阅读说明：本技术 喷墨头以及喷墨记录装置 (Ink jet head and ink jet recording apparatus ) 是由 丸林纯 于 2018-09-07 设计创作，主要内容包括：本发明提供能够有效地抑制由驱动基板的热引起的图像品质降低的喷墨头以及喷墨记录装置。喷墨头具备：墨喷出部,所述墨喷出部在墨喷出面设置有喷出墨的喷嘴的开口部,并具有进行用于从喷嘴的开口部喷出墨的动作的动作元件；驱动基板,所述驱动基板设置有用于驱动动作元件的驱动电路；以及墨盒,所述墨盒储存向墨喷出部供给的墨,墨盒以该墨盒的外表面中的规定的面沿着驱动基板设置且驱动基板的热传递到规定的面的方式设置。(The invention provides an ink jet head and an ink jet recording apparatus capable of effectively suppressing image quality reduction caused by heat of a driving substrate. The ink jet head includes: an ink ejecting section having an opening of a nozzle for ejecting ink on an ink ejecting surface and having an operating element for performing an operation for ejecting ink from the opening of the nozzle; a drive substrate provided with a drive circuit for driving an operation element; and an ink cartridge that stores ink to be supplied to the ink ejection portion, the ink cartridge being provided such that a predetermined surface of an outer surface of the ink cartridge is provided along the drive substrate and heat of the drive substrate is transferred to the predetermined surface.)

1. An ink jet head, comprising:

an ink ejecting section having an opening of a nozzle for ejecting ink on an ink ejecting surface and having an operating element for performing an operation for ejecting ink from the opening of the nozzle;

a drive substrate provided with a drive circuit for driving the action element; and

an ink cartridge storing ink supplied to the ink ejection portion,

the ink cartridge is provided such that a predetermined surface of an outer surface of the ink cartridge is provided along the drive substrate and heat of the drive substrate is transferred to the predetermined surface.

2. The ink jet head according to claim 1, wherein,

the drive substrate is provided on a side of the ink ejection portion opposite to the ink ejection surface in a direction intersecting the ink ejection surface.

3. An ink jet head according to claim 1 or 2,

the ink cartridge is provided with:

an in-cartridge flow path through which the ink supplied to the ink ejection unit flows in a predetermined supply direction; and

a first filter provided along the predetermined surface inside the flow path in the cartridge and through which ink flowing in the flow path in the cartridge passes.

4. An ink jet head according to claim 3,

the flow path in the cartridge includes:

an upstream-side ink chamber adjacent to an upstream side of the first filter in the feeding direction; and

a downstream-side ink chamber adjacent to a downstream side of the first filter in the feeding direction,

the upstream ink chamber is provided on the predetermined surface side of the first filter.

5. An ink jet head according to claim 3,

the flow path in the cartridge includes:

an upstream-side ink chamber adjacent to an upstream side of the first filter in the feeding direction; and

a downstream-side ink chamber adjacent to a downstream side of the first filter in the feeding direction,

the downstream ink chamber is provided on the predetermined surface side of the first filter.

6. An ink jet head according to any of claims 3 to 5,

the ink ejection portion has an outlet port through which a part of the ink flowing from the flow path in the cartridge flows out,

the inkjet head includes an ink discharge channel for guiding the ink flowing out from the outlet of the ink discharge unit to the outside of the inkjet head.

7. The ink jet head according to claim 6, wherein,

the ink jet head includes:

a bypass flow path that connects the cartridge flow path and the ink discharge flow path without passing through the ink ejection section;

a second filter provided inside the bypass flow path, through which ink flowing in the bypass flow path passes; and

a backflow prevention member that is provided between a connection position in the ink discharge flow path that is connected to the bypass flow path and an outlet of the ink discharge flow path, and that does not pass ink in a direction opposite to a direction toward the outlet.

8. The ink jet head according to claim 7, wherein,

the bypass flow path is provided inside the ink cartridge,

the first filter and the second filter are integrally provided.

9. An ink jet head according to any of claims 3 to 8,

the ink jet head includes a mounting member that detachably fixes the ink cartridge.

10. An ink jet head according to any of claims 1 to 9,

a cover member that covers at least a part of the drive substrate is provided between the ink cartridge and the drive substrate,

a heat radiating member that is in contact with the cover member and the ink cartridge is provided between the cover member and the ink cartridge.

11. An ink jet head according to any of claims 1 to 10,

the heat dissipation amount of the heat dissipation from one surface of the driving substrate is larger than the heat dissipation amount of the heat dissipation from the other surface of the driving substrate when the driving circuit operates,

the ink cartridge is disposed on the one surface side of the drive substrate.

12. An inkjet recording apparatus, comprising the inkjet head according to any one of claims 1 to 11.

Technical Field

The invention relates to an ink jet head and an ink jet recording apparatus.

Background

Conventionally, there is an ink jet recording apparatus that forms an image by ejecting ink from an opening of a nozzle provided on an ink ejection surface of an ink jet head and landing the ink at a desired position. An ink jet head of an ink jet recording apparatus includes an ink ejecting section that ejects ink from an opening of a nozzle in accordance with an operation of an operating element such as a piezoelectric element that varies a pressure in an ink storing section communicating with the nozzle. In addition, the ink jet head generally includes a drive substrate provided with a drive circuit for driving the operation element (for example, patent document 1).

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2014-004767

Disclosure of Invention

Problems to be solved by the invention

However, when the temperature of the drive substrate rises due to the operating heat of the drive circuit, the heat of the drive substrate is transferred to the ink in the ink ejection portion to lower the viscosity of the ink, so that proper ink ejection is not performed, or the ink ejection portion expands due to the heat of the drive substrate to change the position of the nozzle, thereby degrading the image quality of the recorded image.

The invention aims to provide an ink jet head and an ink jet recording apparatus capable of effectively inhibiting image quality reduction caused by heat of a driving substrate.

Means for solving the problems

In order to achieve the above object, according to the invention, as set forth in claim 1, there is provided an ink jet head comprising:

an ink ejecting section having an opening of a nozzle for ejecting ink on an ink ejecting surface and having an operating element for performing an operation for ejecting ink from the opening of the nozzle;

a drive substrate provided with a drive circuit for driving the action element; and

an ink cartridge storing ink supplied to the ink ejection portion,

the ink cartridge is provided such that a predetermined surface of an outer surface of the ink cartridge is provided along the drive substrate and heat of the drive substrate is transferred to the predetermined surface.

The invention described in claim 2 is the ink jet head described in claim 1,

the drive substrate is provided on a side of the ink ejection portion opposite to the ink ejection surface in a direction intersecting the ink ejection surface.

The invention described in claim 3 is the ink jet head described in claim 1 or 2,

the ink cartridge is provided with:

an in-cartridge flow path through which the ink supplied to the ink ejection unit flows in a predetermined supply direction; and

a first filter provided along the predetermined surface inside the flow path in the cartridge and through which ink flowing in the flow path in the cartridge passes.

