JP2017136773A - Inkjet head and inkjet device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inkjet head which inhibits hindrance of ink flow from a pressure chamber to a communication passage even when slight misalignment occurs between a structure and an actuator when the structure having the communication passage is adhered to the actuator, and to provide an inkjet device.SOLUTION: An inkjet head includes: a pressure chamber 52 which is filled with an ink; an actuator 30; a nozzle 41 which discharges the ink filling the pressure chamber 52; and a communication passage 54 which connects the pressure chamber 52 with the nozzle 41. A structure 40 having the communication passage 54 is adhered to the actuator 30 to cause the pressure chamber 52 and the communication passage 54 to be connected with each other. In the communication passage 54, a pressure chamber 52 side end part is wider than the other portion.SELECTED DRAWING: Figure 3

Description

  The present invention relates to an inkjet head that ejects ink onto a printing surface and an inkjet apparatus that uses the inkjet head.

  An inkjet apparatus is an apparatus that performs printing or drawing on a printing surface by ejecting ink from an inkjet head. An ink jet head mounted on an ink jet apparatus applies pressure to a pressure chamber for filling ink, a flow path for guiding ink to the pressure chamber, a nozzle connected to the pressure chamber, and ink filled in the pressure chamber. Actuator. By driving the actuator to increase the pressure in the pressure chamber, ink filled in the pressure chamber is ejected from the nozzle.

JP 2005-244174 A

  In the ink jet head having the above-described configuration, the pressure chamber and the nozzle are connected by a communication channel for supplying ink from the pressure chamber to the nozzle. Specifically, the pressure chamber and the communication channel are connected by bonding a structure having a communication channel to the actuator. In this case, when a positional shift occurs between the structure and the actuator when the structure is bonded to the actuator, the area of the communication channel that overlaps the pressure chamber decreases. For this reason, it becomes difficult for ink to flow from the pressure chamber to the communication flow path, and even if an expected driving force is generated in the actuator, a predetermined amount of ink cannot be ejected from the nozzle.

  In view of such a problem, the present invention suppresses ink from being difficult to flow from the pressure chamber to the communication flow path even when a slight displacement occurs between the structure and the actuator when the structure is bonded to the actuator. It is an object of the present invention to provide an ink jet head and an ink jet apparatus that can be used.

  A first aspect of the present invention relates to an inkjet head. An ink jet head according to a first aspect includes a pressure chamber filled with ink, an actuator that changes a pressure of ink filled in the pressure chamber, and the pressure chamber filled when the actuator is driven. A nozzle that discharges the ink; and a communication channel that connects the pressure chamber and the nozzle. The pressure chamber and the communication channel are connected by bonding a structure having the communication channel to the actuator. The communication channel has a wider end on the pressure chamber side than other portions.

  According to the ink jet head according to this aspect, since the end of the communication channel on the pressure chamber side is wider than the other part of the communication channel, the structure and the actuator are bonded when the structure is bonded to the actuator. Even if a slight displacement occurs between the two, the area of the communication channel overlapping the pressure chamber can be suppressed from being significantly reduced. Therefore, it is possible to prevent ink from being difficult to flow from the pressure chamber to the communication channel, and a predetermined amount of ink can be smoothly ejected from the nozzle.

  A second aspect of the present invention relates to an ink jet apparatus. An ink jet apparatus according to a second aspect includes the ink jet head according to the first aspect, and an ink supply unit that supplies ink to the ink jet head.

  According to the ink jet apparatus according to the second aspect, since the ink jet head according to the first aspect is used, a predetermined amount of ink can be smoothly ejected from the nozzle. For this reason, the performance of an inkjet apparatus can be improved.

  As described above, according to the ink jet head and the ink jet device of the present invention, even when a slight displacement occurs between the structure and the actuator when the structure having the communication channel is bonded to the actuator, the pressure chamber Therefore, it is possible to prevent the ink from easily flowing into the communication channel, and thereby a predetermined amount of ink can be smoothly ejected from the nozzle.

  The effects and significance of the present invention will become more apparent from the following description of embodiments. However, the embodiment described below is merely an example when the present invention is implemented, and the present invention is not limited to what is described in the following embodiment.

