Liquid discharge head

Abstract

A liquid discharge head is provided that can quickly discharge a variety of liquids without increasing the size. The liquid discharge head includes a plurality of inlet portions corresponding to the variety of liquids, a plurality of pressure chambers in which discharge pressure is applied to the liquids, a plurality of individual outlet portions through which the liquids are supplied to the pressure chambers, and a manifold that communicates with the plurality of inlet portions and through which the liquids from the plurality of inlet portions are supplied to the plurality of individual outlet portions. The manifold includes a plurality of upstream side portions in each of which a passage corresponding to one of the plurality of inlet portions is defined, and a downstream side portion that communicates with the plurality of upstream side portions and in which a passage that communicates with the plurality of individual outlet portions is defined.

Description

Technical Field

[0001] This disclosure relates to a liquid discharge head configured to discharge or eject a liquid such as ink. Background Technology

[0002] Image recording devices, such as inkjet printers, include liquid discharge heads for discharging ink. For example, Patent Document 1 discloses a configuration in which a three-port valve (a valve having a detergent inlet port, an ink inlet port, and an ink outlet port) is inserted into a circulation channel connected to the liquid discharge head. Ink or detergent is supplied to the liquid discharge head by switching the ports as needed. Thus, the interior of the liquid discharge head is cleaned with detergent. Patent Document 2 discloses a configuration in which the supply of different types of ink is switched in a supply channel upstream of a reservoir located in the liquid discharge head. In this configuration, multiple types of ink can be discharged or ejected from a single liquid discharge head.

[0003] [List of Citations]

[0004] [Patent Literature]

[0005] Patent Document 1: Japanese Patent Application Publication No. 2008-012819

[0006] Patent Document 2: Japanese Patent Application Publication No. 2012-200948 Summary of the Invention

[0007] Technical issues

[0008] However, the liquid discharge head in Patent Document 1 does not disclose any structure for switching the supply of different inks (e.g., pigments and dyes). Therefore, multiple liquid discharge heads are required when discharging different types of ink. This increases the number of parts or components in the liquid discharge head, resulting in a larger size of the liquid discharge device. In the structure of Patent Document 2, the liquid supply is switched in the supply channel of the liquid discharge head, and ink remaining in all channels (supply channel, reservoir, and individual channels) is discharged (discharged) before another ink is introduced into the liquid discharge device. This takes a long time. Furthermore, ink clumps may remain in O-rings or similar components provided in the supply channel, which can lead to color mixing.

[0009] In view of this, the object of this disclosure is to provide a liquid discharge head that can quickly discharge a variety of liquids without increasing the size of the liquid discharge head.

[0010] [Solution to the problem]

[0011] According to one aspect of this disclosure, the liquid discharge head includes:

[0012] Multiple inlets are provided, each of the multiple inlets corresponding to each of the multiple liquids;

[0013] Multiple pressure chambers, in which a discharge pressure is applied to the liquid;

[0014] Multiple individual outlets supply the liquid to the multiple pressure chambers; and

[0015] A manifold, which communicates with the plurality of inlets and supplies the liquid from the plurality of inlets to the plurality of individual outlets.

[0016] The manifold includes:

[0017] A plurality of upstream sides, each of which defines a channel corresponding to one of the plurality of inlet sections; and

[0018] A downstream side, which communicates with the plurality of upstream sides, and defines a channel in the downstream side that communicates with the plurality of individual outlets.

[0019] According to this disclosure, the manifold is formed by multiple upstream sides corresponding to multiple inlets and a downstream side shared by the multiple upstream sides. Therefore, multiple liquid discharge heads are not required. This prevents an increase in the size of the device or equipment. Furthermore, switching mechanisms such as three-port valves are not required, thus reducing the size of the structure used for switching the liquid supply. In conventional devices, prior ink remaining in a long channel, including a supply channel, a reservoir, and a separate channel, needs to be drained before subsequent ink is introduced into the device. In the liquid discharge head of this disclosure, the liquid supply switching can be performed on a side further downstream than in conventional structures. Therefore, the time required to drain the prior liquid remaining in the channel can be shortened, and subsequent liquid can be introduced into the downstream side of the manifold immediately after draining the prior liquid remaining in the channel through its corresponding inlet. Thus, multiple liquids can be drained quickly. Furthermore, the liquid supply switching can be performed on the upstream side of the manifold, so the liquid channel can be shorter than in conventional devices. This results in a smaller amount of residual liquid compared to conventional devices. Therefore, it is possible to reduce the area in which the liquid mixes (color mixing area) and reduce the amount of liquid discharged (discharge).

