The present invention relates to a technique of ejecting liquid such as ink.
In the related art, a liquid ejecting head that ejects liquid such as ink supplied from a liquid storage chamber to a pressure chamber from a nozzle by generating pressure change in the pressure chamber has been proposed. In this type of liquid ejecting head, when pressure fluctuation occurs in the liquid storage chamber by liquid introduction into the liquid storage chamber and pressure change in the pressure chamber, the pressure may be transferred to the pressure chamber, which may cause an ejection failure of the liquid. For this reason, for example, in the liquid ejecting head disclosed in JP-A-2015-057315, a recessed portion constituting a liquid storage chamber (manifold) is closed and sealed with a flexible film (film) so that a portion of a wall surface is constituted of the flexible film. According to this configuration, the ejection failure is suppressed by absorbing the pressure fluctuation of the liquid storage chamber by bending the flexible film. Furthermore, in JP-A-2015-057315, a space is formed in which the flexible film bends on a side opposite to the liquid storage chamber with the flexible film interposed therebetween, and the space is communicated with an atmospheric vent (through-hole) via a communication passage extending around the liquid storage chamber. With this configuration, the air in the space in which the flexible film bends can enter and exit from the atmospheric vent according to the movement of the flexible film, so that the movement of the flexible film is facilitated.
However, in the configuration in which a communication passage that communicates a space in which a flexible film bends to the atmosphere is provided as in JP-A-2015-057315, since the cross-sectional area of the communication passage becomes smaller as the width of the communication passage becomes narrower, the air resistance increases, and thereby, it becomes difficult for the air in the space in which the flexible film bends to enter and exit from the atmosphere via the communication passage. Therefore, the flexible film becomes difficult to move and the effect of absorbing the pressure fluctuation of the liquid storage chamber is deteriorated. On the contrary, as the width of the communication passage becomes wider, since the flexible film exposed into the communication passage easily bends in the communication passage, the sealing property between the flow passage member and the flexible film is deteriorated in the region around the liquid storage chamber, and leak of liquid may occur.
An advantage of some aspects of the invention is to suppress deterioration of sealing property between a flow passage member and a flexible film around a liquid storage chamber while increasing an effect of absorbing pressure fluctuation of the liquid storage chamber.
According to an aspect of the invention, there is provided a flow passage structure including: a flow passage member that constitutes a portion of a wall surface of a liquid storage chamber; a flexible film that is laminated on the flow passage member and constitutes a portion of the wall surface of the liquid storage chamber; a sealing body that is laminated on a side opposite to the flow passage member with the flexible film interposed therebetween and forms a space in which the flexible film is exposed; communication passages that are formed in a region around the liquid storage chamber in the sealing body and causes the space to communicate with an atmosphere in a case where the sealing body is seen in a plan view from a direction in which the flow passage member and the flexible film are laminated; and a support portion that supports the flexible film in the communication passage. In this case, since the flexible film is supported by the support portion in the communication passage formed in the region around the liquid storage chamber that seals the flow passage member and the flexible film in the sealing body, even if the width of the communication passage is increased, it is difficult to bond the flow passage member with the flexible film exposed into the communication passage bends so that the deterioration of the sealing property can be suppressed.
“A region around the liquid storage chamber” is a region outside the liquid storage chamber in a plan view of the sealing body. For example, in a case where an opening penetrating the flow passage member constitutes a portion of the liquid storage chamber, a region overlapping the flow passage member constituting the opening corresponds to “a region around the liquid storage chamber”. The flexible film may not adhere to the flow passage member immediately above the support portion.
In the flow passage structure, it is preferable that in a cross section including the support portion among cross sections of the communication passages that intersect with a direction in which the communication passage extends, an area of a portion occupied by the support portion be smaller than an area of the other portions. In this case, since the area of the portion occupied by the support portion is smaller than the area of the other portions, the air resistance by the support portion can be reduced in the cross section including the support portion among the cross sections of the communication passage interesting with the direction in which the communication passage extends. For this reason, the air in the space in which the flexible film bends easily enters and exits from the atmosphere via the communication passage, and the movement of the flexible film exposed in the space of the sealing body is facilitated, so that the effect of absorbing the pressure fluctuation of the liquid storage chamber can be increased. In this case, it is possible to suppress deterioration of the sealing property between the flow passage member and the flexible film around the liquid storage chamber while increasing the effect of absorbing the pressure fluctuation of the liquid storage chamber.
