A

  By the way, if one circulation channel is arranged between the individual liquid chambers (pressure generating chambers) in order to discharge the same type of liquid from the two nozzle rows, the width direction of the head (perpendicular to the nozzle arrangement direction) Direction) The size increases.

  Therefore, as disclosed in Patent Literature 1, when, for example, two circulation channels are arranged for each nozzle row, it becomes necessary to provide a circulation port for each circulation channel, and the configuration becomes complicated. Occurs.

  The present invention has been made in view of the above problems, and has as its object to share a plurality of circulation channels with a simple configuration while securing the rigidity of a channel member.

In order to solve the above-mentioned problems, a liquid discharge head according to claim 1 of the present invention is provided.
At least two nozzle rows in which a plurality of nozzles for discharging liquid are arranged;
A plurality of individual liquid chambers communicating with each nozzle of the nozzle row,
A common liquid chamber that supplies the liquid to the plurality of individual liquid chambers,
Having at least two circulation channels communicating with each of the plurality of individual liquid chambers and collecting the liquid,
The circulation flow path is disposed on the same side as the common liquid chamber with respect to the nozzle in a direction orthogonal to the nozzle arrangement direction and the liquid discharge direction,
The two circulation channels communicate with each other via a bridge channel arranged in a direction crossing the nozzle arrangement direction,
The cross-linking channel and the circulation channel are arranged at different positions in the thickness direction of a member forming the cross-linking channel and the circulation channel,
The circulation channel is formed in a first channel member,
The bridge channel is formed in a second channel member,
The first flow path member and the second flow path member are overlapped to connect the circulation flow path and the cross-linking flow path.

  ADVANTAGE OF THE INVENTION According to this invention, while ensuring the rigidity of a flow path member, it is possible to share a plurality of circulation flow paths with a simple configuration.

FIG. 2 is an explanatory perspective view of an external appearance of an example of a liquid ejection head according to the present invention. FIG. 3 is an explanatory cross-sectional view in a direction (longitudinal direction of a liquid chamber) orthogonal to a nozzle arrangement direction of the head. FIG. 3 is an explanatory cross-sectional view in a direction (longitudinal direction of a liquid chamber) orthogonal to a nozzle arrangement direction of the head. FIG. 6 is an explanatory cross-sectional view corresponding to the line CC of FIG. 5 for describing the first embodiment of the present invention. FIG. 5 is a sectional explanatory view corresponding to the line AA in FIG. 4. FIG. 5 is a sectional explanatory view corresponding to the line BB of FIG. 4. It is a typical perspective explanatory view of the part which concerns on a circulation flow path similarly. It is principal part sectional explanatory drawing provided for description of 2nd Embodiment of this invention. It is a plane explanatory view of a nozzle plate similarly. It is a plane explanatory view of a 1st channel board similarly. It is a plane explanatory view of a 2nd channel plate similarly. It is a plane explanatory view similarly to a 3rd flow path plate. It is a plane explanatory view of a 4th channel plate similarly. It is a plane explanatory view of a 5th channel plate similarly. It is a plane explanatory view of a sixth channel plate similarly. It is a plane explanatory view of a diaphragm member similarly. It is a plane explanatory view of a frame member similarly. It is a plane explanatory view of a diaphragm member used for explanation of a 3rd embodiment of the present invention. It is a plane explanatory view of a frame member similarly. FIG. 14 is an explanatory sectional view for explaining a fourth embodiment of the present invention. FIG. 21 is a sectional view taken along the line DD of FIG. 20. FIG. 3 is an explanatory plan view of the channel plate on the nozzle plate side. FIG. 3 is an explanatory plan view of the flow path plate on the side of the diaphragm member. FIG. 2 is a side view illustrating a mechanism of an example of a device that discharges a liquid according to the present invention including the liquid discharge unit according to the present invention. It is principal part planar explanatory drawing of the same mechanical part.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. An example of the liquid ejection head according to the present invention will be described with reference to FIGS. 1 is an explanatory perspective view of the appearance of the liquid discharge head, FIG. 2 is a cross-sectional explanatory view in a direction (longitudinal direction of the liquid chamber) orthogonal to the nozzle arrangement direction of the head, and FIG. 3 is a direction orthogonal to the nozzle arrangement direction of the head. FIG. 3 is an explanatory cross-sectional view (in a longitudinal direction of a liquid chamber). In FIG. 1, the ejection direction is downward, but in FIG. 2 and subsequent figures, the ejection direction is upward.

