Droplet discharge head and droplet discharge device

Abstract

To provide a droplet discharge head and a droplet discharge device which can improve printing quality.SOLUTION: A droplet discharge head includes a flow channel member, a reservoir, a heater, and a metal member. The flow channel member has a plurality of discharge holes for discharging a droplet. The reservoir is positioned on the flow channel member, and supplies a liquid to the flow channel member. The heater is positioned between the flow channel member and the reservoir, and raises the temperature of the liquid supplied to the flow channel member. The metal member is positioned so as to be brought into contact at least a part of a flow channel extending along the surface on the side of the flow channel member, in the reservoir. The heater and the metal member are thermally connected to each other in a direct or indirect manner.SELECTED DRAWING: Figure 6

Description

[Technical field]

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

[0002] Conventionally, as a printing head, for example, a droplet ejection head that performs various printing by ejecting droplets onto a recording medium is known. Patent Document 1 discloses a printing device equipped with a plurality of heaters that heat the print head and a heater driver that independently drives the plurality of heaters. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 6-115074 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the above-mentioned conventional technology, when the ejection of droplets is temporarily stopped, even if the heater is stopped at the same time, the flow of liquid around the heater stops, and there are cases in which excess heat from the heater causes the temperature of the droplet ejection head to rise above a specified temperature.

[0005] Furthermore, if droplet ejection is resumed before this phenomenon subsides, liquid at a temperature higher than the specified temperature will be ejected as droplets, which could cause the concentration of the liquid to change from the specified state, resulting in a significant reduction in print quality.

[0006] One aspect of the embodiment has been made in view of the above, and aims to provide a droplet ejection head and a droplet ejection device that can improve print quality. [Means for solving the problem]

[0007] The droplet ejection head of the present disclosure includes a flow path member, a reservoir, a heater, and a metal member. The flow path member has a plurality of ejection holes through which droplets are ejected. The reservoir is located on the flow path member and supplies liquid to the flow path member. The heater is located between the flow path member and the reservoir and heats the liquid supplied to the flow path member. The metal member is located in the reservoir so as to contact at least a portion of a flow path extending along a surface on the flow path member side. The heater and the metal member are thermally connected directly or indirectly. Effect of the Invention

[0008] According to one aspect of the embodiment, it is possible to provide a droplet ejection head and a droplet ejection device that can improve print quality. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a schematic side view of a printer according to an embodiment. [Diagram 2] FIG. 2 is a schematic plan view of the printer according to the embodiment. [Diagram 3] FIG. 3 is an exploded perspective view showing a schematic configuration of a droplet ejection head according to an embodiment. [Figure 4] FIG. 4 is a perspective view showing an example of the configuration of a branch flow path member according to the embodiment. [Diagram 5] FIG. 5 is a cross-sectional view showing an example of an internal configuration of a reservoir according to the embodiment. [Figure 6] FIG. 6 is a cross-sectional view showing an example of the configuration of a branch flow path member, a reservoir, and their surroundings according to the embodiment. [Figure 7] FIG. 7 is an enlarged perspective view showing an example of the configuration of a fixing portion according to the embodiment. [Figure 8] FIG. 8 is an enlarged cross-sectional view showing an example of the configuration of the reservoir and the metal member according to the embodiment. [Figure 9] FIG. 9 is a cross-sectional view showing an example of the configuration of a branch flow path member, a reservoir and their surroundings according to Alternative Embodiment 1. As shown in FIG. [Figure 10] FIG. 10 is a cross-sectional view showing an example of the configuration of a branch flow path member, a reservoir and their surroundings according to another embodiment 2. In FIG. [Figure 11] FIG. 11 is a cross-sectional view showing an example of the configuration of a branch flow path member, a reservoir and their surroundings according to another embodiment 3. In FIG. [Figure 12] FIG. 12 is a cross-sectional view showing an example of the configuration of a branch flow path member, a reservoir and their surroundings according to another embodiment 4. As shown in FIG. [Figure 13] FIG. 13 is a cross-sectional view showing an example of the configuration of a branch flow path member, a reservoir and their surroundings according to another embodiment 5. As shown in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, a detailed description will be given of a form for carrying out a droplet ejection head and a droplet ejection device according to the present disclosure (hereinafter, referred to as an "embodiment") with reference to the drawings. Note that the present disclosure is not limited to the embodiment. In addition, each embodiment can be appropriately combined as long as the processing contents are not contradictory. In addition, the same parts in each of the following embodiments are given the same reference numerals, and duplicated explanations will be omitted.

[0011] In addition, in the embodiments described below, expressions such as "uniform", "orthogonal", and "parallel" may be used, but these expressions do not necessarily mean "uniform", "orthogonal", and "parallel" strictly. In other words, each of the above expressions allows for deviations due to, for example, manufacturing precision, installation precision, and the like.

[0012] In addition, in order to make the explanation easier to understand, each of the drawings referred to below may show an orthogonal coordinate system that defines an X-axis direction, a Y-axis direction, and a Z-axis direction that are perpendicular to each other, and has the positive Z-axis direction as the vertically upward direction.

[0013] <Printer configuration> First, an overview of a printer 1, which is an example of a droplet ejection device according to an embodiment, will be described with reference to Fig. 1 and Fig. 2. Fig. 1 is a schematic side view of the printer 1 according to an embodiment, and Fig. 2 is a schematic plan view of the printer 1 according to an embodiment. The printer 1 according to an embodiment is, for example, a color inkjet printer.

[0014] As shown in FIG. 1, the printer 1 includes a paper feed roller 2, a guide roller 3, an applicator 4, a head case 5, a plurality of conveying rollers 6, a plurality of frames 7, a plurality of droplet ejection heads 8, a conveying roller 9, a dryer 10, a conveying roller 11, a sensor unit 12, and a recovery roller 13.

[0015] Furthermore, the printer 1 has a control unit 14 that controls the paper feed roller 2, guide roller 3, coater 4, head case 5, multiple conveying rollers 6, multiple frames 7, multiple droplet ejection heads 8, conveying roller 9, dryer 10, conveying roller 11, sensor unit 12 and recovery roller 13.

[0016] The printer 1 records images and characters on the printing paper P by causing droplets to land on the printing paper P. The printing paper P is an example of a recording medium. Before use, the printing paper P is wound around a paper feed roller 2. The printer 1 transports the printing paper P from the paper feed roller 2 through a guide roller 3 and a coater 4 into the inside of a head case 5.

