LIQUID EJECTION HEAD AND METHOD FOR INSPECTING LEAKAGE AT LIQUID SUPPLY PORT OF LIQUID EJECTION HEAD

Abstract

To enable all liquid supply ports to be tested for leaks in one test even if the spacing between the liquid supply ports is small.SOLUTION: A liquid ejection head 17 includes an ejection-opening forming member 13 and a substrate 14. The substrate 14 has a plurality of liquid supply ports 1-5 arranged in an array direction. Grooves 1c, 3c, 5c in communication with ends 1d-5d of the liquid supply ports 1-5 are formed in a region 20. The grooves 1c, 3c, 5c extend from at least one end of the liquid supply ports which are located at both ends of the plurality of liquid supply opening 1-5. The groove 1c, 3c, 5c extends from at least to a position where the groove overlaps with one liquid supply opening adjacent to the liquid supply opening in which the groove is formed.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a liquid ejection head and a method for inspecting a liquid supply port of the liquid ejection head for leaks. [Background technology]

[0002] There is a recording device equipped with a liquid ejection substrate capable of ejecting multiple types of liquid (multiple colors of ink) from ejection ports. In such a liquid ejection substrate, a liquid supply port for supplying liquid to the ejection ports is formed for each color. When a liquid supply port is formed for each color, if a leak occurs in the liquid supply port, problems may occur such as ink flowing into the liquid supply port of another color and becoming mixed with the other colors, or ink flowing out of the liquid ejection substrate from the leak point.

[0003] Therefore, Patent Document 1 discloses a method of providing an inspection groove between two adjacent liquid supply ports to check for leaks at the liquid supply ports. A constant pressure is applied to the inspection groove and pressure fluctuations within the groove are measured to check for leaks between the two liquid supply ports. In addition, because the inspection grooves are formed between all of the liquid supply ports, it is possible to check for leaks at all of the liquid supply ports in a single inspection. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2008-74035 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, the method described in Patent Document 1 requires forming a groove for inspection between the liquid supply ports, and when the space between the liquid supply ports is narrowed, it is difficult to form the groove due to space limitations, making it difficult to use the configuration described in Patent Document 1 for a small liquid ejection substrate.

[0006] Therefore, a method for inspecting for leaks without providing an inspection groove so that inspection can be performed even when the space between liquid supply ports is narrowed will be described with reference to Figs. 3 and 4. Fig. 3(a) is a perspective view showing a liquid ejection head 17. As shown in Fig. 3(a), the liquid ejection head 17 has a liquid ejection substrate 16 made of an ejection port forming member 13 having an ejection port 18 for ejecting liquid and a substrate 14, and a liquid supply member 15. The substrate 14 supports the ejection port forming member 13. The liquid supply member 15 is a member that supplies liquid to the liquid supply ports 1 to 5 from inlets 1a to 5a formed in the substrate 14.

[0007] Fig. 3(b) is a perspective view of the liquid ejection substrate 16 shown in Fig. 3(a) seen from the ejection port side. Fig. 3(c) is a schematic view of the liquid ejection substrate 16 in the A-A' cross section shown in Fig. 3(b). As shown in Fig. 3(c), the liquid supply ports 1-5 communicate with the inlets 1a-5a and the ejection ports 1b-5b. The liquid supply ports 1-5 are formed for each color of liquid to be ejected.