FIG. 1A is a diagram illustrating a configuration of an ink jet head according to the embodiment, and FIG. 1B is a diagram schematically illustrating a configuration in which the actuator according to the embodiment and a structure are combined. FIG. 2A is an enlarged view of a part of the actuator and the structure according to the embodiment, and FIG. 2B is a diagram schematically showing the main flow path and the pressure chamber. FIG. 2C is a diagram schematically showing the arrangement of nozzles in the structure. FIG. 3 is a partial perspective view showing a configuration in the vicinity of the pressure chamber according to the embodiment. FIGS. 4A and 4B are diagrams schematically showing the overlap between the pressure chamber according to the comparative example and the inlet of the communication channel. FIGS. 5A and 5B are diagrams schematically showing the overlap between the pressure chamber and the inlet of the communication channel according to the embodiment, respectively. FIG. 6 is a block diagram illustrating a configuration of the ink jet apparatus according to the embodiment. FIGS. 7A and 7B are diagrams schematically showing the overlap between the pressure chamber and the inlet of the communication channel according to the modified example, respectively. FIGS. 8A and 8B are diagrams schematically illustrating an overlap between a pressure chamber and an inlet of a communication channel according to another modification.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. For convenience, the X, Y, and Z axes that are orthogonal to each other are appended to each drawing. The Z-axis direction is the height direction of the inkjet head 1, and the positive Z-axis direction is the downward direction. Further, the X-axis direction is the thickness direction of the inkjet head 1, and the Y-axis direction is the width direction of the inkjet head 1. The inkjet head 1 ejects ink in the positive Z-axis direction (downward). The X-axis direction corresponds to a “first direction” according to claim 2, and the Y-axis direction corresponds to a “second direction” according to claim 2.

  Fig.1 (a) is a figure which shows the structure of the inkjet head 1 which concerns on embodiment, FIG.1 (b) shows typically the structure which combined the actuator 30 and structure 40 which concern on embodiment. FIG.

  As shown in FIG. 1A, the inkjet head 1 includes a storage box 10 and a head base 20. The storage box 10 is detachable from the head base 20.

  The storage box 10 is a rectangular box whose bottom surface is open. A cutout 10a connected to the inside is provided on the upper surface of the storage box 10, and the circuit board 11 is stored in the storage box 10 through the cutout 10a. A drive circuit for driving the actuator 30 is mounted on the circuit board 11. Circular holes 10b are respectively provided on the Y axis positive side and the Y axis negative side of the notch 10a. The hole 10 b is for guiding an ink supply tube (not shown) to the inside of the storage box 10.

  The head base 20 is composed of a frame having a rectangular opening 20a penetrating vertically. The actuator 30 and the structure 40 shown in FIG. 1B are installed at the lower end of the opening 20a. The actuator 30 is electrically connected to the circuit board 11 by FPC (Flexible Printed Circuits) in the opening 20a.

  As shown in FIG.1 (b), the actuator 30 consists of a plate body which has a rectangular outline. The actuator 30 is overlaid on the upper surface of the structure 40. The structure 40 is a plate having a rectangular outline. In the structure 40, four main flow paths 51 arranged in the X-axis direction are formed.

  Four ink supply ports 30a are formed side by side in the X-axis direction at the Y-axis positive end and the Y-axis negative end of the actuator 30, respectively. Each of the two ink supply ports 30a arranged in the Y-axis direction is connected to one independent main channel 51.

  Fig.2 (a) is the figure which expanded the edge part by the side of the Y-axis positive side of the structure of FIG.1 (b).

  A groove is formed on the back surface of the actuator 30. By overlapping the actuator 30 on the structure 40, a pressure chamber 52 is formed between the groove on the back surface of the actuator 30 and the upper surface of the structure 40. The pressure chamber 52 is connected to the main flow path 51 via a communication flow path 53 (see FIG. 2B) formed in the structure 40.

  Note that a terminal group (not shown) for connecting the FPC of the circuit board 11 is provided on each of the X-axis negative side end and the X-axis positive side end of the upper surface of the actuator 30. This terminal group is for applying a voltage (drive signal) to the piezoelectric layer 34 (see FIG. 2B) of the actuator 30.

  As described above, the end of the main channel 51 is connected to the ink supply port 30a. A large number of pressure chambers 52 are arranged along the main flow path 51, and each pressure chamber 52 is connected to the main flow path 51 by each communication flow path 53.

  Referring back to FIG. 1B, tubes (not shown) are individually fitted into the eight ink supply ports 30a, and ink is supplied to the tubes from ink supply tubes (not shown). . The tube is supported by a support member disposed in the opening 20a, and a tube for supplying ink to the tube is drawn out through the hole 10b. Ink is supplied to the ink supply port 30a through the ink supply tube and the tube. As a result, ink is supplied to the pressure chamber 52 through the main channel 51 and the communication channel 53.

