Liquid supply member and liquid ejection head

Abstract

To provide a liquid discharge head which can inhibit occurrence of leakage of air and liquid even in a state that a liquid chamber is compressed while suppressing meniscus vibration.SOLUTION: A liquid supply member includes a first member 10, a second member 3, and a damper member 19. The first member 10 is a member which forms a liquid chamber 13 for storing liquid to be supplied to a discharge port which discharges the liquid, and the damper member 19 is a flexible member which forms the liquid chamber 13 with the first member 10. The second member 3 is a member which forms an atmosphere communication chamber 31 communicating with atmospheric air at a position which is located between the second member 3 and the damper member 19 and faces the liquid chamber 13 through the damper member 19. A portion located at a center part of the second member 3 is formed with a protruding part 35 protruding to the damper member 19 relative to a connection surface between the damper member 19 and the second member 3.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a liquid supply member and a liquid ejection head.

Background Art

[0002] A liquid ejection device such as an inkjet printer includes a liquid ejection head that ejects a liquid such as ink. When the liquid ejection head ejects a liquid at a high rate with respect to the total number of ejection ports, such as ejecting the liquid from all the ejection ports, the position of the meniscus at the ejection port vibrates. When the next ejection operation is performed with the meniscus in a state where it has protruded forward or retreated backward due to such meniscus vibration, small droplets scatter in the former case, and the ejection speed and ejection amount become small in the latter case. Therefore, in either case, there is a risk that the ejection accuracy of the liquid will decrease.

[0003] Therefore, Patent Document 1 discloses a liquid ejection head in which a flexible damper portion is provided in a part of the liquid chamber and the meniscus vibration at the ejection port can be suppressed. In Patent Document 1, in order to improve the effect of suppressing the meniscus vibration, a configuration is adopted in which a region on the side opposite to the liquid chamber side of the damper portion communicates with the atmosphere.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] As described above, in order to improve the damping effect of the meniscus vibration, when the region on the side opposite to the liquid chamber side of the damper portion is communicated with the atmosphere, even if the damper portion is deformed, the pressure in the region remains constant at atmospheric pressure. Therefore, the displacement amount of the damper portion becomes larger as compared with the case where the region is not communicated with the atmosphere. Thus, for example, when the liquid chamber is pressurized for some reason such as cleaning of the liquid ejection head, the damper portion is largely displaced in the direction opposite to the liquid chamber side, and air or liquid may leak from the connection portion between the damper portion and the flow path member connected to the damper portion.

[0006] In view of the above problems, an object of the present invention is to provide a liquid ejection head that can suppress meniscus vibration and suppress leakage of air or liquid even when the liquid chamber is in a pressurized state.

Means for Solving the Problems

[0007] In order to solve the above problems, the present invention Liquid supply member includes a first member, a second member, and a damper member sandwiched between the first member and the second member. The first member is a member that forms a liquid chamber for storing liquid to be supplied to a discharge port for discharging liquid. The damper member is a flexible member that forms the liquid chamber together with the first member. The second member is located between the damper member and at a position facing the liquid chamber via the damper member, Via the air communication passage and is a member that forms an atmosphere communication chamber communicated with the atmosphere. At a position facing the end of the damper member, it has an outer edge portion that protrudes toward the damper member from the connection surface between the damper member and the second member, and the opening on the air communication chamber side of the air communication passage is formed in a region surrounded by the outer edge portion. A protruding portion that protrudes toward the damper member more than the connection surface between the damper member and the second member is formed at a portion of the surface of the second member facing the atmosphere communication chamber and located at the central portion of the damper member.

Effects of the Invention

[0008] According to the liquid ejection head of the present invention, it is possible to suppress meniscus vibration and suppress leakage of air or liquid even when the liquid chamber is in a pressurized state.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

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MODE FOR CARRYING OUT THE INVENTION

[0010] Hereinafter, embodiments of the present invention will be described in detail.