[0008] FIG. 4 is a schematic diagram showing a method for inspecting the liquid supply ports 1 to 5 shown in FIG. 3 for leaks. FIG. 4(a) is a schematic diagram showing a leak inspection device 11 connected to a liquid discharge substrate 16. FIG. 4(b) is a top view of FIG. 4(a). FIG. 4(c) is a top view showing leak points 100 to 102. After the liquid discharge head 17 is completed, the discharge ports 1b to 5b are first blocked with a contact member 12. Next, the leak inspection device 11 is connected to the inlets 1a, 3a, and 5a of the liquid supply ports 1, 3, and 5 to be inspected for leaks, and compressed air (for example, 90 kPa) is supplied to the liquid supply ports 1, 3, and 5. At this time, the liquid supply ports 2 and 4 that are not inspected at the same time are left open to the atmosphere. The pressure fluctuations (for example, pressure fluctuations of 3.0 Pa or more) in the liquid supply ports 1, 3, and 5 after the compressed air is supplied are measured, and the presence or absence of leaks in the liquid supply ports 1, 3, and 5 to be inspected is inspected (first leak inspection). If a leak occurs at the locations (100-102) shown in FIG. 4(c), liquid supply port 1 communicates with the outside through leak 100, so the compressed air in liquid supply port 1 escapes to the outside (atmosphere), and the pressure drops. Also, liquid supply port 3 communicates with liquid supply port 2, which is open to the atmosphere, through leak 101, so the compressed air in liquid supply port 3 escapes to the atmosphere, and the pressure drops. Due to such pressure fluctuations, the presence of leaks 100 and 101 can be detected in this first leak test. However, since leak test device 11 is not connected to liquid supply ports 2 and 4, the presence of a leak such as leak 102 occurring only in liquid supply port 4 cannot be detected.

[0009] Therefore, after the leak inspection of the liquid supply ports 1, 3, and 5 is completed, the leak inspection of the liquid supply ports 2 and 4 is performed next. The connection destination of the leak inspection device 11 is switched to the liquid supply ports 2a and 4a, and compressed air is supplied to the liquid supply ports 2 and 4. At this time, the liquid supply ports 1, 3, and 5 that are not inspected at the same time are left open to the atmosphere. Then, the pressure fluctuation in the liquid supply ports 2 and 4 after the compressed air is supplied is measured to check for the presence or absence of a leak (second leak inspection). This second leak inspection makes it possible to detect the presence of a leak 102 that could not be detected in the first leak inspection. In this manner, all the liquid supply ports 1 to 5 are inspected for leaks.

[0010] If the leak inspection device 11 is connected to all the liquid supply ports 1 to 5 at once, it is not possible to detect leaks such as the leak 101 that exist only between the liquid supply ports. This is because, since both liquid supply ports 2 and 3 are connected to the leak inspection device 11, there is nowhere for the compressed air to escape, and no fluctuation occurs in the pressure inside the liquid supply ports 2 and 3. Therefore, with the above-mentioned method, the inspection can only be performed by alternating between the liquid supply port to be inspected and the liquid supply port that is open to the atmosphere, and the leak inspection must be performed twice (multiple times). In other words, it is not possible to inspect all the liquid supply ports for leaks in one inspection. This makes the inspection complicated.

[0011] Therefore, in consideration of the above-mentioned problems, the present invention aims to provide a liquid ejection substrate and a leak inspection method that can perform leak inspection for all liquid supply ports in a single inspection, even when the space between the liquid supply ports is narrowed. [Means for solving the problem]

[0012] In order to solve the above problems, the present invention provides a liquid ejection head comprising an ejection port forming member which forms an ejection port for ejecting liquid, and a substrate supporting the ejection port forming member, wherein the substrate has an array of multiple liquid supply ports formed thereon for supplying liquid to the ejection port, wherein a groove communicating with the end of the liquid supply port is formed in an area between an end of the liquid supply port in the extension direction of the liquid supply port and an outer edge of the substrate intersecting the extension direction, the groove extending from the end of at least one of the liquid supply ports located at both ends among the multiple liquid supply ports, and the groove extending at least to a position where it overlaps in the extension direction with another liquid supply port adjacent to the liquid supply port in which the groove is formed. Effect of the Invention

[0013] According to the present invention, it is possible to provide a liquid ejection substrate and a leak inspection method that are capable of inspecting all liquid supply ports for leaks in a single inspection even when the space between the liquid supply ports is narrowed. [Brief description of the drawings]

