Liquid dispensing head, head unit, and liquid dispensing device

Abstract

We propose a liquid dispensing head configuration that can suppress deviations in the liquid's landing position. [Solution] A liquid discharge head 20 that discharges liquid while moving includes a nozzle for discharging liquid and a housing 21 having a liquid flow path inside for supplying liquid to the nozzle. If the width direction is defined as the direction perpendicular to the movement directions X1 and X2 of the liquid discharge head 20 along the nozzle surface 31a where the nozzle opens, then the surfaces 21a and 21b of the housing 21 facing the movement directions X1 and X2 are inclined with respect to the movement directions X1 and X2, and are configured to protrude toward the movement directions X1 and X2 more towards the center than toward both ends in the width direction.

Description

Technical Field

[0001] The present invention relates to a liquid ejection head, a head unit, and a liquid ejection device.

Background Art

[0002] As an example of a liquid ejection device that ejects a liquid, an inkjet type image forming device that forms an image by ejecting liquid ink onto a sheet such as paper is known.

[0003] Generally, an inkjet type image forming device includes a liquid ejection head having a plurality of nozzles that eject a liquid (ink). In addition, as a liquid ejection head mounted on the image forming device, there is a so-called serial type liquid ejection head that ejects a liquid (ink) while moving, and a so-called line type liquid ejection head that ejects a liquid (ink) without moving.

[0004] In particular, in the case of a serial type liquid ejection head, there is a problem that the landing position of the liquid is shifted due to an air flow generated when the liquid ejection head moves.

[0005] Regarding such a problem, in Patent Document 1 (Japanese Patent Application Laid-Open No. 2004-42580), a technique has been proposed in which the surfaces on both sides in the moving direction of a carriage on which an inkjet recording head is mounted are formed in a streamline shape to reduce air resistance and reduce air turbulence (turbulent flow) generated during movement.

[0006] However, in Patent Document 1, although a configuration of the carriage for reducing air turbulence has been proposed, a configuration of the liquid ejection head itself that is affected by the air flow has not been proposed.

Summary of the Invention

Problems to be Solved by the Invention

[0007] Therefore, the objective of this invention is to propose a liquid discharge head configuration that can suppress deviations in the liquid's landing position. [Means for solving the problem]

[0008] To solve the above problems, the present invention provides a liquid discharge head that discharges liquid while moving, comprising a nozzle for discharging liquid and a housing having a liquid channel for supplying liquid to the nozzle, wherein, if the width direction is defined as the direction perpendicular to the direction of movement of the liquid discharge head along the nozzle surface in which the nozzle opens, the surface of the housing facing the direction of movement is inclined with respect to the direction of movement and is configured to protrude in the direction of movement more towards the center than at both ends in the width direction. [Effects of the Invention]

[0009] According to the present invention, it is possible to provide a liquid dispensing head configuration that can suppress deviations in the point of impact of the liquid. [Brief explanation of the drawing]

[0010] [Figure 1] This is a schematic diagram showing the overall configuration of an inkjet-type image forming apparatus, which is an example of a liquid ejection device to which the present invention is applied. [Figure 2] This is a block diagram showing a control system for an image forming apparatus according to the first embodiment of the present invention. [Figure 3] This is a plan view of a head unit according to the first embodiment of the present invention. [Figure 4] This is a perspective view of the liquid dispensing head according to the first embodiment of the present invention. [Figure 5] This is a perspective view showing the internal structure of a liquid discharge head according to the first embodiment of the present invention. [Figure 6] This is an exploded perspective view of the internal components of a liquid dispensing head according to the first embodiment of the present invention. [Figure 7] This is an external perspective view illustrating the characteristic parts of a liquid dispensing head according to the first embodiment of the present invention. [Figure 8] This is a plan view of the liquid discharge head according to the first embodiment of the present invention, as seen from the cover member side. [Figure 9] This is a side view of a liquid discharge head according to the first embodiment of the present invention, as seen from the width direction. [Figure 10] This figure shows the configuration of a liquid discharge head according to a second embodiment of the present invention, where (a) is an external perspective view of the liquid discharge head, (b) is a plan view of the liquid discharge head as seen from the cover member side, (c) is a front view of the liquid discharge head as seen from the direction of movement, and (d) is a side view of the liquid discharge head as seen from the width direction. [Figure 11] This figure shows the configuration of a liquid discharge head according to a third embodiment of the present invention, where (a) is an external perspective view of the liquid discharge head, (b) is a plan view of the liquid discharge head as seen from the cover member side, (c) is a front view of the liquid discharge head as seen from the direction of movement, and (d) is a side view of the liquid discharge head as seen from the width direction. [Figure 12] This figure shows the configuration of a liquid discharge head according to a fourth embodiment of the present invention, where (a) is an external perspective view of the liquid discharge head, (b) is a plan view of the liquid discharge head as seen from the cover member side, (c) is a front view of the liquid discharge head as seen from the direction of movement, and (d) is a side view of the liquid discharge head as seen from the width direction. [Figure 13] This figure shows the configuration of a liquid discharge head according to a fifth embodiment of the present invention, where (a) is an external perspective view of the liquid discharge head, (b) is a plan view of the liquid discharge head as seen from the cover member side, (c) is a front view of the liquid discharge head as seen from the direction of movement, and (d) is a side view of the liquid discharge head as seen from the width direction. [Figure 14] This is an external perspective view of a liquid dispensing head according to the sixth embodiment of the present invention. [Figure 15] This is an external perspective view of the liquid discharge head 20 according to the seventh embodiment of the present invention. [Figure 16] This figure shows an example in which the present invention can be applied to a discharge head that discharges liquid in either the forward or return direction of movement. [Figure 17] This is a schematic diagram showing the overall configuration of an electrode manufacturing apparatus to which the present invention can be applied. [Figure 18]It is an external perspective view of a liquid ejection head according to a comparative example. [Figure 19] It is a side view of a liquid ejection head according to another comparative example as viewed from the width direction.