  In this liquid discharge head, a nozzle plate 1, a flow path plate 2, and a diaphragm member 3 as a wall member are laminated and joined. Further, a piezoelectric actuator 11 for displacing the diaphragm member 3, a frame member 20 as a common liquid chamber member, and a cover 21 are provided.

  The nozzle plate 1 has a plurality of nozzles 4 for discharging liquid.

  The flow path plate 2 has a passage 5 that communicates with the nozzle 4, an individual liquid chamber 6 that communicates with the passage 5, a fluid resistance portion 7 that communicates with the individual liquid chamber 6, and a liquid introduction portion (passage) 8 that communicates with the fluid resistance portion 7. Holes and grooves are formed.

  The diaphragm member 3 has an opening 9 through which the liquid introduction part 8 and a common liquid chamber 10 formed in the frame member 20 pass.

  The diaphragm member 3 is a wall member that forms a wall surface of the individual liquid chamber 6 of the flow path plate 2. The vibration plate member 3 has a two-layer structure, and is formed from a first layer forming a thin portion and a second layer forming a thick portion from the flow path plate 2 side, and the first layer corresponds to the individual liquid chamber 6. A deformable vibration region 30 is formed at the portion where the vibration occurs.

  A piezoelectric actuator 11 including an electromechanical transducer as driving means (actuator means, pressure generating means) for deforming the vibration area 30 of the diaphragm member 3 is provided on the side of the diaphragm member 3 opposite to the individual liquid chamber 6. Has been arranged.

  The piezoelectric actuator 11 has a piezoelectric member 12 bonded on a base member 13. The piezoelectric member 12 is grooved by half-cut dicing, and a required number of columnar piezoelectric elements (pressure The utility poles 12A and 12B are formed in a comb shape at predetermined intervals.

  Here, the piezoelectric element 12A of the piezoelectric member 12 is a piezoelectric element that is driven by applying a drive waveform, and the piezoelectric element 12B is used as a simple support without providing a drive waveform. However, all the piezoelectric elements 12A and 12B are driven. It can also be used as a piezo element.

  Then, the piezoelectric element 12A is joined to the convex portion 30a which is an island-shaped thick portion formed in the vibration region 30 of the diaphragm member 3. Further, the piezoelectric element 12B is joined to the convex portion 30b which is a thick portion of the diaphragm member 3.

  The piezoelectric member 12 has a structure in which piezoelectric layers and internal electrodes are alternately stacked, and the internal electrodes are respectively drawn out to the end faces to provide external electrodes.

  The frame member 20 has a common liquid chamber 10 to which a liquid is supplied from a head tank or a liquid cartridge.

  In the flow path plate 2, a circulation flow path 41 communicating with each individual liquid chamber 6 on the nozzle plate 1 side opposite to the individual liquid chamber 6, and a circulation resistance portion 42 passing through the circulation flow path 41 and the passage 5 are provided. A groove to be formed is formed.

  The frame member 20 is provided with a supply port 23 communicating with the common liquid chamber 10 and a circulation port (discharge port) 43 communicating with the circulation flow path 41.

  In the liquid ejection head configured as described above, for example, when the voltage applied to the piezoelectric element 12A is reduced from the reference potential, the piezoelectric element 12A is contracted, and the vibration area 30 of the diaphragm member 3 is lowered to reduce the volume of the individual liquid chamber 6. Expands, the liquid flows into the individual liquid chamber 6.

  Thereafter, the voltage applied to the piezoelectric element 12A is increased to extend the piezoelectric element 12A in the stacking direction, and to deform the vibrating region 30 of the diaphragm member 3 in the direction toward the nozzle 4 to contract the volume of the individual liquid chamber 6. Accordingly, the liquid in the individual liquid chamber 6 is pressurized, and the liquid is discharged from the nozzle 4.