[0014] [Figure 1] FIG. 2 is a schematic diagram showing a liquid ejection substrate according to the first embodiment. [Diagram 2] FIG. 11 is a top view showing a liquid ejection substrate according to a second embodiment. [Diagram 3] FIG. 4 is a schematic diagram showing a liquid ejection substrate of a comparative example. [Figure 4] FIG. 13 is a schematic diagram showing a leak inspection according to a comparative example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] (First embodiment) Fig. 1(a) is a top view showing a state in which a leak inspection device 11 is connected to a liquid ejection substrate 16 of this embodiment, that is, a view seen from a direction (z direction) perpendicular to the main surface of the substrate 14. Fig. 1(b) is a schematic diagram showing grooves 1c, 3c, and 5c superimposed on the BB' cross section shown in Fig. 1(a). Fig. 1(c) is a schematic diagram showing leaks 100-102 on the top view of Fig. 1(a). Explanations of parts that overlap with the description of the comparative example described using Fig. 4 will be omitted.

[0016] The liquid supply ports 1 to 5 are arranged in the arrangement direction (the direction perpendicular to the x direction and the z direction). In this embodiment, grooves 1c, 3c, and 5c are formed in the substrate 14 so as to communicate with the liquid supply ports 1, 3, and 5 to which compressed air is supplied by the leak inspection device 11. The grooves 1c, 3c, and 5c are formed in a region 20 between the ends 1d, 3d, and 5d of the liquid supply ports in the extension direction (x direction) of the liquid supply ports and the outer edge 18 of the substrate 14 that intersects with the x direction. The grooves 1c, 3c, and 5c extend at least to a position where there is an overlapping portion in the arrangement direction of the liquid supply ports 1 to 5 with other liquid supply ports adjacent to the liquid supply port in which the groove is formed. That is, for example, when attention is paid to the groove 1c, the groove 1c extends to a position where there is an overlapping portion in the arrangement direction with the liquid supply port 2, which is the liquid supply port adjacent to the liquid supply port 1 in which the groove 1c is formed.

[0017] The leak inspection device 11 is connected to the liquid supply ports 1, 3, and 5 via grooves 1c, 3c, and 5c. The liquid supply ports 2 and 4 are open to the atmosphere. The presence or absence of a leak is inspected by supplying compressed air from the leak inspection device 11 to the liquid supply ports 1, 3, and 5 and measuring the pressure fluctuations in the liquid supply ports. When the leaks 101-102 occur at the positions shown in FIG. 1(c), the presence of the leak 102 cannot be detected in the first leak inspection in the method of the comparative example in FIG. 4 described above. Therefore, a second leak inspection was performed.

[0018] In this embodiment, by forming grooves 1c, 3c, and 5c, grooves 3c and 5c are connected to leak 102. As a result, the compressed air in liquid supply ports 3 and 5 escapes to the outside through leak 102, so that pressure fluctuations caused by leak 102 can also be detected in a single leak test. Therefore, in the present invention, leaks occurring in all liquid supply ports can be detected in a single leak test. Furthermore, since there is no need to form inspection grooves between liquid supply ports as in Patent Document 1, leak tests can be performed appropriately even when the space between liquid supply ports is narrowed.

[0019] In order to inspect all the liquid supply ports in one inspection, in addition to the grooves 1c, 3c, and 5c, it is necessary to connect the leak inspection device 11 to the liquid supply ports 1 and 5 located at both ends of the multiple liquid supply ports. If the leak inspection device 11 is not connected to the liquid supply ports 1 and 5 at both ends, it will be impossible to detect a leak such as the leak 100. For the other liquid supply ports, it is necessary to alternate between the liquid supply ports to which the leak inspection device 11 is connected and the liquid supply ports that are open to the atmosphere. If both the liquid supply ports 2 and 3 are connected to the leak inspection device 11 or open to the atmosphere, it will be impossible to detect a leak such as the leak 101.

[0020] The steps of the leak inspection described above can be summarized as follows. First, a step of preparing substrate 14 having grooves formed therein is performed. Next, a step of supplying compressed air into the liquid supply ports located at both ends of the multiple liquid supply ports is performed. In addition, a step of leaving the liquid supply ports to which compressed air is not supplied open to the atmosphere is performed. Finally, a step of measuring the pressure fluctuations in the liquid supply ports to which compressed air is supplied is performed.

