JP5716893B2 - Liquid ejecting head and liquid ejecting apparatus - Google Patents

Description

  The present invention relates to a liquid ejecting head and a liquid ejecting apparatus that eject liquid from nozzle openings, and more particularly to an ink jet recording head and an ink jet recording apparatus that eject ink as liquid.

  In an ink jet recording head which is an example of a liquid ejecting head, a pressure change is generated in a pressure generating chamber communicating with a nozzle opening, and ink droplets are ejected from the nozzle opening.

  Here, some ink jet recording heads are provided with a valve unit (back pressure control unit) (see, for example, Patent Document 1).

JP 2007-260948 A

  Such a back pressure control unit includes a cover that can be divided and a flow path member provided inside the cover, and a seal member such as rubber is held at the boundary of the divided cover. .

  However, the sealing member of the back pressure control unit is used to seal the divided area of the cover divided by itself, to seal the opening of the serpentine opening that opens in a groove shape, and around the connection port to which the external liquid storage means is connected. Therefore, the sealing area that is the seam of the outer periphery of the cover, the sealing area of the opening of the serpentine, and the sealing area around the connection port must all be arranged at the same height. In other words, there is a problem that the degree of freedom of arrangement is low and the back pressure control unit is enlarged.

  In addition, since the sealing member seals three sealing regions as a single unit, the sealing member has a complicated shape and needs to position the sealing member, so that the assembly work is complicated and the sealing member is poorly positioned. There is a problem that ink leakage may occur.

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

  In view of such circumstances, the present invention can reduce the number of parts to reduce material cost and assembly cost, and can be miniaturized and can suppress liquid leakage. The purpose is to provide.

An aspect of the present invention that solves the above problems includes a head main body that ejects liquid, and a back pressure control unit to which the head main body is fixed, and the back pressure control unit includes a cover that can be divided on the outer periphery. A flow path member held in a holding portion inside the cover, and the cover includes a base portion and a cover portion fixed to the base portion, and the base portion and the cover portion. The flow path member has a groove-like serpentine opening on the cover portion side, a connection port to which an external supply pipe is connected, and the connection A liquid flow path that communicates with the mouth and supplies the liquid to the head body, and the cover portion is provided in a region in contact with the base portion of the outer peripheral edge portion to seal the holding portion. A first seal portion that seals and an opening on the cover portion side of the meandering passage A seal portion and a third seal portion that seals a gap between the periphery of the connection port and the cover portion are arranged separately, and the cover portion, the first seal portion, and the second seal portion And the third seal portion is formed by two-color molding.
In such an aspect, the number of parts can be reduced by integrating the cover portion, the first seal portion, the second seal portion, and the third seal portion by two-color molding. Further, the positioning of the cover portion and each seal portion is not necessary, so that the assembly can be simplified and the liquid leakage due to the displacement of the seal portion can be suppressed. Further, by separating the first seal portion, the second seal portion, and the third seal portion, the seal portions can be arranged at different heights of the cover portion, so that an unreasonable design of the back pressure control unit is possible. It becomes unnecessary and can be reduced in size.

  Here, it is preferable that the first seal portion, the second seal portion, and the third seal portion are provided at positions having different heights in the cover portion. According to this, the distance between the seal portions can be increased to reliably suppress the leakage of the liquid, and an unreasonable design of the back pressure control unit is not required, and the size can be reduced.

  Moreover, it is preferable that the flow path member is configured by laminating a plurality of plate-like members. According to this, a complicated liquid flow path can be formed easily and at low cost, and downsizing can be achieved by the complicated liquid flow path.

According to another aspect of the invention, there is provided a liquid ejecting apparatus including the liquid ejecting head according to the above aspect.
According to this aspect, it is possible to realize a liquid ejecting apparatus that is improved in reliability by suppressing liquid leakage and reduced in size.

FIG. 2 is an exploded perspective view of a recording head according to Embodiment 1 of the invention. It is an exploded perspective view of a channel member concerning Embodiment 1 of the present invention. It is sectional drawing of the back pressure control unit which concerns on Embodiment 1 of this invention. It is a principal part disassembled perspective view of the back pressure control unit which concerns on Embodiment 1 of this invention. It is the top view and sectional view of a cover part concerning Embodiment 1 of the present invention. It is the figure which expanded the top view and principal part of the protection board which concern on Embodiment 1 of this invention. 1 is a schematic perspective view of a recording apparatus according to Embodiment 1 of the present invention.