In the flow passage structure, it is preferable that the communication passage communicate with the atmosphere via an atmospheric vent distanced from the liquid storage chamber, and a width of the communication passage in the cross section of the communication passage that intersects with the direction in which the communication passage extends be larger than a diameter of the atmospheric vent. In this case, since the width of the communication passage in the cross section of the communication passage which intersects the direction in which the communication passage extends is larger than the diameter of the atmospheric vent, the air resistance in the communication passage in the direction in which the communication passage extends can be reduced as compared with the case where the width of the communication passage is smaller than the diameter of the atmospheric vent.
In the flow passage structure, it is preferable that the atmospheric vent be a through-hole formed in the flexible film. In this case, since the width of the communication passage is larger than the diameter of the atmospheric vent formed in the flexible film, the air resistance in the communication passage in the direction in which the communication passage extends can be reduced as compared with the configuration in which the width of the communication passage is smaller than the diameter of the atmospheric vent.
In the flow passage structure, it is preferable that the atmospheric vent be formed in the flow passage member. In this case, since the atmospheric vent is formed in a flow passage member having a liquid storage chamber, it is easy to form the atmospheric vent away from the liquid storage chamber, so that it is possible to facilitate the routing of the communication passage. Moreover, since the width of the communication passage is larger than the diameter of the atmospheric vent formed in the flow passage member, the air resistance in the communication passage in the direction in which the communication passage extends can be reduced as compared with the configuration in which the width of the communication passage is smaller than the diameter of the atmospheric vent.
In the flow passage structure, it is preferable that the support portion be an island portion that is disposed in the communication passage. In this case, since the support portion is the island portion disposed in the communication passage, depending on the number, arrangement and shape of the island portions, the area of the portion occupied by the support portion can be made smaller than the area of the other portions, so that it is easy to reduce the air resistance in the communication passage.
In the flow passage structure, it is preferable that a plurality of the island portions be arranged side by side in a direction in which the communication passage extends. In this case, since a plurality of island portions are arranged side by side in the direction in which the communication passage extends, and the plurality of island portions overlap when viewed from that direction, the resistance in the direction in which the communication passage extends, that is, the direction through which air passes can be reduced.
In the flow passage structure, it is preferable that the support portion be a rail portion that projects into the communication passage from one or both sides of side surfaces of the communication passage facing each other. In this case, since the support portion is a rail portion projecting from one or both sides of side surfaces facing each other of the communication passage into the communication passage, depending on the number, arrangement, and shape of the rail portion, the area of the portion occupied by the support portion can be made smaller than the area of other portions, so that it is easy to reduce the air resistance in the communication passage.
In the flow passage structure, it is preferable that the width of the communication passage be ½ or more of a maximum width of a cross section of the space among cross sections of the communication passages that intersect with a direction in which the communication passage extends. In this case, by setting the width of the communication passage to be ½ or more of the maximum width of the space in the cross section of the communication passage which intersects the direction in which the communication passage extends, the air resistance in the communication passage in the direction in which the communication passage extends can be greatly reduced.
In the flow passage structure, it is preferable that the sealing body be constituted of a support plate that is laminated on the flexible film and a fixation plate that is laminated on the support plate on a side opposite to the flexible film, and the support portion support the flexible film that protrudes from the fixation plate toward the flexible film. In this case, since the support portion protrudes from the fixation plate toward the flexible film to support the flexible film, it is possible to suppress bending of the flexible film from the flow passage member into the communication passage.
In the flow passage structure, it is preferable that in a plan view of the sealing body, the communication passage be formed in a region corresponding to one end of the liquid storage chamber in the sealing body.
In the flow passage structure, it is preferable that a plurality of the liquid storage chambers be formed in the flow passage member, a plurality of the spaces each corresponding to the plurality of liquid storage chambers be formed in the sealing body, and the communication passage communicate with each of the spaces.