  The same color ink is supplied to the two ink supply ports 30a arranged in the Y-axis direction, and different color inks are supplied to the four ink supply ports 30a arranged in the X-axis direction. Therefore, in the configuration shown in FIG. 1B, four colors of ink are supplied to the actuator 30. As a result, the pressure chambers 52 arranged in the Y-axis direction are filled with the same color ink, and the pressure chambers 52 arranged in the X-axis direction are filled with inks of different colors. A combination of the actuator 30 and the structure 40 is installed at the lower end of the opening 20 a of the head base 20. Therefore, four colors of ink are ejected from the lower surface of the head base 20.

  2B, the pressure chamber 52 in the vicinity of the X-axis positive side (right side) of FIG. 2A is cut along a plane parallel to the XZ plane at the center position in the Y-axis direction of the pressure chamber 52. It is sectional drawing which shows a cross section typically.

  The ink 60 that has flowed into the main channel 51 passes through the communication channel 53 and fills the pressure chamber 52. The structure 40 includes an upper member 40 a having a main channel 51 and communication channels 53 and 54 and a lower member 40 b having a nozzle 41. In the lower member 40b, a substantially circular hole serving as the nozzle 41 is formed in a portion of the communication channel 54 extending from the pressure chamber 52 in the positive Z-axis direction. The nozzle 41 gradually decreases in diameter toward the positive direction of the Z axis, and the diameter is uniform in the vicinity of the outlet.

  The actuator 30 is configured by laminating a diaphragm layer 32, an insulating layer 33, a piezoelectric layer 34, and an electrode layer 35 on the pressure chamber layer 31. The diaphragm layer 32, the insulating layer 33, the piezoelectric layer 34, and the electrode layer 35 are formed by a vacuum film forming technique such as sputtering. These layers may be formed by other film forming techniques such as coating. The pressure chamber layer 31 is formed by a thick film forming technique such as a plating method or a metal plate etching method. By attaching the upper member 40 a to the lower surface of the pressure chamber layer 31, the pressure chamber 52 is formed. The diaphragm layer 32 is made of a conductive metal material and also serves as a lower electrode (common electrode) of the piezoelectric layer 34. The insulating layer 33 insulates the diaphragm layer 32 from the piezoelectric layer 34. That is, the insulating layer 33 shields voltage application to the piezoelectric layer 34 other than the piezoelectric functional region R1.

  The piezoelectric layer 34 is made of, for example, lead zirconate titanate (PZT). The film thickness of the piezoelectric layer 34 is about several μm. The electrode layer 35 is formed of a conductive material. The electrode layer 35 is formed from titanium containing a noble metal, for example. The film thickness of the electrode layer 35 is about 0.2 μm.

  When a voltage is applied to the electrode layer 35, the piezoelectric layer 34 is deformed in the Z-axis direction in the piezoelectric functional region R1, and accordingly, the diaphragm layer 32 is deformed. When the diaphragm layer 32 is deformed downward in the piezoelectric function region R1, the volume of the pressure chamber 52 is reduced, and the pressure of the ink 60 filled in the pressure chamber 52 is increased. Thereby, the droplet 61 of the ink 60 is ejected from the nozzle 41.

  Each of the pressure chamber layer 31, the diaphragm layer 32, the insulating layer 33, the piezoelectric layer 34, and the electrode layer 35 is not necessarily a single layer, and may be formed of a plurality of layers. Further, another layer may be disposed between the layers.

  FIG. 2C is a diagram schematically showing the arrangement of the nozzles 41 in the structure 40.

  As shown in FIG. 2C, the structure 40 has a plurality of nozzles 41 arranged in a line. In the structure 40, rows L1 to L4 of four nozzles 41 are arranged. For example, 200 nozzles 41 are provided at regular intervals in each of the rows L1 to L4. The number of nozzles 41 in each row is not limited to this.

  FIG. 3 is a partial perspective view showing a cross section of the configuration in the vicinity of the pressure chamber 52.

  As shown in FIG. 3, the upper member 40 a of the structure 40 is configured by stacking plate-like bodies 411 and 412, seven plate-like bodies 413, and a plate-like body 414. Each of the plate-like bodies 411 to 414 has a predetermined thickness, and has the same contour as that of the structure body 40 in plan view. The seven plate-like bodies 413 have the same structure. A thin damper 415 is sandwiched between the first and second plate-like bodies 413 from the bottom. The damper 415 is for absorbing a pressure wave applied from the communication channel 53 to the main channel 51 when the actuator 30 is driven and the diaphragm layer 32 is displaced downward (Z-axis positive direction). is there.

