JP2004276433A - Ink jet recording head and ink jet recorder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ink jet recording head in which variation in ink ejection characteristics can be reduced while exhibiting good bubble discharging properties and driving area can be increased by arranging a pressure chamber efficiently, and to provide an ink jet recorder. <P>SOLUTION: The pressure chamber 14 has a substantially hexagonal planar shape where the corners are rounded. The line L connecting the centers of an ink supply opening 22 and a nozzle 12 is aligned with the long diagonal out of the diagonals of a parallelogram 40 formed by connecting the nozzle 12 and three adjacent nozzles 12. Furthermore, the pressure chamber 14 and an ink supply passage 18 are shaped line symmetrically to the line L. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an inkjet recording head that records an image by discharging ink, and an inkjet recording apparatus using the inkjet recording head.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, for example, an ink jet recording head shown in FIG. 17 has been disclosed as an ink jet recording head in which a number of nozzles for ejecting ink are arranged and ink droplets fly on a recording medium to record an image.
[0003]
A large number of nozzles 102 for discharging ink are arranged in the ink jet recording head 100, and each of the nozzles 102 communicates with a rectangular pressure chamber 104. The pressure chamber 104 is connected to an ink supply path 106 for supplying ink via a connection path 110. Further, the plurality of ink supply paths 106 communicate with an ink common flow path 108.
[0004]
As shown in FIG. 18, the ink supply path 106 is formed in a direction orthogonal to the flow direction of the ink common flow path 108, and a connection path 110 communicates with an upper portion of the ink supply path 106. As shown in FIG. 17, the nozzle 102 is disposed at the center of the pressure chamber 104, and the connection path 110 is connected near the center of one side of the pressure chamber 104.
[0005]
In such an ink jet recording head 100, the ink is guided from the common ink flow path 108 to the ink supply path 106, and the ink flows into the pressure chamber 104 from the upper connection path 110. At this time, the flow of the ink from the connection path 110 to the pressure chamber 104 is directed more toward the wall of the pressure chamber 104 than the direction of the nozzle 102 (see, for example, Patent Document 1).
[0006]
Further, the planar shape of the pressure chamber is not limited to a square as shown in FIG. 17, but a circular shape is also employed (for example, see Patent Document 2).
[0007]
Further, there has been proposed an ink jet recording head in which a large number of nozzles are arranged in a matrix, and an ink common flow path and a pressure chamber communicate with each other via a short ink supply path extending vertically (see, for example, Patent Document 3).
[0008]
[Patent Document 1]
JP-A-9-150513
[Patent Document 2]
JP-A-1-208146
[Patent Document 3]
JP 2001-334661 A
[0009]
[Problems to be solved by the invention]
However, the ink jet recording head has the following problems.
[0010]
In the ink jet recording head 100 shown in FIG. 17, since the direction of the connection path 110 is more toward the wall than the position of the nozzle 102 of the pressure chamber 104, the ink flow direction is biased in the pressure chamber 104, Stagnation spots are easily formed. For this reason, the bubbles are not discharged and remain in the stagnation portions, causing problems such as defective ink ejection.
[0011]
Further, when a plurality of nozzles are arranged in a matrix at equal intervals, it is difficult to efficiently arrange the plurality of pressure chambers and the ink supply paths communicating with the nozzles. If the ink supply path communicating with the pressure chamber is short as in the ink jet recording head described in Patent Document 3, variations in ink ejection characteristics are likely to occur. This causes image quality defects such as image unevenness.
[0012]
Further, in a circular pressure chamber as described in Patent Document 2, the number of pressure chambers is smaller than that in a case where a polygonal pressure chamber having the same area is formed on a plate of the same size, and the pressure chambers are arranged at high density. Can not.
[0013]
The present invention has been made in view of the above problems, and has as its object to provide an ink jet recording head and an ink jet recording apparatus which have good air bubble discharge properties and can reduce variations in ink ejection characteristics. Still another object of the present invention is to provide an ink jet recording head and an ink jet recording apparatus capable of efficiently arranging pressure chambers and increasing a driving area.
[0014]
[Means for Solving the Problems]
In order to solve the above problem, the ink jet recording head according to the first aspect of the present invention has a nozzle plate in which nozzles for ejecting ink droplets are formed in a matrix, and pressurized ink stored in communication with the nozzles. A pressure chamber, an ink supply path for supplying ink to the pressure chamber, and an ink supply port for guiding ink in a common ink pool to the ink supply path. The shape is substantially polygonal, and the shape of the pressure chamber and the shape of the ink supply path are formed to be line-symmetric with respect to a straight line connecting the center of the nozzle and the center of the ink supply port. It is characterized by:
[0015]
According to the inkjet recording head of the first aspect, the shape of the pressure chamber and the shape of the ink supply path are formed to be line-symmetric with respect to a straight line connecting the center of the nozzle and the center of the ink supply port. Therefore, the flow of the ink in the ink supply path and the pressure chamber becomes substantially equal to the straight line, and the ink flows stably from the ink supply path to the nozzle in the pressure chamber. Therefore, the number of ink stagnation points is reduced, and the air bubble discharging property can be improved.
