Liquid ejecting head and liquid ejecting apparatus

Abstract

A liquid ejecting head and a liquid ejecting apparatus in which a head chip is effectively heated by a heater. The liquid ejecting head is supported on a support body and includes: a first head chip that ejects a liquid; a holder that has a holding portion that holds the first head chip and a flange portion that contacts the support body at a position apart from the holding portion; and a heater that heats the holding portion, the holding portion having a heat receiving portion that receives heat from the heater, a shortest path of heat transferred in the holder from the heat receiving portion to the flange portion being bent or curved at two or more places.

Description

TECHNICAL FIELD

[0001] The present application relates to a liquid ejection head and a liquid ejection apparatus. BACKGROUND

[0002] In a liquid ejection apparatus typified by an inkjet printer, a liquid ejection head that ejects a liquid such as ink as droplets is generally provided. The liquid ejection head is supported on a support body, for example, as a head unit described in Patent Literature 1.

[0003] The head unit described in Patent Literature 1 has a plurality of drive sections having nozzles that eject ink, and a holder that holds the plurality of drive sections, and these components are composed of a conductive material such as metal for the purpose of grounding.

[0004] However, sometimes a heater that heats a liquid is provided in the liquid ejection head, for example, as an inkjet recording head described in Patent Literature 2.

[0005] In a structure in which the heater of Patent Literature 2 is applied to the head unit described in Patent Literature 1, there is a problem in that heat from the heater easily spreads to the support body via the holder, as a result of which the drive sections cannot be effectively heated by the heater.

[0006] Patent Literature 1: Japanese Patent Application Publication No. 2017-185739

[0007] Patent Literature 2: Japanese Patent Application Publication No. 2010-214879 SUMMARY

[0008] To solve the above problems, a liquid ejection head according to a preferred embodiment of the present application is a liquid ejection head supported on a support body, and includes: a first head chip that ejects a liquid; a holder that has a holding section that holds the first head chip and a flange section that contacts the support body at a position separate from the holding section; and a heater that heats the holding section, the holding section having a heat receiving section that receives heat from the heater, a shortest path of heat transferred in the holder from the heat receiving section to the flange section being bent or curved at two or more places.

[0009] The liquid ejecting head according to the preferred embodiment of the present application is a liquid ejecting head supported on a support body, and includes: a head chip having a nozzle face on which nozzles that eject liquid in an ejection direction are provided; a holder that holds the head chip, has a flange portion that contacts the support body at a position apart from the head chip, an outer wall portion that is connected to the flange portion and surrounds the head chip when viewed in the ejection direction, and a connecting portion that connects the head chip and the outer wall portion, the head chip protrudes from the connecting portion in a direction opposite to the ejection direction, and the outer wall portion extends from the connecting portion toward the flange portion in a direction opposite to the ejection direction; and a heater that heats the head chip.

[0010] The liquid ejecting apparatus according to the preferred embodiment of the present application includes: the liquid ejecting head according to any one of the above-described embodiments; and a support body that supports the liquid ejecting head. BRIEF DESCRIPTION OF DRAWINGS

[0011] Figure 1 A diagram showing an outline of the structure of the liquid ejecting apparatus according to the first embodiment.

[0012] Figure 2 A perspective view of the liquid ejecting head and the support body according to the first embodiment.

[0013] Figure 3 An exploded perspective view of the liquid ejecting head according to the first embodiment.

[0014] Figure 4 A cross-sectional view taken along line A-A in FIG. Figure 2

[0015] A cross-sectional view taken along line B-B in FIG. Figure 5 Figure 2 A cross-sectional view taken along line B-B in FIG.

[0016] Figure 6 A cross-sectional view taken along line B-B in FIG.

[0017] Figure 7 A bottom view of the holder according to the first embodiment.

[0018] Figure 8 A top view of the holder according to the first embodiment.

[0019] Figure 9 A diagram for explaining the shape of the holder portion of the holder according to the first embodiment.

[0020] Figure 10 ​FIG. 1 is a diagram for explaining the shape of the heater and the heat conductive member in the first embodiment.

[0021] Figure 11 FIG. 2 is a diagram for explaining the heat transfer path from the heater in the first embodiment.

[0022] Figure 12 FIG. 3 is an exploded perspective view of the liquid ejection head related to the second embodiment.

[0023] Figure 13 FIG. 4 is a diagram for explaining the heat transfer path from the heater in the third embodiment. DETAILED DESCRIPTION

[0024] Hereinafter, preferred embodiments related to the present application will be described with reference to the accompanying drawings. Note that in the drawings, the size and the scale of each part are appropriately different from the actual ones, and there are parts that are schematically shown for the sake of convenience. Furthermore, the scope of the present application is not limited to these modes as long as there is no description in the following description that is intended to particularly limit the present application.

[0025] For the sake of convenience, the following description will be given using X-axis, Y-axis, and Z-axis that cross each other. Furthermore, in the following description, one direction along the X-axis is XI direction, and the direction opposite to the XI direction is X2 direction. Similarly, the directions opposite to each other along the Y-axis are Yl direction and Y2 direction. Furthermore, the directions opposite to each other along the Z-axis are Zl direction and Z2 direction. Furthermore, the case of observing in the Z-axis direction will be sometimes simply referred to as "plan view observation". In addition, the Y direction or the Y2 direction is one example of the "first direction". The XI direction or the X2 direction is one example of the "second direction".

[0026] Here, typically, the Z-axis is an upright axis, and the Z2 direction corresponds to the downward direction in the upright direction. However, the Z-axis can not be an upright axis. Furthermore, although the X-axis, the Y-axis, and the Z-axis are typically orthogonal to each other, they are not limited thereto, and for example, they can cross at an angle in the range of 80 degrees or more and 100 degrees or less.

[0027] 1. First Embodiment

[0028] 1-1. Outline structure of liquid ejection device

[0029] Figure 1A schematic diagram of a configuration example of a liquid ejecting apparatus 100 according to the first embodiment will be described. The liquid ejecting apparatus 100 is a printing apparatus of an inkjet method that ejects ink, which is an example of a liquid, as droplets toward a medium M. The medium M is typically a print paper. Note that the medium M is not limited to a print paper, and can be a print object of an arbitrary material such as a resin film or cloth.

[0030] As shown in FIG. 1, the liquid ejecting apparatus 100 includes a liquid storage portion 10, a control unit 20, a conveyance mechanism 30, a moving mechanism 40, and a liquid ejecting head 50. Figure 1

[0031] The liquid storage portion 10 is a container that stores ink. As a specific example of the liquid storage portion 10, a cartridge that can be attached to and detached from the liquid ejecting apparatus 100, an ink bag that is a bag-shaped container formed of a flexible film, an ink tank that can be refilled with ink, and the like can be given.

[0032] Although not shown, the liquid storage portion 10 has a plurality of containers that store ink of different colors from each other. As ink stored in the plurality of containers, although not particularly limited, for example, cyan ink, magenta ink, yellow ink, black ink, clear ink, white ink, a treatment liquid, and the like can be given, and a combination of two or more of them can be used. Note that the composition of the ink is not particularly limited, and for example, can be an aqueous ink in which a color material such as a dye or a pigment is dissolved in a water-based solvent, a solvent ink in which a color material is dissolved in an organic solvent, or an ultraviolet-curable ink.

[0033] In the present embodiment, a configuration using four kinds of ink different from each other is exemplified. The four kinds of ink are, for example, ink of different colors from each other such as cyan ink, magenta ink, yellow ink, and black ink.

[0034] The control unit 20 controls the operation of each element of the liquid ejecting apparatus 100. For example, the control unit 20 includes a processing circuit such as a CPU (Central Processing Unit) or an FPGA (Field Programmable Gate Array) and a storage circuit such as a semiconductor memory. The control unit 20 outputs a drive signal D and a control signal S to the liquid ejecting head 50. The drive signal D is a signal including a drive pulse that drives a drive element of the liquid ejecting head 50. The control signal S is a signal that specifies whether or not to supply the drive signal D to the drive element.

[0035] ​The conveying mechanism 30, under the control of the control unit 20, conveys the medium M in the conveying direction DM, which is the Y1 direction. The moving mechanism 40, under the control of the control unit 20, causes the liquid injection head 50 to reciprocate in the X1 and X2 directions. Figure 1 In the example shown, the moving mechanism 40 has a generally box-shaped support 41, called a carriage, which houses the liquid injection head 50, and a conveyor belt 42 that fixes the support 41. In addition to the liquid injection head 50, the aforementioned liquid reservoir 10 may also be mounted on the support 41.

[0036] As described below, the liquid jetting head 50 has a plurality of nozzles 54. Under the control of the control unit 20, ink supplied from the liquid reservoir 10 is jetted from each of the plurality of nozzles of the nozzles 54 toward the medium M in the Z2 direction, which is the jetting direction. This jetting is performed in parallel with the transport of the medium M by the transport mechanism 30 and the reciprocating movement of the liquid jetting head 50 by the moving mechanism 40, thereby forming a predetermined image produced by the ink on the surface of the medium M.

[0037] Alternatively, the liquid reservoir 10 can be connected to the liquid jet head 50 via a circulation mechanism. This circulation mechanism supplies ink to the liquid jet head 50 and recovers ink discharged from the liquid jet head 50 for resupply. The operation of this circulation mechanism can suppress the increase in ink viscosity or reduce the retention of air bubbles within the ink.

[0038] 1-2. Installation status of the liquid injection head

[0039] Figure 2 This is a perspective view of the liquid injection head 50 and the support body 41 according to the first embodiment. Figure 2 As shown, the liquid injection head 50 is supported on the support body 41. The support body 41 is a component that supports the liquid injection head 50, and as described above, in this embodiment, it is a generally box-shaped carriage. While not particularly limited in its constituent material, the support body 41 is preferably made of metal materials such as stainless steel, aluminum, titanium, or magnesium alloy. When the support body 41 is made of a metal material, its rigidity is easily increased, thus enabling stable support of the liquid injection head 50 relative to the support body 41. Furthermore, in this case, since the support body 41 is conductive, a reference potential can be supplied to the liquid injection head 50 via the support body 41.

[0040] In the support body 41, an opening 41a and a plurality of screw holes 41b are provided. In the present embodiment, the support body 41 is substantially box-shaped having a plate-shaped bottom portion, and the opening 41a and the plurality of screw holes 41b are provided at the bottom portion, for example. The liquid ejecting head 50 is fixed to the support body 41 by screwing using the plurality of screw holes 41b in a state of being inserted into the opening 41a. In this manner, the liquid ejecting head 50 is mounted with respect to the support body 41.

[0041] In Figure 2 the example illustrated, the number of liquid ejecting heads 50 mounted on the support body 41 is one. In addition, the number of liquid ejecting heads 50 mounted on the support body 41 can also be two or more. In this case, in the support body 41, an opening 41a of a number or a shape corresponding to the number is appropriately provided, for example.

[0042] 1-3. Structure of liquid ejecting head

[0043] Figure 3 An exploded perspective view of the liquid ejecting head 50 according to the first embodiment. Figure 4 An A-A line cross-sectional view of Figure 2 . In Figure 5 a B-B line cross-sectional view of Figure 2 . In Figure 3 to Figure 5 , for convenience, each part of the liquid ejecting head 50 is appropriately and simply illustrated. For example, although a gap with a gap d2 between the outer wall portion 5b and the flow channel structure 51 is illustrated in Figure 11 as described later, in Figure 4 and Figure 5 , the illustration of the gap is omitted for convenience of drawing.

[0044] As illustrated in Figure 3 , the liquid ejecting head 50 has the flow channel structure 51, the substrate unit 52, the holder 53, the four head chips 54_1 to 54_4, the fixing plate 55, the heater 56, the heat conductive member 57, and the cover 58. These components are arranged in a manner that the cover 58, the substrate unit 52, the flow channel structure 51, the heat conductive member 57, the heater 56, the holder 53, the four head chips 54, and the fixing plate 55 are arranged side by side in the Z2 direction. Hereinafter, each part of the liquid ejecting head 50 will be described in order.

