JP2014019073A - Laminate, liquid ejection head and recording device using laminate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laminate which includes a position measurement part the position measurement accuracy of which can be enhanced, and to provide a liquid ejection head and a recording device using the laminate.SOLUTION: The laminate (channel member 4) in which at least three or more plates are laminated includes a position measurement part. When the continuously laminated two plates are a first plate 4j and a second plate 4k, the position measurement part includes: a first opening part 70a which penetrates a first plate 4j and is used for measuring a position; a second opening part 70b which penetrates the second plate 4k, overlaps the first opening part 70a and has a larger planer shape than the first opening part 70a; and a part of another plate 4l which is laminated so as to close the second opening 70b at the opposite side of the first opening 70a.

Description

  The present invention relates to a laminate having a position measuring unit capable of increasing the position measurement accuracy, and to a liquid discharge head and a recording apparatus using the same.

  In recent years, printing apparatuses using inkjet recording methods such as inkjet printers and inkjet plotters are not only printers for general consumers, but also, for example, formation of electronic circuits, manufacture of color filters for liquid crystal displays, manufacture of organic EL displays It is also widely used for industrial applications.

  In such an ink jet printing apparatus, a liquid discharge head for discharging liquid is mounted as a print head. This type of print head includes a heater as a pressurizing unit in an ink flow path filled with ink, heats and boiles the ink with the heater, pressurizes the ink with bubbles generated in the ink flow path, A thermal head system that ejects ink as droplets from the ink ejection holes, and a part of the wall of the ink channel filled with ink is bent and displaced by a displacement element, and the ink in the ink channel is mechanically pressurized, and the ink A piezoelectric method for discharging liquid droplets from discharge holes is generally known.

  In addition, in such a liquid discharge head, a serial type that performs recording while moving the liquid discharge head in a direction (main scanning direction) orthogonal to the conveyance direction (sub-scanning direction) of the recording medium, and main scanning from the recording medium There is a line type in which recording is performed on a recording medium conveyed in the sub-scanning direction with a liquid discharge head that is long in the direction fixed. The line type has the advantage that high-speed recording is possible because there is no need to move the liquid discharge head as in the serial type.

  In order to print droplets at a high density in any of the serial type and line type liquid discharge heads, the density of the discharge holes for discharging the droplets formed in the liquid discharge head is increased. There is a need.

  Therefore, the head body is connected to the manifold (common flow path) and the flow path member having the discharge holes connecting the manifold through the plurality of pressure chambers, and the plurality of displacement elements provided so as to cover the pressure chambers, respectively. It is known that the actuator unit having the structure is laminated (see, for example, Patent Document 1). This flow path member is constituted by a laminated body in which a plurality of plates each having a plurality of holes serving as a manifold and a pressure chamber are laminated. In order to manufacture such a laminated body, a hole for alignment is formed in the plate, or a hole for position measurement is formed so that the stacking accuracy can be measured after the plate is manufactured. As such holes, there are known holes in which the diameters gradually increase in the stacking direction are stacked concentrically to form a mortar shape (see, for example, Patent Document 2). Also, there is known a method of providing a hole penetrating the laminate, reducing the diameter of one of the penetrating holes, and measuring the position of the plate with transmitted light (for example, (See Patent Document 2).

JP 2010-522562 A JP 2008-265342 A

  However, a mortar-shaped measurement hole can in principle measure a large number of plates in one place, but in practice, the contrast of the area to be measured is not sufficient and the edge of the hole is measured. It was difficult to do. Also, if a measurement hole that penetrates the laminate is provided, a large number of holes are also opened in the plate on which the discharge holes are formed, so that ink that has drifted as mist during printing is collected in the holes. Therefore, there was a risk of affecting printing.

  Accordingly, an object of the present invention is to provide a laminate having a position measuring unit capable of increasing the position measurement accuracy, a liquid discharge head using the same, and a recording apparatus.

  The laminate of the present invention is a laminate in which at least three or more plates are laminated and has a position measuring unit, and the position measuring unit comprises two plates that are successively laminated, When the first plate and the second plate are used, the first plate penetrating the first plate, the first opening for measuring the position, and the second plate are penetrating. A second opening that overlaps with the first opening and has a larger planar shape than the first opening, and is stacked so as to close the opposite side of the second opening to the first opening. And a part of the other plate.

