JP2008080742A - Liquid ejecting head and liquid ejecting apparatus - Google Patents

Abstract

A liquid ejecting head having increased rigidity against an external force of a nozzle plate is provided.
A rectangular plate-like reinforcing member 35 is fixed to the surface of a nozzle plate 20 corresponding to an ink chamber 15 forming a reservoir 1 by adhesion, and the reinforcing member 35 contacts a wall surface of an ink chamber 15 of a flow path forming substrate 10. Even if the nozzle plate 20 has no adhesive portion with the flow path forming substrate 10 over a wide area, the rigidity against the external force is increased to prevent peeling due to deformation.
[Selection] Figure 3

Description

  The present invention relates to a liquid ejecting head and a liquid ejecting apparatus that discharge liquid supplied from a fluid flow path to a pressure generating chamber, and in particular, a part of the pressure generating chamber that communicates with a nozzle is configured by a vibrating plate. The present invention relates to an ink jet recording head and an ink jet recording apparatus in which ink droplets are ejected from nozzles by displacement of a piezoelectric element provided thereon.

  Conventionally, a liquid ejecting head that ejects liquid droplets from a nozzle by applying pressure to the liquid by a piezoelectric element or a heat generating element is known, and a typical example thereof is ink jet recording that ejects ink droplets. A head is mentioned (for example, refer patent document 1).

  A conventional ink jet recording head includes a pressure conversion element for applying pressure to a pressure generating chamber of a flow path forming substrate, and a nozzle plate having nozzles for ejecting ink droplets on the lower surface of the flow path forming substrate Are joined (adhered). An ink flow path is provided in communication with the pressure generation chamber of the flow path forming substrate, and the pressure generation chamber on the opposite side of the nozzle plate is sealed with a bonding substrate. An opening is provided in the bonding substrate corresponding to the ink flow path, and a flexible sealing film member (sheet) for sealing the ink flow path is bonded to the opening.

  The nozzle plate is bonded to the lower surface of the reservoir portion constituted by the opening portion of the bonding substrate and the ink flow path portion of the flow path forming substrate, and the upper surface of the reservoir portion is covered with the sealing film member (sheet). ing. In the ink jet recording head, a rubber cap is pressed against the nozzle plate to cover the nozzle except during printing in order to protect the nozzle of the nozzle plate and clean the ink flow path.

JP 2006-21503 A (FIGS. 1 and 2)

  By the way, since the nozzle plate of the reservoir portion does not have an adhesive portion with the flow path forming substrate over a wide area, if the adhesive force of the nozzle plate is weakened due to long-term use or the like, the nozzle plate is caused by external force when pressing the cap. There was a risk of causing deformation and peeling. Although it is conceivable to increase the rigidity of the nozzle plate itself by increasing the thickness of the nozzle plate, it is difficult to form nozzles when the nozzle plate is increased in thickness.

  Such a situation exists not only in an ink jet recording head that ejects ink, but also in other liquid ejecting heads that eject ink other than ink.

  SUMMARY An advantage of some aspects of the invention is that it provides a liquid ejecting head and a liquid ejecting apparatus in which the nozzle plate is not deformed even when an external force is applied to the nozzle plate.

In order to achieve the above object, a first aspect of the present invention includes a flow path forming substrate on which a pressure generating chamber and a fluid flow path are formed, and joining the fluid flow path to one side of the flow path forming substrate. A bonding substrate having through holes formed in opposing portions, a nozzle plate provided on the other surface side of the flow path forming substrate and having a plurality of nozzles, and a side opposite to the pressure generation chamber side of the fluid flow path And a reinforcing member provided on the wall of the liquid jet head.
In the first aspect, since the reinforcing member is in contact with the wall portion of the fluid flow path, it is possible to increase the rigidity against the external force of the nozzle plate, and the nozzle having no adhesive portion with the flow path forming substrate over a wide area. Even if it is a plate, the external force by pressing a cap etc. works, and a deformation | transformation does not arise.
Although a conventional technique (for example, Japanese Patent Application Laid-Open No. 2001-121690) in which a step portion is formed on the ink supply path side of the reservoir is disclosed, the purpose of the similar technique in which the step portion is formed is that of the ink flowing into the reservoir. It is intended to smooth the flow, and is not intended to prevent the deformation of the nozzle plate by an external force acting on the nozzle plate. In the first place, the arrangement of the step portion of the prior art and the reinforcing member of the present invention is different.

