Inkjet head and inkjet recording device

Abstract

To improve heat releasing property of an inkjet head while stably securing positioning accuracy of the inkjet head relative to a fitting base.SOLUTION: An inkjet head includes: a housing including a part to be fitted that is fitted while being placed in an edge part of a through-hole of a fitting base; and a positioning member positioned between a contact surface to the fitting base in the housing and an opposite surface thereof and positioning the housing. The heat conductivity of the housing is larger than the heat conductivity of the positioning member. The thermal expansion coefficient of the positioning member is smaller than the thermal expansion coefficient of the housing.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to an inkjet head and an inkjet recording apparatus. [Background technology]

[0002] Prior art inkjet heads are, for example, those shown in Patent Documents 1 and 2. In the inkjet heads described in Patent Documents 1 and 2, the following configuration is adopted to position the inkjet head relative to a mounting base and to release heat generated within the inkjet head to the mounting base side.

[0003] The inkjet head described in Patent Document 1 (referred to as an inkjet recording head in Patent Document 1) has a metal base plate at its bottom. The inkjet head can be positioned relative to the mounting base (referred to as a carriage in Patent Document 1) by abutting the base plate against a reference member (referred to as a positioning member in Patent Document 1) provided on the mounting base to serve as a reference for positioning the inkjet. In addition, by placing the base plate on (contacting) the mounting base, heat generated within the inkjet head can be released to the mounting base side.

[0004] In the inkjet head described in Patent Document 2, the inkjet head can be positioned relative to the mounting base by positioning the fixed body on a reference plate fixed to the mounting base (referred to as a mounting plate in Patent Document 2). In addition, a heat sink is thermally connected to the reference plate, so that heat generated within the inkjet head can be released to the mounting base side. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2005-29044 A [Patent Document 2] JP 2015-150761 A Summary of the Invention [Problem to be solved by the invention]

[0006] In the inkjet head described in Patent Document 1, the base plate has a positioning function for positioning the inkjet head on the mounting base, and a heat dissipation function for dissipating heat generated in the inkjet head to the mounting base. In other words, the base plate is a positioning member having a positioning function and a heat dissipation member having a heat dissipation function. Therefore, if the thermal conductivity of the base plate is increased in order to improve the heat dissipation of the inkjet head, the linear expansion coefficient of the base plate increases, and the positioning accuracy of the inkjet head relative to the mounting base decreases.

[0007] Furthermore, in the inkjet head described in Patent Document 2, the heat sink is not in contact with the mounting base, which means that the heat generated inside the inkjet head cannot be efficiently dissipated to the mounting base, making it difficult to improve the heat dissipation performance of the inkjet head.

[0008] SUMMARY OF THE PRESENTLY PREFERRED EMBODIMENTS An object of the present invention is to provide an inkjet head and an inkjet printing apparatus that can improve the heat dissipation of the inkjet head while stably ensuring the positioning accuracy of the inkjet head relative to the mounting base. [Means for solving the problem]

[0009] One aspect of the inkjet head according to the present invention is a housing having a mounting portion that is placed on an edge of a through hole of a mounting base and attached to the housing; a nozzle provided on a bottom side of the housing for ejecting ink; a positioning member for positioning the housing, the positioning member being located between a contact surface of the housing with the mounting base and an opposing surface of the contact surface, the positioning member being capable of coming into contact with a reference member provided on the mounting base so as to serve as a reference for positioning the housing, The thermal conductivity of the housing is greater than the thermal conductivity of the positioning member, and the thermal expansion coefficient of the positioning member is smaller than the thermal expansion coefficient of the housing.