  Moreover, the laminate of the present invention is a laminate in which at least two or more plates are laminated and has a position measurement unit, and the position measurement unit includes two plates that are successively laminated. Are the first plate and the second plate, the first opening for measuring the position passing through the first plate, and the first plate of the second plate It has the recessed part with which the said 1st opening part provided in the side overlaps and a planar shape is larger than the said 1st opening part, It is characterized by the above-mentioned.

  Moreover, the laminate of the present invention is a laminate in which at least two or more plates are laminated and has a position measuring unit, and the position measuring unit is a through-hole penetrating one plate. A first opening for measuring a position, which is open on one surface of the plate, and an opening on the opposite side of the through hole to the first opening. A second opening that overlaps with the opening and has a larger planar shape than the first opening, and a part of another plate that is stacked so as to close the second opening It is characterized by that.

  The liquid discharge head of the present invention is a liquid discharge head having the laminate and a plurality of pressure units, and the laminate has a plurality of discharge holes in the plate at the end in the stacking direction, A plurality of pressurizing chambers respectively connected to the plurality of discharge holes, the plurality of pressurizing units can pressurize the plurality of pressurizing chambers, and the position measuring unit includes 1 opening part is arrange | positioned toward the lamination direction on the opposite side to the said plate which has these discharge holes, It is characterized by the above-mentioned.

  The recording apparatus of the present invention includes the liquid discharge head, a transport unit that transports a recording medium to the liquid discharge head, and a control unit that controls the liquid discharge head.

  According to the laminated body of the present invention, since the space wider in the plane direction than the first opening extends below the first opening, the edge of the first opening and the first opening The contrast with the inside of the part becomes high, and the position measurement of the first opening becomes easy. In addition, since it is not necessary to provide a through hole in the position measuring unit, it is not necessary to form a low required hole on one main surface of the laminate.

1 is a schematic configuration diagram of a color inkjet printer that is a recording apparatus including a liquid ejection head according to an embodiment of the present invention. FIG. 2 is a plan view of an ejection head body that constitutes the liquid ejection head of FIG. 1. FIG. 2 is a partial longitudinal sectional view of the liquid ejection head of FIG. 1. (A) is the fragmentary longitudinal cross-section of the flow-path member contained in the liquid discharge head of FIG. 1, (b) and (c) are the partial vertical cross-sections of the flow-path member in other embodiment of this invention. FIG.

  FIG. 1 is a schematic configuration diagram of a color ink jet printer which is a recording apparatus including a liquid discharge head according to an embodiment of the present invention. This color inkjet printer 1 (hereinafter referred to as printer 1) has four liquid ejection heads 2. These liquid discharge heads 2 are arranged along the conveyance direction of the printing paper P, and the liquid discharge heads 2 fixed to the printer 1 have an elongated shape extending in the direction from the front to the back in FIG. ing. This long direction is sometimes called the longitudinal direction.

  In the printer 1, a paper feed unit 114, a transport unit 120, and a paper receiver 116 are sequentially provided along the transport path of the printing paper P. In addition, the printer 1 is provided with a control unit 100 for controlling the operation of each unit of the printer 1 such as the liquid discharge head 2 and the paper feeding unit 114.

  The paper supply unit 114 includes a paper storage case 115 that can store a plurality of printing papers P, and a paper supply roller 145. The paper feed roller 145 can send out the uppermost print paper P among the print papers P stacked and stored in the paper storage case 115 one by one.

  Between the paper feed unit 114 and the transport unit 120, two pairs of feed rollers 118a and 118b and 119a and 119b are arranged along the transport path of the printing paper P. The printing paper P sent out from the paper supply unit 114 is guided by these feed rollers and further sent out to the transport unit 120.

  The transport unit 120 includes an endless transport belt 111 and two belt rollers 106 and 107. The conveyor belt 111 is wound around belt rollers 106 and 107. The conveyor belt 111 is adjusted to such a length that it is stretched with a predetermined tension when it is wound around two belt rollers. Thus, the conveyor belt 111 is stretched without slack along two parallel planes each including a common tangent line of the two belt rollers. Of these two planes, the plane closer to the liquid ejection head 2 is a transport surface 127 that transports the printing paper P.