Hereinafter, the present invention will be described in detail based on embodiments.
(Embodiment 1)
FIG. 1 is an exploded perspective view of an ink jet recording head that is an example of a liquid jet head according to Embodiment 1 of the present invention, FIG. 2 is an exploded perspective view of a flow path member, and FIG. 4 is a sectional view of the control unit, FIG. 4 is an exploded perspective view of the main part of the back pressure control unit, FIG. 5 is a plan view of the cover part and its AA ′ sectional view, and FIG. It is the figure which expanded the top view and principal part of a protection board.

  As shown in FIG. 1, an ink jet recording head 10 which is an example of a liquid ejecting head according to Embodiment 1 of the present invention includes a back pressure control unit 20 and a circuit board 60 provided on the bottom surface of the back pressure control unit. A head case 70 provided on the opposite side of the circuit board 60 from the back pressure control unit 20 and a plurality of head main bodies 80 fixed to the head case 70 are provided.

  The back pressure control unit 20 supplies ink from a liquid storage means such as an ink tank in which external ink is stored to the head body 80.

  Here, the back pressure control unit 20 will be described in detail. The back pressure control unit 20 includes a cover 30 made of a hollow box-shaped member, and a flow path member 40 provided inside the cover 30.

  The cover 30 includes a base portion 31 and a cover portion 32 that are divided vertically. The base portion 31 is provided with a first holding portion 311 having a concave shape opening to the cover portion 32 side, and a wiring insertion hole 312 provided on one end portion side of the first holding portion 311 and penetrating in the thickness direction. And a support portion 313.

  In addition, a plurality of supply ports 314 are provided on the bottom surface of the first holding portion 311 of the base portion 31 to supply ink to the head body through the thickness direction. In the present embodiment, seven supply ports 314 are provided on the bottom surface of the base portion 31.

  As shown in FIGS. 1 and 4, the cover portion 32 has a size that covers the first holding portion 311 of the base portion 31, and faces the first holding portion 311 of the base portion 31 so as to face the base portion 31. A second holding portion 321 having a concave shape opening in

  As shown in FIG. 3, the base portion 31 and the cover portion 32 are fixed so that the first holding portion 311 and the second holding portion 321 face each other, so that the first holding portion 311 and the inside are connected to each other. It has the holding part 33 which is a space defined by the second holding part 321.

  Here, the base portion 31 is provided with a first wall portion 315 that defines a side surface of the first holding portion 311. The cover portion 32 is provided with a second wall portion 322 that defines the side surface of the second holding portion 321. The base portion 31 and the cover portion 32 are fixed by bringing the distal end surface of the first wall portion 315 and the distal end surface of the second wall portion 322 into contact with each other.

  At this time, as will be described in detail later, a first seal portion 34 made of rubber, elastomer, or the like is sandwiched between the first wall portion 315 and the second wall portion 322.

  The cover portion 32 is provided with an opening 323 that communicates with the bottom surface of the second holding portion 321 and penetrates in the thickness direction. The opening 323 opens to the outer peripheral surface of the cover part 32 and is provided on the bottom surface of the second holding part 321 and protrudes lower than the second wall part 322 that defines the side surface of the second holding part 321. An opening is provided in the portion 324.

  As shown in FIGS. 2 and 3, the flow path member 40 held by the holding portion 33 of the cover 30 is, in the present embodiment, the first flow path member 41 provided on the base portion 31 side and the first flow member. A second flow path member 42 provided on the path member 41, a pressure chamber forming member 43 provided on the second flow path member 42, and a protective plate 44 provided on the pressure chamber forming member 43. It is configured by stacking.

  Each of the first flow path member 41, the second flow path member 42, the pressure chamber forming member 43, and the protection plate 44 is formed of a plate-like member made of a resin material, a metal material, or the like. The first flow path member 41, the second flow path member 42, the pressure chamber forming member 43, and the protection plate 44 are held in the holding portion 33 of the cover 30 in a stacked state.

  In the first flow path member 41, the second flow path member 42, and the pressure chamber forming member 43 constituting the flow path member 40, the ink from the liquid storage means in which external ink is stored is supplied to the head main body 80. A liquid flow path 50 for supply is provided.