[0017] The coater 4 applies the coating agent evenly to the printing paper P. This allows the printing paper P to be surface-treated, thereby improving the printing quality of the printer 1.

[0018] The head case 5 houses a plurality of transport rollers 6, a plurality of frames 7, and a plurality of droplet ejection heads 8. Inside the head case 5, a space is formed that is isolated from the outside, except for a portion that is connected to the outside, such as a portion where the printing paper P enters and exits.

[0019] At least one of 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 droplet ejection heads 8.

[0020] The frame 7 is a rectangular flat plate, and is positioned adjacent to and above the print paper P 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 along the transport direction of the print paper P.

[0021] In the following description, the transport direction of the printing paper P is also referred to as the "sub-scanning direction," and the direction perpendicular to the sub-scanning direction and parallel to the printing paper P is also referred to as the "main scanning direction."

[0022] A liquid, such as ink, is supplied from a liquid tank (not shown) to the droplet ejection head 8. In other words, ink is one example of a liquid. The droplet ejection head 8 ejects the liquid supplied from the liquid tank as droplets.

[0023] The control unit 14 controls the droplet ejection head 8 based on data such as images and characters, and ejects droplets toward the printing paper P. The distance between the droplet ejection head 8 and the printing paper P is, for example, about 0.5 to 20 mm.

[0024] The droplet ejection head 8 is fixed to the frame 7. The droplet ejection head 8 is fixed to the frame 7, for example, at both ends in the longitudinal direction. The droplet ejection head 8 is positioned so that the longitudinal direction is perpendicular to the transport direction of the printing paper P.

[0025] That is, the printer 1 according to the embodiment is a so-called line printer in which the droplet ejection head 8 is fixed inside the printer 1. Note that the printer 1 according to the embodiment is not limited to a line printer, and may be a so-called serial printer.

[0026] A serial printer is a printer that alternates between recording by moving a droplet ejection head 8 back and forth in a direction intersecting the transport direction of the printing paper P, for example, in a direction that is approximately perpendicular, and transporting the printing paper P.

[0027] As shown in Fig. 2, multiple (for example, five) droplet ejection heads 8 are fixed to one frame 7. Fig. 2 shows an example in which three droplet ejection heads 8 are positioned in the front and two in the rear in the transport direction of the print paper P, and the droplet ejection heads 8 are positioned in the transport direction of the print paper P such that the centers of the droplet ejection heads 8 do not overlap.

[0028] A head group 8A is made up of a plurality of droplet ejection heads 8 positioned on one frame 7. The four head groups 8A are positioned along the transport direction of the print paper P. Ink of the same color is supplied to droplet ejection heads 8 belonging to the same head group 8A. This allows the printer 1 to print with four colors of ink using the four head groups 8A.

[0029] The colors of ink ejected from each head group 8A are, for example, magenta (M), yellow (Y), cyan (C), and black (K). The control unit 14 controls each head group 8A to eject ink of multiple colors onto the printing paper P, thereby printing a color image on the printing paper P.

[0030] In order to treat the surface of the printing paper P, a coating agent may be ejected onto the printing paper P from the droplet ejection head 8.

[0031] Furthermore, the number of droplet 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 the color printed on the printing paper P is a single color and printing is performed in an area that can be printed with one droplet ejection head 8, the number of droplet ejection heads 8 mounted on the printer 1 may be one.

[0032] The print 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 print paper P that has been printed. The print paper P that has been dried in the dryer 10 is transported by transport rollers 11 and collected by collection rollers 13.

[0033] In the printer 1, by drying the printing paper P with the dryer 10, it is possible to reduce adhesion between overlapping printing papers P that are wound up on the recovery roller 13 and rubbing of undried liquid.

[0034] 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.

[0035] In the printer 1 described so far, the printing object (i.e., the recording medium) is a printing paper P, but the printing object in the printer 1 is not limited to the printing paper P. For example, the printing object may be a roll of cloth.

[0036] Furthermore, the printer 1 may convey the print paper P on a conveyor belt instead of directly conveying the print 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.

[0037] The printer 1 may also print wiring patterns for electronic devices by discharging droplets containing conductive particles from the droplet discharging head 8. The printer 1 may also prepare chemicals by discharging a predetermined amount of liquid chemicals or droplets containing chemicals from the droplet discharging head 8 toward a reaction vessel or the like.

[0038] The printer 1 may also include a cleaning unit that cleans the droplet ejection head 8. The cleaning unit cleans the droplet ejection head 8 by, for example, wiping or capping.

[0039] The wiping process is a process of removing liquid adhering to the droplet ejection head 8 by wiping the surface of the area from which droplets are ejected with a flexible wiper, for example.

[0040] The capping process is carried out, for example, as follows: First, a cap is placed over the surface of the portion from which the droplets are discharged (this is called capping). This forms a nearly sealed space between the surface of the portion from which the droplets are discharged and the cap.

[0041] Next, droplets are repeatedly ejected from the sealed space, which makes it possible to remove liquids with higher viscosity than normal and foreign matter that have become clogged in the ejection holes (nozzles) that eject the droplets.

[0042] <Configuration of droplet ejection head> Next, the configuration of the droplet ejection head 8 according to the embodiment will be described with reference to Figures 3 to 5. Figure 3 is an exploded perspective view showing a schematic configuration of the droplet ejection head 8 according to the embodiment.

[0043] 3, the droplet ejection head 8 includes a head body 20, a wiring section 30, a head cover 40, and two heat sinks 45. The head body 20 includes a flow path member 21, a piezoelectric actuator substrate 22 (see FIG. 6), a branch flow path member 23, and a reservoir 24.

[0044] In the following description, for convenience, the direction in which the head body 20 is provided in the droplet ejection head 8 may be referred to as "downward," and the direction in which the head cover 40 is provided relative to the head body 20 may be referred to as "upward."

[0045] The flow path member 21 of the head body 20 has a substantially flat plate shape and has a first surface 21a (see FIG. 6) which is one main surface, and a second surface 21b (see FIG. 6) located on the opposite side of the first surface 21a. The first surface 21a has an opening (not shown), and liquid is supplied from a reservoir 24 to the inside of the flow path member 21 through the opening.

[0046] The second surface 21b has a plurality of ejection holes (not shown) that eject droplets onto the print paper P. The flow path member 21 has therein a flow path that allows liquid to flow from the first surface 21a to the second surface 21b.