  As shown in FIG. 1, a conveyance motor 174 is connected to the belt roller 106. The transport motor 174 can rotate the belt roller 106 in the direction of arrow A. The belt roller 107 can rotate in conjunction with the transport belt 111. Therefore, the conveyance belt 111 moves along the direction of arrow A by driving the conveyance motor 174 and rotating the belt roller 106.

  In the vicinity of the belt roller 107, a nip roller 138 and a nip receiving roller 139 are arranged so as to sandwich the conveyance belt 111. The nip roller 138 is urged downward by a spring (not shown). A nip receiving roller 139 below the nip roller 138 receives the nip roller 138 biased downward via the conveying belt 111. The two nip rollers are rotatably installed and rotate in conjunction with the conveyance belt 111.

  The printing paper P sent out from the paper supply unit 114 to the transport unit 120 is sandwiched between the nip roller 138 and the transport belt 111. As a result, the printing paper P is pressed against the transport surface 127 of the transport belt 111 and is fixed on the transport surface 127. The printing paper P is transported in the direction in which the liquid ejection head 2 is installed according to the rotation of the transport belt 111. The outer peripheral surface 113 of the conveyor belt 111 may be treated with adhesive silicon rubber. Thereby, the printing paper P can be securely fixed to the transport surface 127.

  The liquid discharge head 2 has a head body 2a at the lower end. The lower surface of the head body 2a is a discharge hole surface 4-1, in which a large number of discharge holes for discharging liquid are provided.

  Liquid droplets (ink) of the same color are ejected from the liquid ejection holes 8 provided in one liquid ejection head 2. Each liquid discharge head 2 is supplied with liquid from an external liquid tank (not shown). The liquid ejection holes 8 of each liquid ejection head 2 are open to the surface of the liquid ejection holes, and are in one direction (a direction parallel to the printing paper P and perpendicular to the conveyance direction of the printing paper P, and the longitudinal direction of the liquid ejection head 2. (Direction) at equal intervals, it is possible to print without gaps in one direction. The colors of the liquid ejected from each liquid ejection head 2 are, for example, magenta (M), yellow (Y), cyan (C), and black (K), respectively. Each liquid discharge head 2 is arranged with a slight gap between the lower surface of the liquid discharge head main body 13 and the transport surface 127 of the transport belt 111.

  The printing paper P transported by the transport belt 111 passes through the gap between the liquid ejection head 2 and the transport belt 111. At that time, droplets are ejected from the head main body 2 a constituting the liquid ejection head 2 toward the upper surface of the printing paper P. As a result, a color image based on the image data stored by the control unit 100 is formed on the upper surface of the printing paper P.

  A separation plate 140 and two pairs of feed rollers 121a and 121b and 122a and 122b are arranged between the transport unit 120 and the paper receiver 116. The printing paper P on which the color image is printed is conveyed to the peeling plate 140 by the conveying belt 111. At this time, the printing paper P is peeled from the transport surface 127 by the right end of the peeling plate 140. Then, the printing paper P is sent out to the paper receiving unit 116 by the feed rollers 121a to 122b. In this way, the printed printing paper P is sequentially sent to the paper receiving unit 116 and stacked on the paper receiving unit 116.

  Note that a paper surface sensor 133 is installed between the liquid ejection head 2 and the nip roller 138 that are the most upstream in the transport direction of the printing paper P. The paper surface sensor 133 includes a light emitting element and a light receiving element, and can detect the leading end position of the printing paper P on the transport path. The detection result by the paper surface sensor 133 is sent to the control unit 100. The control unit 100 can control the liquid ejection head 2, the conveyance motor 174, and the like so that the conveyance of the printing paper P and the printing of the image are synchronized based on the detection result sent from the paper surface sensor 133.

  Next, the liquid discharge head 2 of the present invention will be described. FIG. 2 is a plan view of the head main body 2a. FIG. 3 is a partial longitudinal sectional view including one liquid discharge element included in the discharge head 2 of FIG. FIG. 4A is a partial longitudinal sectional view of the position measuring unit 7 of the flow path member 4 included in the ejection head 2 of FIG.

  The liquid ejection head 2 includes a reservoir and a metal casing in addition to the head body 2a. Also. The head body 2 a includes a flow path member 4 and a piezoelectric actuator substrate 21 in which a displacement element (pressurizing unit) 30 is formed.