[0016]
Furthermore, since the planar shape of the pressure chamber is substantially polygonal, large-area pressure chambers can be efficiently arranged, and the driving area of the actuator attached to the pressure chamber can be increased.
[0017]
3. An ink jet recording head according to claim 2, wherein the nozzle plate for discharging ink droplets is formed in a matrix, a pressure chamber communicating with the nozzle and pressurizing the stored ink, and the pressure chamber. An ink supply path for supplying ink to the ink supply port, and an ink supply port for guiding ink in a common ink pool to the ink supply path, wherein the planar shape of the pressure chamber is substantially polygonal, A straight line connecting the center of the nozzle and the center of the ink supply port is substantially co-linear with the longer diagonal line of the parallelogram diagonal line formed by connecting the nozzle and three adjacent nozzles. Wherein the shape of the pressure chamber and the shape of the ink supply path are formed to be line-symmetric with respect to this straight line.
[0018]
According to the ink jet recording head of the present invention, the line connecting the center of the nozzle and the center of the ink supply port is longer than the parallelogram diagonal line connecting the nozzle and three nozzles adjacent thereto. Since the ink supply path is set to be substantially on the same straight line as the diagonal line, the ink supply path connected to the pressure chamber can be efficiently disposed between the other two pressure chambers, and the ink supply path can be formed long. For this reason, the flow of the ink supplied into the pressure chamber is stabilized, and it is possible to reduce the occurrence of variations in the ink ejection characteristics. In addition, the flow of the ink flowing from the ink supply port into the pressure chamber through the ink supply path is substantially linear on the see-through plane, and the flow of the ink is less likely to stagnate. Further, since the shape of the pressure chamber and the shape of the ink supply path are formed so as to be line-symmetric with respect to the straight line, the flow of ink in the ink supply path and the pressure chamber becomes substantially equal to the straight line, Ink flows stably to the nozzle. Therefore, the number of ink stagnation points is reduced, and the air bubble discharging property can be improved.
[0019]
Furthermore, since the planar shape of the pressure chamber is substantially polygonal, large-area pressure chambers can be efficiently arranged, and the driving area of the actuator attached to the pressure chamber can be increased.
[0020]
Further, as described in claims 3 to 5, the planar shape of the pressure chamber according to claim 1 or 2 is substantially rhombic, substantially hexagonal, or long in the ink supply path direction. It is set appropriately in a circular shape. As a result, the pressure chambers having a large area can be efficiently arranged, and the driving area of the actuator attached to the pressure chamber can be increased. For this reason, a required amount of droplets can be obtained with a higher density arrangement.
[0021]
According to a sixth aspect of the present invention, in the ink jet recording head according to the first to fifth aspects, the opening connecting the ink supply path to the pressure chamber and the nozzle are provided in the pressure chamber. It is characterized by being located diagonally.
[0022]
According to the inkjet recording head of the sixth aspect, the ink that has flowed into the pressure chamber from the ink supply path through the opening flows in the diagonal nozzle direction of the pressure chamber, and the flow of the ink is stabilized. For this reason, the stagnation portion of the ink in the pressure chamber can be further reduced, and an excellent bubble discharging property can be obtained.
[0023]
An ink jet recording head according to the invention according to claim 7, wherein the nozzle plate for discharging ink droplets is formed in a matrix, a pressure chamber in which the stored ink is communicated with the nozzles and the stored ink is pressurized; In an ink jet recording head having two ink supply paths for supplying ink to a pressure chamber and an ink supply port for guiding ink in a common ink pool to the ink supply path, the pressure chamber has a substantially multi-planar shape. The center of the nozzle is located on a straight line connecting the centers of the two ink supply ports in a see-through plane, and the shape of the pressure chamber and the shape of the ink supply path are line-symmetric with respect to this straight line. It is characterized in that it is formed so that
[0024]
According to the inkjet recording head of the present invention, the center of the nozzle is located on a straight line connecting the centers of the two ink supply ports, and the shape of the pressure chamber and the shape of the ink supply path are linear with respect to this straight line. Since it is formed to be symmetric, the flow of ink flowing into the pressure chamber from the two ink supply paths is stabilized, and the flow of ink in the ink supply path and the pressure chamber is substantially equal to the straight line. It becomes. Therefore, the number of ink stagnation points is reduced, and the air bubble discharging property can be improved. Further, since the planar shape of the pressure chamber is substantially polygonal, large-sized pressure chambers can be efficiently arranged, and the driving area can be increased.
[0025]
An ink jet recording head according to the invention according to claim 8, wherein the nozzle plate that discharges the ink droplets is formed in a matrix shape, a pressure chamber that communicates with the nozzles and pressurizes the stored ink; In an ink jet recording head having two ink supply paths for supplying ink to a pressure chamber and an ink supply port for guiding ink in a common ink pool to the ink supply path, the pressure chamber has a substantially polygonal shape. The center of the nozzle is located on a straight line connecting the centers of the two ink supply ports in a see-through plane, and is a parallelogram diagonal formed by connecting the nozzle and three nozzles adjacent thereto. The long diagonal line is substantially co-linear with a straight line connecting the centers of the two ink supply ports in a see-through plane, and the shape of the pressure chamber and the It is characterized in that the shape of the supply channel is formed to be line-symmetric.