The invention described in claim 4 is the ink jet head described in claim 3,

the flow path in the cartridge includes:

an upstream-side ink chamber adjacent to an upstream side of the first filter in the feeding direction; and

a downstream-side ink chamber adjacent to a downstream side of the first filter in the feeding direction,

the upstream ink chamber is provided on the predetermined surface side of the first filter.

The invention described in claim 5 is the ink jet head described in claim 3,

the flow path in the cartridge includes:

an upstream-side ink chamber adjacent to an upstream side of the first filter in the feeding direction; and

a downstream-side ink chamber adjacent to a downstream side of the first filter in the feeding direction,

the downstream ink chamber is provided on the predetermined surface side of the first filter.

The invention described in claim 6 provides the ink jet head described in any one of claims 3 to 5,

the ink ejection portion has an outlet port through which a part of the ink flowing from the flow path in the cartridge flows out,

the inkjet head includes an ink discharge channel for guiding the ink flowing out from the outlet of the ink discharge unit to the outside of the inkjet head.

The invention described in claim 7 is the ink jet head described in claim 6,

the ink jet head includes:

a bypass flow path that connects the cartridge flow path and the ink discharge flow path without passing through the ink ejection section;

a second filter provided inside the bypass flow path, through which ink flowing in the bypass flow path passes; and

a backflow prevention member that is provided between a connection position in the ink discharge flow path that is connected to the bypass flow path and an outlet of the ink discharge flow path, and that does not pass ink in a direction opposite to a direction toward the outlet.

The invention described in claim 8 is the ink jet head described in claim 7,

the bypass flow path is provided inside the ink cartridge,

the first filter and the second filter are integrally provided.

The invention described in claim 9 provides the ink jet head described in any one of claims 3 to 8,

the ink jet head includes a mounting member that detachably fixes the ink cartridge.

The invention described in claim 10 provides the ink jet head described in any one of claims 1 to 9,

a cover member that covers at least a part of the drive substrate is provided between the ink cartridge and the drive substrate,

a heat radiating member that is in contact with the cover member and the ink cartridge is provided between the cover member and the ink cartridge.

The invention described in claim 11 provides the ink jet head according to any one of claims 1 to 10,

the heat dissipation amount of the heat dissipation from one surface of the driving substrate is larger than the heat dissipation amount of the heat dissipation from the other surface of the driving substrate when the driving circuit operates,

the ink cartridge is disposed on the one surface side of the drive substrate.

In order to achieve the above object, the invention of an inkjet recording apparatus according to claim 12 includes the inkjet head according to any one of claims 1 to 11.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present invention, it is possible to effectively suppress the deterioration of image quality due to the heat of the driving substrate.

Drawings

Fig. 1 is a schematic configuration diagram of an inkjet recording apparatus.

Fig. 2 is a schematic diagram showing the structure of the inkjet head unit.

Fig. 3 is a perspective view of the ink jet head.

Fig. 4 is a view showing a cross section of the inkjet head along the YZ plane.

Fig. 5 is an enlarged schematic cross-sectional view showing a structure of the ink ejection portion.

Fig. 6 is a view showing a cross section of the inkjet head along the XY plane.

Fig. 7 is a perspective view of an ink jet head showing an internal structure of the ink cartridge.

Fig. 8A is a view showing a cross section of the ink cartridge along the YZ plane at the position X1 in fig. 7.

Fig. 8B is a view showing a cross section of the ink cartridge along the YZ plane at the position X2 in fig. 7.

Fig. 8C is a view showing a cross section of the ink cartridge along the YZ plane at the position X3 in fig. 7.

Fig. 9 is a schematic diagram illustrating a flow path of ink in the inkjet head.

Fig. 10 is a schematic diagram showing the structure of the ink circulation mechanism.

Fig. 11 is a block diagram showing a main functional configuration of the inkjet recording apparatus.

Fig. 12 is a diagram showing the flow direction of ink in the downstream-side ink chamber of the modification.

Detailed Description

Hereinafter, embodiments of an ink jet head and an ink jet recording apparatus according to the present invention will be described with reference to the drawings.

Fig. 1 is a diagram showing a schematic configuration of an inkjet recording apparatus 1 according to an embodiment of the present invention.

The inkjet recording apparatus 1 includes a transport unit 2, an inkjet head unit 3, and the like.

The conveying unit 2 includes an endless conveyor belt 2c supported by 2 conveying rollers 2a and 2b that rotate about a rotation axis extending in the X direction in fig. 1. In a state where the recording medium M is placed on the conveying surface of the conveyor belt 2c, the conveyor belt 2c is moved around by the rotation of the conveyor roller 2a in accordance with the operation of a conveyor motor (not shown), and the recording medium M is conveyed in the moving direction (conveying direction; Y direction in fig. 1) of the conveyor belt 2 c.

The recording medium M may be a single sheet of paper cut to a certain size. The recording medium M is fed onto the transport belt 2c by a paper feeding device, not shown, and is discharged from the transport belt 2c to a predetermined paper discharge unit after an image is recorded by ejecting ink from the inkjet head unit 3. Note that roll paper may be used as the recording medium M. As the recording medium M, various media capable of fixing the ink landed on the surface, such as cloth, sheet-like resin, and the like, may be used in addition to paper such as plain paper and coated paper.

The inkjet head unit 3 ejects ink to the recording medium M conveyed by the conveying portion 2 at an appropriate timing based on the image data to record an image. In the inkjet recording apparatus 1 of the present embodiment, the four inkjet head units 3 corresponding to the four colors of yellow (Y), magenta (M), cyan (C), and black (K) are arranged at predetermined intervals in the order of Y, M, C, K colors from the upstream side in the conveying direction of the recording medium M. The number of the ink jet head units 3 may be three or less or five or more.

Fig. 2 is a schematic diagram showing the structure of the inkjet head unit 3, and is a plan view of the inkjet head unit 3 as viewed from the side opposite to the conveying surface of the conveyor belt 2 c. The ink jet head unit 3 includes: a plate-like support portion 3a, and a plurality of (eight in this case) ink jet heads 100 fixed to the support portion 3a in a state of being fitted in through holes provided in the support portion 3 a. The inkjet head 100 is fixed to the support 3a in a state where an ink ejection surface 112 provided with openings of the nozzles 111 is exposed in the-Z direction from through holes of the support 3 a.

In the inkjet head 100, the plurality of nozzles 111 are arranged at equal intervals in a direction intersecting the conveyance direction of the recording medium M (in the present embodiment, in the X direction, which is a width direction orthogonal to the conveyance direction). In the present embodiment, each inkjet head 100 has four rows (nozzle rows) of nozzles 111 arranged one-dimensionally at equal intervals in the X direction. The four nozzle rows are arranged so as to be shifted from each other in the X direction so that the positions of the nozzles 111 in the X direction do not overlap. The number of nozzle rows included in the inkjet head 100 is not limited to four, and may be three or less, or five or more.