[0045] In addition, the heat conductive member 57 is one example of a "second heat conductive member". Furthermore, the head chips 54_1 to 54_4 are each an example of a "head chip". Figure 1The head chip 54_1 is an example of a "first head chip". The head chip 54_2 is an example of a "second head chip". The head chip 54_3 is an example of a "third head chip". The head chip 54_4 is an example of a "fourth head chip". Hereinafter, each of these chips is labeled as the head chip 54 without distinguishing the head chips 54_1 to 54_4.

[0046] The flow path structure 51 is a structure in which flow paths for supplying the four head chips 54 with the inks stored in the aforementioned liquid storage portion 10 are provided inside. The flow path structure 51 has a flow path member 51a and eight connection tubes 51b.

[0047] In the flow path member 51a, although not shown, four supply flow paths provided for each of the four kinds of inks and four discharge flow paths provided for each of the four kinds of inks are provided. Each of the four supply flow paths has one inlet port that receives the supply of the ink and two outlet ports that discharge the ink. Each of the four discharge flow paths has two inlet ports that receive the supply of the ink and one outlet port that discharges the ink. The inlet port of each of the supply flow paths and the outlet port of each of the discharge flow paths are provided on a face of the flow path member 51a that faces the Zl direction, respectively. In contrast, the outlet port of each of the supply flow paths and the inlet port of each of the discharge flow paths are provided on a face of the flow path member 51a that faces the Z2 direction, respectively.

[0048] Further, in the flow path member 51a, a plurality of wiring holes 51c are provided. Each of the plurality of wiring holes 51c is a hole through which a later-described wiring substrate 54i of the head chip 54 passes toward the substrate unit 52. In addition, on a side surface of the flow path member 51a, a portion in which cutouts are provided at two places in the circumferential direction is provided. Inside a space formed by this portion, for example, a not-shown wiring or the like member that connects the heater 56 and the substrate unit 52 is disposed. Further, a not-shown hole is provided in the flow path member 51a, and the flow path member 51a is fixed with respect to the holder 53 by screwing using this hole.

[0049] Although not shown, the flow path member 51a is composed of a laminate in which a plurality of substrates are laminated in the direction along the Z axis. In each of the plurality of substrates, grooves and holes for the aforementioned supply flow paths and discharge flow paths are appropriately provided. The plurality of substrates are joined to each other, for example, by an adhesive, soldering, welding, or screwing, or the like. In addition, between the plurality of substrates, a sheet-shaped sealing member composed of a rubber material or the like can be appropriately disposed as needed. Further, the number or thickness of the substrates that compose the flow path member 51a and the like are determined in accordance with the shapes of the supply flow paths and the discharge flow paths and the like, and are not particularly limited and are arbitrary.

[0050] As a material constituting each of the plurality of substrates, it is preferable to use a material having good thermal conductivity, for example, it is preferable to use a metal material such as stainless steel, titanium, and magnesium alloy, or a ceramic material such as silicon carbide, aluminum nitride, sapphire, alumina, silicon nitride, metal ceramic, and yttrium oxide, having a thermal conductivity of 10.0 W / m-K or more at room temperature (20°C). By constituting the flow passage member 51a with such a metal material or a ceramic material, it is possible to efficiently heat the ink in the flow passage member 51a by the heat from the heater 56.

[0051] Each of the eight connection pipes 51b is a pipe body that protrudes from the face of the flow passage member 51a facing the Zl direction. The eight connection pipes 51b correspond to the aforementioned four supply flow passages and four discharge flow passages, and are connected to the inlet port of the corresponding supply flow passage or the outlet port of the discharge flow passage. As a material constituting each of the connection pipes 51b, although not particularly limited, for example, it is preferable to use a metal material such as stainless steel, titanium, and magnesium alloy, or a ceramic material such as silicon carbide, aluminum nitride, sapphire, alumina, silicon nitride, metal ceramic, and yttrium oxide.

[0052] The four connection pipes 51b among the above eight connection pipes 51b that correspond to the aforementioned four supply flow passages are connected to the aforementioned liquid reservoir 10 in a manner that accepts the supply of mutually different kinds of ink. On the other hand, the four connection pipes 51b among the eight connection pipes 51b that correspond to the aforementioned four discharge flow passages are used in a manner connected to a discharge container for discharging ink at predetermined times such as when initially filling the ink to the liquid ejection head 50, or a sub tank or the like that is disposed between the liquid reservoir 10 and the liquid ejection head 50 and can hold liquid. At ordinary times such as during printing, the four connection pipes 51b that correspond to the aforementioned four discharge flow passages are plugged by a seal such as a cap. In addition, in the case where the liquid reservoir 10 is connected to the liquid ejection head 50 via a circulation mechanism, the four connection pipes 51b that correspond to the four discharge flow passages are connected to the flow passage for ink recovery of the circulation mechanism at ordinary times.

[0053] The substrate unit 52 is an assembly having a mounting member for electrically connecting the liquid ejection head 50 to the control unit 20. The substrate unit 52 has a circuit substrate 52a, a connector 52b, and a support plate 52c.

[0054] The circuit substrate 52a is a rigid wiring substrate or the like printed wiring substrate having a wiring for electrically connecting each head chip 54 and the connector 52b. The circuit substrate 52a is disposed on the flow passage structure 51 via the support plate 52c, and the connector 52b is provided on the face of the circuit substrate 52a facing the Zl direction.

[0055] The connector 52b is a connecting member for electrically connecting the liquid ejection head 50 and the control unit 20. The support plate 52c is a plate-shaped member for mounting the circuit board 52a with respect to the flow passage structure 51. The circuit board 52a is placed on one face of the support plate 52c, and is fixed to the support plate 52c by screwing or the like. Further, the other face of the support plate 52c is in contact with the flow passage structure 51, and in this state, the support plate 52c is fixed to the flow passage structure 51 by screwing or the like.

[0056] Here, the support plate 52c has not only a function of supporting the circuit board 52a as described above, but also a function of ensuring electrical insulation between the circuit board 52a and the flow passage structure 51 and thermally insulating the heater 56 from the circuit board 52a. From the viewpoint of appropriately exerting these functions, the material constituting the support plate 52c is preferably a material excellent in insulation and thermal insulation, and specifically, for example, a modified polyphenylene ether resin such as Zylon, a polyphenylene sulfide resin, a polypropylene resin, or the like is preferred. Note that Zylon is a registered trademark. Further, in the material constituting the support plate 52c, in addition to the resin material, a fiber base material such as glass fiber or a filler such as alumina particles can be contained.

[0057] The holder 53 is a structure for housing and supporting the four head chips 54. As the material constituting the holder 53, a material excellent in thermal conductivity is preferably used, and for example, a metal material such as stainless steel, titanium, and magnesium alloy, or a ceramic material such as silicon carbide, aluminum nitride, sapphire, alumina, silicon nitride, metal ceramic, and yttrium oxide having a thermal conductivity of 10.0 W / m-K or more at room temperature (20°C) is preferably used. By constituting the holder 53 with such a metal material or a ceramic material, heat from the heater 56 can be efficiently transmitted to each head chip 54 via the holder 53.

[0058] The retainer 53 is generally tray-shaped and has a recess 53a, a plurality of ink holes 53b, a plurality of wiring holes 53c, a plurality of recesses 53d, a plurality of threaded holes 53i, and a plurality of threaded holes 53k. The recess 53a opens towards the Z1 direction and serves as a space for the laminate containing the aforementioned flow channel component 51a, heater 56, and heat-conducting component 57. Each of the plurality of ink holes 53b is a flow channel for ink to flow between the head chip 54 and the flow channel structure 51. Each of the plurality of wiring holes 53c is a hole through which the wiring substrate 54i of the head chip 54 passes towards the substrate unit 52. Each of the plurality of recesses 53d opens towards the Z2 direction and serves as a space for the head chip 54. The plurality of threaded holes 53i are threaded holes for threadedly securing the retainer 53 relative to the support body 41. The plurality of threaded holes 53k are threaded holes for threadedly securing the cover 58 relative to the retainer 53. Furthermore, details regarding the retainer 53 will be provided later. Figure 7 of Figure 9 And then an explanation will be given.

[0059] Each head chip 54 ejects ink. Each head chip 54 has multiple nozzles for ejecting a first ink and multiple nozzles for ejecting a second ink of a different type than the first ink. Here, the first ink and the second ink are two of the aforementioned four types of ink. For example, in each of head chips 54_1 and 54_2, two of the four types of ink are used as the first ink and the second ink. Moreover, in each of head chips 54_3 and 54_4, the remaining two of the four types of ink are used. A wiring board 54i is provided in each head chip 54. In addition, in Figure 3 The structure of each head chip 54 is simplified and illustrated in the figure. The structure of the head chip 54 will be discussed later. Figure 6 And then a detailed description will be given.

[0060] The fixing plate 55 is a plate-shaped component that holds four head chips 54 and a retainer 53. Specifically, the fixing plate 55 is configured to hold the four head chips 54 between itself and the retainer 53, and each head chip 54 and the retainer 53 are fixed by adhesive or the like.

[0061] The fixing plate 55 has multiple openings 55a that expose the nozzle surfaces FN of the four head chips 54. Figure 3In the illustrated example, the plurality of opening portions 55a are provided independently for each head chip 54. The fixing plate 55 is composed of, for example, a metal material such as stainless steel, titanium, and a magnesium alloy, and has a function of transmitting heat from the holder 53 to each head chip 54. Further, the fixing plate 55 has electrical conductivity. Therefore, the fixing plate 55 is grounded via the holder 53 and the support body 41, and functions also as an electrostatic shield for preventing the influence of static electricity and the like from the medium M. In addition, the fixing plate 55 can be composed by laminating a plurality of plate-shaped members composed of a metal material.

[0062] The outer shape of the fixing plate 55 described above is rectangular or substantially rectangular when viewed from above. Here, "substantially rectangular" means a concept including a shape that can be substantially called a rectangle and a shape similar to a rectangle. The shape that can be substantially called a rectangle is, for example, a shape obtained by chamfering the four corners of a rectangle, such as C-chamfering or R-chamfering. The shape similar to a rectangle is, for example, a shape like an octagon that includes four sides along the four sides of a rectangle and four sides that are shorter than each of the four sides. In addition, the opening portion 55a can also be of a type shared by two or more head chips 54. However, in the case where the opening portion 55a is provided independently for each head chip 54, since it is easy to increase the contact area of the fixing plate 55 with each head chip 54, it is possible to efficiently transmit heat from the holder 53 to each head chip 54.

[0063] The heater 56 is a planar heater disposed between the flow passage structure 51 and the holder 53. The heater 56 is, for example, a thin film heater having a thin film of an insulating property and a thin film-shaped heating resistor. The thin film is composed of, for example, a resin material such as polyimide or PET (polyethylene terephthalate). The heating resistor is patterned on the thin film and is composed of, for example, a metal material such as stainless steel or copper or a nickel alloy. Further, the heater 56 can also be a planar heater such as a silicone rubber heater or a ceramic heater in which a heating element is sandwiched between silicone rubber containing glass fibers.

[0064] A plurality of holes 56a and a plurality of holes 56b are provided in the heater 56. Each of the plurality of holes 56a is a hole through which the wiring substrate 54i of the head chip 54 and the flow channel pipe 53l formed in the holder 53 pass. The ink hole 53b formed in the inside of the flow channel pipe 53l is a portion of the flow channel that allows the ink to flow between the head chip 54 and the flow channel structure 51. The flow channel pipe 53l protrudes in the Zl direction, for example, from the upper surface (first surface Fl, described later) of the holder 53 facing the Zl direction. Also, the ink hole 53b and the flow channel in the inside of the flow channel structure 51 are liquid-tightly sealed by the tip of the flow channel pipe 53l on the Zl direction side being bonded to the lower surface of the flow channel structure 51 facing the Z2 direction. Each of the plurality of holes 56b is a hole for threadably fixing the heater 56 with respect to the holder 53. In addition, regarding the plan view shape of the heater 56, it will be based on the plan view shape of the flow channel structure 51 described later Figure 10 , which will be described in detail.