[0010] One aspect of the inkjet recording apparatus according to the present invention is to The inkjet head is provided as described above. Effect of the Invention

[0011] According to the present invention, it is possible to improve the heat dissipation performance of the inkjet head while stably ensuring the positioning accuracy of the inkjet head with respect to the mounting base. [Brief description of the drawings]

[0012] [Figure 1] FIG. 1 is a schematic front view of an inkjet recording apparatus according to this embodiment. [Diagram 2] FIG. 2 is a schematic bottom view of the head unit according to this embodiment, showing a state in which a plurality of inkjet heads are attached to a carriage. [Diagram 3] FIG. 3 is a schematic plan view of the inkjet head according to this embodiment, showing the inkjet head attached to the carriage. [Figure 4] FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. [Diagram 5] FIG. 5 is a schematic perspective view of the inkjet head according to the present embodiment. [Figure 6] FIG. 6 is a schematic side view of the ink-jet head according to the present embodiment. [Figure 7] FIG. 7 is a schematic plan view of the inkjet head according to the present embodiment. [Figure 8]FIG. 8 is a schematic bottom view of the inkjet head according to the present embodiment. [Figure 9] FIG. 9 is a schematic bottom view of an ink-jet head according to Modification 1 of the present embodiment. [Figure 10] FIG. 10 is a schematic bottom view of the ink-jet head according to the first modified example of the present embodiment. [Figure 11] FIG. 11 is a schematic plan view of an ink-jet head according to the second modification of the present embodiment. [Figure 12] FIG. 12 is a schematic bottom view of an ink-jet head according to the second modified example of the present embodiment. [Figure 13] FIG. 13 is a schematic perspective view of an ink-jet head according to a third modified example of the present embodiment. [Figure 14] FIG. 14 is a schematic perspective view of an ink-jet head according to a fourth modified example of the present embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, this embodiment will be described with reference to the drawings. In this embodiment, the transport direction refers to the transport direction in which the recording medium is transported. The downstream side refers to the downstream side in the transport direction, and the upstream side refers to the upstream side in the transport direction. In this embodiment, the X-axis direction refers to the main scanning direction, which is a direction perpendicular to the transport direction. The Y-axis direction refers to the sub-scanning direction, which is the transport direction. The Z-axis direction refers to the direction perpendicular to the X-axis and Y-axis directions.

[0014] The overall configuration of an inkjet recording apparatus 10 according to this embodiment will be described with reference to Figures 1 and 2. Figure 1 is a schematic front view of the inkjet recording apparatus 10 according to this embodiment. Figure 2 is a schematic bottom view of a head unit 42 according to this embodiment, showing a state in which a plurality of inkjet heads 46 are attached to a carriage 44.

[0015] As shown in FIG. 1, the inkjet recording apparatus 10 according to the present embodiment is a single-pass type recording apparatus that forms a color image on the recording medium P by ejecting four color inks toward the recording medium P at appropriate timing while moving the recording medium P in the conveying direction. As the recording medium P, in addition to paper such as plain paper and coated paper, various media capable of fixing the ink that has landed on the surface, such as fabric and resin film, can be used. In the inkjet recording apparatus 10, ink that changes phase between a gel state and a sol state (liquid state) depending on temperature is used. For example, energy ray irradiation type ink such as UV ink that is in a gel state at room temperature, changes to a sol state when heated, and is solidified when irradiated with energy rays during image formation can be used.

[0016] The inkjet recording device 10 includes a device body 12 extending in the left-right direction in Fig. 1. The device body 12 includes a center frame 14, a first side frame 16 disposed on one side of the center frame 14, and a second side frame 18 disposed on the other side of the center frame 14.

[0017] The first side frame 16 is provided with a paper feed section 20 for feeding recording media P. The paper feed section 20 has a plate-shaped paper feed tray 22 for placing the recording media P thereon, and the paper feed tray 22 is provided on the first side frame 16 so as to be movable in the vertical direction. The paper feed tray 22 is configured to move up and down depending on the amount of recording media P to be placed on it, and the uppermost recording medium P is held at a predetermined height position.

[0018] The paper feed unit 20 has a transport section 24 for transporting the recording medium P sent out from the paper feed tray 22 in the transport direction, and the transport section 24 is provided from the first side frame 16 to the center frame 14. The transport section 24 has a plurality of rotatable support rollers 26 and an endless belt 28 provided to be wound around the plurality of support rollers 26. The belt 28 is caused to circulate by the rotation of the plurality of support rollers 26, thereby transporting the recording medium P sent out from the paper feed tray 22 in the transport direction.