The eight inkjet heads 100 in the inkjet head unit 3 are arranged in a staggered grid pattern so that the arrangement range of the nozzles 111 in the X direction is continuous. The arrangement range of the nozzles 111 included in the inkjet head unit 3 in the X direction covers the width of the region in the X direction in which an image can be recorded in the recording medium M conveyed by the conveyor belt 2 c. The inkjet head unit 3 is used with its position fixed at the time of recording an image, and ejects ink from the nozzles 111 to each position at a predetermined interval in the conveyance direction (conveyance direction interval) in accordance with conveyance of the recording medium M, thereby recording an image in a single-pass manner.

Fig. 3 is a perspective view of the inkjet head 100.

The inkjet head 100 includes: an exterior member 51 which accommodates therein an ink ejecting section 10 (fig. 4) having an ink ejecting surface 112; a cover member 52 fitted to the exterior member 51 at the upper end of the exterior member 51; an ink cartridge 60 mounted at a position covering a part of the outer side of the cover member 52; an inlet 71 (ink supply port) to which ink is supplied from the outside; and an outlet 72 (ink discharge port) for discharging ink to the outside.

The exterior member 51 includes: an orifice (origin) 511 (fig. 7) into which ink supplied to the inflow port 101 (fig. 9) of ink of the ink ejection portion 10 flows; and an orifice 512 (fig. 7) through which ink flowing out from the outflow port 102 (fig. 9) of the ink ejection portion 10 is discharged. Further, the exterior member 51 is provided with a plurality of mounting holes 513 for mounting the inkjet head 100 to the support portion 3a of the inkjet head unit 3.

The materials of the exterior member 51 and the cover member 52 are not particularly limited, and various resins, such as PPS resin, which is excellent in mechanical strength and chemical resistance to ink, metals, alloys, and the like can be used.

The inlet 71 and the outlet 72 are provided at both ends of the cover member 52 in the longitudinal direction. That is, the inlet 71 is provided on the + X direction side of the cover member 52, and the outlet 72 is provided on the-X direction side of the cover member 52.

The ink cartridge 60 has one end connected to the inlet 71 and the other end connected to the outlet 72, stores ink flowing from the inlet 71, and supplies the ink to the ink ejecting portion 10 in the exterior member 51. The ink cartridge 60 is provided such that a flat plate-like portion (a portion in which ink is mainly stored) connecting the one end side and the other end side covers an upper half portion of a front surface (a surface facing the + Y direction side) of the cover member 52.

The ink cartridge 60 includes: a cover 602 that constitutes the front side (+ Y direction side) of the flat plate-like portion; a base 601 facing the cover 602; and fixing portions 603 extending downward from both ends of the base portion 601 in the X direction and fixed to the exterior member 51. The fixing portion 603 is detachably fixed to the exterior member 51 by a plurality of mounting screws 54 (mounting members). That is, the ink cartridge 60 can be removed from the inkjet head 100 and replaced.

Fig. 4 is a view showing a cross section of the inkjet head 100 of fig. 3 along the YZ plane.

As shown in fig. 4, the ink ejection portion 10 whose lower surface serves as the ink ejection surface 112, the wiring member 40 connected to the ink ejection portion 10, the drive substrate 30 to which the wiring member 40 is connected, and the like are housed in the internal space formed by the exterior member 51 and the cover member 52.

Further, a step is provided on the front surface of the cover member 52 so that the upper half of the surface is shifted to the-Y direction side from the lower half, and the ink cartridge 60 is mounted so as to be accommodated in the step. Specifically, the ink cartridge 60 is disposed so as to be accommodated in a range on the-Y direction side with respect to a plane defined by a lower half portion of the front surface of the cover member 52. With such a configuration, the ink cartridge 60 can be provided without increasing the width of the inkjet head 100 in the Y direction.

The drive substrate 30 is provided on the opposite side of the ink ejection surface 112 of the ink ejection portion 10 (i.e., on the + Z direction side), along a direction intersecting the ink ejection surface 112 of the ink ejection portion 10 (in the present embodiment, a vertical direction perpendicular to the ink ejection surface 112, i.e., the + Z direction). In detail, the drive board 30 is fixed in the relative position with respect to the cover member 52 by a fixing member, not shown, so as to be arranged in such an orientation and position. The drive substrate 30 is disposed so that a portion other than a portion at the upper end is covered with the cover member 52.

The drive substrate 30 is a rigid substrate having a metal circuit wiring formed on the surface of an insulating base material such as a glass epoxy substrate. The drive substrate 30 may be flexible within a range in which it can be stably fixed to the cover member 52.

The ink ejection portion 10 includes: a nozzle substrate 11 (nozzle plate) provided with nozzles 111 and constituting an ink ejection surface 112; an actuator substrate 12 which is stacked on the + Z direction side of the nozzle substrate 11 and is provided with an actuator (an operating element) which performs an operation for ejecting ink from an opening of the nozzle 111; and a common ink chamber 13 (common liquid chamber) that temporarily stores ink supplied to the actuator substrate 12. Ink flows from the ink cartridge 60 into the common ink chamber 13 via the orifice 511.

Fig. 5 is an enlarged schematic cross-sectional view showing the structure of the ink ejection section 10. In fig. 5, a cross section including four nozzles 111 included in the four nozzle rows shown in fig. 2, respectively, is shown.

The head chip HC including the nozzle substrate 11 and the actuator substrate 12 is configured to eject ink from the nozzles 111, and a plurality of, here, four plate-shaped substrates are stacked. The lowermost substrate in the head chip HC is the nozzle substrate 11. The nozzle substrate 11 is provided with a plurality of nozzles 111, and ink can be ejected from openings of the nozzles 111 substantially perpendicular to an exposed surface (ink ejection surface 112) of the nozzle substrate 11. A pressure chamber substrate 12a (chamber plate), a spacer substrate 12b, and a wiring forming substrate 12c are bonded and laminated in this order upward on the side of the nozzle substrate 11 opposite to the ink ejection surface 112. The actuator substrate 12 is configured by a pressure chamber substrate 12a, a spacer substrate 12b, and a wiring forming substrate 12 c.

The head chip HC is provided with an ink flow path communicating with the nozzle 111, and is opened on the surface of the wiring forming substrate 12c on the exposed side (upper side). A common ink chamber 13 is provided on the exposed surface of the wiring forming substrate 12c so as to cover all the openings. In detail, the common ink chamber 13 has a first common ink chamber 131 and a second common ink chamber 132 provided at a lower layer (-Z direction side) of the first common ink chamber 131, wherein the second common ink chamber 132 communicates commonly with all the openings of the ink flow paths. The ink in the second common ink chamber 132 is supplied from the opening of the wiring forming substrate 12c to each nozzle 111.

A pressure chamber 121 is provided in the ink flow path. The pressure chamber 121 is provided to penetrate the pressure chamber substrate 12a in the vertical direction, and the upper surface of the pressure chamber 121 is formed by a vibration plate 122 provided between the pressure chamber substrate 12a and the partition substrate 12 b. The vibration plate 122 (pressure chamber 121) is deformed by displacement (deformation) of the piezoelectric element 123 (actuator, operation element) in the housing 124 provided adjacent to the pressure chamber 121 via the vibration plate 122, and a pressure change is applied to the ink in the pressure chamber 121. By applying an appropriate pressure change to the ink in the pressure chamber 121, the ink in the ink channel is ejected as droplets from the nozzle 111 communicating with the pressure chamber 121.