According to another aspect of the invention, there is provided a liquid ejecting head including: the flow passage structure according to an aspect; and a nozzle that ejects liquid supplied from the liquid storage chamber. In this case, it is possible to provide a liquid ejecting head provided with a flow passage structure capable of suppressing deterioration of the sealing property between the flow passage member and the flexible film around the liquid storage chamber while increasing the effect of absorbing the pressure fluctuation of the liquid storage chamber.
According to still another aspect of the invention, there is provided a liquid ejecting apparatus including: the liquid ejecting head according to another aspect; and a control device that causes the liquid ejecting head to eject liquid.
The invention will be described with reference to the accompanying drawings, wherein like numbers reference like elements.
The liquid container 14 is an ink tank type cartridge made of a box-shaped container attachable and detachable to and from the main body of the liquid ejecting apparatus 10. The liquid container 14 is not limited to a box-shaped container, and may be an ink pack type cartridge made of a bag-shaped container. Ink is stored in the liquid container 14. The ink may be black ink, or color ink. The ink stored in the liquid container 14 is pressurized and fed to the liquid ejecting head 20 by a pump (not shown).
The control device 12 integrally controls each element of the liquid ejecting apparatus 10. The transport mechanism 15 transports the medium 11 in a Y direction under the control of the control device 12. The liquid ejecting head 20 ejects ink supplied from the liquid container 14 from each of a plurality of nozzles N onto the medium 11 under the control of the control device 12.
The liquid ejecting head 20 is installed in the carriage 18. In
Liquid Ejecting Head
The nozzle plate 62 is a flat plate material constituting the ejection surface on which the plurality of nozzles N are arranged in the Y direction. The nozzle plate 62 is made of, for example, a silicon material. The plurality of nozzles N are formed of two rows of nozzle rows L1 and L2. Each of the nozzle rows L1 and L2 is an aggregation of the plurality of nozzles N arranged along the Y direction. The arrangement of the nozzle rows L1 and L2 is not limited to the one shown in the present embodiment. For example, each of the nozzle rows L1 and L2 may be arranged by being shifted in the Y direction. Moreover, the number of nozzle rows formed on the nozzle plate 62 is not limited to two, and may be one.
In the liquid ejecting head 20 according to the present embodiment, a structure corresponding to the nozzle row L1 (left portion of
The flow passage member 32 shown in
The laminated portion 38 is constituted by laminating the pressure chamber substrate 382 forming the pressure chambers SC communicating with the nozzles N, a vibration plate 384, and a protective plate 386 in this order. However, the invention is not limited to such a configuration, and the laminated portion 38 may be constituted without the protective plate 386. Moreover, the vibration plate 384 and the pressure chamber substrate 382 may be formed integrally. A plurality of opening portions 383 constituting the pressure chambers SC (cavities) communicating with each of the nozzles N are formed in the pressure chamber substrate 382. The pressure chamber substrate 382 is made of, for example, a silicon material similar to the flow passage member 32.
The vibration plate 384 is installed on a surface of the pressure chamber substrate 382 opposite to the flow passage member 32. The vibration plate 384 is an elastically vibratable flat plate material. The vibration plate 384 and the flow passage member 32 are opposed to each other with a gap therebetween inside each of the opening portions 383 formed on the pressure chamber substrate 382. The pressure chambers SC that generate pressure for ejecting ink from each of the nozzles N is constituted by a space interposed between the flow passage member 32 and the vibration plate 384 inside the opening portions 383 of the pressure chamber substrate 382. Each of the supply side communication flow passages 344 of the flow passage member 32 communicates the second liquid storage chamber 34 described later with the pressure chambers SC, and each of the nozzle side communication flow passages 326 of the flow passage member 32 communicates the pressure chambers SC with the nozzles N.