[0019] The center frame 14 is provided with an image forming section 30 for ejecting ink onto the recording medium P to form an image. The image forming section 30 has an image forming drum 32 that supports the recording medium P, and the image forming drum 32 is rotatably provided on the center frame 14. With the recording medium P supported on the outer circumferential surface (conveyance surface) of the image forming drum 32, the image forming drum 32 is rotated by driving a motor (not shown) for the image forming drum, thereby conveying the recording medium P in the conveyance direction. The image forming drum 32 has a claw portion (not shown) that presses the edge of the recording medium P, and an adsorption portion (not shown) that adsorbs the recording medium P.

[0020] The image forming section 30 has a delivery unit 34 for delivering the recording medium P from the transport section 24 to the image forming drum 32, and the delivery unit 34 is provided between the transport section 24 and the image forming drum 32 in the center frame 14. The delivery unit 34 has a swing arm 36 that supports one end of the recording medium P transported by the transport section 24, and a delivery drum 38 that delivers the recording medium P supported by the swing arm 36 to the image forming drum 32. One end of the recording medium P on the transport section 24 is supported by the swing arm 36 and delivered to the delivery drum 38, so that the recording medium P is delivered from the delivery drum 38 to the image forming drum 32.

[0021] The image forming section 30 has a media heating section 40 for heating the recording medium P supported on the image forming drum 32, and the media heating section 40 is provided on the downstream side of the delivery drum 38 in the center frame 14. The media heating section 40 is disposed facing the outer circumferential surface of the image forming drum 32. The media heating section 40 has, for example, an infrared heater or the like, and heats the image forming drum 32 and the recording medium P so that the temperature of the recording medium P transported by the image forming drum 32 falls within a predetermined range.

[0022] As shown in FIG. 1 and FIG. 2, the image forming section 30 has a plurality of head units 42 that eject ink onto the recording medium P carried by the image forming drum 32 to form an image, and the plurality of head units 42 are disposed downstream of the medium heating section 40. The plurality of head units 42 are units corresponding to four colors of ink, namely, yellow (Y), magenta (M), cyan (C), and black (K). The plurality of head units 42 corresponding to the four colors of ink, Y, M, C, and K, are disposed at intervals from the upstream side along the conveying direction. Each head unit 42 is held by each carriage 44 that is provided on the center frame 14 so as to be movable in the main scanning direction. In other words, each head unit 42 is provided on the center frame 14 so as to be movable in the main scanning direction via each carriage 44. Each carriage 44 is made of, for example, an aluminum alloy.

[0023] Each head unit 42 has a plurality of inkjet heads 46 that eject ink onto the recording medium P, and the plurality of inkjet heads 46 are provided on a carriage 44 as an attachment base. The plurality of inkjet heads 46 are arranged, for example, in a staggered pattern along the main scanning direction (X-axis direction). In other words, each head unit 42 constitutes a line head including the plurality of inkjet heads 46.

[0024] 1, the image forming unit 30 has a fixing unit 48 for fixing the ink onto the recording medium P, and the fixing unit 48 is provided downstream of the multiple head units 42 in the center frame 14. The fixing unit 48 is disposed facing the outer circumferential surface of the image forming drum 32. The fixing unit 48 has a light-emitting unit that irradiates energy rays such as ultraviolet rays. The light-emitting unit of the fixing unit 48 imparts a predetermined energy to the ink ejected onto the recording medium P, thereby curing the ink and fixing it to the recording medium P.

[0025] The image forming unit 30 has a delivery unit 50 that transports the recording medium P irradiated with energy rays from the image forming drum 32 in the transport direction. The delivery unit 50 is provided across the center frame 14 to the second side frame 18. The delivery unit 50 has a plurality of rotatable support rollers 52, an endless belt 54 provided so as to be wound around the plurality of support rollers 52, and a delivery drum 56 that delivers the recording medium P from the image forming drum 32 to the belt 54. The belt 54 is caused to travel in a circular manner by the rotation of the plurality of support rollers 52, thereby transporting the recording medium P sent out from the image forming drum 32 in the transport direction.

[0026] The second side frame 18 is provided with a paper discharge section 58 for discharging the recording medium P on which an image has been formed. The paper discharge section 58 has a plate-shaped paper discharge tray 60 on which the recording medium P on which an image has been formed is placed. The paper discharge section 58 stores the recording medium P until the user removes the recording medium P from the paper discharge tray 60.