  Then, by returning the voltage applied to the piezoelectric element 12A to the reference potential, the vibration region 30 of the vibration plate member 3 is restored to the initial position, and the individual liquid chamber 6 expands to generate a negative pressure. The liquid is filled from the chamber 10 into the individual liquid chamber 6. Then, after the vibration of the meniscus surface of the nozzle 4 is attenuated and stabilized, the operation shifts to the operation for the next ejection.

  Note that the method of driving the head is not limited to the above example (pull-push), but pull-pull, push-push, and the like can be performed according to the drive waveform.

  Next, a first embodiment of the present invention will be described with reference to FIGS. 4 is a cross-sectional explanatory view corresponding to the line CC of FIG. 5, which is used for describing the embodiment, FIG. 5 is a cross-sectional explanatory view corresponding to the line AA of FIG. 4, and FIG. FIG. 7 is a cross-sectional explanatory view corresponding to line B, and FIG. 7 is a schematic perspective explanatory view of a portion related to the circulation flow channel.

  In the present embodiment, the nozzle plate 1 has two nozzle rows 4A and 4B in which a plurality of nozzles 4 are arranged, and has a total of four nozzle rows (see FIG. 9 of a second embodiment described later). Same as).

  In the flow path plate 2, on the side of the nozzle plate 1 opposite to the individual liquid chamber 6, along the nozzle arrangement direction, via the circulation resistance portion 42, corresponding to the two nozzle rows 4 A and 4 B. Two circulation passages 41A and 41B (which are referred to as “circulation passage 41” as described above when not distinguished) are arranged to communicate with the passage 5 and the individual liquid chamber 6. Although two sets of the circulation channels 41A and 41B are arranged, the description will be made with two circulation channels 41A and 41B to simplify the description.

  The two circulation channels 41A and 41B are mutually connected via bridge channels 44, 44 formed at both ends of the channel plate 2 in the nozzle array direction and arranged in a direction intersecting the nozzle array direction. I understand.

  Here, as shown in FIGS. 6 and 7, in the thickness direction of the flow path plate 2 which is a member forming the cross-linking flow path 44 and the circulation flow path 41, the position where the cross-linking flow path 44 and the circulation flow path 41 are different from each other. And are connected at the ends of the respective flow paths 44 and 41.

  Specifically, as shown in FIG. 7, a longitudinal center axis 40 a passing through the center of a cross section (flow path cross section) in a direction orthogonal to the longitudinal direction (here, the nozzle arrangement direction) of the circulation flow path 41, The relationship is such that a longitudinal center axis 40b passing through the center of a cross section (flow path cross section) in a direction orthogonal to the longitudinal direction of the flow path 44 (direction intersecting with the circulation flow path 41) crosses three-dimensionally.

  And, at both ends in the nozzle arrangement direction, circulating ports 43 communicating with the circulating channel 41 via the bridging channels 44 are arranged. At this time, since the two circulation channels 41A and 41B communicate with the bridge channel 44, the circulation port 43 is shared by the two circulation channels 41A and 41B in the direction orthogonal to the nozzle arrangement direction.

  In FIG. 1, since there are two sets of two nozzle rows, two circulation ports 43 are arranged at one end in the nozzle arrangement direction in a direction orthogonal to the nozzle arrangement direction.

  The circulation port 43 communicates with the bridge channel 44 through an opening 46 formed in the diaphragm member 3.

  With this configuration, the liquid supplied from the common liquid chamber 10 to the individual liquid chamber 6 flows into the circulation channel 41 through the circulation resistance part 42, and from the circulation channel 41 to the frame member through the opening 46 of the diaphragm member 3. 20 is discharged from the circulation port 43.

  Here, by connecting (connecting) the two circulation channels 41A and 41B with the bridge channel 44, the two circulation channels 41A and 41B can be shared by a simple configuration, and the two circulation ports 43 are connected to the two circulation channels. 41A and 41B can be shared and the configuration is simplified.

  By arranging the bridge channel 44 and the circulation channel 41 at different positions in the thickness direction of the channel plate 2, it is possible to suppress a decrease in rigidity of the channel plate 2 due to the provision of the bridge channel 44. The rigidity of the head can be ensured.

