JP2020059241A - Liquid discharge head and liquid discharge device - Google Patents

Abstract

To provide a liquid discharge head capable of uniformizing the temperature distribution of an element substrate.SOLUTION: An element substrate 2 of a liquid discharge head has plural feeding ports 25 from which a liquid is fed and discharges an ink fed to the feeding ports 25. A support member 5 has a first face 5a supporting the element substrate 2, and a penetration flow path 6 penetrating from the first face 5a to a second face 5b on a side opposite to the first face 5a. Besides, the support member 5 has a beam 7 extending along the feeding port 25 at a position facing an area between two feeding ports 25 adjacent to each other in the element substrate 2. The face-to-face distance La which is the distance between a third face 7a facing the element substrate 2 of the beam 7 and the element substrate 2 differs by the position in a drawing direction along which the beam 7 extends.SELECTED DRAWING: Figure 6

Description

  The present invention relates to a liquid ejection head and a liquid ejection device that eject liquid.

A liquid ejection device such as an inkjet recording device is equipped with a liquid ejection head that ejects a liquid. The liquid ejection head usually has an element substrate having an ejection port for ejecting a liquid, and a support member that supports the element substrate. The element substrate has an energy generating element that generates energy for ejecting the liquid from the ejection port. The support member is formed with a channel for supplying a liquid to the element substrate.
When a heater (heat generation resistance element) that generates thermal energy is used as the energy generation element, an uneven temperature distribution occurs on the element substrate even if all the heaters on the element substrate generate heat energy uniformly. It may happen. When the nonuniform temperature distribution occurs in the element substrate, the nonuniform temperature distribution also occurs in the liquid in the element substrate. The discharge amount of the liquid changes depending on the temperature of the liquid even when the heater generates the same thermal energy. Therefore, when a non-uniform temperature distribution occurs in the element substrate, the discharge amount is discharged according to the temperature distribution. There is a risk that it will change at each exit. In this case, density unevenness may occur in the recorded image.
Patent Document 1 discloses a liquid ejection head capable of making the temperature distribution of an element substrate uniform. In this liquid ejection head, a plurality of beams that come into contact with the element substrate are provided in the flow path formed in the support member. Thereby, the heat of the element substrate can be radiated through the beam, and thus the temperature distribution of the element substrate can be made uniform by appropriately disposing the beam.

JP, 2007-276385, A

  In recent years, there has been a demand for higher speeds in liquid ejection heads, and along with this, there has been a demand for improvement in ejection frequency, higher density of ejection ports, lengthening of ejection port arrays and the like. Since these measures promote the temperature rise of the element substrate and the non-uniformity of the temperature distribution of the element substrate, further techniques for equalizing the temperature distribution of the element substrate are required.

  An object of the present invention is to provide a liquid ejection head and a liquid ejection device that can make the temperature distribution of an element substrate uniform.

A liquid discharge head according to the present invention has a plurality of supply ports for supplying a liquid, has an element substrate that discharges the liquid supplied to the supply port, and a first surface that supports the element substrate, A liquid discharge head, comprising: a support member having a flow passage that penetrates from the first surface to a second surface opposite to the first surface, the flow passage communicating with the supply port. The support member has a first partition member extending along the supply port at a position facing a region between the two supply ports adjacent to each other on the element substrate, and the first partition member. The distance between the element substrate and the element substrate varies depending on the position in the extending direction in which the first partition member extends.
A liquid ejection apparatus according to the present invention includes the liquid ejection head.

  According to the present invention, the distance between the first partition member and the element substrate differs depending on the position in the extending direction in which the first partition member extends. Since the heat dissipation efficiency of the element substrate changes according to the distance between the first partition member and the element substrate, it is possible to change the heat dissipation efficiency of the element substrate according to the position of the first partition member in the extending direction. become. Therefore, the temperature distribution of the element substrate can be made more uniform.

