Liquid ejection device, and liquid ejection head

Abstract

The present invention provides a liquid ejection device and a liquid ejection head that can heat the liquid inside each of a plurality of head chips from the outside of the liquid ejection head even when a cage formed of resin is provided. The liquid ejection device includes: a liquid ejection head having a plurality of head chips, a cage, a cage cover, and a fixing plate, wherein each head chip has a nozzle plate having nozzles for ejecting liquid, the cage holds the plurality of head chips and has flow paths for supplying liquid to each of the plurality of head chips and is formed of resin, the cage cover houses the plurality of head chips and the cage and is formed of a material having a higher thermal conductivity than the cage, the fixing plate has the cage cover and the plurality of head chips fixed thereto and the fixing plate is formed of metal; a carriage that mounts the liquid ejection head; and a heating unit that is mounted on the carriage and heats the liquid inside each of the plurality of head chips via the cage cover and the fixing plate.

Description

Technical Field

[0001] The present invention relates to a liquid ejection device and a liquid ejection head. Background Art

[0002] Conventionally, there has been known a liquid ejection device having a liquid ejection head that ejects a liquid such as ink, typified by an inkjet printer. For example, in Patent Document 1, there is disclosed a liquid ejection device having a holder that holds a plurality of head chips and forms a flow path for supplying a liquid to the plurality of head chips. The holder of the liquid ejection device is formed of resin. Further, in Patent Document 2, there is disclosed a liquid ejection head having a heating unit that heats the liquid inside each of the plurality of head chips.

[0003] In the liquid ejection device described in Patent Document 1 above, there is a case where the liquid inside each of the plurality of head chips is heated as described in Patent Document 2. However, in the liquid ejection device described in Patent Document 1, since the plurality of head chips are generally held by a holder formed of a resin having a low thermal conductivity, it is difficult to heat the liquid inside each of the plurality of head chips from the outside of the liquid ejection head.

[0004] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2019-89310

[0005] Patent Document 2: Japanese Unexamined Patent Application Publication No. 2010-214743 Summary of the Invention

[0006] In order to solve the above problems, one aspect of a liquid ejection device according to a preferred aspect of the present invention includes: a liquid ejection head having a plurality of head chips, a holder, a holder cover, and a fixing plate, wherein the head chip has a nozzle plate having a nozzle for ejecting a liquid, the holder holds the plurality of head chips and has a flow path for supplying a liquid to each of the plurality of head chips, and the holder is formed of resin, the holder cover houses the plurality of head chips and the holder, and the holder cover is formed of a material having a higher thermal conductivity than the holder, the fixing plate has the holder cover and the plurality of head chips fixed thereto, and the fixing plate is formed of metal; a carriage on which the liquid ejection head is mounted; and a heating unit mounted on the carriage and heating the liquid inside each of the plurality of head chips via the holder cover and the fixing plate.

[0007] In order to solve the above problems, one embodiment of the liquid ejection head according to a preferred embodiment of the present invention is a liquid ejection head mounted on a carriage equipped with a heating unit, the liquid ejection head having: a plurality of head chips, each of the head chips having a nozzle plate, the nozzle plate having nozzles for ejecting liquid; a holder that holds the plurality of head chips and has flow channels for supplying liquid to each of the plurality of head chips, and the holder is formed of resin; a holder cover that houses the plurality of head chips and the holder, and the holder cover is formed of a material having a higher thermal conductivity than the holder; a fixing plate on which the holder cover and the plurality of head chips are fixed, and the fixing plate is formed of metal, and the liquid inside each of the plurality of head chips is heated by the heating unit and via the holder cover and the fixing plate. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 FIG. is a partial structural diagram of a liquid ejection device 10 according to a first embodiment of the present invention.

[0009] Figure 2 FIG. is an external perspective view of the liquid ejection head 20.

[0010] Figure 3 FIG. is an exploded perspective view of the liquid ejection head 20.

[0011] Figure 4 FIG. is a cross-sectional view of an arbitrary head chip 70.

[0012] Figure 5 FIG. is a Figure 2 sectional view taken along line a-a of the liquid ejection head 20 shown.

[0013] Figure 6 FIG. is a Figure 2 sectional view taken along line b-b of the liquid ejection head 20 shown.

[0014] Figure 7 FIG. is a bottom view of the liquid ejection head 20.

[0015] Figure 8 FIG. is an external perspective view of the carriage 18.

[0016] Figure 9 FIG. is an external perspective view showing the state in which the liquid ejection head 20 is mounted on the carriage 18.

[0017] Figure 10 FIG. is an exploded perspective view of the case where the liquid ejection head 20 is mounted on the carriage 18.

[0018] Figure 11 FIG. is a Figure 9 sectional view taken along line c-c of the state in which the liquid ejection head 20 shown is mounted on the carriage 18.

[0019] Figure 12 This is a cross-sectional view of the carriage 18A in the third modified example. Detailed implementation manners

[0020] Hereinafter, the manners for implementing the present invention will be described with reference to the drawings. However, in each of the drawings, the dimensions and scales of each part are appropriately different from the actual situation. In addition, since the implementation manners described below are preferred specific examples of the present invention, various preferred limitations are imposed technically. However, for the scope of the present invention, as long as there is no description to specifically limit the present invention in the following description, it is not limited to these manners.

[0021] 1. First implementation manner

[0022] Figure 1 This is a partial structural diagram of the liquid ejection device 10 according to the first implementation manner of the present invention. The liquid ejection device 10 of the first implementation manner is an inkjet printing device that ejects ink, which is an example of a liquid, onto a medium 11 such as printing paper. Figure 1 The illustrated liquid ejection device 10 includes a control device 12, a conveyance mechanism 14, a carriage 18, and a liquid ejection head 20. The control device 12 uniformly controls each element of the liquid ejection device 10.

[0023] Under the control implemented by the control device 12, the conveyance mechanism 14 conveys the medium 11 along the +Y direction, which is the sub-scanning direction. Under the control implemented by the control device 12, the carriage 18 reciprocates in the +X direction and the -X direction, which are the main scanning directions. The ink is ejected onto the medium 11 by the liquid ejection head 20 in parallel with the conveyance of the medium 11 and the reciprocation of the carriage 18, thereby forming a desired image on the surface of the medium 11. Further, the ejection direction of the ink ejected by the liquid ejection head 20 is marked as the +Z direction. Hereinafter, the +X direction and the -X direction are collectively referred to as the "X-axis direction", hereinafter, the +Y direction and the -Y direction, which is the opposite direction of the +Y direction, are collectively referred to as the "Y-axis direction", and the +Z direction and the -Z direction, which is the opposite direction of the +Z direction, are collectively referred to as the "Z-axis direction".

[0024] The carriage 18 mounts the liquid ejection head 20 on the surface in the -Z direction. Further, a liquid storage section 17 is provided in the -Z direction of the liquid ejection head 20, and the liquid storage section 17 stores a plurality of liquid containers C1 to C4 that respectively store a plurality of types of inks. The ink in the present embodiment is, for example, UV ink. UV is an abbreviation for Ultra Violet (ultraviolet). UV ink has the property of having a high viscosity at low temperatures and a low viscosity at high temperatures. In order to improve the ejection performance, it is necessary to use UV ink in a high-temperature state. However, the ink in the present embodiment is not limited to UV ink, and may also be water-based ink or organic solvent-based ink used in general printing applications. The ink is, for example, a liquid of a total of four colors: blue-green, magenta, yellow, and black. In the liquid containers C1 to C4 of the present embodiment, blue-green, magenta, yellow, and black inks are respectively stored. In addition, the structure or number of the liquid containers C1 to C4 is not limited to the illustrated case.

[0025] The liquid ejection head 20 includes a plurality of head chips 70. Each head chip 70 is a flow path structure body including a member in which a flow path is formed inside. In the present embodiment, a case where four head chips 70 are arranged side by side along the X-axis direction is illustrated. In each of the head chips 70, two nozzle arrays are respectively arranged. Each of the plurality of head chips 70 extends in the Y-axis direction, and each nozzle array is a set of a plurality of nozzles N arranged linearly along the Y-axis direction. In addition, the number or arrangement of the head chips 70 or the nozzle arrays is not limited to the illustrated case. The liquid ejection head 20 includes a flow path through which the ink flows and a filter that filters the ink flowing through the flow path.

