Liquid ejection head, liquid ejection unit, and liquid ejection device

Abstract

To provide a liquid discharge head which can inhibit occurrence of distortion at an exterior component and an interior component.SOLUTION: A liquid discharge head 1 includes: a passage component 3 serving as an interior component; and an exterior cover 2 serving as an exterior component which covers the passage component 3. The passage component 3 is joined to one surface and the other surface, which face each other through the passage component 3, of the exterior cover 2. The passage component 3 includes: a head part 3a serving as a first member; and a liquid supply part 3b serving as a second member which is connected to the head part 3a so as to be movable relative to the head part 3a in a direction orthogonal to a joint surface, which is joined to the exterior cover 2, of the passage component 3.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a liquid ejection head, a liquid ejection unit, and an apparatus for ejecting liquid. [Background technology]

[0002] 2. Description of the Related Art Conventionally, a liquid ejection head is known that includes an internal component and an exterior component that covers the internal component.

[0003] Patent Document 1 describes a liquid ejection head that includes internal components such as liquid supply paths and liquid chambers, as well as an exterior cover member that covers electrical components such as a circuit board. Summary of the Invention [Problem to be solved by the invention]

[0004] However, there is a risk that distortion may occur in at least one of the exterior and interior components. [Means for solving the problem]

[0005] In order to solve the above-mentioned problems, the present invention provides a method for manufacturing a vehicle comprising: an internal component; and an exterior component covering the internal component; the internal component being joined to one surface and the other surface of the exterior component facing each other via the internal component; the internal component being comprised of a first member and a second member connected to the first member so as to be movable relative to the first member in a direction perpendicular to a joining surface of the internal component joined to the exterior component. a second internal part fixed to the second member and a member different from the second member, and the internal part has a third member connected to the second member so as to be movable relative to the second member in a direction perpendicular to the joining surface; It is characterized by the following. [Effects of the Invention]

[0006] According to the present invention, it is possible to suppress the occurrence of distortion in exterior and interior parts. [Brief explanation of the drawings]

[0007] [Figure 1]FIG. 1 is a schematic cross-sectional view of a liquid ejection head according to an embodiment of the present invention. [Figure 2] FIG. 2 is a schematic perspective view of a flow path component of the liquid ejection head. [Figure 3] 1A is a schematic cross-sectional view showing an exterior cover and flow path components of a conventional liquid ejection head, and FIG. 1B is a schematic cross-sectional view showing the exterior cover and flow path components of a conventional liquid ejection head after thermal expansion. [Figure 4] 10A and 10B are diagrams showing an example of distortion after thermal expansion of a conventional liquid ejection head. [Figure 5] 1A is a schematic cross-sectional view showing an exterior cover and flow path components of a liquid ejection head according to this embodiment, and FIG. 1B is a schematic cross-sectional view showing the exterior cover and flow path components of the liquid ejection head after thermal expansion. [Figure 6] FIG. 10 is a schematic cross-sectional view of a liquid ejection head in which a flow path component and an exterior cover are joined with an adhesive. [Figure 7] FIG. 10 is a schematic cross-sectional view of a liquid ejection head in which a sealing member is provided at a joint portion. [Figure 8] FIG. 10 is a schematic cross-sectional view showing a first modified example of the flow path component. [Figure 9] FIG. 10 is a schematic cross-sectional view showing a second modified example of the flow path component. [Figure 10] FIG. 10 is a schematic cross-sectional view showing an embodiment of Modification 2 in which an electrical board is fixed to a head unit and a lower liquid supply unit. [Figure 11] 10A and 10B are diagrams illustrating a problem in which the connection between the lower liquid supply unit and the upper liquid supply unit comes off when the upper liquid supply unit is joined to the exterior cover. [Figure 12] 10 is a schematic cross-sectional view showing an embodiment of a second modified example in which a first slippage prevention portion and a second slippage prevention portion are provided. FIG. [Figure 13] FIG. [Figure 14] FIG. [Figure 15] FIG. [Figure 16] FIG. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, an embodiment in which the present invention is applied to a liquid ejection head of an inkjet recording apparatus as an image forming apparatus that ejects liquid will be described. The present invention is not limited to the embodiments shown below, but may be modified, added, modified, deleted, or otherwise altered within the scope of what a person skilled in the art can conceive, and any aspect of the present invention is within the scope of the present invention as long as it exhibits the functions and effects of the present invention.

[0009] FIG. 1 is a schematic cross-sectional view of a liquid ejection head 1 of this embodiment, and FIG. 3 is a schematic perspective view of a flow path component 3. As shown in FIG. The liquid ejection head 1 includes a flow path component 3 as an internal component, an electrical board 4 as a second internal component, and an exterior cover 2 as an exterior component that covers these components.

[0010] The flow path component 3 has a head portion 3a as a first member and a liquid supply portion 3b as a second member. The liquid supply portion 3b is connected to the head portion 3a by a connecting portion 10 so as to be movable relative to the head portion 3a in the vertical direction. The head unit 3a has a nozzle surface 31 on which a plurality of nozzles 31a are arranged, individual liquid chambers to which the nozzles 31a communicate, a common liquid chamber that supplies liquid to the individual liquid chambers, a pressure unit that pressurizes the liquid in each individual liquid chamber, etc. Four nozzle rows are provided in a direction perpendicular to the plane of the paper in FIG.

[0011] The liquid supply unit 3b has a supply path leading to the common liquid chamber of the head unit 3a, and a supply port 32 that is provided to penetrate the exterior cover 2 and to which a tube for supplying liquid from a tank that stores the liquid is detachably connected. The outer surface of the supply port 32 is provided with a barb to prevent the attached tube from coming loose. As shown in FIG. 3, four supply ports 32 are arranged on the top surface of the flow path part 3.

[0012] The liquid supplied to the supply port 32 is supplied from the supply path of the liquid supply unit 3b via the connecting unit 10 to the common liquid chamber of the head unit 3a, and then from the common liquid chamber to the individual liquid chambers. Of the two supply ports, the color of the liquid supplied from one supply port is different from the color of the liquid supplied from the other supply port. The liquid supplied from one supply port is ejected from the nozzles of one of the two nozzle rows, and the liquid supplied from the other supply port is ejected from the nozzles of the other nozzle row.

[0013] The connecting portion 10 that connects the head portion 3a and the liquid supply portion 3b is composed of a cylindrical connecting insertion portion 35 that protrudes from the upper surface of the head portion 3a, and a circular connecting recess 34 that is provided on the lower surface of the liquid supply portion 3b and into which the connecting insertion portion 35 of the head portion 3a is inserted. A communication passage that leads to the common liquid chamber is formed in the center of the connecting insertion portion 35, and a supply path is connected to the bottom surface of the connecting recess 34.