The holding substrate 133 is bonded to the upper surface of the head chip HC, and holds the common ink chamber 13. The holding substrate 133 is provided with an opening having substantially the same size and shape as the opening of the lower surface of the second common ink chamber 132, and the ink in the second common ink chamber 132 is supplied to the upper surface of the head chip HC through the opening of the lower surface of the second common ink chamber 132 and the opening of the holding substrate 133.

The wiring member 40 is, for example, an FPC (Flexible Printed circuit), and is connected to the wiring layer 127 on the surface of the wiring substrate 12 c. The piezoelectric element 123 is displaced by a drive signal transmitted to the wiring 126 and the connection portion 125 in the housing portion 124 through the wiring layer 127. The wiring members 40 are led out from the front side (+ Y direction side) and the rear side (-Y direction side) of the head chip HC through the holding substrate 133 one by one. As shown in fig. 4, the pair of wiring members 40 are connected to the circuit wiring on the front surface and the circuit wiring on the rear surface of the drive substrate 30 via first connectors 32 provided on the surface on the + Y direction side (hereinafter also referred to as the front surface) and the surface on the-Y direction side (hereinafter also referred to as the rear surface) of the drive substrate 30, respectively.

As shown in fig. 4, on the front surface of the drive substrate 30, a drive element 31, a second connector 33, and the like are mounted in addition to the first connector 32.

The driving element 31 receives control signals supplied from the control unit 20 (fig. 11) of the inkjet recording apparatus 1 and the drive control circuit 81 (fig. 11) of the inkjet head unit 3 via the second connector 33, and outputs appropriate drive signals for the piezoelectric element 123 to the wiring on the driving substrate 30 in accordance with the ink ejection operation and the non-ejection operation from the nozzles 111. The drive element 31 is formed of an IC (Integrated Circuit) or the like. In addition to the drive element 31, various electronic components not shown, which are directly or indirectly connected to the drive element 31 through circuit wiring, are mounted on the drive substrate 30. These electronic components and the driving element 31 constitute a "driving circuit" for driving the piezoelectric element 123 as an operating element.

Most of the driving elements 31 and electronic components constituting the driving circuit are mounted on the front surface of the driving substrate 30. A part of the drive signal from the drive circuit is supplied to the first connector 32 on the front surface side via circuit wiring provided on the front surface of the drive substrate 30. Further, a part of the front-side circuit wiring is electrically connected to the back-side circuit wiring via a through hole or the like, and a part of a drive signal from the drive circuit is supplied to the back-side first connector 32 via the back-side circuit wiring.

Further, by mounting the driving element 31 and most of the electronic components on the front surface of the driving board 30, the amount of heat radiated from the front surface of the driving board 30 when the driving circuit operates is larger than the amount of heat radiated from the rear surface.

Fig. 6 is a view showing a cross section along the XY plane at a position where the inkjet head 100 passes through the driving element 31.

As shown in fig. 6, the cover member 52 has: a planar portion 521 provided along and facing the front surface of the drive substrate 30; a planar portion 522 facing and disposed along the rear surface of the drive substrate 30; and a side surface portion 523 that connects the planar portions 521 and 522 to cover a lateral side of the drive board 30, and the cover member 52 covers most of the drive board 30 except for a portion near the second connector 33.

As shown in fig. 4 and 6, the ink cartridge 60 is provided along a flat surface portion 521 of the cover member 52 that covers the front surface side of the drive substrate 30. That is, the ink cartridge 60 is provided along the drive substrate 30 with an opposing surface 60a (surface facing in the-Y direction) (predetermined surface) of the outer surface of the ink cartridge 60 that opposes the cover member 52.

Further, a sheet-shaped heat radiating member 53 that contacts the ink cartridge 60 and the cover member 52 is provided between the facing surface 60a of the ink cartridge 60 and the flat surface portion 521 of the cover member 52. As the heat radiating member 53, any member having a thermal conductivity higher than that of air can be used, but a member having a high thermal conductivity such as silicone or acrylic is preferably used so that heat is efficiently transmitted from the cover member 52 to the ink cartridge 60.

In this way, the ink cartridge 60 is provided so that heat radiated from the drive substrate 30 is transmitted to the facing surface 60a via the cover member 52 and the heat radiating member 53. That is, the ink cartridge 60 also functions as a heat sink that receives heat from the drive substrate 30 and discharges the heat to the outside. A part of the heat transmitted from the drive board 30 to the ink cartridge 60 is discharged from the outer surface of the ink cartridge 60 to the external space, and is discharged from the ink cartridge 60 to the support portion 3a of the inkjet head unit 3 via the exterior member 51. Further, a part of the heat transferred to the ink cartridge 60 is transferred to the ink in the ink cartridge 60, and is discharged from the outlet 72 together with the ink through an ink flow path described later.

As shown in fig. 6, a cylindrical through hole extending in the + Z direction is provided in the end portion on the + X direction side of the base 601 of the ink cartridge 60, and the through hole constitutes an ink supply channel 711. One end of the ink supply channel 711 is connected to the inlet 71, and the other end is connected to an opening a1 (fig. 7) described later.

On the other hand, a cylindrical through hole extending in the + Z direction is provided in the base 601 of the ink cartridge 60 at the end on the-X direction side, and this through hole constitutes an ink discharge flow path 721. One end of the ink discharge channel 721 is connected to the orifice 512 of the exterior member 51, and the other end is connected to the outlet 72.

Here, the internal structure of the ink cartridge 60 and the flow path of the ink in the internal structure will be described with reference to fig. 4, 6, 7, and 8A to 8C.

Fig. 7 is a perspective view of the inkjet head 100 showing the internal structure of the ink cartridge 60. In fig. 7, the components constituting the outer surface of the ink cartridge 60 are depicted as being transparent.

Fig. 8A is a view showing a cross section of the ink cartridge 60 along the YZ plane at the position X1 in fig. 7.

Fig. 8B is a view showing a cross section of the ink cartridge 60 along the YZ plane at the position X2 in fig. 7.

Fig. 8C is a view showing a cross section of the ink cartridge 60 along the YZ plane at the position X3 in fig. 7.

In fig. 7 and 8A to 8C, the flow direction of ink is indicated by an arrow.

Inside the ink cartridge 60, there are provided: a flat plate-like filter 61 (first filter, second filter) provided along the facing surface 60 a; an upstream-side ink chamber 62 and a downstream-side ink chamber 63 partitioned by a filter 61; a bypass flow path 64 communicating with the downstream side ink chamber 63; an upstream side auxiliary ink chamber 65 and a downstream side auxiliary ink chamber 66 partitioned by a filter 61 (second filter); a communication flow path 67 communicating with the downstream side auxiliary ink chamber 66; an ink supply flow path 711 (fig. 6) communicating with the inlet 71; and an ink discharge flow path 721 communicating with the outlet 72, and the like.