[0021] As for the preferred form of the grooves 1c, 3c, and 5c, it is more preferable to make the depth of the grooves 1c, 3c, and 5c shallower than the depth of the liquid supply ports 1 to 5 from the viewpoint of ensuring the strength of the substrate. Specifically, it is preferable to make the depth of the grooves 1c, 3c, and 5c one tenth or less of the depth of the liquid supply port. Here, the depth refers to the length in the direction (x direction) perpendicular to the main surface 19 of the substrate 14. Similarly, from the viewpoint of the strength of the substrate, it is more preferable to make the width of the grooves 1c, 3c, and 5c smaller than the width of the liquid supply ports 1 to 5. Specifically, it is preferable to make the width of the grooves one half or less of the width of the liquid supply port. Here, the width of the grooves 1c, 3c, and 5c refers to the length of the groove in the direction perpendicular to the longitudinal direction of the grooves 1c, 3c, and 5c. Moreover, the width of the liquid supply port refers to the length of the liquid supply port in the direction perpendicular to the longitudinal direction of the liquid supply port.

[0022] In addition, gas such as helium or argon can be used instead of compressed air when inspecting for leaks. Also, the presence or absence of a leak can be determined by injecting a liquid such as ink into a liquid supply port with a groove and determining whether or not the ink is detected from a liquid supply port without a groove. In other words, any form is acceptable as long as it can supply a high-pressure fluid.

[0023] Furthermore, when only two liquid supply ports are formed, it is not possible to perform a leak test for all (two) liquid supply ports in a single test. This is because when compressed air is supplied to only one liquid supply port, it is not possible to detect a leak that exists only in the other liquid supply port, and when compressed air is supplied to both liquid supply ports, it is not possible to detect a leak that exists only between the two liquid supply ports. Therefore, the leak test method of the present invention can be applied to cases where at least three liquid supply ports are formed on a substrate.

[0024] Second embodiment The second embodiment will be described with reference to Fig. 2. The same parts as those in the first embodiment are given the same reference numerals and the description will be omitted. Fig. 2(a) is a top view of the substrate 14 in the second embodiment. Fig. 2(b) is a top view showing a modified example of the substrate 14 in the second embodiment.

[0025] In the first embodiment, the grooves 1c, 3c, and 5c are formed in the three liquid supply ports 1, 3, and 5, but in FIG. 2(a), the grooves 1c and 5c are formed only in the liquid supply ports 1 and 5, which are the liquid supply ports at both ends. Instead of forming the groove 3c in the liquid supply port 3, the grooves 1c and 5c are extended to a position where they overlap with the liquid supply port 3 in the x direction. By doing so, for example, even if there is a leak 103 occurring only in the liquid supply port 3, the leak 103 communicates with at least one of the grooves 1c and 3c, so that a pressure fluctuation occurs and the presence of the leak 103 can be detected. As a result, like the first embodiment, it is possible to inspect the presence or absence of leaks in all the liquid supply ports in a single inspection. In FIG. 2(a), it is sufficient to form two grooves 1c and 3c, so the number of grooves that need to be formed is smaller than in the first embodiment, and the manufacturing of the substrate 14 becomes easier.

[0026] 2(b), only groove 1c is formed in substrate 14. This groove 1c extends to a position where it overlaps with liquid supply port 5. In other words, when groove 1c extends from only one end of a plurality of liquid supply ports, it is necessary for groove 1c to extend to a position where it overlaps with the liquid supply port at the other end in the x direction. By forming fewer grooves, manufacturing of substrate 14 becomes even easier. [Explanation of symbols]

[0027] 1b~5b Discharge port 1c, 3c, 5c groove 1d~5d End of liquid supply port 13 Discharge port forming member 14 Substrate 17 Liquid ejection head 18 Outer edge of board 20 areas

Claims

1. a discharge port forming member that forms a discharge port for discharging liquid; a substrate supporting the ejection port forming member; having In the liquid ejection head, at least three liquid supply ports for supplying liquid to the ejection ports are formed in the substrate and arranged in an arrangement direction, a groove communicating with the end of the liquid supply port is formed in a region between an end of the liquid supply port in an extension direction in which the liquid supply port extends and an outer edge of the substrate that intersects with the extension direction, when viewed from a direction perpendicular to a main surface of the substrate; the groove extends from at least one end of one of the liquid supply ports located at both ends in the arrangement direction among the plurality of liquid supply ports, The liquid ejection head according to the present invention, wherein the groove extends at least to a position where there is an overlapping portion in the arrangement direction with another liquid supply port adjacent to the liquid supply port with which the groove communicates.