[0020] [Beneficial effects of the invention]

[0021] According to this disclosure, a liquid discharge head is provided that can quickly discharge a variety of liquids without increasing the size of the liquid discharge head. Attached Figure Description

[0022] Figure 1 This is a plan view of a liquid discharge head according to an embodiment of the present disclosure.

[0023] Figure 2 It is along Figure 1 The cross-sectional view taken from line II-II in the diagram.

[0024] Figure 3A yes Figure 2 A plan view of the side of the manifold, and Figure 3B yes Figure 3A A side view of the manifold side.

[0025] Figure 4A It is along Figure 3A A cross-sectional view taken from line IVA-IVA in the diagram. Figure 4B It is along Figure 3A The cross-sectional view of line IVB-IVB in the middle, and Figure 4C It is along Figure 3A A cross-sectional view taken from line IVC-IVC in the diagram.

[0026] Figure 5A yes Figure 3A A plan view of the modified side of the manifold, and Figure 5B yes Figure 5A A side view of the manifold side.

[0027] Figure 6A It is along Figure 5A The cross-sectional view taken by line VIA-VIA in the middle, and Figure 6B It is along Figure 5A The cross-sectional view taken by line VIB-VIB in the diagram.

[0028] List of reference numerals

[0029] 14: Pressure chamber; 28: Nozzle; 28a: Nozzle orifice; 30: Inlet; 30A: Cleaning agent inlet; 33: Upstream side; 34: Downstream side; 35: Connecting part; 36: Manifold; 36a: Separate outlet; 39: Pressure chamber side; 40: Manifold side; 41: Openable / closeable valve; 45: Damper; 100: Liquid discharge head; D1: Front-back direction; D2: Left-right direction; D3: Up-down direction Detailed Implementation

[0030] Referring to the accompanying drawings, a liquid discharge head according to an embodiment of the present invention is explained below. The liquid discharge head described below is merely an embodiment of the present invention. Therefore, the present invention is not limited to the following embodiments. Additions, deletions, and modifications can be made without departing from the spirit or essential characteristics of the present invention.

[0031] [First Embodiment]

[0032] <Schematic diagram of liquid discharge head>

[0033] In the corresponding figures, D1 indicates the front-back direction (arrangement direction), D2 indicates the left-right direction (axial direction) orthogonal to the front-back direction D1, and D3 indicates the up-down direction orthogonal to the front-back direction D1 and the left-right direction D2.

[0034] The liquid discharged or ejected from the liquid discharge head 100 according to an embodiment of the present disclosure includes, for example, pigments (pigment ink), dyes (dyed ink), pretreatment agents, and posttreatment agents. The pretreatment agents are used to improve the fixing properties of the liquid (ink), while the posttreatment agents are used to improve abrasion resistance.

[0035] like Figure 1 and Figure 2 As shown, when separated in the left-right direction D2, the liquid discharge head 100 of this embodiment is formed by a pressure chamber side 39 and a manifold side 40. Figure 1 and Figure 2 In the middle, the manifold side 40 is located on the right side of the pressure chamber side 39.

[0036] The pressure chamber side 39 includes: a lead electrode 12; a piezoelectric element 20 disposed corresponding to the nozzle 28 described below; an elastic membrane 26; a channel forming substrate 27; and a protective substrate 29. The channel forming substrate 27 is also used in the manifold side 40. Details of the manifold side 40 are described below. Each piezoelectric element 20 includes a piezoelectric body layer 23, an upper electrode film 24, and a lower electrode film 25.

[0037] The details of the construction of the pressure chamber side 39 will be explained first. Then the details of the construction of the manifold side 40 will be explained.

[0038] The protective substrate 29 is formed of silicon, for example. The protective substrate 29 has, for example, an inverted U-shape (inverted concave shape). This provides a placement space 13 for arranging the piezoelectric element 20 on the underside of the protective substrate 29. The piezoelectric element 20 is arranged in the placement space 13.

[0039] An elastic membrane 26 is disposed between the protective substrate 29 and the portion included in the channel forming substrate 27 that forms the pressure chamber side 39. The elastic membrane 26 is formed, for example, of silicon dioxide. The thickness of the elastic membrane 26 is 1 to 2 μm. A lower electrode membrane 25, a piezoelectric layer 23, and an upper electrode membrane 24 are formed and stacked on the elastic membrane 26. In this embodiment, the lower electrode membrane 25 serves as the common electrode of the piezoelectric element 20, while the upper electrode membrane 24 serves as a separate electrode of the piezoelectric element 20. However, this is not a limitation. Depending on the convenience of wiring, the lower electrode membrane 25 may be formed to serve as a separate electrode, while the upper electrode membrane 24 may be formed to serve as a common electrode. Furthermore, the elastic membrane 26 and the lower electrode membrane 25 serve as a vibrating plate.