FIG. 3 is a perspective view showing the liquid ejection head according to the first embodiment of the present invention. It is a perspective view which shows the support member which concerns on the 1st Embodiment of this invention. It is a perspective view which shows the element substrate which concerns on the 1st Embodiment of this invention. It is sectional drawing which followed the AA line of FIG. FIG. 5 is a partially enlarged view of FIG. 4. It is sectional drawing which followed the BB line of FIG. It is a figure which shows the liquid discharge head of a reference example. It is a figure which shows the temperature distribution of the element substrate which concerns on the 1st Embodiment of this invention, and the element substrate which concerns on a reference example. FIG. 6 is a cross-sectional view showing a liquid ejection head according to a second embodiment of the present invention. It is a figure which shows the temperature distribution of the element substrate which concerns on the 2nd Embodiment of this invention. It is a figure for demonstrating the 3rd Embodiment of this invention. It is a perspective view showing a support member concerning a 4th embodiment of the present invention. It is sectional drawing which shows the liquid discharge head which concerns on the 4th Embodiment of this invention. It is a figure which shows the temperature distribution of the element substrate which concerns on the 4th Embodiment of this invention, and the element substrate which concerns on a reference example. It is sectional drawing which shows the liquid discharge head which concerns on the 5th Embodiment of this invention. It is a figure which shows the temperature distribution of the element substrate which concerns on the 5th Embodiment of this invention, and the element substrate which concerns on a reference example. It is sectional drawing which shows the liquid discharge head which concerns on the 6th Embodiment of this invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings, components having the same function are designated by the same reference numerals and the description thereof may be omitted.
(First embodiment)
FIG. 1 is a perspective view showing a liquid ejection head according to a first embodiment of the present invention. The liquid ejection head 1 shown in FIG. 1 is mounted on a liquid ejection device (not shown) that ejects a liquid such as ink such as an inkjet recording device. In this embodiment, the liquid is ink.
The liquid ejection head 1 supports the element substrate 2 for ejecting ink, a housing 4 having an inlet 3 for introducing ink from a main tank (not shown) provided in the liquid ejection device, and the element substrate 2. And a supporting member 5. In the figure, two directions in the plane of the support member 5 that support the element substrate 2 orthogonal to each other are the X direction and the Y direction, and the direction orthogonal to the X direction and the Y direction is the Z direction.
The element substrate 2 includes a heater (not shown) that generates thermal energy as an energy generation element that generates energy for ejecting ink, and ejects ink by driving the heater. In the illustrated example, six element substrates 2 are arranged, but the number of element substrates 2 is not particularly limited.
The inlet 3 is connected to a main tank provided in the liquid ejection apparatus main body via a tube (not shown). Ink is introduced into the introduction port 3 from the main tank via a tube. In the example of the figure, there are a plurality of inlets 3, and inks of different colors are supplied to each of the plurality of inlets 3.
The housing 4 has a function of supplying the ink introduced into the introduction port 3 to the element substrate 2. Specifically, the housing 4 includes a sub-tank for storing the ink introduced into the introduction port 3, a flow path for supplying the ink to the element substrate 2, and a liquid chamber for trapping bubbles and dust in the ink (both are shown in FIG. (Not shown) and the like. The housing 4 is formed, for example, by injection molding a resin material.
The support member 5 is joined to the housing 4, and the element substrate 2 is joined to the housing 4 via the support member 5.
Note that, in FIG. 1, the liquid ejection head 1 is shown in a state in which the element substrate 2 is disposed above the housing 4, but when recording is performed by ejecting liquid, the FIG. In this state, that is, in a state where the element substrate 2 is below the housing 4, the device is used.

FIG. 2 is a diagram showing the support member 5. Specifically, FIG. 2A is a front view of the support member 5, and FIG. 2B is a perspective view of the support member 5.
The support member 5 requires high dimensional accuracy and high rigidity in order to arrange the element substrates 2 with high accuracy. Further, the support member 5 also functions as a heat dissipation member for radiating the heat generated in the element substrate 2. Therefore, the support member 5 needs to have heat dissipation. From these viewpoints, it is desirable that the support member 5 be formed of a material having a high thermal conductivity. For example, the support member 5 is made of aluminum oxide (alumina) or a material having a higher thermal conductivity than aluminum oxide. The support member 5 is preferably molded by CIM (ceramic injection mold). In this case, the cost can be kept low as compared with the case where the parts are formed by machining such as cutting.
The support member 5 also functions as a flow path member for supplying ink from the housing 4 to the element substrate 2. Therefore, as shown in FIG. 2, the support member 5 has a plurality of through flow paths 6 as flow paths for supplying ink from the housing 4 to the element substrate 2. The through flow path 6 penetrates the support member 5 in the Z direction and connects the element substrate 2 and the housing 4 to each other. The through channel 6 is formed along the Y direction.
The support member 5 has a beam 7 that is a first partition member that divides each of the through channels 6 into two. The beam 7 extends along the Y direction, which is the longitudinal direction of the through channel 6. As a result, the beam 7 partitions the through channel 6 in the X direction, which is the lateral direction of the through channel 6.

FIG. 3 is a perspective view showing the element substrate 2. As shown in FIG. 3, the element substrate 2 has a substrate 21 and a discharge port forming member 22 provided on the substrate 21. Terminals 23 for inputting an electric signal to the element substrate 2 are provided near both ends in the Y direction, which is the longitudinal direction of the substrate 21.
The ejection port forming member 22 has a plurality of ejection ports 24 for ejecting ink. The plurality of discharge ports 24 form a discharge port array 24a along the Y direction. In the illustrated example, the two ejection port arrays 24a are arranged in parallel in the X direction, but the number is not limited to two, and may be four, for example. Further, the heater of the substrate 21 is provided at a position facing each of the ejection ports 24. Therefore, the heater forms a heater array along the Y direction.
At the time of ejecting ink, the heater is driven according to an electric signal input to the terminal 23, and the thermal energy generated by the heater causes the ink to be ejected from the ejection port 24 as a droplet. The droplets form an image on a recording medium (not shown) such as paper. At this time, the element substrate 2 generates heat due to the heat energy generated by the heater, etc., and the temperature distribution of the element substrate 2 changes accordingly.