[0011] (First Embodiment) (Liquid Ejection Head) The liquid ejection head will be described with reference to FIGS. 1, 2, and 10. FIG. 1(a) is a perspective view showing the liquid ejection head 100. FIG. 1(b) is an exploded perspective view of the liquid ejection head 100. The liquid ejection head 100 mainly includes a support member (first member) 10, an element substrate 2, a housing 3a, a flow path member (second member) 3 including a flow path plate 3b, and a joint member 9. The flow path member 3, the joint member 9, and the support member 10 are mainly connected (joined) by screws 23.

[0012] The housing 3a is mainly a member for mounting an ink tank that stores liquid (ink). The flow path plate 3b has a flow path 1 for supplying the liquid from the ink tank to the element substrate 2. The joint member 9 is a member for connecting the flow path plate 3b and the support member 10, and prevents the liquid from leaking from the gap between the flow path plate 3b and the support member 10. The joint member 9 is formed of a flexible member, for example, a rubber member, etc., and has a damper member 19 for suppressing fluctuations in the pressure in the liquid chamber 13 (FIG. 2). The liquid chamber 13 is composed of an ink storage chamber 7 that stores ink and a buffer chamber 4 that can hold bubbles generated in the ink storage chamber 7. FIG. 10 shows a schematic top view around the damper member 19 of the joint member 9 shown in FIG. 1(b). The damper member 19 has a shape with a long side and a short side, and two damper members 19 are provided in one liquid ejection head 100. And between the two damper members 19, there is an inlet 15 that communicates with the through hole 14 (FIG. 2). The support member 10 is a member for supporting the element substrate 2. The element substrate 2 includes a pressure generating element that generates pressure for ejecting liquid and an ejection port for ejecting liquid.

[0013] FIG. 2 is a schematic view showing a cross-sectional view of the liquid ejection head 100 shown in FIG. 1. In the support member 10, a liquid chamber 13 for storing the liquid supplied to the element substrate 2 is formed. The liquid passes through the through hole 14 of the flow path plate 3b and is supplied to the liquid chamber 13 formed in the support member. Then, the liquid supplied to the liquid chamber 13 is supplied to the ejection port of the element substrate 2.

[0014] The liquid chamber 13 has a shape such that the distance between the surface 7b and the surface 7a of the liquid chamber decreases toward the end 72 of the surface 7a on the liquid chamber side of the element substrate 2. A buffer chamber 4, which is a cavity formed by the damper member 19 of the joint member 9, is provided on the surface 7b. The damper member 19 is a flexible member and is formed of, for example, rubber. Since the damper member 19 is formed facing the liquid chamber 13, even if the pressure in the liquid chamber fluctuates, the damper member 19 deforms in response to this pressure fluctuation, so that the pressure fluctuation in the liquid chamber can be suppressed.

[0015] An atmosphere communication chamber 31 is formed on the side of the damper member 19 opposite to the buffer chamber 4, and the atmosphere communication chamber 31 communicates with the atmosphere through an atmosphere communication passage 32 formed in the flow path plate 3b. Since the side of the damper member 19 opposite to the buffer chamber 4 communicates with the atmosphere, the atmosphere communication chamber 31 maintains atmospheric pressure regardless of the amount of deformation of the damper member 19, so that the amount of deformation of the damper member 19 can be increased. Thereby, the pressure vibration in the liquid chamber can be more suppressed.

[0016] (Protrusion) The protrusion will be described with reference to FIGS. 3 to 7. FIG. 3 is a schematic view showing a cross-sectional view of a conventional liquid ejection head, and corresponds to the cross-sectional view of the liquid ejection head of the present embodiment shown in FIG. 2. FIG. 4 is a schematic view showing the surface 5 on the side facing the joint member 9 of the conventional flow path plate 3b shown in FIG. 3. FIG. 5(a) is a schematic view of the A-A cross section shown in FIG. 3. FIG. 5(b) is a schematic view showing the state of the damper member 19 when the inside of the liquid chamber 13 is pressurized from the state shown in FIG. 5(a). FIG. 6 is a schematic view showing the flow path plate 3b of the present embodiment shown in FIG. 2, and is a view corresponding to FIG. 4. FIG. 7(a) is a schematic view of the B-B cross section shown in FIG. 2. FIG. 7(b) is a schematic view showing the state of the damper member 19 when the inside of the liquid chamber 13 is pressurized from the state shown in FIG. 7(a).