[0040] The area on the right side of the protective substrate 29 is space 11. The lead electrode 12 is formed, for example, of gold. The first end of the lead electrode 12 is connected to the upper electrode film 24 of the corresponding piezoelectric element 20. The second end of the lead electrode 12 is disposed on the lower side of space 11.

[0041] The channel forming substrate 27 is formed, for example, from a silicon single-crystal substrate. A nozzle plate 43 is stacked on the lower surface of the channel forming substrate 27. The nozzle plate 43 extends above the pressure chamber side 39 and the manifold side 40. The portion of the channel forming substrate 27 that forms the pressure chamber side 39 is provided with a liquid supply channel 37, which communicates with a corresponding individual outlet 36a of the downstream side portion 32 (described below), the pressure chamber 14, and the nozzle 28. The liquid supply channel 37 and the pressure chamber 14 form a separate channel 38. The individual outlet 36a of the downstream side portion 32 (described below) is connected to the inlet of the corresponding liquid supply channel 37. The outlet of the liquid supply channel 37 communicates with the corresponding pressure chamber 14. The nozzle 28 is formed in the nozzle plate 43. The upstream end of the nozzle 28 communicates with the corresponding pressure chamber 14, and its downstream end is a nozzle orifice 28a.

[0042] The construction details of the manifold side 40 in the liquid discharge head 100 are then explained. The manifold side 40 includes: an upstream side portion (upstream side structure) 31 and a downstream side portion (downstream side structure) 32 forming a liquid channel; and a manifold partition wall 42. The downstream side portion 32 is included in the channel forming substrate 27 and forms part of the manifold side 40.

[0043] For example, the upstream side portion 31 is formed into a basic cylindrical shape by injection molding. The downstream side portion 32 is formed into a basic cylindrical shape, for example, by wet etching. Thus, the upstream side portion 33 is formed as a spatial region in the upstream side portion 31, and the downstream side portion 34 is formed as a spatial region in the downstream side portion 32. The downstream side portion 32 is bonded to the upstream side portion 31. The upstream side portion 31 and the downstream side portion 32 are thus integrally formed. The lower end surface of the upstream side portion 31 is flush with the lower surface of the elastic film 26. The upper end surface of the downstream side portion 32 is flush with the upper surface of the channel forming substrate 27. The upstream side portion 31 is formed, for example, by resin. The upstream side portion 33, the downstream side portion 34, and the connecting portion 35 described below form a manifold 36.

[0044] In this embodiment, such as Figure 3A As shown, two inlet portions 30 are provided on the upper surface of the upstream portion 31. The inlet portions 30 are arranged offset from each other along the front-rear direction D1 (the direction in which the separate outlet portion 36a, described below, is arranged). Furthermore, the inlet portions 30 are arranged offset from each other in the left-right direction D2, which is orthogonal to the front-rear direction D1. That is, one inlet portion 30 is arranged at a predetermined interval from the other inlet portion 30 in the front-rear direction D1. Furthermore, one inlet portion 30 is arranged at a predetermined interval from the other in the left-right direction D2.

[0045] like Figure 3B As shown, a separate outlet 36a is provided in the downstream side portion 32 of the manifold side portion 40. Specifically, the separate outlet 36a is provided in the side surface of the downstream side portion 32 on one side of the manifold 36 in the short side or in the lateral direction (i.e., the left-right direction D2). That is, the separate outlet 36a is arranged in the front-back direction D1.

[0046] Corresponding inlets 30 are provided for various liquids. Specifically, for example, a liquid pigment flows into one inlet 30, and a liquid dye flows into another inlet 30. More specifically, the liquid pigment flows into the inlet 30 included in the inlet 30 and closer to the individual outlet 36a. Figure 3A The inlet 30 is located on the lower side of the inlet. Liquid dye flows into the inlet 30, which is included in the inlet 30 and is further away from the separate outlet 36a. Figure 3A (Entrance 30 on the upper side). The dyes and pigments have, for example, the same color.

[0047] The inlet 30 is arranged to overlap with the manifold 36 in the plan view. That is, the manifold 36 is located directly below the inlet 30. Each inlet 30 communicates with a corresponding upstream side 33 of the manifold 36. That is, the upstream side 33 of the manifold 36 corresponds to the inlet 30, and one upstream side 33 is separated from the other by the manifold partition wall 42, thereby forming different channels. Thus, in this embodiment, some areas of the manifold 36 (i.e., the two upstream sides 33) are defined or separated by the manifold partition wall 42.