[0027] Next, a specific configuration of the inkjet head 46 according to this embodiment will be described with reference to Figs. 3 to 8. Fig. 3 is a schematic plan view of the inkjet head 46 according to this embodiment, showing a state in which the inkjet head 46 is attached to the carriage 44. Fig. 4 is a cross-sectional view taken along line IV-IV in Fig. 3. Fig. 5 is a schematic perspective view of the inkjet head 46 according to this embodiment. Fig. 6 is a schematic side view of the inkjet head 46 according to this embodiment. Fig. 7 is a schematic plan view of the inkjet head 46 according to this embodiment. Fig. 8 is a schematic bottom view of the inkjet head 46 according to this embodiment.

[0028] 3 to 6, the inkjet head 46 according to this embodiment is provided on the carriage 44 as a mounting base as described above, and closes the through-hole 44h formed in the carriage 44. The inkjet head 46 also includes a housing 62, which is made of, for example, an aluminum alloy. The lower side of the housing 62 is open, and the shape of the housing 62 when viewed from above and the shape of the housing 62 when viewed from the bottom are both rectangular. Note that FIG. 3 representatively illustrates one inkjet head 46.

[0029] The housing 62 has flanges 64 as mounting portions on both sides in the X-axis direction (main scanning direction) of its upper portion. Each flange 64 of the housing 62 is placed on the edge of a through hole 44h on the upper surface of the carriage 44 and attached by a mounting bolt 66. Each flange 64 of the housing 62 has an insertion hole 64h for inserting the mounting bolt 66. A portion of the housing 62 below the flange 64 is disposed inside the through hole 44h of the carriage 44. Instead of having the flanges 64 on both sides in the X-axis direction of the upper portion of the housing 62, the housing 62 may have flanges on both sides in the Y-axis direction of the upper portion, or the housing 62 may have a rectangular frame-shaped flange on the outer periphery of the upper portion.

[0030] A first recess 64c is formed on a side surface along the Y-axis direction of one flange portion 64 of the housing 62, and the first recess 64c opens to a lower surface of the one flange portion 64. In addition, a second recess 64d is formed on a side surface along the X-axis direction of each flange portion 64 of the housing 62, and each second recess 64d opens to a lower surface of the corresponding flange portion 64.

[0031] As shown in Figs. 6 to 8, a box-shaped cover member 68 is provided on the upper side of the housing 62, and the cover member 68 is made of, for example, an aluminum alloy. The inside of the cover member 68 is in communication with the inside of the housing 62. A manifold 70 extending in the X-axis direction is provided inside the housing 62, and a common ink chamber (not shown) for storing ink is formed inside the manifold 70. A supply port 72 for supplying ink to the supply ink chamber is provided at a portion on one side in the X-axis direction on the top surface of the housing 62. A discharge port 74 for discharging ink from the supply ink chamber is provided at a portion on the other side in the X-axis direction on the top surface of the housing 62.

[0032] A head chip 76 is provided on the bottom side within the housing 62 via a rectangular frame-shaped receiving member 78, and a plurality of nozzles 76n for ejecting ink are formed in the head chip 76. In other words, a plurality of nozzles 76n for ejecting ink are provided on the bottom side of the housing 62. The opening on the lower side of the housing 62 is blocked by the head chip 76 and the receiving member 78. The receiving member 78 is made of, for example, stainless steel.

[0033] In the head chip 76, a plurality of pressure chambers (not shown) are formed for each nozzle 76n, and each pressure chamber is connected to a common ink chamber and a corresponding nozzle 76n. Each pressure chamber is configured to be pressurized by driving a driving element (not shown), such as a piezoelectric element or a heating element. Each nozzle 76n is configured to eject (send) ink when the corresponding pressure chamber is pressurized. In addition, a wiring board 80 for supplying power to the plurality of driving elements is provided inside the cover member 68. In other words, a wiring board 80 for causing the ejection operation of the plurality of nozzles 76n is provided inside the cover member 68.