[0017] As shown in FIG. 4, on the surface 5 of the conventional flow path plate 3b, an outer edge member 34 is formed at a position facing the end of the damper member 19. This outer edge member 34 is for fixing the flow path plate 3b and the damper member 19 at appropriate positions. FIG. 5(b) shows a state where the inside of the liquid chamber 13 is pressurized. On the contrary, when the inside of the liquid chamber 13 is in a depressurized state, the damper member 19 deforms toward the liquid chamber 13 side, and the end 8a of the damper member 19 is pulled toward the central portion. At this time, if the end 8a of the damper member 19 is excessively deformed toward the central portion, a gap is likely to occur between the lip portion 191a at the end of the damper member 19 and the flow path plate 3b. However, since the end face 8b of the joint member 9 is in contact with the outer edge member 34, the occurrence of leakage at the lip portion 191a of the damper member 19 can be suppressed. Here, the end 8a of the damper member 19 refers to the region from the end face 8b (outer edge) of the joint member 9 to a length of d / 3 (see FIG. 10) when the shortest distance from the center of gravity of the damper member 19 to the outer edge of the damper member 19 is d. Also, the damper member 19 refers to the region that deforms in response to pressure fluctuations in the liquid chamber 13. That is, in the case shown in FIG. 5(a), the thin plate-like portion between the two end faces 8b is the damper member 19.

[0018] On the other hand, as shown in FIG. 5(b), when the inside of the liquid chamber 13 is pressurized, the damper member 19 deforms toward the atmosphere communication chamber 31. Then, the end of the damper member 19 is pulled toward the central portion. At this time, if the amount of deformation of the damper member 19 toward the atmosphere communication chamber 31 side exceeds a certain amount, the lip portion 191b, which is the connection portion between the damper member 19 and the support member 10, of the damper member 19 will lift up, and leakage of liquid or air will occur.

[0019] Therefore, among the surfaces of the flow path member (second member) 3 facing the atmosphere communication chamber 31, a protruding portion 35 that protrudes toward the damper member 19 is formed at a portion located at the center of the damper member 19, which is more protruding toward the damper member 19 than the connection surface 16 (FIG. 7) between the damper member 19 and the flow path member 3. The reason for forming the protruding portion 35 at a position of the flow path member (second member) 3 facing the center of the damper member 19 is that the deformation amount of the central portion of the damper member 19 is large. By forming the protruding portion 35 at a position facing the central portion with a large deformation amount, it is possible to suppress the excessive deformation of the damper member 19 and suppress the occurrence of leakage at the lip portion 191b. Specifically, the protruding portion 35 in the present embodiment has a column shape as shown in FIGS. 2, 6, and 7, and is formed over the entire region excluding the opening 33 (hereinafter simply referred to as the opening 33) on the atmosphere communication chamber side of the atmosphere communication path 32 in the region surrounded by the outer edge member 34. The central portion of the damper member 19 refers to a region surrounded by a circle with a radius of d / 2 centered on the center of gravity of the damper member 19 when the shortest distance from the center of gravity of the damper member 19 to the outer edge of the damper member 19 is d (see FIG. 10) when viewed from the protruding direction of the protruding portion 35. Further, the fact that the protruding portion 35 is formed over the entire region excluding the opening 33 of the atmosphere communication path 32 in the region surrounded by the outer edge member 34 means a state in which the protruding portion 35 occupies 90% or more of the volume surrounded by the outer edge member 34.

[0020] The protruding portion 35 is formed by integral molding with the flow path plate 3b. However, the flow path plate 3b and the protruding portion 35 may be separate members, and the protruding portion 35 may be assembled into the hollow portion 36 of the outer edge member 34 by press fitting, welding, or the like.