[0014] The inner diameter of the connecting recess 34 is larger than the outer diameter of the connecting insertion part 35, and an O-ring 33 is provided as a sealing member that fills the gap between the inner peripheral surface of the connecting recess 34 and the outer peripheral surface of the connecting insertion part 35. This O-ring 33 seals the liquid that has flowed from the supply path of the liquid supply part 3b to the connecting recess 34, preventing leakage of the liquid. The liquid that has flowed into the connecting recess 34 flows through the communication path of the connecting insertion part 35 to the common liquid chamber.

[0015] It is preferable to provide a groove into which the O-ring 33 fits on the inner peripheral surface of the connecting recess 34 or the connecting insertion portion 35. This allows the O-ring 33 to be fitted into either the connecting recess 34 or the connecting insertion portion 35, and the connecting insertion portion 35 to be inserted into the connecting recess 34, making assembly easier.

[0016] It is also preferable that the upper surface of the connecting insertion part 35 is a tapered surface that slopes downward toward the communication passage provided in the center of the connecting insertion part 35. This allows liquid adhering to the upper surface of the connecting insertion part 35 to flow into the communication passage without flowing down from the supply path of the connecting recess 34 into the communication passage in the center of the connecting insertion part 35.

[0017] It is also preferable to provide a connecting recess 34 in the head portion 3a and a connecting insertion portion 35 in the liquid supply portion 3b. By providing the connecting recess 34 in the head portion 3a, the sealing portion of the O-ring 33 can be located above the portion where the liquid is transferred from the supply path of the liquid supply portion 3b to the communication path of the head portion 3a. This prevents the liquid from flowing down into the sealing portion of the O-ring 33, improving the liquid sealing performance.

[0018] In this embodiment, the connecting portion 10 has a connecting recess 34 and a connecting insertion portion 35 that is inserted into this connecting recess 34, and the connecting insertion portion 35 is configured to be movable within a predetermined range within the connecting recess 34. This allows the liquid supply portion 3b to be connected to the head portion 3a so as to be movable relative to the head portion 3a.

[0019] The electrical board 4, which serves as a second internal component, is connected to an actuator provided in the pressure section of the head unit 3a and has a drive circuit formed thereon for driving the actuator. An FFC (flexible flat cable) 5 is connected to the electrical board 4 for transmitting power and drive signals from the outside to the electrical board 4. The electrical board 4 is disposed adjacent to the side of the head unit 3a and is secured to the bottom surface of the exterior cover 2 with screws 6. Alternatively, the electrical board 4 may be fixed to the head unit 3a. By fixing the electrical board 4 to the head unit 3a, it is possible to prevent the electrical board 4 from interfering with thermal expansion of the head unit 3a in the left-right direction in the figure.

[0020] The exterior cover 2 has a box-shaped first cover member 2a that is open at the bottom, and a plate-shaped second cover member 2b that is joined to the first cover member 2a with screws 6 so as to close the opening of the first cover member 2a.

[0021] An opening 21a for exposing the nozzle surface 31 of the head unit 3a is formed in the second cover member 2b that forms the bottom of the exterior cover 2. In addition, an opening 21b for the supply port 32 of the liquid supply unit 3b to pass through and an opening 21c for the FFC 5 to pass through are formed in the upper surface of the first cover member 2a that forms the ceiling of the exterior cover 2.

[0022] As shown in FIG. 1 , the lower surface of the flow path component 3, which is the joining surface, is joined to the exterior cover 2 with screws 6 near the opening 21a through which the nozzles 31a of the nozzle surface 31 are exposed, and the lower surface of the flow path component 3 is in close contact with the bottom surface of the exterior cover 2, which is the joined surface. This prevents droplets, dust, dirt, and the like from entering the exterior cover through the opening 21a. Furthermore, the upper surface of the flow path component 3, which is the joining surface, is joined to the exterior cover with screws 6 near the opening 21b through which the supply port 32 passes, and the upper surface of the flow path component 3 is in close contact with the ceiling surface of the exterior cover 2, which is the joined surface. This prevents droplets, dust, dirt, and the like from entering the exterior cover through the opening 21b. This prevents droplets, dust, dirt, and the like from adhering to the electrical board 4 arranged inside the exterior cover, and thus prevents short circuits and the like.

[0023] The exterior cover 2 is made of PPS (polyphenylene sulfide) containing glass filler, as it is required to be aesthetically pleasing and strong. On the other hand, the flow path component 3 (head portion 3a and liquid supply portion 3b) is made of PP (polypropylene) containing no glass filler, as it is required to be liquid-wettable, clean, low-cost, and resistant to chemical attack by ink. In this way, the exterior cover 2 and the flow path component 3 are made of different materials to meet the required conditions. As a result, the flow path component 3 has a higher linear expansion coefficient in a high-temperature environment, and the height fluctuation of the flow path component 3 is greater than the height fluctuation of the exterior cover 2 in a high-temperature environment.

[0024] FIG. 3(a) is a schematic cross-sectional view showing an exterior cover of a conventional liquid ejection head and a flow path component, and (b) is a schematic cross-sectional view showing the exterior cover of the conventional liquid ejection head after thermal expansion and the flow path component. As shown in FIG. 3(a), in the flow path component of the conventional liquid ejection head, a liquid supply portion 3b was fixed to the upper surface of a head portion 3a with an adhesive or the like, and the liquid supply portion 3b was connected to the head portion 3a so as not to be relatively movable. Also in the conventional liquid ejection head, in the vicinity of an opening portion 21a for exposing a nozzle surface, the lower surface of the flow path component 3 was joined to the exterior cover with screws 6, and the lower surface of the flow path component 3 was brought into close contact with the bottom surface of the exterior cover 2. Therefore, the height from the lower surface to the upper surface of the flow path component 3, which is the joining surface joined to the exterior cover, was made the same as the height from the bottom surface to the ceiling surface of the exterior cover, which is the joined surface.

[0025] As shown in FIG. 3(b), the exterior cover 2 made of PPS containing a glass filler changes in height (height from the bottom surface to the ceiling surface) between the joined surfaces from D to D' due to thermal expansion in a high-temperature environment. On the other hand, the flow path component 3 made of PP having a larger linear expansion coefficient than the exterior cover 2 changes in height (height from the lower surface to the upper surface) between the joined surfaces from D to D'' (D' < D'') due to thermal expansion in a high-temperature environment. Thus, the flow path component 3 has a larger dimensional change due to thermal expansion than the exterior cover 2. However, the flow path component 3 housed with its upper and lower surfaces joined to the exterior cover 2 is suppressed in dimensional change by the exterior cover 2 at the joining portions around the opening portions 21a, 21b of the exterior cover 2. As a result, as shown in FIG. 4, both the upper surface portion and the lower surface portion of the exterior cover 2 and the upper surface portion and the lower surface portion of the flow path component 3 are distorted so that the center in the left-right direction in the figure protrudes. Thus, when the flow path component 3 is distorted, the nozzle surface 31 is distorted, and the liquid ejected from the nozzle does not land at a specified position. Further, when the liquid ejection head 1 is distorted as shown in FIG. 4, an appearance defect occurs. Furthermore, when the flow path component 3 is joined to the exterior cover 2 with an adhesive, there is a possibility that the adhesion may be peeled off due to the distortion as shown in FIG. 3, and a problem may occur in that the flow path component 3 rattles within the exterior cover 2.