  The flow path member 4 constituting the head body 2a includes a manifold 5 which is a common flow path, a plurality of pressurizing chambers 10 connected to the manifold 5, and a plurality of discharge holes respectively connected to the plurality of pressurizing chambers 10. 8 and. The pressurizing chamber 10 opens to the upper surface of the flow path member 4, and the upper surface of the flow path member 4 is a pressurizing chamber surface 4-2. In addition, an opening 5a connected to the manifold 5 is provided on the upper surface of the flow path member 4, and liquid is supplied from the opening 5a. Further, the flow path member 4 is provided with a position measuring unit 70 so that the position can be measured from the direction of the pressurizing chamber surface 4-2.

  A piezoelectric actuator substrate 21 including a displacement element 30 is bonded to the upper surface of the flow path member 4, and each displacement element 30 is provided so as to be positioned on the pressurizing chamber 10. In addition, a signal transmission unit 92 such as an FPC (Flexible Printed Circuit) for supplying a signal to each displacement element 30 is connected to the piezoelectric actuator substrate 21. In FIG. 2, the outline of the vicinity of the signal transmission unit 92 connected to the piezoelectric actuator 21 is indicated by a dotted line so that the two signal transmission units 92 are connected to the piezoelectric actuator substrate 21. The electrodes formed on the signal transmission unit 92 that are electrically connected to the piezoelectric actuator 21 are arranged in a rectangular shape at the end of the signal transmission unit 92. The two signal transmission portions 92 are connected so that their ends come to the center portion in the short direction of the piezoelectric actuator substrate 21. The two signal transmission portions 92 extend from the central portion toward the long side of the piezoelectric actuator substrate 21.

  In addition, a driver IC is mounted on the signal transmission unit 92. The driver IC is mounted so as to be pressed against the metal casing, and the heat of the driver IC is transmitted to the metal casing and dissipated to the outside. A drive signal for driving the displacement element 30 on the piezoelectric actuator substrate 21 is generated in the driver IC. A signal for controlling the generation of the drive signal is generated by the control unit 100 and input from the end of the signal transmission unit 92 opposite to the side connected to the piezoelectric actuator substrate 21. A circuit board or the like is provided in the liquid ejection head 2 between the control unit 100 and the signal transmission unit 92 as necessary.

  The head body 2 a has one piezoelectric actuator substrate 21 including a flat plate-like flow path member 4 and a displacement element 30 connected on the flow path member 4. The planar shape of the piezoelectric actuator substrate 21 is rectangular, and is arranged on the upper surface of the flow path member 4 so that the long side of the rectangle is along the longitudinal direction of the flow path member 4.

  Two manifolds 5 are formed inside the flow path member 4. The manifold 5 has an elongated shape that extends from one end side in the longitudinal direction of the flow path member 4 to the other end side, and the manifold opening 5a that opens to the upper surface of the flow path member 4 at both ends. Is formed. By supplying the liquid from both ends of the manifold 5 to the flow path member 4, it is possible to prevent the liquid from being insufficiently supplied. Further, as compared with the case where the liquid is supplied from one end of the manifold 5, the difference in pressure loss caused when the liquid flows through the manifold 5 can be reduced to about half, so that the variation in the liquid discharge characteristics can be reduced. Further, in order to reduce the difference in pressure loss, it is conceivable to supply near the center of the manifold 5 or from several places along the manifold 5, but in such a structure, the width of the liquid discharge head 2 is considered. And the spread in the width direction of the liquid discharge head 2 in the arrangement of the discharge holes 8 also increases. Such an arrangement is not preferable because the influence of the deviation of the angle at which the liquid ejection head 2 is attached to the printer 1 on the printing result is increased. Even when printing is performed using a plurality of liquid ejection heads 2, the area in which the entire ejection holes 8 of the plurality of liquid ejection heads 2 are arranged increases, so that the relative position accuracy of the plurality of liquid ejection heads 2 is increased. Is not preferable because the influence on the printing result becomes large. Therefore, in order to reduce the difference in pressure loss while reducing the width of the liquid discharge head 2, it is preferable to supply from both ends of the manifold 5.

  In the manifold 5, at least a central portion in the length direction, which is a region connected to the pressurizing chamber 10, is partitioned by a partition wall 15 provided at an interval in the width direction. The partition wall 15 has the same height as the manifold 5 in the central portion in the length direction, which is a region connected to the pressurizing chamber 10, and completely separates the manifold 5 into a plurality of sub-manifolds 5b. By doing so, it is possible to provide the discharge hole 8 and a descender connected from the discharge hole 8 to the pressurizing chamber 10 so as to overlap with the partition wall 15 when seen in a plan view.