  Specifically, as shown in FIG. 3, the liquid flow path 50 is a connection port to which the other end of a supply pipe (not shown) that is a tubular member such as a tube having one end connected to the liquid storage means is connected. 51, a chamber 53 to which ink from the introduction channel 52 is supplied, and a supply channel 54 to supply the ink from the chamber 53 to the head body 80.

  Here, the connection port 51 is provided on the upper surface of the second flow path member 42 so as to open into the opening 323 of the cover portion 32. A plurality of such connection ports 51 are provided corresponding to a plurality of inks. In the present embodiment, seven connection ports 51 are provided (see FIGS. 1 and 2).

  The introduction path 52 having such a connection port 51 is formed between the second flow path member 42 and the first flow path member 41, or between the second flow path member 42 and the first flow path member 41. It is comprised by the flow path, the flow path between the 1st flow path member 41 and the base part 31, etc.

  Here, the introduction path 52 of the present embodiment includes two paths, a first introduction path 55 shown in FIG. 3A and a second introduction path 56 shown in FIG.

  As shown in FIG. 3A, the first introduction channel 55 includes a first introduction channel 551 that penetrates the second channel member 42 and the first channel member 41 in the thickness direction, and a first channel. A second introduction channel 552 that is formed in a concave shape on the bottom surface of the member 41 and has one end communicating with the first introduction channel 551, and a first channel that communicates with the other end of the second introduction channel 552. The first introduction chamber 553 provided through the member 41 and the first filter chamber provided between the first passage member 41 and the second passage member 42 and communicating with the third introduction passage 553. 554 and a fourth introduction channel 555 provided in communication with the first filter chamber 554 and penetrating through the second channel member 42.

  As shown in FIG. 3B, the second introduction path 56 includes a fifth introduction path 561 that communicates with the connection port 51 and penetrates the second flow path member 42 in the thickness direction, and a first flow path member. A sixth introduction channel 562 having a concave shape provided between 41 and the second channel member 42, a first filter chamber 563 communicating with the sixth introduction channel 562, and communicating with the first filter chamber 563. And a seventh introduction channel 564 provided through the second channel member 42 in the thickness direction.

  That is, the first introduction path 55 passes between the first flow path member 41 and the base portion 31 and reaches the chamber 53. In contrast, the second introduction path 56 passes between the first flow path member 41 and the second flow path member 42 without passing between the first flow path member 41 and the base portion 31. Reaches the chamber 53.

  The first filter chambers 554 and 563 provided in the middle of the first introduction path 55 and the second introduction path 56 are each provided with a filter 57 that removes foreign matters such as dust and bubbles contained in the ink. ing.

  Here, the third introduction channel 553 and the fourth introduction channel 555 communicate with the first filter chamber 554 in the middle of the first introduction channel 55 on both sides of the filter 57 of the first filter chamber 554, respectively. doing. As a result, the ink supplied from the third introduction channel 553 passes through the filter 57 and is supplied to the fourth introduction channel 555.

  Similarly, in the first filter chamber 563 provided in the middle of the second introduction path 56, a sixth introduction flow path 562 and a seventh introduction flow path 564 communicate with both sides of the filter 57. As a result, the ink supplied from the sixth introduction channel 562 passes through the filter 57 and is supplied to the seventh introduction channel 564.

  Incidentally, in the present embodiment, as shown in FIG. 2, seven connection ports 51 are provided, and seven introduction paths 52 are provided corresponding to the seven connection ports 51. Of the seven introduction paths 52, four first introduction paths 55 and three second introduction paths 56 are provided.

  As described above, the first introduction channel 55 configured by the first introduction channel 551 to the fourth introduction channel 555 and the second introduction channel 56 configured by the fifth introduction channel 561 to the seventh introduction channel 564. Are provided, the second introduction flow path 552 and the sixth introduction flow path 552 used for connection from the introduction path 52 in which the ink flows downward in the figure to the introduction path 52 in which the ink flows upward in the figure. The flow path 562 can be disposed at a different position between the first flow path member 41 and the base portion 31 and between the first flow path member 41 and the second flow path member 42. Thereby, since the area which provides the 2nd introduction flow path 552 and the 6th introduction flow path 562 can be narrowed, the back pressure control unit 20 can be reduced in size. Each of these introduction paths 52 communicates with each chamber 53 provided in the pressure chamber forming member 43.