[0047] The piezoelectric actuator substrate 22 is located on the first surface 21a of the flow path member 21. The piezoelectric actuator substrate 22 has a plurality of displacement elements (not shown). A flexible substrate 31 of the wiring section 30 is electrically connected to the piezoelectric actuator substrate 22.

[0048] The branch flow path member 23 is located on the flow path member 21. The branch flow path member 23 has therein branch flow paths (not shown) that are connected to the flow paths of the flow path member 21. Such branch flow paths are provided near the ends of the branch flow path member 23 in the longitudinal direction.

[0049] The two branch flow paths each branch ink flowing in from an ink outlet port 24b (described later) in the short direction of the branch flow path member 23 and send the ink to the flow path member 21. The flow path member 21 has two openings through which ink flows in at both ends in the longitudinal direction, so the flow path is branched at the branch flow paths, but such branching is not necessarily required.

[0050] The branch flow path may be a connecting flow path that connects the reservoir 24 and the flow path member 21. The branch flow path member 23 may be called a connecting flow path member. In addition, ink may be directly supplied from the reservoir 24 to the flow path member 21. Fig. 4 is a perspective view showing an example of the configuration of the branch flow path member 23 according to the embodiment.

[0051] 4, the branch flow path member 23 is a box-shaped member that extends long in the primary scanning direction (Y-axis direction) and has an open top. The branch flow path member 23 has a bottom portion 23a, a peripheral wall portion 23b that stands up from the bottom portion 23a, and two slit portions 23c.

[0052] The bottom portion 23a is located on the flow path member 21. The peripheral wall portion 23b has a frame shape, is connected to both ends of the bottom portion 23a in the longitudinal direction, and is located so as to surround the periphery of the bottom portion 23a. That is, the branch flow path member 23 has a box shape formed by the bottom portion 23a and the peripheral wall portion 23b.

[0053] Since the branch flow path member 23 has a box shape, it is possible to increase the rigidity of the branch flow path member 23 compared to a case in which a part of the metal member 26 is housed inside the box shape and the branch flow path member 23 has a flat plate shape. As a result, it is possible to reduce the amount of deflection of the nozzle surface of the flow path member 21 joined to the branch flow path member 23.

[0054] The slit portion 23c is a groove-shaped gap extending along the longitudinal direction (Y-axis direction) of the branch flow path member 23. The two slit portions 23c are provided to sandwich the bottom portion 23a in a plan view. A flexible substrate 31 (see FIG. 3) connected to the piezoelectric actuator substrate 22 is inserted into the slit portion 23c.

[0055] The peripheral wall portion 23b of the branch flow path member 23 further has an eaves portion 23d that protrudes outward from the branch flow path member 23. This makes it possible to prevent the droplets discharged from the discharge holes of the flow path member 21 from scattering onto the heat sink 45 (see FIG. 6) or the like.

[0056] Returning to the explanation of FIG. 3, the reservoir 24 is located on the branch flow path member 23. The reservoir 24 is provided with openings 24a at both ends in the main scanning direction (the Y-axis direction in the figure). The reservoir 24 has a flow path therein, and liquid is supplied from the outside via the openings 24a. The reservoir 24 supplies liquid to the flow path member 21. The reservoir 24 also stores the liquid supplied to the flow path member 21.

[0057] 5 is a cross-sectional view showing an example of the internal configuration of the reservoir 24 according to the embodiment. The reservoir 24 is a box-shaped member that extends long in the main scanning direction (Y-axis direction). An opening 24a through which ink is supplied from the outside is located on the upper surface (the surface on the positive Z-axis direction side) of the reservoir 24. A pair of such openings 24a is provided on both ends of the reservoir 24 in the main scanning direction.

[0058] Furthermore, an ink outlet port 24b that leads the ink flowing through the reservoir 24 to the branch flow path member 23 (see FIG. 3) is located on the lower surface (surface on the Z-axis negative direction side) of the reservoir 24. A pair of such ink outlet ports 24b are provided on both ends of the reservoir 24 in the main scanning direction.

[0059] The reservoir 24 has a reservoir base 101, an upper cover 102, and a lower cover 103. The reservoir base 101 is formed with a groove and a through hole that become the flow path of the reservoir 24. That is, the main member that constitutes the flow path of the reservoir 24 is the reservoir base 101. The reservoir base 101 is made of a first member. The first member is made of, for example, a resin. Such a resin has a low thermal conductivity of, for example, about 0.1 to 0.4 w / m·k.

[0060] The top cover 102 is positioned so as to cover the first surface of the reservoir base 101. The first surface of the reservoir base 101 is the surface of the reservoir base 101 that is positioned on the opposite side to the flow path member 21 (i.e., the positive Z-axis direction side). The top cover 102 has, for example, the pair of openings 24a described above, and is made of, for example, resin.

[0061] The lower lid 103 is positioned so as to cover the second surface of the reservoir base 101. The second surface of the reservoir base 101 is the surface located on the flow path member 21 side (i.e., the Z-axis negative direction side) of the reservoir base 101. The lower lid 103 has, for example, the pair of ink outlet ports 24b described above, and is made of, for example, resin.

[0062] A first flow path 104, a second flow path 105, and a connection portion 106 are provided inside the reservoir 24. The first flow path 104 is composed of a groove portion formed on a first surface of the reservoir base 101 and an upper cover 102. The second flow path 105 is composed of a groove portion formed on a second surface of the reservoir base 101 and a lower cover 103. The connection portion 106 connects the first flow path 104 and the second flow path 105. The second flow path 105 is an example of a flow path.

[0063] In the first flow path 104, the ink supplied from the opening 24a flows toward the center of the reservoir base 101 in the longitudinal direction.

[0064] In the first flow path 104, the ink that has reached the center of the reservoir 24 from both ends flows through a connection portion 106 formed in the center of the reservoir base 101, and enters the second flow path 105. The connection portion 106 is provided so as to penetrate between the first flow path 104 and the second flow path 105 in the vertical direction (Z-axis direction).

[0065] In the second flow path 105, the ink supplied from the connection portion 106 flows toward both ends in the longitudinal direction of the reservoir base 101. The ink that reaches the ends is then discharged from the reservoir 24 to the branch flow path member 23 (see FIG. 3) through the ink outlet 24b.