FIG. 4 is a sectional view taken along the line AA of FIG. Note that FIG. 4 shows the liquid ejection head 1 in a state at the time of recording, that is, a state in which FIG. 1 is turned upside down.
As shown in FIG. 4, the substrate 21 of the element substrate 2 is bonded to the first surface 5a of the support member 5 via an adhesive layer (not shown) formed of an adhesive. The support member 5 is joined to the housing 4 on the second surface 5b opposite to the first surface 5a via the adhesive layer 8 formed of an adhesive. The through channel 6 penetrates from the first surface 5a to the second surface 5b of the support member 5 along the Z direction. In this embodiment, inks of different colors are supplied to each of the plurality of through channels 6. This makes it possible to eject ink of a plurality of colors.
The element substrate 2 has a supply port 25 that communicates with the through channel 6 and that is supplied with ink from the through channel 6. The element substrate 2 ejects the ink supplied to the supply port 25 from the ejection port 24.
The beam 7 of the support member 5 is provided at a position facing a region between two adjacent supply ports 25 on the element substrate 2. In the present embodiment, the third surface 7a of the beam 7 that faces the element substrate 2 and the first surface 5a of the support member 5 are arranged in the same plane. Further, the length of the beam 7 in the Z direction, which is the penetrating direction of the through channel 6, is shorter than the length of the through channel 6 in the Z direction. Therefore, in the present embodiment, the beam 7 divides the through flow path 6 into two on the element substrate 2 side.

FIG. 5 is an enlarged view of the vicinity of the through flow path 6 of the liquid ejection head 1 shown in FIG. The through-flow passage 6 has an opening 61 on the first surface 5 a of the support member 5 and an opening 62 on the second surface 5 b of the support member 5. It is desirable that the width (length in the X direction) of the through flow path 6 be equal to or larger than the width L1 of the opening 61 regardless of the location. Further, in the example of the drawing, the width L3 near the central portion of the through channel 6 in the Z direction is wider than the width L2 of the opening 62. The width of each of the through flow paths 6 separated by the beam 7 is substantially the same as the width L1 of the opening 61.
When air bubbles generated in the ink stay near the opening 61 during recording or suction recovery for normalizing the ejection port 24, the ink supply to the element substrate 2 is affected. It is preferable to be removed promptly.
It is assumed that the bubble 40 is generated near the opening 61 as shown in FIG. 5 (state 40a). In FIG. 5, as the bubble 40, the maximum bubble in consideration of the surface tension of the bubble, that is, the bubble having a diameter similar to the width L1 of the opening 61 is shown.
In this case, in the vicinity of the opening 61, the surface tensions of the upper surface (the surface on the housing 4 side) and the lower surface (the surface on the element substrate 2 side) of the bubble 40 are substantially equal. In this case, the bubbles 40 rise due to the buoyancy acting on the ink and move to the housing 4 side. After that, when the upper surface of the bubble 40 passes through the position where the beam 7 is provided and moves to the position where the width of the through flow path 6 becomes wide (state 40b), the surface tension of the upper surface of the bubble 40 becomes smaller than the surface tension of the lower surface. Become. Due to the difference in surface tension, a force is applied to the bubble 40 in a rising direction. Therefore, the bubble 40 does not stay and further rises (state 40c), and then moves to the housing 4. Therefore, the bubbles 40 generated in the ink can be promptly removed. Since the housing 4 is provided with a liquid chamber for trapping bubbles in the ink, the influence of the bubbles 40 moved to the housing 4 can be ignored.
In the above example, the width of each of the through flow paths 6 separated by the beam 7 is substantially the same as the width L1 of the opening 61. However, in consideration of the releasability of the ink to the wall surface of the through flow path 6, It may become narrower as it goes away from the opening 61. In this case, the surface tension of the upper surface of the bubble 40 becomes larger than the surface tension of the lower surface, and thereby a force is applied to the bubble 40 in the descending direction. However, even in this case, the bubble 40 can be removed by adjusting the amount of change in which the through passage 6 becomes narrow so that the force applied in the descending direction does not become larger than the buoyancy acting on the bubble 40. .
Further, in the present embodiment, the width L1 of each of the two openings 61 sandwiching the beam 7, the width L4 of the beam 7, and the width L2 of the opening 62 satisfy the relationship of 2 × L1 + L4> L2. In this case, it is possible to secure a sufficient area in the bonding area 51 where the adhesive layer 8 for bonding the housing 4 and the support member 5 is provided. Further, not only the adhesion area 51, but also an area necessary for sealing the element substrate 2 with a rubber member or the like can be secured.