According to a second aspect of the present invention, in the liquid ejecting head according to the first aspect, the reinforcing member is in contact with the wall surface of the fluid flow path, and is in contact with the wall surface of the opening of the bonding substrate from a portion in contact with the wall surface. The liquid ejecting head includes an extending portion extending in a horizontal direction.
In the second aspect, since the reinforcing member is provided with the extending portion that contacts the wall surface of the opening of the bonded substrate, the external force acting on the nozzle plate is dispersed on the wall surface of the bonded substrate, The rigidity can be further increased.

According to a third aspect of the present invention, in the liquid ejecting head according to the first aspect, the reinforcing member penetrates the wall portion on the opposite side of the pressure flow chamber side of the fluid flow path and is bonded onto the reinforcing member. In the liquid jet head, the substrate is attached.
In the 3rd mode, the rigidity to the external force of a nozzle plate can be raised because a part of wall part of a fluid channel of a channel formation substrate is constituted by a reinforcement member.

According to a fourth aspect of the invention, in the liquid ejecting head according to the third aspect, the reinforcing member is thicker than the thickness of the flow path forming substrate.
In the fourth aspect, since the reinforcing member is thicker than the thickness of the flow path forming substrate, the rigidity of the nozzle plate against the external force can be effectively increased.

According to a fifth aspect of the present invention, in the liquid jet head according to any one of the first to fourth aspects, the reinforcing member is in contact with a wall portion facing the wide portion of the fluid flow path. In the liquid jet head.
In the fifth aspect, since the reinforcing member is provided on the wall portion facing the wide portion of the fluid flow path, the rigidity of the nozzle plate against the external force can be reliably increased.

According to a sixth aspect of the present invention, in the liquid jet head according to any one of the first to fifth aspects, a plurality of pressure generation chambers are arranged in parallel on the flow path forming substrate, and each pressure generation chamber is common. In the liquid ejecting head, the pressure generating chamber and the fluid flow path are connected to each other through a communication path in which a part of the flow path width is narrowed.
In the sixth aspect, the rigidity against external force can be increased even with a nozzle plate that includes a communication path in which a part of the flow path width is narrowed and it is difficult to secure a bonding area.

In order to achieve the above object, a seventh aspect of the present invention is a liquid ejecting apparatus including the liquid ejecting head according to any one of the first to sixth aspects.
In the seventh aspect, a liquid ejecting apparatus having a liquid ejecting head that can increase the rigidity of the nozzle plate against an external force can be provided.

  The liquid ejecting head and the liquid ejecting apparatus of the present invention are a liquid ejecting head and a liquid ejecting apparatus in which the nozzle plate is not deformed even when an external force is applied to the nozzle plate.

  FIG. 1 is an exploded perspective view of an ink jet recording head as a liquid ejecting head according to the first embodiment of the present invention, and FIG. 2 is an ink jet recording as a liquid ejecting head according to the first embodiment of the present invention. FIG. 3 shows a schematic plan view of the head, FIG. 3 shows a schematic plan view of the reservoir portion of the flow path forming substrate, and FIG.

  As shown in the figure, the flow path forming substrate 10 constituting the ink jet recording head is composed of a silicon single crystal substrate having a crystal plane orientation of (110) in the present embodiment. A plurality of partitioned pressure generation chambers 12 are formed side by side in the width direction (vertical direction in FIG. 2).

  An ink supply path 13 and a communication path 14 that communicate with the pressure generation chamber 12 are formed on one end side (right side in FIGS. 2 and 3) of the pressure generation chamber 12 in the longitudinal direction of the flow path forming substrate 10, respectively. 13 and the communication path 14 are partitioned by the partition wall 11. The ink supply path 13 is formed to have a cross-sectional area narrower than that of the pressure generation chamber 12. An ink chamber 15 serving as a fluid flow path communicating with each communication path 14 is provided on the flow path forming substrate 10 opposite to the pressure generation chamber 12 with the ink supply path 13 interposed therebetween. The ink chamber 15 is a bonding substrate 30 described later. The reservoir portion 32 communicates with each other and forms a part of the common reservoir 1 of each pressure generating chamber 12.