[0066] As described above, the reservoir 24 according to the embodiment has one opening 24a at each of both ends in the longitudinal direction. The reservoir 24 has a structure that allows ink to be supplied into the reservoir 24 from both of the two openings 24a.

[0067] As a result, by initially supplying ink from only one of the openings 24a, it is possible to easily remove any air remaining inside and any liquid that was previously in the ink from the other opening 24a. When actually printing, ink may be supplied from only one opening 24a, or from both openings 24a.

[0068] Also, even during printing, ink may be supplied from one of the openings 24a, and the ink in the reservoir 24 may be recovered to the outside using the other opening 24a. The recovered liquid may be supplied again from one of the openings 24a, for example, through a filter (not shown). In other words, the ink may be circulated.

[0069] Furthermore, the reservoir 24 according to the embodiment has a structure in which ink supplied from each of the pair of first flow paths 104 joins once at the connection portion 106 and then branches again into a pair of second flow paths 105 from the connection portion 106 .

[0070] This makes it possible to make the ink outlet states of both ink outlets 24b uniform when ink is led out to the branch flow path member 23 from the pair of ink outlets 24b located at both ends.

[0071] Moreover, an opening 103a is formed in the bottom cover 103 of the reservoir 24 according to the embodiment. The opening 103a is formed along the longitudinal direction so as to be connected to the second flow path 105. The opening 103a extends, for example, from the vicinity of one ink outlet 24b to the vicinity of the other ink outlet 24b.

[0072] In addition, since the openings 103a are all blocked by a metal member 26 (see FIG. 6) described later, the ink flowing through the second flow path 105 does not leak from the openings 103a. The details of the metal member 26 will be described later.

[0073] Returning to the explanation of Fig. 3, the reservoir 24 has a side surface facing the heat sink 45 formed with holes 24c for receiving fixing members (not shown) such as screws or bolts.

[0074] The wiring section 30 has a flexible substrate 31, a wiring substrate 32, a plurality of driver ICs 33, and a pressing member 34. The flexible substrate 31 is a flexible wiring substrate, and transmits a predetermined signal sent from the outside to the head body 20. As shown in Fig. 3, the droplet ejection head 8 according to the embodiment has two flexible substrates 31.

[0075] One end of the flexible substrate 31 is electrically connected to the piezoelectric actuator substrate 22 of the head body 20. The other end of the flexible substrate 31 is pulled out above the reservoir 24 and is electrically connected to the wiring substrate 32. This allows the piezoelectric actuator substrate 22 of the head body 20 to be electrically connected to the outside.

[0076] The wiring board 32 is located above the head body 20. The wiring board 32 distributes signals to a plurality of driver ICs 33.

[0077] The multiple driver ICs 33 are located on one main surface of the flexible substrate 31. As shown in Fig. 3, in the droplet ejection head 8 according to the embodiment, two driver ICs 33 are provided on each flexible substrate 31. Note that the number of driver ICs 33 provided on each flexible substrate 31 is not limited to two.

[0078] The driver IC 33 drives each displacement element in the piezoelectric actuator substrate 22 of the head main body 20 based on a drive signal sent from the control unit 14 (see FIG. 1).

[0079] The pressing member 34 is, for example, a leaf spring having a substantially U-shape in cross section. The pressing member 34 is located between the two flexible substrates 31, and presses the driver IC 33 on the flexible substrate 31 toward the heat sink 45.

[0080] As a result, the driver IC 33 comes into close contact with the heat sink 45, and heat generated when the driver IC 33 is driven can be efficiently dissipated to the heat sink 45. The pressing force does not have to be generated directly by the pressing member 34. For example, a force generated by another member may press the driver IC 33 via the pressing member 34.

[0081] The head cover 40 is attached to the head body 20, and is disposed so as to cover the wiring section 30 located on the head body 20, such as the flexible substrate 31, the wiring substrate 32, and the pressing member 34. This enables the head cover 40 to seal the wiring section 30. The head cover 40 is made of, for example, resin or metal.

[0082] The head cover 40 has a box shape that extends long in the main scanning direction, and has a first opening 40a and a second opening 40b on two side surfaces that face each other in the sub-scanning direction (the X-axis direction in the figure). In the example of Fig. 3, the first opening 40a is provided on the side surface located on the X-axis positive direction side, and the second opening 40b is provided on the side surface located on the X-axis negative direction side. In addition, the head cover 40 has a third opening 40c on the bottom surface and a fourth opening 40d on the top surface.

[0083] The two heat sinks 45 are attached to the head cover 40. One of the two heat sinks 45 is disposed so as to cover the first opening 40a, and the other is disposed so as to cover the second opening 40b.

[0084] The heat sink 45 is, for example, a plate-like member that is long in the longitudinal direction of the droplet ejection head 8, and is made of a metal or alloy with high heat dissipation properties. The heat sink 45 is provided so as to be in contact with the driver IC 33, and dissipates heat generated by the driver IC 33.

[0085] Each of the two heat sinks 45 has a plurality of through holes 46 for accommodating fixing members (not shown). The head cover 40 has a plurality of through holes 41 for accommodating such fixing members.

[0086] The two heat sinks 45 are each fixed to the head cover 40 by a fixing member. The head cover 40 to which the heat sinks 45 are attached has a box shape in which the first opening 40a and the second opening 40b are closed and the third opening 40c and the fourth opening 40d are open.

[0087] The third opening 40c is located so as to face the reservoir 24. The flexible substrate 31 and the pressing member 34 are inserted into the third opening 40c.

[0088] The fourth opening 40d is provided for inserting a connector (not shown) provided on the wiring board 32. If the space between the connector and the fourth opening 40d is sealed with resin or the like, it becomes difficult for liquid or dust to enter the inside of the head cover 40.

[0089] Furthermore, the head cover 40 may have a heat insulating portion (not shown) between the heat sink 45 and the head body 20. By providing the head cover 40 with a heat insulating portion, heat generated in the driver IC 33 is less likely to be transmitted to the head body 20 via the heat sink 45.

[0090] Note that FIG. 3 shows an example of the configuration of the droplet ejection head 8, and the droplet ejection head 8 may further include members other than those shown in FIG.

[0091] <Embodiment> Next, a detailed configuration of the droplet ejection head 8 according to the embodiment will be described with reference to Fig. 6 to Fig. 8. Fig. 6 is a cross-sectional view showing an example of the configuration of the branch flow path member 23, the reservoir 24 and their surroundings according to the embodiment, and corresponds to the cross-sectional view taken along the line AA in Fig. 3.