  The chamber 53 has a concave shape that opens to the side opposite to the second flow path member 42 of the pressure chamber forming member 43 that is a plate-like member. The chamber 53 communicates with the introduction path 52 at the bottom surface on the one end side in the longitudinal direction, and communicates with the supply path 54 at the bottom surface on the other end side.

  Such a chamber 53 is sealed by a film member 45 provided on the opening surface of the pressure chamber forming member 43. Here, the film member 45 is a flexible thin film, and is fixed to the surface of the pressure chamber forming member 43 by heat welding or the like. The film member 45 is pressure-molded so as to be bent into a dome shape in the chamber 53.

  Further, an elastic plate 46 disposed on the film member 45 side is provided in the chamber 53 of the pressure chamber forming member 43. The elastic plate 46 is provided so as to protrude into the chamber 53 with one end portion fixed to the surface side of the pressure chamber forming member 43, and the tip thereof is a free end in the chamber 53. In the present embodiment, as shown in FIG. 2, the elastic plate 46 has a common portion 46 a common to the plurality of elastic plates 46 on the fixed end side, and an elastic portion 46 c divided by a slit 46 b protruding into the chamber 53. It had what was called a comb-tooth shape comprised by these.

  Such an elastic plate 46 is fixed by the common portion 46 a being held on the opening surface side of the chamber 53. The elastic plate 46 may be a plate-like member having elasticity and ink resistance. In this embodiment, a stainless plate is used.

  The supply path 54 is provided through the first flow path member 41 in communication with the second filter chamber 541 and the second filter chamber 541 provided through the second flow path member 42 in the thickness direction. The first supply flow path 542 and the second supply flow path 543 provided between the first flow path member 41 and the base portion 31 are provided. That is, the ink from the chamber 53 is supplied to the supply port 314 provided in the base portion 31 via the second filter chamber 541, the first supply channel 542, and the second supply channel 543.

  In addition, the second filter chamber 541 is provided with a filter 57 for removing foreign matters such as dust and bubbles contained in the ink as in the first filter chamber 554 described above. That is, the ink from the chamber 53 passes through the filter 57 and is supplied to the head body 80 via the first supply channel 542 and the second supply channel 543.

  In addition, on the surface of the protective plate 44 on the pressure chamber forming member 43 side, a film holding portion 58 having a concave shape, which is a space that opposes each chamber 53 and allows deformation of the film member 45, is provided.

  Further, the back pressure control unit 20 is provided with an air release path 59 communicating with the outside for releasing the atmosphere of the film holding unit 58 to the atmosphere.

  Here, the atmosphere opening path 59 will be described in detail with reference to FIGS. 2, 4 and 6.

  The air release path 59 is provided on the surface of the protective plate 44 opposite to the pressure chamber forming member 43 and the through hole 591 penetrating in the thickness direction opening on the bottom surface of the film holding portion 58 of the protective plate 44. The first narrow path 592, the second narrow path 593 provided on the same surface as the first narrow path 592 of the protection plate 44 and communicating with the first narrow path 592, and the second narrow path 593 are communicated. A serpentine 594 and an external communication hole 595 (see FIG. 3) provided in the cover portion 32 are provided.

  The first narrow path 592 includes a first groove 592a having a concave shape provided on the surface of the protection plate 44 opposite to the pressure chamber forming member 43 and corresponding to each film holding part 58, and FIG. And a convex portion 592b having a convex shape provided corresponding to the first groove portion 592a of the cover portion 32 shown. The film holding portion 58 and the first narrow path 592 communicate with each other through a through hole 591 provided at one end portion in the longitudinal direction of the chamber 53.

  As shown in FIG. 6, the second narrow path 593 has a concave shape provided between the first groove portions 592 a that define the first narrow path 592. In addition, the opening of the second narrow path 593 on the cover portion 32 side is sealed by the convex portion 592b. Further, the first narrow path 592 and the second narrow path 593 communicate with the through hole 591 at the end opposite to the longitudinal direction. Specifically, as shown in FIG. 4, the convex portion 592 b is provided with an opening 592 c that opens on the side surface of the first narrow path 592 on the side opposite to the through hole 591. Further, the convex portion 592b seals other than both end portions of the second narrow path 593. Accordingly, the first narrow path 592 and the second narrow path 593 communicate with each other on the side opposite to the through hole 591 through the opening 592c.