Embodiments for Carrying out the Invention

[0011] Hereinafter, the present invention will be described based on the accompanying drawings. In each of the drawings for explaining the present invention, components such as members and components having the same function or shape are given the same reference numerals as long as they can be distinguished, and the description thereof will be omitted after being explained once.

[0012] <Overall Configuration of Image Forming Apparatus> FIG. 1 is a schematic view showing the overall configuration of an inkjet type image forming apparatus which is an example of a liquid ejection apparatus to which the present invention is applied.

[0013] First, while referring to FIG. 1, the overall configuration of an inkjet type image forming apparatus according to the first embodiment of the present invention will be described.

[0014] As shown in FIG. 1, an image forming apparatus 100 according to the first embodiment of the present invention includes a sheet supply unit 1 that supplies a sheet S on which an image is to be formed, a conveyance unit 2 that conveys the sheet S supplied from the sheet supply unit 1, an image forming unit 3 that forms an image on the sheet S, a drying unit 4 that dries the sheet S, and a sheet recovery unit 5 that recovers the sheet S on which the image has been formed.

[0015] The sheet supply unit 1 is provided with a supply roller 11 around which a long sheet S is wound in a roll shape, and a tension adjustment mechanism 12 that adjusts the tension applied to the sheet S. The supply roller 11 is configured to be rotatable in the direction of the arrow in FIG. 1, and when the supply roller 11 rotates, the sheet S is fed out. The tension adjustment mechanism 12 has a plurality of adjustment rollers that span the sheet S and apply tension. By changing the distance between the adjustment rollers, the tension of the sheet S is adjusted, and the sheet S is supplied with a constant tension.

[0016] The transport unit 2 is equipped with multiple transport rollers 15 and other means for transporting the sheet S. When the sheet S is supplied from the sheet supply unit 1 to the transport unit 2, the sheet S is transported to the image forming unit 3 by the multiple transport rollers 15.

[0017] The image forming unit 3 includes a head unit 13 having multiple liquid ejection heads for ejecting liquid ink onto a sheet S, and a platen 14 as a sheet support member for supporting the conveyed sheet S. The sheet S, which has been conveyed by the conveyor rollers 15, passes below the head unit 13 while being supported by the platen 14. At this time, ink is ejected from the head unit 13 onto the sheet S, forming an image on the sheet S.

[0018] The drying section 4 is equipped with a heating drum 16 and other heating means for heating the sheet S. The heating drum 16 is a cylindrical heating element that houses a heating source such as a halogen heater inside. When the sheet S, on which an image has been formed in the image forming section 3, is transported to the drying section 4, the sheet S is heated by contact with the outer surface of the heating drum 16, and the sheet S is dried. In addition to the heating drum 16 and other contact-type heating means, the heating means for heating the sheet S may also be non-contact-type heating means such as a hot air generator that blows hot air onto the sheet S.

[0019] The sheet retrieval unit 5 is equipped with a retrieval roller 17 for winding up and retrieving the sheet S, and a tension adjustment mechanism 18 for adjusting the tension applied to the sheet S. The retrieval roller 17 is configured to rotate in the direction of the arrow in Figure 1, and as the retrieval roller 17 rotates, the sheet S is wound up into a roll and retrieved. The tension adjustment mechanism 18 has multiple adjustment rollers, similar to the tension adjustment mechanism 12 of the sheet supply unit 1. By changing the distance between the adjustment rollers, the tension of the sheet S is adjusted, and the sheet S is wound up with a constant tension and retrieved by the retrieval roller 17.

[0020] Figure 2 is a block diagram showing the control system of an image forming apparatus according to the first embodiment of the present invention.

[0021] As shown in Figure 2, the image forming apparatus 100 according to the first embodiment of the present invention includes a sheet supply unit 1, a transport unit 2, an image forming unit 3, a drying unit 4, and a sheet recovery unit 5, as well as a control unit 6 that controls these units.

[0022] The control unit 6 is composed of an information processing device such as a PC (Personal Computer). The control unit 6 generates image data of the image to be formed on the sheet S, and also controls various operations of the sheet supply unit 1, transport unit 2, image forming unit 3, drying unit 4, and sheet recovery unit 5. For example, the control unit 6 controls the ink ejection operation of the head unit 13, the rotation speed of the supply roller 11, recovery roller 17, and each transport roller 15, and the heating temperature of the heating drum 16. Furthermore, an image is formed on the sheet S by ejecting ink from the head unit 13 onto the sheet S based on the image data generated by the control unit 6.

[0023] <Head unit configuration> Next, the configuration of the head unit 13 according to the first embodiment of the present invention will be described based on Figure 3.

[0024] Figure 3 is a plan view of the head unit 13 according to the first embodiment of the present invention.

[0025] The head unit 13 in Figure 3 is a so-called serial type head unit that ejects ink onto the sheet S while reciprocating in the direction of the arrow X in the figure (a direction perpendicular to the sheet transport direction Y), which is the main scanning direction relative to the sheet S. This head unit 13 includes a carriage 62 on which multiple liquid ejection heads 20 are mounted, a guide member (guide rod) 63 for guiding the carriage 62 in the main scanning direction X, and a drive device 64 for moving the carriage 62. The liquid ejection heads 20 have multiple nozzles 30 for ejecting liquid.