[0021] In order to suppress the occurrence of leakage during pressurization of the liquid chamber, if the distance between the surface 12 of the cover plate 3b facing the damper member 19 and the damper member 19 is shortened, the large deformation of the damper member 19 can be suppressed, and the occurrence of leakage can also be suppressed. However, in order to fit and connect the flow path plate 3b and the damper member 19, the end portion 8 of the damper member 19 requires a certain thickness, and the outer edge member 34 needs to be provided on the flow path plate 3b. Therefore, there is a limit to shortening the distance between the surface 12 of the cover plate 3b and the damper member 19. Therefore, in order to suppress the occurrence of leakage during pressurization of the liquid chamber 13, the above-described protruding portion 35 is effective.

[0022] As shown in FIG. 7, the protruding portion 35 is not in contact with the damper member 19. This is to prevent the deformation of the damper member 19 at the contact portion from being suppressed and the function as a damper from being reduced if the protruding portion 35 comes into contact with the damper member 19. Also, if the protruding portion 35 protrudes only slightly toward the damper member 19 side, the effect of suppressing the excessive deformation of the damper member 19 is reduced. From the above, it is preferable that the tip of the protruding portion 35 is set to be not less than D / 5 and not more than 4D / 5 from the surface 17 when the distance between the surface 17 on the flow path member 3 side (second member side) of the joint member 9 and the damper member 19 is D.

[0023] In the present embodiment, the outer edge member 34 has been described with reference to the drawings in which it is illustrated. However, in the present embodiment, the outer edge member 34 may not be formed on the flow path plate 3b. Even if the outer edge member 34 is not formed, the formation of the protruding portion 35 can suppress the excessive deformation of the damper member 19 and can suppress the occurrence of leakage of air or liquid even when the inside of the liquid chamber is pressurized.

[0024] (Second Embodiment) The second embodiment will be described with reference to FIGS. 8 and 9. Note that the same reference numerals are given to the same parts as those in the first embodiment, and the description thereof will be omitted. FIG. 8(a) is a schematic view showing the protruding portion 35 in the present embodiment, and is a view corresponding to FIG. 4. FIG. 8(b) is a drawing corresponding to FIG. 2 in the case where the protruding portion 35 shown in FIG. 8(a) is formed. FIG. 9 is a schematic view showing a modification of the present embodiment. The present embodiment is characterized in that the shape of the protruding portion 35 is different from that of the first embodiment. The protruding portion 35 formed on the flow path plate 3b shown in FIG. 8 has a shape that connects to the two long sides of the outer edge member 34.

[0025] In the first embodiment, the protruding portion 35 is formed over the entire area of the hollow portion 36 of the outer edge member 34 excluding the atmosphere communication path 32. Therefore, the opening 33 of the atmosphere communication path 32 becomes the upper surface 11 of the protruding portion 35 (the surface facing the damper member 19 of the protruding portion 35). In this case, as shown in FIG. 7(b), when the damper member 19 is deformed toward the atmosphere communication chamber 31, the opening 33 of the atmosphere communication path 32 may be blocked by the deformed damper member 19. Therefore, in the present embodiment, the position where the protruding portion 35 is provided is limited so that the opening 33 on the atmosphere communication path side is formed on the surface 5 of the flow path plate 3b. Thereby, even when the damper member 19 is deformed toward the atmosphere communication chamber 31, it is possible to suppress the opening 33 of the atmosphere communication path 32 from being blocked.

[0026] Specifically, in FIG. 8, the protruding portion 35 is formed at a position facing the central portion of the damper member 19 where the displacement of the damper member 19 is large, and is not formed in the entire area of the hollow portion 36. The protruding portion 35 is formed so as to divide the hollow portion 36 surrounded by the outer edge member 34 into two parts. Further, since the formation region of the protruding portion 35 of the present embodiment is smaller than the protruding portion 35 shown in FIG. 7, even when a flow path having a complicated shape is formed on the back surface of the surface 5 of the flow path plate 3b, the moldability can be improved.