  That is, in order to suppress the pressure loss difference between the individual liquid chambers 6 generated when the liquid is circulated in the circulation flow channel 41, it is preferable to increase the cross-sectional area of the circulation flow channel 41. At this time, if the cross-linking channel 44 connecting the two circulation channels 41 is arranged at the same position as the circulation channel 41 in the thickness direction of the channel plate 2, the rigidity of the channel plate 2 will be reduced.

  Here, the flow path cross-sectional area of the bridge flow path 44 connecting the two circulation flow paths 41A and 41B does not contribute to the pressure loss difference between the individual liquid chambers 6.

  Therefore, the two circulation channels 41 and the bridge channel 44 are arranged at different positions in the thickness direction of the channel plate 2. That is, in the present embodiment, the central axis 40b of the cross-linking channel 44 is arranged so as to intersect the central axis 40a of the circulation channel 41 in three dimensions.

  This makes it possible to secure the rigidity of the flow path components (flow path plate, flow path member) while increasing the cross-sectional area of the circulation flow path.

  Next, a second embodiment of the present invention will be described with reference to FIGS. FIG. 8 is an explanatory cross-sectional view of a main part for explaining the embodiment, and FIG. 9 is an explanatory plan view of the nozzle plate. 10 is a plan view of the first flow path plate, FIG. 11 is a plan view of the second flow path plate, and FIG. 12 is a plan view of the third flow path plate. 13 is a plan view of the fourth flow path plate, FIG. 14 is a plan view of the fifth flow path plate, and FIG. 15 is a plan view of the sixth flow path plate. FIG. 16 is a plan view of the diaphragm member, and FIG. 17 is a plan view of the frame member.

  In the present embodiment, the channel plate 2 is configured by laminating six plate-like members (layer members) of the first channel plate 51 to the sixth channel plate 56. Specifically, the first flow path plate 51 to the sixth flow path plate 56 are laminated in this order from the nozzle plate 1 side to form the flow path plate 2, and the diaphragm member 3 is laminated on the sixth flow path plate 56. Further, a frame member 20 is laminated on the diaphragm member 3.

  As shown in FIG. 9, the nozzle plate 1 is provided with a nozzle 4 for discharging a liquid. In this case, there are two nozzle rows 4A and 4B in which the nozzles 4 are arranged, that is, a total of four nozzle rows.

  As shown in FIG. 10, the first flow path plate 51 is formed with a through hole 5 a that forms the passage 5 and a through groove 42 a that forms a flow path including the circulation resistance part 42.

  As shown in FIG. 11, the second flow path plate 52 is formed with a through hole 5 b forming the passage 5 and a through groove 41 a forming the circulation flow path 41.

  As shown in FIG. 12, the third flow path plate 53 is formed with a through hole 5 c that forms the passage 5 and a through groove 44 a that forms the bridge flow path 44.

  As shown in FIG. 13, the fourth flow path plate 54 is formed with a through hole 6 a that forms the individual liquid chamber 6 and a through groove 44 b that forms the bridge flow path 44.

  As shown in FIG. 14, the fifth flow path plate 55 includes a through hole 6b that forms the individual liquid chamber 6, the fluid resistance part 7, and the liquid introduction part 8, and a through groove part 44c that forms the bridge flow path 44. Is formed.

  As shown in FIG. 15, the sixth flow path plate 56 has a through hole 6 c that forms the individual liquid chamber 6, a through hole 6 d that forms the liquid introduction part 8, and a through groove part that forms the bridge flow path 44. 44d are formed.

  As shown in FIG. 16, the diaphragm member 3 has a through groove 9 a forming the opening 9 and an opening 46 communicating with the circulation port 43.

  As shown in FIG. 17, the frame member 20 has two sets of recesses 10a and 10b forming two common liquid chambers 10, a supply port 23 communicating with the two common liquid chambers 10A and 10B, and two circulating flows. A circulation port 43 leading to the passage 41 is formed.

  Further, the supply ports 23 are provided at both ends in the nozzle arrangement direction, and are configured to supply the two common liquid chambers 10 from both sides.

  Further, a through groove 24 for inserting the piezoelectric actuator 11 is formed between the two common liquid chambers 10A and 10B.

  As described above, the members forming the circulation flow channel 41 and the cross-linking flow channel 44 are formed by stacking a plurality of layer members (plate-like members), so that the height of the circulation flow channel 41 ( (The height in the thickness direction of the member).