[0026] The drive unit 64 includes, for example, a motor 65 which is a drive source, and a timing belt 68 wrapped around a drive pulley 66 and a driven pulley 67. When the motor 65 is driven and the drive pulley 66 rotates, the timing belt 68 rotates, causing the carriage 62 to move along the guide member 63 in the main scanning direction X. Also, by switching the rotation direction of the motor 65 between one direction and the opposite direction, the carriage 62 moves back and forth in the main scanning direction X.

[0027] As shown in Figure 3, the sheet S is transported in the direction of arrow Y, and when the sheet S reaches a predetermined image formation position, the transport of the sheet S is temporarily stopped. Then, the carriage 62 moves back and forth in the main scanning direction X, and liquid (ink) is ejected from the liquid ejection head 20. As a result, an image of a predetermined width is formed on the stationary sheet S. Subsequently, the intermittent transport (transport and stop) of the sheet S in the direction of arrow Y and the liquid ejection operation accompanying the reciprocating movement of the carriage 62 in the main scanning direction X are repeated, and images are sequentially formed on the sheet S.

[0028] <Challenges related to deviations in the impact point of liquids> Here, we will explain the issue of deviation in the liquid's impact point based on the comparative example shown in Figure 18.

[0029] As shown in Figure 18, the liquid discharge head 200 according to the comparative example comprises a rectangular parallelepiped housing 201 and a cover member 202 that is taller than the housing 201 as its exterior. The housing 201 is provided with a liquid flow path that communicates with the nozzle. On the other hand, the cover member 202 houses a discharge operation control unit, such as a drive IC, which controls the discharge operation of discharging liquid from the nozzle.

[0030] In the comparative example of this configuration, when the liquid is discharged, if the liquid discharge head 200 moves in the direction of arrow X1 in Figure 18, for example, air hits the surfaces 201a and 202a of the housing 201 and cover member 202 facing the direction of movement X1. As shown by the dashed arrows in the figure, the air is pushed up and down and left and right, and a vortex airflow is generated near the nozzle surface located on the lower side of the housing 201 in Figure 18. This causes problems such as the liquid's landing position shifting due to the influence of this airflow. In particular, as in the comparative example, if the surface 201a of the housing 201 facing the direction of movement X1 and the surface 202a of the cover member 202 facing the direction of movement X1 are both perpendicular to the direction of movement X1, the air resistance when the liquid discharge head 200 moves increases, so the airflow generated by the pushed air also increases, and a shift in the liquid's landing position tends to occur.

[0031] Therefore, the present invention proposes a liquid discharge head configuration that suppresses the airflow generated when the liquid discharge head moves, thereby suppressing the displacement of the liquid's landing position due to the influence of the airflow. The configuration of the liquid discharge head according to the first embodiment of the present invention will be described below.

[0032] <Configuration of the liquid dispensing head> First, the basic configuration of the liquid discharge head according to the first embodiment of the present invention will be described based on Figures 4 to 6.

[0033] Figure 4 is an external perspective view of the liquid discharge head 20 according to the first embodiment of the present invention, and Figure 5 is a perspective view showing the internal structure of the liquid discharge head 20 according to the first embodiment of the present invention. Figure 6 is an exploded perspective view of the internal components of the liquid discharge head 20 according to the first embodiment of the present invention.

[0034] As shown in Figure 4, the liquid discharge head 20 according to the first embodiment of the present invention, like the comparative example above, comprises a rectangular parallelepiped housing 21 and a cover member 22 that is taller than the housing 21 as its exterior.

[0035] The housing 21 contains a liquid channel for supplying liquid to the nozzle, as well as a piezoelectric element as a pressure generating element for generating pressure to discharge the liquid. Meanwhile, the cover member 22 houses a drive IC as a discharge operation control unit that controls the discharge operation of liquid discharged from the nozzle, and a flexible printed circuit board (FPC) that transmits drive signals from the drive IC.

[0036] As shown in Figure 5, the drive ICs 23 are mounted on the flexible circuit board 24 and arranged inside the cover members 22 so that they face each other. Note that only a portion of the cover members 22 is shown in Figure 5.

[0037] As shown in Figure 6, the housing 21 is assembled with a nozzle plate 31, a flow path substrate 32, a diaphragm member 33, a piezoelectric element 34, and a base member 35. The nozzle plate 31 is a member through which multiple nozzles 30 open and is positioned facing the sheet being conveyed. In Figure 6, the nozzle plate 31 is positioned at the top of the internal components, but the nozzle plate 31 is positioned on the lower side of the housing 21 as shown in Figures 4 and 5. Therefore, the lower side of the housing 21 in Figures 4 and 5 is provided with a nozzle surface 31a through which the nozzles 30 open.

[0038] The flow channel substrate 32 is provided with multiple individual flow channels 25 that communicate individually with multiple nozzles 30. The individual flow channels 25 also serve as individual liquid chambers for storing the liquid discharged from the nozzles 30.