[0048] like Figure 2 As shown, the manifold partition wall 42 is formed such that the central portion 42a in the left-right direction D2 protrudes downward beyond the rest of its portion. In the manifold partition wall 42, the lower surface of the central portion 42a is positioned higher than the joint surface between the upstream side portion 31 and the downstream side portion 32. Therefore, a connecting portion 35, through which the lower portion of one upstream side portion 33 communicates with the lower portion of the other upstream side portion 33, is formed in the region below the central portion 42a of the manifold partition wall 42. That is, according to this embodiment, not only the two upstream side portions 33 serving as different channels, but also the connecting portion 35, serving as a common channel for pigments and dyes, are formed in the upstream side portion 31. The connecting portion 35 communicates with the downstream side portion 34 formed through the downstream side portion 32.

[0049] The downstream side 34 is connected to the corresponding upstream side 33 via the connecting part 35. That is, the downstream side 34 is a common area of ​​the upstream side 33. The downstream side 34 is connected to a separate outlet 36a. The separate outlet 36a is connected to a corresponding liquid supply channel 37 in the pressure chamber side 39. Therefore, the liquid in the downstream side 34 is supplied to the corresponding liquid supply channel 37 in a distributed manner via the separate outlet 36a.

[0050] An opening 43a is provided in the portion included in the nozzle plate 43 and located below the downstream portion 32. A damper 45 is formed to cover the opening 43a of the nozzle plate 43 from below. The thickness of the damper 45 is less than the thickness of the nozzle plate 43. The damper 45 is located below the inlet portion 30. Therefore, the pressure of the liquid from the inlet portion 30 is absorbed by the damper 45, and then the liquid flows into the liquid supply channel 37 via a separate outlet portion 36a.

[0051] In the liquid discharge head 100 with the above-described structure, liquid from a tank (not shown) is supplied to a manifold 36 through an inlet 30. The liquid from the inlet 30 is then supplied to a separate outlet 36a through the manifold 36. The area including the manifold 36, the liquid supply channel 37, the pressure chamber 14, and the nozzle 28 is then filled with liquid. In this state, a drive voltage is applied to the upper electrode film 24 corresponding to the respective pressure chamber 14 via lead electrodes 12 based on a drive signal from a drive IC (not shown). In this configuration, the piezoelectric layer 23 contracts in the planar direction along with the upper electrode film 24 and the lower electrode film 25 depending on the drive signal. This applies a discharge pressure to the pressure chamber 14, through which liquid is discharged from the nozzle 28. Consequently, the pressure in the pressure chamber 14 increases, thereby discharging droplets from the nozzle orifice 28a of the nozzle 28.

[0052] Referring to the accompanying drawings, the detailed construction of the manifold side 40 in this embodiment is explained. Figure 4A It is along to Figure 3A The cross-sectional view taken from line IVA-IVA in the diagram. Figure 4B It is along Figure 3A A cross-sectional view taken from line IVB-IVB in the diagram. Figure 4C It is along Figure 3A A cross-sectional view taken from line IVC-IVC in the diagram.

[0053] like Figure 4A and Figure 4B As shown, the interior space of each inlet 30 has a shape that widens from its upper part to its lower part (in terms of diameter), for example, a flared shape (i.e., the circumferential surface defining the inlet has a shape that widens in diameter from the inflow side to the outflow side). Such a widened portion (flared portion) may, for example, include a portion formed as at least one of a cone shape and an arc shape.

[0054] The channel of the upstream side 33 of the manifold 36 includes a portion formed as at least one of a conical shape and an arc shape. Specifically, as Figure 3A As shown, corresponding to Figure 4A The inlet port 30 of the upstream side 33 shown is provided on the first side in the front-rear direction D1. Figure 3A and Figure 4A (on the left side of the middle). Therefore, in Figure 4A In the channel of the upstream side 33 shown, when from Figure 4A When viewed in the cross-sectional view, its right side (i.e., the area to the right of the entrance 30) extends further from top to bottom in the front-rear direction D1 than its left side (i.e., the area to the left of the entrance 30). On the other hand, as Figure 3A As shown, corresponding to Figure 4B The inlet port 30 of the upstream side 33 is located on the second side in the front-rear direction D1. Figure 3A and Figure 4A (on the right side of the middle). Therefore, in Figure 4B In the channel of the upstream side 33 shown, when from Figure 4B When viewed in the cross-sectional view, its left side extends further from the top to the bottom in the front-back direction D1 than its right side.

[0055] exist Figure 4A and Figure 4B In this configuration, the maximum length of the upstream side 33 in the longitudinal direction D1 is shorter than the maximum length of the downstream side 34 in the longitudinal direction D1. In other words, because the maximum length of the downstream side 34 in the longitudinal direction D1 is longer than that of the upstream side 33, a height difference (step) protruding towards the inside of the manifold 36 is prevented from forming between the upstream side 33 and the downstream side 34. This prevents liquid from stagnating at the step.