  Further, the protective plate 44 is provided with a meandering path 594 that is a groove having a meandering concave shape on the opposite side to the opening 592c of the convex portion 592b. The serpentine path 594 has one end communicating with the second narrow path 593 and the other end communicating with an external communication hole 595 provided through the cover portion 32 in the thickness direction. That is, the film holding portion 58 that defines a space on the opposite side of the chamber 53 of the film member 45 includes the through hole 591, the first narrow path 592, the second narrow path 593, the serpentine path 594, and the external communication hole 595. It communicates with the outside through an atmosphere open path 59 comprising In this way, the film holding portion 58 on the opposite side of the film member 45 from the chamber 53 is opened to the atmosphere by the atmosphere opening path 59, so that the film member 45 is deformed by the pressure difference between the pressure inside the chamber 53 and the atmospheric pressure. be able to. Further, the atmosphere opening path 59 is configured by the through hole 591, the first narrow path 592, the second narrow path 593, the serpentine path 594, and the external communication hole 595, so that the atmosphere opening path 59 has a narrow cross-sectional area. Can be formed longer. Thereby, diffusion resistance can be imparted to the atmosphere opening path 59 and moisture evaporation from the film member 45 can be suppressed. Incidentally, the moisture of the ink filled in the chamber 53 permeates through the film member 45. Therefore, if an air opening path that does not impart diffusion resistance is provided, the moisture of the ink that has permeated through the film member 45 is likely to evaporate. Problems such as an increase in ink viscosity occur. In the present embodiment, the evaporation of moisture in the ink that passes through the film member 45 can be suppressed, so that it is possible to suppress the occurrence of problems such as an increase in the viscosity of the ink.

  Further, the cover portion 32 is provided with a first seal portion 34, a second seal portion 35, and a third seal portion 36 made of rubber, elastomer, or the like in a state of being separated from each other.

  As described above, the first seal portion 34 is provided over the distal end surface of the second wall portion 322 of the cover portion 32, and the seam of the outer periphery between the base portion 31 and the cover portion 32 is formed by the first seal portion 34. Sealing is performed to prevent the ink in the holding portion 33 of the cover 30 from flowing out.

  The second seal part 35 is provided at a position opposite to the meandering path 594 of the cover part 32 and seals the opening of the meandering path 594 on the cover part 32 side. The second seal portion 35 is provided with a communication hole 35a that communicates with the external communication hole 595 of the atmosphere opening passage 59, and the second seal portion 35 is actually other than the communication hole 35a of the meander passage 594. The region is sealed.

  The third seal portion 36 is provided over the periphery of the opening 323 on the surface of the protrusion 324 provided with the opening 323 described above on the protective plate 44 side. The third seal portion 36 is for sealing a gap with the cover portion 32 around the connection port 51 of the flow path member 40. By fixing to the opening 323 by the third seal portion 36, it is possible to prevent ink leaking when the supply pipe connected to the connection port 51 is attached or detached from flowing into the holding portion 33. At the same time, the ink in the holding part 33 can be prevented from leaking from the gap with the cover part 32 around the connection port 51.

  The first seal portion 34, the second seal portion 35, and the third seal portion 36 are provided on the cover portion 32 at different heights. Specifically, the first seal portion 34 is provided on the distal end surface of the second wall portion 322 of the cover portion 32 as described above. Further, the second seal portion 35 is provided on the bottom surface (the surface opposite to the protection plate 44) of the second holding portion 321 of the cover portion 32. Further, the third seal portion 36 is provided on the distal end surface of the protruding portion 324 that protrudes lower than the second wall portion 322 of the cover portion 32. Therefore, the first seal portion 34, the second seal portion 35, and the third seal portion 36 are provided at positions where the height of the cover portion 32 is different. Here, the height of the cover portion 32 refers to the thickness direction in the stacking direction of the base portion 31 and the cover portion 32. Therefore, the first seal part 34, the second seal part 35, and the third seal part 36 are provided at different positions in the stacking direction of the cover part 32.