  Since the ink supply path 13 is formed to have a narrower cross-sectional area than the pressure generation chamber 12, the flow path resistance of the ink flowing from the ink chamber 15 into the pressure generation chamber 12 is kept constant. For example, in this embodiment, the ink supply path 13 has a width smaller than the width of the pressure generation chamber 12 by narrowing the flow path on the pressure generation chamber 12 side between the reservoir 1 and each pressure generation chamber 12 in the width direction. Is formed.

  In this embodiment, the ink supply path 13 is formed by narrowing the width of the flow path from one side of the partition wall 11. However, the ink supply path may be formed by narrowing the width of the flow path from both sides of the partition wall 11. Good. In addition, the ink supply path may be formed by narrowing the cross-sectional area of the flow path from the thickness direction of the flow path forming substrate 10 instead of narrowing the width of the flow path.

  A nozzle plate 20 is fixed to the opening surface side (the lower surface side in FIGS. 1 and 3) of the flow path forming substrate 10 with an adhesive, a heat welding film, or the like, and a nozzle opening 21 is formed in the nozzle plate 20. . The nozzle openings 21 of the nozzle plate 20 are formed corresponding to the vicinity of the end of each pressure generating chamber 12 on the side opposite to the ink supply path 13. The nozzle plate 20 is made of, for example, glass ceramics, a silicon single crystal substrate, stainless steel, or the like.

  An elastic film 50 is provided on the side opposite to the opening surface of the flow path forming substrate 10 (the upper surface side in FIGS. 1 and 3). The elastic film 50 has a thickness of, for example, about 0.2 μm. An electrode film 60, a piezoelectric layer 70 having a thickness of, for example, about 0.5 to 3 μm, and an upper electrode film 80 having a thickness of, for example, about 0.1 μm are laminated to form a piezoelectric element 300. Yes. The piezoelectric element 300 refers to a portion including the lower electrode film 60, the piezoelectric layer 70, and the upper electrode film 80. In general, one electrode of the piezoelectric element 300 is used as a common electrode, and the other electrode and the piezoelectric layer 70 are patterned for each pressure generating chamber 12. A portion that is composed of any one of the patterned electrodes and the piezoelectric layer 70 and in which piezoelectric distortion is generated by applying a voltage to both electrodes is referred to as a piezoelectric active portion.

  In this embodiment, the lower electrode film 60 is a common electrode of the piezoelectric element 300, and the upper electrode film 80 is an individual electrode of the piezoelectric element 300. However, there is no problem even if this is reversed for the convenience of the driving IC and wiring. In either case, a piezoelectric active part is formed for each pressure generating chamber. Further, here, the piezoelectric element 300 and the diaphragm that is displaced by driving the piezoelectric element 300 are collectively referred to as a piezoelectric actuator. A lead electrode 90 is connected in the vicinity of one end in the longitudinal direction of the upper electrode film 80, which is an individual electrode of the piezoelectric element 300, and the lead electrode 90 is drawn out to the vicinity of the end of the flow path forming substrate 10 with a predetermined width. .

  On one surface side of the flow path forming substrate 10 on which the piezoelectric element 300 is formed, the bonding substrate 30 having the piezoelectric element holding portion 31 in which a space that does not hinder the movement of the piezoelectric element 300 is formed is formed. The piezoelectric element 300 is bonded and disposed in the piezoelectric element holding portion 31, but may be sealed or not sealed. Further, a through hole serving as a reservoir portion 32 is provided in a region of the bonding substrate 30 facing the ink chamber 15 of the flow path forming substrate 10, and the reservoir portion 32 penetrates the bonding substrate 30 in the thickness direction and is a pressure generation chamber. It is formed over 12 width directions. That is, the opening 33 is formed in the bonding substrate 30 at a portion corresponding to the ink chamber 15. As the bonding substrate 30, it is preferable to use a material substantially the same as the coefficient of thermal expansion of the flow path forming substrate 10, for example, glass, a ceramic material, and the like. It is formed using a crystal substrate. In the above description, the bonding substrate 30 has the piezoelectric element holding portion 31 and the opening 33 of the through hole serving as the reservoir portion 32 is described as one member covered with the sealing film 41. It is also possible to use a substrate having a substrate and a substrate in which the opening of the through-hole serving as the reservoir portion 32 is covered with a sealing film 41 as separate members, and handle the latter substrate as a “bonding substrate”. Further, the expression “on one side of the flow path forming substrate 10” is not limited to the form in which the flow path forming substrate 10 is directly bonded, and other expressions are provided between the flow path forming substrate 10 and the bonding substrate 30. To the point that a member of the above may be interposed.