A plurality of piezoelectric elements 385 corresponding to different nozzles N (pressure chambers SC) are formed on the surface of the vibration plate 384 opposite to the pressure chamber substrate 382. Each of the piezoelectric elements 385 is a driving element in which a piezoelectric substance is interposed between electrodes facing each other. Each of the piezoelectric elements 385 individually vibrates by a drive signal supplied from the control device 12. The protective plate 386 is an element for protecting each of the piezoelectric elements 385, and is fixed on a surface of the pressure chamber substrate 382 (vibration plate 384) by, for example, an adhesive. Each of the piezoelectric elements 385 is stored in a recessed portion 387 formed on a surface of the protective plate 386 on the vibration plate 384 side. When each of the piezoelectric elements 385 vibrates according to the drive signal supplied from the control device 12, the vibration plate 384 vibrates in interlocking with the piezoelectric elements 385. As a result, the pressure of ink inside the pressure chambers SC fluctuates and the ink is ejected from the nozzles N. In this manner, the piezoelectric elements 385 function as pressure generating elements that fluctuate the pressure inside the pressure chambers SC to eject the ink inside the pressure chambers SC from the nozzles N. The piezoelectric elements 385 are connected with the control device 12 via a flexible printed cable (FPC: flexible printed circuit), a chip on film (COF) (not shown), or the like.
A surface of the case member 40 on a positive side in the Z direction (hereinafter, referred to as “bonding surface”) is fixed on a surface of the flow passage member 32 on a negative side of the Z direction by an adhesive, for example. The case member 40 is made of a molding resin material such as a plastic material. In a case where the case member 40 is made of a molding resin material, it can be molded integrally by an injection molding of the molding resin material. The case member 40 is a case for storing the ink supplied from the plurality of pressure chambers SC, and has a structure in which a first liquid storage chamber 42 that is communicated with the second liquid storage chamber 34 by the inflow port 342 as an opening portion. The first liquid storage chamber 42 communicates with an inlet 43 for introducing the ink.
Such a second liquid storage chamber 34 and first liquid storage chamber 42 are common spaces over the plurality of nozzles N, and store the ink supplied from the liquid container 14 in the inlet 43. The second liquid storage chamber 34 is formed of a space elongated in the Y direction. The second liquid storage chamber 34 of the present embodiment has a shape in which the flow passage is expanded from the inflow port 342 side toward the supply side communication flow passages 344 (outflow port) side. The plurality of pressure chambers SC are arranged in one direction (Y direction), and the plurality of supply side communication flow passages 344 are arranged along the arrangement of the plurality of pressure chambers SC in the Y direction.
As shown in
Flow Passage Structure
As shown in
The compliance plate 50 is fixed on the fixation plate 56. The fixation plate 56 is formed into a predetermined shape with a highly rigid material such as stainless steel. A plurality of opening portions 622 corresponding to each nozzle plate 62 are formed in the fixation plate 56, respectively. An opening portion 522 corresponding to the plurality of opening portions 622 is formed in the flexible film 52, and an opening portion 542 corresponding to the plurality of opening portions 622 is formed in the support plate 54. The support plate 54 of the compliance plate 50 is fixed on the fixation plate 56 so that the nozzle plate 62 is exposed from the opening portions 522, 542, and 562. A space inside the opening portions 522, 542, and 562 (specifically, a gap between the inner peripheral surfaces of the opening portions 522, 542, and 562 and an outer peripheral surface of the nozzle plate 62) is filled with a filler formed of, for example a resin material.
The positive side of the opening portion 541 of the support plate 54 in the Z direction is sealed with the fixation plate 56 by fixing the support plate 54 on the fixation plate 56, and the space interposed between the flexible film 52 and the fixation plate 56 inside the opening portion 541 becomes the above-described compliance space SG. The support plate 54 and the fixation plate 56 of the present embodiment function as a sealing body in which a space (compliance space SG) where the flexible film 52 is exposed is formed. In the present embodiment, the case where the sealing body is formed with the support plate 54 and the fixation plate 56 as separate bodies is exemplified. However, the invention is not limited thereto, and a sealing body may be formed by integrating the support plate 54 and the fixation plate 56 together. According to the compliance plate 50 constituted as described above, even if pressure fluctuation occurs in the liquid storage chamber SR, the pressure fluctuation can be absorbed by deformation of the flexible film 52. Since the opening portion 541 of the support plate 54 communicates with the atmosphere via the communication passage 544, the air inside the opening portion 541 can enter and exit from the atmosphere via the communication passage 544 according to the movement of the flexible film 52, so that the movement of the flexible film 52 is facilitated. The fixation plate 56 and the nozzle plate 62 may be formed integrally. In this case, the nozzles N may be formed on the fixation plate 56, and the opening portion 541 may be sealed with the nozzle plate 62.