[0026] As Figure 1 illustrated, in the liquid ejection head 20, a drive signal Com for driving the liquid ejection head 20 and a control signal SI for controlling the liquid ejection head 20 are supplied from the control device 12. And, the liquid ejection head 20 is driven by the drive signal Com under the control implemented by the control signal SI, and ejects ink in the +Z direction from a part or all of the plurality of nozzles N provided on the liquid ejection head 20.

[0027] 1.1. Structure of the liquid ejection head 20

[0028] Use Figures 2 to 7 to illustrate the structure of the liquid ejection head 20.

[0029] Figure 2 is a perspective view of the appearance of the liquid ejection head 20. Figure 3 is an exploded perspective view of the liquid ejection head 20. Figure 4 is a cross-sectional view of an arbitrary head chip 70. However, inFigure 4 In addition to the head chip 70, a fixing plate 29 is also shown. Figure 5 Namely, Figure 2 A-a cross-sectional view of the liquid ejection head 20 shown. Figure 6 Namely, Figure 2 B-b cross-sectional view of the liquid ejection head 20 shown. The a-a cross-section and the b-b cross-section are cross-sections parallel to the XZ plane. However, in order to prevent complication of the drawings, the illustration within Figure 5 and Figure 6 the head chip 70 is omitted. Figure 7 Namely, a bottom view of the liquid ejection head 20.

[0030] As Figure 2 and Figure 3 shown, the liquid ejection head 20 in the present embodiment includes a flow path unit 202 and a head main body 204. In the head main body 204, the four head chips 70 described above are accommodated. The flow path unit 202 supplies cyan, magenta, yellow, and black to the respective head chips 70 of the head main body 204 as inks from the liquid containers C1 to C4.

[0031] As Figure 4 shown, the head chip 70 has: a flow path forming substrate 71, a pressure chamber forming substrate 72 laminated on the -Z direction surface of the flow path forming substrate 71, a diaphragm 73 laminated on the -Z direction of the pressure chamber forming substrate 72, a nozzle plate 74 disposed on the +Z direction surface of the flow path forming substrate 71, and a plastic part 75. Nozzles N are formed on the nozzle plate 74. In addition, since structures corresponding to each column of the nozzles N are formed substantially line-symmetrically on one head chip 70, hereinafter, for the sake of convenience of explanation, the structure of the head chip 70 will be described focusing on one column of the nozzles N.

[0032] The flow path forming substrate 71 is a flat plate-like member constituting the ink flow path. In the flow path forming substrate 71 of the present embodiment, openings 712, supply flow paths 714, and communication flow paths 716 are formed. The supply flow paths 714 and the communication flow paths 716 are formed for each nozzle N, and the openings 712 are continuous so as to straddle a plurality of nozzles N. The pressure chamber forming substrate 72 is a flat plate-like member formed with a plurality of openings 722 corresponding to different nozzles N. The flow path forming substrate 71 or the pressure chamber forming substrate 72 is formed of, for example, a single crystal silicon substrate.

[0033] The plastic part 75 is a mechanism for suppressing pressure fluctuations in the flow channels of the head chip 70, and is configured to include a sealing plate 752 and a support body 754. The sealing plate 752 is a flexible film-like resin component, and the support body 754 fixes the sealing plate 752 to the flow channel forming substrate 71 so as to block the openings 712 of the flow channel forming substrate 71 and the respective supply flow channels 714. The support body 754 is formed of a metal such as stainless steel.

[0034] The diaphragm 73 is a flat plate-like component that can vibrate elastically, and is formed, for example, by laminating an elastic film made of an elastic material such as silicon oxide and an insulating film made of an insulating material such as zirconium oxide. The diaphragm 73 and the flow channel forming substrate 71 face each other at intervals inside the respective openings 722 formed in the pressure chamber forming substrate 72. The space clamped by the flow channel forming substrate 71 and the diaphragm 73 inside the respective openings 722 functions as a pressure chamber C for applying pressure to the ink. In the present embodiment, two columns of a plurality of pressure chambers C arranged along the Y-axis direction are arranged along the X-axis direction.

[0035] As Figure 4 As shown, a support body 77 is fixed on the flow channel forming substrate 71 and the protection plate 76. The support body 77 is integrally formed, for example, by molding a resin material. The support body 77 of the present embodiment is a component formed with a space 772 that forms a liquid reservoir R together with the opening 712 of the flow channel forming substrate 71 and a supply port 774 communicating with the liquid reservoir R. In the liquid reservoir R, the ink introduced from the supply port 774 is stored. The ink stored in the liquid reservoir R is distributed and filled into the respective pressure chambers C through the plurality of supply flow channels 714, and is ejected in the +Z direction from the respective pressure chambers C through the communication flow channels 716 and the nozzles N.

[0036] The end of a wiring component 78 is joined to the diaphragm 73. The wiring component 78 is a wiring substrate formed with wirings for transmitting a drive signal Com and a power supply voltage to the respective piezoelectric elements 732. One wiring component 78 is connected to each of the four head chips 70. The wiring component 78 is preferably a flexible wiring substrate such as an FPC, a COF, or an FFC. Here, FPC is an abbreviation for Flexible Printed Circuit. COF is an abbreviation for Chip on Film. FFC is an abbreviation for Flexible Flat Cable.

[0037] As Figure 3 And Figure 6As shown, the wiring component 78 has a drive circuit 781. Additionally, with respect to Figure 3 two of the four head chips 70 shown in Figure 3 , drive circuits 781 are provided on the -X direction surface of the wiring component 78. For the remaining two head chips 70, drive circuits 781 are provided on the +X direction surface of the wiring component 78. In

[0038] As Figure 2 and Figure 3 shown, the flow channel unit 202 is formed in such a way that each structural component is housed within a component formed by the housing 22 and the cage cover 23. The housing 22 is formed, for example, by injection molding of a resin material and is laminated on the cage cover 23. As Figure 3 and Figure 7 shown, the housing 22 and the cage cover 23 are fixed by a plurality of screws 24. Further, as Figure 3 and Figure 7 shown, a plurality of through holes 227 penetrating in the Z-axis direction are formed in the housing 22. The plurality of through holes 227 are used to fix the liquid ejection head 20 to the carriage 18.

[0039] As Figure 5 and Figure 6 shown, a space S1 is formed in the +Z direction of the housing 22. The cage cover 23 has an inner bottom surface 232 substantially parallel to the XY plane. The inner bottom surface 232 has four openings 234 for inserting each of the four wiring components 78. The four openings 234 are arranged to extend in the Y-axis direction. Through the four openings 234 extending in the Y-axis direction, the inner bottom surface 232 has three beam portions 236 extending in the Y-axis direction. A space S2 is formed in the -Z direction with respect to the inner bottom surface 232, and a space S3 is formed in the +Z direction with respect to the inner bottom surface 232.

[0040] Additionally, the +Y direction and the -Y direction are an example of the "second direction".

[0041] As Figure 5 and Figure 6 shown, in the space S2 of the cage cover 23, a sealing member 25, a circuit board 26, and a cage 27 are housed. As Figure 5As shown, the circuit board 26 and the cage cover 23 are stacked on the cage 27 with a gap d1 in the Z-axis direction.

[0042] In addition, the Z-axis direction, that is, the +Z direction and the -Z direction, is an example of the "stacking direction".

[0043] The cage 27 has a first cage 271 and a second cage 272. In the space S2, the first cage 271 and the second cage 272 are stacked in order from the -Z direction. In the space S3 of the cage cover 23, a plurality of head chips 70 are accommodated, and the cage cover 23 is closed from the +Z direction by the fixing plate 29. In the space S1 of the housing 22, a filter unit G1 is accommodated. The filter unit G1 is stacked on the -Z direction, which is the side opposite to the circuit board 26 of the sealing member 25.