FIG. 6 is a sectional view taken along the line BB of FIG. It should be noted that FIG. 6 shows the liquid ejection head 1 in the state during recording as in FIGS. 4 and 5.
As shown in FIG. 6, the length of the opening 61 of the through-flow passage 6 of the support member 5 in the Y direction is longer than the length of the opening 62 in the Y direction. Further, a plurality of beams 9, which are second partition members, extending in a direction substantially orthogonal to the beam 7 are arranged in the through flow path 6. The surface 9a of the beam 9 on the housing 4 side and the second surface 5b of the support member 5 are arranged in the same plane. Further, the length of the beam 9 in the Z direction is shorter than the length of the through passage 6 in the Z direction. In the example of FIG. 6, two beams 9 are provided for one through passage 6. Specifically, the beam 9 is provided near both ends of the opening 62 in the Y direction, that is, between the center and both ends of the beam 7 in the Y direction.
Further, the beam 7 is provided along the Y direction, which is the longitudinal direction of the supply port 25 of the element substrate 2. The third surface 7 a of the beam 7 on the element substrate 2 side is provided with a recess 30 that is a first recess. In the present embodiment, the recesses 30 are provided at both ends in the Y direction, which is the extending direction of the beam 7. More specifically, the recess 30 is provided at a position closer to both ends of the beam 7 than the position where the beam 9 is provided in the Y direction. As a result, the facing distance, which is the distance between the beam 7 and the element substrate 2, becomes longer only at the location where the recess 30 is provided than at other locations. Therefore, the facing distance differs depending on the position in the Y direction. In the present embodiment, the beam 7 is flat except for the portion where the concave portion 30 is provided on the third surface 7a, which is the surface on the element substrate 2 side. The bottom surface of the recess 30 is also flat.
In addition, the support member 5 has a bonding region 52 that is bonded to the element substrate 2 on both sides of the beam 7 in the Y direction (on the extension line of the beam 7), and the bonding region 52 has a recess 31 that is a second recess. It is provided.
The beams 7 and 9 form a part of the support member 5 and are made of the same material as the main body of the support member 5. For this reason, the beams 7 and 9 also function as a heat dissipation member similarly to the main body of the support member 5.

FIG. 7 is a cross-sectional view of the liquid ejection head of the reference example.
In the liquid ejection head 1a of the first reference example shown in FIG. 7A, three beams 9 are provided near the center of the opening 62 in the Y direction, and no recesses 30 and 31 are provided. However, this is different from the liquid ejection head 1 of the present embodiment.
The liquid ejection head 1b of the second reference example shown in FIG. 7B is different from the liquid ejection head 1 of the present embodiment in that the recesses 30 and 31 are not provided.
In the liquid ejection head 1c of the third reference example shown in FIG. 7C, the beam 9 is provided near the both ends of the opening 62 in the Y direction, and one more beam is provided substantially at the center of the opening 62 in the Y direction. The liquid ejecting head 1 of the present embodiment is different in that the concave portions 30 and 31 are not provided.

FIG. 8 is a diagram showing a temperature distribution in the Y direction of the element substrate 2 in the liquid ejection head 1 of the present embodiment and the liquid ejection heads 1a to 1c of the reference example. In FIG. 8, the horizontal axis represents the position of the element substrate 2 in the Y direction, and the vertical axis represents the temperature. The ejection port array 24a includes 1280 ejection ports 24 from the 0th (0seg) to the 1279th (1279seg), and the position of the element substrate 2 in the Y direction is indicated by the position of the ejection port 24. The temperature indicates an actually measured value when ink is continuously ejected from all the ejection ports (1280 ejection ports) 24 in the ejection port array 24a for one column for a predetermined time.
If the temperature distribution of the element substrate 2 in the Y direction has a large variation, the energy used when ejecting ink changes for each ejection port 24, and as a result, the size of the ejected droplets changes. It changes every time. In this case, the liquid droplets cause shading in the image formed on the recording medium, which deteriorates the print quality of the image. Therefore, it is desirable that the Y-direction temperature distribution of the element substrate 2 be close to uniform.
As shown in FIG. 8, in the temperature distribution 81 of the liquid ejection head 1a, the temperature in the vicinity of the central portion of the element substrate 2 is considerably lower than both sides thereof. This is because the beams 9 functioning as a heat dissipation member are concentrated near the central portion of the element substrate 2, so that the heat dissipation efficiency near the central portion of the element substrate 2 is high.
In the temperature distribution 82 of the liquid ejection head 1b, the temperature in the vicinity of the central portion of the element substrate 2 is higher than that of the element substrate 2 of the liquid ejection head 1a, and is uniform throughout. This is because there is no beam 9 near the center of the element substrate 2 and the beams 9 are provided at both ends of the element substrate 2.
Further, in the temperature distribution 83 of the liquid ejection head 1c, since the beam 9 is provided in the central portion of the element substrate 2, the temperature of the central portion of the element substrate 2 is low like the temperature distribution 81 of the liquid ejection head 1a. Has become.
Depending on the shape of the through channel 6, the flow velocity of the ink in the through channel 6 may be highest near the center of the opening 62 in the Y direction. In this case, since the heat dissipation efficiency of the element substrate 2 is higher at a place where the ink flow velocity is faster, the heat dissipation efficiency of the central portion of the element substrate 2 is higher than that at other places. In particular, when the recording speed is increased, the temperature distribution of the element substrate 2 is likely to be non-uniform because the difference in the flow velocity of the ink in the through channel 6 tends to increase. In the liquid ejection heads 1b and 1c, since the beams 9 are arranged at both ends of the opening 62 where the ink flow velocity is slower than that of the liquid ejection head 1a, the variation in the temperature distribution due to the difference in the ink flow velocity is suppressed. You can
From the above viewpoints, the liquid ejection head 1b can make the temperature distribution most uniform among the liquid ejection heads 1a to 1c. However, as shown in FIG. 8, not only in the liquid ejection head 1b but also in all the liquid ejection heads 1a to 1c of the reference example, the temperature of both end portions of the element substrate 2 in the Y direction is lower than that of other portions. . This is because the element substrate 2 has a large area in contact with the support member 5, which is a heat dissipation member.