  In FIG. 2, the whole of the manifold 5 excluding both ends is partitioned by a partition wall 15. In addition to this, other than one of the two end portions may be partitioned by the partition wall 15. In addition, only the vicinity of the opening 5a opened on the upper surface of the flow path member 4 is not partitioned, and a partition wall may be provided in the depth direction of the flow path member 4 from the opening 5a. In any case, it is preferable that both ends of the manifold 5 are not partitioned by the partition wall 15 because the flow resistance is reduced and the supply amount of the liquid can be increased because there is a portion that is not partitioned.

  The portion of the manifold 5 divided into a plurality of parts may be referred to as a sub-manifold 5b. In this embodiment, two manifolds 5 are provided independently, and openings 5a are provided at both ends. One manifold 5 is provided with seven partition walls 15 and divided into eight sub-manifolds 5b. The width of the sub-manifold 5b is larger than the width of the partition wall 15, so that a large amount of liquid can flow through the sub-manifold 5b. In addition, the length of the seven partition walls 15 becomes longer as they are closer to the center in the width direction. At both ends of the manifold 5, the ends of the partition walls 15 are closer to the ends of the manifold 5 as the partition walls 15 are closer to the center in the width direction. It ’s close. As a result, the flow resistance generated by the outer wall of the manifold 5 and the flow resistance generated by the partition wall 15 are balanced, and the individual supply flow that is the portion connected to the pressurizing chamber 10 in each sub-manifold 5b. The pressure difference of the liquid at the end of the region where the channel 14 is formed can be reduced. Since the pressure difference in the individual supply channel 14 leads to a pressure difference applied to the liquid in the pressurizing chamber 10, the discharge variation can be reduced if the pressure difference in the individual supply channel 14 is reduced.

  A support body is provided in the sub-manifold 5b so as to cross the width direction. The support body connects adjacent partition walls 15, or connects the partition wall 15 at the end and the wall of the manifold 5. The flow path member 4 has a structure in which flat plates 4a to 4l are laminated, and the support supports a partition portion that becomes the partition wall 15 in the manufacturing process. By having such a structure, the flow path member 4 in which each flow path is built can be produced only by stacking the plates 4a to 4l. In this embodiment, a partition part will drop from a plate, if there is no support body. Further, if the structure is such that the end portion in the length direction of the partition portion is connected to the plate, the partition portion will not fall off, but the partition portion serving as the partition wall 15 that partitions the sub-manifold 5b long in one direction is supported. Without the body 17, stacking deviation is likely to occur in the width direction of the sub-manifold 5b. for that reason. By providing the support so as to cross the sub-manifold 5b in the width direction, the manufacturing accuracy of the flow path can be increased.

  The flow path member 4 is formed by two-dimensionally expanding a plurality of pressurizing chambers 10. The pressurizing chamber 10 is a hollow region having a substantially rhombic planar shape with rounded corners.

  The pressurizing chamber 10 is connected to one sub-manifold 5b through an individual supply channel 14. Along with one sub-manifold 5b, two rows of pressurizing chambers, which are rows of pressurizing chambers 10 connected to the sub-manifold 5b, are provided on each side of the sub-manifold 5b. . Accordingly, 16 rows of pressurizing chambers are provided for one manifold 5, and 32 rows of pressurizing chambers are provided in the entire head body 2a. The interval in the longitudinal direction of the pressurizing chamber 10 in each pressurizing chamber row is the same, for example, 37.5 dpi.

  The pressurizing chamber 10 connected to one manifold 5 is arranged on a lattice that forms rows and columns along each outer side of the rectangular piezoelectric actuator substrate 21. As a result, the individual electrodes 25 formed on the pressurizing chamber 10 are arranged at equal distances from the outer side of the piezoelectric actuator substrate 21. Therefore, when forming the individual electrodes 25, the piezoelectric actuator substrate is formed. 21 can be hardly deformed. When the piezoelectric actuator substrate 21 and the flow path member 4 are joined, if this deformation is large, stress may be applied to the displacement element 30 near the outer side, resulting in variations in displacement characteristics. However, by reducing the deformation, The variation can be reduced. Further, since the dummy pressurizing chamber row of the dummy pressurizing chamber 16 is provided outside the pressurizing chamber row closest to the outer side, it is possible to make it less susceptible to deformation. The pressurizing chambers 10 belonging to the pressurizing chamber row are arranged at equal intervals, and the individual electrodes 25 corresponding to the pressurizing chamber rows are also arranged at equal intervals. The pressurizing chamber rows are arranged at equal intervals in the short direction, and the rows of the individual electrodes 25 corresponding to the pressurizing chamber rows are also arranged at equal intervals in the short direction. Thereby, it is possible to eliminate a portion where the influence of the crosstalk becomes particularly large.