  In addition, the height of the second wall portion 322 of the cover portion 32 is set to the same height as the bottom surface of the cover portion 32 provided with the second seal portion 35 and the projection portion 324 provided with the third seal portion 36. It is difficult. For example, if the height of the second wall portion 322 is the same as the bottom surface of the cover portion 32 provided with the second seal portion 35, the second holding portion 321 can be sufficiently secured. It is not possible. Further, in order to secure the holding portion 33, even if the first wall portion 315 defining the first holding portion 311 of the base portion 31 is raised, the screw member inserted from the bottom surface (head body side) of the base portion 31. This is because an area for screwing (not shown) into the cover portion 32 becomes insufficient, and it becomes difficult to securely fix the base portion 31 and the cover portion 32. Further, for example, if the height of the second wall portion 322 is set to the same height as the protrusion 324 provided with the third seal portion 36, the third seal portion 36 and the second seal portion 35 are close to each other. Ink leaked from the connection port 51 is likely to leak to the outside through the third seal portion 36 and the second seal portion 35. If the height of the protrusion 324 is the same as that of the second wall 322, the position of the connection port 51 must be changed on the flow channel member 40 side, and the connection port 51 of the flow channel member 40 is provided. Therefore, there is a problem that the area is increased and the size is increased.

  In the present embodiment, by providing the first seal portion 34, the second seal portion 35, and the third seal portion 36 at positions where the height of the cover portion 32 is different, the second holding portion 321 is sufficiently secured, The base portion 31 and the cover portion 32 can be firmly fixed, and the first seal portion 34 and the third seal portion 36 are separated from each other to make it difficult for the ink in the holding portion 33 to leak to the outside. Can do. In addition, since the first seal portion 34, the second seal portion 35, and the third seal portion 36 can be provided at positions where the height of the cover portion 32 is different, the boundary of the cover 30 of the back pressure control unit 20, the connection port 51 In addition, the position of the serpentine 594 can be provided at different heights, so that the degree of freedom in design is high and downsizing is possible.

  The first seal portion 34, the second seal portion 35, and the third seal portion 36 are integrally formed with the cover portion 32 by two-color molding. In this embodiment, after forming the cover part 32 by shape | molding a resin material, both were integrally formed by shape | molding a rubber material in the predetermined position of the cover part 32. FIG.

  Thus, the cover part 32, the 1st seal part 34, the 2nd seal part 35, and the 3rd seal part 36 are integrally formed by two-color molding, so that the first seal part 34 and the second seal part are formed. The positioning of the 35 and the third seal portion 36 is not necessary, and the assembling work of the back pressure control unit 20 can be simplified and the cost can be reduced. In particular, as in the present embodiment, when the first seal portion 34, the second seal portion 35, and the third seal portion 36 are provided at positions where the height of the cover portion 32 is different, positioning work is not required and assembly is performed. The operation can be simplified, and the occurrence of ink leakage due to the displacement of the first seal portion 34, the second seal portion 35, and the third seal portion 36 can be suppressed.

  Further, when the plate-like seal member which is a separate body is used by integrally forming the cover portion 32, the first seal portion 34, the second seal portion 35, and the third seal portion 36 by two-color molding. Compared to the above, the number of parts can be reduced, and the manufacturing cost and assembly cost can be reduced.

  Further, as shown in FIG. 3, a valve body 100 is provided between the introduction path 52 and the chamber 53 to open and close the communication state between them.

  Specifically, on the bottom surface of the pressure chamber forming member 43, a cylindrical case portion 101 extending vertically is formed in the introduction path 52 (the fourth introduction flow path 555 and the seventh introduction flow path 564). The lower surface of the case portion 101 is in contact with the bottom surfaces of the fourth introduction channel 555 and the seventh introduction channel 564. The inside of the case portion 101 communicates with the chamber 53, and a slit 102 that communicates the inside and outside of the case portion 101 is provided on the side surface of the case portion 101. Thereby, the chamber 53 and the introduction path 52 communicate with each other through the inside of the case portion 101.

  A valve body 100 is provided in the case portion 101. The valve body 100 includes a cylindrical shaft portion 104 that is inserted into an insertion hole 103 that allows the inside of the case portion 101 and the chamber 53 to communicate with each other, and a shaft portion that is provided at the lower end of the shaft portion 104 in the case portion 101. And a disc-shaped flange 105 having an outer diameter larger than the outer diameter of 104. The lower end of the shaft portion 104 is connected to the center of the upper surface of the flange portion 105, and the upper end of the shaft portion 104 is in contact with the lower surface (surface on the chamber 53 side) of the elastic plate 46.