[0044] As Figure 5 and Figure 6 shown, the filter unit G1 is a flow channel structure body including a plurality of structural components 221, 222, and 223 stacked together. The structural components 221, 222, and 223 are components in which flow channels for ink are formed inside. The flow channels formed in the structural components 221, 222, and 223 are not shown in the figure. The above-mentioned filter is provided in the middle of the flow channel in the structural component 222. In addition, in Figure 3 , since the state where the filter unit G1 is fixed on the +Z direction surface of the housing 22 is shown, the filter unit G1 is not shown. In addition, instead of the filter unit G1, a flow channel component formed with a flow channel without a filter may be arranged. The filter unit G1 is formed by injection molding of a resin material. The filter unit G1 is composed of, for example, a thermoplastic resin or a thermosetting resin. The thermoplastic resin is, for example, Zylon, LCP, PPS, or PP. Zylon is a registered trademark. LCP is a liquid crystal polymer. PPS is polyphenylene sulfide. PP is polypropylene. The thermosetting resin is, for example, an epoxy resin or a phenolic resin.

[0045] The circuit board 26 is a board that relays drive signals Com, control signals SI, etc. supplied from the control device 12. On the circuit board 26, terminal portions 262 electrically connected to the wiring components 78 of the respective head chips 70 are formed, and a connector 264 for connecting to the control device 12 or other electronic components, etc. are mounted. The terminal portions 262 and the connector 264 are electrical joining portions. On the circuit board 26 of the present embodiment, four terminal portions 262 corresponding to the wiring components 78 of the four head chips 70 are formed in the -Z direction of the circuit board 26. In addition, a wiring component such as an FFC is connected to the connector 264, so that the circuit board 26 receives the drive signal Com from the control device 12 via the FFC. FFC is the abbreviation of Flexible Flat Cable. The connector 264 of the circuit board 26 of the present embodiment is arranged so as to be exposed from the respective ends in the +X direction and the -X direction.

[0046] In addition, as Figure 3 and Figure 5 shown, through holes 267 penetrating in the Z-axis direction are provided in the circuit board 26. Further, as Figure 5 shown, through holes 268 penetrating in the Z-axis direction are provided on the circuit board 26. The through holes 267 and the through holes 268 are used for positioning the circuit board 26 relative to the cage cover 23.

[0047] The first cage 271 and the second cage 272 are flat runner structures formed with runner channels for ink. The first cage 271 and the second cage 272 are formed by injection molding of a resin material. The first cage 271 and the second cage 272 are made of, for example, a thermoplastic resin or a thermosetting resin in the same manner as the filter unit G1. On the -Z direction surface of the first cage 271, a plurality of runners 273 protruding in the -Z direction are formed. In addition, although the first cage 271 has eight runners 273, in order to avoid complication of the drawings, in Figure 3 and Figure 6 , only two of the eight runners 273 are respectively marked with symbols for illustration. The plurality of runners 273 respectively pass through the through holes 3 formed in the circuit board 26 and communicate with the runners of the structural components 221, 222, 223 via the through holes of the sealing member 25.

[0048] In addition, in the second cage 272, a plurality of runners 274 extending in the Z-axis direction are formed. In addition, although the second cage 272 has eight runners 274, in order to avoid complication of the drawings, in Figure 3 and Figure 6Only two of the eight flow channels 274 are marked with symbols for illustration respectively. The multiple flow channels 274 communicate with the multiple flow channels 273 respectively. In each head chip 70, ink is introduced via each flow channel 273 and each flow channel 274.

[0049] Furthermore, the first cage 271 has four openings 275 for respectively inserting and penetrating four wiring components 78. Similarly, the second cage 272 has four openings 276 for respectively inserting and penetrating four wiring components 78. The openings 275 and the openings 276 are holes penetrating in the Z-axis direction.

[0050] The cage cover 23 is formed of a material having a higher thermal conductivity than the first cage 271 and the second cage 272. Materials having a higher thermal conductivity than resin materials are, for example, metals and ceramics having a higher thermal conductivity than resin materials. Preferred metals in the formation of the cage cover 23 are, for example, stainless steel, aluminum, titanium, and magnesium alloys. Ceramics having a higher thermal conductivity than resin materials are, for example, silicon carbide, aluminum nitride, sapphire, alumina, silicon nitride, cermet, and yttrium. In the following description, it is assumed that the cage cover 23 is formed of metal for illustration.

[0051] As described above, in the space S3 of the cage cover 23, a plurality of head chips 70 are accommodated. The plurality of head chips 70 are arranged side by side along the X-axis in the space S3. Each piezoelectric element 732 of each head chip 70 vibrates according to a drive signal Com supplied from the control device 12 via the circuit board 26 and the wiring component 78. By vibrating the piezoelectric element 732, the pressure in the pressure chamber C changes, so that the ink filled in the pressure chamber C is ejected from each nozzle N of the nozzle plate 74.

[0052] The fixing plate 29 is a flat plate-like component. The fixing plate 29 is formed of metal. Preferred metals in the formation of the fixing plate 29 are, for example, stainless steel. As Figure 3 and Figure 7 shown, in the fixing plate 29, four openings 292 having a shape corresponding to the nozzle plate 74 of each head chip 70 are formed for each head chip 70. The openings 292 are rectangular shapes elongated in the Y direction. In a state where the nozzle plate 74 is located inside the openings 292, each head chip 70 is fixed to the -Z-direction surface of the fixing plate 29 by, for example, an adhesive. Thus, the nozzles N of each nozzle row are respectively arranged in the openings 292. In addition, in Figure 7 order to prevent complication of the illustration, only a part of the nozzles N among the nozzles N of the four head chips 70 is shown.

[0053] As Figure 3 and Figure 6As shown, on the -Z direction surface of the housing 22, there are a plurality of tubes protruding in the -Z direction, and a plurality of flow channels 225 for introducing ink from the liquid containers C1 to C4 are respectively provided in the plurality of tubes. The flow channels 225 introduce the ink in the liquid containers C1 to C4 into the respective head chips 70 via the flow channels in the structural components 221, 222, 223, the flow channel 273 of the first cage 271, and the flow channel 274 of the second cage 272.

[0054] Figure 5 and Figure 6 The sealing member 25 shown is a plate-shaped elastic member. The sealing member 25 is formed with through holes that liquid-tightly connect the flow channels in the filter unit G1 and the flow channel 273 of the first cage 271.

[0055] 1.2. Regarding the positioning of the liquid ejection head 20 and the positioning of the circuit board 26

[0056] Use Figure 5 , Figure 6 , Figure 8 and Figure 9 to explain the positioning of the liquid ejection head 20 relative to the carriage 18 and the positioning of the circuit board 26 relative to the cage cover 23.

[0057] As Figure 5 and Figure 6 illustrated, the cage cover 23 has: a holding portion UC, a first flange portion U1, and a second flange portion U2. The holding portion UC holds the cage 27. The first flange portion U1 is provided so as to extend in the -X direction from the holding portion UC. Specifically, being provided so as to extend in the -X direction from the holding portion UC means that the -X direction end portion of the holding portion UC has a shape that extends a predetermined distance in the -X direction. The second flange portion U2 is provided so as to extend in the +X direction from the holding portion UC.

[0058] In addition, the -X direction is the direction in which the plurality of head chips 70 are arranged side by side, and is an example of the "first direction". The direction in which the plurality of head chips 70 are arranged side by side means the direction in which arbitrary positions of the respective plurality of head chips 70 are arranged side by side. The points of the respective positions of the plurality of head chips 70 can be, for example, the -Y direction end portions of the respective plurality of head chips 70, the centers of the respective plurality of head chips 70, or the +Y direction end portions of the respective plurality of head chips 70.