[0039] The diaphragm member 33 is made of a deformable sheet member. A piezoelectric element 34, which is held and supported by a base member 35, is positioned to be in contact with the diaphragm member 33. The piezoelectric element 34 is, for example, a member made of alternating layers of piezoelectric layers and internal electrodes, and a flexible wiring board 24 (see Figure 5) is connected to the internal electrodes via external electrodes. When a drive signal from the drive IC 23 is transmitted to the piezoelectric element 34 via the flexible wiring board 24, the piezoelectric element 34 expands and contracts, causing the diaphragm member 33 to deform, and the liquid in the individual flow channels 25 (individual liquid chambers) to be pressurized and discharged from the nozzle 30.

[0040] The housing 21 is provided with a common channel 26 that serves as a liquid channel communicating with a plurality of individual channels 25. When liquid is supplied into the common channel 26, the liquid is supplied to each individual channel 25 via a supply port 27 provided in the diaphragm member 33. Then, as the piezoelectric element 34 expands and contracts, the diaphragm member 33 deforms, pressurizing the liquid in the individual channels 25 (individual liquid chambers) and causing it to be discharged from the nozzle 30.

[0041] Next, the characteristic features of the liquid discharge head 20 according to the first embodiment of the present invention will be described.

[0042] As described above, in the first embodiment of the present invention, when liquid (ink) is ejected from the liquid ejection head 20 onto the sheet, the liquid ejection head 20 reciprocates in the main scanning direction. Figure 7 shows the relationship between the direction of movement of the liquid ejection head 20 and the orientation of the liquid ejection head 20 according to the first embodiment of the present invention.

[0043] As shown in Figure 7, in the first embodiment of the present invention, the liquid discharge head 20 moves back and forth in the direction of arrow X1, which is one direction of the main scanning direction, and in the direction of arrow X2, which is opposite to it. Therefore, on the opposite surfaces of the liquid discharge head 20 facing the movement directions X1 and X2, a considerable amount of airflow is generated as air strikes them as they move. For this reason, in the first embodiment of the present invention, the surfaces 21a and 21b of the housing 21 facing the movement directions X1 and X2 (surfaces facing opposite directions) are made into protruding curved surfaces that project toward the respective movement directions X1 and X2.

[0044] More specifically, as shown in Figure 8, a plan view of the liquid discharge head 20 as seen from the cover member 22 side, of the two opposing movement directions X1 and X2, the surface 21a of the housing 21 facing one movement direction X1 is configured as a protruding curved surface that projects in that movement direction X1, and the surface 21b of the housing 21 facing the other movement direction X2 is configured as a protruding curved surface that projects in that movement direction X2. Furthermore, if the direction perpendicular to the movement directions X1 and X2 of the liquid discharge head 20 along the nozzle surface 31a is defined as the "width direction W", then the respective surfaces 21a and 21b of the housing 21 facing the movement directions X1 and X2 are curved inclined with respect to the movement directions X1 and X2, and are configured to protrude in the movement directions X1 and X2 closer to the center than to both ends of the width direction W.

[0045] Thus, in the liquid discharge head 20 according to the first embodiment of the present invention, the surfaces 21a and 21b of the housing 21 facing the movement directions X1 and X2 are configured as protruding curved surfaces that project toward the respective movement directions X1 and X2, thereby suppressing the generation of airflow when the liquid discharge head 20 moves. That is, when the liquid discharge head 20 moves, even if air hits the surfaces 21a and 21b facing the movement directions X1 and X2 at that time, the air is smoothly guided along the protruding curved surfaces (surfaces 21a and 21b facing the movement directions X1 and X2) toward both ends of the width direction W as shown by the dashed arrows in Figure 7. Therefore, compared to the case where air hits a surface perpendicular to the movement direction, as in the comparative example, air resistance is reduced and the generation of airflow due to displaced air is suppressed. As a result, in the first embodiment of the present invention, it is possible to suppress the displacement of the liquid's landing position due to the influence of airflow generated near the nozzle surface 31a. In Figure 7, only the airflow when the liquid discharge head 20 moves in one direction X1 is shown by the dashed arrow. However, even when the liquid discharge head 20 moves in the opposite direction X2, the air is smoothly guided to both ends of the width direction W by the surface 21b facing the direction of movement X2. This suppresses the generation of airflow near the nozzle surface 31a and reduces the displacement of the liquid's landing position due to the influence of airflow.

[0046] In the first embodiment of the present invention, as shown in Figure 9, when the housing 21 is viewed from the width direction W, the surfaces 21a and 21b facing the movement directions X1 and X2 are arranged to be perpendicular or nearly perpendicular to the movement directions X1 and X2. That is, in the first embodiment of the present invention, the surfaces 21a and 21b of the housing 21 facing the movement directions X1 and X2 are not curved or inclined surfaces that inclin to approach the nozzle surface 31a in the opposite direction to the movement directions X1 and X2, unlike the example shown in Figure 19. Therefore, in the first embodiment of the present invention, even if air hits the surfaces 21a and 21b of the housing 21 facing the movement directions X1 and X2, it is possible to avoid the air hitting the surfaces flowing toward the nozzle surface 31a along the surfaces 21a and 21b facing the movement directions X1 and X2 as shown by the dashed arrows in Figure 9, and it is possible to effectively suppress the generation of airflow near the nozzle surface 31a.

[0047] The shapes of the surfaces 21a and 21b facing the movement directions X1 and X2 may be arc-shaped protruding toward the movement directions X1 and X2 as shown in Figure 8, or they may be other protruding curved surfaces such as ellipses.

[0048] Next, other embodiments of the present invention will be described. In the following description, we will mainly describe parts that differ from the first embodiment of the present invention, and descriptions of the same parts will be omitted as appropriate.