As shown in fig. 4, 6, 7, and 8A, the upstream ink chamber 62 and the downstream ink chamber 63 are ink chambers in a flat substantially rectangular parallelepiped shape along the facing surface 60a, and ink can move from the upstream ink chamber 62 to the downstream ink chamber 63 via a filter 61 provided between the upstream ink chamber 62 and the downstream ink chamber 63. The upstream ink chamber 62 is provided adjacent to the-Y direction side (facing surface 60a side) of the filter 61, and the downstream ink chamber 63 is provided adjacent to the + Y direction side of the filter 61.

The filter 61 is a member for capturing foreign matter mixed in the ink and filtering the ink. The material of the filter 61 is not particularly limited as long as it has a mesh structure having a size capable of capturing foreign matter, and for example, a member woven with stainless steel, a nonwoven fabric formed of resin fibers such as polypropylene, or the like can be used.

A portion of the filter 61 disposed between the upstream-side ink chamber 62 and the downstream-side ink chamber 63 constitutes a "first filter".

As shown in fig. 7, an opening a1 communicating with the ink supply flow path 711 is provided at the lower end of the + X direction side surface of the upstream ink chamber 62. Ink flows from the inlet 71 into the upstream side ink chamber 62 via the ink supply flow path 711 and the opening a 1.

As shown in fig. 7 and 8B, an opening a2 that communicates with the bypass flow path 64 is provided at the-X direction side end of the upper surface (+ Z direction side surface) of the downstream side ink chamber 63.

In the upstream side ink chamber 62 and the downstream side ink chamber 63, as indicated by an arrow a1 in fig. 7, 8A, and 8B, ink moves from the upstream side ink chamber 62 to the downstream side ink chamber 63 through the filter 61, and flows in the-X direction and the + Z direction from the opening a1 toward the opening a 2.

As shown in fig. 7, 8A, and 8B, the bypass flow path 64 includes: a first portion extending in the + X direction at the upper portions of the upstream ink chamber 62 and the downstream ink chamber 63; and a second portion extending in a downward direction (-Z direction) from an end portion of the first portion on the + X direction side of the upstream ink chamber 62 and the downstream ink chamber 63, the end portion of the second portion being connected to an orifice 511 provided in the exterior member 51. The orifice 511 communicates with the common ink chamber 13 of the ink ejection portion 10. In this way, the bypass flow path 64 bypasses the ink flowing from the downstream ink chamber 63 in the + X direction (arrow a2 in fig. 7, 8A, and 8B) and the-Z direction and guides the ink to the orifice 511.

The upstream ink chamber 62, the downstream ink chamber 63, and the bypass passage 64 described above constitute an "in-cartridge passage F1" (fig. 9). The ink flow direction from the upstream ink chamber 62 to the downstream ink chamber 63, and to the orifice 511 via the bypass flow path 64 in the cartridge flow path F1 corresponds to the "predetermined supply direction".

As shown in fig. 7, an upstream side auxiliary ink chamber 65 and a downstream side auxiliary ink chamber 66 are provided on the-X direction side of the upstream side ink chamber 62 and the downstream side ink chamber 63. The upstream auxiliary ink chamber 65 and the downstream auxiliary ink chamber 66 are ink chambers in a flat substantially rectangular parallelepiped shape along the facing surface 60a, have the same thickness (length in the Y direction) and height (length in the Z direction) as the upstream ink chamber 62 and the downstream ink chamber 63, and have a smaller width (length in the X direction) than the upstream ink chamber 62 and the downstream ink chamber 63. The upstream side auxiliary ink chamber 65 is partitioned from the upstream side ink chamber 62 by a first partition member 681 provided integrally with the base 601, and the downstream side auxiliary ink chamber 66 is partitioned from the downstream side ink chamber 63 by a second partition member 682 provided integrally with the cover 602.

As shown in fig. 7 and 8C, an opening a3 is provided at the upper end of the first partitioning member 681. Therefore, a part of the ink that has flowed into the upstream ink chamber 62 before moving toward the downstream ink chamber 63 flows into the upstream auxiliary ink chamber 65 through the opening A3 as indicated by an arrow A3 in fig. 7 and 8C.

The ink that has flowed into the upstream side auxiliary ink chamber 65 moves to the downstream side auxiliary ink chamber 66 through the filter 61.

A portion of the filter 61 disposed between the upstream side auxiliary ink chamber 65 and the downstream side auxiliary ink chamber 66 constitutes a "second filter".

In the present embodiment, the "first filter" and the "second filter" provided between the upstream side ink chamber 62 and the downstream side ink chamber 63 are constituted by a single filter 61. In other words, the "first filter" and the "second filter" are integrally provided.

At an end portion on the-X direction side of the upper surface (+ Z direction side surface) of the downstream side auxiliary ink chamber 66, an opening a4 communicating with the communication flow path 67 is provided.

The communication passage 67 extends from the opening a4 in the + Z direction, is bent in the-X direction, and is arranged in a serpentine shape extending in the-Z direction. An end of the communication flow path 67 on the opposite side of the opening a4 is connected to the ink discharge flow path 721.

Therefore, the ink that has flowed into the upstream side auxiliary ink chamber 65 moves to the downstream side auxiliary ink chamber 66 through the filter 61, and then flows into the ink discharge flow path 721 through the communication flow path 67.

The upstream side auxiliary ink chamber 65, the downstream side auxiliary ink chamber 66, and the communication flow path 67 constitute a "bypass flow path F2" (fig. 9) that connects the in-cartridge flow path F1 and the ink discharge flow path 721 without passing through the ink ejection portion 10.

Further, a check valve 73 (one-way valve) as a backflow prevention member is provided between the outlet 72 and a connection position of the ink discharge flow path 721 with the bypass flow path F2, and the check valve 73 allows ink to pass in a discharge direction toward the outlet 72, but does not allow ink to pass in a direction opposite to the discharge direction.

Next, a flow path of ink in the entire inkjet head 100 including the ink cartridge 60 will be described.

Fig. 9 is a schematic diagram illustrating a flow path of ink in the inkjet head 100. In fig. 9, for convenience of explanation, the filter 61, the upstream side ink chamber 62, and the downstream side ink chamber 63 in the ink cartridge 60 are drawn in a laterally long shape.

As shown in fig. 9, the ink having flowed into the inlet 71 from the outside flows into the upstream side ink chamber 62 in the ink cartridge 60 through the opening a1 via the ink supply passage 711. Most of the ink flowing into the upstream ink chamber 62 flows into the inlet 101 of the ink ejection unit 10 through the in-cartridge flow path F1.

A part of the ink flowing into the inflow port 101 flows into the first common ink chamber 131 of the common ink chamber 13, and the remaining ink flows into the second common ink chamber 132. The partition wall between the first common ink chamber 131 and the second common ink chamber 132 is made of a member (e.g., resin) through which ink cannot pass.