On the other hand, in the liquid ejection head 1 of the present embodiment, in addition to the configuration of the liquid ejection head 1b, the recesses 30 and 31 are provided at both ends and both sides of the beam 7 in the Y direction. It is possible to reduce the heat dissipation efficiency at both ends of the. Therefore, as shown by the temperature distribution 80 of the liquid ejection head 1, the temperatures of both ends of the element substrate 2 are higher than those of the liquid ejection heads 1a to 1c. Therefore, the temperature distribution of the element substrate 2 of the liquid ejection head 1 is made more uniform than the temperature distribution of the element substrate 2 of the liquid ejection heads 1a to 1c.
Note that the heat radiation efficiency of the element substrate 2 changes according to the size of the element substrate 2 and the ejection port 24, and the like, but by changing the positions and sizes of the concave portions 30 and 31 according to the change of the heat radiation efficiency, the temperature The distribution can be made uniform. Therefore, even if the shape of the supporting member 5 is not largely changed, it is possible to deal with various element substrates 2.

As described above, according to the present embodiment, the facing distance, which is the distance between the element substrate 2 and the third surface 7a of the beam 7 that faces the element substrate 2, is the extending direction Y of the beam 7. It depends on the position in the direction. Since the heat dissipation efficiency of the element substrate 2 changes according to the facing distance, it becomes possible to change the heat dissipation efficiency of the element substrate 2 according to the extending direction of the beam 7. Therefore, it becomes possible to make the temperature distribution of the element substrate 2 uniform.
Further, in this embodiment, the recesses 30 are formed at both ends of the third surface 7a of the beam 7 in the Y direction. Therefore, it is possible to reduce the heat dissipation of both end portions of the element substrate 2 in the Y direction, so that the temperature distribution of the element substrate can be appropriately made uniform. Further, since the facing distance can be adjusted by adjusting the position and size of the concave portion 30, it becomes possible to easily adjust the temperature distribution of the element substrate 2.
Further, the support member 5 has a bonding region 52 bonded to the element substrate 2 on both sides of the beam 7 in the Y direction, and the bonding region 52 is provided with a recess 31 that is a second recess. Therefore, it is possible to reduce the heat dissipation of both end portions of the element substrate 2 in the Y direction, so that the temperature distribution of the element substrate can be appropriately made uniform.
Further, the length of the beam 7 in the X direction, which is the penetrating direction through which the through channel 6 penetrates, is shorter than the length of the through channel 6 in Z, and the third surface 7 a of the beam 7 and the first of the support member 5 are Surface 5a is provided on the same plane. Therefore, an adhesive that bonds the housing 4 and the supporting member 5 together with widening the width of the opening 62 of the through-flow passage 6 provided on the second surface 5b of the supporting member 5 on the housing 4 side. A sufficient area can be ensured in the bonding area 51 where the layer 8 is provided.
Further, in the present embodiment, the beam 9 extending in a direction substantially orthogonal to the beam 7 is provided between the central portion and both ends of the beam 7 in the Y direction in which the beam 7 extends. This makes it possible to increase the heat dissipation efficiency between the central portion and both end portions of the beam 7 in the Y direction. Therefore, it becomes possible to make the temperature distribution of the element substrate 2 uniform.

(Second embodiment)
FIG. 9 is a cross-sectional view of the liquid ejection head 1 according to the second embodiment of the present invention, and shows a cross section taken along the line BB of FIG.
The liquid discharge head 1 shown in FIG. 9 is different from the liquid discharge head 1 of the first embodiment shown in FIG. 6 in that a beam 19 is provided and that the beam 7 is a third face opposed to the element substrate 2. The difference is that the concave portion 32 is provided on the surface 7a of the. The beam 19 is a second partition member that extends in a direction substantially orthogonal to the beam 7 similarly to the beam 9, and is provided at the center of the opening 62 in the Y direction. The recess 32 is a third recess provided in the center of the beam 7 in the Y direction. The positions of the beam 19 and the recess 32 in the Y direction are preferably substantially the same.
FIG. 10 is a diagram showing a temperature distribution in the Y direction of the element substrate 2 in the liquid ejection head 1 of this embodiment. The vertical axis and the horizontal axis in FIG. 10 and the configuration and operation of the ejection port array 24a are the same as those in FIG. In addition, FIG. 10 also shows, for reference, temperature distributions 81 to 83 of the element substrate 2 in the liquid ejection heads 1a to 1c of the reference example.
In the liquid ejection head 1 of the present embodiment, the beam 9 is provided at the central portion of the beam 7 in the Y direction, but as shown in FIG. 10, in the temperature distribution 85 of the liquid ejection head 1 of the present embodiment, the first As in the above embodiment, the temperature of the central portion of the element substrate 2 is suppressed from being lowered. This is because the heat radiation effect of the beam 19 is canceled by the heat insulation effect of the recess 32.
Therefore, also in this embodiment, the temperature distribution of the element substrate 2 can be made uniform. Further, since the central portion of the beam 7 can be supported by the beam 19, the deformation of the beam 7 can be suppressed.