[0059] 1.2.1. Regarding the positioning of the liquid ejection head 20 relative to the carriage 18

[0060] As Figure 6 and Figure 7As illustrated, the first flange portion U1 has a first positioning portion PS1 for positioning the liquid ejection head 20 relative to the carriage 18. The second flange portion U2 has a second positioning portion PS2 for positioning the liquid ejection head 20 relative to the carriage 18. Specifically, the first positioning portion PS1 and the second positioning portion PS2 are substantially cylindrical bodies protruding in the +Z direction. Further, as Figure 6 shown, on the +Z-direction surface of the first positioning portion PS1, a recess RE1 recessed in the -Z direction is provided, and on the +Z-direction surface of the second positioning portion PS2, a recess RE2 recessed in the -Z direction is provided. In the following description, the recesses RE1 and RE2 may sometimes be collectively referred to as the "recess RE". Since the recess RE does not appear in the b-b cross section, in Figure 6 , the contour of the recess RE is represented by a dashed line. As Figure 6 shown, the second positioning portion PS2 is larger than the first positioning portion PS1 in the X-axis direction, which is the side-by-side direction of the first positioning portion PS1 and the second positioning portion PS2. Similarly, the recess RE2 is larger than the recess RE1 in the X-axis direction.

[0061] Figure 8 is a perspective view of the exterior of the carriage 18. Figure 9 is a perspective view of the exterior showing the state where the liquid ejection head 20 is mounted on the carriage 18. Figure 10 is an exploded perspective view when the liquid ejection head 20 is mounted on the carriage 18.

[0062] As Figure 8 , Figure 9 and Figure 10 shown, the carriage 18 has a spacer 181 and a carriage main body portion 182. Further, a first heater 185 and a second heater 186 are mounted on the carriage 18. The spacer 181 and the carriage main body portion 182 are formed of metal. Preferred metals for forming the spacer 181 and the carriage main body portion 182 are, for example, stainless steel, aluminum, titanium, and magnesium alloy. When viewed from above in the +Z direction, the carriage main body portion 182 is larger than the spacer 181. Hereinafter, the view from above in the +Z direction will be simply referred to as the "top view".

[0063] In addition, the first heater 185 and the second heater 186 correspond to the "heating portion".

[0064] As Figure 10As shown, the carriage main body 182 is a flat plate-shaped component substantially parallel to the XY plane and has a through hole 1821 penetrating in the Z-axis direction. When viewed from above, the edge of the through hole 1821 is substantially rectangular. The through hole 1821 expands in diameter toward the -Z direction. By expanding the diameter, a height difference is formed in the through hole 1821. By fitting the spacer 181 at the height difference formed in the through hole 1821, the carriage main body 182 holds the spacer 181. Further, the spacer 181 and the carriage main body 182 are fixed by a plurality of screws 191. In addition, the carriage main body 182 is not limited to a flat plate shape and may also be a concave shape including walls erected from the outer peripheral portion of the flat plate toward the -Z direction.

[0065] As Figure 8 and Figure 10 shown, the spacer 181 is a flat plate-shaped component substantially parallel to the XY plane and has a through hole 1811 penetrating in the Z-axis direction and a plurality of columnar portions 1812 protruding toward the -Z direction. When viewed from above, the through hole 1811 is substantially rectangular. The through hole 1811 expands in diameter toward the -Z direction, toward the -X direction, and toward the +X direction. By expanding in diameter toward the -X direction, a bottom portion 1815 is formed, and by expanding in diameter toward the +X direction, a bottom portion 1816 is formed. On the -Z direction surface of the bottom portion 1815, a convex portion 1817 protruding toward the -Z direction is provided. On the -Z direction surface of the bottom portion 1816, a convex portion 1818 protruding toward the -Z direction is provided.

[0066] In addition, although not shown in the drawings, the carriage 18 may also have a positioning portion capable of positioning the spacer 181 relative to the carriage main body 182. This positioning portion is constituted by, for example, a plurality of adjusting screws extending in the Y-axis direction.

[0067] The first heater 185 and the second heater 186 heat the ink filled inside each of the plurality of head chips 70 via the cage cover 23 and the fixing plate 29. In other words, by causing the heat generated by the first heater 185 and the second heater 186 to be conducted to the ink inside the head chips 70 via the cage cover 23 and the fixing plate 29, the ink inside each of the plurality of head chips 70 is heated. In the present embodiment, the first heater 185 and the second heater 186 are flat plate-shaped components substantially parallel to the XY plane. In addition, the respective shapes of the first heater 185 and the second heater 186 are not necessarily limited to components on a flat plate. The first heater 185 and the second heater 186 can adopt any heater such as a thin film heater or a ceramic heater. The first heater 185 has a through hole 1851 penetrating in the Z-axis direction. As Figure 8As shown, the convex portion 1817 is inserted through the through hole 1851, and the first heater 185 is placed on the bottom portion 1815. Similarly, as Figure 8 shown, the convex portion 1818 is inserted through the through hole 1861, and the second heater 186 is placed on the bottom portion 1816. Further, the liquid ejection head 20 is positioned relative to the carriage 18 by fitting the convex portion 1817 into the concave portion RE1 provided on the first positioning portion PS1 and fitting the convex portion 1818 into the concave portion RE2 provided on the second positioning portion PS2.

[0068] On several -Z direction surfaces of the plurality of columnar portions 1812, concave portions protruding in the +Z direction are provided. The plurality of screws 193 correspond one by one to the plurality of through holes 227 provided in the housing 22. By inserting each of the plurality of screws 193 through the corresponding through hole 227 and screwing them into the concave portion provided on any one of the plurality of columnar portions 1812, the liquid ejection head 20 is fixed to the spacer 181 of the carriage 18 at the position where the liquid ejection head 20 is positioned on the spacer 181 of the carriage 18.

[0069] 1.2.2. Regarding the positioning of the circuit board 26 relative to the carriage cover 23

[0070] As Figure 5 shown, the first flange portion U1 has a third positioning portion PS3 for implementing the positioning of the circuit board 26 relative to the carriage cover 23. The second flange portion U2 has a fourth positioning portion PS4 for implementing the positioning of the circuit board 26 relative to the carriage cover 23. Specifically, the third positioning portion PS3 and the fourth positioning portion PS4 are substantially cylindrical bodies protruding in the -Z direction.

[0071] As Figure 5 shown, by passing the third positioning portion PS3 through the through hole 267 and passing the fourth positioning portion PS4 through the through hole 268, the circuit board 26 is positioned relative to the carriage cover 23. The circuit board 26 and the carriage cover 23 are arranged with a gap d1 in the Z-axis direction. On the other hand, in the X-axis direction and the Y-axis direction perpendicular to the Z-axis direction, the circuit board 26 abuts against the third positioning portion PS3 and the fourth positioning portion PS4. The portions of the carriage cover 23 in contact with the circuit board 26 are only the third positioning portion PS3 and the fourth positioning portion PS4. Since the carriage cover 23 is formed of metal, no wiring is provided on the inner peripheral surfaces of the through hole 267 and the through hole 268 of the circuit board 26.

[0072] 1.3. The heat conduction path of the first heater 185

[0073] Use Figure 11 AndFigure 5 The heat conduction path of the first heater 185 will be described.

[0074] Figure 11 That is, Figure 8 A cross-sectional view taken along the line c-c of the state in which the liquid ejection head 20 shown is mounted on the carriage 18. The c-c cross-section is a cross-section parallel to the XZ plane. However, to prevent complication of the drawings, Figure 11 the cross-sectional view shown only shows the vicinity of the first positioning portion PS1. Further, in Figure 11 the cross-sectional view shown, in order to prevent complication of the drawings, the illustration inside the head chip 70 is omitted.

[0075] In Figure 11 , the heat conduction path HTP1 from the first heater 185 to the ink of the liquid ejection head 20 is shown. In Figure 11 , since the illustration inside the head chip 70 is omitted, the illustration of the heat conduction path inside the head chip 70 in the heat conduction path HTP1 is also omitted. In Figure 4 the heat conduction path inside the head chip 70 is shown.