[0034] A heater 82, such as a polyimide heater, that heats the ink in the common ink chamber is provided outside the manifold 70 inside the housing 62. This allows the ink in the common ink chamber to have a viscosity that allows it to be ejected from the multiple nozzles 76n.

[0035] As shown in FIG. 3 to FIG. 8, a piece-shaped first positioning member 84 for positioning the housing 62 (inkjet head 46) in the X-axis direction (main scanning direction) is provided in the first recess 64c of one flange portion 64 of the housing 62. The first positioning member 84 can abut against a pin-shaped first reference member 86 provided on the upper surface of the carriage 44 so as to serve as a reference for positioning the housing 62 in the X-axis direction. The first positioning member 84 has a first positioning surface 84f that can abut against the first reference member 86. In other words, the housing 62 is provided with one first positioning member 84 having the first positioning surface 84f. The first positioning member 84 may be attached to the first recess 64c of one flange portion 64 of the housing 62 by any of bonding, press-fitting, and screw fastening.

[0036] The first positioning member 84 is located between the contact surface of the housing 62 with the carriage 44 and the opposing surface thereof. Specifically, the first positioning member 84 is located between the upper and lower surfaces of the flange portion 64 of the housing 62. More specifically, the first positioning member 84 is disposed on the lower surface side of the flange portion 64 of the housing 62 (the contact surface side of the housing 62 with the carriage 44). The first positioning member 84 is made of, for example, a stainless steel alloy. Note that instead of providing one first positioning member 84 in the housing 62, two or more first positioning members 84 may be provided.

[0037] The second recess 64d of each flange 64 of the housing 62 is provided with a piece-shaped second positioning member 88 for positioning the housing 62 (inkjet head 46) in the Y-axis direction (sub-scanning direction). Each second positioning member 88 can abut against a pin-shaped second reference member 90 provided on the upper surface of the carriage 44 so as to serve as a reference for positioning the housing 62 in the Y-axis direction. Each second positioning member 88 has a second positioning surface 88f that can abut against the corresponding second reference member 90. In other words, the housing 62 is provided with two second positioning members 88 each having a second positioning surface 88f. The second positioning members 88 may be attached to the second recess 64d of each flange 64 of the housing 62 by any of bonding, press-fitting, and screw-fastening.

[0038] Each second positioning member 88 is located between the contact surface of the housing 62 with the carriage 44 and the opposing surface thereof. Specifically, each second positioning member 88 is located between the upper and lower surfaces of the flange portion 64 of the housing 62. More specifically, each second positioning member 88 is disposed on the lower surface side of the flange portion 64 of the housing 62 (the contact surface side of the housing 62 with the carriage 44). Each second positioning member 88 is made of, for example, a stainless steel alloy. Instead of providing two second positioning members 88 in the housing 62, three or more second positioning members 88 may be provided.

[0039] Next, the physical properties of the housing 62, the first positioning member 84, and the second positioning member 88 will be described with reference to FIGS.

[0040] 3 and 4, the thermal expansion coefficient of the housing 62 is larger than that of the first positioning member 84 and the second positioning member 88. In other words, the thermal expansion coefficient of the first positioning member 84 and the second positioning member 88 is smaller than that of the housing 62. Specifically, in a temperature environment of 20° C. or higher and 100° C. or lower, the linear expansion coefficient of the housing 62 is 18×10 -6 The linear expansion coefficient of the first positioning member 84 and the second positioning member 88 is 18×10 -6 is less than.

[0041] The thermal conductivity of the housing 62 is greater than that of the first positioning member 84 and the second positioning member 88. The thermal conductivity of the housing 62 is smaller than that of the carriage 44. In addition, the total volume of the one first positioning member 84 and the two second positioning members 88 is smaller than the volume of the housing 62. The elastic modulus of the first positioning member 84 and the second positioning member 88 is greater than the elastic modulus of the housing 62.

[0042] As described above, in the configuration of the inkjet head 46 according to this embodiment, the thermal expansion coefficients of the first positioning member 84 and the second positioning member 88 are smaller than the thermal expansion coefficient of the housing 62. Therefore, the amount of deformation of the first positioning member 84 and the second positioning member 88 due to changes in environmental temperature can be reduced, and the positioning accuracy of the inkjet head 46 relative to the carriage 44 can be stably ensured.