[0056] Each inlet 30 is provided with an on / off valve (two-way valve) 41. The on / off valve 41 can switch its position between an open position and a closed position. In the open position, the valve 41 allows liquid to flow downstream, and in the closed position, the flow of liquid towards the downstream side is blocked by the valve 41. The on / off valve 41 can be, for example, any of the following: a valve using a piezoelectric element, a solenoid valve, and a ball valve.

[0057] In the above embodiments, the concept or terminology of inlet 30 includes an opening (space) and a portion (wall) forming or defining the opening. Similarly, the concept or terminology of individual outlet 36a includes an opening (space) and a portion (wall) forming or defining the opening, while the concept or terminology of manifold 36 includes an opening (space) and a portion (wall) forming or defining the opening.

[0058] As explained above, in the liquid discharge head 100 of this embodiment, the manifold 36 is formed by an upstream side 33 corresponding to the corresponding inlet 30 and a downstream side 34 shared by the corresponding upstream side 33. Therefore, it is not necessary to provide multiple liquid discharge heads corresponding to the types of liquids to be discharged. This prevents an increase in the size of the discharge device including the liquid discharge head 100. Furthermore, since a switching mechanism such as a three-port valve is not required, the size of the structure used for switching the liquid supply can be reduced. In conventional devices, before introducing subsequent liquid into the device, it is necessary to drain (discharge) the previous liquid remaining in a long channel, which includes a supply channel, a reservoir, and a separate channel. However, in the liquid discharge head 100 of this embodiment, compared to conventional structures, the switching of the liquid supply can be performed on a more downstream side. Therefore, the time required to drain (discharge) the remaining previous liquid can be shortened, and after draining the previous liquid, subsequent liquid can be immediately introduced into the manifold 36 through its corresponding inlet 30. Therefore, multiple liquids can be discharged quickly. Furthermore, the liquid supply can be switched at the upstream side 33 of the manifold 36, thus the liquid passage (i.e., the area where the liquid needs to be replaced) can be shorter than the liquid passages in conventional devices. This results in a smaller amount of residual liquid in the liquid discharge head 100 of this disclosure compared to conventional devices. Consequently, the area where the liquid mixes (color mixing area) can be reduced, and the amount of residual liquid discharged (discharge rate) can be decreased.

[0059] In this embodiment, since the internal space of the inlet 30 has a shape that widens from top to bottom (in terms of diameter), liquid can flow into it smoothly.

[0060] In this embodiment, since the channel forming the upstream side 33 of the manifold 36 includes a portion formed as at least one of a cone shape and an arc shape, this allows liquid to flow smoothly into it.

[0061] In this embodiment, the corresponding inlet 30 is arranged to overlap with the manifold 36 in a plan view. In other words, the manifold 36 is arranged directly below the corresponding inlet 30. In this configuration, liquid from the inlet 30 can easily flow into the manifold 36.

[0062] In this embodiment, the respective inlet portions 30 are arranged offset from each other in the arrangement direction D1 (the direction in which the individual outlet portion 36a is arranged). Furthermore, the inlet portions 30 are arranged offset from each other in the left-right direction D2, which is orthogonal to the front-back direction D1. That is, one inlet portion 30 and the other inlet portion 30 are arranged at predetermined intervals in the front-back direction D1 and the left-right direction D2. In this configuration, supply connectors for supplying liquid to the respective inlet portions 30 can be easily arranged.

[0063] In this embodiment, a damper 45 is formed on the downstream side of the downstream portion 32. The damper 45 is disposed below the inlet portion 30. In this configuration, liquid introduced from each inlet portion 30 can be guided to the liquid supply channel 37 while the pressure of the liquid introduced from the inlet portion 30 is absorbed by the damper 45.

[0064] In this embodiment, an openable / closeable valve 41 is provided at the corresponding inlet 30. The state in which liquid is allowed to flow downstream and the state in which the flow of liquid toward the downstream side is blocked can be switched by the openable / closeable valve 41, that is, the switching is achieved by a simple construction.

[0065] In this embodiment, the structure of the openable / closeable valve 41 is not complicated by using any of the valves that use piezoelectric elements, such as valves, solenoid valves, ball valves, etc.

[0066] In this embodiment, the liquid discharged from the liquid discharge head 100 includes pigments, dyes, pretreatment agents, and posttreatment agents. As described above, even in the liquid discharge head 100 that discharges four types of liquids, multiple liquids can be discharged rapidly.

[0067] In this embodiment, by discharging dyes and pigments that have the same color, color mixing caused by dyes and pigments can be reduced or prevented. Furthermore, even when dyes and pigments are mixed, the color mixture is not noticeable because the dyes and pigments have the same color.