[0065] The thermally conductive member 57 is a plate-shaped member having thermal conductivity and is disposed between the flow channel structure 51 and the heater 56. The thermally conductive member 57 has a function of transmitting heat in each of the thickness direction and the surface direction. According to this function, heat from the heater 56 is efficiently transmitted to the flow channel structure 51 via the thermally conductive member 57. Here, by the thermal conduction in the surface direction of the thermally conductive member 57, heating unevenness of the flow channel structure 51 due to the heat generation distribution of the heater 56 is reduced.

[0066] The thermally conductive member 57 is composed of a material having thermal conductivity such as a metal material or a ceramic such as silicon carbide, aluminum nitride, sapphire, alumina, silicon nitride, metal ceramic, and yttrium oxide, for example. As the metal material, for example, stainless steel, aluminum, titanium, and magnesium alloy, and the like can be listed. It is preferable that the thermally conductive member 57 be a material having a high thermal conductivity with respect to the flow channel structure 51 or the holder 53. Since the heat from the heater 56 is easily moved in a direction parallel to the nozzle surface FN by having such a thermally conductive member 57 having a high thermal conductivity, the heat from the heater 56 can be uniformly and efficiently transmitted to the flow channel structure 51 as a heating target via the thermally conductive member 57.

[0067] The heat-conducting component 57 is provided with a plurality of holes 57a, a plurality of wiring holes 57b, and a plurality of holes 57c. Each of the plurality of holes 57a is a hole through which the aforementioned flow channel tube 53l is inserted. Each of the plurality of wiring holes 57b is a hole through which the wiring substrate 54i of the head chip 54 passes toward the substrate unit 52. The plurality of holes 57c are holes for threading the heat-conducting component 57 relative to the holder 53. In this embodiment, two of the plurality of holes 57c are used to fix the heater 56 and the heat-conducting component 57 to the holder 53 by tightening them together. Furthermore, the top view shape of the heat-conducting component 57 will be based on the following description. Figure 10 A detailed description will be provided.

[0068] The cover 58 is a box-shaped component that houses the substrate unit 52. The cover 58 is made of resin materials such as modified polyphenylene ether resin, polyphenylene sulfide resin, and polypropylene resin, for example, similar to the aforementioned support plate 52c.

[0069] The cover 58 has eight through holes 58a and openings 58b. The eight through holes 58a correspond to the eight connecting pipes 51b of the flow channel structure 51, and the corresponding connecting pipe 51b is inserted into each through hole 58a. In the openings 58b, the aforementioned connector 52b passes through from the inside to the outside of the cover 58.

[0070] 1-4. Structure of the head chip

[0071] Figure 6 This is a cross-sectional view showing an example of head chip 54. (See attached image.) Figure 6 As shown, the head chip 54 has a plurality of nozzles N arranged along the Y-axis. The plurality of nozzles N are divided into a first column L1 and a second column L2 arranged side by side with intervals between them along the X-axis. The first column L1 and the second column L2 are sets of a plurality of nozzles N arranged in a straight line along the Y-axis.

[0072] The head chip 54 has a structure that is approximately symmetrical to each other along the X-axis. However, the positions of the plurality of nozzles N in the first column L1 and the plurality of nozzles N in the second column L2 along the Y-axis can be either consistent or different. Figure 6 The diagram illustrates a structure in which the positions of multiple nozzles N in the first column L1 and multiple nozzles N in the second column L2 are aligned along the Y-axis.

[0073] like Figure 6 As shown, the head chip 54 has a flow channel substrate 54a, a pressure chamber substrate 54b, a nozzle plate 54c, a vibration absorber 54d, a vibration plate 54e, multiple piezoelectric elements 54f, a protection plate 54g, a housing 54h, a wiring substrate 54i, and a drive circuit 54j.

[0074] The flow channel substrate 54a and the pressure chamber substrate 54b are sequentially laminated in the Z1 direction to form a flow channel for supplying ink to a plurality of nozzles N. In the region located in the Z1 direction relative to the laminate formed by the flow channel substrate 54a and the pressure chamber substrate 54b, a vibrating plate 54e, a plurality of piezoelectric elements 54f, a protective plate 54g, a housing 54h, a wiring substrate 54i, and a drive circuit 54j are provided. On the other hand, in the region located in the Z2 direction relative to the laminate, a nozzle plate 54c and a vibration absorber 54d are provided. Each element of the head chip 54 is a plate-shaped component that is generally elongated in the Y direction and is joined together by, for example, an adhesive. Hereinafter, each element of the head chip 54 will be described in turn.

[0075] The nozzle plate 54c is a plate-shaped component having a plurality of nozzles N arranged in a first column L1 and a second column L2. Each of the plurality of nozzles N is a through hole through which ink passes. Here, the surface of the nozzle plate 54c facing the Z2 direction is the nozzle surface FN. That is, the normal direction of the nozzle surface FN is the direction of the normal vector of the nozzle surface FN, and is the jetting direction, i.e., the Z2 direction. The nozzle plate 54c is manufactured, for example, by processing a single-crystal silicon substrate using semiconductor manufacturing techniques such as dry etching or wet etching. However, other known methods and materials may also be appropriately used in the manufacture of the nozzle plate 54c. Furthermore, although the cross-sectional shape of the nozzle is typically circular, it is not limited to this; for example, it may be a non-circular shape such as a polygon or an ellipse.

[0076] In the flow channel substrate 54a, for each of the first column L1 and the second column L2, a space R1, a plurality of supply flow channels Ra, and a plurality of connecting flow channels Na are provided. When viewed from above along the Z-axis, the space R1 is an elongated opening extending along the Y-axis. The supply flow channels Ra and connecting flow channels Na are through holes formed for each nozzle N. Each supply flow channel Ra communicates with the space R1.

[0077] The pressure chamber substrate 54b is a plate-shaped component having a plurality of pressure chambers C, referred to as cavities, provided for each of the first column L1 and the second column L2. The plurality of pressure chambers C are arranged along the Y-axis. Each pressure chamber C is an elongated space formed for each nozzle N and extending along the X-axis when viewed from above. The flow channel substrate 54a and the pressure chamber substrate 54b are manufactured, for example, by processing a single-crystal silicon substrate using semiconductor manufacturing techniques, similar to the aforementioned nozzle plate 54c. However, other known methods and materials may be appropriately used in the respective manufacturing of the flow channel substrate 54a and the pressure chamber substrate 54b.

[0078] The pressure chamber C is a space between the flow passage substrate 54a and the vibration plate 54e. The plurality of pressure chambers C are arranged in the direction along the Y axis for each of the first column Ll and the second column L2. Further, the pressure chamber C communicates with the communication flow passage Na and the supply flow passage Ra, respectively. Therefore, the pressure chamber C communicates with the nozzle N via the communication flow passage Na and with the space Rl via the supply flow passage Ra.

[0079] The vibration plate 54e is arranged on the surface of the pressure chamber substrate 54b facing the Zl direction. The vibration plate 54e is a plate-shaped member capable of elastically vibrating. The vibration plate 54e has, for example, a first layer and a second layer which are laminated in the Zl direction in this order. The first layer is, for example, an elastic film composed of silicon oxide (SiO2). The elastic film is formed, for example, by thermally oxidizing one surface of a single-crystal silicon substrate. The second layer is, for example, an insulating film composed of zirconium oxide (ZrO2). The insulating film is formed, for example, by forming a layer of zirconium by a sputtering method and thermally oxidizing the layer. Note that the vibration plate 54e is not limited to the structure formed by laminating the first layer and the second layer described above, and can be composed of a single layer, for example, or three or more layers.

[0080] On the surface of the vibration plate 54e facing the Zl direction, the plurality of piezoelectric elements 54f corresponding to the nozzles N for each of the first column Ll and the second column L2 are arranged as drive elements. Each piezoelectric element 54f is a passive element which deforms by supply of a drive signal. Each piezoelectric element 54f is in a long strip shape extending in the direction along the X axis when viewed from above. The plurality of piezoelectric elements 54f are arranged in the direction along the Y axis in a manner corresponding to the plurality of pressure chambers C. The piezoelectric elements 54f overlap the pressure chambers C when viewed from above.

[0081] Although not illustrated, each piezoelectric element 54f has a first electrode, a piezoelectric layer, and a second electrode, and they are sequentially laminated in the Zl direction. One of the first electrode and the second electrode is an independent electrode that is configured to be separate from each other for each piezoelectric element 54f, on which a drive signal is applied. The other of the first electrode and the second electrode is a common electrode that is in a band shape extending in the direction along the Y axis in a continuous manner across the plurality of piezoelectric elements 54f, on which a predetermined reference potential is supplied. As a metal material of these electrodes, for example, a metal material such as platinum (Pt), aluminum (Al), nickel (Ni), gold (Au), copper (Cu), or the like can be cited, and one of them can be used alone, or two or more of them can be used in combination in an alloy or a laminate, or the like. The piezoelectric layer is composed of a piezoelectric material such as lead zirconate titanate (Pb(Zr, Ti)O3) or the like, and is, for example, in a band shape extending in the direction along the Y axis in a continuous manner across the plurality of piezoelectric elements 54f. However, the piezoelectric layer can be integrated across the plurality of piezoelectric elements 54f. In this case, in the piezoelectric layer, through-holes that penetrate the piezoelectric layer are provided in a manner extending in the direction along the X axis on regions corresponding to the gaps of each pressure chamber C adjacent to each other when viewed in plan. When the vibration plate 54e vibrates in conjunction with the deformation of the above piezoelectric element 54f, the ink in the pressure chamber C is changed in pressure, and the ink is ejected from the nozzle N. In addition, as a drive element, instead of the piezoelectric element 54f, a heating element that heats the ink in the pressure chamber C can be used.

[0082] The protection plate 54g is a plate-shaped member provided on the surface of the vibration plate 54e facing the Zl direction, and protects the plurality of piezoelectric elements 54f, and reinforces the mechanical strength of the vibration plate 54e. Here, the plurality of piezoelectric elements 54f are housed between the protection plate 54g and the vibration plate 54e. The protection plate 54g is composed of, for example, a resin material.

[0083] The housing 54h is a housing for storing the ink supplied to the plurality of pressure chambers C. The housing 54h is composed of, for example, a resin material. In the housing 54h, a space R2 is provided for each of the first column Ll and the second column L2. The space R2 is a space that communicates with the aforementioned space Rl, and functions as a reservoir R that stores the ink supplied to the plurality of pressure chambers C together with the space Rl. In the housing 54h, an introduction port IO for supplying the ink to each reservoir R is provided. The ink in each reservoir R is supplied to the pressure chamber C via each supply flow path Ra.

[0084] The absorber 54d, also known as a flexible substrate, is a flexible resin film forming the wall of the reservoir R, absorbing pressure fluctuations of the ink within the reservoir R. Alternatively, the absorber 54d can be a flexible sheet of metal. The Z1-facing surface of the absorber 54d is bonded to the flow channel substrate 54a using an adhesive or similar material. On the Z2-facing surface of the absorber 54d, a frame 54k is bonded using an adhesive or similar material. The frame 54k is a frame-shaped component along the outer periphery of the absorber 54d and contacts the aforementioned fixing plate 55. Here, the frame 54k is made of metal materials such as stainless steel, aluminum, titanium, and magnesium alloy. By constructing the frame 54k from a metal material, heat from the heater 56 can be appropriately transferred to the ink within the head chip 54 via the holder 53 and the fixing plate 55. Furthermore, in Figure 6 In the diagram, the heat transfer path H1 from heater 56 to head chip 54 is schematically shown using dashed arrows. Furthermore, although a portion of the transfer path H1 includes a resin-based absorber 54d, which has relatively low thermal conductivity, the absorber 54d is formed as a thin film for flexibility, resulting in a thin thickness and very low thermal resistance. Therefore, the influence of the absorber 54d on heat conduction from frame 54k to flow channel substrate 54a is minimal.