  Thereby, the flow path cross-sectional area of the circulation flow path 41 can be increased, and pressure loss can be suppressed.

  Further, since the supply port 23 and the circulation port 43 are arranged at both ends in the nozzle arrangement direction, the circulation port can be arranged without increasing the outer shape of the head.

  In this case, the supply port 23 leading to the common liquid chamber 10 and the cross-linking passage 44 passing through the circulation passages 41A and 41B are configured to supply and discharge from both sides.

  As a result, the pressure loss difference can be reduced to about 1/4, and the dimensions of the common liquid chamber and the circulation channel can be reduced, as compared with the case where the supply and circulation are performed from one side. The size of the head can be reduced.

  Next, a third embodiment of the present invention will be described with reference to FIGS. FIG. 18 is an explanatory plan view of a diaphragm member for explaining the embodiment, and FIG. 19 is an explanatory plan view of a frame member.

  In the present embodiment, the common liquid chambers 10a and 10b corresponding to the respective nozzle rows have a single-side supply configuration in which the liquid is supplied from a supply port 23 disposed at one end in the nozzle arrangement direction as an independent configuration.

  Thereby, the length of the head in the longitudinal direction can be made shorter than in the first embodiment.

  Next, a fourth embodiment of the present invention will be described with reference to FIGS. FIG. 20 is a cross-sectional explanatory view for explaining the same embodiment, FIG. 21 is a cross-sectional explanatory view along the line DD of FIG. 20, FIG. 22 is a nozzle plate-side plan explanatory view of the flow path plate, and FIG. FIG. 5 is an explanatory plan view of a flow path plate on a diaphragm member side.

  In the flow path plate 2, a through groove serving as a circulation flow path 41, a groove serving as a flow path 47 including the circulation resistance part 42, and a groove serving as a bridge flow path 44 are formed. The channel plate 2 is formed with a groove serving as an individual liquid chamber 6, a fluid resistance part 7, and a liquid introduction part 8, and a through hole serving as a passage 5.

  Here, the flow channel plate 2 is formed of a silicon substrate, the through groove portion serving as the circulation flow channel 41 and the through hole serving as the passage 5 are formed by full etching penetrating in the thickness direction, and the individual liquid chamber 6 and the fluid resistance portion 7 are formed. The groove serving as the liquid introduction part 8 and the groove serving as the cross-linking flow path 44 are formed by half etching.

  In the present embodiment, the cross-linking flow path 44 is disposed at the same position (position included in the circulation flow path) as the circulation flow path 41 in the thickness direction of the flow path plate 2. The cross-sectional area is smaller than the cross-sectional area of the circulation channel 41.

  Accordingly, the flow path plate can be formed with a simple configuration, and the height of the circulation flow path 41 (height in the thickness direction of the member) can be secured with the simple configuration. The cross-sectional area can be increased, and the pressure loss can be suppressed.

  Next, an example of a device for discharging a liquid according to the present invention including the liquid discharging unit according to the present invention will be described with reference to FIGS. FIG. 24 is an explanatory side view of a mechanism of the apparatus, and FIG. 25 is an explanatory plan view of a main part of the mechanism.

  The device that discharges this liquid is a serial type image forming device. The carriage 433 is held so as to be able to reciprocate in the main scanning direction (the direction of the arrow) by main and slave guide rods 431 and 432 which are guide members transversely mounted on the left and right side plates 421A and 421B.

  The carriage 433 includes two liquid ejection units 430 (430A, 430A, 430A, 430A, and 430) according to the present invention in which a liquid discharge head 434 according to the present invention and a head tank (sub tank) 435 that supplies liquid to the liquid discharge head 434 are integrated. 430B). The liquid ejection head 434 is mounted with a nozzle row including a plurality of nozzles in a sub-scanning direction orthogonal to the main scanning direction, with the liquid ejection direction facing downward.

  Here, the liquid ejection head 434 has two nozzle rows. One nozzle row of the liquid ejection head 434 of one liquid ejection unit 430A ejects black (K) liquid, and the other nozzle row ejects cyan (C) liquid.