[0026]
According to the ink jet recording head of the eighth aspect, the center of the nozzle is located on the line connecting the centers of the two ink supply ports, and the center of the nozzle is defined by a parallelogram diagonal line connecting the nozzle and three nozzles adjacent thereto. Since the long diagonal line is set substantially on the same straight line as the line connecting the centers of the two ink supply ports, the flow of the ink flowing from the two ink supply ports into the pressure chamber through the ink supply path is seen through. It is almost linear on a plane, and stagnation does not easily occur in the flow of ink. Further, since the shape of the pressure chamber and the shape of the ink supply path are formed so as to be line-symmetric with respect to the straight line, the flow of ink in the two ink supply paths and the pressure chamber is substantially equal to the straight line. Be equal. Therefore, the number of ink stagnation points is reduced, and the air bubble discharging property can be improved. Further, the flow of the ink supplied to the pressure chamber is stabilized, and the variation in the ink ejection characteristics can be reduced.
[0027]
Furthermore, since the planar shape of the pressure chamber is substantially polygonal, large-sized pressure chambers can be efficiently arranged, and the driving area can be increased.
[0028]
Further, as described in claims 9 to 11, the planar shape of the pressure chamber according to claim 7 or 8 is substantially rhombic, substantially hexagonal, or long in the ink supply path direction. It is set appropriately in a circular shape. Thus, the pressure chambers having a large area can be efficiently arranged, and the driving area can be increased.
[0029]
An ink jet recording head according to a twelfth aspect of the present invention is the ink jet recording head according to any one of the first to eleventh aspects, wherein the connection part of the pressure chamber connected to the ink supply path is formed with a hole wall of the ink supply path. It is characterized by being parallel.
[0030]
According to the inkjet recording head of the twelfth aspect, the ink in the ink supply path flows from the connection portion into the pressure chamber. At this time, since the connection portion is parallel to the hole wall of the ink supply path, the ink is guided into the pressure chamber along the connection portion, and the flow of the ink supplied to the pressure chamber is stabilized. Therefore, the occurrence of ink stagnation can be further reduced.
[0031]
An ink jet recording apparatus according to a thirteenth aspect of the present invention uses any one of the ink jet recording heads according to the first to twelfth aspects.
[0032]
According to the ink-jet recording apparatus of the present invention, since the ink-jet recording head of the present invention is used, an apparatus which has good air bubble discharge property and little variation in ink ejection characteristics is realized. As a result, a high-quality image with few ejection defects can be obtained. Further, the driving area can be increased by efficiently arranging the pressure chambers, and a necessary amount of liquid droplets can be obtained with a higher density ink jet recording head.
[0033]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, a first embodiment of an ink jet recording head according to the present invention will be described with reference to FIGS.
[0034]
As shown in FIGS. 1, 2 and 4, the ink jet recording head 10 includes a nozzle 12 for discharging a plurality of ink droplets opened in a matrix, and a plurality of pressure chambers 14 for pressurizing the ink. Further, a nozzle communication chamber 16 that communicates the nozzle 12 with the pressure chamber 14, an ink supply path 18 that supplies ink to the pressure chamber 14, and a common ink pool 20 that guides ink to an ink supply port 22 of the ink supply path 18. And
[0035]
As shown in FIGS. 4 and 5, the inkjet recording head 10 includes a nozzle plate 24 in which the nozzles 12 are formed, a first ink pool plate 26 that forms the nozzle communication chamber 16 and the common ink pool 20, and a second ink pool plate 26. 2, an ink pool plate 28, a through plate 30 forming the nozzle communication chamber 16 and the ink supply port 22, an ink supply path plate 32 in which the ink supply path 18 is formed, and a pressure chamber in which the pressure chamber 14 is formed. The plate 34 is bonded in order, and then the surface of the nozzle plate 24 is coated with a water-repellent coating film, and the plurality of nozzles 12 are opened by an excimer laser. After the joining, the surface opposite to the nozzle 12 is in a state where the nozzle communication chamber 16, the pressure chamber 14, the ink supply path 18, and the ink supply port 22 are open.
[0036]
Further, as shown in FIG. 5, on the upper part of the pressure chamber plate 34, a vibrating plate 36 closing the upper surface of the pressure chamber 14, a piezoelectric element 45 adhered at a position facing the pressure chamber 14, and a piezoelectric element 45 An electric board 46 joined to the electric board 46 via a ball solder 48 is provided thereon.
The material of the nozzle plate 24 is polyimide, and the materials of the first and second ink pool plates 26 and 28, the through plate 30, and the ink supply path plate 32 are SUS.
[0037]
As shown in FIGS. 2 and 3, the planar shape of the pressure chamber 14 is a shape having a substantially hexagonal corner, and the opening 39 of the ink supply path 18 is directed toward the ink supply path 18 of the pressure chamber 14. Are provided on the projections 38 of the main body. The opening 39 is formed so as to be located at a diagonal of the nozzle communication chamber 16 of the pressure chamber 14.