(Third Embodiment)
In this embodiment, the temperature distribution of the element substrate 2 will be described in more detail.
FIG. 11 is a diagram showing the relationship between the temperature distribution of the element substrate 2 and the wiring pattern. 11A shows the relationship between the cross section of the liquid ejection head 1 along the line BB in FIG. 1 and the heat radiation property, and FIG. 11B shows the schematic wiring pattern and wiring of the element substrate 2. The density relationship is shown. The configuration of the liquid ejection head 1 of this embodiment is the same as the configuration of the liquid ejection head 1 of the second embodiment shown in FIG.
Since the element substrate 2 and the support member 5 are bonded to each other outside the through-flow passage 6 in the Y direction, the heat dissipation efficiency of the element substrate 2 is high outside the through-flow passage 6 in the Y direction. The lower the distance to the center, the lower it becomes. Therefore, by providing the recesses 30 and 31, the heat radiation efficiency on the outside of the through channel 6 in the Y direction is reduced.
Further, the element substrate 2 generates heat when the heater is driven, and the heater is entirely arranged with respect to the element substrate 2. Therefore, at first glance, it is considered that the amount of heat generated by the element substrate 2 is generally uniform regardless of the location, or is higher in the central portion than in both end portions.
However, as shown in FIG. 11B, the element substrate 2 has the wiring 26 for transmitting the electric signal input to the terminal 23 to the heater, and the wiring 26 also generates heat. The inventors of the present application have found that the density of the wirings 26 affects the heat generation amount and the temperature distribution of the element substrate 2. Specifically, the temperature (heat generation amount) of the portion of the wiring 26 having a high density tends to be high, and the temperature (heat generation amount) of the portion of the wiring 26 having a low density tends to be low.
The density of the wirings 26 is generally higher toward both ends of the element substrate 2 and lowers toward the center thereof. Therefore, the heat generation amount becomes high at both ends of the element substrate 2 and becomes low at the central portion of the element substrate 2.
From this point of view, when the beam 19 is provided, it is desirable to provide the recess 32 at the same time. Further, it is desirable that the positions and sizes of the beams 19 and the recesses 32 are adjusted according to the density of the wirings 26.

(Fourth Embodiment)
FIG. 12 is a perspective view showing the support member 5 of this embodiment. Specifically, FIG. 12A shows the support member 5 before the element substrate 2 is joined, and FIG. 12B shows the support to which the adhesive is applied to join the element substrate 2. The member 5 is shown, and FIG. 12C shows the support member 5 to which the element substrate 2 is joined.
When joining the element substrate 2 to the support member 5, first, as shown in FIG. 12B, the dispenser 101 is used to apply the adhesive 102 to the peripheral portion of the opening 61 of the support member 5. Thereafter, as shown in FIG. 12C, the element substrate 2 is placed on the area where the adhesive 102 is applied, so that the element substrate 2 is bonded to the support member 5. The housing 4 is bonded to the surface of the supporting member 5 that faces the surface of the element substrate 2 bonded thereto.

FIG. 13 is a cross-sectional view of the liquid ejection head 1 of this embodiment. Specifically, FIG. 13A is a sectional view taken along the line AA of FIG. 1, and FIG. 13B is a sectional view taken along the line BB of FIG. Note that FIG. 13 shows the liquid ejection head 1 in the same state as in FIG.
As shown in FIG. 13, the liquid discharge head 1 includes a wall member 10 instead of the beam 7 as the first partition member, as compared with the liquid discharge head 1 of the first embodiment shown in FIG. This is different from the point that the beam 9 is not provided. Further, FIG. 13 shows an adhesive layer 11 for joining the element substrate 2 and the support member 5, which is not shown in FIG. The adhesive layer 11 is formed by curing the adhesive 102 shown in FIG.
The length of the wall member 10 in the Z direction is substantially equal to the length of the through passage 6 in the Z direction. As a result, the wall member 10 partitions the entire through channel 6.
Further, as shown in FIG. 13B, on the surface 10 a of the wall member 10 facing the element substrate 2, the facing distance La, which is the distance between the wall member 10 and the element substrate 2, depends on the position in the Y direction. Differently, the inclination is provided. Specifically, the surface 10 a of the wall member 10 is provided with an inclination such that the facing distance La becomes shorter as it approaches the central portion of the supply port 25.
Since the surface 10a is inclined, a gap is created between the wall member 10 and the element substrate 2. In order to prevent the ink from leaking from the gap, it is necessary to adjust the facing distance La to a distance at which the gap can be sealed with the adhesive layer 11. This distance changes depending on the physical properties (viscosity, thixotropy, etc.) of the adhesive 102 forming the adhesive layer 11, the coating method, and the like. Therefore, the facing distance La, that is, the inclination of the surface 10 a is the physical property of the adhesive 102. It is desirable to change appropriately according to the coating method. In this embodiment, the facing distance La is 0.1 mm or less.
Further, on the first surface 5a of the support member 5, a temporary fixing region 53 in which the distance between the support member 5 and the element substrate 2 is equal to or smaller than the minimum value of the facing distance La is formed on both sides of the wall member 10 in the Y direction. Has been done. When the element substrate 2 and the supporting member 5 are joined, the adhesive 102 applied to the temporary fixing region 53 is cured to temporarily fix the element substrate 2 and the supporting member 5, and then the adhesive agent is applied. By hardening the entire 102, the element substrate 2 and the supporting member 5 are joined. This temporary fixing makes it possible to improve the assembly accuracy of the element substrate 2.

