Liquid ejection head and liquid ejection device

Abstract

This liquid ejection head comprises a first flow passage member, a second flow passage member, and an electroconductive part. The first flow passage member is electrically conductive and has a nozzle that ejects a liquid. The second flow passage member supplies the liquid to the first flow passage member. The electroconductive part has a positioning mechanism that determines the position of the nozzle. The electroconductive part is electrically connected to the first flow passage member and has higher electroconductivity than does the second flow passage member.

Description

[Technical Field]

[0001] The disclosed embodiments relate to a liquid ejection head and a liquid ejection device. [Background technology]

[0002] 2. Description of the Related Art Known printing devices include inkjet printers and inkjet plotters that use an inkjet recording method. These inkjet printing devices are equipped with a liquid ejection head that ejects liquid.

[0003] Among such liquid ejection heads, there is known one that is fixed to a conductive frame and grounded. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2006-102984 Summary of the Invention

[0005] A liquid ejection head according to one aspect of the embodiment includes a first flow path member, a second flow path member, and a conductive portion. The first flow path member is conductive and has a nozzle that ejects liquid. The second flow path member supplies the liquid to the first flow path member. The conductive portion has a positioning mechanism that determines the position of the nozzle. The conductive portion is electrically connected to the first flow path member and has higher conductivity than the second flow path member. [Brief explanation of the drawings]

[0006] [Figure 1] FIG. 1 is a front view that schematically shows the front of a printer according to an embodiment. [Figure 2] FIG. 2 is a plan view that schematically shows a general plane of the printer according to the embodiment. [Figure 3] FIG. 3 is a perspective view illustrating an example of a liquid ejection head according to an embodiment. [Figure 4A] FIG. 4A is an enlarged perspective view of region IV shown in FIG. [Figure 4B] FIG. 4B is a perspective view of region IV shown in FIG. 3 as viewed from another direction. [Figure 5A] FIG. 5A is an enlarged perspective view of an area V shown in FIG. [Figure 5B] FIG. 5B is a perspective view of the region V shown in FIG. 3 as viewed from another direction. [Figure 6] FIG. 6 is a cross-sectional view showing an example of a liquid ejection head according to an embodiment. [Figure 7] FIG. 7 is a perspective view showing an example of a second flow path member included in the liquid ejection head according to the embodiment. [Figure 8] FIG. 8 is a perspective view showing an example of a state in which a ground member is installed on the second flow path member shown in FIG. [Figure 9] FIG. 9 is a cross-sectional view showing an example of a liquid ejection head according to an embodiment. [Figure 10] FIG. 10 is a cross-sectional view showing another example of a liquid ejection head according to an embodiment. [Figure 11] FIG. 11 is a perspective view illustrating an example of a conductive member according to an embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0007] The liquid ejection head described above has room for further improvement in terms of achieving stable ground contact.

[0008] Therefore, it is desired to provide a liquid ejection head and a liquid ejection apparatus that can be grounded stably.

[0009] Hereinafter, embodiments of a liquid ejection head and a liquid ejection device disclosed in the present application will be described with reference to the accompanying drawings. Note that the present disclosure is not limited to the embodiments described below. It should be noted that the drawings are schematic, and the dimensional relationships and ratios of elements may differ from reality. Furthermore, the dimensional relationships and ratios may differ between the drawings.

[0010] Furthermore, in the following embodiments, expressions such as "constant," "orthogonal," "perpendicular," or "parallel" may be used, but these expressions do not necessarily mean "constant," "orthogonal," "perpendicular," or "parallel" in the strict sense. In other words, the above expressions allow for deviations due to, for example, manufacturing precision, installation precision, etc.

[0011] Furthermore, the embodiments can be combined as appropriate within the scope of not causing any contradiction in the processing content. Furthermore, the same components in the following embodiments are denoted by the same reference numerals, and redundant explanations will be omitted.