[0076] First, Figure 11 , the heat conduction path from the first heater 185 to the head chip 70 will be described. The first heater 185 is placed on the bottom 1815 of the spacer 181. Further, as Figure 11 shown, the top end in the +Z direction of the first positioning portion PS1 abuts against the surface in the -Z direction of the first heater 185. The heat generated by the first heater 185 is conducted to the cage cover 23 through the convex portion 1817 of the spacer 181 and the top end in the +Z direction of the first positioning portion PS1. The cage cover 23 is formed of a metal with a high heat conductivity, so that heat is easily conducted. The cage cover 23 abuts against the second cage 272 formed of resin and the fixing plate 29 formed of metal. Since the heat conductivity of metal is higher than that of resin, the heat in the cage cover 23 is conducted to the fixing plate 29. The heat conducted to the fixing plate 29 is conducted into the head chip 70.

[0077] In addition, although in the present embodiment, the top end in the +Z direction of the first positioning portion PS1 abuts against the surface in the -Z direction of the first heater 185, the top end in the +Z direction of the first positioning portion PS1 may not abut against the surface in the -Z direction of the first heater 185. Even if the top end in the +Z direction of the first positioning portion PS1 does not abut against the surface in the -Z direction of the first heater 185, the heat generated by the first heater 185 can be conducted to the cage cover 23 through the convex portion 1817.

[0078] Next, Figure 4An explanation will be given of the heat conduction path within the head chip 70. On the fixed plate 29, a plastic part 75 abuts. The heat conducted to the fixed plate 29 is conducted to the flow path forming substrate 71 via the plastic part 75. Since the support body 754 constituting the plastic part 75 is formed of a metal with a relatively high heat conductivity, the heat of the support body 754 is conducted to the sealing plate 752. Although the sealing plate 752 is formed of a resin with a relatively low heat conductivity, since it is thinner than the flow path forming substrate 71, the heat conducted to the sealing plate 752 is conducted to the flow path forming substrate 71. The heat conducted to the flow path forming substrate 71 is conducted to the ink within the openings 712, supply flow paths 714, and communication flow paths 716. Based on the above, the ink within each of the respective internal parts of the plurality of head chips 70 is heated by the first heater 185.

[0079] In addition, as Figure 11 shown, a part of the drive circuit 781 is disposed within the opening 276 of the second carriage 272. The meaning that a part of the drive circuit 781 is disposed within the opening 276 refers to the fact that when observed in a direction perpendicular to the extending direction of the opening 276, that is, in a direction parallel to the XY plane, the drive circuit 781 and the opening 276 partially overlap.

[0080] Although not shown in the drawings, the second heater 186 also heats the ink within each of the respective internal parts of the plurality of head chips 70 via the carriage cover 23 and the fixed plate 29.

[0081] 1.4. Summary of the First Embodiment

[0082] As described above, the liquid ejection device 10 in the first embodiment includes: a liquid ejection head 20, a carriage 18, a first heater 185, and a second heater 186. The liquid ejection head 20 includes: a plurality of head chips 70, a carriage 27, a carriage cover 23, and a fixed plate 29. Each of the plurality of head chips 70 has a nozzle plate 74, and the nozzle plate 74 has nozzles N for ejecting ink. The carriage 27 holds the plurality of head chips 70 and has flow paths for supplying ink to each of the plurality of head chips 70, and is formed of resin. The carriage cover 23 houses the plurality of head chips 70 and the carriage 27, and is formed of a material with a higher heat conductivity than the carriage 27. The fixed plate 29 fixes the carriage cover 23 and the plurality of head chips 70, and is formed of metal. The carriage 18 mounts the liquid ejection head 20. The first heater 185 and the second heater 186 are mounted on the carriage 18, and heat the internal ink for each of the plurality of head chips 70 via the carriage cover 23 and the fixed plate 29.

[0083] In the case of using an ink such as UV ink that needs to be used at a high temperature, in order to improve the ejection performance, it is desirable to heat the ink near the head chip, and more preferably, the ink near the nozzle N. However, in a liquid ejection head that holds a plurality of head chips by a cage formed of a resin having a low thermal conductivity, it is difficult to heat the liquid inside each of the plurality of head chips from the outside of the liquid ejection head. In addition, a method of heating the ink in the head chip by using a heater disposed outside the liquid ejection head by forming a cage using a metal or ceramic having a higher thermal conductivity than the resin can be considered. However, since the shape of the flow path formed in the cage is complicated, it is difficult to accurately form the flow path formed in the cage using a metal or ceramic, and the manufacturing cost of the liquid ejection head increases.

[0084] Therefore, the liquid ejection head 20 in the present embodiment has a cage cover 23 formed of a material having a higher thermal conductivity than the resin. Therefore, the first heater 185 and the second heater 186 can heat the ink in the head chip 70 via the cage cover 23. Further, since the cage 27 having the flow path is formed of resin, an increase in the manufacturing cost of the liquid ejection head 20 can be suppressed. Moreover, compared with a structure in which the first heater 185 and the second heater 186 are provided in the liquid ejection head 20, the wiring of the first heater 185 and the second heater 186 becomes easier in the liquid ejection head 20 of the present embodiment. The reason why the wiring becomes easier is that in a structure in which the first heater 185 and the second heater 186 are provided in the liquid ejection head 20, it is necessary to consider the wiring of the first heater 185 and the second heater 186 in the liquid ejection head 20 and the joint portion between this wiring and the wiring outside the liquid ejection head 20. Further, compared with a structure in which the first heater 185 and the second heater 186 are provided in the liquid ejection head 20, the replacement of the liquid ejection head 20 becomes easier in the liquid ejection device 10 of the present embodiment because there is no joint portion between the wiring of the first heater 185 and the second heater 186 in the liquid ejection head 20 and the wiring outside the liquid ejection head 20.

[0085] The cage cover 23 has: a holding portion UC that holds the cage 27, a first flange portion U1 that is provided so as to extend in the -X direction in which a plurality of head chips 70 are arranged side by side from the holding portion UC, and a second flange portion U2 that is provided so as to extend in the +X direction from the holding portion UC. The first flange portion U1 has a first positioning portion PS1 for positioning the liquid ejection head 20 relative to the carriage 18. The second flange portion U2 has a second positioning portion PS2 for positioning the liquid ejection head 20 relative to the carriage 18. The first heater 185 heats the cage cover 23 via the first positioning portion PS1. In addition, the second heater 186 heats the cage cover 23 via the second positioning portion PS2.

[0086] In order to improve the printing quality, it is necessary to perform highly accurate positioning of the liquid ejection head 20 relative to the carriage 18. In the present embodiment, for this positioning, the first positioning portion PS1 that needs to contact the carriage 18 is included in the heat conduction path HTP1. In a manner where the first positioning portion PS1 is not included in the heat conduction path from the first heater 185 to the ink of the liquid ejection head 20, it is necessary to prepare a metal member for filling the gap between the carriage 18 and the cage cover 23. Therefore, compared with a manner where the first positioning portion PS1 is not included in the heat conduction path from the first heater 185 to the ink in the head chip 70, the present embodiment can reduce the number of components of the liquid ejection device 10, and thus the manufacture of the liquid ejection device 10 becomes easy.

[0087] The carriage 18 has a spacer 181 and a carriage main body portion 182. The spacer 181 is positioned relative to the liquid ejection head 20 by abutting against the first positioning portion PS1 and the second positioning portion PS2, and the spacer 181 is formed of metal. The carriage main body portion 182 holds the spacer 181 and is formed of metal. The first heater 185 and the second heater 186 heat the first positioning portion PS1 and the second positioning portion PS2 via the spacer 181 by heating the spacer 181.

[0088] As Figure 8 shown, etc., in order to hold the spacer 181, the carriage main body portion 182 is larger than the spacer 181 and has a larger surface area. When the surface area becomes large, heat radiation is likely to occur. Therefore, compared with a manner of heating the ink in the head chip 70 via the carriage main body portion 182, the present embodiment can suppress the heat dissipation due to heat radiation, and thus can suppress the reduction in the heating efficiency of the ink. The heating efficiency of the ink is the ratio of the heat for heating the ink in the head chip 70 to the heat generated by the first heater 185 and the second heater 186.