The ink flowing into the first common ink chamber 131 is directly guided to the outlet port 102 of the ink ejection portion 10.

A part of the ink flowing into the second common ink chamber 132 flows into the ink flow path of the actuator substrate 12 and is discharged as droplets to the outside from the nozzles 111 of the nozzle substrate 11, and the ink not discharged from the nozzles 111 is guided to the outlet port 102.

In this way, ink that is not ejected from the nozzles 111 flows into the first common ink chamber 131 and flows out from the outflow port 102, whereby the ink can be efficiently returned inside the inkjet head 100. This allows bubbles in the ink to be discharged to the outside, or allows heat transferred from the drive substrate 30 to the ink to be discharged to the outside together with the ink.

The volume ratio of the first common ink chamber 131 to the second common ink chamber 132 is set so that the amount of ink returned by the first common ink chamber 131 is a desired amount while ensuring the supply amount of ink from the second common ink chamber 132 to the nozzles 111.

The ink flowing out of the outlet port 102 of the ink ejection portion 10 is discharged to the outside from the outlet 72 (the outlet of the ink discharge flow path 721) through the ink discharge flow path 721.

Further, as described above, a part of the ink flowing in the cartridge flow path F1 flows from the opening A3 into the bypass flow path F2, and is guided to the ink discharge flow path 721 without passing through the ink ejection portion 10.

Further, by providing the check valve 73 between the outlet 72 and the connection position of the bypass flow path F2 in the ink discharge flow path 721, the ink can be prevented from flowing backward from the outlet 72 side to the ink ejection portion 10.

The flow of ink in the flow path of ink shown in fig. 9 can be generated by the ink circulation mechanism 9 provided to the inkjet recording apparatus 1.

Fig. 10 is a schematic diagram showing the structure of the ink circulation mechanism 9.

The ink circulation mechanism 9 includes a supply sub-tank 91, a return sub-tank 92, a main tank 93, and the like.

The supply sub-tank 91 stores ink supplied to the ink cartridges 60 of the inkjet head 100. The supply sub-tank 91 is connected to the inlet 71 through an ink flow path 94.

The return sub-tank 92 is connected to the outlet 72 via an ink channel 95, and stores the ink discharged from the outlet 72.

The supply sub-tank 91 and the return sub-tank 92 are connected by an ink channel 96. Further, the ink can be returned from the sub-tank 92 for return to the sub-tank 91 for supply by the pump 98 provided in the ink flow path 96.

The main tank 93 stores ink supplied to the supply sub tank 91. The main cartridge 93 is connected to the supply sub-cartridge 91 through an ink flow path 97. Further, ink is supplied from the main tank 93 to the supply sub tank 91 by a pump 99 provided in the ink flow path 97.

The liquid surface of the supply subtank 91 is set at a position higher than an ink ejection surface 112 (hereinafter, also referred to as a "position reference surface") of the ink ejection portion 10, and the liquid surface of the return subtank 92 is set at a position lower than the position reference surface. Therefore, a pressure P1 due to a difference in water level between the position reference surface and the supply sub-tank 91 and a pressure P2 due to a difference in water level between the position reference surface and the return sub-tank 92 are generated. As a result, the pressure of the ink at the inlet 71 is higher than the pressure of the ink at the outlet 72. By this pressure difference, a flow of ink from the inlet 71 through the ink cartridge 60 and the ink ejection portion 10 toward the outlet 72 is generated, and ink supply to the ink ejection portion 10 and ink discharge (return) from the ink ejection portion 10 are performed. Further, by changing the amount of ink in each sub-cartridge and the position of each sub-cartridge in the vertical direction, the pressure P1 and the pressure P2 can be adjusted, and the flow rate of ink can be adjusted.

Fig. 11 is a block diagram showing a main functional configuration of the inkjet recording apparatus 1.

The inkjet recording device 1 includes the inkjet head unit 3, the control unit 20, the transport drive unit 82, the input/output interface 83, the bus 84, and the like. Among them, the inkjet head unit 3 has a drive control circuit 81 and the inkjet head 100 provided with the driving element 31 and the piezoelectric element 123. The control Unit 20 includes a CPU21(Central Processing Unit), a RAM22(Random Access Memory), a ROM23(Read Only Memory), and a storage Unit 24.

The CPU21 reads out various control programs and setting data stored in the ROM23 and stores them in the RAM22, and executes the programs to perform various arithmetic processes. The CPU21 comprehensively controls the overall operation of the inkjet recording apparatus 1.

The RAM22 provides the CPU21 with a storage space for work, and stores temporary data. The RAM22 may also include non-volatile memory.

The ROM23 stores programs for various controls, setting data, and the like executed by the CPU 21. Instead of the ROM23, a rewritable nonvolatile Memory such as an EEPROM (Electrically Erasable Programmable Read Only Memory) or a flash Memory may be used.

The storage unit 24 stores a print job input from the external apparatus 200 via the input/output interface 83 and image data relating to the print job. The storage unit 24 may be, for example, an HDD (Hard Disk Drive) or a DRAM (Dynamic Random Access Memory) as well.

The drive control circuit 81 supplies various control signals and image data to the drive element 31 at appropriate timings based on the control signal from the control unit 20.

The conveyance driving unit 82 supplies a driving signal to the motor that drives the conveyance rollers 2a and 2b of the conveyance unit 2 based on a control signal supplied from the CPU21, rotates the conveyance rollers 2a and 2b at a predetermined speed and timing, and moves the conveyance belt 2c around.

The input/output interface 83 mediates transmission and reception of data between the external device 200 and the control unit 20. The input/output interface 83 is constituted by any one of various serial interfaces, various parallel interfaces, or a combination thereof, for example.

The bus 84 is a path for transmitting and receiving signals between the control unit 20 and another structure.

The external device 200 is, for example, a personal computer, and supplies a print job, image data, and the like to the control unit 20 via the input/output interface 83.

As described above, the inkjet head 100 of the present embodiment includes: an ink ejection portion 10 having an opening portion of a nozzle 111 for ejecting ink on an ink ejection surface 112, and a piezoelectric element 123 as an operation element for performing an operation for ejecting ink from the opening portion of the nozzle 111; a drive substrate 30 provided with a drive circuit for driving the piezoelectric element 123; and an ink cartridge 60, wherein the ink cartridge 60 stores ink supplied to the ink ejecting section 10, and the ink cartridge 60 is provided such that an opposing surface 60a of the ink cartridge 60 is provided along the driving substrate 30 and heat of the driving substrate 30 is transferred to the opposing surface 60 a.

With such a configuration, the ink cartridge 60 can function as a heat sink that receives heat from the drive board 30 and discharges the heat to the outside. That is, a part of the heat transmitted from the driving board 30 to the ink cartridge 60 can be discharged to the outside space from the outer surface of the ink cartridge 60 or can be discharged to the outside through the exterior member 51 to which the ink cartridge 60 is attached. Further, since a part of the heat transferred to the ink cartridge 60 is transferred to the ink in the ink cartridge 60, the heat of the driving substrate 30 can be discharged to the outside together with the ink by guiding the ink to the outside of the inkjet head 100 through a predetermined path.