[0085] A wiring board 54i is mounted on the Z1-oriented surface of the vibrating plate 54e and serves as a mounting component for electrically connecting the control unit 20 to the head chip 54. The wiring board 54i is, for example, a flexible wiring board such as COF (Chip On Film), FPC (Flexible Printed Circuit), or FFC (Flexible Flat Cable). In this embodiment, a drive circuit 54j is mounted on the wiring board 54i for supplying drive voltage to each piezoelectric element 54f. The drive circuit 54j is a circuit that switches whether to supply at least a portion of the waveform contained in the drive signal D as a drive pulse based on a control signal S.

[0086] 1-5. Structure of the retainer

[0087] Figure 7 This is a bottom view of the retainer 53 in the first embodiment, viewed in the Z1 direction. Figure 8 This is a top view of the retainer 53 in the first embodiment, viewed in the Z2 direction. (See attached image.) Figure 7 as well as Figure 8 As shown above, the holder 53, which is generally tray-shaped, has a bottom 5a, an outer wall portion 5b, and a flange portion 5c.

[0088] The bottom portion 5a is substantially plate-shaped that expands in a direction orthogonal to the Z-axis, and constitutes a bottom surface of the aforementioned recessed portion 53a. Here, the bottom portion 5a is divided into a holding portion 5al and a connecting portion 5a2 that is disposed so as to surround the outer periphery of the holding portion 5al, and is thinner in thickness than the holding portion 5al.

[0089] The holding portion 5al has the aforementioned four recessed portions 53d, and holds the four head chips 54. Each head chip 54 is housed in a space surrounded by each recessed portion 53d and the fixing plate 55. Further, as shown in Figure 7 the holding portion 5al, in addition to the four recessed portions 53d, two recessed portions 53h are provided. Each recessed portion 53h is a so-called recessed portion for reducing the wall thickness, and is disposed between the four recessed portions 53d, and has a depth that is the same as that of the recessed portion 53d. Such a holding portion 5al has a heat receiving portion 5al l and a side wall portion 5al2.

[0090] The heat receiving portion 5al l is plate-shaped, and has a first face Fl that expands in a direction orthogonal to the Z-axis, and a second face F2, and constitutes a bottom surface of the recessed portion 53d and the recessed portion 53h. The first face Fl is a heat receiving face that faces the Zl direction and receives heat from the heater 56. On the first face Fl, the flow path structure 51 is placed via the aforementioned heater 56 and the heat conducting member 57. The second face F2 faces the Z2 direction, and constitutes a bottom surface of the recessed portion 53d and the recessed portion 53h.

[0091] In the example shown in Figure 7 and Figure 8 the heat receiving portion 5al l, the plurality of ink holes 53b and the plurality of wiring holes 53c are provided so as to open on each of the first face Fl and the second face F2. Further, in the first face Fl of the heat receiving portion 5al l, in addition to these openings, a plurality of holes 53e, a plurality of holes 53f, and a plurality of screw holes 53g are provided.

[0092] The plurality of holes 53e are holes for positioning of the head chip 54 with respect to the holder 53, by insertion of a not-shown protrusion provided on the head chip 54. The plurality of holes 53f are holes for insertion of a positioning pin used in positioning of the flow path structure 51, the heater 56, and the heat conducting member 57. The plurality of screw holes 53g are screw holes used in screw fixing of the heat conducting member 57. The plurality of screw holes 53g are screw holes used in screw fixing of the flow path structure 51.

[0093] The side wall portion 5a12 protrudes from the heated portion 5a11 in the Z2 direction and constitutes the side surface of the recessed portion 53d and the recessed portion 53h. At the end of the side wall portion 5a12 in the Z2 direction, the connecting portion 5a2 is connected. Here, the shape of the side wall portion 5a12 when viewed in the direction along the Z axis is the shape obtained by removing the plurality of recessed portions 53d and the plurality of recessed portions 53h from the shape of the heated portion 5a11. That is, the side wall portion 5a12 includes, when viewed in the direction along the Z axis, the partition wall between the adjacent plurality of recessed portions 53d, the partition wall between the adjacent recessed portion 53d and the recessed portion 53h, and the outer peripheral wall that surrounds the plurality of recessed portions 53d and the plurality of recessed portions 53h.

[0094] The connecting portion 5a2 is configured to surround the holding portion 5a1 when viewed in the direction along the Z axis. The connecting portion 5a2 is in a plate shape that extends from the side wall portion 5a12 in a direction orthogonal to the Z axis and connects the side wall portion 5a12 and the outer wall portion 5b across the entire periphery. In addition, the connecting portion 5a2 can be in a shape having a portion with a defect or can be constituted by a plurality of portions that are arranged side by side with a space in the peripheral direction.

[0095] The outer wall portion 5b is in a frame shape that extends from the periphery of the bottom portion 5a across the entire periphery in the Z1 direction and constitutes the side surface of the aforementioned recessed portion 53a.

[0096] The flange portion 5c is in a plate shape that protrudes from the end of the outer wall portion 5b in the Z1 direction toward the outside and in a direction orthogonal to the Z axis. In this way, on the inner periphery of the flange portion 5c, the outer periphery of the connecting portion 5a2 of the bottom portion 5a is connected via the outer wall portion 5b. In addition, the flange portion 5c is connected to the outer wall portion 5b at the outer periphery of the flange portion 5c. Figure 7 and Figure 8 In the example shown, the flange portion 5c is rectangular or substantially rectangular when viewed from above. Therefore, the outer shape of the holder 53 when viewed from above is rectangular or substantially rectangular. On the flange portion 5c, in addition to the plurality of screw holes 53i and the plurality of screw holes 53k described above, a plurality of holes 53j are provided. The plurality of holes 53j are holes for positioning the holder 53 with respect to the support body 41 by insertion of a protrusion not shown that is provided on the support body 41.

[0097] 1-6. Shape of holding portion of holder

[0098] Figure 9 This is a diagram for explaining the shape of the holding portion 5a1 of the holder 53 in the first embodiment. In Figure 9 , for ease of explanation, the respective outer shapes of the holding portion 5a1 and the plurality of head chips 54 when viewed in the Z2 direction are indicated by solid lines.

[0099] As Figure 9As shown, when viewed from above along the Z-axis, the outer edge OE1 of the holding part 5a1 has a shape corresponding to the arrangement of the head chips 54_1, 54_2, 54_3, and 54_4. That is, when viewed from above, the outer edge OE1 has a shape as if a pair of opposite corners of a rectangle and their surrounding portions were cut into a roughly rectangular shape. Hereinafter, the arrangement of the head chips 54_1, 54_2, 54_3, and 54_4 and the shape of the outer edge OE1 of the holding part 5a1 when viewed from above will be described in detail.

[0100] like Figure 9 As shown, head chips 54_1, 54_2, 54_3, and 54_4 are arranged in an alternating manner when viewed from above. Head chips 54_1 and 54_2 are adjacent to each other, head chips 54_2 and 54_3 are adjacent to each other, and head chips 54_3 and 54_4 are adjacent to each other.

[0101] Specifically, head chips 54_1, 54_2, 54_3, and 54_4 are arranged side-by-side in the X1 direction. However, head chips 54_1 and 54_3 are positioned offset from head chips 54_2 and 54_4 in the Y1 direction. Here, head chips 54_1 and 54_3 are arranged side-by-side in the X-axis direction so that their positions are aligned with each other in the Y-axis direction. Similarly, head chips 54_2 and 54_4 are arranged side-by-side in the X-axis direction so that their positions are aligned with each other in the Y-axis direction. Furthermore, the top view shape of each head chip 54 is a rectangle or approximately a rectangle extending in the Y-axis direction.

[0102] exist Figure 9 In the diagram, when viewed from above, a hypothetical rectangle VS is shown as an external boundary of the assembly of head chips 54_1, 54_2, 54_3, and 54_4, as described above, indicated by a double-dotted line. Rectangle VS is the smallest rectangle containing this assembly when viewed from above. Furthermore, in this embodiment, each of the multiple head chips 54_1, 54_2, 54_3, and 54_4 is connected to the hypothetical rectangle VS. Figure 9 In the example shown, the assembly has a shape that is quadratically symmetrical when viewed from above.

[0103] The outer edge OE1 of the retaining part 5a1 has a portion located inside the rectangle VS and a portion located outside.

[0104] Here, when the four sides of the oblong VS are set as a first side E1, a second side E2, a third side E3, and a fourth side E4, the head chip 54_1 is in contact with the first side E1 and the third side E3 when viewed in plan view. The head chip 54_2 is in contact with the second side E2 when viewed in plan view. The head chip 54_3 is in contact with the third side E3 when viewed in plan view. The head chip 54_4 is in contact with the second side E2 and the fourth side E4 when viewed in plan view.

[0105] Here, the first side E1 is one of the four sides of the oblong VS. The second side E2 is a side of the four sides of the oblong VS that is connected to one end of the first side E1. The third side E3 is a side of the four sides of the oblong VS that is connected to the other end of the first side E1. The fourth side E4 is a side of the four sides of the oblong VS other than the first side E1, the second side E2, and the third side E3.

[0106] The first region RE1 surrounded by the first side E1, the second side E2, the head chip 54_1, and the head chip 54_2 when viewed in plan view is bisected by the outer edge OE1 into a first inner portion RE1a and a first outer portion RE1b. The first inner portion RE1a is a portion of the first region RE1 that is located inwardly compared to the outer edge OE1. The first outer portion RE1b is a portion of the first region RE1 that is located outwardly compared to the outer edge OE1. In addition, the first region RE1 when viewed in plan view is a rectangular-shaped region surrounded by the first side E1, the second side E2, a straight line along the two short sides of the head chip 54_1 that is closer to the head chip 54_2, and a straight line along the two long sides of the head chip 54_2 that is closer to the head chip 54_1.

[0107] Here, the first side E1 has a first portion PA1 that demarcates the first region RE1. The first portion PA1 is a side of the four sides of the oblong first region RE1 that belongs to the first side E1. The second side E2 has a second portion PA2 that demarcates the first region RE1. The second portion PA2 is a side of the four sides of the oblong first region RE1 that belongs to the second side E2. Also, the outer edge OE1 of the holding portion 5a1 intersects both the first portion PA1 and the second portion PA2 when viewed in plan view.

[0108] In addition, the intersection point IPa of the outer edge OE1 of the holding portion 5a1 and the first portion PA1 is located closer to the head chip 54_1 than the midpoint MP1 of the first portion PA1 when viewed in plan view, and the intersection point IPb of the outer edge OE1 of the holding portion 5a1 and the second portion PA2 is located closer to the head chip 54_2 than the midpoint MP2 of the second portion PA2 when viewed in plan view. In addition, in the example shown, the intersection point IPb is located extremely close to the midpoint MP2, but is located in the X1 direction with respect to the midpoint MP2. Figure 9 In the example shown, the intersection point IPb is located extremely close to the midpoint MP2, but is located in the X1 direction with respect to the midpoint MP2.

[0109] Further, the center CP of the first region RE1 is located outside the outer edge OE1 of the holding portion 5a1 when viewed in plan view. That is, the center CP of the first region RE1 is not included inside the outer edge OE1 of the holding portion 5a1. In addition, the first region RE1 is located inside the outer edge OE1 of the holding portion 5a1 when viewed in plan view. Figure 9 In the example shown, although the center CP is located in a position extremely close to the outer edge OE1, it is located outside the outer edge OE1.

[0110] As with the first region RE1 described above, the second region RE2 surrounded by the third edge E3, the fourth edge E4, the head chip 54_3, and the head chip 54_4 is divided into a second inside portion RE2a and a second outside portion RE2b by the outer edge OE1 when viewed in plan view. The second inside portion RE2a is located inside compared to the outer edge OE1. The second outside portion RE2b is located outside compared to the outer edge OE1. In addition, the second region RE2 is a region in a rectangular shape surrounded by the third edge E3, the fourth edge E4, a straight line along the long edge of the two long edges of the head chip 54_3 that is closer to the head chip 54_4, and a straight line along the short edge of the two short edges of the head chip 54_4 that is closer to the head chip 54_3 when viewed in plan view.