  Further, one nozzle row of the liquid ejection head 434 of the other liquid ejection unit 430B ejects magenta (M) liquid, and the other nozzle row ejects yellow (Y) liquid.

  Here, the configuration is such that two liquid ejection heads are used to eject four colors of liquid. However, four nozzle rows are arranged in one liquid ejection head, and four colors of liquid are ejected from one liquid ejection head. Each color can also be ejected.

  The “integration” in the liquid ejection units 430A and 430B is that the liquid ejection head 434 and the head tank 435 are fixed to each other directly or via a filter member or the like by a fastening member or an adhesive, or , Are connected to each other by a tube or the like.

  A main tank 410 (410k, 410c, 201m, 210y) as a liquid cartridge of each color is detachably mounted on the cartridge holder 404 on the apparatus main body side. Then, the liquid of each color is sent from the main tank 410 of each color to the head tank 435 of each of the liquid discharge units 430A and 430B via the supply tube 436 of each color by the liquid sending unit 424 including the liquid sending pump.

  On the other hand, as a paper feeding unit for feeding the paper 442 stacked on the paper stacking unit (pressing plate) 441 of the paper feeding tray 402, a half-moon roller (feeding) that separates and feeds the sheets 442 one by one from the paper stacking unit 441. (Paper roller) 443 and a separation pad 444 facing the paper feed roller 443.

  A guide 445 that conveys and guides the fed sheet 442, a counter roller 446, a conveyance guide member 447, and a pressing member 448 having a front end pressing roller 449 is provided. Further, a transport belt 451 is provided as transport means for adsorbing the transported paper 442 and transporting the transported paper at a position facing the liquid discharge head 434 of the liquid discharge unit 430.

  Here, the transport belt 451 is an endless belt, is stretched between the transport roller 452 and the tension roller 453, and is configured to orbit in the belt transport direction (sub-scanning direction). Here, an electrostatic transport belt charged by a charging roller 456 serving as a charging unit is used as the transport belt 451. However, the transport belt 451 may be a transport belt that sucks by air suction. Further, as the conveying means, a conveying means using two rollers without using a conveying belt may be used.

  A separation claw 461 for separating the sheet 442 from the transport belt 451, a discharge roller 462, and a discharge roller 463 are provided downstream of the tension roller 453 around which the transport belt 451 is wound. A paper discharge tray 403 is provided below.

  A double-sided unit 471 is detachably mounted on the back of the apparatus main body. The double-sided unit 471 takes in the paper 442 returned by the reverse rotation of the transport belt 451, reverses the paper 442, and feeds the paper 442 again between the counter roller 446 and the transport belt 451. The upper surface of the duplex unit 471 is a manual tray 472.

  Further, a maintenance / recovery mechanism 481 for maintaining and recovering the state of the nozzles of the liquid ejection heads 434 of the liquid ejection units 430A and 430B is arranged in a non-printing area on one side of the carriage 433 in the scanning direction.

  The maintenance and recovery mechanism 481 includes caps 482a and 482b for capping the nozzle surface of the liquid ejection head 434. The maintenance and recovery mechanism 481 includes a blade member 483 for wiping the nozzle surface. The maintenance / recovery mechanism 481 includes a blank discharge receiver 484 that receives a liquid when performing a blank discharge that discharges a liquid that does not contribute to image formation in order to discharge the thickened liquid.

  In the non-printing area on the other side of the carriage 433 in the scanning direction, an idle discharge receiver 488 for receiving liquid when performing idle discharge during image formation or the like is arranged. The idle discharge receiver 488 has an opening 489 and the like along the nozzle row direction of the liquid discharge head 434.

  In this image forming apparatus, the paper 442 is separated and fed one by one from the paper feed tray 402, and the paper 442 fed substantially vertically upward is guided by a guide 445, and is moved between the transport belt 451 and the counter roller 446. It is transported sandwiched between. Further, the leading end of the sheet 442 is guided by the carrying guide 437 and pressed against the carrying belt 451 by the leading end pressing roller 449, so that the carrying direction is changed by approximately 90 °.

  Then, when the sheet 442 is fed onto the charged conveyance belt 451, the sheet 442 is attracted to the conveyance belt 451, and the sheet 442 is conveyed in the sub-scanning direction by the orbital movement of the conveyance belt 451.