[0012] [Embodiment] <Printer configuration> First, an overview of a printer, which is an example of a liquid ejection device according to an embodiment, will be described with reference to Figures 1 and 2. Figure 1 is a front view that schematically shows the front surface of the printer according to an embodiment. Figure 2 is a plan view that schematically shows the plane of the printer according to an embodiment. The printer according to an embodiment is, for example, a color inkjet printer.

[0013] 1, the printer 1 includes a paper feed roller 2, a guide roller 3, a coater 4, a head case 5, a plurality of transport rollers 6, a plurality of frames 7, a plurality of liquid ejection heads 8, a transport roller 9, a dryer 10, a transport roller 11, a sensor unit 12, and a recovery roller 13. The transport roller 6 is an example of a transport unit.

[0014] Furthermore, the printer 1 has a control unit 14. The control unit 14 controls each part of the printer 1. For example, the control unit 14 controls the operations of the paper feed roller 2, the guide roller 3, the coater 4, the head case 5, the plurality of conveying rollers 6, the plurality of frames 7, the plurality of liquid ejection heads 8, the conveying roller 9, the dryer 10, the conveying roller 11, the sensor unit 12, and the recovery roller 13.

[0015] Printer 1 records images and characters on print paper P by causing droplets to land on print paper P. Print paper P is an example of a recording medium. Before use, print paper P is wound around paper feed roller 2. Printer 1 transports print paper P from paper feed roller 2 through guide roller 3 and coater 4 into head case 5.

[0016] The coater 4 applies the coating agent evenly to the printing paper P. This allows the surface of the printing paper P to be treated, thereby improving the printing quality of the printer 1.

[0017] The head case 5 houses a plurality of transport rollers 6, a plurality of frames 7, and a plurality of liquid ejection heads 8. Inside the head case 5, a space is formed that is isolated from the outside, except for some parts that are connected to the outside, such as the part where the printing paper P enters and leaves.

[0018] At least one of the control factors such as temperature, humidity, and air pressure of the internal space of the head case 5 is controlled by the control unit 14 as necessary. The transport rollers 6 transport the printing paper P inside the head case 5 to the vicinity of the liquid ejection head 8.

[0019] The frame 7 is a rectangular flat plate, and is positioned above and in close proximity to the print paper P being transported by the transport rollers 6. As shown in FIG. 2, the frame 7 is positioned so that its longitudinal direction is perpendicular to the transport direction of the print paper P. Inside the head case 5, multiple (for example, four) frames 7 are positioned at predetermined intervals along the transport direction of the print paper P.

[0020] A liquid, such as ink, is supplied from a liquid tank (not shown) to the liquid ejection head 8. The liquid ejection head 8 ejects the liquid supplied from the liquid tank.

[0021] The control unit 14 controls the liquid ejection head 8 based on data such as images and characters to eject liquid toward the printing paper P. The distance between the liquid ejection head 8 and the printing paper P is, for example, about 0.5 mm to 20 mm.

[0022] The liquid ejection head 8 is fixed to the frame 7. The liquid ejection head 8 is positioned so that its longitudinal direction is perpendicular to the direction in which the printing paper P is transported.

[0023] That is, the printer 1 according to this embodiment is a so-called line printer in which the liquid ejection head 8 is fixed inside the printer 1. Note that the printer 1 according to this embodiment is not limited to a line printer, and may also be a so-called serial printer.

[0024] A serial printer is a printer that alternates between recording by moving the liquid ejection head 8 back and forth in a direction that intersects the transport direction of the printing paper P, for example, in a direction that is approximately perpendicular to the direction, and transporting the printing paper P.

[0025] As shown in Fig. 2, a plurality of (for example, five) liquid ejection heads 8 are fixed to one frame 7. Fig. 2 shows an example in which three liquid ejection heads 8 are positioned in front and two in the rear in the transport direction of the printing paper P, and the liquid ejection heads 8 are positioned in the transport direction of the printing paper P so that the centers of the respective liquid ejection heads 8 do not overlap.

[0026] A head group 8A is made up of multiple liquid ejection heads 8 positioned on one frame 7. The four head groups 8A are positioned along the transport direction of the printing paper P. Four colors of ink are supplied to the liquid ejection heads 8 belonging to the same head group 8A. This allows the printer 1 to print using four colors of ink using the four head groups 8A.