  In the plate-like bodies 411 and 412, long holes 411 a and 412 a for forming the communication channel 54 are formed, respectively. In the long holes 411a and 412a, the X-axis direction is the longitudinal direction. In plan view, each of the long holes 411a and 412a has an oval outline that is long in the X-axis direction. More specifically, the long hole 411a has an outline in which the ends of two semicircular arcs facing each other are connected by a straight line. The long hole 412a has an outline in which two semicircular arcs similar to the long hole 411a are connected by a straight line shorter than the long hole 411a.

  The seven plate-like bodies 413 are formed with holes 413 a for forming the communication channel 54. The hole 413a is substantially circular. The plate-like body 414 and the damper 415 are also formed with holes 414a and 415a for forming the communication channel 54, respectively. The diameters of the holes 414a and 415a are substantially the same as the diameter of the hole 413a. The seven holes 413a have the same center. The centers of the holes 414a and 415a coincide with the center of the hole 413a. The center of the nozzle 41 coincides with the center of the holes 413a, 414a, 415a.

  The center of the long hole 412a coincides with the center of the hole 413a in the Y-axis direction, and deviates in the X-axis negative direction from the center of the hole 413a in the X-axis direction. Further, the center of the long hole 411a coincides with the center of the long hole 412a in the Y-axis direction, and is shifted from the center of the long hole 412a in the X-axis negative direction in the X-axis direction. In plan view, the X-axis positive side edge of each of the long holes 411a and 412a coincides with the X-axis positive side edge of the hole 413a.

  In the plate-like bodies 412, 413, openings 412b, 413b are formed in regions corresponding to the main flow paths 51, respectively. The opening 412b is narrower in the X-axis direction than the opening 413b. In plan view, the edge on the X axis positive side of the opening 412b coincides with the edge on the X axis positive side of the opening 413b. The main flow path 51 is partitioned by a damper 415.

  In the plate-like body 411, an opening 411b is formed in a region corresponding to the communication channel 53, and a filter 411c is formed at the bottom of the opening 411b. The filter 411c has a large number of holes having a diameter of about several μm. The diameter of the hole provided in the filter 411c is slightly smaller than the diameter of the outlet of the nozzle 41. In plan view, the opening 411b has an oval outline that is long in the X-axis direction. More specifically, the opening 411b has a contour in which the ends of two semicircular arcs facing each other are connected by a straight line.

  The long hole 411a, the hole 412a, and the opening 411b described above may have a large circular shape. However, the pitch of the nozzles 41 cannot be reduced and obstructs high-density printing, so that it is necessary to have a long hole shape.

  The opening 411 b is arranged so that the X axis positive side overlaps the pressure chamber 52 and the X axis negative side does not overlap the pressure chamber 52. On the X-axis negative side of the opening 411b, the ink that has passed through the filter 411c from the main flow path 51 passes between the filter 411c and the lower surface of the pressure chamber layer 31, and from the X-axis positive side of the opening 411b to the pressure chamber 52. And enter. When the actuator 30 is driven to increase the pressure in the pressure chamber 52, the ink filled in the pressure chamber 52 passes through the communication channel 54 constituted by the long holes 411a, 412a and the holes 413a, 414a, 415a, and the nozzle 41 It is discharged from.

  As shown in FIG. 3, in this embodiment, the upper member 40a of the structure 40 is configured by stacking a plurality of plate-like bodies 411, 412, 413, 414, and the lower member 40b is formed on the lower surface of the upper member 40a. Bonded or bonded using a thermal diffusion method. Further, the upper member 40 a is bonded to the lower surface of the pressure chamber layer 31, and the structure 40 including the upper member 40 a and the lower member 40 b is attached to the actuator 30. That is, the pressure chamber 52 and the communication channel 54 are connected by bonding the structure 40 having the communication channel 54 to the actuator 30. At the same time, the pressure chamber 52 and the communication channel 53 are connected.

  In this configuration, the diameter of the communication channel 54 is usually constant in the entire region in the Z-axis direction. In this case, when a positional shift occurs between the structure 40 and the actuator 30 when the structure 40 is bonded to the actuator 30, the area of the communication channel 54 that overlaps the pressure chamber 52 decreases from the normal area. . For this reason, it becomes difficult for ink to flow from the pressure chamber 52 to the communication flow path 54, and even if the desired driving force is generated in the actuator 30, a predetermined amount of ink cannot be ejected from the nozzle 41.