[0043] As described above, the thermal conductivity of the housing 62 is greater than that of the first positioning member 84 and the second positioning member 88. Each flange portion 64 of the housing 62 is placed on (in contact with) an edge portion of the through hole 44h in the upper surface of the carriage 44. Therefore, heat generated in the inkjet head 46, such as heat generated from the wiring board 80, can be efficiently dissipated to the carriage 44 side, and the heat dissipation property of the inkjet head 46 can be improved.

[0044] That is, according to this embodiment, the positioning accuracy of the inkjet head 46 relative to the carriage 44 can be stably ensured, while the heat dissipation property of the inkjet head 46 can be improved.

[0045] According to the configuration of the inkjet head 46 of this embodiment, as described above, the first positioning member 84 and the second positioning member 88 are located between the contact surface with the carriage 44 and the opposing surface of the housing 62. Therefore, according to this embodiment, the attachment state of the first positioning member 84 and the second positioning member 88 to the flange portion 64 can be stabilized, and the contact state between each flange portion 64 and the upper surface of the carriage 44 can be stabilized.

[0046] As described above, according to the configuration of the inkjet head 46 of this embodiment, the thermal conductivity of the housing 62 is greater than the thermal conductivity of the first positioning member 84 and the second positioning member 88. Therefore, according to this embodiment, heat generated within the inkjet head 46 can be dissipated more efficiently to the carriage 44 side, and the heat dissipation performance of the inkjet head 46 can be further improved.

[0047] According to the configuration of the inkjet head 46 of this embodiment, as described above, the first positioning member 84 and each of the second positioning members 88 are each disposed on the lower surface side of the flange portion 64 of the housing 62. Therefore, the first positioning member 84 abuts against the base side of the first reference member 86, and each of the second positioning members 88 abuts against the base side of the second reference member 90. As a result, according to this embodiment, it is possible to further improve the positioning accuracy of the inkjet head 46 with respect to the carriage 44.

[0048] According to the configuration of the inkjet head 46 of this embodiment, as described above, the first recess 64c of one flange portion 64 opens to the lower surface of one flange portion 64. The second recess 64d of each flange portion 64 opens to the lower surface of each flange portion 64. Therefore, the first positioning member 84 can be easily attached to the inside of the first recess 64c from the lower surface side of one flange portion 64, and the second positioning member 88 can be easily attached to the inside of the second recess 64d from the lower surface side of each flange portion 64. As a result, according to this embodiment, it is possible to improve the ease of assembly of the inkjet head 46.

[0049] According to the configuration of the inkjet head 46 of this embodiment, as described above, the thermal conductivity of the housing 62 is smaller than that of the carriage 44. In other words, the thermal conductivity of the carriage 44 is greater than that of the housing 62. Therefore, according to this embodiment, heat generated within the inkjet head 46 can be dissipated to the carriage 44 side more efficiently, and the heat dissipation properties of the inkjet head 46 can be further improved.

[0050] As described above, according to the configuration of the inkjet head 46 of this embodiment, the elastic modulus of the first positioning member 84 and the second positioning member 88 is greater than the elastic modulus of the housing 62. As a result, according to this embodiment, the hardness of the first positioning member 84 and the second positioning member 88 can be sufficiently increased, and the positioning performance of the inkjet head 46 relative to the carriage 44 can be improved.

[0051] The configuration of an inkjet head 46A according to Modification 1 of this embodiment will be described with reference to Figures 9 and 10. Figures 9 and 10 are schematic bottom views of the inkjet head 46A according to Modification 1 of this embodiment. For ease of explanation, members having the same functions as those described in this embodiment are denoted by the same reference numerals, and their explanation will not be repeated.

[0052] 9 and 10, in an inkjet head 46A according to the first modification of this embodiment, one of the second recesses 64d of the flange portion 64 is formed continuous with the first recess 64c. One of the first positioning members 84 and one of the second positioning members 88 are made of the same member. Therefore, according to the first modification of this embodiment, it is possible to reduce the number of parts of the inkjet head 46A and simplify the configuration of the inkjet head 46A.