[0089] The liquid ejection head 20 includes a housing 22 formed of resin. The housing 22 is laminated on the side of the cage cover 23 opposite to the fixed plate 29 and has a flow path 225 for supplying liquid to the cage 27. The housing 22 is an example of a "flow path component".

[0090] By means of the housing 22 which is a flow path component formed of resin having a lower thermal conductivity than metal, it is possible to suppress the heat transferred to the cage cover 23 from dissipating in the -Z direction.

[0091] The liquid ejection head 20 has a circuit board 26 which is laminated on the cage 27 so as to be spaced apart from the cage cover 23 in the Z-axis direction. The cage cover 23 is formed of metal. The first flange portion U1 has a third positioning portion PS3 for positioning the circuit board 26 relative to the cage cover 23. The second flange portion U2 has a fourth positioning portion PS4 for positioning the circuit board 26 relative to the cage cover 23.

[0092] By making the third positioning portion PS3 and the fourth positioning portion PS4 located at positions away from each other from the center of the circuit board 26 in a top view as compared with the case where the third positioning portion PS3 and the fourth positioning portion PS4 are located near the center of the circuit board 26 in a top view, the positioning accuracy is improved. Therefore, for the first flange portion U1 and the second flange portion U2 which are spaced apart from each other in the X-axis direction, by the first flange portion U1 having the third positioning portion PS3 and the second flange portion U2 having the fourth positioning portion PS4, the circuit board 26 can be arranged with good accuracy as compared with the case where the holding portion UC has the third positioning portion PS3 and the fourth positioning portion PS4. In addition, although in the present embodiment, the cage cover 23 is formed of metal in order to heat the ink inside each of the plurality of head chips 70 from the outside of the liquid ejection head 20, since the circuit board 26 abuts against the cage cover 23 formed of metal which is also a conductive material only through the third positioning portion PS3 and the fourth positioning portion PS4, the insulation between the cage cover 23 and the circuit board 26 can be ensured.

[0093] The liquid ejection device 10 includes a wiring component 78 which is connected to any one of the plurality of head chips 70 together with the circuit board 26 and has a drive circuit 781. The first cage 271 has an opening 275 for the wiring component 78 to pass through. Similarly, the second cage 272 has an opening 276 for the wiring component 78 to pass through. A part of the drive circuit 781 is arranged in the opening 276.

[0094] By disposing a part of the drive circuit 781 within the opening 276 of the second cage 272 formed of resin, it is possible to suppress the abnormal operation of the drive circuit 781 caused by the cage cover 23 being heated to a high temperature by the first heater 185 and the second heater 186. Further, since the resin has insulating properties, even if the drive circuit 781 comes into contact with the opening 276, it is possible to suppress a short circuit in the wiring of the drive circuit 781.

[0095] The cage cover 23 has a beam portion 236 that is disposed between the cage 27 and the head chip 70 and extends in the Y-axis direction.

[0096] By heating the beam portion 236, it is possible to heat the plurality of head chips 70 disposed within the space S3 via the air within the space S3.

[0097] 2. Modification Example

[0098] Each of the embodiments exemplified above can be modified in various ways. Specific modification methods will be exemplified below. Two or more methods arbitrarily selected from the following examples can be appropriately combined within a non-conflicting range.

[0099] 2.1. First Modification Example

[0100] Although in the first embodiment, the carriage 18 is composed of the spacer 181 and the carriage main body portion 182, the spacer 181 and the carriage main body portion 182 can also be integrally formed for the carriage 18. In the first modification example, the carriage 18 is formed of metal. The first heater 185 and the second heater 186 heat the ink inside each of the plurality of head chips 70 via the carriage 18 in the first modification example, and the first positioning portion PS1 and the second positioning portion PS2.

[0101] 2.2. Second Modification Example

[0102] Although in the first embodiment and the first modification example, the housing 22 has the through hole 227 used for the screw 193 for fixing the liquid ejection head 20 relative to the carriage 18, it is not limited thereto. For example, the cage cover 23 can also have a through hole used for the screw for fixing the liquid ejection head 20 relative to the carriage 18. For example, the first flange portion U1 and the second flange portion U2 in the second modification example have the aforementioned through hole.

[0103] According to the second modification example, the first heater 185 and the second heater 186 can heat the ink in the head chip 70 via the screw that must come into contact with the carriage 18 in order to fix the liquid ejection head 20 to the carriage 18, so that the heating efficiency for the ink can be improved compared to the first embodiment.

[0104] 2.3. Third modification example

[0105] In the first embodiment and the second modification example, the carriage 18 may also have a heat insulating material.

[0106] Figure 12 Fig. is a cross-sectional view of the carriage 18A in the third modification example. More specifically, Figure 12 The cross-sectional view shown is the c-c cross-sectional view of the state where the liquid ejection head 20 shown in Figure 8 is mounted on the carriage 18A in the third modification example.

[0107] As Figure 12 shown, the carriage 18A has a spacer 181, a carriage main body portion 182, and a heat insulating material 183. The heat insulating material 183 is disposed between the spacer 181 and the carriage main body portion 182 and has a lower thermal conductivity than the cage cover 23. Materials having a lower thermal conductivity than the cage cover 23 are, for example, resin and ceramics having a lower thermal conductivity than the metal forming the cage cover 23. In addition, preferably, the heat insulating material 183 has a lower thermal conductivity than the cage 27.

[0108] As described above, according to the third modification example, it is possible to suppress the case where the heat generated by the first heater 185 and the second heater 186 is conducted to the carriage main body portion 182 and dissipated.

[0109] 2.4. Fourth modification example

[0110] Although in the first embodiment, the second modification example, and the third modification example, the recesses RE are provided on the first positioning portion PS1 and the second positioning portion PS2, and the spacer 181 has the convex portions 1817 and 1818, this is not limiting. For example, the following method may also be adopted, that is, the spacer 181 has a recess recessed in the +Z direction, and the first positioning portion PS1 and the second positioning portion PS2 have protrusions protruding in the -Z direction. By fitting the recess of the spacer 181 with the protrusions of the first positioning portion PS1 and the second positioning portion PS2, the liquid ejection head 20 is positioned relative to the carriage 18.

[0111] 2.5. Fifth modification example

[0112] Although in each of the above-described ways, the plurality of head chips 70 are arranged in a row in the X-axis direction, they may also be arranged in a staggered manner in the X-axis direction. For example, the following way may also be adopted, that is, the head chip 70 closest to the -X direction and the head chip 70 third from the -X direction are arranged side by side along a first straight line parallel to the X-axis direction, and the head chip 70 second from the -X direction and the head chip 70 closest to the +Z direction are arranged side by side along a second straight line parallel to the first straight line.

[0113] 2.6. Sixth modification example

[0114] Although in each of the above-described ways, a part of the drive circuit 781 is arranged in the opening 276 of the second cage 272, all of the drive circuit 781 may also be arranged in the opening 276 of the second cage 272. Alternatively, the following way may also be adopted, that is, a part of the drive circuit 781 is arranged in the opening 275 of the first cage 271, and the remaining part of the drive circuit 781 is arranged in the opening 276 of the second cage 272.

[0115] 2.7. Seventh modification example

[0116] Although in each of the above-described ways, the plurality of head chips 70 each extend in the Y-axis direction, it is not limited to a direction orthogonal to the X-axis direction like the Y-axis direction, and they may also extend in a direction intersecting the X-axis direction. In the case where the plurality of head chips 70 respectively extend in a specific direction intersecting the X-axis direction, the beam portion 236 of the cage cover 23 also extends in the aforementioned specific direction.