Communication Passage
Here, a specific configuration example of the communication passage 544 that communicates the above-described opening portion 541 of the support plate 54 with the atmosphere will be described with reference to the drawings. As shown in
Since the cross-sectional area of the communication passage 544 that intersects with the direction (Y direction) in which the communication passage 544 extends becomes smaller as the width of the cross section is narrower, the air resistance increases, so that the air in the opening portion 541 hardly enters and exits from the atmospheric vent HA via the communication passage 544 when the flexible film 52 bends. Therefore, the flexible film 52 becomes difficult to move and the effect of absorbing the pressure fluctuation of the liquid storage chamber SR is deteriorated.
As a configuration of suppressing the air resistance of the communication passage 544, it is also conceivable to increase the thickness of the support plate 54 to secure the height of the cross section of the communication passage 544 sufficiently. However, in the configuration that the thickness of the support plate 54 is increased, since a surface of the fixation plate 56 approaches the medium 11, a possibility of the medium 11 coming into contact with the surface of the fixation plate 56 increases. On the other hand, it is possible to set the position of the liquid ejecting head 20 in the Z direction to secure a predetermined gap between the surface of the fixation plate 56 and the medium 11 in order to suppress the contact of the medium 11 with respect to the fixation plate 56. However, with the above-described configuration, the distance between the medium 11 and the nozzle plate 62 increases. Therefore, an error tends to occur at the position where the liquid ejected from the nozzles N land on the surface of the medium 11, and as a result, there is a possibility that the print quality may be deteriorated. Considering above circumstances, the configuration of reducing the air resistance by sufficiently securing the width of the communication passage 544 is more preferable than the configuration of securing the height of the communication passage 544.
As shown in
For example, it is found that dot omission occurs due to insufficient absorption of the pressure fluctuation of the liquid storage chamber SR in a print pattern in which solid ejection (when ejection duty is 100%), excitation (for example, case of repeating ejection (print) and non-ejection (blank) alternately), and solid ejection are continuous. Here, the ejection duty means the ratio of the ejected ink amount with respect to the maximum possible ink ejection amount per unit time.
Therefore, in the present embodiment, it is easy for the air in the opening portion 541 to enter and exit from the atmospheric vent HA via the communication passage 544 when the flexible film 52 bends by widening the width W of the communication passage 544. Accordingly, the movement of the flexible film 52 is facilitated, and it is possible to increase the effect of absorbing the pressure fluctuation of the liquid storage chamber SR. When the movement of the flexible film 52 is facilitated, the pressure fluctuation is absorbed by the movement of the flexible film 52 and the amplitude becomes smaller even if it is excited as shown in
However, as the width W of the communication passage 544 becomes wider, the flexible film 52 easily bends inside the communication passage 544 unless the flexible film 52 exposed into the communication passage 544 is not supported, so that the sealing property between the flow passage member 32 and the flexible film 52 around the liquid storage chamber SR is deteriorated.
As the width W becomes wider as the communication passage 544″ of
Operations and effects of the compliance plate 50 of the present embodiment will be described in detail with reference to the drawings.
As shown in
As shown in
As shown in
The two island portions constituting the support portion 545 of the present embodiment are disposed side-by-side in the direction (Y direction) in which the communication passage 544 extends toward the atmospheric vent HA. With this configuration, since the plurality of island portions overlap seen from the Y direction, the resistance in the direction in which the communication passage 544 extends, that is, the direction through which the air passes the communication passage 544 toward atmospheric vent HA can be reduced.