[0026] Figure 5(a) is a schematic cross-sectional view showing the outer cover 2 and flow path components 3 of the liquid ejection head of this embodiment, and Figure 5(b) is a schematic cross-sectional view showing the outer cover and flow path components of the liquid ejection head after thermal expansion. As shown in FIG. 5(a), in the flow path part 3 of this embodiment, the liquid supply part 3b is connected to the head part 3a so as to be movable in the up and down direction relative to the head part 3a.

[0027] 5(a), in this embodiment, when the height from the lower surface, which is the joining surface of the flow path part 3 joined to the exterior cover 2, to the upper surface is set to be the same as the height D from the bottom surface, which is the joined surface of the exterior cover, to the ceiling surface, a gap d is formed between the upper surface of the head part 3a and the lower surface of the liquid supply part 3b. That is, in this embodiment, the gap d is formed between the upper surface of the head part 3a and the lower surface of the liquid supply part 3b, and the lower and upper surfaces of the flow path part 3 are joined to the exterior cover, and the flow path part 3 is housed within the exterior cover.

[0028] As shown in FIG. 5(b), the height between the joined surfaces (height from the bottom surface to the ceiling surface) of the exterior cover 2 changes from D to D' due to thermal expansion, as in the conventional case. Meanwhile, the flow path component 3 attempts to thermally expand in the height direction by (D''-D') more than the exterior cover 2. However, because the exterior cover 2 actually holds it back, the height between the joined surfaces of the flow path component 3 (height from the bottom surface to the top surface) is held to D'. The extra thermal expansion of the flow path component 3 (D''-D') is absorbed by narrowing the gap d between the top surface of the head portion 3a and the bottom surface of the liquid supply portion 3b to d'. As a result, stress can be suppressed at the joint between the exterior cover 2 and the flow path component 3 in a high-temperature environment, and distortion of the liquid ejection head 1 in a high-temperature environment can be suppressed. This can suppress deviation of the landing position from the specified position and poor appearance in a high-temperature environment.

[0029] Although the above description has been given of a case where the linear expansion coefficient of the flow path component 3 is greater than that of the exterior cover 2, the configuration of this embodiment can also be applied to a case where the linear expansion coefficient of the flow path component 3 is smaller than that of the exterior cover 2. When the linear expansion coefficient of the flow path component 3 is smaller than that of the exterior cover 2, the conventional configuration shown in FIG. 3 results in the liquid ejection head 1 being distorted into a concave shape at the top and bottom, contrary to the configuration shown in FIG. 4 . On the other hand, according to this embodiment, the liquid supply unit 3b of the flow path component 3 is configured to be movable vertically relative to the head unit 3a. This allows the liquid supply unit 3b to move relative to the head unit 3a during thermal expansion, widening the gap d between the head unit 3a and the liquid supply unit 3b. This prevents stress from occurring at the joint between the exterior cover 2 and the flow path component 3 in a high-temperature environment, thereby preventing the liquid ejection head 1 from being distorted in a high-temperature environment. If the linear expansion coefficient of the flow path part 3 is smaller than that of the exterior cover 2, the gap d between the head part 3a and the liquid supply part 3b may be zero (d=0) initially (at room temperature).

[0030] Furthermore, for example, due to manufacturing errors, there may be a difference in the height dimension between the joined surfaces of the exterior cover 2 (height from the bottom surface to the ceiling surface) and the height dimension between the joined surfaces of the flow path component 3 (height from the lower surface to the upper surface). In such a case, in the conventional configuration shown in FIG. 3, distortion occurs in the exterior cover 2 and the flow path component 3 as shown in FIG. 4. On the other hand, in this embodiment, such dimensional differences due to manufacturing errors can be absorbed by the liquid supply unit 3b moving vertically relative to the head unit 3a, and distortion of the exterior cover 2 and the flow path component 3 due to dimensional differences between the exterior cover and the head unit caused by manufacturing errors can also be suppressed.

[0031] In the above description, the flow path part 3 is joined to the exterior cover 2 by the screws 6, but as shown in FIG. 6, the flow path part 3 may be joined to the exterior cover 2 by an adhesive 7 as a sealant. When the exterior cover 2 and the flow path part 3 are joined with the screws 6, a small gap may be generated between the exterior cover 2 and the flow path part 3. Therefore, liquid droplets adhering to the part of the flow path part 3 exposed from the opening 21b of the exterior cover 2 may eventually enter the interior of the exterior cover 2 through the small gap at the joined part.

[0032] On the other hand, as shown in Fig. 6, by joining the exterior cover 2 and the flow path part 3 with an adhesive 7, it is possible to completely seal the gap at the joined part and prevent liquid from entering the exterior cover 2 through the joined part. Furthermore, as shown in Fig. 6, by also joining the first cover member 2a and the second cover member 2b with an adhesive 7, it is possible to prevent liquid from entering the exterior cover through the gap between the first cover member 2a and the second cover member 2b. Furthermore, as shown in FIG. 6, by filling the opening 21c of the exterior cover 2 through which the FFC 5 passes with adhesive 7, it is possible to prevent the intrusion of droplets, dust, and the like through this opening 21c.

[0033] On the other hand, as shown in FIG. 1 , joining the exterior cover 2 and the flow path component 3 with screws 6 can provide the following advantages. Specifically, the inner diameter of the through hole through which the screw 6 passes in the exterior cover 2 is made larger than the outer diameter of the body of the screw 6, and the lateral dimensional error between the flow path component 3 and the exterior cover 2 that occurs during thermal expansion can be absorbed by the gap between the through hole and the body of the screw. This has the advantage of reducing the shear stress applied to the joint in a high-temperature environment compared to joining the exterior cover 2 and the flow path component 3 with adhesive 7. Furthermore, the gap between the through hole in the exterior cover 2 and the body of the screw is blocked by the head of the screw, preventing the intrusion of liquids, dust, and the like through the gap.

[0034] Furthermore, bonding with the adhesive 7 has the property of shrinking when hardened, depending on the adhesive 7, and variations in the shrinkage may cause distortion in the flow path component 3 or the exterior cover 2, or cause bonding defects. In contrast, bonding the exterior cover 2 and the flow path component 3 with the screws 6 has the advantage of preventing the above-mentioned distortion and bonding defects that occur when bonding with the adhesive 7.

[0035] 7, a sealing member 8 made of an elastic material such as rubber may be provided as a sealant at the joint between the exterior cover 2 and the flow path part 3, and the exterior cover 2 and the flow path part 3 may be joined with screws 6. With this configuration, it is possible to completely seal the gap at the joint and prevent liquid from entering the exterior cover 2 through the joint.