  In order to solve this problem, in the present embodiment, long holes 411a and 412a are formed in the first plate-like body 411 and the plate-like body 412 below it from the pressure chamber 52 side, and the other plate-like bodies 413 are formed. 414 is wider than the holes 413a and 414a in the X-axis direction. As a result, even when a slight displacement occurs between the structure 40 and the actuator 30 when the structure 40 is bonded to the actuator 30, the area of the communication channel 54 that overlaps the pressure chamber 52 is significantly reduced. Can be suppressed.

  Hereinafter, this effect will be described with reference to FIGS. 4 (a) and 4 (b) and FIGS. 5 (a) and 5 (b).

  4A and 4B are diagrams schematically showing the overlap between the pressure chamber 52 and the inlet of the communication channel 54 according to the comparative example, respectively. 4A and 4B show a state in which the pressure chamber 52 is seen through from the Z-axis positive side. For convenience, FIGS. 4A and 4B show the overlap between the three pressure chambers 52 and the inlets of the communication channel 54.

  Unlike the above-described embodiment, in the comparative example, the end of the communication channel 54 on the pressure chamber 52 side is not expanded in the X-axis direction. That is, the long hole 411a formed in the uppermost plate-like body 411 shown in FIG. 3 is replaced with a circular hole 411a ′ having the same diameter as the hole 413a formed in the plate-like body 413. The center coincides with the center of the hole 413a. Similarly, the long hole 412a formed in the second plate-like body 412 shown in FIG. 3 is replaced with a circular hole having the same diameter as the hole 413a formed in the plate-like body 413. The center coincides with the center of the hole 413a. The diameter of the hole 411 a ′ is slightly larger than the width of the pressure chamber 52 in the Y-axis direction.

  In the configuration of the comparative example, when the structure 40 is bonded to the actuator 30 without misalignment as shown in FIG. 4A, the area S1 of the communication channel 54 that overlaps the pressure chamber 52 is appropriately secured. .

  However, in the configuration of the comparative example, as illustrated in FIG. 4B, when a positional shift in the Y-axis direction occurs between the structure 40 and the actuator 30 when the structure 40 is bonded to the actuator 30, the pressure The area S2 of the communication channel 54 that overlaps the chamber 52 decreases from the normal area S1. Similarly, when a positional shift in the X-axis direction occurs between the structure 40 and the actuator 30, the area of the communication channel 54 that overlaps the pressure chamber 52 decreases from the normal area S1. For this reason, it becomes difficult for ink to flow from the pressure chamber 52 to the communication flow path 54, and even if the desired driving force is generated in the actuator 30, a predetermined amount of ink cannot be ejected from the nozzle 41.

  FIGS. 5A and 5B are diagrams schematically showing the overlap between the pressure chamber 52 and the inlet of the communication channel 54 according to the embodiment, respectively. Like FIGS. 4A and 4B, FIGS. 5A and 5B show a state in which the pressure chamber 52 is seen through from the Z-axis positive side. The overlap with the inlet of the communication channel 54 is shown. 5A and 5B, a region where the hole 413a constituting the communication channel 54 and the pressure chamber 52 overlap is surrounded by a broken line, and the long hole 411a and the pressure chamber constituting the communication channel 54 are surrounded. The area where 52 overlaps is hatched.

  In the configuration of the embodiment, when the structure 40 is bonded to the actuator 30 without misalignment as shown in FIG. 5A, the area of the communication channel 54 that overlaps the pressure chamber 52 is ensured appropriately. . Here, the area S1 where the holes 413a, 414a, and 415a continuing to the nozzle 41 shown in FIG. 3 overlap the pressure chamber 52 is the same as the area S1 of the comparative example shown in FIG. However, in the embodiment, since the first and second elongated holes 411a and 412a from the pressure chamber 52 side are expanded in the X-axis direction as compared with the hole 413a, the area S3 where the elongated hole 411a overlaps the pressure chamber 52 is provided. Is larger than the area S1 of the comparative example shown in FIG. That is, the area where the inlet of the communication channel 54 overlaps the pressure chamber 52 is larger than the area S1 of the comparative example shown in FIG.