[0038]
As shown in FIGS. 3 and 4, the ink supply path 18 has a linear and elongated cylindrical shape, and an opening 39 formed at one end of the ink supply path 18 has a protrusion 38 of the pressure chamber 14. The other end is communicated with the common ink pool 20 by the ink supply port 22. Then, as shown in FIG. 2, a straight line L connecting the center of the ink supply port 22 and the center of the nozzle 12 forms a parallelogram 40 formed by connecting the nozzle 12 and three nozzles 12 adjacent thereto. Are arranged so as to be on the same straight line between the long diagonal line and the perspective plane. Further, the shape of the pressure chamber 14 and the shape of the ink supply path 18 are formed to be line-symmetric with respect to the straight line L.
[0039]
Next, the operation of the inkjet recording head 10 according to the first embodiment will be described.
[0040]
A plurality of ink supply paths 18 communicate with the common ink pool 20 via ink supply ports 22, and the ink in the common ink pool 20 passes through the ink supply ports 22 and the ink supply paths 18 to each of the pressure chambers 14. Supplied to In the pressure chamber 14, when a voltage is applied to the piezoelectric element 45 from a power supply (not shown), the diaphragm 36 is deformed in the direction of the pressure chamber 14, and the ink in the pressure chamber 14 is pressurized. Accordingly, ink droplets are ejected from the nozzles 12 of the nozzle communication chamber 16.
[0041]
In such an ink jet recording head, as shown in FIG. 2, the flow 44 of the ink flowing from the ink supply port 22 into the pressure chamber 14 through the ink supply path 18 becomes substantially linear along the straight line L. The ink in the pressure chamber 14 flows in the direction of the nozzle 12 located at the diagonal of the ink supply path 18. Therefore, stagnation does not easily occur in the ink flow in the ink supply path 18 and the pressure chamber 14. Further, since the pressure chamber 14 and the ink supply path 18 are formed so as to be line-symmetric with respect to the straight line L in the ink flow direction, the ink flows almost uniformly. For this reason, ink stagnation points in the ink supply path 18 and the pressure chamber 14 are reduced, and bubbles can be prevented from remaining.
[0042]
In addition, since the elongated ink supply path 18 having a linear shape can be arranged, the flow of the ink supplied to the pressure chamber 14 is stabilized, and the occurrence of variations in the ink ejection characteristics can be reduced.
[0043]
Further, since the pressure chamber 14 has a substantially hexagonal shape with rounded corners, large-sized pressure chambers can be arranged efficiently, and the driving area can be increased.
[0044]
Next, a second embodiment according to the present invention will be described with reference to FIG.
[0045]
The members described in the first embodiment are denoted by the same reference numerals, and redundant description will be omitted.
[0046]
In the ink jet recording head of the second embodiment, as shown in FIG. 6, the planar shape of the pressure chamber 54 is substantially rhombic, and the opening 39 of the ink supply path 18 and the nozzle 12 are diagonally opposite to the rhombus. Is provided. Then, a straight line L connecting the center of the ink supply port 22 and the center of the nozzle 12 is arranged on the same straight line as the long diagonal line of the diagonal lines of the parallelogram 40 formed by connecting the four nozzles 12, and The pressure chamber 54 and the ink supply path 18 are formed so as to be line-symmetric with respect to the straight line L.
[0047]
Also in such an ink jet recording head, as in the first embodiment, the flow 56 of the ink flowing into the pressure chamber 54 through the ink supply path 18 is substantially linear on a see-through plane, and the ink flows in the direction of the nozzle 12. It flows smoothly. Further, the flow of the ink in the ink supply path 18 and the pressure chamber 54 becomes substantially uniform, and the flow of the ink in the ink supply path 18 and the pressure chamber 54 hardly stagnates. Therefore, it is possible to prevent bubbles from remaining in the ink supply path 18 and the pressure chamber 54.
[0048]
In addition, since the linear and long ink supply path 18 can be arranged, the flow of the ink supplied to the pressure chamber 54 is stabilized, and the occurrence of variations in the ink ejection characteristics can be reduced.
[0049]
Further, by providing the substantially rhombus-shaped pressure chambers 54, the large-area pressure chambers 54 can be efficiently arranged, and the driving area can be increased.
[0050]
Next, a third embodiment according to the present invention will be described with reference to FIG.
[0051]
The members described in the first embodiment are denoted by the same reference numerals, and redundant description will be omitted.
[0052]
In the ink jet recording head of the third embodiment, as shown in FIG. 7, the planar shape of the pressure chamber 64 is substantially hexagonal, and the opening 39 of the ink supply path 18 and the nozzle 12 are diagonally opposite to each other. Is provided. A straight line L connecting the center of the ink supply port 22 and the center of the nozzle 12 is arranged on the same straight line as a long diagonal line of the parallelogram 40 formed by connecting the four nozzles 12. The pressure chamber 64 and the ink supply path 18 are formed so as to be symmetrical with respect to the line.
[0053]
Also in such an ink jet recording head, similarly to the first embodiment, the flow 66 of the ink flowing into the pressure chamber 64 through the ink supply path 18 and flowing toward the nozzle 12 becomes substantially linear on a see-through plane. The flow of ink in the ink supply passage 18 and the pressure chamber 64 becomes substantially uniform. For this reason, stagnation does not easily occur in the flow of ink in the ink supply path 18 and the pressure chamber 64, and bubbles can be prevented from remaining.