[0036] The sealing member may be any member that can fill the gap between the exterior cover 2 and the flow path part 3 at the joining location, and may be an adhesive 7. Joining the exterior cover 2 and the flow path part 3 with an adhesive and screws 6 can prevent the above-mentioned problems caused by shrinkage of the adhesive when hardened.

[0037] In addition, by providing a sealing member 8 at the fixed location between the first cover member 2a and the second cover member 2b and joining them with screws 6, it is possible to prevent liquid from entering the exterior cover through the gap between the first cover member 2a and the second cover member 2b.

[0038] In the above description, the flow path component 3 is joined to the exterior cover 2 by fixing the exterior cover 2 and the flow path component 3 with the adhesive 7 or the screws 6. However, it is sufficient that the flow path component 3 contacts the exterior cover 2 so as to prevent the intrusion of droplets, dust, and the like into the exterior cover through the openings 21 a and 21 b. Therefore, if high adhesion can be obtained, the flow path component 3 may be joined to the exterior cover 2 simply by contacting the flow path component 3 with the periphery of the openings 21 a and 21 b of the exterior cover 2, without fixing with the adhesive 7 or the screws 6. When the linear expansion coefficient of the flow path component 3 is larger than the linear expansion coefficient of the exterior cover 2, as in this embodiment, the bond between the flow path component 3 and the exterior cover 2 is maintained, and the liquid supply portion 3 b of the flow path component 3 can be moved relative to the head portion 3 a, thereby suppressing distortion of the flow path component 3 and the exterior cover 2.

[0039] On the other hand, if the linear expansion coefficient of the flow path part 3 is smaller than that of the exterior cover 2, it is preferable to join the flow path part 3 to the exterior cover 2 by fixing them with adhesive 7 or screws 6. This is because if the flow path part 3 is joined by simply contacting it with the periphery of the openings 21a and 21b of the exterior cover 2, the joining cannot be maintained in a high-temperature environment, and a gap will be formed between the flow path part 3 and the exterior cover 2. As a result, it will not be possible to prevent liquids and the like from entering the exterior cover.

[0040] In a configuration in which the linear expansion coefficient of the flow path component 3 is smaller than that of the exterior cover 2 and they are joined by fixing with screws 6 or the like, when a difference in thermal expansion between the exterior cover 2 and the flow path component 3 causes a difference in dimension in the vertical direction, distortion is suppressed as follows: That is, the liquid supply unit 3b moves relative to the head unit 3a in the direction in which the gap between the liquid supply unit 3b and the head unit 3a widens, and the vertical dimension of the flow path component 3 matches the dimension of the exterior cover 2. This makes it possible to suppress distortion in the exterior cover 2 and the flow path component 3.

[0041] In the above description, the flow path part 3 is joined to the exterior cover 2 around the openings thereof for the purpose of preventing droplets, dust, and the like from entering the interior of the exterior cover through the openings 21a and 21b, but this is not limiting. For example, the flow path part 3 may be joined to the exterior cover 2 for the purpose of preventing rattling of the flow path part 3 inside the exterior cover or for the purpose of positioning. When the flow path part 3 is joined to the exterior cover 2 for a purpose other than preventing droplets, dust, and the like from entering the interior of the exterior cover through the openings 21a and 21b, the joining location between the flow path part 3 and the exterior cover 2 does not have to be around the opening 21a.

[0042] FIG. 8 is a schematic cross-sectional view showing a first modification of the flow path component 3. As shown in FIG. 8, the flow path part of this modification has guide portions 36 that guide the movement of the liquid supply portion 3b relative to the head portion 3a. The guide portions 36 make the head portion 3a longer in the left-right direction in the figure than the liquid supply portion 3b, and extend upward from both left-right ends of the head portion 3a to face the side surfaces of the liquid supply portion 3b. As a result, the liquid supply portion 3b moves up and down relative to the head portion 3a while the side surfaces of the liquid supply portion 3b are guided by the guide portions 36.

[0043] Since the connecting portion 10 is sealed with an elastically deformable O-ring 33, it is preferable that the axial misalignment between the central axis of the connecting insertion portion 35 and the central axis of the connecting recess 34 is small in order to ensure that the connecting portion 10 is sealed against liquid.

[0044] By providing guide portion 36 as in Modification 1, it is possible to prevent liquid supply portion 3b from shifting left and right in the figure with respect to head portion 3a when liquid supply portion 3b moves up and down relative to head portion 3a. This makes it possible to prevent axial misalignment between the central axis of connecting insertion portion 35 and the central axis of connecting recess 34, and O-ring 33 can stabilize the sealing performance of the connecting portion.

[0045] For example, head unit 3a may be made longer than liquid supply unit 3b in the direction perpendicular to the plane of the paper in Fig. 8, and a guide unit may be further provided on the head unit, facing the side surface of liquid supply unit 3b perpendicular to the plane of the paper. This makes it possible to prevent liquid supply unit 3b from shifting relative to head unit 3a in the direction perpendicular to the plane of the paper in Fig. 8 when liquid supply unit 3b moves vertically relative to head unit 3a.

[0046] 8, guide portion 36 is provided on head portion 3a, but it may also be provided on liquid supply portion 3b. Furthermore, it is not limited to the configuration shown in FIG. 8 as long as it can guide the relative vertical movement of liquid supply portion 3b with respect to head portion 3a. For example, a groove may be provided in guide portion 36 of the head portion, and a guide protrusion that fits into this groove may be provided on the liquid supply portion.

[0047] FIG. 9 is a schematic cross-sectional view showing a second modification of the flow path part 3. As shown in FIG. 9, the flow path part 3 is divided into a lower liquid supply part 3b1 as a second member and an upper liquid supply part 3b2 as a third member. That is, in the flow path part 3 of the second modification, the head part 3a, the lower liquid supply part 3b1, and the upper liquid supply part 3b2 are configured as three members. The structure of first connecting portion 10a connecting lower liquid supply portion 3b1 and head portion 3a, and the structure of second connecting portion 10b connecting lower liquid supply portion 3b1 and upper liquid supply portion 3b2, are similar to that of connecting portion 10 described above. That is, a connecting recess is provided on one side of the connecting portion, and a connecting insertion portion inserted into the connecting recess is provided on the other side. The gap between the inner peripheral surface of the connecting recess and the outer peripheral surface of the connecting insertion portion is sealed with O-ring 33. By configuring first connecting portion 10a in this way, lower liquid supply portion 3b1 can be connected to head portion 3a so as to be movable relative to head portion 3a. Furthermore, by configuring second connecting portion 10b in this way, upper liquid supply portion 3b2 can be connected to lower liquid supply portion 3b1 so as to be movable relative to lower liquid supply portion 3b1. In addition, in this modified example 2, the electrical circuit board 4 is fixed to the second cover member 2b and the lower liquid supply portion 3b1 with screws 6.