  For this reason, in the configuration of the embodiment, as shown in FIG. 5B, when the structure 40 is bonded to the actuator 30, a positional shift in the Y-axis direction occurs between the structure 40 and the actuator 30. In this case, the area S2 where the main flow portion of the communication channel 54 overlaps the pressure chamber 52 decreases from the normal area S1, but the area where the inlet of the communication channel 54 overlaps the pressure chamber 52, that is, the long hole 411a is the pressure chamber. An area S4 overlapping 52 is secured widely. For this reason, the ink is smoothly guided from the inlet of the communication channel 54 to the main flow portion of the communication channel 54, and the ink flow is ensured even when a positional deviation occurs as compared with the comparative example. This effect can be similarly achieved even when a positional shift in the X-axis direction occurs between the structure 40 and the actuator 30.

  As described above, according to the configuration of the present embodiment, even when a slight positional deviation occurs between the structure 40 and the actuator 30 when the structure 40 is bonded to the actuator 30, the communication flow from the pressure chamber 52 occurs. The ink flow toward the path 54 can be secured. Therefore, even if such a positional deviation occurs, a predetermined amount of ink can be smoothly ejected from the nozzles 41 by causing the actuator 30 to generate a desired driving force.

  FIG. 6 is a block diagram illustrating a configuration of the ink jet apparatus according to the embodiment.

  The ink jet apparatus includes an ink supply unit 2, a controller 3, and an interface 4 in addition to the ink jet head 1 having the above configuration.

  The ink supply unit 2 includes the above-described tube for supplying ink to the inkjet head 1, an ink tank connected to the tube, and a pump for supplying ink from the ink tank to the tube. The controller 3 includes a CPU and a memory, and controls the inkjet head 1 and the ink supply unit 2 in accordance with a program held in the memory. The interface 4 receives input of drawing information such as characters and graphics to be printed and outputs the drawing information to the controller 3.

  The controller 3 controls the inkjet head 1 according to the input drawing information, and performs printing or drawing on the printing surface. In this way, ink is ejected from the nozzle 41 corresponding to the print image onto the printing surface, and printing or drawing is performed on the printing surface.

<Effect of embodiment>
As described above, according to the present embodiment, the following effects are exhibited.

  Since the end of the communication channel 54 on the pressure chamber 52 side is wider than the other part of the communication channel 54, when the structure 40 is bonded to the actuator 30, Even if a slight positional shift occurs, it is possible to suppress a reduction in the area of the communication channel 54 that overlaps the pressure chamber 52. Therefore, it is possible to prevent ink from being difficult to flow from the pressure chamber 52 to the communication channel 54, and a predetermined amount of ink can be smoothly ejected from the nozzle 41.

  As shown in FIG. 3 and FIGS. 5A and 5B, the pressure chamber 52 has a width in the X-axis direction (first direction) that is perpendicular to the X-axis direction (first direction). The width of the communication channel 54 is wider in the X-axis direction (first direction) than the other part. For this reason, the area where the inlet of the communication channel 54 overlaps the pressure chamber 52 can be effectively expanded, and when the positional displacement occurs between the structure 40 and the actuator 30, the inlet of the communication channel 54 is An area overlapping with the pressure chamber 52 can be appropriately secured.

  As shown in FIGS. 3 and 5A and 5B, in the present embodiment, the set of the pressure chamber 52, the communication channel 54, and the nozzle 41 is arranged in the Y-axis direction (second direction). Is arranged. On the other hand, the communication channel 54 has an end on the pressure chamber 52 side in the X-axis direction (first direction) orthogonal to the Y-axis direction (second direction) in which the set of the pressure chamber 52, the communication channel 54 and the nozzle 41 is arranged. In the direction). For this reason, even if the space | interval between the nozzles 41 is narrow, the space | interval of the entrance of the adjacent connection flow path 54 does not become remarkably narrow. For this reason, when the structure 40 is bonded to the actuator 30 while being displaced in the Y-axis direction, the entrance of the communication channel 54 can be prevented from being applied to the adjacent pressure chamber 52.

  As shown in FIG. 3, the communication channel 54 becomes wider as the end portion on the pressure chamber 52 side goes to the pressure chamber 52. For this reason, it is difficult for the ink flow to be inhibited at the inlet portion of the communication channel 54, and the ink can be smoothly guided from the pressure chamber 52 to the main flow portion of the communication channel 54.

  As shown in FIG. 3, in the present embodiment, the structure 40 is configured by stacking a plurality of plate-like bodies 411, 412, 413, and 414. Each plate-like body is formed with long holes 411a, 412a and holes 413a, 414a that constitute a part of the communication channel 54, and the first and second plate-like bodies 411 from the pressure chamber 52 side, The long holes 411a and 412a of 412 are wider than the holes 413a and 414a of the other plate-like bodies 414 and 414. Thus, by making the holes of the plate-like bodies 411 and 412 on the inlet side into the long holes 411a and 412a, the width of the inlet of the communication channel 54 can be easily widened.