[0092] 6, in the droplet ejection head 8 according to the embodiment, the heater 25, the metal member 26, and the heat conductive member 27 are located between the bottom 23a of the branch flow path member 23 and the bottom lid 103 of the reservoir 24. In the embodiment, the heater 25, the heat conductive member 27, and the metal member 26 are layered in this order between the bottom 23a and the bottom lid 103.

[0093] The heater 25 is located on the upper surface of the bottom 23a, and heats up the inside of the droplet ejection head 8 to a predetermined temperature under the control of the control unit 14 (see FIG. 1), and maintains the temperature at that predetermined temperature. That is, the heater 25 heats up the ink flowing through the inside of the droplet ejection head 8 to a predetermined temperature under the control of the control unit 14, and maintains the temperature at that predetermined temperature.

[0094] This makes it possible to maintain a constant temperature of the droplets discharged from the droplet discharge head 8, thereby maintaining good printing quality of the droplet discharge head 8. The heater 25 is, for example, a film heater.

[0095] Metal member 26 is the second member, and is made of a metal material such as a metal or alloy having high thermal conductivity (for example, stainless steel, 10 W / m·K or more), and is located below bottom cover 103 of reservoir 24 so as to be in contact with the lower surface of bottom cover 103. As a result, metal member 26 is located so as to be in contact with at least a portion of second flow path 105 through opening 103a of bottom cover 103.

[0096] The heat conducting member 27 is located between the heater 25 and the metal member 26 so as to be in contact with both the heater 25 and the metal member 26. The heat conducting member 27 has a relatively high thermal conductivity (for example, 1 W / m·K or more). The heat conducting member 27 is an elastic body such as rubber. The heat conducting member 27 has a higher thermal conductivity than the first member constituting the reservoir base 101.

[0097] In this embodiment, the heater 25 and the metal member 26 are thermally connected via the heat conductive member 27. As a result, excess heat of the heater 25 generated when the droplet ejection head 8 temporarily stops ejecting droplets is transferred to the ink flowing through the second flow path 105 via the heat conductive member 27 and the metal member 26.

[0098] The ink flowing through the second flow path 105 is at approximately room temperature because it has just been supplied to the droplet ejection head 8. Furthermore, since the ink flowing through the second flow path 105 has a large specific heat, in the droplet ejection head 8 according to the embodiment, excess heat of the heater 25 is efficiently cooled by the ink flowing through the second flow path 105.

[0099] That is, in the embodiment, it is possible to reduce the temperature of the droplet ejection head 8 from rising above a predetermined temperature due to excess heat from the heater 25, and therefore, even when droplet ejection is resumed, it is possible to reduce the occurrence of liquid at a temperature higher than the predetermined temperature being ejected as droplets.

[0100] Therefore, according to the embodiment, the printing quality of the droplet ejection head 8 can be improved.

[0101] In addition, in the embodiment, the heater 25 and the metal member 26 may be thermally connected via a thermally conductive member 27 having thermal conductivity. This allows the efficiency of thermal conduction between the heater 25 and the ink flowing through the second flow path 105 to be variously controlled by the thermal conductivity or thickness of the thermal conductive member 27.

[0102] That is, in this embodiment, the heat dissipation property of the excess heat generated by the heater 25 can be further optimized by the heat conductive member 27, so that the printing quality of the droplet ejection head 8 can be further improved.

[0103] In the embodiment, the heat conducting member 27 may be an elastic body. This allows the heat conducting member 27, which is an elastic body, to absorb dimensional variations between the heater 25 and the metal member 26.

[0104] Therefore, according to the embodiment, the excess heat of the heater 25 can be more efficiently transferred to the ink in the second flow path 105, thereby further improving the printing quality of the droplet ejection head 8. Note that in the present disclosure, the heat conductive member 27 is not limited to being an elastic body, and may be a non-elastic body.

[0105] 6, the reservoir 24 and the metal member 26 may be fixed with a nut 28a and a screw 28b. Furthermore, in the embodiment, the second flow path 105 inside the reservoir 24 that contacts the metal member 26 may be sealed with a sealing member 29 located between the metal member 26 and the reservoir 24.

[0106] The sealing member 29 is, for example, an O-ring, and is preferably located inside a groove portion 26b that is formed in an annular shape so as to surround the periphery of the opposing opening portion 103a in the metal member 26.

[0107] For example, when the resin reservoir 24 and the metal member 26 are integrated by insert molding, cracks may occur due to thermal stress depending on the difference in linear expansion coefficient between the resin and the metal.

[0108] On the other hand, in the embodiment, the reservoir 24 and the metal member 26 are integrated with the nut 28a and the screw 28b, so that the occurrence of such cracks can be reduced. Furthermore, in the embodiment, the second flow path 105 is sealed with the sealing member 29, so that the leakage of ink from inside the reservoir 24 can be reduced.

[0109] Therefore, according to the embodiment, the reliability of the droplet ejection head 8 can be improved.

[0110] Fig. 7 is an enlarged perspective view showing an example of the configuration of the fixing part 101a according to the embodiment. As shown in Fig. 7, the reservoir 24 according to the embodiment may have a fixing part 101a for fixing the nut 28a therein. The fixing part 101a is provided, for example, on the lower surface side of the reservoir base 101, and the nut 28a can be fixed by fitting the nut 28a into the fixing part 101a.

[0111] Then, after fitting the nut 28a into the lower surface side of the reservoir base 101, the lower cover 103 is joined to the lower surface of the reservoir base 101, whereby the nut 28a can be easily accommodated inside the reservoir 24. Therefore, according to the embodiment, the manufacturing process of the reservoir 24 can be simplified.

[0112] Returning to the description of Fig. 6, in the embodiment, the screw 28b may be a half screw having a screw portion (not shown) on the tip side and a cylindrical portion (not shown) on the base side. This allows the compressive force of the sealing member 29 to be controlled only by the screw portion on the tip side, so that the shear force generated between the resin reservoir 24 and the metal member 26 made of metal in a high temperature environment can be reduced.

[0113] Therefore, according to the embodiment, damage to the resin reservoir 24 caused by such shear force can be reduced, and the reliability of the droplet ejection head 8 can be improved.

[0114] 6, the metal member 26 may have a protrusion 26a that protrudes from a portion in contact with the second flow path 105 of the reservoir 24 toward the inside of the second flow path 105. In the embodiment, for example, the protrusion 26a is positioned so as to be inserted into almost the entire opening 103a in the lower lid 103.