[0054]
Further, since the elongated ink supply path 18 having a linear shape can be arranged, the flow of the ink supplied to the pressure chamber 64 is stabilized, and the occurrence of variations in the ink ejection characteristics can be reduced.
[0055]
Further, since the shape of the pressure chamber 64 is substantially hexagonal, the pressure chambers having a large area can be efficiently arranged, and the driving area can be increased.
[0056]
Next, a fourth embodiment according to the present invention will be described with reference to FIG.
[0057]
The members described in the first embodiment are denoted by the same reference numerals, and redundant description will be omitted.
[0058]
In the ink jet recording head of the fourth embodiment, as shown in FIG. 8, the planar shape of the pressure chamber 74 is an elliptical shape that is long in the direction of the ink supply path 18, and a straight portion 74a is formed in a part of the elliptical shape. Is formed. The opening 39 of the ink supply path 18 and the nozzle 12 are provided near both ends of the long diameter of the pressure chamber 74. A straight line L connecting the center of the ink supply port 22 and the center of the nozzle 12 is arranged on the same straight line as a long diagonal line of the parallelogram 40 formed by connecting the four nozzles 12. The pressure chamber 74 and the ink supply path 18 are formed so as to be symmetrical with respect to the line.
[0059]
Also in such an ink jet recording head, similarly to the first embodiment, the flow 76 of the ink flowing into the pressure chamber 74 through the ink supply path 18 and flowing toward the nozzle 12 becomes substantially linear on a see-through plane. The flow of ink in the ink supply passage 18 and the pressure chamber 74 becomes substantially uniform. For this reason, stagnation does not easily occur in the ink flow in the ink supply path 18 and the pressure chamber 74, and bubbles can be prevented from remaining.
[0060]
Further, since the linear and elongated ink supply path 18 can be arranged, the flow of the ink supplied to the pressure chamber 74 is stabilized, and the occurrence of variations in the ink ejection characteristics can be reduced.
[0061]
Further, since the shape of the pressure chamber 74 is elliptical, the pressure chambers having a large area can be efficiently arranged, and the driving area can be increased.
[0062]
Next, a fifth embodiment according to the present invention will be described with reference to FIG.
[0063]
The members described in the first embodiment are denoted by the same reference numerals, and redundant description will be omitted.
[0064]
In the ink jet recording head of the fifth embodiment, as shown in FIG. 9, the planar shape of the pressure chamber 84 is substantially rhombic, and a nozzle 82 is provided near the center of a diagonal line of the pressure chamber 84. . An opening 39 of the ink supply path 18 is provided at one end of a diagonal line of the pressure chamber 84. Further, a straight line L connecting the center of the ink supply port 22 and the center of the nozzle 12 is arranged on the same straight line as the long diagonal line of the parallelogram 40 formed by connecting the four nozzles 12. The pressure chamber 84 and the ink supply path 18 are formed such that the shapes thereof are symmetrical with respect to the line.
[0065]
Also in such an ink jet recording head, the flow 86 of the ink flowing into the pressure chamber 84 through the ink supply path 18 becomes substantially linear on the see-through plane, and the flow of the ink in the ink supply path 18 and the pressure chamber 84 Stagnation is unlikely to occur. Therefore, it is possible to reduce bubbles remaining in the ink supply path 18 and the pressure chamber 84.
[0066]
Further, since the linear and long ink supply path 18 can be arranged, the flow of the ink supplied to the pressure chamber 84 is stabilized, and the occurrence of variations in the ink ejection characteristics can be reduced. Further, the driving area can be increased by efficiently disposing the large-area pressure chamber 84.
[0067]
Next, a sixth embodiment according to the present invention will be described with reference to FIG.
[0068]
The members described in the first embodiment are denoted by the same reference numerals, and redundant description will be omitted.
[0069]
In the ink jet recording head of the sixth embodiment, as shown in FIG. 10, the planar shape of the pressure chamber 94 is substantially hexagonal, and a convex portion 96 protruding toward the ink supply path 18 near the apex of the hexagon. Is provided. The opening 39 of the ink supply path 18 is connected to the convex portion 96, and the nozzle 12 is provided at a diagonal of the opening 39. The convex portion 96 is formed with a straight portion 96a substantially parallel to the hole wall of the ink supply path 18.
[0070]
Also in such an ink jet recording head, as in the first embodiment, the flow 98 of the ink flowing into the pressure chamber 94 through the ink supply path 18 and flowing toward the nozzle 12 becomes substantially linear on a see-through plane, and Is almost even. Therefore, stagnation does not easily occur in the ink flow in the ink supply path 18 and the pressure chamber 94.
[0071]
Further, since the opening 39 connecting the ink supply path 18 to the pressure chamber 94 is provided in the convex part 96, the ink flowing into the pressure chamber 94 from the ink supply path 18 is formed in the shape of the straight part 96 a of the convex part 96. And the flow of the ink in the pressure chamber 94 is further stabilized. For this reason, it is possible to more reliably prevent bubbles from remaining in the pressure chamber 94. Further, since the flow of the ink supplied to the pressure chamber 94 is stabilized, it is possible to prevent the ink ejection characteristics from being varied.