[0027] Further, in the present embodiment, as shown in FIG. 9, a protruding portion 35 having a shape that bridges the four sides of the outer edge member 34 may be formed. That is, the protruding portion 35 may be formed so that the hollow portion 36 is divided into four parts. At this time, the opening 33 of the air communication path 32 is preferably formed over a plurality of locations among the hollow portions 36 divided by the protruding portion 35. By forming the opening 33 of the air communication path 32 over a plurality of locations, it is possible to further suppress the opening 33 of the air communication path 32 from being blocked due to the deformation of the damper member 19. The opening 33 of the air communication path 32a shown in the upper part of FIG. 9 is formed across two regions among the four divided hollow portions 36. Also, the opening 33 of the air communication path 32a shown in the lower part of FIG. 9 is formed across the four regions of the divided hollow portion 36.

[0028] In FIGS. 8 and 9, an example is illustrated in which one opening 33 is formed at a position spanning a plurality of regions divided by the protruding portion 35, but the present embodiment is not limited to this. That is, even if the opening 33 does not span a plurality of regions, for example, four openings 33 may be formed in each of the four divided regions. The same effect can be obtained.

[0029] In the present embodiment shown in FIGS. 8 and 9, an example is illustrated in which the protruding portion 35 is formed in a circle centered on the center of gravity of the damper member 19 with a radius of d / 2, but it is more preferable that the protruding portion 35 is formed within a circle centered on the center of gravity of the damper member 19 with a radius of d / 3. Further, it is more preferable that the protruding portion 35 is formed within a circle centered on the center of gravity of the damper member 19 with a radius of d / 4. Since the damper member 19 of the shape shown in each embodiment deforms around the center of gravity, the amount of deformation at the center of gravity is the largest. Therefore, it is more preferable that the protruding portion 35 is formed within a circle centered on the center of gravity of the damper member 19 with a radius of d / 3 or within a circle with a radius of d / 4 rather than within a circle centered on the center of gravity of the damper member 19 with a radius of d / 2.

[0030] (Third Embodiment) The third embodiment will be described with reference to FIGS. 11, 12, and 13. Note that the same reference numerals are given to the same parts as those in the first embodiment, and the description thereof will be omitted. FIG. 11 is an exploded perspective view of the liquid ejection head 200, which corresponds to FIG. 1. FIG. 12 is a schematic view of the joint member 90. FIG. 13 is a schematic view showing a modification of the present embodiment, which corresponds to FIG. 7.

[0031] This embodiment is different from the first and second embodiments in that the shape of the flow path member 3c and the damper protrusion 92 is provided on the damper member 19 of the joint member 90.

[0032] The configuration and effects of this embodiment will be described with reference to FIGS. 12 and 13. In this embodiment, as shown in FIG. 12(a), a damper protrusion 92 that divides the damper member 19 into two parts is formed at the center of the damper member 19 of the joint member 90. Further, in this embodiment, as shown in FIG. 12(b), the damper protrusion 92 may be formed so as to divide the damper member 19 into four parts. This joint member 90 is sandwiched between the flow path member 3c and the first member 10 as shown in FIG. 13(a). When the inside of the liquid chamber 13 is pressurized at this time, the damper member 19 deforms toward the atmosphere communication chamber 31. However, in this embodiment, the damper protrusion 92 is provided on the damper member 19, and the deformation is suppressed by contacting the flow path member 3c during deformation. Thereby, leakage at the lip portion 191b can be suppressed.

[0033] As described above, the liquid ejection head 100 has been described as an example for each embodiment, but the present invention is not limited thereto. That is, the present invention can be preferably applied to a liquid supply member (for example, an ink tank or a flow path member separate from the element substrate) for supplying liquid to the ejection port.