[0115] This increases the surface area of ​​the metal member 26 in contact with the ink flowing through the second flow path 105, thereby more efficiently transferring excess heat from the heater 25 to the ink in the second flow path 105. Therefore, according to the embodiment, the printing quality of the droplet ejection head 8 can be further improved.

[0116] Fig. 8 is an enlarged cross-sectional view showing an example of the configuration of the reservoir 24 and the metal member 26 according to the embodiment. As shown in Fig. 8, in the embodiment, a gap G may be provided between the convex portion 26a of the metal member 26 and the opening 103a of the second flow path 105. The width of the gap G is, for example, about 0.2 mm to 0.5 mm.

[0117] If the width of the gap G is very narrow (for example, on the order of μm), air bubbles that get into this narrow gap G cannot be easily removed, and there is a risk that such air bubbles will be ejected together with droplets at an unintended timing, which may result in a deterioration in the printing quality of the droplet ejection head 8.

[0118] On the other hand, in the embodiment, by providing the gap G with a width that allows the air bubbles to easily escape, it is possible to reduce the air bubbles being discharged together with the droplets at unintended timing. Therefore, according to the embodiment, it is possible to further improve the printing quality of the droplet discharge head 8.

[0119] 8, a C-surface 103b may be provided on the flow path side of the opening 103a. This allows air bubbles to be more easily removed from between the protrusion 26a and the opening 103a. Therefore, according to the embodiment, the printing quality of the droplet ejection head 8 can be further improved.

[0120] In the present disclosure, the present invention is not limited to the case where the C-face 103b is provided on the flow channel side of the opening 103a, and an R-face may be provided on the flow channel side of the opening 103a.

[0121] <Another embodiment 1> Next, various other embodiments of the present disclosure will be described with reference to Fig. 9 to Fig. 13. Fig. 9 is a cross-sectional view showing an example of the configuration of a branch flow path member 23, a reservoir 24 and their surroundings according to another embodiment 1.

[0122] 9, in a droplet ejection head 8 according to another embodiment 1, the arrangement of the heater 25 and the heat conductive member 27 differs from that of the above-described embodiment (see FIG. 6). Specifically, in another embodiment 1, the heat conductive member 27, the heater 25, and the metal member 26 are layered in this order between the bottom 23a of the branch flow path member 23 and the lower lid 103 of the reservoir 24.

[0123] That is, in Alternative Embodiment 1, the heat conducting member 27 is located on the upper surface of the bottom portion 23a, the heater 25 is located on the upper surface of the heat conducting member 27, and the metal member 26 is in direct contact with the heater 25.

[0124] This also provides a thermal connection between the heater 25 and the metal member 26 in another embodiment 1. As a result, excess heat from the heater 25, which is generated when the droplet ejection head 8 temporarily stops ejecting droplets, is transferred to the ink flowing through the second flow path 105 via the metal member 26. Therefore, the excess heat from the heater 25 is efficiently cooled by the ink flowing through the second flow path 105.

[0125] That is, in another embodiment 1, it is possible to reduce the temperature of the droplet ejection head 8 from rising above a predetermined temperature due to excess heat from the heater 25, and therefore, even when droplet ejection is resumed, it is possible to reduce the occurrence of liquid at a temperature higher than the predetermined temperature being ejected as droplets.

[0126] Therefore, according to the alternative embodiment 1, the printing quality of the droplet ejection head 8 can be improved.

[0127] In addition, in another embodiment 1, as in the above-described embodiment, since the heat conductive member 27 is an elastic body, the dimensional variation between the heater 25 and the metal member 26 can be absorbed by the elastic heat conductive member 27.

[0128] Therefore, according to the alternative embodiment 1, the excess heat of the heater 25 can be more efficiently transferred to the ink in the second flow path 105, so that the printing quality of the droplet ejection head 8 can be further improved.

[0129] In another embodiment 1, the reservoir 24 and the metal member 26 may be fixed with nuts 28a and screws 28b, as in the above embodiment. Furthermore, in another embodiment 1, the second flow path 105 inside the reservoir 24 that contacts the metal member 26 may be sealed with a sealing member 29 located between the metal member 26 and the reservoir 24.

[0130] This can reduce the occurrence of cracks due to thermal stress caused by the difference in linear expansion coefficient between resin and metal. Furthermore, in another embodiment 1, since the second flow path 105 is sealed with the sealing member 29, it can reduce the leakage of ink from the flow path in the reservoir 24. Therefore, according to another embodiment 1, the reliability of the droplet ejection head 8 can be improved.

[0131] In another embodiment 1, similar to the above-described embodiment, the metal member 26 may have a protrusion 26a that protrudes toward the inside of the second flow path 105 from the portion in contact with the second flow path 105 of the reservoir 24.

[0132] This increases the surface area of ​​the metal member 26 in contact with the ink flowing through the second flow path 105, thereby more efficiently transferring excess heat from the heater 25 to the ink in the second flow path 105. Therefore, according to another embodiment 1, the printing quality of the droplet ejection head 8 can be further improved.

[0133] <Another embodiment 2> FIG. 10 is a cross-sectional view showing an example of the configuration of the branch flow path member 23, the reservoir 24 and their surroundings according to another embodiment 2. As shown in FIG.

[0134] 10, in the droplet ejection head 8 according to the second alternative embodiment, the method of joining the reservoir 24 and the metal member 26 is different from that of the above-mentioned embodiment (see FIG. 6). Specifically, in the second alternative embodiment, the lower cover 103 of the reservoir 24 and the metal member 26 are directly joined by a known joining method, such as an adhesive or insert molding, instead of by nuts 28a (see FIG. 6) and screws 28b (see FIG. 6).

[0135] This also provides a thermal connection between the heater 25 and the metal member 26 in the alternative embodiment 2. As a result, excess heat from the heater 25 generated when the droplet ejection head 8 temporarily stops ejecting droplets is transferred to the ink flowing through the second flow path 105 via the thermally conductive member 27 and the metal member 26. Therefore, the excess heat from the heater 25 is efficiently cooled by the ink flowing through the second flow path 105.

[0136] That is, in another embodiment 2, it is possible to reduce the temperature of the droplet ejection head 8 from rising above a predetermined temperature due to excess heat from the heater 25, and therefore, even when droplet ejection is resumed, it is possible to reduce the occurrence of liquid at a temperature higher than the predetermined temperature being ejected as droplets.