[0117] 2.8. Eighth modification example

[0118] Although in each of the above-described ways, the first heater 185 is placed on the bottom 1815 and the second heater 186 is placed on the bottom 1816, it is not limited to this. For example, the first heater 185 may be attached to the -X direction side surface of the holding portion UC of the cage cover 23, or may be attached to the -X direction surface of the fixing plate 29, or may be attached to the +Y direction side surface of the holding portion UC of the cage cover 23. Similarly, the second heater 186 may be attached to the +X direction side surface of the holding portion UC, or may be attached to the -Y direction side surface of the holding portion UC of the cage cover 23. In addition, the first heater 185 may also be arranged on the part of the carriage 18 located in the +Y direction with respect to the side surface so as to heat the +Y direction side surface of the holding portion UC of the cage cover 23. Similarly, the second heater 186 may also be arranged on the part of the carriage 18 located in the -Y direction with respect to the side surface so as to heat the -Y direction side surface of the holding portion UC of the cage cover 23.

[0119] 2.9. Ninth Modified Example

[0120] Although in each of the above-described modes, an example is given of a serial head in which the carriage 18 carrying the liquid ejection head 20 reciprocates repeatedly in the X direction, the present invention can also be applied to a line head in which the liquid ejection heads 20 are arranged across the entire width of the medium 11.

[0121] 2.10. Tenth Modified Example

[0122] Although in the above-described embodiment, an example is given of the liquid ejection head 20 of the piezoelectric method that applies mechanical vibration to the pressure chamber C by the piezoelectric element 732, a liquid ejection head of the thermal method that uses a heating element to generate bubbles inside the pressure chamber C by heating can also be adopted.

[0123] 2.11. Eleventh Modified Example

[0124] Although in the above-described embodiment, an example is given of the structure in which the flow path 225 of the housing 22 supplies ink from the liquid storage portion 17 mounted on the carriage 18, a structure in which ink is supplied from a liquid storage portion disposed outside the carriage 18 via a tube can also be adopted.

[0125] 2.12. Twelfth Modified Example

[0126] The opening shape of one of the through holes 267 and 268 may also be an elongated ellipse in the X-axis direction, which is the juxtaposition direction of the through holes 267 and 268. Even if the positions of the third positioning portion PS3 and the fourth positioning portion PS4 are shifted in the X-axis direction due to manufacturing errors, it is possible to suppress the case where the third positioning portion PS3 and the fourth positioning portion PS4 cannot be inserted into the through holes 267 and 268.

[0127] 2.13. Other Modified Examples

[0128] In addition to being applicable to dedicated printing equipment, the liquid ejection device 10 illustrated in the above-described embodiment can also be adopted in various equipment such as a facsimile machine or a copying machine. Obviously, the use of the liquid ejection device 10 of the present invention is not limited to printing. For example, a liquid ejection device that ejects a solution of a color material can be used as a manufacturing device for forming a color filter of a liquid crystal display device and an organic EL display, etc. EL is an abbreviation for ElectroLuminescence. FED is an abbreviation for Field Emission Display. In addition, a liquid ejection device that ejects a solution of a conductive material can be used as a manufacturing device for forming wirings or electrodes of a wiring substrate.

[0129] 3. Supplementary Note

[0130] According to the method exemplified above, the following structure can be grasped, for example.

[0131] The liquid ejection device according to Mode 1 as a preferred mode includes: a liquid ejection head having a plurality of head chips, a carriage, a carriage cover, and a fixing plate. Among them, the head chip has a nozzle plate, and the nozzle plate has nozzles for ejecting liquid. The carriage holds the plurality of head chips and has flow paths for supplying liquid to each of the plurality of head chips, and the carriage is formed of resin. The carriage cover houses the plurality of head chips and the carriage, and the carriage cover is formed of a material having a higher thermal conductivity than the carriage. The fixing plate fixes the carriage cover and the plurality of head chips, and the fixing plate is formed of metal; a carriage on which the liquid ejection head is mounted; and a heating unit mounted on the carriage and heating the liquid inside each of the plurality of head chips via the carriage cover and the fixing plate.

[0132] The liquid ejection head according to Mode 1 has a carriage cover formed of a material having a higher thermal conductivity than resin. Therefore, the heating unit can heat the ink in the head chip via the carriage cover. Further, since the carriage having flow paths is formed of resin, an increase in the manufacturing cost of the liquid ejection head can be suppressed.

[0133] In Mode 2 as a specific example of Mode 1, the carriage cover has: a holding portion for holding the carriage; a first flange portion provided so as to extend in a first direction in which the plurality of head chips are arranged side by side from the holding portion; and a second flange portion provided so as to extend in a direction opposite to the first direction from the holding portion. The first flange portion has a first positioning portion for positioning the liquid ejection head relative to the carriage, and the second flange portion has a second positioning portion for positioning the liquid ejection head relative to the carriage. The heating unit heats the carriage cover via the first positioning portion and the second positioning portion.

[0134] According to Mode 2, since the number of components of the liquid ejection device can be reduced compared to a mode in which the first positioning portion and the second positioning portion are not included in the heat conduction path from the heating unit to the ink, the manufacture of the liquid ejection device becomes easier.

[0135] In Mode 3 as a specific example of Mode 2, holes are formed in the carriage cover, and screws for fixing the liquid ejection head to the carriage are inserted through the holes.

[0136] The heating unit can heat the liquid in the head chip via the screws that must be in contact with the carriage in order to fix the liquid ejection head to the carriage, thereby improving the heating efficiency of the liquid compared to Mode 1.

[0137] In Mode 4, which is a specific example of Mode 2 or Mode 3, the carriage has a spacer and a carriage main body. The spacer is positioned with the liquid ejection head by abutting against the first positioning portion and the second positioning portion, and the spacer is formed of metal. The carriage main body holds the spacer and is formed of metal. The heating unit heats the first positioning portion and the second positioning portion via the spacer by heating the spacer.

[0138] According to Mode 4, since the heat dissipation due to thermal radiation can be suppressed compared to the mode of heating the liquid in the head chip via the carriage main body, the reduction in the heating efficiency of the liquid can be suppressed.

[0139] In Mode 5, which is a specific example of Mode 4, the carriage further includes a heat insulating material. The heat insulating material is provided between the spacer and the carriage main body and has a lower thermal conductivity than the carriage cover.

[0140] According to Mode 5, the situation where the heat generated by the heating unit is conducted to the carriage main body can be suppressed.

[0141] In Mode 6, which is a specific example of any one of Modes 1 to 5, the liquid ejection head includes a flow path member formed of resin that is laminated on the side of the carriage cover opposite to the fixed plate and has a flow path for supplying liquid to the carriage.

[0142] According to Mode 6, the heat conducted to the carriage cover can be suppressed from dissipating to the side of the carriage cover opposite to the fixed plate by the flow path member formed of resin having a lower thermal conductivity than metal.

[0143] In Mode 7, which is a specific example of any one of Modes 1 to 6, the liquid ejection head has a circuit board laminated on the cage in such a manner as to be spaced apart from the cage cover in the stacking direction. The cage cover has: a holding portion for holding the cage; a first flange portion provided in such a manner as to be located in a first direction in which the plurality of head chips are arranged side by side starting from the holding portion; and a second flange portion provided in a direction opposite to the first direction. The cage cover is formed of metal. The first flange portion has a third positioning portion for positioning the circuit board relative to the cage cover, and the second flange portion has a fourth positioning portion for positioning the circuit board relative to the cage cover.

[0144] In Mode 7, although the cage cover is formed of metal in order to heat the ink in the head chip from the outside of the liquid ejection head, since the circuit board abuts against the cage cover formed of metal, which is also a conductive material, only through the third positioning portion and the fourth positioning portion, the insulation between the cage cover and the circuit board can be ensured.

[0145] In Mode 8, which is a specific example of Mode 7, a wiring component is provided. The wiring component is connected to the circuit board and one of the plurality of head chips and has a drive circuit. The cage has an opening for inserting the wiring component, and a part or all of the drive circuit is disposed in the opening.

[0146] According to Mode 8, it is possible to suppress a situation where the drive circuit malfunctions due to the cage cover, which becomes high temperature due to heating by the heating unit, by disposing a part or all of the drive circuit in the opening of the cage formed of resin. Further, since the resin has insulation properties, even if the drive circuit comes into contact with the opening of the cage, it is possible to suppress a short circuit in the wiring of the drive circuit.