  The outer diameter of the flange portion 105 is larger than the inner diameter of the insertion hole 103 and slightly smaller than the inner diameter of the case portion 101. In addition, a coil spring 106, which is an example of an urging member, is disposed between the lower surface of the flange portion 105 (the surface on the second flow path member 42 side) and the bottom surfaces of the fourth introduction flow path 555 and the seventh introduction flow path 564. It is intervened.

  The coil spring 106 biases the valve body 100 upward (in the film member 45 side), which is the direction in which the valve body 100 is always closed. When the valve body 100 is in the closed state, the flange portion 105 is in close contact with the upper wall surface in the case portion 101 and the insertion hole 103 is closed, that is, the inside of the case portion 101 and the introduction path 52 communicate with each other. There is no out of communication.

  When the inside of the chamber 53 becomes negative pressure due to the supply of ink to the head main body 80, the film member 45 is moved to the chamber 53 side (second flow path member 42 side) due to the differential pressure from the atmospheric pressure inside the film holding portion 58. Displace to bend. As the film member 45 is displaced, the elastic portion 46c of the elastic plate 46 is elastically deformed so as to bend toward the second flow path member 42 side.

  Due to the elastic deformation of the elastic plate 46, the shaft portion 104 depresses the valve body 100 toward the second flow path member 42 against the urging force of the coil spring 106, so that the wall portion 105 opens the insertion hole 103. The chamber 53 and the introduction path 52 communicate with each other.

  As described above, when the chamber 53 and the introduction path 52 communicate with each other, the ink in the introduction path 52 flows into the chamber 53. When the ink in the chamber 53 and the supply path 54 is sufficiently filled, the negative pressure in the chamber 53 is eliminated, the elastic plate 46 returns to its original state, and each valve is driven by the biasing force of each coil spring 106. When the body 100 is closed, the inside of each chamber 53 is always maintained at a constant pressure.

  On the bottom surface of the base portion 31 of the back pressure control unit 20, a head case 70 that holds the circuit board 60 with the base portion 31 and a head body 80 provided on the bottom surface of the head case 70 are provided. It has.

  The head case 70 has substantially the same area as the base portion 31, is fixed to the bottom surface of the base portion 31, and holds the circuit board 60 with the base portion 31.

  The circuit board 60 is arranged so that a connector to which external wiring is connected faces upward in a region opposite to the wiring insertion hole 312. As such a circuit board 60, one that is commonly connected to the plurality of head main bodies 80 can be used.

  Although not particularly shown, the head main body 80 is provided with two or more rows in which nozzle openings are arranged in parallel, and is provided so that various inks supplied from each back pressure control unit 20 can be discharged from each nozzle row. . In this embodiment, although not particularly shown, four head main bodies are provided so that two color inks are ejected from the three head main bodies, and two inks of one color are ejected from one head main body. It was made to discharge from the nozzle row. As a result, seven colors of ink can be ejected. The number of head main bodies 80 is not particularly limited in arrangement, and for example, the same number of head main bodies 80 as the supply paths 54 may be provided.

  The head body 80 is provided with a pressure generating chamber communicating with the nozzle opening and a pressure generating means for causing a pressure change in the pressure generating chamber, although not particularly shown. As such pressure generating means, for example, a pressure change chamber is generated by changing the volume of the pressure generating chamber by deformation of a piezoelectric actuator having a piezoelectric material exhibiting an electromechanical conversion function, and an ink droplet is ejected from a nozzle opening. A heat generating element is placed in the pressure generating chamber, and ink droplets are ejected from the nozzle opening by bubbles generated by the heat generated by the heat generating element, or static electricity is generated between the diaphragm and the electrode and vibrated by electrostatic force. A so-called electrostatic actuator that deforms the plate and ejects ink droplets from the nozzle openings can be used.

(Other embodiments)
As mentioned above, although one Embodiment of this invention was described, the basic composition of this invention is not limited to what was mentioned above. For example, in Embodiment 1 described above, the first seal portion 34, the second seal portion 35, and the third seal portion 36 are integrally formed on the cover portion 32 side by two-color molding. Instead, for example, the first seal portion 34 may be integrally formed on the first wall portion 315 side of the base portion 31 by two-color molding. Similarly, the third seal portion 36 may be integrally formed around the connection port 51 of the second flow path member 42.