[0137] Therefore, according to the second alternative embodiment, the printing quality of the droplet ejection head 8 can be improved.

[0138] In another embodiment 2, similarly to the above-described embodiment, the heat conduction member 27 is an elastic body, so that the dimensional variation between the heater 25 and the metal member 26 can be absorbed by the elastic heat conduction member 27.

[0139] Therefore, according to the second alternative embodiment, the excess heat of the heater 25 can be transferred more efficiently to the ink in the second flow path 105, so that the printing quality of the droplet ejection head 8 can be further improved.

[0140] In another embodiment 2, similar to the above embodiment, the metal member 26 may have a protrusion 26a that protrudes toward the inside of the second flow path 105 from the portion in contact with the second flow path 105 of the reservoir 24.

[0141] This increases the surface area of ​​the metal member 26 in contact with the ink flowing through the second flow path 105, thereby more efficiently transferring excess heat from the heater 25 to the ink in the second flow path 105. Therefore, according to the second alternative embodiment, the printing quality of the droplet ejection head 8 can be further improved.

[0142] <Another embodiment 3> Fig. 11 is a cross-sectional view showing an example of the configuration of the branch flow path member 23, the reservoir 24 and their surroundings according to another embodiment 3. As shown in Fig. 11, in the droplet ejection head 8 according to another embodiment 3, the configuration of the metal member 26 is different from that of the above-mentioned another embodiment 2 (see Fig. 10).

[0143] Specifically, in the third alternative embodiment, the portion of the metal member 26 that contacts the opening 103a is flat, and no protrusion 26a (see FIG. 10) is provided.

[0144] This also provides a thermal connection between the heater 25 and the metal member 26 in the alternative embodiment 3. As a result, excess heat from the heater 25 generated when the droplet ejection head 8 temporarily stops ejecting droplets is transferred to the ink flowing through the second flow path 105 via the thermally conductive member 27 and the metal member 26. Therefore, the excess heat from the heater 25 is efficiently cooled by the ink flowing through the second flow path 105.

[0145] That is, in another embodiment 3, it is possible to reduce the temperature of the droplet ejection head 8 from rising above a predetermined temperature due to excess heat from the heater 25, and therefore, even when droplet ejection is resumed, it is possible to reduce the occurrence of liquid at a temperature higher than the predetermined temperature being ejected as droplets.

[0146] Therefore, according to the third alternative embodiment, the printing quality of the droplet ejection head 8 can be improved.

[0147] In another embodiment 3, similar to the above-described embodiment, the heat conduction member 27 is an elastic body, so that the dimensional variation between the heater 25 and the metal member 26 can be absorbed by the elastic heat conduction member 27.

[0148] Therefore, according to the third alternative embodiment, the excess heat of the heater 25 can be more efficiently transferred to the ink in the second flow path 105, so that the printing quality of the droplet ejection head 8 can be further improved.

[0149] <Another embodiment 4> Fig. 12 is a cross-sectional view showing an example of the configuration of the branch flow path member 23, the reservoir 24 and their surroundings according to another embodiment 4. As shown in Fig. 12, in the droplet ejection head 8 according to another embodiment 4, the configuration of the metal member 26 is different from that of the above-mentioned another embodiment 3 (see Fig. 11). Specifically, in another embodiment 4, a recess 26c is provided in the metal member 26 at a portion that contacts the opening 103a.

[0150] This also provides a thermal connection between the heater 25 and the metal member 26 in the alternative embodiment 4. As a result, excess heat from the heater 25 generated when the droplet ejection head 8 temporarily stops ejecting droplets is transferred to the ink flowing through the second flow path 105 via the thermally conductive member 27 and the metal member 26. Therefore, the excess heat from the heater 25 is efficiently cooled by the ink flowing through the second flow path 105.

[0151] That is, in another embodiment 4, it is possible to reduce the temperature of the droplet ejection head 8 from rising above a predetermined temperature due to excess heat from the heater 25, and therefore, even when droplet ejection is resumed, it is possible to reduce the occurrence of liquid at a temperature higher than the predetermined temperature being ejected as droplets.

[0152] Therefore, according to the fourth alternative embodiment, the printing quality of the droplet ejection head 8 can be improved.

[0153] In addition, in another embodiment 4, the metal member 26 has a recess 26c that is recessed in a direction away from the inside of the second flow path 105 from the portion contacting the second flow path 105 of the reservoir 24, thereby increasing the surface area of ​​the metal member 26 that comes into contact with the ink flowing through the second flow path 105.

[0154] Therefore, according to the fourth alternative embodiment, the excess heat of the heater 25 can be more efficiently transferred to the ink in the second flow path 105, so that the printing quality of the droplet ejection head 8 can be further improved.

[0155] <Another embodiment 5> Fig. 13 is a cross-sectional view showing an example of the configuration of the branch flow path member 23, the reservoir 24 and the surrounding areas according to another embodiment 5. As shown in Fig. 13, in the droplet ejection head 8 according to another embodiment 5, the configuration of the reservoir 24 is different from that of the above-mentioned embodiment (see Fig. 6).

[0156] Specifically, in another embodiment 5, the bottom cover 103 of the reservoir 24 is made of the metal member 26. With this, the metal member 26 is also positioned so as to contact at least a part of the second flow path 105. In addition, in another embodiment 5, the heater 25 and the metal member 26 are thermally connected to each other.

[0157] As a result, excess heat generated in the heater 25 when the droplet ejection head 8 temporarily stops ejecting droplets is transferred to the ink flowing through the second flow path 105 via the heat conductive member 27 and the metal member 26. Therefore, the excess heat of the heater 25 is efficiently cooled by the ink flowing through the second flow path 105.

[0158] That is, in another embodiment 5, it is possible to reduce the temperature of the droplet ejection head 8 from rising above a predetermined temperature due to excess heat from the heater 25, and therefore, even when droplet ejection is resumed, it is possible to reduce the occurrence of liquid at a temperature higher than the predetermined temperature being ejected as droplets.

[0159] Therefore, according to the fifth alternative embodiment, the printing quality of the droplet ejection head 8 can be improved.

[0160] In the fifth alternative embodiment, the metal member 26 also functions as the lower cover 103, so that the surface area of ​​the metal member 26 that comes into contact with the ink flowing through the second flow path 105 can be increased.