[0147] In Mode 9, which is a specific example of any one of Modes 1 to 8, the cage cover has a beam portion provided between the cage and the head chip and extending in a second direction intersecting the first direction in which the plurality of head chips are arranged side by side.

[0148] According to Mode 9, it is possible to heat the plurality of head chips disposed in the space by heating the beam portion and then through the air in the space of which the beam portion is a part of the wall surface.

[0149] The liquid ejection head according to Mode 10 as a preferred mode is a liquid ejection head mounted on a carriage equipped with a heating unit. The liquid ejection head includes: a plurality of head chips, each of which has a nozzle plate with nozzles for ejecting liquid; a retainer that holds the plurality of head chips and has flow channels for supplying liquid to each of the plurality of head chips, and the retainer is formed of resin; a retainer cover that houses the plurality of head chips and the retainer, and the retainer cover is formed of a material with a higher thermal conductivity than the retainer; a fixing plate on which the retainer cover and the plurality of head chips are fixed, and the fixing plate is formed of metal. The liquid inside each of the plurality of head chips is heated by the heating unit through the retainer cover and the fixing plate.

[0150] The liquid ejection head according to Mode 10 has a retainer cover formed of a material with a higher thermal conductivity than resin. Therefore, the heating unit can heat the ink in the head chip through the retainer cover. Further, since the retainer with flow channels is formed of resin, an increase in the manufacturing cost of the liquid ejection head can be suppressed.

[0151] Symbol Explanation

[0152] 10…Liquid ejecting device; 11…Medium; 12…Control device; 14…Delivery mechanism; 17…Liquid storage section; 18…Carriage; 18A…Carriage; 20…Liquid ejection head; 22…Housing; 23…Carriage cover; 24, 191, 193…Screws; 25…Sealing member; 26…Circuit board; 27…Carriage; 29…Fixed plate; 70…Head chip; 71…Flow path forming substrate; 72…Pressure chamber forming substrate; 73…Vibration plate; 74…Nozzle plate; 75…Plastic part; 76…Protection plate; 77…Support body; 78…Wiring component; 181…Separator; 182…Carriage main body section; 183…Heat insulating material; 185…First heater; 186…Second heater; 202…Flow path unit; 204…Head main body; 221, 222, 223…Structural components; 225…Flow path; 227…Through hole; 232…Inner bottom surface; 234…Opening; 236…Beam section; 262…Terminal section; 264…Connector; 267, 268…Through holes; 271…First carriage; 272…Second carriage; 273…Flow path; 275, 276, 292, 712, 722…Openings; 714…Supply flow path; 716…Communication flow path; 732…Piezoelectric element; 752…Sealing plate; 754…Support body; 772…Space; 774…Supply port; 781…Drive circuit; 1811…Through hole; 1812…Columnar section; 1815, 1816…Bottoms; 1817, 1818…Protrusions; 1821…Through hole; 1851…Through hole; 1861…Through hole; C…Pressure chamber; C1, C2, C3, C4…Liquid containers; Com…Drive signal; G1…Flow path component; HTP1…Heat conduction path; N…Nozzle; PS1…First positioning section; PS2…Second positioning section; PS3…Third positioning section; PS4…Fourth positioning section; R…Liquid retention chamber; RE1, RE2…Recesses; S1, S2, S3…Spaces; SI…Control signal; U1…First flange section; U2…Second flange section; UC…Retention section.

Claims

1. A liquid ejection device, characterized in that, Comprising: A liquid ejection head having a plurality of head chips, a carriage, a carriage cover, and a fixing plate, wherein each of the plurality of head chips has a nozzle plate having a plurality of nozzles for ejecting liquid, the carriage holds the plurality of head chips and has flow channels for supplying liquid to each of the plurality of head chips, and the carriage is formed of resin, the carriage cover houses the plurality of head chips and the carriage, and the carriage cover is formed of a material having a higher thermal conductivity than the carriage, the fixing plate has the carriage cover and the plurality of head chips fixed thereto and is formed with a plurality of openings for exposing the plurality of nozzle plates respectively, and the fixing plate is formed of metal; A carriage on which the liquid ejection head is mounted; A heating unit mounted on the carriage and heating the liquid inside each of the plurality of head chips via the carriage cover and the fixing plate.

2. The liquid ejection device according to claim 1, wherein The carriage cover has: a holding portion for holding the carriage; a first flange portion provided so as to extend in a first direction in which the plurality of head chips are arranged from the holding portion; and a second flange portion provided so as to extend in a direction opposite to the first direction from the holding portion, The first flange portion has a first positioning portion for positioning the liquid ejection head relative to the carriage, The second flange portion has a second positioning portion for positioning the liquid ejection head relative to the carriage, The heating unit heats the carriage cover via the first positioning portion and the second positioning portion.

3. The liquid ejection device according to claim 2, wherein A hole is formed in the carriage cover, and a screw for fixing the liquid ejection head to the carriage is inserted through the hole.

4. The liquid ejection device according to claim 2 or 3, wherein The carriage has a spacer and a carriage main body portion, the spacer is positioned with the liquid ejection head by abutting against the first positioning portion and the second positioning portion and the spacer is formed of metal, the carriage main body portion holds the spacer and the carriage main body portion is formed of metal, The heating unit heats the first positioning portion and the second positioning portion via the spacer by heating the spacer.

5. The liquid ejection device according to claim 4, wherein The carriage further includes a heat insulating material provided between the spacer and the carriage main body portion and having a lower thermal conductivity than the carriage cover.

6. The liquid ejection device according to claim 1, wherein The liquid ejection head includes a resinous flow channel member laminated on the side of the carriage cover opposite to the fixing plate and having flow channels for supplying liquid to the carriage.

7. The liquid ejection device according to claim 1, wherein The liquid ejecting head includes a circuit substrate stacked on the holder so as to be spaced apart from the holder cover in a stacking direction. The holder cover has: a holding portion that holds the holder; a first flange portion that is arranged in a manner that is located in a first direction in which the plurality of head chips are arranged side by side from the holding portion; and a second flange portion that is arranged in a direction opposite to the first direction. The cage cover is formed of metal, The first flange portion has a third positioning portion for positioning the circuit substrate relative to the holder cover. The second flange portion includes a fourth positioning portion for positioning the circuit board relative to the holder cover.

8. The liquid ejecting device according to claim 7, wherein A wiring member is provided, the wiring member being connected to the circuit substrate and one of the plurality of head chips and having a drive circuit, The holding frame has an opening for inserting the wiring component. A part or the entirety of the driving circuit is disposed in the opening.

9. The liquid ejecting device according to claim 1, wherein The holder cover includes a beam portion that is provided between the holder and the head chips and extends in a second direction intersecting with a first direction in which the plurality of head chips are arranged side by side.

10. The liquid ejecting device according to claim 1, wherein The cage cover has: a first positioning portion for positioning the liquid ejecting head relative to the carriage, a second positioning portion for positioning the liquid ejecting head relative to the carriage, The heating portion heats the holder cover via the first positioning portion and the second positioning portion.

11. A liquid ejecting head, characterized in that: The liquid ejecting head is mounted on a carriage equipped with a heating unit, and includes: a plurality of head chips, each of the plurality of head chips having a nozzle plate, the nozzle plate having a plurality of nozzles for ejecting liquid; a holder that holds the plurality of head chips and has a flow channel for supplying liquid to each of the plurality of head chips, wherein the holder is formed of resin; a holder cover for housing the plurality of head chips and the holder, wherein the holder cover is formed of a material having a higher thermal conductivity than that of the holder; A fixing plate on which the holder cover and the plurality of head chips are fixed and formed with a plurality of openings for respectively exposing the plurality of nozzle plates, and the fixing plate is formed of metal. Liquid inside each of the plurality of head chips is heated by the heating portion through the holder cover and the fixing plate.

12. The liquid ejecting head according to claim 11, wherein The cage cover has: a first positioning portion for positioning the liquid ejecting head relative to the carriage, a second positioning portion for positioning the liquid ejecting head relative to the carriage, The heating portion heats the holder cover via the first positioning portion and the second positioning portion.

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