[0068] Furthermore, in this embodiment, the liquid pigment flows into an inlet 30 closer to the individual outlet 36a. Figure 3A The inlet 30 is located on the lower side of the channel. Pigment tends to stagnate in the channel. Therefore, as described above, the pigment flows into the inlet 30 closer to the individual outlet 36a, and into the inlet 30 further away from the individual outlet 36a. Figure 3A Compared to the case where the inlet 30 is located at the upper side, the channel length from the inlet 30 to the individual outlet 36a is shortened. Therefore, in this embodiment, it is less likely that the pigment will stagnate in the channel.

[0069] In this embodiment, the connecting portion 35 is configured to allow communication between the lower portion of the upstream side 33 corresponding to one inlet 30 and the lower portion of the upstream side 33 corresponding to the other inlet 30. In this configuration, not only the downstream side 34 serves as a common channel, but the connecting portion 35 also serves as a common channel. This increases the volume of the common channel for the liquid.

[0070] In this embodiment, the manifold 36 is formed by integrally joining the upstream side portion 31 that forms the upstream side portion 33 and the downstream side portion 32 that forms the pressure chamber 14, the liquid supply channel 37 and the downstream side portion 34 to the channel forming substrate 27. This construction is simple and increases the volume of the manifold 36.

[0071] In this embodiment, the maximum length of the upstream side 33 in the longitudinal direction D1 is shorter than the maximum length of the downstream side 34 in the longitudinal direction D1. Therefore, a height difference (step) protruding towards the interior of the manifold 36 is prevented from forming between the upstream side 33 and the downstream side 34. This prevents liquid from stagnating at the step, allowing for a smooth downward supply of liquid.

[0072] <Second Embodiment>

[0073] The liquid discharge head according to the second embodiment is described below. Although the liquid discharge head 100 of the first embodiment has two inlets 30, the liquid discharge head of the second embodiment has three inlets (i.e., two inlets 30 and one detergent inlet 30A). Those components or parts that are the same as or equivalent to those in the first embodiment are named by the same reference numerals, and any explanation thereof is omitted as necessary.

[0074] like Figure 5B As described above, similar to the first embodiment, the manifold side 40A of this embodiment includes an upstream side portion 31A and a downstream side portion 32A. In such... Figure 5A In the manifold side portion 40A of the second embodiment shown, the upper part of the upstream side portion 31A is provided with two inlet portions 30 and a detergent inlet portion 30A. Similarly, in the second embodiment, the inlet portions 30 are arranged offset from each other in the front-rear direction D1. Furthermore, the inlet portions 30 are arranged offset from each other in the left-right direction D2. The detergent inlet portion 30A is located between one inlet portion 30 and the other in the front-rear direction D1 and the left-right direction D2. In this configuration, each of the adjacent inlet portions 30 and the detergent inlet portion 30A is arranged at a predetermined interval along the front-rear direction D1 and the left-right direction D2.

[0075] In the second embodiment, inlet portions 30 and cleaning agent inlet portions 30A are respectively provided for the three liquids. Specifically, for example, the pigment, as a liquid, is located on the first side in the front-rear direction D1 ( Figure 5A The dye flows into the inlet 30 from the left side of the middle section, and is at the second side of the front-rear direction D1 as a liquid dye. Figure 5A The detergent (from the right side) flows into the inlet 30. Additionally, the liquid detergent flows into the detergent inlet 30A. Similar to the first embodiment, the dye and pigment can have the same color in the second embodiment.

[0076] The inlet 30 is arranged to overlap with the manifold 36 in the plan view. That is, the manifold 36 is located directly below the inlet 30. Here, the inlet 30 on the first side in the longitudinal direction D1 and the inlet 30 on the second side in the longitudinal direction D1 are respectively connected to the corresponding upstream side 33 of the manifold 36. At the same time, as Figure 6B As shown, the manifold partition wall 50 defines: an upstream side 33 on the left side in the left-right direction D2, communicating with the inlet 30 on the first side in the front-rear direction D1; and an upstream side 33 on the right side in the left-right direction D2, communicating with the inlet 30 on the second side in the front-rear direction D1. Although the manifold partition wall 50 is similar in shape to the manifold partition wall 42 in the first embodiment, the difference between the manifold partition wall 50 and the manifold partition wall 42 is that, along... Figure 6B A through-hole portion 51 extending in the vertical direction D3 is formed at the center of the manifold partition wall portion 50 in the horizontal direction D2. The upper end of the through-hole portion 51 communicates with the detergent inlet portion 30A, which is located at the center in the front-rear direction D1, as described above. Therefore, liquid from the detergent inlet portion 30A located at the center flows through the through-hole portion 51 and then flows into the connecting portion 35 of the manifold 36.

[0077] Referring to the accompanying drawings, the detailed structure of the manifold side portion 40A of the second embodiment will be explained.