[0048] In the liquid ejection head shown in FIG. 1 , the electrical board 4 is fixed only to the second cover member 2b. However, because the thin electrical board 4 is fixed only in one place, the orientation of the electrical board 4 is unstable. Therefore, it is preferable to increase the number of fixing points for the electrical board 4 by fixing the electrical board 4 to the second cover member 2b and the flow path component 3 disposed adjacent to the electrical board 4. However, due to the difference in the linear expansion coefficient between the electrical board 4 and the flow path component 3, the dimensional change of the electrical board 4 due to thermal expansion in a high-temperature environment differs from the dimensional change of the flow path component 3. As a result, distortion occurs in the electrical board 4, which has a lower rigidity than the flow path component 3, which may cause problems such as poor electrical contact between the electrical board 4 and the FFC 5.

[0049] 9, the flow path component 3 is configured with three members that are relatively movable relative to one another, and the electrical board 4 is configured to be fixed to the lower liquid supply unit 3b1, which is located in the vertical center of the three members, and to the second cover member 2b. As a result, in a high-temperature environment, the lower liquid supply unit 3b1 moves relative to the head unit 3a and the upper liquid supply unit 3b2 in response to thermal expansion of the electrical board 4. This prevents distortion of the electrical board 4 and prevents problems such as poor electrical contact between the electrical board 4 and the FFC 5.

[0050] On the other hand, the vertical dimensional difference between the flow path part 3 and the exterior cover 2 after thermal expansion due to the difference in the linear expansion coefficient between the flow path part 3 and the exterior cover 2, and the dimensional difference due to manufacturing errors are absorbed by the head part 3a and the upper liquid supply part 3b2 moving relative to the lower liquid supply part 3b1, thereby preventing distortion of the exterior cover 2 and the flow path part 3.

[0051] Furthermore, the liquid ejection head of this embodiment can also suppress distortion of the exterior cover 2 and the flow path component 3 when, for example, the vertical dimension of the electrical board 4 differs from the specified dimension due to manufacturing errors. That is, if the vertical dimension of the electrical board 4 differs from the specified dimension, the lower liquid supply unit 3b1 moves relative to the head unit 3a and the upper liquid supply unit 3b2 when the electrical board 4 attached to the lower liquid supply unit 3b1 is screwed to the exterior cover 2. This makes it possible to absorb the vertical dimensional error of the electrical board 4, and suppress distortion of the electrical board 4 due to the vertical dimensional error of the electrical board 4.

[0052] 10, the electrical board 4 may be fixed to the head portion 3a and the lower liquid supply portion 3b1. This makes it possible to prevent the electrical board 4 from being distorted due to the difference in thermal expansion between the flow path component 3 and the exterior cover 2 in the left-right direction in the figure.

[0053] When the flow path part 3 is attached to the exterior cover 2, the upper liquid supply part 3b2 may come off from the lower liquid supply part 3b1, or the head part 3a may come off from the lower liquid supply part 3b1.

[0054] In the configurations shown in FIGS. 9 and 10, the electrical board 4 is attached to the lower liquid supply unit 3b1, and the vertical position of the lower liquid supply unit 3b1 is determined by the electrical board 4. This allows the gap between the head unit 3a and the lower liquid supply unit 3b1 and the gap between the head unit 3a and the upper liquid supply unit 3b2 to be approximately equal. However, as shown in FIG. 11, in a configuration in which the electrical board 4 is not attached to the lower liquid supply unit 3b1, the vertical position of the lower liquid supply unit 3b1 cannot be determined. As a result, the lower liquid supply unit 3b1 may be assembled to the head unit 3a with a narrow gap between them. In this case, there is a risk that the connection between the lower liquid supply unit 3b1 and the upper liquid supply unit 3b2 may come loose when the upper liquid supply unit 3b2 is joined to the exterior cover 2 with the screws 6.

[0055] 12, it is preferable to provide a first detachment prevention part 37 that prevents detachment of the lower liquid supply part 3b1 of the head part 3a, and a second detachment prevention part 38 that prevents detachment of the lower liquid supply part 3b1 and the upper liquid supply part 3b2. The first detachment prevention part 37 and the second detachment prevention part 38 are provided on both the left and right sides of the flow path part 3 in the drawing.

[0056] The first removal prevention part 37 is composed of a first removal prevention protrusion 37b extending horizontally from the lower end of the lower liquid supply part 3b1 and a first hook part 37a extending upward from the upper end of the head part 3a. The claw part at the tip of the first hook part 37a faces the first removal prevention protrusion 37b from above in the vertical direction.

[0057] Second removal prevention portion 38 is composed of second removal prevention protrusion 38b extending horizontally from the upper end of lower liquid supply portion 3b1 and second hook portion 38a extending downward from the lower end of upper liquid supply portion 3b2. The claw portion at the tip of second hook portion 38a faces second removal prevention protrusion 38b from below in the vertical direction.

[0058] The provision of first removal prevention portion 37 can prevent head portion 3a from being removed from lower liquid supply portion 3b1 when, for example, assembling flow path part 3 to exterior cover 2, thereby preventing the need for reassembly. Furthermore, the provision of second removal prevention portion 38 can prevent upper liquid supply portion 3b2 from being removed from lower liquid supply portion 3b1 when, for example, assembling flow path part 3 to exterior cover 2, thereby preventing the need for reassembly.

[0059] Furthermore, when lower liquid supply unit 3b1 is assembled to head unit 3a with a narrow gap between head unit 3a and lower liquid supply unit 3b1, and upper liquid supply unit 3b2 is joined to exterior cover 2 with screw 6 in this assembled state, the following occurs. That is, as screw 6 is threaded, upper liquid supply unit 3b2 moves upward, and the claw portion at the tip of second hook portion 38a abuts second removal prevention protrusion 38b before the connection between upper liquid supply unit 3b2 and lower liquid supply unit 3b1 is released. Then, the claw portion at the tip of second hook portion 38a lifts lower liquid supply unit 3b1, and lower liquid supply unit 3b1 moves upward together with upper liquid supply unit 3b2. As a result, upper liquid supply unit 3b2 can be joined to the exterior cover with screw 6 without releasing the connection between upper liquid supply unit 3b2 and lower liquid supply unit 3b1.

[0060] Furthermore, the portion of first hook portion 37a other than the claw portion faces first removal prevention protrusion 37b from the outer side in the left-right direction. This allows first hook portion 37a to function as a guide portion that guides the vertical movement of lower liquid supply portion 3b1 relative to head portion 3a. This makes it possible to prevent axial misalignment between the central axis of connecting recess 34 of lower liquid supply portion 3b1 and the central axis of connecting insertion portion 35 of head portion 3a, and allows O-ring 33 to stabilize the sealing of the connecting portion.