2. The liquid ejection head according to claim 1 , wherein the groove extends from each of the liquid supply ports located at both ends of the plurality of liquid supply ports.

3. The liquid ejection head according to claim 1 , wherein the groove extends only from a liquid supply port located at one end of the plurality of liquid supply ports, and extends to a position where it overlaps in the extension direction with the liquid supply port located at the other end.

4. 4. The liquid ejection head according to claim 1, wherein a depth of the groove from the main surface of the substrate is shallower than a depth of the liquid supply port from the main surface.

5. 5. The liquid ejection head according to claim 4, wherein the depth of the groove is equal to or less than one tenth of the depth of the liquid supply port.

6. 6. The liquid ejection head according to claim 1, wherein a width of the groove in a direction perpendicular to a longitudinal direction of the groove is smaller than a width of the liquid supply port in a direction perpendicular to the longitudinal direction of the liquid supply port.

7. 7. The liquid ejection head according to claim 6, wherein the width of the groove is equal to or smaller than half the width of the liquid supply port.

8. a discharge port forming member that forms a discharge port for discharging liquid; a substrate supporting the ejection port forming member; having A method for inspecting a liquid supply port of a liquid ejection head, the method comprising the steps of: preparing a substrate, in which a groove is formed in a region between an end of the liquid supply port in an extension direction of the liquid supply port and an outer edge of the substrate intersecting the extension direction, the groove communicating with the end of the liquid supply port, the groove extending to a position overlapping in the extension direction with another liquid supply port adjacent to the liquid supply port in which the groove is formed; supplying a high-pressure fluid into at least two liquid supply ports located at both ends of the plurality of liquid supply ports; opening to the atmosphere any of the liquid supply ports to which the fluid is not being supplied, among the plurality of liquid supply ports; measuring pressure fluctuations at a liquid supply port to which the fluid is supplied; 11. A method for inspecting a liquid supply port of a liquid ejection head for leaks, comprising:

9. 9. The method for inspecting a liquid supply port of a liquid ejection head for leaks according to claim 8, wherein the liquid supply ports to which the high-pressure fluid is supplied and the liquid supply ports to which the high-pressure fluid is not supplied are arranged alternately.

10. 10. The method for inspecting liquid supply ports of a liquid ejection head for leaks according to claim 8, wherein the grooves extend from the liquid supply ports located at both ends of the plurality of liquid supply ports.

11. A method for inspecting a liquid supply port of a liquid ejection head as described in claim 8 or 9, wherein the groove extends only from a liquid supply port located at one end of the plurality of liquid supply ports, and extends to a position where it overlaps in the extension direction with the liquid supply port located at the other end.

12. 12. The method for inspecting a liquid supply port of a liquid ejection head for leakage according to claim 8, wherein a depth of the groove from the main surface of the substrate is shallower than a depth of the liquid supply port from the main surface.

13. 13. The method for inspecting a liquid supply port of a liquid ejection head for leaks according to claim 12, wherein the depth of the groove is equal to or less than one tenth of the depth of the liquid supply port.

14. A method for inspecting a liquid supply port of a liquid ejection head as described in any one of claims 8 to 13, wherein the width of the groove in a direction perpendicular to the longitudinal direction of the groove is smaller than the width of the liquid supply port in a direction perpendicular to the longitudinal direction of the liquid supply port.

15. 15. The method for inspecting a liquid supply port of a liquid ejection head for leaks according to claim 14, wherein a width of the groove is equal to or smaller than half a width of the liquid supply port.

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