  A driving IC 100 as a wiring member is provided on the upper surface of the bonding substrate 30 corresponding to the piezoelectric element holding portion 31, and the driving IC 100 is electrically connected to the lead electrode 90 to drive the piezoelectric element 300. A sealing film 41 as a sealing film member is bonded to the periphery of the opening 33 on the bonding substrate 30 with an adhesive. The periphery of the sealing film 41 is fixed on the bonding substrate 30 by a fixing plate 42.

  The sealing film 41 is made of a material having low rigidity and flexibility (for example, a polyphenylene sulfide (PPS) film having a thickness of 6 μm). Is sealed. The fixing plate 42 is formed of a hard material such as metal (for example, stainless steel (SUS) having a thickness of 30 μm). An area of the fixing plate 42 facing the reservoir portion 32 is an opening 43, and one surface (upper surface in FIG. 3) of the reservoir portion 32 is sealed only with a flexible sealing film 41.

  On the other hand, a rectangular plate-shaped reinforcing member 35 is fixed to the surface of the nozzle plate 20 corresponding to the ink chamber 15 constituting the reservoir 1 by adhesion, and the reinforcing member 35 contacts the wall surface of the ink chamber 15 of the flow path forming substrate 10. Is fixed. As shown in FIG. 4, the ink chamber 15 of the flow path forming substrate 10 includes a narrow portion existing in the vicinity of the end portion of the pressure generating chamber 12 in the row direction and a wide portion at a substantially central portion in the row direction. The reinforcing member 35 is in contact with the wall surface facing the wide portion. More specifically, the reinforcing member 35 is provided over substantially the entire length of the wide portion so that the wide portion faces the plurality of pressure generating chambers 12.

  Since the reinforcing member 35 is provided on the nozzle plate 20 in contact with the wall surface of the ink chamber 15, even when the nozzle plate 20 has no adhesive portion with the flow path forming substrate 10 over a wide area, the rigidity against external force is increased. Can be increased. Further, since the reinforcing member 35 is in contact with the entire length of the wall surface of the ink chamber 15 of the flow path forming substrate 10, the rigidity against external force can be reliably increased.

  For example, in order to protect the nozzle opening 21 of the nozzle plate 20 and to clean the ink flow path, as shown in FIG. 3, a rubber cap 36 is pressed against the nozzle plate 20 to cover the nozzle opening 21 except during printing. It is supposed to be. Since the cap 36 is made of rubber, which is an elastic member, an urging force is generated on the upper side (indicated by an arrow) in the drawing at the portion of the nozzle plate 20 to apply an external force. In particular, since the ink supply path 13 having a cross-sectional area narrower than that of the pressure generation chamber 12 is provided, deformation is likely to occur with the communication path 14 as a fulcrum. Therefore, the nozzle plate 20 does not deform and does not cause peeling even when the adhesive force is weakened.

  In the ink jet recording head of the present embodiment described above, ink is taken in from an ink introduction port connected to an external ink supply means (not shown), and the interior from the reservoir 1 to the nozzle opening 21 is filled with ink, and then from the drive IC 100. In accordance with the signal, a voltage is applied between each of the lower electrode film 60 and the upper electrode film 80 corresponding to the pressure generation chamber 12 to bend and deform the piezoelectric element 300, thereby increasing the pressure in each pressure generation chamber 12. Ink droplets are ejected from the nozzle openings 21.

  Second to fourth embodiments of the present invention will be described. FIG. 5 is a sectional view of an ink jet recording head according to a second embodiment of the present invention, FIG. 6 is a sectional view of an ink jet recording head according to a third embodiment of the present invention, and FIG. FIG. 8 shows a cross-sectional view of an ink jet recording head according to the fourth embodiment of the present invention. The second to fourth embodiments are different from the first embodiment in the configuration of the reinforcing member, and FIGS. 5, 6, and 8 correspond to FIG. 3 of the first embodiment. FIG. 7 shows a situation corresponding to FIG. 4 of the first embodiment. For this reason, the same members as those in the first embodiment are denoted by the same reference numerals, and the entire configuration of the ink jet recording head is omitted.