[0072]
Next, a seventh embodiment according to the present invention will be described with reference to FIG.
[0073]
The members described in the first embodiment are denoted by the same reference numerals, and redundant description will be omitted.
[0074]
In the ink jet recording head of the seventh embodiment, as shown in FIG. 11, the planar shape of the pressure chamber 134 is substantially rhombic, and the opening 139 of the ink supply path 136 and the nozzle 12 are opposite to the rhombus. Is provided. The pressure chamber 134 and the ink supply path 136 are formed to be line-symmetric with respect to a straight line L connecting the center of the ink supply port 138 and the center of the nozzle 12.
[0075]
Also in such an ink jet recording head, the flow of ink flowing into the pressure chamber 134 through the ink supply path 136 and flowing in the direction of the nozzle 12 becomes substantially linear on a see-through plane. , The flow of the ink becomes almost uniform. Therefore, stagnation does not easily occur in the ink flow in the ink supply path 136 and the pressure chamber 134, and bubbles can be prevented from remaining.
[0076]
Further, since the linear and elongated ink supply path 136 can be arranged, the flow of the ink supplied to the pressure chamber 134 can be stabilized, and the occurrence of variations in the ink ejection characteristics can be reduced.
[0077]
Further, the pressure chambers 134 having a large area can be arranged efficiently, and the driving area can be increased.
[0078]
Next, an eighth embodiment according to the present invention will be described with reference to FIG.
[0079]
In addition, the description which overlaps with the first embodiment will be omitted.
[0080]
In the ink jet recording head according to the eighth embodiment, as shown in FIG. 12, the planar shape of the pressure chamber 154 is substantially rhombic, and a nozzle 152 is provided near the center of the pressure chamber 154. Openings 159 of two ink supply passages 156 communicate with diagonals of the pressure chamber 154. The ink supply path 156 is shorter than the ink supply path 18 of the first embodiment, and each of the two ink supply paths 156 is provided with an ink supply port 158 that communicates with a common ink pool (not shown). .
[0081]
In this ink jet recording head, the center of the nozzle 152 is located on a straight line L connecting the centers of the two ink supply ports 158, and the parallelogram 160 formed by connecting the nozzle 152 and three nozzles 152 adjacent thereto. Are arranged on the same straight line in a see-through plane as the straight line L connecting the centers of the two ink supply ports 158. Further, the pressure chamber 154 and the ink supply path 156 are formed to be line-symmetric with respect to the straight line L.
[0082]
Also in such an ink jet recording head, the ink flows into the pressure chamber 154 through the two ink supply paths 156 and flows in the direction of the nozzle 152, so that the ink flow 164 becomes substantially linear on a see-through plane, and the ink supply The flow of ink in the passage 156 and the pressure chamber 154 becomes substantially uniform. For this reason, a stagnation portion of the ink is hardly generated in the ink supply path 156 and the pressure chamber 154, and the bubble can be prevented from remaining. Further, the flow of the ink supplied to the pressure chamber 154 is also stabilized, and the occurrence of variations in the ink ejection characteristics can be reduced. Further, the pressure chambers 154 can be efficiently arranged, and the driving area can be increased.
[0083]
Next, a ninth embodiment according to the present invention will be described with reference to FIG.
[0084]
The members described in the eighth embodiment are denoted by the same reference numerals, and redundant description will be omitted.
[0085]
The ink jet recording head of the ninth embodiment is as shown in FIG. The pressure chamber 174 has a substantially hexagonal planar shape, and a nozzle 152 is provided near the center of the hexagon. The openings 159 of the two ink supply paths 156 communicate with each other at the diagonal of the pressure chamber 174.
[0086]
In such an ink jet recording head as well, the ink flow 176 flowing from the two ink supply paths 156 into the pressure chambers 174 and flowing toward the nozzles 152 is substantially linear on a see-through plane, and the ink supply paths 156 and the pressure chambers 174 are formed. The flow of the ink becomes substantially uniform within. For this reason, a stagnation portion of the ink hardly occurs in the ink supply path 156 and the pressure chamber 174, and it is possible to prevent bubbles from remaining. Further, the flow of the ink supplied to the pressure chamber 174 is also stabilized, and it is possible to reduce the occurrence of variations in the ink ejection characteristics. Further, the pressure chamber 174 having a large area can be efficiently arranged, and the driving area can be increased.
[0087]
Next, a tenth embodiment according to the present invention will be described with reference to FIG.
[0088]
The members described in the eighth embodiment are denoted by the same reference numerals, and redundant description will be omitted.
[0089]
In the ink jet recording head according to the tenth embodiment, as shown in FIG. 14, the planar shape of the pressure chamber 184 is an elliptical shape that is long in the direction of the ink supply path 156, and the nozzle is located near the center of the elliptical shape. 152 are provided. Openings 159 of the two ink supply paths 156 communicate with both ends of the oval.