  Therefore, by driving the liquid discharge heads 434 of the liquid discharge units 430A and 430B according to the image signal while moving the carriage 433, the liquid is discharged onto the stopped paper 442 to record an image of one line. . Then, after the sheet 442 is conveyed by a predetermined amount, image formation for the next line is performed. Upon receiving a recording end signal or a signal indicating that the rear end of the sheet 442 has reached the recording area, the recording operation is terminated, and the sheet 442 is discharged to the discharge tray 403.

  As described above, since the image forming apparatus includes the liquid discharge head or the liquid discharge head unit according to the present invention, a high-quality image can be stably formed.

  In the present application, the “device that discharges liquid” is a device that can discharge liquid to an object to which liquid can adhere.

  This “device for discharging liquid” includes not only a portion for discharging liquid but also a device to which liquid is attached. Means related to feeding, transporting and discharging, and other devices referred to as pre-processing devices and post-processing devices And the like.

  In addition, the “apparatus for ejecting liquid” includes conventional apparatuses such as a recording apparatus, a printing apparatus, an image forming apparatus, a droplet ejection apparatus, a liquid ejection apparatus, a processing liquid application apparatus, and a three-dimensional printing apparatus. It is.

  In addition, the “device that discharges liquid” is not limited to a device in which a significant image such as a character or a figure is visualized by the liquid adhering to a liquid adhering object. For example, those that form patterns or the like that have no meaning in themselves and those that form three-dimensional images are also included.

  The above-mentioned "thing to which liquid adheres" means a thing to which liquid can adhere even temporarily. When an alternative term such as paper, medium, recording medium, recording medium, recording paper, recording paper, powder layer (powder layer) is used in place of the term "thing to which liquid adheres", The term is intended to include all liquids to which they adhere unless otherwise specified.

  The material to which the liquid adheres may be paper, thread, fiber, cloth, leather, metal, plastic, glass, wood, ceramics, etc. as long as the liquid can be adhered even temporarily.

  “Liquid” also includes inks, processing liquids, DNA samples, resists, pattern materials, binders, and the like.

  Further, the “device that discharges liquid” includes both a serial type device that moves a liquid discharge head and a line type device that does not move a liquid discharge head, unless otherwise specified.

  Further, the “liquid ejection unit” means an integrated unit for ejecting a liquid. For example, the “liquid ejection unit” includes a unit in which the configuration of a head tank, a carriage, a supply mechanism, a maintenance mechanism, and a main scanning movement mechanism is arbitrarily combined with a liquid ejection head.

  For example, the “liquid ejection unit” includes an integrated liquid ejection head and a head tank described in the above embodiment, an integrated liquid ejection head and a carriage, and an integrated liquid ejection head, a head tank, and a carriage. Things included.

  In addition, those in which a filter unit (in which the above-described filter member and the distribution channel are formed) are added to these liquid discharge units are included.

  In addition, those that integrate the liquid ejection head and the maintenance mechanism, those that integrate the liquid ejection head, the maintenance mechanism, and the main scanning movement mechanism, those that integrate the liquid ejection head, the main scanning movement mechanism, and the supply mechanism are also included. It is.

  The main scanning movement mechanism is configured by a carriage, a guide member for guiding the carriage, or a combination thereof with a driving source and a carriage movement mechanism. The supply mechanism includes a loading section for mounting the main tank, a tube, a head tank, and the like. The maintenance mechanism is a combination of any two or more of a cap, a wiper member, a suction means such as a suction pump connected to the cap, and an idle discharge receiver.

  Further, the “liquid ejection unit” includes a unit configured by a part excluding a mechanism for transporting a unit to which a liquid adheres from the mechanism unit described in the above embodiment.

  Further, the "liquid ejection head" is not limited to the pressure generating means used. For example, in addition to the piezoelectric actuator described in the above embodiment, a thermal actuator using an electrothermal conversion element such as a heating resistor, an electrostatic actuator including a diaphragm and a counter electrode, or the like may be used.

  Further, image forming, recording, printing, printing, printing, molding, and the like in the terms of the present application are all synonyms.