[0061] Similarly, second hook portion 38a of second loss prevention portion 38 functions as a guide portion that guides the relative vertical movement of upper liquid supply portion 3b2 with respect to lower liquid supply portion 3b1. This makes it possible to prevent axial misalignment between the central axis of connecting recess 34 of upper liquid supply portion 3b2 and the central axis of connecting insertion portion 35 of lower liquid supply portion 3b1, and allows O-ring 33 to stabilize the sealing of the connecting portion.

[0062] Next, an example of a liquid ejection device according to the present invention will be described with reference to Figures 13 and 14. Figure 13 is an explanatory plan view of the main parts of the device, and Figure 14 is an explanatory side view of the main parts of the device.

[0063] This device is a serial type device, and a carriage 403 is moved back and forth in the main scanning direction by a main scanning movement mechanism 493. The main scanning movement mechanism 493 includes a guide member 401, a main scanning motor 405, a timing belt 408, etc. The guide member 401 is hung between left and right side plates 491A and 491B, and movably holds the carriage 403. The main scanning motor 405 then moves the carriage 403 back and forth in the main scanning direction via a timing belt 408 hung between a drive pulley 406 and a driven pulley 407.

[0064] This carriage 403 is equipped with a liquid ejection unit 440 that integrates a liquid ejection head 404 according to the present invention and a head tank 441. The liquid ejection head 404 of the liquid ejection unit 440 ejects liquid of each color, for example, yellow (Y), cyan (C), magenta (M), and black (K). The liquid ejection head 404 is mounted with a nozzle row made up of multiple nozzles arranged in a sub-scanning direction perpendicular to the main scanning direction, and the ejection direction facing downward.

[0065] The liquid stored in the liquid cartridge 450 is supplied to the head tank 441 by a supply mechanism 494 for supplying the liquid stored outside the liquid ejection head 404 to the liquid ejection head 404 .

[0066] The supply mechanism 494 is composed of a cartridge holder 451 which is a filling section to which the liquid cartridge 450 is attached, a tube 456, a liquid delivery unit 452 including a liquid delivery pump, etc. The liquid cartridge 450 is detachably attached to the cartridge holder 451. The liquid is delivered from the liquid cartridge 450 to the head tank 441 by the liquid delivery unit 452 via the tube 456.

[0067] This device is provided with a transport mechanism 495 for transporting paper 410. The transport mechanism 495 includes a transport belt 412, which is a transport means, and a sub-scanning motor 416 for driving the transport belt 412.

[0068] The conveyor belt 412 attracts the paper 410 and conveys it at a position facing the liquid ejection head 404. The conveyor belt 412 is an endless belt that is stretched between a conveyor roller 413 and a tension roller 414. The paper can be attracted by electrostatic attraction or air suction.

[0069] The conveyor belt 412 moves in a circular motion in the sub-scanning direction when the conveyor roller 413 is rotationally driven by a sub-scanning motor 416 via a timing belt 417 and a timing pulley 418 .

[0070] Furthermore, a maintenance and recovery mechanism 420 for performing maintenance and recovery of the liquid ejection head 404 is disposed on one side of the conveyor belt 412 on one side of the carriage 403 in the main scanning direction.

[0071] The maintenance and recovery mechanism 420 is made up of, for example, a cap member 421 that caps the nozzle surface (the surface on which the nozzles are formed) of the liquid ejection head 404, a wiper member 422 that wipes the nozzle surface, and the like.

[0072] The main scanning movement mechanism 493, the supply mechanism 494, the maintenance and recovery mechanism 420, and the transport mechanism 495 are attached to a housing including side plates 491A and 491B and a back plate 491C.

[0073] In this device configured as described above, a sheet of paper 410 is fed onto and attracted to the conveyor belt 412, and the sheet of paper 410 is conveyed in the sub-scanning direction by the circular movement of the conveyor belt 412.

[0074] Therefore, by driving the liquid ejection head 404 in accordance with an image signal while moving the carriage 403 in the main scanning direction, liquid is ejected onto the stationary paper 410 to form an image.

[0075] As described above, this device is equipped with the liquid ejection head according to the present invention, and therefore can stably form high-quality images.

[0076] Next, another example of a liquid discharge unit according to the present invention will be described with reference to Fig. 15. Fig. 15 is an explanatory plan view of the main part of the unit.

[0077] This liquid ejection unit is composed of the components that make up the device for ejecting the liquid, including a housing portion consisting of side plates 491A, 491B and a back plate 491C, a main scanning movement mechanism 493, a carriage 403, and a liquid ejection head 404.

[0078] It is also possible to configure a liquid discharge unit in which at least one of the maintenance and recovery mechanism 420 and the supply mechanism 494 described above is further attached to, for example, the side plate 491B of this liquid discharge unit.

[0079] Next, still another example of a liquid discharge unit according to the present invention will be described with reference to Fig. 16. Fig. 16 is an explanatory front view of the unit.

[0080] This liquid ejection unit is composed of a liquid ejection head 404 and a tube 456 connected to a liquid supply section 444 of the liquid ejection head 404 .

[0081] 16 denotes an exterior cover 442. A liquid supply unit 444 may also include a head tank 441. Also, reference numeral 443 in FIG. 16 denotes a connector that electrically connects to an electrical circuit board.

[0082] In this application, a "liquid ejecting device" is a device that includes a liquid ejection head or a liquid ejection unit and ejects liquid by driving the liquid ejection head. Liquid ejecting devices include not only devices that can eject liquid onto objects to which the liquid can adhere, but also devices that eject liquid into air or liquid.

[0083] This "liquid ejecting device" can also include means for feeding, transporting, and discharging items onto which liquid can be attached, as well as pre-processing devices and post-processing devices.

[0084] For example, examples of "liquid ejecting devices" include image forming devices that eject ink to form images on paper, and three-dimensional modeling devices (three-dimensional modeling devices) that eject modeling liquid onto a powder layer formed from layers of powder in order to create a three-dimensional object (a three-dimensional model).

[0085] Furthermore, the term "liquid ejection device" is not limited to devices that use ejected liquid to visualize meaningful images such as letters and figures. For example, it also includes devices that form patterns that have no meaning in themselves, and devices that create three-dimensional images.

[0086] The term "something to which a liquid can adhere" means something to which a liquid can adhere at least temporarily, something to which the liquid adheres and sticks, something to which the liquid adheres and penetrates, etc. Specific examples include media such as paper, recording paper, film, and cloth, electronic circuit boards, electronic components such as piezoelectric elements, powder layers, organ models, and test cells, and unless otherwise specified, includes all things to which a liquid can adhere.

[0087] The material of the "substance to which a liquid can adhere" may be any material to which a liquid can adhere, even temporarily, such as paper, thread, fiber, fabric, leather, metal, plastic, glass, wood, ceramics, building materials such as wallpaper and flooring, and textiles for clothing.

[0088] "Liquid" also includes ink, processing liquid, DNA sample, resist, pattern material, binder, modeling liquid, or solutions and dispersions containing amino acids, proteins, calcium, and the like.