[0027] The colors of ink ejected from each liquid ejection head 8 are, for example, magenta (M), yellow (Y), cyan (C), and black (K). The control unit 14 controls each liquid ejection head 8 to eject ink of multiple colors onto the printing paper P, thereby printing a color image on the printing paper P.

[0028] In order to treat the surface of the printing paper P, a coating agent may be ejected onto the printing paper P from the liquid ejection head 8.

[0029] Furthermore, the number of liquid ejection heads 8 included in one head group 8A and the number of head groups 8A mounted on the printer 1 can be changed as appropriate depending on the object to be printed and the printing conditions. For example, if printing is to be performed within the range that can be printed with one liquid ejection head 8, the number of liquid ejection heads 8 mounted on the printer 1 may be one.

[0030] The printing paper P that has been printed inside the head case 5 is transported to the outside of the head case 5 by transport rollers 9 and passes through the inside of the dryer 10. The dryer 10 dries the printing paper P that has been printed. The printing paper P that has been dried in the dryer 10 is transported by transport rollers 11 and collected by collection rollers 13.

[0031] In the printer 1, by drying the printing paper P in the dryer 10, it is possible to prevent the printing paper P that is wound up in a pile on the collection roller 13 from sticking together and preventing the undried liquid from rubbing against each other.

[0032] The sensor unit 12 is composed of a position sensor, a speed sensor, a temperature sensor, etc. The control unit 14 can determine the state of each part of the printer 1 based on information from the sensor unit 12 and control each part of the printer 1.

[0033] The printer 1 described so far has been shown to use printing paper P as the printing object (i.e., recording medium), but the printing object in the printer 1 is not limited to printing paper P, and the printing object may also be a roll of cloth or the like.

[0034] Furthermore, the printer 1 may transport the printing paper P on a conveyor belt instead of directly transporting the printing paper P. By using a conveyor belt, the printer 1 can print on sheets of paper, cut pieces of cloth, wood, tiles, and the like.

[0035] The printer 1 may also print wiring patterns for electronic devices by ejecting a liquid containing conductive particles from the liquid ejection head 8. The printer 1 may also produce chemicals by ejecting a predetermined amount of liquid chemicals or liquid containing chemicals from the liquid ejection head 8 toward a reaction vessel or the like.

[0036] The printer 1 may also include a cleaning unit that cleans the liquid ejection head 8. The cleaning unit cleans the liquid ejection head 8 by, for example, wiping or capping.

[0037] The wiping process is a process of removing the liquid adhering to the liquid ejection head 8 by wiping the surface of the portion onto which the liquid is ejected with a flexible wiper, for example.

[0038] The capping process is performed, for example, as follows: First, a cap is placed over the surface of the portion onto which the liquid is to be ejected (this is called capping). This forms a substantially sealed space between the surface of the portion onto which the liquid is to be ejected and the cap. Next, the liquid is repeatedly ejected into this sealed space. This makes it possible to remove liquid with a higher viscosity than the standard state, foreign matter, etc., that has clogged the nozzle 21A (see FIG. 3).

[0039] <Configuration of liquid ejection head> Next, the configuration of the liquid ejection head 8 according to the embodiment will be described with reference to Fig. 3. Fig. 3 is a perspective view showing an example of a liquid ejection head according to the embodiment.

[0040] For ease of understanding, FIG. 3 illustrates a three-dimensional Cartesian coordinate system including a Z-axis with the vertically upward direction as the positive direction. This Cartesian coordinate system may also be shown in other drawings used in the following description. For convenience, in the following description, the direction in which the nozzle 21A (see FIG. 3) is located in the liquid ejection head 8, i.e., the negative Z-axis direction, may be referred to as "down" or "downward," and the positive Z-axis direction may be referred to as "up" or "upward." In addition, in FIGS. 3 to 6, various components may be omitted or simplified.