[0111] 1-7. Shape of heater

[0112] Figure 10 This is a diagram for describing the shape of the heater 56 and the heat conduction member 57 in the first embodiment. In Figure 10 , the respective outer shapes of the heater 56 and the plurality of head chips 54 as viewed in the Z2 direction are indicated by solid lines for ease of description. In addition, in Figure 10 , the outer shape of the flow passage structure 51 or the heat conduction member 57 as viewed in the Z2 direction is indicated by a dashed line.

[0113] As shown in Figure 10 , the outer edge OE2 of the heater 56 has a shape corresponding to the arrangement of the head chips 54_1, 54_2, 54_3, and 54_4 when viewed in plan view in the direction along the Z axis. In the present embodiment, as shown in the aforementioned Figure 8 , the outer edge OE2 is substantially the same shape as the aforementioned outer edge OE1 of the holding portion 5a1. That is, it can be said that the outer edge OE2 is along the shape of the outer edge OE1. Hereinafter, the plan view shape of the outer edge OE2 of the heater 56 will be described in detail in order.

[0114] In Figure 10 , the aforementioned imaginary rectangle VS is shown by a double-dot chain line. The outer edge OE2 of the heater 56 has a portion inside the rectangle VS and a portion outside, similarly to the aforementioned outer edge OE1 of the holding portion 5a1.

[0115] The first region RE1 is divided into a first inner portion RE1c and a first outer portion RE1d by the outer edge OE2 when viewed in plan. The first inner portion RE1c is a portion of the first region RE1 that is located inwardly relative to the outer edge OE2. The first outer portion RE1d is a portion of the first region RE1 that is located outwardly relative to the outer edge OE2. Also, in the present embodiment, since the outer edge OE2 is substantially the same shape as the outer edge OE1 of the holding portion 5a1 as described above, the first inner portion RE1c is substantially equal to the aforementioned first inner portion RE1a, and the first outer portion RE1d is substantially equal to the first outer portion RE1b.

[0116] Here, the outer edge OE2 of the heater 56 contains the plurality of head chips 54 thereinside when viewed in plan, and intersects both the first portion PA1 and the second portion PA2. Also, the intersection IPc of the outer edge OE2 of the heater 56 and the first portion PA1 is located closer to the head chip 54_1 than the midpoint MP1 of the first portion PA1 when viewed in plan, and the intersection IPd of the outer edge OE2 of the heater 56 and the second portion PA2 is located closer to the head chip 54_2 than the midpoint MP2 of the second portion PA2. Also, in the present embodiment, the intersection IPd is located extremely close to the midpoint MP2, but is located in the X1 direction relative to the midpoint MP2. Figure 10 In the example shown, although the intersection IPd is located extremely close to the midpoint MP2, it is located on the outer side of the outer edge OE2.

[0117] The center CP of the first region RE1 is located on the outer side of the outer edge OE2 when viewed in plan. That is, the center CP of the first region RE1 is not contained on the inner side of the outer edge OE2 of the heater 56. Also, in the present embodiment, although the center CP is located extremely close to the outer edge OE2, it is located on the outer side of the outer edge OE2. Figure 10 In the example shown, although the center CP is located extremely close to the outer edge OE2, it is located on the outer side of the outer edge OE2.

[0118] As with the first region RE1 described above, the second region RE2 is divided into a second inner portion RE2c and a second outer portion RE2d by the outer edge OE2 when viewed in plan. The second inner portion RE2c is located inwardly relative to the outer edge OE2. The second outer portion RE2d is located outwardly relative to the outer edge OE2. Also, in the present embodiment, the second inner portion RE2c is substantially equal to the aforementioned second inner portion RE2a, and the second outer portion RE2d is substantially equal to the second outer portion RE2b.

[0119] In contrast to this, Figure 10The heat-conducting member 57 indicated by a broken line in FIG. 6 overlaps not only the head chip 54_1, 54_2, 54_3, 54_4 but also at least a portion of each of the first outer side portion RE1d and the second outer side portion RE2d in plan view. Also, although not shown, the heat-conducting member 57 overlaps at least a portion of each of the first outer side portion RE1b and the second outer side portion RE2b indicated by the broken line in FIG. 5 in plan view. Figure 9

[0120] Here, the plan view shape of the heat-conducting member 57 is substantially equal to the plan view shape of the flow path structure 51. Therefore, the flow path structure 51 overlaps at least a portion of each of the first outer side portion RE1d and the second outer side portion RE2d in plan view. Also, although not shown, the flow path structure 51 overlaps at least a portion of each of the first outer side portion RE1b and the second outer side portion RE2b indicated by the broken line in FIG. 5 in plan view. Figure 9

[0121] 1-8. Heat transfer path from the heater

[0122] Figure 11 A diagram for explaining the heat transfer path H1 and the heat transfer path H2 from the heater 56 in the first embodiment. In Figure 11 In FIG. 6, each of the heat transfer path H1 and the heat transfer path H2 is schematically shown by a broken line.

[0123] As described above, in the support body 41, the opening 41a into which the outer wall portion 5b is inserted is provided. On the other hand, the flange portion 5c has the mounting surface 5c1 toward the normal direction of the nozzle face FN, that is, the Z2 direction. Also, the holder 53 is mounted on the support body 41 in a state in which the outer wall portion 5b is inserted into the opening 41a with a gap d1 between the outer wall portion 5b and the support body 41 and the mounting surface 5c1 is in contact with the support body 41.

[0124] The heater 56 heats each head chip 54 by transferring heat to each head chip 54 on the heat transfer path H1 as described above.

[0125] However, a portion of the heat from the heater 56 is transferred to the support body 41 via the holder 53. That is, a portion of the heat from the heater 56 is not used for heating of each head chip 54 but escapes to the support body 41 via the holder 53. Such escape of heat not only results in a decrease in the heating efficiency of each head chip 54 by the heater 56 but also becomes a cause of deviation in the temperature distribution within each head chip 54 or among the head chips 54.

[0126] ​​Therefore, in order to reduce the escape of such heat, the holder 53 has a structure that increases the thermal resistance of the heat transferred from the heater 56 to the support body 41 on the transfer path H2. Specifically, in the holder 53, as described above, the heated portion 5al l and the flange portion 5c are connected via the side wall portion 5al2, the connecting portion 5a2, and the outer wall portion 5b.

[0127] The transfer path H2 is a path in which heat is transferred in the order of the heated portion 5al l, the side wall portion 5al2, the connecting portion 5a2, the outer wall portion 5b, and the flange portion 5c. As described above, the side wall portion 5al2 and the outer wall portion 5b each extend in the direction along the Z axis, in contrast to which the connecting portion 5a2 and the flange portion 5c each extend in the direction intersecting the Z axis. Therefore, the transfer path H2 is bent or curved at least at two places between the heated portion 5al l and the flange portion 5c when viewed in the cross section as shown in FIG. 6. Figure 11 Figure 11 In FIG. 6, the two places where the transfer path H2 is bent or curved are shown by the areas enclosed by the double-dot chain lines.

[0128] Here, the outer peripheral surface of the side wall portion 5al2 is configured so as to be spaced apart from the inner peripheral surface of the outer wall portion 5b by a distance d3 across the entire area. Therefore, the transfer of heat from the side wall portion 5al2 to the outer wall portion 5b is not directly performed therebetween, but is performed via the connecting portion 5a2. Further, the flow channel structure 51 is configured so as to be spaced apart from the outer wall portion 5b by a distance d2. Therefore, the transfer of heat from the heated portion 5al l to the outer wall portion 5b is not performed via the flow channel structure 51.

[0129] As described above, the liquid ejection head 50 described above is provided with a plurality of head chips 54, a holder 53 that is thermally conductive, a flow channel structure 51 that is thermally conductive, and a heater 56 that is planar. The plurality of head chips 54 each have a nozzle face FN on which nozzles N that eject ink that is an example of a "liquid" are provided. The holder 53 holds the plurality of head chips 54. In the flow channel structure 51, flow channels through which the ink supplied to the plurality of head chips 54 are provided. The heater 56 is disposed between the holder 53 and the flow channel structure 51, and extends in a direction parallel to the nozzle face FN. On this basis, the heater 56 overlaps the plurality of head chips 54 when viewed in plan view.

[0130] ​In the liquid ejection head 50 described above, the heater 56 is disposed between the retainer 53 and the flow channel structure 51. Therefore, compared with the conventional structure in which the flow channel structure 51 is interposed between the heater 56 and the retainer 53, heat from the heater 56 can be efficiently transferred to the retainer 53 and the flow channel structure 51, respectively. As a result, the temperature difference between the retainer 53 and the flow channel structure 51 can be reduced, and further, the temperature difference between the head chip 54 and the flow channel structure 51 can be reduced. In addition, the heater 56 is in a planar shape along a direction parallel to the nozzle surface, and the heater 56 overlaps the plurality of head chips 54 when viewed in plan view. Therefore, compared with a structure in which the heater 56 overlaps only a part of the plurality of head chips 54 when viewed in plan view, heat from the heater 56 can be efficiently transferred to each of the plurality of head chips 54. As a result, the temperature difference between the plurality of head chips 54 can also be reduced. According to the above, the temperature of the head chip 54 can be managed with high precision by temperature control of the heater 56.

[0131] In the present embodiment, as described above, the retainer 53 has a plurality of head chips 54 held by a holding portion 5al. The holding portion 5al contains the plurality of head chips 54 when viewed in plan view. Therefore, heat from the heater 56 can be transferred to the plurality of head chips 54 via one holding portion 5al. As a result, it is not necessary to provide the heater 56 for each head chip 54, and thus the heater 56 can be easily disposed.

[0132] On this basis, each of the plurality of head chips 54 is elongated along the direction along the Y axis. In addition, the plurality of head chips 54 includes a head chip 54_1 that is an example of a "first head chip", and a head chip 54_2 that is an example of a "second head chip". The head chip 54_1 and the head chip 54_2 are adjacent to each other. Here, the plurality of head chips adjacent to each other means the positional relationship of the plurality of head chips 54 to each other, and a structure other than the head chip 54 (for example, the side wall portion 5a12 corresponding to the holder 53 in the present embodiment) can also be interposed between the plurality of head chips 54. In addition, the head chip 54_1 and the head chip 54_3 are arranged in a manner that the end portion of the Y1 direction of the head chip 54_2 is interposed therebetween, at positions offset from each other in the direction along the X axis and the same in the direction along the Y axis. However, the head chip 54_1 and the head chip 54_3 are in a positional relationship in which they are opposed to each other in the direction along the X axis, in a dimension of more than half the dimension of the head chip 54 in the direction along the Y axis. Therefore, it can be said that these head chip 54_1 and the head chip 54_3 are also in a relationship adjacent to each other. Also, the head chip 54_1 and the head chip 54_2 are arranged in a manner offset from each other in both the direction along the Y axis and the direction along the X axis. In addition, when two directions intersecting each other along the nozzle face FN are taken as a first direction and a second direction, the direction along the Y axis is an example of the "first direction", and the direction along the X axis is an example of the "second direction".

[0133] Here, the head chip 54_1 is in contact with the first edge E1 and the third edge E3 of the imaginary oblong VS when viewed in plan, and the head chip 54_2 is in contact with the second edge E2 when viewed in plan. Also, a first region RE1 surrounded by the first edge E1, the second edge E2, the head chip 54_1, and the head chip 54_2 when viewed in plan includes a first outer side portion RE1b located on the outer side compared to the outer edge OE1 of the holding portion 5a1. In addition, the outer edge OE1 is the outer edge of the side wall portion 5a12 when viewed in plan.