[0089] Furthermore, the "liquid ejection device" may be a device in which a liquid ejection head and an object onto which liquid can be attached move relatively, but is not limited to this. Specific examples include a serial type device in which a liquid ejection head moves, and a line type device in which a liquid ejection head does not move.

[0090] Other examples of "liquid ejecting devices" include a treatment liquid application device that ejects a treatment liquid onto paper to apply the treatment liquid to the surface of the paper for purposes such as modifying the surface of the paper, and an injection granulation device that ejects a composition liquid in which raw materials are dispersed through a nozzle to granulate fine particles of the raw materials.

[0091] A "liquid ejection unit" is a collection of components related to the ejection of liquid, integrating functional parts and mechanisms with a liquid ejection head. For example, a "liquid ejection unit" includes a combination of a liquid ejection head and at least one of the following components: a head tank, a carriage, a supply mechanism, a maintenance and recovery mechanism, and a main scanning movement mechanism.

[0092] Here, "integrated" includes, for example, a liquid ejection head and a functional part or mechanism that are fixed to each other by fastening, bonding, engaging, etc., or one that is held movably relative to the other. The liquid ejection head, functional part, or mechanism may also be configured to be detachable from each other.

[0093] For example, some liquid ejection units have a liquid ejection head and a head tank integrated together, such as liquid ejection unit 440 shown in Fig. 14. Other liquid ejection units have a liquid ejection head and a head tank integrated together by being connected to each other by a tube or the like. Here, a unit including a filter can be added between the head tank and the liquid ejection head of these liquid ejection units.

[0094] Furthermore, there is a liquid ejection unit in which the liquid ejection head and the carriage are integrated.

[0095] In some liquid ejection units, the liquid ejection head is movably held by a guide member that constitutes part of the scanning movement mechanism, and the liquid ejection head and the scanning movement mechanism are integrated together. In other liquid ejection units, as shown in Figure 15, the liquid ejection head, carriage, and main scanning movement mechanism are integrated together.

[0096] Furthermore, there is a liquid ejection unit in which a cap member, which is part of the maintenance and recovery mechanism, is fixed to a carriage on which a liquid ejection head is attached, thereby integrating the liquid ejection head, carriage, and maintenance and recovery mechanism.

[0097] Furthermore, as shown in FIG. 16, there is a liquid ejection unit in which a tube is connected to the liquid ejection head, and the liquid ejection head and a supply mechanism are integrated.

[0098] The main scanning movement mechanism includes the guide member alone, and the supply mechanism includes the tube alone and the loading unit alone.

[0099] Furthermore, the pressure generating means used in the "liquid ejection head" is not limited. For example, in addition to the piezoelectric actuator (which may use a laminated piezoelectric element) as described in the above embodiment, a thermal actuator using an electrothermal conversion element such as a heating resistor, or an electrostatic actuator consisting of a vibration plate and an opposing electrode may also be used.

[0100] In addition, in the present application, the terms image formation, recording, printing, copying, printing, modeling, etc. are all synonymous.

[0101] The above description is merely an example, and each of the following aspects provides unique effects. (Aspect 1) The liquid supply device includes an internal component such as a flow path component 3 and an external component such as an external cover 2 that covers the internal component. The internal component is joined to one side such as a bottom surface and the other side such as a ceiling surface that face each other via the internal component of the external component. The internal component includes a first member such as a head portion 3a and a second member such as a liquid supply portion 3b that is connected to the first member so as to be movable relative to the first member in a direction perpendicular to the joining surface of the internal component joined to the external component. Generally, the exterior part is box-shaped, and has an opening on its bottom surface through which a nozzle for ejecting liquid from the liquid ejection head is exposed, and an opening on its top surface through which a supply port to which a tube for supplying liquid from an external tank is connected passes. Conventionally, the nozzle side of the interior part is bonded to the bottom surface of the exterior part with an adhesive or the like, and the top surface opposite the nozzle side is bonded to the top surface of the exterior part with an adhesive or the like to prevent liquid from entering the exterior part through these openings. However, if the linear expansion coefficients of the internal and external components are different, there may be a difference in the dimensions of the two components after thermal expansion in a direction perpendicular to the joining surface where the internal component is joined to the external component, or there may be a difference in the dimensions of the two components in a direction perpendicular to the joining surface due to manufacturing errors. Such a difference in the dimensions of the two components in a direction perpendicular to the joining surface generates stress at the joining point in a direction perpendicular to the joining surface, and this stress may cause distortion in at least one of the external and internal components. In contrast, in this embodiment 1, the second member of the internal component is configured to be movable relative to the first member of the internal component in a direction perpendicular to the joining surface. As a result, even if a dimensional difference occurs between the internal component and the exterior component in the direction perpendicular to the joining surface, the second member moves relative to the first member, and the dimension of the internal component in the direction perpendicular to the joining surface can be made to match the dimension of the exterior component in the direction perpendicular to the joining surface. This makes it possible to prevent distortion from occurring in the exterior component and the interior component.

[0102] (Aspect 2) In the first embodiment, the second member such as the liquid supply portion 3b is connected to the first member such as the head portion 3a with a gap in the direction perpendicular to the joining surface. According to this, as described in the embodiment, when the dimension between the joining surfaces of an internal part such as the flow path part 3 is longer than the dimension between the joined surfaces of an external part such as the exterior cover 2, or when the linear expansion coefficient of the internal part is larger than the linear expansion coefficient of the exterior cover, the second member moves relative to the first member to narrow the gap and absorb the dimensional difference, thereby making it possible to prevent distortion from occurring in the external part or the internal part.

[0103] (Aspect 3) In the first or second embodiment, the coefficient of linear expansion of the exterior part such as the exterior cover 2 and the coefficient of linear expansion of the internal part such as the flow path part 3 are different from each other. As described in the embodiment, the difference in linear expansion coefficient between the exterior components such as the exterior cover 2 and the internal components such as the flow path components 3 causes a difference in thermal expansion between the exterior components and the internal components, but the second member moves relative to the first member to absorb this difference in thermal expansion, thereby preventing distortion of the exterior components and the internal components.

[0104] (Aspect 4) In any of aspects 1 to 3, a second internal component such as an electrical board 4 is provided which is fixed to a second member such as a lower liquid supply portion 3b1 and a member different from the second member such as an outer cover 2, and the internal component has a third member such as an upper liquid supply portion 3b2 which is movable relative to the second member in a direction perpendicular to the joining surface. As described in Modification 2, this allows the second member, such as the lower liquid supply unit 3b1, to move relative to the first member, such as the head unit 3a, and the third member, such as the upper liquid supply unit 3b2, in accordance with dimensional variations in the direction perpendicular to the joining surface due to thermal expansion of the second internal component, such as the electrical board 4, and dimensional errors in the direction perpendicular to the joining surface due to manufacturing errors. This makes it possible to prevent distortion of the second internal component. Furthermore, dimensional differences in the direction perpendicular to the joining surface between an exterior component, such as the exterior cover, and an interior component, such as the flow path component 3, can be absorbed by moving the third member and the first member relative to the second member, thereby preventing distortion of the exterior component and the interior component. Furthermore, by fixing the second internal component to a plurality of members, the position of the second internal component within the exterior component can be stabilized.