  In this case, as shown in FIG. 3, the long holes 411a, 412a of the plate-like bodies 411, 412 from the pressure chamber 52 side to the second are formed so as to become wider toward the pressure chamber 52, and thereby the communication channel 54 becomes wider as the end on the pressure chamber 52 side goes to the pressure chamber 52. As a result, as described above, the ink flow is less likely to be inhibited at the inlet portion of the communication channel 54, and the ink can be smoothly guided from the pressure chamber 52 to the main flow portion of the communication channel 54.

  As shown in FIG. 3, the communication flow path 54 other than the end portion on the pressure chamber 52 side is a hole 413 a, 414 a, 415 a having the same width, and the center thereof coincides with the center of the nozzle 41. In this way, the main flow portion of the communication flow path 54 that continues to the nozzle 41 is made circular in the same manner as the nozzle 41, and the center thereof coincides with the center of the nozzle 41, so that the communication flow path as shown in FIG. Even if the inlet of 54 is widened, the flow of ink toward the nozzle 41 is stabilized. Therefore, ink can be appropriately discharged from the nozzle 41.

<Example of change>
Although the embodiment of the present invention has been described above, the present invention is not limited to the above embodiment.

  For example, in the above embodiment, the width of the inlet of the communication channel 54 is expanded in the X-axis direction (first direction). However, as shown in FIGS. The width of the inlet may be increased in the Y-axis direction (second direction) orthogonal to the X-axis direction (first direction). 7 (a) and 7 (b) show a state in which the pressure chamber 52 is seen through from the Z-axis positive side, as in FIGS. 5 (a) and 5 (b). The overlap with the inlet of the communication channel 54 is shown.

  7A and 7B, only the hole of the plate-like body 411 located closest to the pressure chamber 52 among the holes constituting the communication channel 54 is the long hole 411a, and the pressure chamber Similar to the holes 413a and 414a formed in the third and subsequent plate-like bodies 413 and 414, the hole of the second plate-like body 412 from the 52nd side is a circular hole 412a.

  Also in this modified example, with the positional deviation between the structure 40 and the actuator 30, a positional deviation in the Y-axis direction occurred between the communication channel 54 and the pressure chamber 52 as shown in FIG. 7B. In this case, it is possible to suppress a reduction in the area where the inlet of the communication channel 54 overlaps the pressure chamber 52. Therefore, the effect that the ink flow can be secured with respect to such misalignment can be achieved as in the above embodiment.

  However, in this modified example, since the spreading direction of the long hole 411a is the Y-axis direction, as shown in FIGS. 7A and 7B, the gap between the adjacent long holes 411a becomes considerably narrow. For this reason, when a positional shift in the Y-axis direction occurs between the communication channel 54 and the pressure chamber 52, the pressure chamber 52 is considerably close to the inlet of the adjacent communication channel 54 as shown in FIG. However, there is a concern that the ink filled in the pressure chamber 52 flows into the adjacent communication channel 54. In addition, in this modified example, the spreading direction of the long hole is the Y-axis direction (second direction). Therefore, when the structure 40 and the actuator 30 are displaced in the X-axis direction, FIG. As in the comparative example shown in (b), the area where the inlet of the communication channel 54 overlaps the pressure chamber 52 is significantly reduced.

  On the other hand, in the above-mentioned embodiment, since the spreading direction of the long hole 411a is the X-axis direction (first direction), as shown in FIGS. 5 (a) and 5 (b), between the adjacent long holes 411a. A wide gap can be secured. For this reason, even if a positional shift in the Y-axis direction occurs between the structure 40 and the actuator 30, it is possible to prevent the ink filled in the pressure chamber 52 from flowing into the adjacent communication channel 54. In addition, since the elongating direction of the long hole 411a is the X-axis direction, the inlet of the communication channel 54 is located at the pressure chamber 52 in any direction as compared with the comparative example, regardless of the direction in which the structural body 40 and the actuator 30 are displaced. Wide area can be secured. From these points, it is preferable that the long hole 411a expands in the X-axis direction (first direction) as in the above embodiment.

  With respect to the above-described configuration, the opening 411b formed in the communication passage 53 also has a long hole shape, and thus the same effect can be obtained with respect to the positional deviation from the pressure chamber 52.

  Moreover, in the said embodiment, as shown to Fig.5 (a), (b), the long holes 411a and 412a were made into the elliptical outline, However, The outline of the long holes 411a and 412a is not restricted to this. Absent. For example, as shown in FIGS. 8A and 8B, the outlines of the long holes 411a and 412a may be rectangular or may be other shapes expanded from a circle.