[0049] <Second Embodiment of the Present Invention> Figure 10 shows the configuration of a liquid discharge head 20 according to a second embodiment of the present invention. In Figure 10, (a) is an external perspective view of the liquid discharge head 20, (b) is a plan view of the liquid discharge head 20 as seen from the cover member 22 side, (c) is a front view of the liquid discharge head 20 as seen from the direction of movement, and (d) is a side view of the liquid discharge head 20 as seen from the width direction.

[0050] As shown in Figure 10, in the second embodiment of the present invention, in addition to the surfaces 21a and 21b of the housing 21 facing the movement directions X1 and X2, the surfaces 22a and 22b of the cover member 22 facing the movement directions X1 and X2 are also configured to be curved surfaces that protrude in the movement directions X1 and X2. That is, the surfaces 21a, 21b, 22a, and 22b of the housing 21 and the cover member 22 facing the movement directions X1 and X2 are all curved inclined with respect to the movement directions X1 and X2, and are configured to protrude in the movement directions X1 and X2 towards the center rather than at both ends in the width direction W.

[0051] In this case, when the liquid discharge head 20 moves in one direction X1 in the main scanning direction, as shown by the dashed arrow in Figure 10(a), the air is smoothly guided to both ends in the width direction W by both surfaces 21a and 22a of the housing 21 facing the direction of movement X1 and the cover member 22 facing the direction of movement X1. If the liquid discharge head 20 moves in the opposite direction X2, the air is similarly smoothly guided to both ends in the width direction W by the surface 21b of the housing 21 and the surface 22b of the cover member 22 facing the direction of movement X2 at that time.

[0052] Thus, in the second embodiment of the present invention, since air is smoothly guided by the surfaces 21a and 22a of both the housing 21 and the cover member 22 that face the movement directions X1 and X2, air resistance can be further reduced, and the generation of airflow near the nozzle surface 31a can be more effectively suppressed. As a result, the deviation of the liquid's impact position due to the influence of airflow can be more reliably suppressed.

[0053] <Third Embodiment of the Invention> Figure 11 shows the configuration of a liquid discharge head 20 according to a third embodiment of the present invention. Figures (a), (b), (c), and (d) in Figure 11 show an external perspective view, plan view, front view, and side view of the liquid discharge head 20, similar to (a), (b), (c), and (d) in Figure 10.

[0054] As shown in Figure 11, in the third embodiment of the present invention, the surfaces 21a and 21b of the housing 21 facing the movement directions X1 and X2, and the surfaces 22a and 22b of the cover member 22 facing the movement directions X1 and X2, are not curved surfaces, but are composed of two planes that are inclined to approach each other toward the movement directions X1 and X2. That is, the surfaces 21a and 21b of the housing 21 facing the movement directions X1 and X2, and the surfaces 22a and 22b of the cover member 22 facing the movement directions X1 and X2, are both inclined linearly with respect to the movement directions X1 and X2, and are composed of triangular surfaces that protrude toward the movement directions X1 and X2 towards the center side of the width direction W rather than towards both ends.

[0055] Thus, in the third embodiment of the present invention, the surfaces 21a, 21b, 22a, and 22b of the housing 21 and the cover member 22 facing the respective movement directions X1 and X2 are not curved surfaces, but are composed of two planes (triangular surfaces) inclined with respect to the movement directions X1 and X2. In this case as well, the surfaces 21a, 21b, 22a, and 22b facing the respective movement directions X1 and X2 can smoothly guide the air to both ends of the width direction W (see dashed arrows in Figure 11(a)). For this reason, in the third embodiment of the present invention as well, the generation of airflow near the nozzle surface 31a can be effectively suppressed, and the displacement of the liquid's impact position due to the influence of airflow can be suppressed more reliably.

[0056] <Fourth Embodiment of the Invention> Figure 12 shows the configuration of the liquid discharge head 20 according to the fourth embodiment of the present invention. Figures (a), (b), (c), and (d) in Figure 12 also show the external perspective view, plan view, front view, and side view of the liquid discharge head 20, similar to (a), (b), (c), and (d) in Figure 10 or Figure 11.

[0057] As shown in Figure 12, in the fourth embodiment of the present invention, the surfaces 21a and 21b of the housing 21 facing the movement directions X1 and X2 are inclined to face upwards in the figure. That is, as shown in Figure 12(d), when the housing 21 is viewed from the width direction W, the surfaces 21a and 21b of the housing 21 facing the movement directions X1 and X2 are configured to protrude linearly in the movement directions X1 and X2 as they approach the nozzle surface 31a (towards the bottom of the figure).

[0058] Thus, in the fourth embodiment of the present invention, the surfaces 21a and 21b of the housing 21 facing the movement directions X1 and X2 are configured to protrude in the movement directions X1 and X2 as they approach the nozzle surface 31a. When air strikes these surfaces 21a and 21b, the struck air is guided away from the nozzle surface 31a (upwards in the figure), as shown by the dashed arrow in Figure 12(d). This more effectively suppresses the flow of air toward the nozzle surface 31a, thereby more effectively suppressing the generation of airflow near the nozzle surface 31a. Consequently, deviations in the liquid's impact position can be more reliably suppressed.

[0059] <Fifth Embodiment of the Invention> Furthermore, as shown in the fifth embodiment of the present invention in Figure 13, the surfaces 21a and 21b of the housing 21 facing the movement directions X1 and X2 may protrude in a curved shape (concave curve) rather than a straight line as they approach the nozzle surface 31a (see Figure 13(d)). In this case as well, the air that strikes the surfaces 21a and 21b of the housing 21 facing the movement directions X1 and X2 is guided away from the nozzle surface 31a (upwards in the figure), as shown by the dashed arrows in Figure 13(d). This makes it possible to more effectively suppress the generation of airflow near the nozzle surface 31a and more reliably suppress deviations in the liquid's impact position.