[0134] In addition, as described above, the oblong VS circumscribes the aggregate of the plurality of head chips 54 possessed by the liquid ejection head 50 when viewed in plan. The first edge E1 is one of the four edges of the oblong VS. The second edge E2 is an edge of the four edges of the oblong VS connected to one end of the first edge E1. The third edge E3 is an edge of the four edges of the oblong VS connected to the other end of the first edge E1.

[0135] In the first outer side portion RE1b, neither the holding portion 5a1 nor the head chip 54 is present. Therefore, the presence of the first outer side portion RE1b means that the useless portion of the holding portion 5a1 other than the portion that should be heated is reduced. Therefore, the heat from the heater 56 can be reduced from escaping to the useless portion, as a result of which the head chip 54 can be efficiently heated by the heater 56. Further, there is an advantage that the heater 56 can be reduced in size or reduced in power consumption.

[0136] As described above, in the holder 53, a plurality of ink holes 53b are provided, which constitute flow channels of the ink supplied to the plurality of head chips 54. Therefore, from the viewpoint of improving the resistance of the holder 53 to the ink or efficiently transferring the heat from the heater 56 to the ink in the ink holes 53b via the holder 53, it is preferable that the holder 53 be composed of stainless steel or ceramic.

[0137] Further, the first region RE1 includes a first outer side portion RE1d that does not overlap the heater 56 when viewed in plan. Therefore, the heater 56 can be reduced in size. Since the head chip 54_1 and the head chip 54_2 are not present in the first outer side portion RE1d, the useless heat generation of the heater 56 can be reduced. As a result, the head chip 54 can be efficiently heated by the heater 56.

[0138] Further, as described above, the liquid ejecting head 50 further has the heat conducting member 57 as an example of the "second heat conducting member". The heat conducting member 57 is a member that is disposed between the heater 56 and the flow channel structure 51 and has a higher thermal conductivity than the flow channel structure 51, for example, aluminum. Further, the heat conducting member 57 and the flow channel structure 51 respectively overlap the first outer side portion RE1b when viewed in plan. By the flow channel structure 51 being present in the first outer side portion RE1b, the degree of freedom of the arrangement of the flow channels in the flow channel structure 51 can be improved. Further, since the heat conducting member 57 is disposed between the heater 56 and the flow channel structure 51, the heat from the heater 56 can be transferred to the flow channel structure 51 after being spread in the planar direction by the second heat conducting member. In particular, even in the portion of the first outer side portion RE1b in which the flow channel structure 51 is present, since the heat conducting member 57 is present in the first outer side portion RE1b, the heat from the heater 56 can also be transferred to the portion via the heat conducting member 57. As a result, the deviation of the temperature distribution of the flow channel structure 51 caused by the heater 56 can be reduced.

[0139] Further, as described above, from the viewpoint of improving the resistance of the flow path structure 51 to ink, or efficiently transferring heat from the heater 56 to the ink inside the flow path structure 51, it is preferable that the flow path structure 51 be composed of stainless steel or ceramic.

[0140] Further, in the present embodiment, the plurality of head chips 54 include a head chip 54_3 that is an example of a "third head chip", and a head chip 54_4 that is an example of a "fourth head chip". The head chip 54_3 and the head chip 54_4 are arranged so as to be offset from each other in both the direction along the Y axis and the direction along the X axis.

[0141] Here, when a side other than the first side El, the second side E2, and the third side E3 among the four sides of the imaginary oblong VS is set as a fourth side E4, the head chip 54_3 is in contact with the third side E3 when viewed from above, and the head chip 54_4 is in contact with the second side E2 and the fourth side E4 when viewed from above. Also, a second region RE2 surrounded by the third side E3, the fourth side E4, the head chip 54_3, and the head chip 54_4 when viewed from above includes a second outer side portion RE2b located on the outer side compared to the outer edge OE1 of the holding portion 5al.

[0142] In the second outer side portion RE2b, as with the aforementioned first outer side portion RElb, neither the holding portion 5al nor the head chip 54 is present. Therefore, the presence of the second outer side portion RE2b means that the unnecessary portion of the holding portion 5al other than the portion that should be heated is reduced. Therefore, it is possible to reduce the case where heat from the heater 56 partially escapes into the unnecessary portion, as a result of which it is possible to efficiently heat the head chip 54 by the heater 56. Further, it also has the advantage that miniaturization or power saving of the heater 56 can be achieved.

[0143] The area of the first outer side portion RElb is preferably more than one fourth of the area of the first region REl, and more preferably more than one half and less than nine tenths of the area of the first region REl. When the area of the first outer side portion RElb is within this range, it is possible to preferably reduce the unnecessary portion of the holding portion 5al as described above. On the other hand, when the area of the first outer side portion RElb is too small, there is a tendency for the consumed power of the heater 56 to increase, or for the deviation of the temperature distribution within each head chip 54 or among the plurality of head chips 54 to easily occur. On the other hand, when the area of the first outer side portion RElb is too large, it is difficult to secure the thickness required for the holding portion 5al. In addition, as with the relationship between the area of the first outer side portion RElb and the first region REl, the area of the second outer side portion RE2b is also preferably more than one fourth of the area of the second region RE2.

[0144] Further, as described above, the heater 56 overlaps the plurality of head chips 54 when viewed in plan view. Also, the aforementioned first region RE1 includes a first outer portion RE1d that is located outward of the outer edge OE2 of the heater 56 when viewed in plan view.

[0145] In the first outer portion RE1d, neither the heater 56 nor the head chip 54 is present. Therefore, the presence of such a first outer portion RE1d means that an unnecessary portion of the heater 56 is reduced. Therefore, it is possible to reduce the deviation in the temperature distribution within each head chip 54 or between the plurality of head chips 54 caused by heat generation from the unnecessary portion. Further, it also has the advantage that the heater 56 can be made smaller in area or can be made more power efficient.

[0146] Here, the aforementioned thermally conductive member 57 and the flow passage structure 51 each overlap the first outer portion RE1d when viewed in plan view. By the flow passage structure 51 being present in the first outer portion RE1d, it is possible to improve the degree of freedom in the arrangement of the flow passages within the flow passage structure 51. Further, even in the portion of the first outer portion RE1d in which the flow passage structure 51 is present, since the thermally conductive member 57 is present in the first outer portion RE1d, it is also possible to transmit heat from the heater 56 to this portion via the thermally conductive member 57. As a result, it is possible to reduce the deviation in the temperature distribution of the flow passage structure 51 caused by the heater 56. This structure is particularly useful in which a portion of the flow passages within the flow passage structure 51 overlaps the first outer portion RE1d when viewed in plan view.

[0147] Further, as described above, the aforementioned second region RE2 includes a second outer portion RE2d that is located outward of the outer edge OE2 of the heater 56 when viewed in plan view.

[0148] In the second outer portion RE2d, as with the aforementioned first outer portion RE1d, neither the heater 56 nor the head chip 54 is present. Therefore, the presence of such a second outer portion RE2d means that an unnecessary portion of the heater 56 is reduced. Therefore, it is possible to reduce the deviation in the temperature distribution within each head chip 54 or between the plurality of head chips 54 caused by heat generation from the unnecessary portion. Further, it also has the advantage that the heater 56 can be made smaller in area or can be made more power efficient.

[0149] The area of the first outer portion RE1d is preferably more than one fourth of the area of the first region RE1, and more preferably more than one half and less than nine tenths of the area of the first region RE1. When the area of the first outer portion RE1d is within such a range, the unnecessary portion of the heater 56 can be appropriately reduced. In contrast, when the area of the first outer portion RE1d is too small, there is a tendency that the power consumption of the heater 56 increases, or that the temperature distribution within each head chip 54 or between the plurality of head chips 54 easily deviates. On the other hand, when the area of the first outer portion RE1d is too large, the heat from the heater 56 is difficult to be uniformly transferred to the portion 5a1 depending on the size of the holding portion 5a1 or the like, and even at this point, there is a tendency that the temperature distribution within each head chip 54 or between the plurality of head chips 54 easily deviates. Also, as with the relationship between the area of the first outer portion RE1d and the first region RE1, the area of the second outer portion RE2d is preferably more than one fourth of the area of the second region RE2.

[0150] Further, as described above, the liquid ejecting head 50 is supported on the support body 41. Here, the holder 53 has, in addition to the holding portion 5a1, a flange portion 5c that contacts the support body 41 at a position separated from the holding portion 5a1. The heater 56 heats the holding portion 5a1. The holding portion 5a1 has a heated portion 5a11 that receives heat from the heater 56.

[0151] On this basis, the shortest path of heat transferred in the retainer 53 from the heated portion 5al l to the flange portion 5c in the transfer path H2 is bent or curved at two or more places. Here, the bending or curving refers to a state in which, for example, in the case of being bent or curved between the side wall portion 5al2 and the connecting portion 5a2 as in the present embodiment, the length of the side wall portion 5al2 along the transfer path H2 (in other words, the length of the side wall portion 5al2 in the direction along the Z axis) and the length of the connecting portion 5a2 along the transfer path H2 (in other words, the length of the connecting portion 5a2 in the direction along the Y axis) are each longer than the thickness in the thickness direction (the direction along the Y axis) of the side wall portion 5al2 and longer than the thickness in the thickness direction (the direction along the Z axis) of the connecting portion 5a2. This is the same even on the bending or curving between the connecting portion 5a2 and the outer wall portion 5b, and even in the case of being bent or curved through portions other than these portions. In addition, the "shortest path from the heated portion 5al l to the flange portion 5c" does not include the path of heat moving inside the heated portion 5al l and the flange portion 5c. More specifically, the "shortest path from the heated portion 5al l to the flange portion 5c" is the portion of the shortest path inside the retainer 53 that does not include the path of heat moving inside the heated portion 5al l and the flange portion 5c, from an arbitrary position of the heated portion 5al l to the position of contact of the flange portion 5c with the support body 41. Therefore, compared with a structure in which the shortest path from the heated portion 5al l to the flange portion 5c is straight, or a structure in which the thickness of the connecting portion 5a2 is thickened in such a way that the face of the connecting portion 5a2 facing the Zl direction coincides with the first face Fl, it is possible to increase the thermal resistance of the shortest path. As a result, it is possible to make it difficult for heat from the heater 56 to be dissipated to the support body 41 via the flange portion 5c. As a result, it is possible to efficiently heat the head chip 54 by the heater 56.

[0152] Here, as described above, the heater 56 is disposed at a position opposite the normal direction (Z2 direction) of the nozzle face FN with respect to the holding portion 5al in the Zl direction. Also, the holding portion 5al has a side wall portion 5al2 extending in the normal direction (Z2 direction) from the heated portion 5al l. The heated portion 5al l and the side wall portion 5al2 form a recessed portion 53d that is one example of a "space" that accommodates the head chip 54. Therefore, it is possible to easily assemble the head chip 54, the retainer 53, and the heater 56 in a manner in which they are laminated in this order.

[0153] On this basis, the holder 53 further has an outer wall portion 5b that is connected to the flange portion 5c and that surrounds the side wall portion 5a12 when viewed in the normal line direction, and a connection portion 5a2 that connects the side wall portion 5a12 and the outer wall portion 5b. Also, the connection portion 5a2 extends in a direction that intersects the normal line direction, and the side wall portion 5a12 and the outer wall portion 5b each extend from the connection portion 5a2 in a direction opposite the normal line direction.

[0154] Thus, the holder 53 has a holding portion 5a1 that holds the head chip 54, a flange portion 5c that contacts the support body 41 at a position separate from the holding portion 5a1, an outer wall portion 5b that is connected to the flange portion 5c and that surrounds the holding portion 5a1 when viewed in a normal line direction of the nozzle face FN, and a connection portion 5a2 that connects the holding portion 5a1 and the outer wall portion 5b. Also, the holding portion 5a1 protrudes from the connection portion 5a2 in a direction opposite the normal line direction, and the outer wall portion 5b extends from the connection portion 5a2 toward the flange portion 5c in a direction opposite the normal line direction.