Reference Signs List 1 nozzle plate 2 flow path plate 3 diaphragm member 4 nozzle 5 passage 6 individual liquid chamber 10, 10A, 10B common liquid chamber 11 piezoelectric actuator 12 piezoelectric member 20 frame member 41, 41A, 41B circulation flow path 42 circulation resistance section 434 liquid Discharge head 430 Liquid discharge unit

Claims (9)

At least two nozzle rows in which a plurality of nozzles for discharging liquid are arranged;
A plurality of individual liquid chambers communicating with each nozzle of the nozzle row,
A common liquid chamber that supplies the liquid to the plurality of individual liquid chambers,
Having at least two circulation channels communicating with each of the plurality of individual liquid chambers and collecting the liquid,
The circulation flow path is disposed on the same side as the common liquid chamber with respect to the nozzle in a direction orthogonal to the nozzle arrangement direction and the liquid discharge direction,
The two circulation channels communicate with each other via a bridge channel arranged in a direction crossing the nozzle arrangement direction,
The cross-linking channel and the circulation channel are arranged at different positions in the thickness direction of a member forming the cross-linking channel and the circulation channel,
The circulation channel is formed in a first channel member,
The bridge channel is formed in a second channel member,
A liquid discharge head, wherein the circulation channel and the bridge channel are connected by overlapping the first channel member and the second channel member. At least two nozzle rows in which a plurality of nozzles for discharging liquid are arranged;
A plurality of individual liquid chambers communicating with each nozzle of the nozzle row,
A common liquid chamber that supplies the liquid to the plurality of individual liquid chambers,
Having at least two circulation channels communicating with each of the plurality of individual liquid chambers and collecting the liquid,
The circulation flow path is disposed on the same side as the common liquid chamber with respect to the nozzle in a direction orthogonal to the nozzle arrangement direction and the liquid discharge direction,
The two circulation channels communicate with each other via a bridge channel arranged in a direction crossing the nozzle arrangement direction,
The bridge channel and the circulation channel are arranged so as to overlap in a thickness direction of a member forming the bridge channel and the circulation channel,
The circulation channel is formed in a first channel member,
The bridge channel is formed in a second channel member,
A liquid discharge head, wherein the circulation channel and the bridge channel are connected by overlapping the first channel member and the second channel member. At least two nozzle rows in which a plurality of nozzles for discharging liquid are arranged;
A plurality of individual liquid chambers communicating with each nozzle of the nozzle row,
A common liquid chamber that supplies the liquid to the plurality of individual liquid chambers,
Having at least two circulation channels communicating with each of the plurality of individual liquid chambers and collecting the liquid,
The circulation flow path is disposed on the same side as the common liquid chamber with respect to the nozzle in a direction orthogonal to the nozzle arrangement direction and the liquid discharge direction,
The two circulation channels communicate with each other via a bridge channel arranged in a direction crossing the nozzle arrangement direction,
The cross-linking flow path and the circulation flow path are arranged so as to overlap when viewed from a discharge direction of the liquid,
The circulation channel is formed in a first channel member,
The bridge channel is formed in a second channel member,
A liquid discharge head, wherein the circulation channel and the bridge channel are connected by overlapping the first channel member and the second channel member. 4. The liquid discharge head according to claim 1, wherein the cross-sectional area of the cross-linking channel is smaller than the cross-sectional area of the circulation channel. The cross-linking flow path and the circulation flow path are arranged such that a central axis passing through the center in the flow path cross-section of the cross-linking flow path and a central axis passing through the center in the flow path cross-section of the circulation flow path are three-dimensionally crossed. The liquid ejection head according to claim 1, wherein A supply port leading to the common liquid chamber;
A circulation port communicating with the cross-linking channel,
The liquid ejection head according to claim 1, wherein the supply port and the circulation port are arranged at an end in a nozzle arrangement direction. The two common liquid chambers corresponding to the nozzle rows communicate with each other,
7. The liquid ejection head according to claim 1, wherein supply ports communicating with the common liquid chamber are arranged at both ends in a nozzle arrangement direction. A liquid discharge unit comprising the liquid discharge head according to claim 1. An apparatus for discharging a liquid, comprising: the liquid discharge head according to claim 1; or the liquid discharge unit according to claim 8.

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