This can suppress the occurrence of the following problems: the ink in the ink ejection portion 10 is transferred by the heat of the drive substrate 30, and the viscosity of the ink is reduced, so that the ink cannot be properly ejected from the nozzles 111, or the ink ejection portion 10 is expanded by the heat of the drive substrate 30, so that the positions of the nozzles 111 are changed. As a result, the deterioration of the image quality of the recorded image due to the heat of the drive substrate 30 can be effectively suppressed.

The drive substrate 30 is provided on the side of the ink ejecting section 10 opposite to the ink ejecting surface 112, along a direction intersecting the ink ejecting surface 112. According to the configuration described above, since the drive substrate 30 can be disposed by utilizing the space on the opposite side of the ink ejection surface 112 of the ink ejection portion 10, the size of the inkjet head 100 in the direction parallel to the ink ejection surface 112 can be suppressed to be small and the drive substrate 30 can be provided in the inkjet head 100. Further, by disposing the ink cartridge 60 so that the facing surface 60a of the ink cartridge 60 is along the drive substrate 30 disposed in this way, the ink cartridge 60 can be provided in the ink jet head 100 while the size of the ink jet head 100 in the direction parallel to the ink ejection surface 112 is kept small.

Further, the ink cartridge 60 is provided with: an in-cartridge flow path F1 through which ink supplied to the ink ejecting section 10 flows in a predetermined supply direction; and a filter 61 provided along the facing surface 60a inside the cartridge flow path F1 and serving as a first filter through which the ink flowing in the cartridge flow path F1 passes. By providing the filter 61 along the facing surface 60a in the ink cartridge 60 in this manner, the filter 61 having a large area can be provided while minimizing the increase in the size of the inkjet head 100. This can suppress the pressure loss of the ink when the ink flowing through the cartridge flow path F1 passes through the filter 61 to a small level. Therefore, it is possible to reduce the back pressure for flowing the ink or increase the flow rate of the ink at the same back pressure within a range in which a required flow rate of the ink can be ensured. This enables foreign matter mixed in the ink to be efficiently captured by the filter 61. Further, since the ink can be efficiently flowed, heat of the drive substrate 30 and bubbles in the ink can be more easily discharged to the outside.

The cartridge flow path F1 includes: an upstream side ink chamber 62 adjacent to an upstream side of the filter 61 in the feeding direction; and a downstream ink chamber 63 adjacent to the downstream side of the filter 61 in the supply direction, and an upstream ink chamber 62 is provided on the facing surface 60a side of the filter 61.

In this structure, the upstream side ink chamber 62 is provided on the side close to the drive substrate 30. The ink that has flowed into the upstream ink chamber 62 is retained in the upstream ink chamber 62 until it moves to the downstream ink chamber 62 through the filter 61, and therefore, the flow rate of the ink in each portion in the upstream ink chamber 62 is likely to be as low as possible. Therefore, heat from the drive substrate 30 can be transmitted to the ink substantially uniformly and efficiently at each position in the upstream ink chamber 62. This enables efficient discharge of heat from the drive substrate 30 via the ink in the ink cartridge 60.

The ink ejection unit 10 has an outlet 102 through which a part of the ink flowing from the cartridge flow path F1 flows out, and the inkjet head 100 includes an ink discharge flow path 721 through which the ink flowing out from the outlet 102 of the ink ejection unit 10 is guided to the outside of the inkjet head 100. In this way, by adopting a configuration in which ink not ejected from the nozzle 111 among the inks supplied from the ink cartridge 60 to the ink ejection portion 10 is guided to the outside and is caused to flow back, the flow rate of ink in the cartridge flow path F1 of the ink cartridge 60 can be increased. This allows heat transferred to the driving substrate 30 of the ink and bubbles in the ink to flow more efficiently together with the ink and be discharged to the outside.

The inkjet head 100 further includes: a bypass flow path F2 connecting the in-cartridge flow path F1 and the ink discharge flow path 721 via the ink ejection section 10, by the bypass flow path F2; a filter 61 as a second filter provided inside the bypass flow path F2 for ink flowing in the bypass flow path F2 to pass through; and a check valve 73, the check valve 73 being provided between a connection position in the ink discharge flow path 721 connected to the bypass flow path F2 and an outlet (outlet 72) of the ink discharge flow path 721, not allowing ink to pass in a direction opposite to a direction toward the outlet 72.

The bypass flow path F2 can also discharge heat transferred from the drive substrate 30 to the outside from the outlet 72 together with ink, or discharge bubbles in ink to the outside from the outlet 72. Further, the ink discharge path through the bypass flow path F2 has a shorter flow path length than the ink discharge path through the ink ejection portion 10, and therefore, the pressure loss can be reduced. Therefore, the ink discharge path through the bypass flow path F2 allows heat to be radiated and air bubbles to be removed more efficiently than the ink discharge path through the ink ejection unit 10.

Further, by providing the check valve 73, the ink can be prevented from flowing backward from the outlet 72 side to the ink ejection portion 10. Therefore, the following problems can be suppressed: such a reverse flow of ink causes air bubbles, foreign substances, and the like to be mixed into the nozzle 111 and the ink flow path communicating with the nozzle 111.

The bypass flow path F2 is provided inside the ink cartridge 60, and the first filter and the second filter are provided integrally. This reduces the number of components constituting the inkjet head 100, and suppresses an increase in manufacturing cost. In addition, the ink jet head 100 can be miniaturized.

The inkjet head 100 further includes mounting screws 54 as mounting members for detachably fixing the ink cartridges 60. By adopting the structure in which the ink cartridge 60 is detachably fixed as described above, when the filter 61 is clogged or deteriorates with the passage of time, the filter 61 can be easily replaced at low cost by replacing the ink cartridge 60.

Further, a cover member 52 covering at least a part of the drive substrate 30 is provided between the ink cartridge 60 and the drive substrate 30, and a heat radiating member 53 in contact with the cover member 52 and the ink cartridge 60 is provided between the cover member 52 and the ink cartridge 60. This enables heat of the drive substrate 30 to be more efficiently transmitted to the ink cartridge 60.

Further, the amount of heat radiated from the front surface of the drive substrate 30 when the drive circuit is operated is larger than the amount of heat radiated from the rear surface of the drive substrate 30, and the ink cartridge 60 is provided on the front surface side of the drive substrate 30, and by adopting the above configuration, the heat of the drive substrate 30 can be efficiently transmitted to the ink cartridge 60 and discharged.

Further, since the inkjet recording apparatus 1 of the present embodiment includes the inkjet head 100, it is possible to effectively suppress the degradation of image quality due to the heat of the driving substrate 30 in the inkjet head 100.

(modification example)

Next, a modified example of the above embodiment will be described.