[0105] (Aspect 5) In any of aspects 1 to 3, the internal component such as the flow path component 3 has a third member such as an upper liquid supply portion 3b2 that is movable relative to a second member such as a lower liquid supply portion 3b1 in a direction perpendicular to the joining surface, and has a first removal prevention portion 37 that prevents the second member from removing from a first member such as the head portion 3a, and a second removal prevention portion 38 that prevents the second member from removing from a third member. As a result, as explained using Figures 11 and 12, when assembling the flow path parts to the exterior cover, it is possible to prevent the first member such as the head portion 3a from coming off the second member such as the lower liquid supply portion 3b1, and the third member such as the upper liquid supply portion 3b2 from coming off the second member.

[0106] (Aspect 6) In the fourth or fifth embodiment, the third member such as the upper liquid supply part 3b2 is connected to the second member with a gap in the direction perpendicular to the joining surface. This allows the second member, such as the lower liquid supply unit 3b1, to move in a direction perpendicular to the joining surface independently of the first member, such as the head unit 3a, and the third member, such as the upper liquid supply unit 3b2, as described in Modification 2. This allows the second member to move in accordance with the thermal expansion and dimensional error of the second internal part, such as the electrical board 4.

[0107] (Aspect 7) In any of aspects 1 to 6, the internal component is a flow path component 3 for flowing a liquid such as ink, and the liquid flows from one component to another via a connection point between components constituting the internal component, such as a connecting portion 10, and a sealing member such as an O-ring 33 for sealing the liquid is provided at the connection point. This can prevent liquid such as ink from leaking from connecting portions such as connecting parts.

[0108] (Aspect 8) In the seventh aspect, a guide portion 36 is provided to guide relative movement between members constituting the internal components such as the flow path component 3. As a result, as described in Modification 1, it is possible to suppress positional deviation in a direction perpendicular to the relative movement direction between the members that make up the internal parts, and it is possible to maintain the sealing properties of sealing members such as O-ring 33.

[0109] (Aspect 9) In any of the first to eighth embodiments, a sealing material such as the seal member 8 is provided at the joint between the internal part such as the flow path part 3 and the external part such as the external cover 2 . As a result, as described with reference to FIG. 7, it is possible to completely seal the gap at the joint between an internal part such as the flow path part 3 and an external part such as the external cover 2, thereby preventing liquids and the like from entering the external part through the joint.

[0110] (Aspect 10) The liquid ejection unit includes the liquid ejection head according to any one of aspects 1 to 9. This can suppress distortion of the liquid ejection head, and can suppress problems such as the liquid landing position being shifted from a specified position.

[0111] (Aspect 11) An apparatus for discharging liquid, such as an inkjet recording apparatus serving as an image forming apparatus, includes the liquid discharge head of any one of the first to ninth aspects or the liquid discharge unit of the tenth aspect. This allows the liquid to be ejected satisfactorily. [Explanation of symbols]

[0112] 1: Liquid ejection head 2: Exterior cover 2a: First cover member 2b: Second cover member 3: Flow path parts 3a: Head section 3b:Liquid supply section 3b1: Lower liquid supply section 3b2: Upper liquid supply section 4: Electrical board 6: Screws 7: Adhesive 8: Sealing material 10:Connection part 10a: First connection part 10b:Second connection part 21a: Opening 21b: Opening 21c: opening 31: Nozzle surface 31a: Nozzle 32: Supply port 33: O-ring 34: Connection recess 35: Connection insertion part 36: Guide section 37: First release prevention part 37a: First hook part 37b: First anti-detachment protrusion 38: Second release prevention part 38a: Second hook part 38b: Second anti-detachment protrusion 401: Guide member 403: Carriage 404: Liquid ejection head 405: Main scanning motor 420: Maintenance and recovery mechanism 440: Liquid dispensing unit 441: Head Tank 442: Exterior cover 444:Liquid supply section 450: Liquid cartridge 451: Cartridge holder 452: Liquid delivery unit 456: Tube 491A: Side panel 491B: Side plate 491C: Back plate 493: Main scanning movement mechanism 494: Supply mechanism [Prior art documents] [Patent documents]

[0113] [Patent Document 1] Japanese Patent Publication No. 2021-146573

Claims

1. Internal parts and an exterior part that covers the internal part, the internal component is joined to one surface and the other surface of the exterior component that face each other with the internal component interposed therebetween, the internal component includes a first member and a second member connected to the first member so as to be movable relative to the first member in a direction perpendicular to a joining surface of the internal component joined to the exterior component, a second internal component secured to the second member and to a member different from the second member; The liquid ejection head according to claim 1, wherein the internal component includes a third member connected to the second member so as to be movable relative to the second member in a direction perpendicular to the joining surface.

2. An internal component; an exterior part that covers the internal part, the internal component is joined to one surface and the other surface of the exterior component that face each other with the internal component interposed therebetween, the internal component includes a first member and a second member connected to the first member so as to be movable relative to the first member in a direction perpendicular to a joining surface of the internal component joined to the exterior component, the internal component has a third member connected to the second member so as to be movable relative to the second member in a direction perpendicular to the joining surface; A liquid ejection head characterized by having a first anti-detachment portion that prevents the second member from coming off the first member, and a second anti-detachment portion that prevents the second member from coming off the third member.

3. 3. The liquid ejection head according to claim 1, The liquid ejection head is characterized in that the third member is connected to the second member with a gap therebetween in a direction perpendicular to the joining surface.

4. The liquid ejection head according to any one of claims 1 to 3, The liquid ejection head is characterized in that the second member is connected to the first member with a gap therebetween in a direction perpendicular to the joining surface.

5. 5. The liquid ejection head according to claim 1, A liquid ejection head, wherein the exterior component and the interior component have different linear expansion coefficients.

6. The liquid ejection head according to any one of claims 1 to 5, The internal component is a flow path component for flowing a liquid, A liquid flows from one member to another member through a connection between the members constituting the internal component, A liquid ejection head characterized in that a seal member for sealing the liquid is provided at the connecting portion.

7. 7. The liquid ejection head according to claim 6, A liquid ejection head comprising a guide portion for guiding relative movement between members constituting the internal components.

8. 8. The liquid ejection head according to claim 1, A liquid ejection head characterized in that a sealant is provided at a joint between the internal part and the external part.

9. A liquid ejection unit comprising the liquid ejection head according to claim 1 .

10. 10. A liquid ejection device comprising: a liquid ejection head according to claim 1; or a liquid ejection unit according to claim 9.

Images