[0041] As shown in FIG. 3, the liquid ejection head 8 includes a first flow path member 21, a second flow path member 22, a pressure applying section 23, a first flow path 27, a second flow path 28, a head cover 29, a heat sink 30, and conductive sections 41 and 42.

[0042] The first flow path member 21 is located on the bottom side of the liquid ejection head 8, facing the printing paper P (see FIG. 1). The first flow path member 21 has a nozzle 21A. The nozzle 21A opens to the bottom surface of the liquid ejection head 8, and ejects liquid supplied inside the first flow path member 21 to the outside.

[0043] The first flow path member 21 is electrically conductive and may be made of, for example, stainless steel.

[0044] The second flow path member 22 is located above the first flow path member 21. The second flow path member 22 supplies liquid to the first flow path member 21. The second flow path member 22 has a flow path 22A connected to the nozzle 21A. Liquid is supplied from the first flow path 27 to the inside of the flow path 22A.

[0045] Examples of materials that can be used for the second flow path member 22 include modified polyphenylene ether (PPE) resins such as Zylon (trade name), and epoxy resins such as Epocluster (registered trademark). The second flow path member 22 may also contain a carbon material such as carbon black.

[0046] The pressurizing unit 23 applies pressure to the first flow path member 21. The pressurizing unit 23 controls the ejection of liquid from the first flow path member 21 in response to a control signal output from the control unit 14 (see FIG. 1). The pressurizing unit 23 has a piezoelectric element that is displaced when energized, and a pressure chamber whose internal pressure changes in response to the displacement of the piezoelectric element. The pressurizing unit 23 changes the internal pressure of the pressure chamber, thereby changing the pressure applied to the first flow path member 21 and controlling the ejection of liquid from the nozzle 21A.

[0047] The first flow path 27 supplies liquid to the flow path 22A of the second flow path member 22. The second flow path 28 recovers liquid from the flow path 22A of the second flow path member 22. When ink is initially introduced into the liquid ejection head 8, air, preservative solution, etc. present inside the flow path 22A can be removed from the second flow path 28, thereby facilitating the introduction of ink into the liquid ejection head 8. When printing, the second flow path 28 may be closed, or the ink in the flow path 22A may be recovered. The liquid recovered from the second flow path 28 is supplied to the first flow path 27, for example, through a filter (not shown).

[0048] The head cover 29 is plate-shaped and is arranged so as to cover a space located on the opposite side of the first flow path member 21 with the second flow path member 22 interposed therebetween.

[0049] The head cover 29 can be made of, for example, a conductive metal material such as aluminum. Alternatively, the head cover 29 may be made of, for example, a conductive or insulating resin material. This allows the liquid ejection head 8 to appropriately dissipate heat via the head cover 29. Furthermore, the head cover 29 may have a higher thermal conductivity than the second flow path member 22. This makes it difficult for heat to be conducted from the head cover 29 to the second flow path member 22. This can reduce the possibility of changes in the properties of the liquid flowing inside the second flow path member 22, causing problems with ejection performance, for example.

[0050] The head cover 29 may be in contact with the second flow path member 22 or may be spaced apart from the second flow path member 22. Positioning the head cover 29 spaced apart from the second flow path member 22 reduces the likelihood of heat conduction from the head cover 29 to the second flow path member 22 and promotes heat conduction to the heat sinks 31 and 32. This reduces the possibility that the properties of the liquid flowing inside the second flow path member 22 will change and cause problems with the discharge performance, for example.

[0051] The heat sinks 30 are plate-shaped members positioned along the YZ plane. The heat sinks 30 are positioned facing each other in the X-axis direction with the head cover 29 in between. The heat sinks 30 may be positioned only at the end on the positive side of the X-axis or the end on the negative side of the X-axis.

[0052] The heat sink 30 may be made of, for example, the same material as the head cover 29. Alternatively, the heat sink 30 may be made of, for example, a material having a higher thermal conductivity than the head cover 29.