[0053] The configuration of an inkjet head 46B according to the second modification of this embodiment will be described with reference to Fig. 11 and Fig. 12. Fig. 11 is a schematic plan view of the inkjet head 46B according to the second modification of this embodiment. Fig. 12 is a schematic bottom view of the inkjet head 46B according to the second modification of this embodiment. For ease of explanation, the same reference numerals are used to refer to members having the same functions as the members described in this embodiment, and the explanations thereof will not be repeated.

[0054] 11 and 12, in an inkjet head 46B according to the second modification of this embodiment, the first positioning member 84 is provided inside the first recess 64c of the flange portion 64 in a state where it is recessed into the side surface of the flange portion 64. Each second positioning member 88 is provided inside the second recess 64d of the flange portion 64 in a state where it is recessed into the side surface of the flange portion 64. Therefore, according to the second modification of this embodiment, it is possible to prevent the first positioning member 84 and the second positioning member 88 from interfering with an obstacle, thereby improving the handleability of the inkjet head 46B.

[0055] The configuration of an inkjet head 46C according to Modification 3 of this embodiment will be described with reference to Fig. 13. Fig. 13 is a schematic perspective view of an inkjet head 46C according to Modification 3 of this embodiment. For ease of explanation, the same reference numerals are used to refer to members having the same functions as those described in this embodiment, and the explanations thereof will not be repeated.

[0056] 13, in an inkjet head 46C according to the third modification of this embodiment, the first recess 64c of one flange portion 64 opens to the upper surface of the one flange portion 64. The second recess 64d of each flange portion 64 opens to the upper surface of each flange portion 64. Therefore, the first positioning member 84 can be easily attached to the inside of the first recess 64c from the upper surface side of the one flange portion 64, and the second positioning member 88 can be easily attached to the inside of the second recess 64d from the upper surface side of each flange portion 64. As a result, according to the third modification of this embodiment, it is possible to improve the ease of assembly of the inkjet head 46.

[0057] The configuration of an inkjet head 46D according to Modification 4 of this embodiment will be described with reference to Fig. 14. Fig. 14 is a schematic perspective view of an inkjet head 46D according to Modification 4 of this embodiment. For ease of explanation, the same reference numerals are used to refer to members having the same functions as those described in this embodiment, and the explanations thereof will not be repeated.

[0058] 14, in an inkjet head 46D according to the fourth modification of this embodiment, the first recess 64c of one flange portion 64 is open to the upper and lower surfaces of the one flange portion 64. The second recess 64d of each flange portion 64 is open to the upper and lower surfaces of each flange portion 64. Therefore, the first positioning member 84 can be easily attached to the inside of the first recess 64c from the upper and lower surfaces of the one flange portion 64, and the second positioning member 88 can be easily attached to the inside of the second recess 64d from the upper and lower surfaces of each flange portion 64. As a result, according to the fourth modification of this embodiment, the ease of assembly of the inkjet head 46 can be further improved.

[0059] Although the present embodiment has been specifically described above, the present invention is not limited to the specific embodiment described above. Various modifications and changes can be made to the specific example described in the above embodiment within the scope of the gist of the present invention described in the claims. [Industrial Applicability]

[0060] INDUSTRIAL APPLICABILITY The present invention is useful as an inkjet head and an inkjet recording apparatus that can improve the heat dissipation of the inkjet head while stably ensuring the positioning accuracy of the inkjet head with respect to the mounting base. [Explanation of symbols]

[0061] 10 Inkjet recording device 12. Device body 14 Center Frame 16 First side frame 18 Second side frame 20 Paper feed section 22 Paper feed tray 24 Conveyor 26 Support Roller 28 Belt 30 Image forming section 32 Image forming drum 34 Delivery Unit 36 Swingarm 38 Delivery Drum 40 Medium heating section 42 Head Unit 44 Carriage (mounting base) 44h through hole 46 Inkjet head 48 Fixing section 50 Delivery Department 52 Support roller 54 Belt 56 Delivery Drum 58 Paper output section 60 Output tray 62 Case 64 Flange part (mounting part) 64c First recess 64d Second recess 64h Through hole 66 Mounting bolt 68 Cover member 70 Manifold 72 Supply Port 74 Exhaust port 76 Head Chip 76n Nozzle 78 Supporting member 80 Wiring board 82 Heater 84 First positioning member 84f First positioning surface 86 First reference member 88 Second positioning member 88f Second positioning surface 90 Second Reference Member 46A Inkjet head (Inkjet head according to modification 1) 46B Inkjet head (Inkjet head according to modification 2) 46C Inkjet head (Inkjet head according to modification 3) 46D Inkjet head (Inkjet head according to modification 4) P Recording medium