[0090]
In such an ink jet recording head as well, the flow 186 of the ink flowing from the two ink supply paths 156 into the pressure chambers 184 and flowing toward the nozzles 152 is substantially linear on a see-through plane, and the ink supply paths 156 and the pressure chambers 184 are formed. The flow of the ink inside is also substantially equal. For this reason, ink stagnation points are less likely to occur in the ink supply path 156 and the pressure chamber 184, and bubbles can be prevented from remaining. Further, the flow of the ink supplied to the pressure chamber 184 is also stabilized, and the occurrence of variations in the ink ejection characteristics can be reduced. In addition, the pressure chamber 184 having a large area can be efficiently arranged to increase the driving area.
[0091]
Next, an eleventh embodiment according to the present invention will be described with reference to FIG.
[0092]
The members described in the eighth embodiment are denoted by the same reference numerals, and redundant description will be omitted.
[0093]
In the ink jet recording head according to the eleventh embodiment, as shown in FIG. 15, the planar shape of the pressure chamber 194 is substantially rhombic, and a nozzle 152 is provided near the center of the pressure chamber 194. Openings 199 of two ink supply paths 196 communicate with diagonals of the pressure chamber 194.
[0094]
In this ink jet recording head, the center of the nozzle 152 is located on a straight line L connecting the centers of the two ink supply ports 198, and the shapes of the pressure chamber 194 and the ink supply path 196 are line-symmetric with respect to this straight line L. It is formed as follows.
[0095]
In such an ink jet recording head as well, the ink flows into the pressure chamber 194 through the two ink supply paths 196 and flows in the direction of the nozzle 152, so that the flow of the ink becomes substantially linear on the see-through plane, and the ink supply path The flow of ink in the pressure chamber 196 and the pressure chamber 194 becomes substantially uniform. For this reason, a stagnation portion of the ink hardly occurs in the ink supply path 196 and the pressure chamber 194, and it is possible to prevent bubbles from remaining. Further, the flow of the ink supplied to the pressure chamber 194 is also stabilized, and it is possible to reduce the occurrence of variations in the ink ejection characteristics. Further, the pressure chambers 194 can be efficiently arranged, and the driving area can be increased.
[0096]
Next, an embodiment of an ink jet recording apparatus using the ink jet recording head of the present invention having the above configuration will be described with reference to FIG.
[0097]
An inkjet recording apparatus 200 shown in FIG. 16 includes a transport roller 206 that transports a recording medium P in the S direction, an inkjet recording head 202 of the present invention that ejects ink droplets onto the recording medium P to record an image, A carriage 203 that accommodates the recording head 202 and a transport unit 204 that scans the inkjet recording head 202 in an M direction orthogonal to the transport direction of the recording medium P are provided.
[0098]
In the inkjet recording apparatus 200, the recording medium P is transported in the S direction by the transport roller 206, and an image of the area BE on the recording medium P is written by the inkjet recording head 202 in one scan in the M direction. Then, the recording medium P is transported to a predetermined position in the S direction, and when the ink jet recording head 202 returns to the M direction, an image of the next area PE is written. Such operations are sequentially performed, and an image is formed on the recording medium P.
[0099]
In the ink jet recording apparatus 200, since the air bubble discharging property of the ink jet recording head 202 can be improved and variations in ink discharge characteristics can be reduced, problems such as defective ink discharge hardly occur. For this reason, it is possible to obtain a high-quality image without image quality defects.
[0100]
In addition, the ink jet recording in this specification is not limited to the recording of characters and images on recording paper. That is, the recording medium is not limited to paper, and the liquid to be ejected is not limited to ink. For example, discharging ink on polymer film or glass to create a display color filter, or discharging solder in a welded state on a substrate to form bumps for component mounting, etc. The present invention can be applied to all droplet ejecting apparatuses used.
[0101]
【The invention's effect】
As described above, according to the present invention, it is possible to improve the bubble discharging property in the ink jet recording head, and it is possible to solve problems such as defective ink ejection caused by residual bubbles. In addition, it is possible to reduce variations in the ink ejection characteristics, and it is possible to increase the driving area by arranging the pressure chambers at a high density.
[Brief description of the drawings]
FIG. 1 is a partial perspective view showing an ink jet recording head according to a first embodiment of the present invention.
FIG. 2 is a partial plan view showing the ink jet recording head according to the first embodiment of the present invention.
FIG. 3 is a plan view showing the ink jet recording head according to the first embodiment of the present invention.
FIG. 4 is an enlarged perspective view of the inkjet recording head according to the first embodiment of the present invention, which is indicated by X in FIG. 1;
FIG. 5 is an enlarged sectional view showing the inkjet recording head according to the first embodiment of the present invention.
FIG. 6 is a partial plan view showing an inkjet recording head according to a second embodiment of the present invention.
FIG. 7 is a partial plan view showing an inkjet recording head according to a third embodiment of the present invention.
FIG. 8 is a partial plan view showing an ink jet recording head according to a fourth embodiment of the present invention.
FIG. 9 is a partial plan view showing an inkjet recording head according to a fifth embodiment of the present invention.
FIG. 10 is a partial plan view showing an ink jet recording head according to a sixth embodiment of the present invention.
FIG. 11 is a partial plan view showing an ink jet recording head according to a seventh embodiment of the present invention.