[0060] <Sixth Embodiment of the Invention> Figure 14 is an external perspective view of the liquid discharge head 20 according to the sixth embodiment of the present invention.

[0061] In the sixth embodiment of the present invention shown in Figure 14, multiple grooves 41 extending in the width direction W are provided at intervals from each other in the direction Z perpendicular to the nozzle surface 31a on the surfaces 21a and 21b of the housing 21 facing the movement directions X1 and X2. In Figure 14, the grooves 41 are shown on only one of the two surfaces 21a and 21b of the housing 21 facing the movement directions X1 and X2, but the grooves 41 are also provided on the opposite surface 21b in the same way.

[0062] Thus, because there are multiple grooves 41 on the surfaces 21a and 21b of the housing 21 facing the movement directions X1 and X2, when air strikes the surfaces 21a and 21b of the housing 21 facing the movement directions X1 and X2, the struck air moves along the grooves 41 to both ends in the width direction W, making it possible to guide the air more smoothly. For this reason, according to the configuration of the sixth embodiment of the present invention, the generation of airflow near the nozzle surface 31a can be suppressed more effectively, and the deviation of the liquid's impact position can be suppressed more reliably.

[0063] <Seventh Embodiment of the Invention> Figure 15 is an external perspective view of the liquid discharge head 20 according to the seventh embodiment of the present invention.

[0064] In the seventh embodiment of the present invention shown in Figure 15, a plurality of recesses 42 are provided on the surfaces 21a and 21b of the housing 21 facing the movement directions X1 and X2. The plurality of recesses 42 are arranged in a matrix with spacing between them in two directions: the width direction W and the direction Z perpendicular to the nozzle surface 31a. In Figure 15, only the recesses 42 provided on one side surface 21a of the surfaces 21a and 21b of the housing 21 facing the movement directions X1 and X2 are shown, but the same recesses 42 are also provided on the opposite side surface 21b.

[0065] Thus, because there are multiple recesses 42 on the surfaces 21a and 21b of the housing 21 facing the directions of movement X1 and X2, when air strikes the surfaces 21a and 21b of the housing 21 facing the directions of movement X1 and X2, the striking air is rectified by the multiple recesses 42, suppressing the movement of air toward the nozzle surface 31a. For this reason, according to the configuration of the seventh embodiment of the present invention, the generation of airflow near the nozzle surface 31a can be suppressed more effectively, and the deviation of the liquid's impact position can be suppressed more reliably.

[0066] As described above, the configuration of the liquid ejection head 20 according to each embodiment of the present invention makes it possible to suppress deviations in the point of impact when the liquid ejection head 20 moves, thereby improving the accuracy of ink impact and enabling the provision of high-quality images. Furthermore, since deviations in the point of impact can be suppressed simply by changing the shape of the housing 21, it is possible to improve the accuracy of the point of impact without major design changes.

[0067] Furthermore, as in the embodiments of the present invention described above, when the liquid discharge head 20 moves with the widest surface (the widest surface in the width direction W) of the housing 21 and cover member 22 facing the movement directions X1 and X2, air resistance increases, and airflow associated with the movement of the liquid discharge head 20 tends to be generated. However, by applying the present invention, air resistance can be reduced and the generation of airflow can be suppressed, thus providing a significant benefit. It should be noted that the present invention is not limited to cases where the widest surface of the housing 21 and cover member 22 moves with the movement directions X1 and X2, but is also applicable to liquid discharge heads that move with the narrowest surface facing the movement directions X1 and X2. In that case, by configuring the narrowest surface as a protruding curved surface or triangular in shape, the generation of airflow that affects the liquid's impact position can be suppressed, thereby improving impact accuracy.

[0068] Furthermore, the present invention is not limited to the above embodiments, and at least two configurations from the above embodiments may be appropriately selected and combined. For example, in the configuration of the first embodiment of the present invention shown in Figure 7, a triangular surface configuration as shown in Figure 11, a configuration that guides the airflow away from the nozzle surface 31a as shown in Figures 12 and 13, a configuration having a plurality of grooves 41 as shown in Figure 14, or a configuration having a plurality of recesses 42 as shown in Figure 15 may also be applied.

[0069] Furthermore, the surfaces 21a and 21b of the housing 21 facing the movement directions X1 and X2, and the surfaces 22a and 22b of the cover member 22 facing the movement directions X1 and X2, may be composed of surfaces including both curved surfaces and flat surfaces (inclined surfaces), as long as they are generally curved or triangular in shape, and are not limited to being composed only of curved surfaces or only of flat surfaces (inclined surfaces), or may be composed of only a portion of a curved surface or a flat surface (inclined surface).

[0070] Furthermore, although the above embodiments have described the case in which the liquid discharge head discharges liquid in both the forward and return directions, the present invention is also applicable to a discharge head that discharges liquid in either the forward or return direction.

[0071] In that case, since the problem of misalignment of the liquid's impact position does not occur in the movement path where no liquid is discharged, as shown in Figure 16, only the surfaces 21a, 21b, 22a, and 22b of the housing 21 and cover member 22 that face the movement direction X1 and X2, respectively, may be made into a protruding curved surface that extends toward that movement direction X1.