Claims

1. a housing having a mounting portion that is placed on an edge of a through hole of a mounting base and attached to the housing; a nozzle provided on a bottom side of the housing for ejecting ink; a positioning member for positioning the housing, the positioning member being located between a contact surface of the housing with the mounting base and an opposing surface of the contact surface, the positioning member being capable of coming into contact with a reference member provided on the mounting base so as to serve as a reference for positioning the housing, The thermal conductivity of the housing is greater than the thermal conductivity of the positioning member, and the thermal expansion coefficient of the positioning member is smaller than the thermal expansion coefficient of the housing. Inkjet head.

2. The positioning member is a first positioning member that is capable of coming into contact with a first reference member that is provided on the mounting base so as to serve as a reference for positioning the housing in the main scanning direction, and that is used to position the housing in the main scanning direction; a second positioning member that is capable of coming into contact with a second reference member provided on the mounting base so as to serve as a reference for positioning the housing in the sub-scanning direction, and that is used to position the housing in the sub-scanning direction; 2. The ink-jet head according to claim 1.

3. The ink jet head according to claim 1 , wherein the positioning member is provided on the mounting portion.

4. The volume of the housing is larger than the volume of the positioning member.

2. The ink-jet head according to claim 1.

5. The positioning member is disposed on a contact surface side of the housing that comes into contact with the mounting base.

2. The ink-jet head according to claim 1.

6. the number of the first positioning members is one or more, and the number of the second positioning members is two or more; one or more of the first positioning members have one or more first positioning surfaces that can abut against the first reference member, and two or more of the second positioning members have two or more second positioning surfaces that can abut against the second reference member, 3. The ink-jet head according to claim 2.

7. The number of the first positioning members is one, and the number of the second positioning members is two, One of the first positioning members has one of the first positioning surfaces, and the two second positioning members each have one of the second positioning surfaces, and the one of the first positioning members and one of the second positioning members are made of the same material.

3. The ink-jet head according to claim 2.

8. A recess is formed on a side surface of the mounting portion, The positioning member is provided inside the recess so as to be recessed into the side surface of the mounting portion.

2. The ink-jet head according to claim 1.

9. A recess is formed on a side surface of the mounting portion, and the recess is open to an upper surface or a lower surface of the mounting portion, The positioning member is provided inside the recess.

2. The ink-jet head according to claim 1.

10. A recess is formed on a side surface of the mounting portion, and the recess is open to an upper and lower surfaces of the mounting portion, The positioning member is provided inside the recess.

2. The ink-jet head according to claim 1.

11. In a temperature environment of 20° C. or higher and 100° C. or lower, the linear expansion coefficient of the housing is 18×10 －６ The linear expansion coefficient of the positioning member is 18×10 －６ is less than 2. The ink-jet head according to claim 1.

12. Further comprising a heater for heating the ink.

2. The ink-jet head according to claim 1.

13. The inkjet head according to claim 12, wherein the heater is provided inside the housing.

14. The thermal conductivity of the housing is lower than the thermal conductivity of the mounting base.

2. The ink-jet head according to claim 1.

15. a head chip provided in the housing and having the nozzle; 2. The ink-jet head according to claim 1.

16. A box-shaped cover member provided on an upper side of the mounting portion; a wiring board provided within the cover member for causing the nozzles to perform a discharge operation; 2. The ink-jet head according to claim 1.

17. The elastic modulus of the positioning member is greater than the elastic modulus of the housing.

2. The ink-jet head according to claim 1.

18. The inkjet head according to any one of claims 1 to 17, Inkjet recording device.

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