FIG. 14 is a diagram showing the temperature distribution in the Y direction of the element substrate 2 in the liquid ejection head 1 of this embodiment. The vertical axis and the horizontal axis in FIG. 14 are the same as those in FIG. 8 regarding the configuration and operation of the ejection port array 24a.
In FIG. 14, a temperature distribution 90, which is the Y-direction temperature distribution of the element substrate 2 in the liquid ejection head 1 of the present embodiment, and a Y-direction temperature distribution of the element substrate 2 in the liquid ejection head of the fourth reference example. A temperature distribution 91 is shown. The liquid ejection head of the fourth reference example is different from the liquid ejection head 1 of the present embodiment in that the distance La between the element substrate 2 and the support member 5 is constant.
As shown in FIG. 14, in the temperature distribution 91 of the liquid ejection head of the fourth reference example, the temperature is low at both ends of the element substrate 2 and is high at the central portion of the element substrate 2. This is because both ends of the element substrate 2 have a large area in contact with the support member 5 which is a heat dissipation member.
On the other hand, in the temperature distribution 90 of the liquid ejection head 1 of the present embodiment, the temperatures at both ends of the element substrate 2 are higher than those in the fourth reference example, and as a result, the temperature distribution 90 is uniform compared to the temperature distribution 91. Has been converted. This is because the facing distance La between the wall member 10 and the support member 5 becomes longer as the distance to the both ends of the element substrate 2 becomes closer, and thus the heat dissipation property at both ends of the element substrate 2 becomes low. .
Therefore, also in this embodiment, the temperature distribution of the element substrate 2 can be made uniform.

(Fifth Embodiment)
FIG. 15 is a cross-sectional view taken along the line BB of FIG. 1 in this embodiment. Note that FIG. 15 shows the liquid ejection head 1 in the same state as in FIG.
The liquid discharge head 1 shown in FIG. 15 differs from the liquid discharge head 1 of the fourth embodiment shown in FIG. 13 in the shape of the surface 10a of the wall member 10 facing the element substrate 2. On the surface 10a of the present embodiment, the facing distance La between the element substrate 2 and the support member 5 is the shortest at a specific portion P between the central portion and both ends of the element substrate 2 in the Y direction, It has an inclination that becomes longer from the specific portion P toward the central portion and both end portions of the element substrate 2.
In addition, in the liquid ejection head 1 of the present embodiment, the flow velocity of the ink in the through flow path 6 is the highest near the center of the opening 62 in the Y direction, so that the heat dissipation efficiency of the central portion of the element substrate 2 is different. Higher than. The temperature tends to be low in the central portion and both ends of the element substrate 2, and tends to be high in the region between the central portion and both ends.

FIG. 16 is a diagram showing a temperature distribution in the Y direction of the element substrate 2 in the liquid ejection head 1 of this embodiment. The vertical axis and the horizontal axis in FIG. 16 are the same as those in FIG. 8 regarding the configuration and operation of the ejection port array 24a.
In FIG. 16, a temperature distribution 92 that is the temperature distribution in the Y direction of the element substrate 2 in the liquid ejection head 1 of the present embodiment and a temperature distribution in the Y direction of the element substrate 2 in the liquid ejection head of the fifth reference example. A temperature distribution 93 is shown. The liquid ejection head of the fifth reference example is different from the liquid ejection head 1 of the present embodiment in that the distance La between the element substrate 2 and the support member 5 is constant.
As shown in FIG. 16, in the temperature distribution 93 of the liquid ejection head of the fifth reference example, since the flow velocity of the ink in the through flow path 6 is the fastest near the center of the opening 62 in the Y direction, both end portions of the element substrate 2 are shown. And the temperature is low in the central part, and the temperature is high between both ends and the central part. On the other hand, in the liquid discharge head 1 of the present embodiment, since the surface 10a of the wall member 10 is provided with the inclination as described above, the temperatures of both ends and the center of the element substrate 2 are the fifth reference example. Is higher than.
Therefore, also in this embodiment, the temperature distribution of the element substrate 2 can be made uniform.