[0053] The conductive portions 41 and 42 are located at the ends in the length direction (Y-axis direction). The conductive portion 41 is located at the end on the negative Y-axis direction side, and the conductive portion 42 is located at the end on the positive Y-axis direction side. The conductive portions 41 and 42 have a positioning mechanism that determines the position of the nozzle 21A. Furthermore, the conductive portions 41 and 42 are made of a conductive material that is more conductive than the second flow path member 22, and are electrically connected to the first flow path member 21. This allows for stable grounding.

[0054] <Conductive part configuration> Next, the configuration of the conductive parts 41, 42 of the liquid ejection head 8 according to this embodiment will be further described with reference to Figures 3 to 6. Figure 4A is an enlarged perspective view of region IV shown in Figure 3. Figure 4B is a perspective view of region IV shown in Figure 3, viewed from a different direction. Figure 5A is an enlarged perspective view of region V shown in Figure 3. Figure 5B is a perspective view of region V shown in Figure 3, viewed from a different direction. Figure 6 is a cross-sectional view showing an example of a liquid ejection head according to this embodiment.

[0055] 3 to 4B, conductive portion 41 serving as the first conductive portion has a plate-shaped member 43 and a grounding member 44. Conductive portion 41 can be made of the same metal material as first flow path member 21. This makes it less likely for galvanic corrosion, also known as bimetallic corrosion, to occur, and improves the durability of liquid ejection head 8.

[0056] The plate-shaped member 43 is located on the Z-axis positive side of the second flow path member 22. The plate-shaped member 43 is fixed to the second flow path member 22 using first fixing members 51 and 52.

[0057] The plate-like member 43 has a protrusion 431 that protrudes in the length direction (negative Y-axis direction), and the plate-like member 43 has a substantially L-shape when viewed in a plan view in the Z-axis direction. When the liquid ejection head 8 is mounted on a liquid ejection device, the plate-like member 43 functions as a positioning mechanism at one end in the length direction (negative Y-axis direction).

[0058] The plate-like member 43 can be fixed to the ground member 44 of the conductive portion 41 using the first fixing members 51 and 52. This results in the plate-like member 43 being fixed to the ground member 44, which has higher rigidity than the second flow path member 22, and the positioning accuracy of the plate-like member 43 is improved.

[0059] The ground member 44 is located on the negative Z-axis direction side of the second flow path member 22. The ground member 44 is fixed to the second flow path member 22 using first fixing members 51 and 52. The ground member 44 is also fixed to the first flow path member 21 and the second flow path member 22 using second fixing members 61 and 62. The first fixing members 51 and 52 and the second fixing members 61 and 62 may be, for example, metal screw members.

[0060] 3, 5A, and 5B, conductive portion 42 serving as the second conductive portion may include plate-shaped member 45 and ground member 46. Plate-shaped member 45 is located on the positive Z-axis direction side of second flow path member 22. Plate-shaped member 45 is fixed to second flow path member 22 using first fixing members 53 and 54.

[0061] Plate-like member 45 protrudes in the lengthwise direction (positive Y-axis direction) and has a notch 451 in the center in the widthwise direction (positive Y-axis direction). When liquid ejection head 8 is mounted on a liquid ejection device, plate-like member 45 functions as a positioning mechanism at one end in the lengthwise direction (positive Y-axis direction). For example, by positioning liquid ejection head 8 so that a columnar or rod-shaped guide member (not shown) extending in the heightwise direction (Z-axis direction) contacts notch 451, a liquid ejection device having nozzle 21A at a predetermined position can be obtained.

[0062] The plate-shaped member 45 can be fixed to the ground member 46 of the conductive portion 42 using the first fixing members 53 and 54. This results in the plate-shaped member 45 being fixed to the ground member 46, which has higher rigidity than the second flow path member 22, and the positioning accuracy of the plate-shaped member 45 is improved.

[0063] The ground member 46 is located on the negative Z-axis direction side of the second flow path member 22. The ground member 46 is fixed to the second flow path member 22 using first fixing members 53 and 54. The ground member 46 is also fixed to the first flow path member 21 and the second flow path member 22 using second fixing members 63 and 64. The first fixing members 53 and 54 and the second fixing members 63 and 64 may be, for example, metal screw members.