  In the above-described embodiment, the long holes 411a and 412a have a shape that extends from the circular shape only in the X-axis direction (first direction). However, the long holes 411a and 412a have the circular shape and the X-axis direction (first direction). In the Y-axis direction (second direction). However, as described in the modified examples of FIGS. 7A and 7B, in order to prevent the pressure chamber 52 from being placed on the adjacent communication channel 54, a long hole in the Y-axis direction (second direction) is used. It is preferable that the spread of 411a and 412a be kept to a certain extent.

  Moreover, in the said embodiment, as shown in FIG. 3, although the 1st and 2nd hole from the pressure chamber 52 side was made into the long holes 411a and 412a among the holes which comprise the connection flow path 54, a pressure chamber Only the first hole from the 52 side may be a long hole, or the third hole from the pressure chamber 52 side or a predetermined hole thereafter may be a long hole.

  Further, in the above embodiment, the size of the long holes 411a and 412a is constant in the thickness direction (Z-axis direction) of the plate-like bodies 411 and 412, but the size of the long holes 411a and 412a is lower. It may become smaller as it goes in the direction (Z-axis positive direction). In this way, the ink can be more smoothly guided from the pressure chamber 52 to the main flow portion to the communication channel 54.

  Moreover, in the said embodiment, although the upper member 40a of the structure 40 was comprised by overlapping the some plate-shaped body 411, 412, 413, 414, the structure method of the structure 40 is limited to this. It is not something. For example, the upper six plate-like bodies 413 of the seven plate-like bodies 413 shown in FIG. 3 may be integrally formed by one member, or these six plate-like bodies 413 and plate-like bodies 411, 412 May be integrally formed by one member.

  In addition, the configurations of the inkjet head 1 and the actuator 30 and the shapes and configurations of the main flow path 51, the pressure chamber 52, and the communication flow path 53 are not limited to those of the above embodiment. In the above embodiment, ink is supplied from two ink supply ports 30a arranged in the Y-axis direction with respect to one main flow path, but one ink supply port 30a is provided for one main flow path. It may be provided.

  In addition, the embodiment of the present invention can be variously modified as appropriate within the scope of the technical idea shown in the claims.

DESCRIPTION OF SYMBOLS 1 ... Inkjet head 2 ... Ink supply part 30 ... Actuator 40 ... Structure 41 ... Nozzle 53, 54 ... Communication flow path 411, 412, 413, 414 ... Plate-like body 411a, 412a ... Long hole (hole)
411b ... opening 413a, 414a ... hole

Claims (8)

A pressure chamber filled with ink;
An actuator for changing the pressure of the ink filled in the pressure chamber;
A nozzle that ejects the ink filled in the pressure chamber when the actuator is driven;
A communication flow path connecting the pressure chamber and the nozzle,
The pressure chamber and the communication channel are connected by bonding the structure having the communication channel to the actuator,
The communication channel has an end on the pressure chamber side that is wider than other parts.
An inkjet head characterized by that. The inkjet head according to claim 1,
The pressure chamber has a width in a first direction wider than a width in a second direction orthogonal to the first direction,
In the communication channel, the end portion on the pressure chamber side is wider in the first direction than other portions.
An inkjet head characterized by that. The inkjet head according to claim 2,
The set of the pressure chamber, the communication channel, and the nozzle is arranged so as to be aligned in the second direction.
An inkjet head characterized by that. The inkjet head according to any one of claims 1 to 3,
The communication channel becomes wider as the end on the pressure chamber side goes to the pressure chamber.
An inkjet head characterized by that. The inkjet head according to any one of claims 1 to 4,
The structure is configured by stacking a plurality of plate-like bodies,
Each plate-like body is formed with a hole constituting a part of the communication channel,
The hole of at least the first plate-like body from the pressure chamber side is wider than the holes of the other plate-like bodies,
An inkjet head characterized by that. In the inkjet head according to claim 5,
The holes of the plate-like body from the pressure chamber side to the plurality are widened toward the pressure chamber,
An inkjet head characterized by that. The inkjet head according to any one of claims 1 to 6,
The communication channel other than the end portion is circular and has the same width, and the center thereof coincides with the center of the nozzle.
An inkjet head characterized by that. An ink jet head according to any one of claims 1 to 7,
An ink jet apparatus comprising: an ink supply unit that supplies ink to the ink jet head.

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