Description of Reference Numerals

[0034] 3 Second member 13 Liquid chamber 10 First member 19 Damper member 31 Atmosphere communication chamber 35 protrusion

Claims

1. It has a first member, a second member, and a damper member sandwiched between the first member and the second member, The first member is a member that forms a liquid chamber for storing liquid to be supplied to a discharge port for discharging the liquid, The damper member is a flexible member that forms the liquid chamber together with the first member, The second member is A member that forms an atmosphere communication chamber that communicates with the atmosphere via an atmosphere communication passage at a position between the damper member and facing the liquid chamber via the damper member, It has an outer edge portion that protrudes toward the damper member from the connection surface between the damper member and the second member at a position facing the end portion of the damper member, The opening on the atmosphere communication chamber side of the atmosphere communication passage is formed in a region surrounded by the outer edge portion, A liquid supply member, wherein a protruding portion that protrudes toward the damper member from the connection surface between the damper member and the second member is formed at a portion of the surface of the second member facing the atmosphere communication chamber and located at the central portion of the damper member.

2. The liquid supply member according to claim 1, wherein the protruding portion is formed over the entire region excluding the atmosphere communication passage in the region surrounded by the outer edge portion.

3. The liquid supply member according to claim 1, wherein the protruding portion is formed so as to divide the region surrounded by the outer edge portion into a plurality of regions.

4. The liquid supply member according to claim 3, wherein the protruding portion is formed so as to divide the region surrounded by the outer edge portion into two parts.

5. The liquid supply member according to claim 3, wherein the protruding portion is formed so as to divide the region surrounded by the outer edge portion into four parts.

6. The opening of the air communication passage is an area surrounded by the outer edge portion, and is formed in a plurality of areas divided by the protruding portion, according to any one of claims 3 to 5 of the liquid supply member.

7. The opening of the air communication passage is an area surrounded by the outer edge portion, and is formed in two areas divided by the protruding portion, according to the liquid supply member of claim 6.

8. The opening of the air communication passage is an area surrounded by the outer edge portion, and is formed in four areas divided by the protruding portion, according to the liquid supply member of claim 6.

9. Comprising the damper member which is a region that deforms in response to pressure fluctuations in the liquid chamber, having a joint member connecting the first member and the second member, When the distance between the surface on the second member side of the joint member and the damper member is D, the tip of the protruding portion is D / 5 or more and 4D / 5 or less from the surface, according to any one of claims 1 to 8 of the liquid supply member.

10. Having a first member, a second member, and a damper member sandwiched between the first member and the second member, The first member is a member that forms a liquid chamber for storing liquid to be supplied to a discharge port for discharging the liquid. The damper member is a flexible member that forms the liquid chamber together with the first member. The second member is A member that forms an air communication chamber communicating with the atmosphere through an air communication passage at a position between the damper member and facing the liquid chamber through the damper member. At a position facing the end of the damper member, having an outer edge portion protruding toward the damper member from the connection surface between the damper member and the second member. The opening on the air communication chamber side of the air communication passage is formed in a region surrounded by the outer edge portion. The liquid supply member is characterized in that a damper protrusion protruding toward the second member is formed at a portion located at the center of the damper member on the surface of the damper member facing the atmosphere communication chamber.

11. The liquid supply member according to claim 10, wherein the damper protrusion is formed so as to divide a region surrounded by the outer periphery of the damper member into a plurality of regions.

12. The liquid supply member according to claim 11, wherein the damper protrusion is formed so as to divide a region surrounded by the outer periphery of the damper member into two parts.

13. The liquid supply member according to claim 11, wherein the damper protrusion is formed so as to divide a region surrounded by the outer periphery of the damper member into four parts.

14. The liquid supply member according to any one of claims 1 to 13, wherein the first member is a support member that supports an element substrate having a discharge port.

15. The liquid chamber of the first member has a shape such that the distance between the side surface of the liquid chamber and the surface of the element substrate on the liquid chamber side decreases from the damper member side toward the surface side opposite to the damper member. The liquid supply member according to claim 14.

16. The liquid supply member according to any one of claims 1 to 15, wherein the second member is a flow path member having a flow path for supplying liquid to the liquid chamber.

17. The liquid supply member according to any one of claims 1 to 16, wherein the damper member includes a rubber member.

18. The liquid supply member according to any one of claims 1 to 17, and An element substrate having a pressure generating element for generating a pressure for discharging liquid, and A liquid discharge head characterized by comprising.

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