[0064] As shown in FIG. 6 , the grounding member 44 may have a first portion 441 and a second portion 442. The grounding member 46 may have a first portion 461 and a second portion 462. The first portions 441 and 461 may be contact surfaces that come into contact with the mounting surfaces 1f and 1g of a printer 1, which is an example of a liquid ejection device, when the liquid ejection head 8 is mounted on the mounting surfaces 1f and 1g. The liquid ejection head 8 mounted on the mounting surfaces 1f and 1g can be stably grounded by properly grounding the first portions 441 and 461. In this way, by having the conductive portions 41 and 42 that are electrically connected to the first flow path member 21 and have higher conductivity than the second flow path member 22, stable grounding is possible, for example, even when electrical noise occurs.

[0065] The second portions 442, 462 are contact surfaces that come into contact with the first flow path member 21. The second fixing members 61-64 that fix the first flow path member 21 and the second flow path member 22 penetrate these second portions 442, 462. The second fixing members 61, 62 penetrate the second portion 442. The second fixing members 63, 64 penetrate the second portion 462. In this way, by having the second fixing members 61-64 penetrate the second portions 442, 462 of the ground members 44, 46, the ground members 44, 46 can be brought into stable contact with the first flow path member 21, and the ground resistance of the liquid ejection head 8 can be reduced.

[0066] Furthermore, since the second fixing members 61, 62 penetrate the second portion 442 of the grounding member 44 and the second fixing members 63, 64 penetrate the second portion 462 of the grounding member 46, deformation of the grounding members 44, 46 and tilting of the grounding members 44, 46 due to the moment force generated by fastening the second fixing members 61-64 are less likely to occur compared to when the second fixing members 61, 62 penetrate a portion other than the second portions 442, 462.

[0067] 3 to 5B, the grounding member 44 of the conductive portion 41 may be in contact with the first flow path member 21 across the width direction (X-axis direction). The grounding member 46 of the conductive portion 42 may be in contact with the first flow path member 21 across the width direction (X-axis direction). This increases the contact area between the conductive portions 41, 42 and the first flow path member 21, allowing the first flow path member 21 to be stably grounded.

[0068] Furthermore, the conductive portions 41, 42 may be in contact with the second flow path member 22 across the width direction (X-axis direction), thereby improving the positional stability of the conductive portions 41, 42 relative to the second flow path member 22.

[0069] As shown in FIG. 6 , the area of ​​the first portion 441 of the grounding member 44 may be larger than the area of ​​the second portion 442. Similarly, the area of ​​the first portion 461 of the grounding member 46 may be larger than the area of ​​the second portion 462. The area of ​​the second portion 442 may be larger than the area of ​​the first portion 441, and the area of ​​the second portion 462 may be larger than the area of ​​the first portion 461. When the area of ​​the second portion 442 is larger than the area of ​​the first portion 441, for example, the contact area between the first flow path member 21 and the grounding member 44 can be increased. When the area of ​​the second portion 462 is larger than the area of ​​the first portion 461, for example, the contact area between the first flow path member 21 and the grounding member 46 can be increased. This allows for stable grounding.

[0070] 6, the grounding member 44 may have a step between the first portion 441 and the second portion 442, or the first portion 441 and the second portion 442 may be flush with each other. Similarly, the grounding member 46 may have a step between the first portion 461 and the second portion 462, or the first portion 461 and the second portion 462 may be flush with each other.

[0071] Fig. 7 is a perspective view showing an example of a second flow path member included in a liquid ejection head according to an embodiment. Fig. 8 is a perspective view showing an example of a state in which a ground member is installed on the second flow path member shown in Fig. 7. Fig. 9 is a cross-sectional view showing an example of a liquid ejection head according to an embodiment.