  A second embodiment will be described with reference to FIG.

  The surface of one rectangular portion 52 of a reinforcing member 51 having an L-shaped angle member shape is adhered and fixed to the surface of the nozzle plate 20 corresponding to the ink chamber 15 forming the reservoir 1, and the other rectangular shape of the reinforcing member 51 is fixed. The portion 53 is in contact with the wall surface of the opening 33 (reservoir portion 32) of the bonding substrate 30 from the wall surface of the ink chamber 15 of the flow path forming substrate 10. That is, the reinforcing member 51 has one rectangular portion 52 that contacts the wall surface of the ink chamber 15 and the other rectangular portion that extends from the rectangular portion 52 to the wall surface of the opening 33 and extends toward the bonding substrate 30. 53.

  In the ink jet recording head of the second embodiment, the reinforcing member 51 has a rectangular portion 53 that contacts the wall surface of the opening 33 (reservoir portion 32) of the bonding substrate 30 from the wall surface of the ink chamber 15 of the flow path forming substrate 10. Is provided. The ink chamber 15 has a narrow portion that exists in the vicinity of the end of the pressure generating chamber 12 in the row direction, and a wide portion that is a substantially central portion in the row direction. Similarly to the first embodiment, the reinforcing member 51 including the reinforcing member 51 is provided over substantially the entire length of the wide portion so as to face the plurality of pressure generating chambers 12 in the wide portion. Therefore, the external force acting on the nozzle plate 20 is dispersed on the wall surface of the bonding substrate 30, and the rigidity of the nozzle plate 20 with respect to the external force is increased even if the nozzle plate 20 has no adhesive portion with the flow path forming substrate 10 over a wide area. It can be further increased.

  A third embodiment will be described with reference to FIGS.

  A rectangular plate-like reinforcing member 55 is fixed to the surface of the nozzle plate 20 corresponding to the ink chamber 15 forming the reservoir 1 by adhesion, and the reinforcing member 55 is an ink chamber of the flow path forming substrate 10 on the opposite side of the pressure generating chamber 12. The bonding substrate 30 (elastic film 50) is attached to the upper surface through the 15 wall portions. As shown in FIG. 7, the reinforcing member 55 is provided so as to penetrate the wall portion over the entire length of the wall portion facing the wide portion of the ink chamber 15 of the flow path forming substrate 10. The bonding substrate 30 is bonded onto the wide reinforcing member 55.

  In the ink jet type recording head of the third embodiment, a part of the wall portion of the ink chamber 15 of the flow path forming substrate 10 is constituted by the reinforcing member 55, so that the adhesive portion with the flow path forming substrate 10 over a wide area. Even if the nozzle plate 20 does not exist, the rigidity against external force can be increased.

  A fourth embodiment will be described with reference to FIG.

  A rectangular plate-shaped reinforcing member 57 is fixed to the surface of the nozzle plate 20 corresponding to the ink chamber 15 constituting the reservoir 1 by adhesion, and the reinforcing member 57 is an ink chamber of the flow path forming substrate 10 on the opposite side of the pressure generating chamber 12. The bonding substrate 30 (elastic film 50) is attached to the upper surface through the 15 wall portions. The reinforcing member 57 is thicker than the thickness of the flow path forming substrate 10 constituting the pressure generating chamber 12. The ink chamber 15 has a narrow portion that exists in the vicinity of the end of the pressure generating chamber 12 in the row direction and a wide portion at a substantially central portion in the row direction, and the reinforcing member 51 is the same as in the first embodiment. The reinforcing member 57 is provided over almost the entire length of the wide portion so as to face the plurality of pressure generating chambers 12 in the wide portion.

  In the ink jet recording head of the fourth embodiment, a part of the wall portion of the ink chamber 15 of the flow path forming substrate 10 is configured by the reinforcing member 57 that is thicker than the thickness of the flow path forming substrate 10. The ink chamber 15 has a narrow portion existing in the vicinity of the end portion of the pressure generating chamber 12 in the row direction and a wide portion at a substantially central portion in the row direction, and the reinforcing member 57 is also the same as that of the first embodiment. Similarly, the reinforcing member 57 is provided over substantially the entire length of the wide portion so that the wide portion faces the plurality of pressure generating chambers 12. Therefore, even if the nozzle plate 20 has no adhesive portion with the flow path forming substrate 10 over a wide area, the rigidity against the external force can be effectively increased.