  These ink jet recording heads 10 are mounted on an ink jet recording apparatus. FIG. 7 is a schematic perspective view showing an example of the ink jet recording apparatus. As shown in FIG. 7, in the ink jet recording apparatus 1 of the present embodiment, an ink jet recording head 10 is mounted on a carriage 2. The carriage 2 on which the ink jet recording head 10 is mounted is provided on a carriage shaft 2 a attached to the apparatus body 7 so as to be movable in the axial direction.

  In addition, the apparatus main body 7 is provided with a storage unit 3 including a tank in which ink is stored, and the ink from the storage unit 3 is stored in the ink jet recording head 10 (back pressure control unit 20) mounted on the carriage 2. ) Through the supply pipe 4.

  The driving force of the driving motor 8 is transmitted to the carriage 2 via a plurality of gears and timing belt 8a (not shown), so that the carriage 2 on which the ink jet recording head 10 is mounted is moved along the carriage shaft 2a. . On the other hand, the apparatus body 7 is provided with a platen 9 along the carriage shaft 2a, and a recording sheet S, which is a recording medium such as paper fed by a not-shown paper feed roller, is wound around the platen 9. It is designed to be transported.

  In such an ink jet recording apparatus 1, the carriage 2 is moved along the carriage shaft 2 a and ink is ejected by the head body 80 of the ink jet recording head 10 to print on the recording sheet S.

  Further, in the ink jet recording apparatus 1 described above, the ink jet recording head 10 is mounted on the carriage 2 and moves in the main scanning direction. However, the present invention is not particularly limited thereto. The present invention can also be applied to a so-called line-type recording apparatus that is fixed to the apparatus body 7 and performs printing only by moving a recording sheet S such as paper in the sub-scanning direction.

  In the above-described example, the ink jet recording head 10 is described as an example of the liquid ejecting head and the ink jet recording apparatus 1 is illustrated as an example of the liquid ejecting apparatus. The present invention is intended for the entire apparatus, and can of course be applied to a liquid ejecting head and a liquid ejecting apparatus that eject liquid other than ink. Other liquid ejecting heads include, for example, various recording heads used in image recording apparatuses such as printers, color material ejecting heads used in the manufacture of color filters such as liquid crystal displays, organic EL displays, and FEDs (field emission displays). Examples thereof include an electrode material ejection head used for electrode formation, a bio-organic matter ejection head used for biochip production, and the like, and can also be applied to a liquid ejection apparatus provided with such a liquid ejection head.

  DESCRIPTION OF SYMBOLS 1 Inkjet recording device (liquid ejecting apparatus), 10 Inkjet recording head (liquid ejecting head), 20 Back pressure control unit, 30 Cover, 31 Base part, 32 Cover part, 40 Channel member, 41 1st channel member 42 Second flow path member, 43 Pressure chamber forming member, 44 Protection plate, 45 Film member, 46 Elastic plate, 50 Liquid flow path, 51 Connection port, 52 Introduction path, 53 Chamber, 54 Supply path, 59 Air release path , 60 circuit board, 70 case head, 80 head body, 100 valve body, 594 serpentine

Claims (4)

A head body for ejecting liquid;
A back pressure control unit to which the head body is fixed,
The back pressure control unit includes a cover that can be divided on the outer periphery, and a flow path member that is held by a holding portion inside the cover,
The cover includes a base portion and a cover portion fixed to the base portion, and the base portion and the cover portion are fixed in contact with each other on the outer peripheral side,
The channel member includes a grooved serpentine opening to the cover side, a connection port to which an external supply pipe is connected, and a liquid flow that communicates with the connection port and supplies liquid to the head body. Road,
The cover part is provided in a region in contact with the base part of the outer peripheral edge part, a first seal part for sealing the holding part, and a second seal for sealing the opening on the cover part side of the meandering path. A seal portion and a third seal portion that seals a gap between the periphery of the connection port and the cover portion are arranged separately, and the cover portion, the first seal portion, and the second seal portion And the third seal portion is formed by two-color molding.   2. The liquid ejecting head according to claim 1, wherein the first seal portion, the second seal portion, and the third seal portion are provided at different positions in the cover portion.   The liquid jet head according to claim 1, wherein the flow path member is configured by laminating a plurality of plate-like members.   A liquid ejecting apparatus comprising the liquid ejecting head according to claim 1.

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