[0072] 7, the second flow path member 22 may have a bottom surface 221 and a peripheral wall 222. The bottom surface 221 is recessed toward the positive Z-axis direction from the end face of the second flow path member 22 on the negative Z-axis direction side, which is positioned opposite the first flow path member 21. The peripheral wall 222 is positioned to surround the bottom surface 221. The ground member 44 is attached so as to be embedded in a recess of the second flow path member 22, which has the bottom surface 221 and the peripheral wall 222. By embedding the ground member 44 in the recess of the second flow path member 22 in this way, the rigidity of the second flow path member 22 is improved, and the positional stability of the ground member 44 in the liquid ejection head 8 is also improved.

[0073] The second flow path member 22 may also have a protruding pin 223. The protruding pin 223 protrudes from the bottom surface 221 in the negative Z-axis direction. As shown in FIG. 8, the protruding pin 223 is inserted into a through-hole 443 that penetrates the ground member 44 in the thickness direction (Z-axis direction). As shown in FIG. 9, the tip of the protruding pin 223 is located inside the first flow path member 21. By having such a protruding pin 223, the positional stability of the first flow path member 21 and the second flow path member 22 is improved. Furthermore, since the material cost of the ground member 44 can be reduced compared to when a protruding pin protruding from the ground member 44 is provided, the manufacturing cost of the liquid ejection head 8 can be reduced.

[0074] 7 to 9, the shape of the second flow path member 22 located on the ground member 44 side has been described, but the second flow path member 22 located on the ground member 46 side can also be made to have a similar shape.

[0075] Returning to FIG. 6 , the liquid ejection head 8 may have a connection portion 50. The connection portion 50 connects the conductive portions 41, 42 located at both ends in the length direction (Y-axis direction) to each other. The connection portion 50 is conductive. The connection portion 50 can be made of the same metal material as the first flow path member 21. The connection portion 50 may be a part of the first flow path member 21.

[0076] The connection part 50 may be located between the nozzle 21A and the conductive parts 41, 42. The connection part 50 may be, for example, a lid-like member that closes the liquid flow path located inside the first flow path member 21. The connection part 50 may also have, for example, a housing part that houses the pressurizing part 23 (see FIG. 3 ). The connection part 50 may be integral with the first flow path member 21 or may be separate from the first flow path member 21. By having the connection part 50 in the liquid ejection head 8, the first flow path member 21 can be quickly brought into electrical contact with the liquid ejection device, and stable grounding can be achieved.

[0077] Fig. 10 is a cross-sectional view showing another example of a liquid ejection head according to an embodiment. As shown in Fig. 10, the liquid ejection head 8 may have a conductive member 40. The conductive member 40 can be made of the same metal material as the first flow path member 21.

[0078] 10 and 11, the conductive member 40 may have grounding portions 44A and 46A located at both ends in the length direction (Y-axis direction), and a connecting portion 50A located between the grounding portions 44A and 46A.

[0079] The grounding portions 44A and 46A have first portions 441 and 461, respectively, that are placed on the mounting surfaces 1f and 1g of the printer 1. The grounding portions 44A and 46A correspond to the grounding members 44 and 46 shown in FIG. 6. The connecting portion 50A corresponds to the connecting portion 50 shown in FIG. 6. The conductive member 40 integrally includes the grounding portions 44A and 46A and the connecting portion 50A. With a liquid ejection head 8 that includes such a conductive member 40, the grounding portions 44A and 46A are less likely to shift in position, even if the liquid ejection head 8 is subjected to an external force. This allows for stable grounding of the liquid ejection head 8.

[0080] <Other embodiments> In the above-described embodiment, the ground members 44, 46 are fixed at four points using the first fixing member and the second fixing member, but the ground members 44, 46 may be fixed at two or more points. For example, if the ground members 44, 46 are fixed at two points, one point may function to position the ground members 44, 46, and the other point may function to prevent rotation of the ground members 44, 46. This makes it less likely that the ground members 44, 46 will become misaligned, even if the liquid ejection head 8 is subjected to an external force.