FIG. 12 is a partial plan view showing an ink jet recording head according to an eighth embodiment of the present invention.
FIG. 13 is a partial plan view showing an inkjet recording head according to a ninth embodiment of the present invention.
FIG. 14 is a partial plan view showing an ink jet recording head according to a tenth embodiment of the present invention.
FIG. 15 is a partial plan view showing an ink jet recording head according to an eleventh embodiment of the present invention.
FIG. 16 is a perspective view illustrating an embodiment of an inkjet recording apparatus using the inkjet recording head of the present invention.
FIG. 17 is a plan view showing a conventional ink jet recording head.
FIG. 18 is an enlarged sectional view showing a conventional ink jet recording head.
[Explanation of symbols]
10 Inkjet recording head
12 nozzles
14 Pressure chamber
18 Ink supply path
20 Common Ink Pool
22 Ink supply port
39 opening
54 pressure chamber
64 pressure chamber
74 pressure chamber
82 nozzles
84 pressure chamber
94 pressure chamber
96 convex part (connection part)
134 pressure chamber
136 Ink supply path
138 Ink supply port
139 opening
152 nozzle
154 pressure chamber
156 Ink supply path
158 Ink supply port
159 opening
174 pressure chamber
184 pressure chamber
194 pressure chamber
196 Ink supply path
198 Ink supply port
199 opening
200 inkjet recording device
202 inkjet recording head
L straight line

Claims (13)

A nozzle plate in which nozzles for ejecting ink droplets are formed in a matrix, a pressure chamber communicating with the nozzle and pressurizing the stored ink, an ink supply path for supplying ink to the pressure chamber, and a common ink pool. And an ink supply port for guiding the ink to the ink supply path.
The planar shape of the pressure chamber is substantially polygonal,
An ink jet recording head, wherein the shape of the pressure chamber and the shape of the ink supply path are formed to be line-symmetric with respect to a straight line connecting the center of the nozzle and the center of the ink supply port. . A nozzle plate in which nozzles for ejecting ink droplets are formed in a matrix, a pressure chamber communicating with the nozzle and pressurizing the stored ink, an ink supply path for supplying ink to the pressure chamber, and a common ink pool. And an ink supply port for guiding the ink to the ink supply path.
The planar shape of the pressure chamber is substantially polygonal,
A straight line connecting the center of the nozzle and the center of the ink supply port is substantially the same as a long diagonal line of a parallelogram diagonal line formed by connecting the nozzle and three nozzles adjacent thereto in a transparent plane. An ink jet recording head which is on a line, and is formed such that the shape of the pressure chamber and the shape of the ink supply path are line-symmetric with respect to the straight line. 3. The ink jet recording head according to claim 1, wherein a planar shape of the pressure chamber is substantially rhombic. 3. The ink jet recording head according to claim 1, wherein a planar shape of the pressure chamber is substantially hexagonal. 3. The ink jet recording head according to claim 1, wherein the planar shape of the pressure chamber is an elliptical shape elongated in the direction of the ink supply path instead of a substantially polygonal shape. 6. The ink jet recording head according to claim 1, wherein an opening connecting the ink supply path to the pressure chamber and the nozzle are located at diagonals of the pressure chamber. A nozzle plate in which nozzles for ejecting ink droplets are formed in a matrix, a pressure chamber communicating with the nozzle and pressurizing the stored ink, and two ink supply paths for supplying ink to the one pressure chamber. And an ink supply port that guides the ink in the common ink pool to the ink supply path.
The planar shape of the pressure chamber is substantially polygonal,
The center of the nozzle is located on a straight line connecting the centers of the two ink supply ports in a see-through plane, and the shape of the pressure chamber and the shape of the ink supply path are line-symmetric with respect to this straight line. An ink jet recording head, which is formed. A nozzle plate in which nozzles for ejecting ink droplets are formed in a matrix, a pressure chamber communicating with the nozzle and pressurizing the stored ink, and two ink supply paths for supplying ink to the one pressure chamber. And an ink supply port that guides the ink in the common ink pool to the ink supply path.
The planar shape of the pressure chamber is substantially polygonal,
The center of the nozzle is located on a straight line connecting the centers of the two ink supply ports in a see-through plane, and is longer than a parallelogram diagonal formed by connecting the nozzle and three nozzles adjacent thereto. A diagonal line is substantially co-linear with a straight line connecting the centers of the two ink supply ports and a see-through plane, and the shape of the pressure chamber and the shape of the ink supply path are line-symmetric with respect to this straight line. An ink jet recording head, which is formed. 9. The ink jet recording head according to claim 7, wherein a planar shape of the pressure chamber is substantially rhombic. 9. The ink jet recording head according to claim 7, wherein the pressure chamber has a substantially hexagonal planar shape. 9. The ink jet recording head according to claim 7, wherein the pressure chamber has an elliptical shape elongated in a direction of the ink supply path instead of a substantially polygonal shape. The ink jet recording head according to claim 1, wherein a connection portion of the pressure chamber connected to the ink supply path is parallel to a hole wall of the ink supply path. An inkjet recording apparatus using the inkjet recording head according to claim 1.

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