[0072] Furthermore, the liquid discharge head and head unit according to the present invention can be applied not only to the image forming apparatus described above, but also to other liquid discharge apparatuses.

[0073] For example, the liquid dispensing head and head unit according to the present invention can also be applied to an electrode manufacturing apparatus that dispenses a liquid composition to manufacture electrodes. An example of an electrode manufacturing apparatus to which the present invention can be applied will be described below.

[0074] <Configuration of electrode manufacturing equipment> Figure 17 is a schematic diagram showing the overall configuration of an electrode manufacturing apparatus 700 to which the present invention can be applied.

[0075] Here, as an example of an electrode manufacturing apparatus 700, a manufacturing apparatus for forming an electrode composite layer containing an active material on an electrode substrate (current collector) will be described. The electrode composite layer is used, for example, as part of the configuration of an electrochemical element. There are no particular restrictions on the components of the electrochemical element other than the electrode composite layer, and known components can be appropriately selected. For example, components other than the electrode composite layer include a positive electrode, a negative electrode, and a separator.

[0076] The electrode manufacturing apparatus 700 shown in Figure 17 includes an ejection process section 110 which includes a step of applying a liquid composition for manufacturing electrodes onto a printing substrate 704 having an object to be ejected to form a liquid composition layer, and a heating process section 130 which includes a heating step of heating the liquid composition layer to obtain an electrode composite layer.

[0077] Furthermore, the electrode manufacturing apparatus 700 includes a transport unit 705 for transporting the printing substrate 704. The transport unit 705 transports the printing substrate 704 at a preset speed in the order of the discharge process unit 110 and the heating process unit 130. There are no particular restrictions on the method for manufacturing the printing substrate 704 having an object to be discharged, such as an active material layer, and known methods can be appropriately selected. The discharge process unit 110 includes a liquid discharge head 281a that realizes a dispensing process for applying a liquid composition onto the printing substrate 704, a container 281b that contains the liquid composition 707, and a supply tube 281c that supplies the liquid composition 707 contained in the container 281b to the liquid discharge head 281a.

[0078] In the discharge process section 110, the liquid composition 707 is discharged from the liquid discharge head 281a and applied to the printing substrate 704, forming a thin film layer of the liquid composition. The containment container 281b may be integrated with the electrode manufacturing apparatus or may be detachable from the electrode manufacturing apparatus. Alternatively, the containment container 281b may be a container used for adding to a containment container integrated with the electrode manufacturing apparatus or a containment container detachable from the electrode manufacturing apparatus.

[0079] The containment container 281b and the supply tube 281c can be arbitrarily selected as long as they are capable of stably containing and supplying the liquid composition 707.

[0080] In the heating section 130, a solvent removal step is performed in which the solvent remaining in the liquid composition layer is heated and removed. Specifically, the solvent remaining in the liquid composition layer is heated and dried by the heating device 703 of the heating section 130, thereby removing the solvent from the liquid composition layer. This forms the electrode composite layer. Furthermore, the solvent removal step in the heating section 130 may be performed under reduced pressure.

[0081] There are no particular restrictions on the heating device 703, and it can be appropriately selected according to the purpose. For example, the heating device 703 can be a substrate heater, an IR heater, or a hot air heater. Alternatively, the heating device 703 may be a combination of at least two of the substrate heater, IR heater, and hot air heater. Furthermore, the heating temperature and heating time can be appropriately selected according to the boiling point of the solvent contained in the liquid composition 707 or the film thickness to be formed.

[0082] The object onto which the liquid composition is discharged (hereinafter sometimes referred to as the "discharge target") is not particularly limited as long as it is an object on which a layer containing electrode material is formed, and can be appropriately selected according to the purpose. For example, the target object may be an electrode substrate (current collector), an active material layer, or a layer containing solid electrode material. The target object may also be an electrode composite layer containing active material on an electrode substrate (current collector). Furthermore, the discharge means and discharge process may be means and processes for forming a layer containing electrode material by directly discharging the liquid composition, as long as it is possible to form a layer containing electrode material on the discharge target. Alternatively, the discharge means and discharge process may be means and processes for forming a layer containing electrode material by indirectly discharging the liquid composition.

[0083] By applying the present invention to the electrode manufacturing apparatus 700 described above, deviations in the impact position of the liquid (liquid composition) can be effectively suppressed, and impact accuracy can be improved. As a result, the liquid composition can be discharged to the target location of the object to be discharged.

[0084] Furthermore, the present invention is broadly applicable not only to liquid dispensing devices that dispense liquid onto moving objects such as sheets or electrode substrates that move relative to a liquid dispensing head, but also to liquid dispensing devices that dispense liquid onto objects (moving objects) to which liquid can at least temporarily adhere. Examples of objects (moving objects) to which liquid is dispensed include paper, resin films, wallpaper, and electronic circuit boards. Examples of materials for objects (moving objects) to which liquid is dispensed include paper, leather, metal, plastic, glass, wood, and ceramics.

[0085] Furthermore, the liquid discharged by the liquid dispensing device according to the present invention is not particularly limited, but may include solutions, suspensions, emulsions, etc., containing water, solvents such as organic solvents, colorants such as dyes and pigments, functional materials such as polymerizable compounds, resins, and surfactants, biocompatible materials such as DNA, amino acids and proteins, and calcium, and edible materials such as natural pigments. These are used, for example, in inkjet inks, surface treatment liquids, components of electronic elements and light-emitting elements, liquids for forming electronic circuit resist patterns, and material liquids for 3D molding.