[0081] The above-described embodiment describes a mode in which ink is supplied from the outside to a reservoir formed by the second flow path member 22, and a mode in which ink is supplied from the outside to the reservoir and recovered from the reservoir to the outside during printing. In the latter mode, ink may be supplied from the reservoir to the first flow path member 21 and recovered from the first flow path member 21 to the reservoir. Furthermore, ink may be supplied to and recovered from the flow path facing the nozzle 21A within the first flow path member 21, thereby preventing ink from accumulating within and around the nozzle 21A. In such a mode, ink is supplied from the outside to the liquid ejection head 8 as a whole, a portion of the ink is ejected, and the ink that was not ejected is recovered to the outside. The ink recovered to the outside may be supplied again to the liquid ejection head 8. That is, the ink may be circulated. The supply and recovery of ink to the liquid ejection head 8, or the circulation of ink, may be controlled by the control unit 14.

[0082] As described above, the liquid ejection head 8 according to this embodiment includes the first flow path member 21, the second flow path member 22, and the conductive portions 41 and 42. The first flow path member 21 is conductive and has the nozzle 21A that ejects liquid. The second flow path member 22 supplies liquid to the first flow path member 21. The conductive portions 41 and 42 have a positioning mechanism that determines the position of the nozzle 21A. The conductive portions 41 and 42 are electrically connected to the first flow path member 21 and have higher conductivity than the second flow path member 22. As a result, the liquid ejection head 8 according to this embodiment can achieve stable grounding.

[0083] Further advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details and representative embodiments shown and described above. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents. [Explanation of symbols]

[0084] 1. Printer 8 Liquid ejection head 14 Control Unit 21 first flow path member 21A Nozzle 22 second flow path member 23 Pressure unit 29 Headcover 30 Heat sink 40 Conductive material 41, 42 Conductive part 43,45 Plate-shaped members 44,46 Grounding member

Claims

1. a conductive first flow path member having a nozzle for discharging a liquid; a second flow path member that supplies the liquid to the first flow path member; a positioning mechanism for determining the position of the nozzle, the positioning mechanism being electrically connected to the first flow path member and having a higher conductivity than the second flow path member; Equipped with a fixing member that fixes the first flow path member and the second flow path member, The liquid ejection head, wherein the fixing member penetrates the conductive portion.

2. a conductive first flow path member having a nozzle for discharging a liquid; a second flow path member that supplies the liquid to the first flow path member; a positioning mechanism for determining the position of the nozzle, the positioning mechanism being electrically connected to the first flow path member and having a higher conductivity than the second flow path member; Equipped with a fixing member that fixes the first flow path member and the second flow path member, The liquid ejection head, wherein the immobilizing member penetrates the contact surface between the conductive portion and the first flow path member.

3. a conductive first flow path member having a nozzle for discharging a liquid; a second flow path member that supplies the liquid to the first flow path member; a positioning mechanism for determining the position of the nozzle, the positioning mechanism being electrically connected to the first flow path member and having a higher conductivity than the second flow path member; Equipped with the positioning mechanism has a plate-like member, The liquid ejection head, wherein the plate-like member is fixed to the conductive portion using a fixing member.

4. a conductive first flow path member having a nozzle for discharging a liquid; a second flow path member that supplies the liquid to the first flow path member; a positioning mechanism for determining the position of the nozzle, the positioning mechanism being electrically connected to the first flow path member and having a higher conductivity than the second flow path member; Equipped with the second flow path member has a recess, The conductive portion is embedded in the recess.

5. 5. The liquid ejection head according to claim 1, wherein the conductive portion and the first flow path member are in contact with each other across the width direction.

6. 5. The liquid ejection head according to claim 1, wherein the conductive portion and the second flow path member are in contact with each other across the width direction.

7. 5. The liquid ejection head according to claim 1, wherein the conductive portion is made of the same metal material as the first flow path member.

8. 5. The liquid ejection head according to claim 1, wherein the conductive portion is fixed at two or more points.

9. the conductive portion has a first conductive portion and a second conductive portion located at both ends in a length direction, 5. The liquid ejection head according to claim 1, further comprising a connection portion that connects the first conductive portion and the second conductive portion.

10. A liquid ejection head according to any one of claims 1 to 4, a mounting surface on which the liquid ejection head is mounted; and The conductive portion of the liquid ejection head is located on the mounting surface.

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