[0078] like Figure 6A As shown, the channel forming the through-hole portion 51 communicating with the detergent inlet portion 30A extends symmetrically from the upper side to the lower side in the front-rear direction D1, such that the lower part of the channel is longer in the front-rear direction D1 than the upper part of the channel is longer in the front-rear direction D1. (This is in contrast to the first side in the front-rear direction D1...) Figure 5A The shape of the upstream side portion 33 (the shape of the upstream side portion 31) connected to the entrance portion 30 at the left side of the first embodiment is similar to that of the first embodiment (see [reference]). Figure 4A The shape of the upstream side portion 33 (the shape of the upstream side portion 31) is the same as that of the second side in the front-rear direction D1. Figure 5A The shape of the upstream side portion 33 (the shape of the upstream side portion 31) connected to the entrance portion 30 at the right side of the first embodiment is similar to that of the first embodiment (see the right side of the first embodiment). Figure 4B The shape of the upstream side portion 33 (the shape of the upstream side portion 31) is the same.

[0079] Figure 6AThe maximum length of the through-hole portion 51 in the longitudinal direction D1 is shorter than the maximum length of the downstream side portion 34 in the longitudinal direction D1. In other words, since the maximum length of the downstream side portion 34 in the longitudinal direction D1 is longer than the maximum length of the through-hole portion 51 in the longitudinal direction D1, a height difference (step portion) protruding towards the interior of the manifold 36 is prevented from forming between the through-hole portion 51 and the downstream side portion 34. This prevents liquid from stagnating at the step portion.

[0080] In the second embodiment, the concept or terminology of the through-hole portion 51 includes a hole (space) and a portion (wall) that forms or defines the hole.

[0081] Therefore, similar to the first embodiment, the size increase of the discharge device including the liquid discharge head 100 of the second embodiment is suppressed. Furthermore, similar to the first embodiment, multiple liquids can be discharged quickly, and the size of the structure used for switching liquid supplies can be reduced. Furthermore, similar to the first embodiment, the amount of residual liquid in the second embodiment is less than that in conventional devices. Therefore, the area in which liquids mix (color mixing area) can be reduced, and the amount of residual liquid discharged (discharge rate) can be reduced.

[0082] In the second embodiment, since the cleaning agent can flow into the cleaning agent inlet 30A, multiple portions of the manifold 36 (particularly the connecting portion 35 and the downstream side portion 34) can be cleaned quickly. Furthermore, since the cleaning agent inlet 30A is located between the inlet 30 on the left and the inlet 30 on the right, cleaning agent can be supplied throughout the entire manifold 36 in the front-rear direction D1. Therefore, the connecting portion 35 and the downstream side portion 34 can be cleaned quickly.

[0083] <Other Embodiments>

[0084] This invention is not limited to the embodiments described above, and various modifications can be made to this invention without departing from its spirit or essential characteristics. For example, the following variations can be made.

[0085] In the above embodiments, the manifold 36 is formed by integrally joining the upstream side portion 31 and the connecting portion 35 that form the upstream side portion 33, and the downstream side portion 32 that forms the downstream side portion 34. However, this disclosure is not limited thereto. The manifold 36 may be formed from a single component or portion.

[0086] In the above embodiment, a damper 45, which is a component distinct from the nozzle plate 43, is disposed below the inlet 30. However, this disclosure is not limited thereto. For example, the damper 45 can be formed, for instance, by performing a half-etch on the nozzle plate 43.

[0087] In the above embodiment, the manifold partition wall 42 is formed from a single component. However, this disclosure is not limited thereto. The manifold partition wall 42 can be formed by joining two components that are separated at the center in the left-right direction D2.

[0088] In the above embodiment, the interval between the entrance portion 30 (the interval in the front-back direction D1 and the interval in the left-right direction D2) is a regular interval. However, this disclosure is not limited thereto, and one or both of the intervals in the front-back direction D1 and the left-right direction D2 may not be regular intervals.

[0089] In the above embodiments, the interior space of each inlet 30 has a shape that widens (in diameter) from its upper part to its lower part. However, this disclosure is not limited thereto. The interior space of each inlet 30 may have, for example, a straight shape in which the upper and lower parts have the same diameter.

[0090] In the above embodiment, by providing a manifold partition wall portion 42, a connecting portion 35 is formed between the upstream side portion 33 and the downstream side portion 34, such that the lower surface of the central portion of the manifold partition wall portion 42 is located at a position higher than the joint surface between the upstream side portion 31 and the downstream side portion 32. However, providing the connecting portion 35 is not essential.

[0091] In the above embodiments, two or three inlets (inlet 30 and detergent inlet 30A) are provided to allow various liquids to flow through them. However, this disclosure is not limited thereto. Four or more inlets may be provided.