In the above embodiment, the upstream ink chamber 62 and the upstream auxiliary ink chamber 65 are provided on the-Y direction side (the facing surface 60a side) of the filter 61 in the ink cartridge 60, and the downstream ink chamber 63 and the downstream auxiliary ink chamber 66 are provided on the + Y direction side of the filter 61 in the ink cartridge 61, but in the present modification, the positional relationship of these ink chambers with respect to the filter 61 is reversed. That is, in the present modification, the downstream ink chamber 63 and the downstream auxiliary ink chamber 66 are provided on the-Y direction side (facing surface 60a side) with respect to the filter 61, and the upstream ink chamber 62 and the upstream auxiliary ink chamber 65 are provided on the + Y direction side with respect to the filter 61.

In this configuration, since the downstream ink chamber 63 is provided on the side close to the facing surface 60a, that is, on the side close to the drive substrate 30, the ink after moving from the upstream ink chamber 62 to the downstream ink chamber 63 through the filter 61 is easily heated by the drive substrate 30.

Here, as shown in fig. 12, in the downstream side ink chamber 63, the ink flows toward the opening a2 provided at the upper right in the figure, and therefore, the flow rate of the ink in the region R near the opening a2 is faster than the flow rate of the ink in the other regions.

Therefore, according to the configuration of the present modification in which the downstream ink chamber 63 is provided on the facing surface 60a side of the filter 61, the heat absorbed by the ink in the region R can be quickly discharged to the bypass passage 64, and therefore, the heat discharge efficiency in the region R is increased (in other words, the region R can be cooled intensively). Therefore, by disposing the circuit device (for example, the driving element 31) having a large heat generation amount in the range overlapping the region R as viewed from the Y direction in the driving substrate 30, it is possible to efficiently absorb heat emitted from the circuit device and discharge the heat to the outside together with the ink.

The present invention is not limited to the above embodiments, and various modifications can be made.

For example, the shape and the arrangement of the ink cartridge 60 are not limited to those described in the above embodiments, and any shape and arrangement may be adopted within a range satisfying the condition that the facing surface 60a is along the drive substrate 30 and the heat of the drive substrate 30 is transferred to the facing surface 60 a.

In the above-described embodiment, the ink cartridge 60 has been described as an example in which the opposing surface 60a and the surface on the opposite side (front surface side) of the opposing surface 60a are both flat, but the shape of the surface other than the opposing surface 60a of the ink cartridge 60 is not limited to this, and any shape can be adopted within the range of being housed in the head unit 3.

In the above embodiment, the example in which the drive substrate 30 and the ink cartridge 60 are opposed to each other with the cover member 52 and the heat dissipating member 53 interposed therebetween has been described, but the present invention is not limited to this, and for example, the drive substrate 30 and the ink cartridge 60 may be directly opposed to each other. Specifically, an opening may be provided in a portion of the cover member 52 covered by the ink cartridge 60, so that the heat of the drive substrate 30 is directly radiated to the ink cartridge 60 through the opening.

The mode in which the facing surface 60a is along the drive substrate 30 includes a mode in which the facing surface 60a is inclined at some angle (for example, about several degrees to ten or so degrees) with respect to the drive substrate 30, in addition to a mode in which the facing surface 60a is parallel to the drive substrate 30.

Instead of the ink cartridge 60 being detachably provided, the ink cartridge 60 may be fixed so as not to be detachable.

In the above-described embodiment, the example in which the drive substrate 30 is provided perpendicularly to the ink ejection surface 112 of the ink ejection portion 10 has been described, but the present invention is not limited thereto, and the drive substrate 30 may be provided in any direction intersecting the ink ejection surface 112. In addition, when the arrangement space of the drive substrate 30 and the ink cartridge 60 can be secured, the drive substrate 30 may be provided in parallel with the ink ejection surface 112.

Further, the ink cartridge 60 may be disposed on the rear surface side of the drive substrate 30 in a configuration in which the amount of heat radiated from the rear surface side of the drive substrate 30 is larger than the amount of heat radiated from the front surface side (for example, the drive element 31 is attached to the rear surface side of the drive substrate 30).

The configuration of the cartridge flow path F1 in the ink cartridge 60 of the above embodiment is an example, and the cartridge flow path F1 may be any other configuration capable of supplying the ink flowing from the inlet 71 to the ink ejecting section 10.

In the above-described embodiment, the bypass flow path F2 has been described as being provided inside the ink cartridge 60, but the present invention is not limited to this, and the bypass flow path F2 may be provided outside the ink cartridge 60. In this case, it is preferable to provide a filter (second filter) in the bypass flow path F2 separately from the filter 61 of the ink cartridge 60.

In the above-described embodiment, the example in which the ink supply channel 711 and the ink discharge channel 721 are provided in the ink cartridge 60 has been described, but the present invention is not limited to this, and at least one of the ink supply channel 711 and the ink discharge channel 721 may be provided outside the ink cartridge 60.

In the above-described embodiment, the inkjet head 100 having the inkjet head chip of the discharge mode (vent mode) in which the pressure of the ink in the pressure chamber is varied by deforming the piezoelectric element 123 to eject the ink has been described as an example, but the present invention is not limited thereto. For example, the present invention may be applied to an inkjet head having a shear mode inkjet head chip that ejects ink by repeating shear mode (shear mode) type displacement of a piezoelectric member constituting a wall surface of a pressure chamber to vary the pressure of the ink in the pressure chamber.

In the above embodiments and modifications, the recording medium M is conveyed by the conveying unit 2 including the conveyor belt 2c, but the present invention is not limited thereto, and the conveying unit 2 may convey the recording medium M while holding it on the outer peripheral surface of a rotating conveyor drum, for example.

In the above embodiments and modifications, the single-pass inkjet recording apparatus 1 was described as an example, but the present invention may be applied to an inkjet recording apparatus that records an image while scanning the inkjet head 100.

The present invention is described in the embodiments, but the scope of the present invention is not limited to the embodiments described above, and includes the scope of the invention described in the claims and the equivalent scope thereof.

Industrial applicability

The present invention can be used for an ink jet head and an ink jet recording apparatus.

Description of the reference numerals

1 ink jet recording apparatus

2 conveying part

3 ink jet head unit

9 ink circulation mechanism

10 ink ejection part

101 inflow port

102 outflow opening

11 nozzle base plate

111 nozzle

112 ink ejection face

12 actuator substrate

123 piezoelectric element

13 common ink chamber

131 first common ink chamber

132 second common ink chamber

20 control part

30 drive base plate

31 drive element

32 first connector

33 second connector

40 wiring component

51 exterior component

52 cover component

53 Heat dissipation Member

54 mounting screw

60 ink box

60a facing surface

601 base part

602 cover

603 fixed part

61 Filter

62 upstream side ink chamber

63 downstream side ink chamber

64-lead bypass flow path

65 upstream side auxiliary ink chamber

66 downstream side auxiliary ink chamber

67 communication flow path

68 partition member

71 inlet

711 ink supply flow path

72 outlet

721 ink discharge flow path

73 check valve

100 ink jet head

Flow path in F1 Cartridge

F2 bypass flow path

HC ink-jet head chip

M recording medium