[0155] By configuring the holder 53 in this way, the shortest path in the transfer path H2 from the heat receiving portion 5a11 to the flange portion 5c has a place where the heat transfer direction is bent or curved by the connection of the side wall portion 5a12 and the connection portion 5a2, and a place where the heat transfer direction is bent or curved by the connection of the outer wall portion 5b and the connection portion 5a2. That is, in the shortest path in the transfer path H2 from the heat receiving portion 5a11 to the flange portion 5c, the heat transfer direction in the side wall portion 5a12 and the heat transfer direction in the outer wall portion 5b are in opposite directions to each other.

[0156] Further, as described above, the outer wall portion 5b surrounds the holding portion 5a1 in a manner that is spaced apart from the holding portion 5a1 when viewed in plan view. Thus, it is possible to easily realize the transfer path H2 that is bent or curved at two or more places between the heat receiving portion 5a11 and the flange portion 5c as described above.

[0157] Also, as described above, the flange portion 5c is disposed at a position that is in a direction opposite the normal line direction of the nozzle face FN compared to the heat receiving portion 5a11. Thus, it is possible to realize elongation in the direction of the Z axis of the outer wall portion 5d, and it is possible to improve the thermal resistance of the transfer path H2.

[0158] Further, as described above, the heat receiving portion 5al l has the first face Fl and the second face F2 which face in opposite directions to each other. Here, the first face Fl is a heat receiving face which receives heat from the heater 56. The head chip 54 has a housing 54h in which a flow path of ink is provided. The housing 54h is fixed to the second face F2 and is made of a material having a lower thermal conductivity than the holder 53. In this way, by making the thermal conductivity of the material of the housing 54h lower than the holder 53, heat generation from the ink in the head chip 54 can be reduced. Here, heat from the heat receiving portion 5al l is less likely to be transmitted to the housing 54h, and as a result, is relatively more likely to move along the holder 53 in the direction toward the support body 41. Therefore, in the case where such a housing 54h is used, the case where heat dissipation from the support body 41 is less likely to occur as described above is particularly useful.

[0159] Further, as described above, the flow path structure 51 is arranged at a position in the direction opposite to the normal direction of the nozzle face FN with respect to the holding portion 5al, and the heater 56 is arranged between the holding portion 5al and the flow path structure 51. Further, the flow path structure 51 is arranged in a manner spaced apart from the outer wall portion 5b by a gap. Therefore, direct heat dissipation from the flow path structure 51 to the outer wall portion 5b can be reduced.

[0160] Further, as described above, the outer peripheral surface of the side wall portion 5al2 is arranged in a manner spaced apart from the entire area of the inner peripheral surface of the outer wall portion 5b when viewed in the normal direction of the nozzle face FN. Therefore, direct heat dissipation from the side wall portion 5al2 to the outer wall portion 5b can be reduced.

[0161] Further, as described above, the flange portion 5c surrounds the outer wall portion 5b across the entire circumference when viewed in the normal direction of the nozzle face FN. Therefore, it is possible to prevent smoke generated in association with ejection of ink in the head chip 54 from being blown from the nozzle face FN to the vertically upper side with respect to the support body 41 by the flange portion 5c. On the other hand, although it is possible that heat of the heater 56 is dissipated from the entire circumference of the flange portion 5c surrounding the outer wall portion 5b to the support body 41, since the outer peripheral surface of the side wall portion 5al2 is arranged in a manner spaced apart from the entire area of the inner peripheral surface of the outer wall portion 5b when viewed in the normal direction of the nozzle face FN as described above, direct heat dissipation from the side wall portion 5al2 to the outer wall portion 5b can be reduced.

[0162] 2. Second Embodiment

[0163] Hereinafter, a second embodiment of the present application will be described. For elements having the same function and effect as those of the first embodiment in the following example, the same symbols as those used in the description of the first embodiment are used, and detailed description thereof will be appropriately omitted.

[0164] Figure 12 This is an exploded perspective view of the liquid injection head 50A according to the second embodiment. Except for the different configurations of the heater 56 and the heat-conducting component 57, the liquid injection head 50A is the same as the liquid injection head 50 of the first embodiment described above.

[0165] like Figure 12 As shown, in this embodiment, the side-by-side arrangement of the heater 56 and the heat-conducting component 57 along the Z-axis is the reverse of that in the first embodiment described above. That is, in the liquid injection head 50A, facing the Z2 direction, they are arranged side-by-side in the following order: cover 58, substrate unit 52, flow channel structure 51, heater 56, heat-conducting component 57, holder 53, four head chips 54, and fixing plate 55. The heat-conducting component 57 in this embodiment is an example of the "first heat-conducting component".

[0166] According to the second embodiment described above, the temperature of the head chip 54 can also be managed with the same high precision as the first embodiment described above. Figure 13 In the example shown, the top view shape of the flow channel structure 51, heater 56, and heat-conducting component 57 is the same as that of the first embodiment described above. That is, when viewed from above, the heat-conducting component 57 overlaps with the first outer portion RE1b. Furthermore, when the heater 56 and the flow channel structure 51 overlap with the first outer portion RE1b when viewed from above, heat from the heater 56 can be transferred to the holding portion 5a1 without any waste.

[0167] However, the top-view shape of the heater 56 is not limited to this; for example, it may be the same as the top-view shape of the flow channel structure 51 or the heat-conducting component 57. That is, in top view, the heater 56 and the flow channel structure 51 may overlap with the first outer portion RE1b, respectively. In this case, even if there is no heat-conducting component 57 between the heater 56 and the flow channel structure 51, the deviation in temperature distribution of the flow channel structure 51 can be reduced.

[0168] Furthermore, the top-view shape of the heat-conducting component 57 can be substantially the same as that of the heater 56. That is, when viewed from above, the heat-conducting component 57 can also be almost non-overlapping with the first outer portion RE1b. Here, "almost non-overlapping" means that more than half of the area of ​​the first outer portion RE1b in the first region RE1, which is located on the outer side of the outer edge of the heat-conducting component 57, does not overlap with the area of ​​the first outer portion RE1b. More preferably, "almost non-overlapping" means that more than three-quarters of the area of ​​the first outer portion RE1b in the first region RE1, which is located on the outer side of the outer edge of the heat-conducting component 57, does not overlap with the area of ​​the first outer portion RE1b.

[0169] Since the heat conductive member 57 is interposed between the heater 56 and the holder 53, the heater 56 is easily moved by the heat conductive member 57 in a direction parallel to the nozzle face FN, and the deviation of the temperature distribution of the holding portion 5al can be reduced.

[0170] 3. Third Embodiment

[0171] Hereinafter, a third embodiment of the present application will be described. In the following exemplary manner, elements having the same function and action as those of the first embodiment are designated by the same symbols as used in the description of the first embodiment, and detailed description thereof will be appropriately omitted.

[0172] Figure 13 A diagram for explaining the heat transfer path Hl and the heat transfer path H2 of the heat from the heater 56 in the third embodiment. The liquid ejection head 50B of the present embodiment is the same as the liquid ejection head 50 of the aforementioned first embodiment except that the holder 53B is provided instead of the holder 53. The holder 53B is the same as the holder 53 except that the outer wall portion 5d is provided instead of the outer wall portion 5b.

[0173] The outer wall portion 5d connects the outer periphery of the connecting portion 5a2 of the bottom portion 5a and the inner periphery of the flange portion 5c. Here, the outer wall portion 5d has a first wall portion 5dl, a first plate portion 5d2, a second wall portion 5d3, a second plate portion 5d4, and a third wall portion 5d5.

[0174] The first wall portion 5dl is in a cylindrical shape extending in the Zl direction from the connecting portion 5a2. The first plate portion 5d2 is in a plate shape extending in a direction orthogonal to the Z axis from the first wall portion 5dl in a manner approaching the holding portion 5al. The second wall portion 5d3 is in a cylindrical shape extending in the Zl direction from the first plate portion 5d2. The second plate portion 5d4 is in a plate shape extending in a direction orthogonal to the Z axis from the second wall portion 5d3 in a manner away from the holding portion 5al. The third wall portion 5d5 is in a cylindrical shape extending in the Zl direction from the second plate portion 5d4.

[0175] Even according to the above third embodiment, the temperature of the head chip 54 can be managed with high precision as in the aforementioned first embodiment. In the present embodiment, since the bottom portion 5a and the flange portion 5c are connected via the outer wall portion 5d as described above, the heat transfer path H2 from the heater 56 to the support body 41 is bent or curved at least at six places. In the present embodiment, the heat transfer path H2 is bent or curved at the connecting portion 5a2, the first wall portion 5dl, the first plate portion 5d2, the second wall portion 5d3, the second plate portion 5d4, and the third wall portion 5d5. Figure 13In the present embodiment, six places of the bending or the curvature of the transfer path H2 are shown by the area surrounded by the double-dot chain line. When the number of the bending or the curvature of the transfer path H2 is four or more, it has an advantage that the thermal resistance of the transfer path H2 is easily increased compared to the first embodiment. Also, as in the first embodiment, the "shortest path from the heated portion 5al l to the flange portion 5c" does not include the path of the heat moving inside the heated portion 5al l and the flange portion 5c.

[0176] 4. Modification

[0177] The above-described modes can be variously modified. Hereinafter, specific modification modes that can be applied to the above-described modes will be exemplified. Two or more modes selected arbitrarily from the following exemplifications can be appropriately combined within a range not contradicting each other.

[0178] 4-1. Modification 1

[0179] In the above-described mode, the plan view shape of the holding portion 5al is a shape different from a rectangle according to the arrangement of the four head chips 54. The plan view shape of the holding portion 5al is not limited to the above-described mode, and can be, for example, a rectangle or a substantially rectangular shape.

[0180] 4-2. Modification 2

[0181] In the above-described mode, the plan view shape of the heater 56 is a shape different from a rectangle according to the arrangement of the four head chips 54. The plan view shape of the heater 56 is not limited to the above-described mode, and can be, for example, a rectangle or a substantially rectangular shape. Further, although the heater 56 is arranged between the flow passage structure 51 and the holder 53 in the above-described mode, it is not limited thereto, and the flow passage structure 51 can be interposed between the heater 56 and the holder 53. Also, the arrangement posture of the heater 56 is not limited to the posture along the nozzle face FN, and can be, for example, perpendicular or inclined with respect to the nozzle face FN. Further, the heater 56 is not limited to a planar shape, and can be, for example, a block shape.

[0182] 4-3. Modification 3

[0183] Although the structure using one heat conduction member 57 is exemplified in the above-described mode, it is not limited to this structure, and can be, for example, a mode obtained by combining the first embodiment and the second embodiment. That is, the heat conduction member 57 can be arranged between the heater 56 and the holder 53, and between the heater 56 and the flow passage structure 51, respectively.

[0184] 4-4. Modification 4

[0185] An elastic sheet can also be provided between the holder 53, which is a rigid body, and the flow channel structure 51. As such an elastic sheet, an elastomer or the like can be used, and, for example, a thermally conductive sheet having a higher thermal conductivity than the resin material that constitutes the housing 54h of the head chip 54 is preferably used. As such an elastic thermally conductive sheet having a higher thermal conductivity than the resin material, a material having a thermal conductivity of 1.0 W / m-K or more is preferably used. Specifically, as the thermally conductive sheet, a sheet of an acrylic or silicone type, or a material in which a metal material such as silicon, stainless steel, aluminum, titanium, and magnesium alloy is dispersed in an elastomer, a composite material in which an elastomer or the like is mixed with a filler such as carbon fiber or ceramic oxide such as silica or alumina, or ceramic nitride such as silicon nitride or boron nitride, or the like is preferably used. By thus filling the gap between the holder 53 and the flow channel structure 51 with an elastic material, even if a manufacturing error occurs in the thickness dimension of the holder 53 or the flow channel structure 51 in the direction along the Z axis, the adhesion between the thermally conductive member 57 or the heater 56 and the heating target object such as the holder 53 or the flow channel structure 51 can be improved, and thus the heat from the heater 56 can be efficiently transferred to the heating target object.