[0086] To summarize the embodiments of the present invention described above, the present invention includes at least the following embodiments.

[0087] [First aspect] The first embodiment is a liquid dispensing head that dispenses liquid while moving, comprising a nozzle for dispensing liquid and a housing having a liquid channel for supplying liquid to the nozzle, wherein, if the width direction is defined as the direction perpendicular to the direction of movement of the liquid dispensing head along the nozzle surface from which the nozzle opens, the surface of the housing facing the direction of movement is inclined with respect to the direction of movement and is configured to protrude in the direction of movement more towards the center than at both ends in the width direction.

[0088] [Second aspect] In a second embodiment, in the first embodiment, the surface of the housing facing the direction of movement is configured with at least a curved surface.

[0089] [Third aspect] A third embodiment is the first embodiment wherein the surface of the housing facing the direction of movement is composed of at least two planes that are inclined to approach each other in the direction of movement.

[0090] [Fourth aspect] A fourth embodiment is a configuration in which, in any one of the first to third embodiments, the surface of the housing facing the direction of movement is configured to protrude linearly in the direction of movement as it approaches the nozzle surface.

[0091] [Fifth aspect] A fifth embodiment is a configuration in which, in any one of the first to third embodiments, the surface of the housing facing the direction of movement is configured to protrude in a curved manner in the direction of movement as it approaches the nozzle surface.

[0092] [Sixth aspect] The sixth embodiment is a cover member that houses a discharge operation control unit that controls a discharge operation for discharging liquid from the nozzle, in any one of the first to fifth embodiments, wherein the surface of the cover member facing the direction of movement is inclined with respect to the direction of movement and is configured to protrude in the direction of movement more towards the center than at both ends in the width direction.

[0093] [Seventh aspect] The seventh embodiment is the sixth embodiment, wherein the surface of the cover member facing the direction of movement is at least a curved surface.

[0094] [Eighth aspect] The eighth aspect is, in the sixth aspect, the surface of the cover member facing the direction of movement is composed of at least two planes that are inclined to approach each other in the direction of movement.

[0095] [Ninth aspect] The ninth embodiment is one of the first to eighth embodiments, wherein the surface of the housing facing the direction of movement has a plurality of grooves extending in the width direction.

[0096] [Tenth aspect] The tenth embodiment is one of the first to ninth embodiments, wherein the surface of the housing facing the direction of movement has a plurality of recesses.

[0097] [The 11th aspect] The eleventh embodiment is a head unit comprising a plurality of liquid dispensing heads according to any one embodiment from the first to the tenth.

[0098] [The 12th aspect] The twelfth embodiment is a liquid dispensing device comprising a liquid dispensing head according to any one of the first to tenth embodiments, or a head unit according to the eleventh embodiment. [Explanation of symbols]

[0099] 13 Head Unit 20 liquid dispensing heads 21 Housing 21a The surface facing the direction of movement 21b The surface facing the direction of movement 22 Cover component 22a The surface facing the direction of movement 22b The surface facing the direction of movement 23. Drive IC (Drive Control Unit) 26 Common channel (liquid channel) 30 nozzles 31a Nozzle surface 41 Groove 42 recess 100 Image forming device (liquid ejection device) W (width direction) X1 Movement direction X2 Movement direction [Prior art documents] [Patent Documents]

[0100] [Patent Document 1] Japanese Patent Publication No. 2004-42580

Claims

1. A nozzle for dispensing liquid, A housing having a liquid channel inside for supplying liquid to the nozzle, Equipped with, In a liquid dispensing head that dispenses liquid while moving, If the width direction is defined as the direction perpendicular to the direction of movement of the liquid discharge head along the nozzle surface through which the nozzle opens, A liquid dispensing head characterized in that the surface of the housing facing the direction of movement is inclined with respect to the direction of movement and is configured to protrude in the direction of movement more towards the center than at both ends in the width direction.

2. The liquid dispensing head according to claim 1, wherein the surface of the housing facing the direction of movement is at least a curved surface.

3. The liquid dispensing head according to claim 1, wherein the surface of the housing facing the direction of movement is composed of at least two planes that are inclined to approach each other in the direction of movement.

4. The liquid dispensing head according to claim 1, wherein the surface of the housing facing the direction of movement is configured to protrude linearly in the direction of movement as it approaches the nozzle surface.

5. The liquid dispensing head according to claim 1, wherein the surface of the housing facing the direction of movement is configured to protrude in a curved manner in the direction of movement as it approaches the nozzle surface.

6. The cover member houses a discharge operation control unit that controls the discharge operation of discharging liquid from the nozzle, The liquid dispensing head according to claim 1, wherein the surface of the cover member facing the direction of movement is inclined with respect to the direction of movement and is configured to protrude in the direction of movement towards the center rather than at both ends in the width direction.

7. The liquid dispensing head according to claim 6, wherein the surface of the cover member facing the direction of movement is at least a curved surface.

8. The liquid dispensing head according to claim 6, wherein the surface of the cover member facing the direction of movement is composed of at least two planes that are inclined to approach each other in the direction of movement.

9. The liquid dispensing head according to claim 1, wherein the surface of the housing facing the direction of movement has a plurality of grooves extending in the width direction.

10. The liquid dispensing head according to claim 1, wherein the surface of the housing facing the direction of movement has a plurality of recesses.

11. A head unit characterized by comprising a plurality of liquid discharge heads as described in claim 1.

12. A liquid dispensing device characterized by comprising the liquid dispensing head described in claim 1.

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