[0092] In the above embodiment, the cleaning agent, as a liquid, flows into the cleaning agent inlet 30A. However, this disclosure is not limited thereto. For example, any other liquid, such as a pretreatment agent or a posttreatment agent, may flow into the cleaning agent inlet 30A.

Claims

1. A liquid discharge head, comprising: Multiple inlets are provided, each of the multiple inlets corresponding to each of the multiple liquids; Multiple pressure chambers, in which a discharge pressure is applied to the liquid; Multiple individual outlets supply the liquid to the multiple pressure chambers; and A manifold, which communicates with the plurality of inlets and supplies the liquid from the plurality of inlets to the plurality of individual outlets. The manifold includes: Multiple upstream sides, each of which defines a channel corresponding to one of the multiple inlet sides; and A downstream side, which communicates with the plurality of upstream sides, and defines a channel in the downstream side that communicates with the plurality of individual outlets. The plurality of upstream sides include a first upstream side and a second upstream side, each extending in the arrangement direction of the plurality of individual outlets. The plurality of individual outlets are disposed in the side surface of the manifold on one side in the short-side direction of the manifold, the short-side direction being orthogonal to the arrangement direction, and The first upstream side and the second upstream side are adjacent to each other in the short side direction.

2. The liquid discharge head according to claim 1, wherein the internal space of each of the plurality of inlets has a shape that widens from the upper part of the internal space toward the lower part of the internal space.

3. The liquid discharge head according to claim 1 or 2, wherein the channel defined in each of the plurality of upstream sides of the manifold includes a portion having at least one of a conical shape and an arc shape.

4. The liquid discharge head according to claim 1 or 2, wherein the plurality of inlets are arranged to overlap with the manifold in a plan view.

5. The liquid discharge head according to claim 1 or 2, wherein the plurality of inlets are arranged to be offset from each other in the arrangement direction.

6. The liquid discharge head according to claim 1 or 2, wherein the plurality of inlets are arranged to be offset from each other in the short-side direction orthogonal to the arrangement direction.

7. The liquid discharge head according to claim 1 or 2, further comprising a damper, the damper being thin and disposed below the plurality of inlets.

8. The liquid discharge head according to claim 1 or 2, wherein each of the plurality of inlets is provided with a two-way valve configured to switch between an open position and a closed position, wherein in the open position the valve allows each of the liquids to flow downstream, and in the closed position the valve blocks the downstream flow of each of the liquids.

9. The liquid discharge head according to claim 8, wherein the valve is any one of a valve using a piezoelectric element, a solenoid valve, and a ball valve.

10. The liquid discharge head according to any one of claims 1, 2 and 9, wherein the plurality of liquids comprises at least two of pigments, dyes, pretreatment agents and posttreatment agents.

11. The liquid discharge head according to claim 10, wherein the color of the dye and the color of the pigment are the same as each other.

12. The liquid discharge head according to any one of claims 1, 2, 9 and 11, wherein the pigment, as a liquid, flows into one of the plurality of inlets, the one inlet being closer to the plurality of individual outlets than the other inlets are closer to the plurality of individual outlets.

13. The liquid discharge head according to any one of claims 1, 2, 9 and 11, further comprising a communication portion communicating with a lower portion of an upstream side of one of a plurality of upstream sides of an inlet corresponding to the inflow of a pigment as a liquid, and the communication portion communicating with a lower portion of an upstream side of one of a plurality of upstream sides of an inlet corresponding to the inflow of a dye as a liquid.

14. The liquid discharge head according to any one of claims 1, 2, 9 and 11, wherein the manifold is formed by integrally joining the upstream side structures forming the plurality of upstream sides and the downstream side structures forming the downstream sides.

15. The liquid discharge head according to any one of claims 1, 2, 9 and 11, wherein the maximum length of each of the plurality of upstream sides in the arrangement direction is shorter than the maximum length of the downstream side in the arrangement direction.

16. The liquid discharge head according to any one of claims 1, 2, 9 and 11, further comprising a detergent inlet connected to the manifold, the detergent inlet being an inlet for detergent to flow into the manifold.

17. The liquid discharge head according to claim 16, wherein the cleaning agent inlet is disposed between one inlet and another inlet arranged in the longitudinal direction of the manifold among the plurality of inlets.

18. The liquid discharge head according to claim 1, wherein a wall extending in the arrangement direction of the plurality of individual outlets separates the first upstream side and the second upstream side from each other.

19. The liquid discharge head of claim 18, wherein the surface defining the top of the first upstream side slopes downwards with respect to a corresponding inlet of the plurality of inlets, and the surface defining the top of the second upstream side slopes downwards with respect to a corresponding inlet of the plurality of inlets.

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