[0161] Therefore, according to the fifth alternative embodiment, the excess heat of the heater 25 can be more efficiently transferred to the ink in the second flow path 105, so that the printing quality of the droplet ejection head 8 can be further improved.

[0162] In another embodiment 5, similarly to the above-described embodiment, the heat conduction member 27 is an elastic body, so that the dimensional variation between the heater 25 and the metal member 26 can be absorbed by the elastic heat conduction member 27.

[0163] Therefore, according to the fifth alternative embodiment, the excess heat of the heater 25 can be more efficiently transferred to the ink in the second flow path 105, so that the printing quality of the droplet ejection head 8 can be further improved.

[0164] In another embodiment 5, the reservoir base 101 of the reservoir 24 and the metal member 26 may be directly joined by a known joining method, such as an adhesive or insert molding, or may be mechanically connected using nuts and screws.

[0165] Also, in the embodiment, a mode in which ink is supplied from the outside to the reservoir 24 during printing, and a mode in which ink is supplied from the outside to the reservoir 24 and ink is collected from the reservoir 24 to the outside are described. In the latter mode, ink may be further supplied from the reservoir 24 to the flow path member 21 and ink may be collected from the flow path member 21 to the reservoir 24.

[0166] Furthermore, ink may be supplied to and recovered from the flow path facing the nozzle (ejection hole) in the flow path member 21, so that ink is less likely to accumulate in the nozzle and around the nozzle. In such an embodiment, ink is supplied from the outside to the droplet ejection head 8 as a whole, some of the ink is ejected, and the ink that is not ejected is recovered to the outside.

[0167] The ink recovered outside may be supplied again to the droplet ejection head 8. In other words, the ink may be circulated. The supply and recovery of the ink to the droplet ejection head 8, or the circulation of the ink may be controlled by the control unit 14.

[0168] Although the embodiments of the present disclosure have been described above, the present disclosure is not limited to the above-described embodiments, and various modifications are possible without departing from the spirit of the present disclosure.

[0169] Further advantages and other aspects may readily occur to those skilled in the art. Thus, the disclosure 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 equivalents thereof.

[0170] The present technology can also be configured as follows. (1) a flow path member having a plurality of ejection holes through which droplets are ejected; a reservoir located above the flow path member and supplying liquid to the flow path member; a heater located between the flow path member and the reservoir, the heater heating the liquid supplied to the flow path member; a metal member located in the reservoir so as to contact at least a portion of the flow path extending along a surface of the reservoir facing the flow path member; Equipped with The heater and the metal member are directly or indirectly thermally connected to each other. Droplet ejection head. (2) The heater and the metal member are thermally connected via a heat conductive member having thermal conductivity. The droplet ejection head according to (1) above. (3) The heat conducting member is an elastic body. The droplet ejection head according to (2) above. (4) The reservoir and the metal member are fixed together with nuts and screws, The flow path in the reservoir that contacts the metal member is sealed with a sealing member located between the metal member and the reservoir. The droplet ejection head according to any one of (1) to (3) above. (5) The reservoir has a fixing portion for fixing the nut therein. The droplet ejection head according to (4) above. (6) The screw is a half screw having a threaded portion at the distal end and a cylindrical portion at the proximal end. The droplet ejection head according to (4) or (5) above. (7) The metal member has a protrusion that protrudes toward the inside of the flow channel from a portion of the reservoir that contacts the flow channel. The droplet ejection head according to any one of (1) to (6) above. (8) A gap is provided between the protrusion of the metal member and the opening of the flow path corresponding to the protrusion. The droplet ejection head according to (7) above. (9) A C-face is provided on the flow channel side of the opening of the flow channel corresponding to the convex portion. The droplet ejection head according to (7) or (8) above. (10) The metal member has a recess that is recessed in a direction away from the inside of the flow channel from a portion of the reservoir that contacts the flow channel. The droplet ejection head according to any one of (1) to (6) above. (11) The droplet ejection head according to any one of (1) to (10), A control unit for controlling the droplet ejection head; A droplet ejection device comprising: [Explanation of symbols]

[0171] 1. Printer (an example of a droplet ejection device) 8 Droplet ejection head 14 Control section 21 Flow path components 23 Branching flow path member 24 Reservoir 25 Heater 26 Metallic parts 26a Convex 26c Recess 27 Thermal Conductive Materials 28a Nut 28b Screw 29 Sealing member 101 Reservoir Base 102 Top lid 103 Lower lid 103a opening 103b C side 104 First Channel 105 Second flow path (an example of a flow path) 106 Connection G Gap

Claims

1. a flow path member having a plurality of ejection holes through which droplets are ejected; a reservoir located above the flow path member and supplying liquid to the flow path member; a heater located between the flow path member and the reservoir, the heater heating the liquid supplied to the flow path member; a metal member located in the reservoir so as to contact at least a portion of the flow path extending along a surface of the reservoir facing the flow path member; Equipped with The heater and the metal member are thermally connected directly or indirectly. Droplet ejection head.

2. The heater and the metal member are thermally connected via a heat conductive member having thermal conductivity. The droplet ejection head according to claim 1 .

3. The heat conducting member is an elastic body. The droplet ejection head according to claim 2 .

4. The reservoir and the metal member are fixed together with nuts and screws, The flow path in the reservoir that contacts the metal member is sealed with a sealing member located between the metal member and the reservoir.

4. The droplet ejection head according to claim 1.

5. The reservoir has a fixing portion for fixing the nut therein. The droplet ejection head according to claim 4 .

6. The screw is a half screw having a threaded portion at the distal end and a cylindrical portion at the proximal end. The droplet ejection head according to claim 4 .

7. The metal member has a protrusion that protrudes toward the inside of the flow channel from a portion of the reservoir that contacts the flow channel.

4. The droplet ejection head according to claim 1.

8. A gap is provided between the protrusion of the metal member and the opening of the flow path corresponding to the protrusion. The droplet ejection head according to claim 7.

9. A chamfered surface is provided on the flow channel side of the opening of the flow channel corresponding to the convex portion. The droplet ejection head according to claim 7.

10. The metal member has a recess that is recessed in a direction away from the inside of the flow channel from a portion of the reservoir that contacts the flow channel.

4. The droplet ejection head according to claim 1.

11. A droplet ejection head according to any one of claims 1 to 3, A control unit for controlling the droplet ejection head; A droplet ejection device comprising:

Images