[0186] 4-5. Modified example 5

[0187] The "outer edge OE2 of the heater 56" in the foregoing embodiment can also be referred to as the outer edge of the region in which the heat-generating resistor of the heater 56 is formed.

[0188] 4-6. Modified example 6

[0189] The heater 56 can also not overlap the first outer side portion RE1b when viewed in plan view. In this structure, the area of the heater 56 can be reduced. Further, since the head chip 54_1, the head chip 54_2, and the holding portion 5a1 are not present in the first outer side portion RE1b, the useless heat generation of the heater 56 can be further reduced by the heater 56 not overlapping the first outer side portion RE1b when viewed in plan view.

[0190] 4-7. Modified example 7

[0191] Although the number of head chips 54 included in the liquid ejecting head 50 is four in the foregoing embodiment, the number is not limited to this, and can be three or less or five or more. Further, although the plurality of head chips 54 are arranged in a staggered manner in the long direction of the head chip 54 in the foregoing embodiment, the plurality of head chips 54 can also be arranged in a staggered manner in the short direction of the head chip 54.

[0192] 4-8. Modified example 8

[0193] While the serial type liquid ejecting apparatus 100 in which the support body 41 supporting the liquid ejecting head 50 is reciprocated is exemplified in the foregoing manner, the present application can also be applied to a line type liquid ejecting apparatus in which a plurality of nozzles N are distributed across the entire width of the medium M. That is, the support body supporting the liquid ejecting head 50 is not limited to the carriage of the serial type, and can also be a structure body supporting the liquid ejecting head 50 in a line type. In this case, for example, a plurality of liquid ejecting heads 50 are arranged side by side in the width direction of the medium M, and the plurality of liquid ejecting heads 50 are collectively supported on one support body.

[0194] 4-9. Modified example 9

[0195] The liquid ejecting apparatus exemplified by the foregoing manner can be employed not only in a device dedicated to printing, but also in various devices such as a facsimile apparatus or a copying machine. Of course, the use of the liquid ejecting apparatus is not limited to printing. For example, a liquid ejecting apparatus ejecting a solution of a color material is utilized as a manufacturing apparatus of a color filter of a display apparatus such as a liquid crystal display panel. Further, a liquid ejecting apparatus ejecting a solution of a conductive material is utilized as a manufacturing apparatus of a wiring or an electrode of a wiring substrate. Further, a liquid ejecting apparatus ejecting a solution of an organism-related organic substance is utilized as a manufacturing apparatus of a biochip, for example.

[0196] Explanation of symbols

[0197] 5a…bottom; 5a1…holding portion; 5a11…heat receiving portion; 5a12…side wall portion; 5a2…connecting portion; 5b…outer wall portion; 5c…flange portion; 5c1…mounting surface; 5d…outer wall portion; 5d1…first wall portion; 5d2…first plate portion; 5d3…second wall portion; 5d4…second plate portion; 5d5…third wall portion; 10…liquid reservoir; 20…control unit; 30…transport mechanism; 40…moving mechanism; 41…support body; 41a…opening; 41b…threaded hole; 42…transport belt; 50…liquid ejecting head; 50A…liquid ejecting head; 50B…liquid ejecting head; 51…flow passage structure; 51a…flow passage member; 51b…connecting pipe; 51c…wiring hole; 52…substrate unit; 52a…circuit substrate; 52b…connector; 52c…support plate; 53…holder; 53B…holder; 53a…recess; 53b…ink hole; 53c…wiring hole; 53d…recess; 53e…hole; 53f…hole; 53g…threaded hole; 53h…recess; 53i…threaded hole; 53j…hole; 53k…threaded hole; 53l…flow passage pipe; 54…head chip; 54_1…head chip (first head chip); 54_2…head chip (second head chip); 54_3…head chip (third head chip); 54_4…head chip (fourth head chip); 54a…flow passage substrate; 54b…pressure chamber substrate; 54c…nozzle plate; 54d…vibration absorbing body; 54e…vibration plate; 54f…piezoelectric element; 54g…protective plate; 54h…housing; 54i…wiring substrate; 54j…driving circuit; 54k…frame; 55…fixing plate; 55a…opening portion; 56…heater; 56a…hole; 56b…hole; 57…heat conductive member; 57a…hole; 57b…wiring hole; 57c…hole; 58…cover; 58a…through hole; 58b…opening portion; 100…liquid ejecting apparatus; C…pressure chamber; CP…center; D…drive signal; DM…transport direction; E1…first edge; E2…second edge; E3…third edge; E4…fourth edge; F1…first face; F2…second face; FN…nozzle face; H1…transfer path; H2…transfer path (shortest path); IO…inlet; IPa…intersection; IPb…intersection; IPc…intersection; IPd…intersection; L1…first column; L2…second column; M…medium; MP1…midpoint; MP2…midpoint; N…nozzle; Na…communicating flow passage; OE1…outer edge; OE2…outer edge; PA1…first part; PA2…second part; R…reservoir; R1…space; R2…space; RE1…first region; RE1a…first inner part; RE1b…first outer part; RE1c…first inner part; RE1d…first outer part; RE2…second region; RE2a…second inner part; RE2b…second outer part; RE2c…second inner part; RE2d…second outer part; Ra…supply flow passage; S…control signal; VS…oblong rectangle.

Claims

1. A liquid injection head, characterized in that, The liquid injection head is supported on a support body and has the following features: The first chip, which sprays liquid; A retainer having a retaining portion and a flange portion, the retaining portion holding the first head chip, and the flange portion contacting the support body at a position separate from the retaining portion; A heater that heats the holding part. The heater and the support are arranged at intervals between each other. The holding part has a heating part that receives heat from the heater. The heated portion is disposed between the first head chip and the heater. The shortest path of heat transfer in the retainer from the heated portion to the flange portion bends or curves in more than two places.

2. The liquid injection head as described in claim 1, characterized in that, In the shortest path of heat transfer in the retainer from the heated portion to the flange portion, the direction of heat transfer in a portion of the retainer and the direction of heat transfer in a portion of the retainer different from the heated portion are opposite to each other.

3. The liquid injection head as described in claim 1, characterized in that, The first chip head has a nozzle surface, and the nozzle surface is provided with a nozzle that sprays liquid in a spray direction. When viewed in the jetting direction, the flange is positioned on the outside of the heated portion.

4. The liquid injection head as described in claim 1, characterized in that, The heater is disposed inside the liquid jet head.

5. The liquid injection head as described in claim 1, characterized in that, The holding part holds the first chip head while also holding the second chip head that is spraying liquid. The heated portion is disposed between the first head chip and the second head chip, and the heater.

6. A liquid injection head, characterized in that, The liquid injection head is supported on a support body and has the following features: The first chip, which sprays liquid; A retainer having a retaining portion and a flange portion, the retaining portion holding the first head chip, and the flange portion contacting the support body at a position separate from the retaining portion; A heater that heats the holding part. The heater and the support are arranged at intervals between each other. The holding part has a heating part that receives heat from the heater. The shortest path for heat transfer in the retainer from the heated portion to the flange portion bends or deflects at more than two points. The first chip head has a nozzle surface, and the nozzle surface is provided with a nozzle that sprays liquid in a spray direction. The heater is positioned relative to the retaining part at a location opposite to the jetting direction. The retaining part further includes a sidewall portion that extends from the heated part toward the spraying direction. The heated portion and the sidewall portion form a space for storing the first chip. The retainer has an outer wall portion and a connecting portion. The outer wall portion is connected to the flange portion and surrounds the side wall portion when viewed in the jet direction. The connecting portion connects the side wall portion and the outer wall portion. The connecting portion extends in a direction intersecting the spray direction. The sidewall portion and the outer wall portion extend from the connecting portion in a direction opposite to the spray direction, respectively.

7. The liquid injection head as described in claim 6, characterized in that, The flange portion is positioned in a direction opposite to the jetting direction compared to the heated portion.

8. The liquid injection head as described in claim 6 or 7, characterized in that, The heated portion has a first surface and a second surface that face opposite directions to each other. The first surface is the heated surface that receives heat from the heater. The first chip has a housing with channels for liquid flow. The outer casing is fixed to the second surface and is made of a material with a lower thermal conductivity than the retainer.

9. The liquid injection head as described in claim 6, characterized in that, It also includes a flow channel structure, which is positioned relative to the holding part in a direction opposite to the jetting direction, and is provided with a flow channel for supplying liquid to the first head chip. The heater is disposed between the retaining portion and the flow channel structure. The flow channel structure is arranged at intervals from the outer wall portion.

10. The liquid injection head as claimed in claim 6, characterized in that, When viewed in the jetting direction, the outer peripheral surface of the sidewall is arranged in a way that it spans the entire area relative to the inner peripheral surface of the outer wall.

11. The liquid injection head as claimed in claim 10, characterized in that, The flange portion, when viewed in the jetting direction, spans and surrounds the entire circumference of the outer wall portion.

12. The liquid injection head as claimed in claim 6, characterized in that, It also has a second chip for spraying liquid. The holding section also holds the second head chip.

13. The liquid injection head as described in claim 12, characterized in that, It also features a third and a fourth chip that spray liquid and are adjacent to each other. The first head chip and the second head chip are adjacent to each other. When two directions that intersect each other along the nozzle surface are designated as the first direction and the second direction. The first head chip and the second head chip are configured to be offset from each other in the first direction and the second direction, respectively. The third head chip and the fourth head chip are configured to be offset from each other in both the first direction and the second direction. When viewed in the first direction, if one of the four sides of an imaginary rectangle externally inscribed in the body of the first head chip, the second head chip, the third head chip, and the fourth head chip is designated as the first side, the side connected to one end of the first side is designated as the second side, the side connected to the other end of the first side is designated as the third side, and the side other than the first side, the second side, and the third side is designated as the fourth side, then... When viewed in the first direction, the first head chip is in contact with both the first side and the third side. When viewed from the first direction, the second head chip is in contact with the second side. The third chip is connected to the third side when viewed from the first direction. When viewed in the first direction, the fourth chip is in contact with both the second side and the fourth side. When viewed in the first direction, the first region surrounded by the first side, the second side, the first head chip, and the second head chip, and the second region surrounded by the third side, the fourth side, the third head chip, and the fourth head chip, respectively, include portions located on the outer side compared to the outer edge of the sidewall portion.

14. The liquid injection head as claimed in claim 6, characterized in that, The support body has an opening for insertion of the outer wall portion. The flange portion has a mounting surface facing the jetting direction. The retainer is mounted on the support body such that the outer wall portion is inserted into the opening at a distance from the support body and the mounting surface is in contact with the support body.

15. A liquid injection head, characterized in that, The liquid injection head is supported on a support body and has the following features: The first chip, which sprays liquid; A retainer having a retaining portion and a flange portion, the retaining portion holding the first head chip, and the flange portion contacting the support body at a position separate from the retaining portion; A heater that heats the holding part. The heater and the support are arranged at intervals between each other. The holding part has a heating part that receives heat from the heater. The shortest path for heat transfer in the retainer from the heated portion to the flange portion bends or deflects at more than two points. The shortest path has four or more bends or curves.

16. A liquid injection head, characterized in that, The liquid injection head is supported on a support body and has the following features: The first chip, which sprays liquid; A retainer having a retaining portion and a flange portion, the retaining portion holding the first head chip, and the flange portion contacting the support body at a position separate from the retaining portion; A heater that heats the holding part. The heater and the support are arranged at intervals between each other. The holding part has a heating part that receives heat from the heater. The shortest path for heat transfer in the retainer from the heated portion to the flange portion bends or deflects at more than two points. The retainer has an upper surface and a lower surface facing opposite directions, the lower surface being directly opposite the first head chip. The heater is disposed on the upper surface of the retainer. The heated portion is disposed between the first head chip and the heater. The flange protrudes outward toward the support body.

17. A liquid injection device, characterized in that, have: The liquid injection head according to any one of claims 1 to 16; A support body that supports the liquid injection head.

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