(Sixth Embodiment)
FIG. 17 is a cross-sectional view of the liquid ejection head 1 of this embodiment. Specifically, FIG. 17A is a cross-sectional view taken along the line AA of FIG. 1, and FIG. 17B is a cross-sectional view taken along the line BB of FIG. Note that FIG. 17 shows the liquid ejection head 1 in the same state as in FIG.
The liquid discharge head 1 of the present embodiment shown in FIG. 17 has a beam 12 instead of the wall member 10 as the first partition member as compared with the liquid discharge head 1 of the fourth embodiment shown in FIG. Different.
The length of the beam 12 in the Z direction, which is the penetrating direction of the through channel 6, is shorter than the length of the through channel 6 in the Z direction. Further, the beam 12 is provided so as to divide the through channel 6 on the element substrate 2 side into two.
The surface 12a of the beam 12 facing the element substrate 2 is provided with an inclination such that the facing distance La, which is the distance between the beam 12 and the element substrate 2, differs depending on the position in the Y direction. Specifically, the surface 12 a of the beam 12 is provided with an inclination such that the facing distance La becomes shorter as it approaches the center of the supply port 25.
In the present embodiment as well, the facing distance La, which is the distance between the surface 12a of the beam 12 that faces the element substrate 2 and the element substrate 2, differs depending on the position in the Y direction, which is the extending direction of the beam 12. It becomes possible to make the temperature distribution of the element substrate 2 uniform.
Further, in the present embodiment, since the ink of the same color is supplied to each of the through-flow passages 6 partitioned by the beam 12, the adhesive layer 11 does not seal the space between the beam 7 and the element substrate 2. It may be a void. In the figure, an example of a gap between the beam 7 and the element substrate 2 is shown. In this case, since the facing distance La does not have to be limited to the range in which the beam 7 and the element substrate 2 can be sealed with the adhesive layer 11, the facing distance La can be set relatively freely. .

  In each of the embodiments described above, the illustrated configuration is merely an example, and the present invention is not limited to the configuration.

1 Liquid Discharge Head 2 Element Substrate 5 Support Member 5a First Surface 5b Second Surface 6 Through Flow Path 7, 12 Beam (First Partition Member)
9, 19 Beam (second partition member)
10 Wall member (first partition member)
25 Supply Port 30 Recess (First Recess)
31 concave portion (second concave portion)
32 recess (third recess)

Claims (16)

An element substrate having a plurality of supply ports for supplying a liquid and ejecting the liquid supplied to the supply port, and a first surface supporting the element substrate, the first surface to the first surface A liquid discharge head in which a flow path that penetrates to a second surface opposite to the first surface is formed, and the flow path communicates with the supply port,
The support member has a first partition member extending along the supply port at a position facing a region between two adjacent supply ports on the element substrate,
The liquid discharge head, wherein the distance between the first partition member and the element substrate varies depending on the position in the extending direction of the first partition member.   The liquid ejection head according to claim 1, wherein first recesses are formed at both ends of the surface of the first partition member facing the element substrate in the extending direction. The support member has a joining region joined to the element substrate on both sides of the first partition member in the extending direction,
The liquid ejection head according to claim 1, wherein a second recess is formed in the bonding region.   4. The liquid ejection head according to claim 2, wherein the first partition member is flat except for the portion where the recess is provided on the surface facing the element substrate.   The surface of the first partition member facing the element substrate has an inclination such that the distance becomes shorter as it approaches the central portion of the supply port in the extending direction. The liquid ejection head according to any one of 1.   The surface of the first partition member facing the element substrate has the shortest distance at a specific position between the central portion and both ends of the supply port in the extending direction, and the central portion extends from the central portion. 4. The liquid ejection head according to claim 1, wherein the liquid ejection head has an inclination such that the distance becomes longer as it approaches the portion and the both ends. The support member has a joining region joined to the element substrate on both sides of the first partition member in the extending direction,
7. The liquid ejection head according to claim 5, wherein a distance between the support member and the element substrate in the bonding area is shorter than the distance at both ends of the supply port.   A space between the first partition member and the element substrate is filled with an adhesive layer formed of an adhesive that bonds the support member and the element substrate. The liquid ejection head according to claim 1.   8. The liquid ejection head according to claim 1, wherein a gap is provided between the first partition member and the element substrate. The length of the first partition member in the penetrating direction from the first surface to the second surface is shorter than the length of the flow path in the penetrating direction,
The liquid ejection head according to claim 1, wherein a surface of the first partition member facing the element substrate and the first surface are provided on the same plane. .   The length of the first partition member in the penetrating direction from the first surface to the second surface is substantially the same as the length of the flow path in the penetrating direction. 9. The liquid ejection head according to any one of items 9. The support member has a second partition member extending in a direction substantially orthogonal to the first partition member in the flow path,
A surface of the second partition member opposite to the surface facing the element substrate and the second surface of the support member are on the same plane;
12. The length of the second partition member in the penetrating direction from the first surface to the second surface is shorter than the length of the flow path in the penetrating direction. The liquid ejection head according to claim 1.   The liquid ejection head according to claim 12, wherein the second partition member is provided between the central portion and both end portions of the first partition member in the extending direction.   14. The liquid ejection head according to claim 12, wherein the second partition member is provided at a central portion of the first partition member in the extending direction.   A third recess is formed at a position of the surface of the first partition member facing the element substrate, the position facing the second partition member provided in the central portion of the first partition member. The liquid ejection head according to claim 14, wherein   A liquid ejecting apparatus comprising the liquid ejecting head according to any one of claims 1 to 15.

Images