A case where each of the island portions constituting the support portion 545 of
A case where each of the island portions constituting the support portion 545 of
The number, arrangement, and shape (such as length, width, outer shape, thickness, size) of the island portions constituting the support portion 545 are not limited to the examples of the present embodiment. For example, the number of the each of the island portions may be increased to reduce the diameter as in a third modification example shown in
The shape of the communication passage 544 is not limited to the example of the first embodiment. The shape of the communication passage 544 may be changed according to the shape of the liquid storage chamber SR. For example, in the liquid storage chamber SR of a fourth modification example shown in
Since the end portion of the liquid storage chamber SR in
In
Each rail portion projects into the communication passage 544 from one side of two opposite side surfaces (negative side surface of the X direction and the positive side surface) of the communication passage 544. Each rail portion is connected to the side surface on one side of the communication passage 544 and is separated from the side surface opposed thereto. A thickness h′ of each rail portion is thinner than the thickness H of the support plate 54, and a gap is formed between the rail portion and the fixation plate 56. Therefore, the area of the portion occupied by the support portion 545 in the cross section P of the communication passage 544 can be reduced, so that the air resistance by the support portion 545 can be reduced. In the fifth modification example, the case where three rail portions protrude one by one alternately from the two opposite side surfaces of the communication passage 544 is exemplified, but the invention is not limited thereto. The rail portions may protrude alternately by two or more, or, they may not be alternately provided. The rail portion may protrude from only one of the two opposing side surfaces of the communication passage 544. The number, the arrangement and the shape (such as length, width, outer shape, thickness, size) of the rail portion are not limited to those illustrated in drawings.
A second embodiment of the invention will be described. For the elements having the same operations and functions as those in the first embodiment in the following examples, the reference numerals used in the description of the first embodiment are used, and the detailed description thereof is appropriately omitted. In the first embodiment, a case where one liquid storage chamber SR is continuous in the Y direction is exemplified. However, in the second embodiment, a case where a plurality of liquid storage chambers SR are arranged side by side in the Y direction will be exemplified.
In the configuration of
In the configuration of
Moreover, in the configuration of
In
The aspects and the embodiments exemplified above can be variously modified. Specific modes of modification are exemplified below. Two or more aspects randomly selected from the following examples and the above-described aspects can be appropriately merged within a range not inconsistent with each other.
(1) In the above-described embodiment, the serial head that reciprocally reciprocates the carriage 18 installed on the liquid ejecting head 20 along the X direction is exemplified. However, the invention is also applicable to a line head in which the liquid ejecting head 20 is disposed over the entire width of the medium 11.
(2) In the above-described embodiment, the piezoelectric type liquid ejecting head 20 using the piezoelectric element that applies the mechanical vibration to the pressure chamber is exemplified. However, it is also possible to adopt a thermal type liquid ejecting head using a heat generating element which generates bubbles inside the pressure chamber by heating.
(3) The liquid ejecting apparatus 10 exemplified in the above-described embodiment can be adopted for various apparatuses such as a facsimile apparatus and a copying machine in addition to the apparatus dedicated for printing. The application of the liquid ejecting apparatus 10 of the invention is not limited to printing. For example, a liquid ejecting apparatus that ejects a solution of a coloring material is used as a manufacturing apparatus that forms a color filter, an organic electro luminescence (EL) display, an FED (surface emitting display), and the like of a liquid crystal display apparatus. A liquid ejecting apparatus for ejecting a solution of a conductive material is used as a manufacturing apparatus for forming wirings and electrodes of a wiring substrate. It is also used as a chip manufacturing apparatus for ejecting a solution of a bioorganic matter as a kind of liquid.
This application claims priority to Japanese Patent Application No. 2017-250347 filed on Dec. 27, 2017 and Japanese Patent Application No. 2018-155602 filed on Aug. 22, 2018. The entire disclosures of Japanese Patent Application Nos. 2017-250347 and 2018-155602 are hereby incorporated herein by reference.
Number | Date | Country | Kind |
---|---|---|---|
2017-250347 | Dec 2017 | JP | national |
2018-155602 | Aug 2018 | JP | national |
Number | Name | Date | Kind |
---|---|---|---|
5963234 | Miyazawa et al. | Oct 1999 | A |
20060256159 | Owaki | Nov 2006 | A1 |
20150042719 | Fukuzawa et al. | Feb 2015 | A1 |
Number | Date | Country |
---|---|---|
H09-314836 | Dec 1997 | JP |
2015-036245 | Feb 2015 | JP |
2015-057315 | Mar 2015 | JP |
Number | Date | Country | |
---|---|---|---|
20190193400 A1 | Jun 2019 | US |