  Similarly to the ink jet recording head of the first embodiment, the ink jet recording head of the second to fourth embodiments does not deform the nozzle plate 20 even when it is pushed by a cap for suction or the like. Even when the adhesive strength is weakened, it does not cause peeling.

  The recording head described above is mounted on an ink jet recording apparatus as a liquid ejecting apparatus. An outline of the ink jet recording apparatus will be described with reference to FIG.

  As shown in the figure, the recording heads 8A and 8B having the recording head main body are detachably provided with cartridges 2A and 2B constituting the ink supply means, and the recording heads 8A and 8B are mounted on the carriage 3. A carriage shaft 5 is attached to the apparatus body 4, and the carriage 3 on which the recording heads 8 </ b> A and 8 </ b> B are mounted is provided on the carriage shaft 5 so as to be movable in the axial direction. The driving force of the driving motor 6 is transmitted to the carriage 3 via a plurality of gears (not shown) and the timing belt 7, and the carriage 3 on which the recording heads 8 A and 8 B are mounted is moved along the carriage shaft 5. On the other hand, the apparatus body 4 is provided with a platen 9 along the carriage shaft 5, and a recording sheet S which is a recording medium such as paper fed by a paper feed roller (not shown) is conveyed on the platen 9.

  In the above-described embodiment, the ink jet recording head that discharges ink droplets is described as an example of the liquid ejecting head. However, the present invention can be widely applied to all liquid ejecting heads. For example, as a liquid ejecting head, for forming electrodes such as a recording head used in an image recording apparatus such as a printer, a color material ejecting head used for manufacturing a color filter such as a liquid crystal display, an organic EL display, and an FED (field emission display). An electrode material ejecting head used, a bioorganic matter ejecting head used for biochip production, or the like can be applied.

2 is an exploded perspective view of an ink jet recording head. FIG. 1 is a schematic plan view of an ink jet recording head. It is the III-III arrow directional view in FIG. It is a schematic plan view of a reservoir portion of a flow path forming substrate. It is principal part sectional drawing of the example of 2nd Embodiment. It is principal part sectional drawing of the example of 3rd Embodiment. It is a schematic plan view of the third embodiment. It is principal part sectional drawing of the example of 4th Embodiment. It is the schematic of a recording device.

Explanation of symbols

  8A, 8B recording head, 10 flow path forming substrate, 30 bonding substrate, 35, 51, 55, 57 reinforcing member

Claims (7)

A flow path forming substrate in which a pressure generating chamber and a fluid flow path are formed;
A bonded substrate having a through hole formed in a portion facing the fluid flow channel and bonded to one side of the flow channel forming substrate;
A nozzle plate provided on the other surface side of the flow path forming substrate and having a plurality of nozzles formed thereon;
A liquid ejecting head comprising: a reinforcing member provided on a wall portion opposite to the pressure generating chamber side of the fluid flow path. The liquid ejecting head according to claim 1,
The reinforcing member includes an extending portion that contacts the wall surface of the fluid flow path and extends from a portion that contacts the wall surface to contact the wall surface of the opening of the bonding substrate. The liquid ejecting head according to claim 1,
The liquid ejecting head, wherein the reinforcing member passes through a wall portion of the fluid flow path opposite to the pressure generating chamber side, and a bonding substrate is attached to the reinforcing member. The liquid ejecting head according to claim 3,
The reinforcing member is thicker than the thickness of the flow path forming substrate. The liquid ejecting head according to claim 1,
The reinforcing member is in contact with a wall portion facing the wide portion of the fluid flow path. In the liquid jet head according to any one of claims 1 to 5,
A plurality of pressure generation chambers are arranged in parallel on the flow path forming substrate, and each pressure generation chamber is connected to a common fluid flow path, and a part of the flow path width is narrowed between the pressure generation chamber and the fluid flow path. A liquid ejecting head characterized by communicating with each other through a communication path.   A liquid ejecting apparatus comprising the liquid ejecting head according to claim 1.

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