  In this embodiment, the pressurizing chambers 10 are arranged in a lattice shape, but may be arranged in a staggered manner so that corners are located between the pressurizing chambers 10 belonging to the adjacent pressure chamber rows 11. In this way, since the distance between the pressurizing chambers 10 belonging to the adjacent pressurizing chamber row becomes longer, crosstalk can be further suppressed.

  Regardless of how the pressurizing chamber rows are arranged, when the flow path member 4 is viewed in plan, the pressurizing chamber 10 belonging to one pressurizing chamber row belongs to the pressurizing chamber 10 belonging to the adjacent pressurizing chamber row. By arranging the liquid discharge heads 2 so as not to overlap in the longitudinal direction of the liquid discharge head 2, crosstalk can be suppressed. On the other hand, if the distance between the pressurizing chamber rows is increased, the width of the liquid discharge head 2 is increased, so that the accuracy of the installation angle of the liquid discharge head 2 with respect to the printer 1 and the use of a plurality of liquid discharge heads 2 are increased. In addition, the influence of the relative position accuracy of the liquid ejection head 2 on the printing result is increased. Therefore, by making the width of the partition wall 15 smaller than that of the sub-manifold 5b, the influence of the accuracy on the printing result can be reduced.

  The pressurizing chambers 10 connected to one sub-manifold 5b form two pressurizing chamber rows, and the discharge holes 8 connected to the pressurizing chambers 10 belonging to one pressurizing chamber row have one discharge hole 8. A discharge hole array is formed. The discharge holes 8 connected to the pressurizing chambers 10 belonging to the two pressurizing chamber rows open on different sides of the sub manifold 5b. The partition wall 15 is provided with two discharge hole arrays. The discharge holes 8 belonging to each of the discharge hole arrays are connected to the sub-manifold 5b near the discharge hole 8 via the pressurizing chamber 10. Yes. If the discharge hole 8 connected to the adjacent sub-manifold 5b via the pressurizing chamber row is arranged so as not to overlap in the longitudinal direction of the liquid discharge head 2, the flow connecting the pressurizing chamber 10 and the discharge hole 8 Since crosstalk between roads can be suppressed, crosstalk can be further reduced. If the entire flow path connecting the pressurizing chamber 10 and the discharge hole 8 is arranged so as not to overlap in the longitudinal direction of the liquid discharge head 2, crosstalk can be further reduced.

In addition, the width of the liquid discharge head 2 can be reduced by arranging the pressurizing chamber 10 and the sub-manifold 5b so as to overlap each other in plan view. When the ratio of the overlapping area to the area of the pressurizing chamber 10 is 80% or more, and further 90% or more, the width of the liquid discharge head 2 can be further reduced. Further, the bottom surface of the pressurizing chamber 10 where the pressurizing chamber 10 and the sub-manifold 5b overlap is less rigid than the case where the pressurizing chamber 10 and the sub-manifold 5b do not overlap. There is a risk of variation. By making the ratio of the area of the pressurizing chamber 10 overlapping the sub-manifold 5b to the area of the entire pressurizing chamber 10 substantially the same in each pressurizing chamber 10, the rigidity of the bottom surface constituting the pressurizing chamber 10 is increased. Variations in ejection characteristics due to changes can be reduced. Here, “substantially the same” means that the difference in area ratio is 10% or less, particularly 5%.
Say the following.

  A plurality of pressurizing chambers are formed by a plurality of pressurizing chambers 10 connected to one manifold 5. Since there are two manifolds 5, there are two pressurizing chamber groups. The arrangement of the pressurizing chambers 10 related to ejection in each pressurizing chamber group is the same, and is arranged to be translated in the lateral direction. These pressurizing chambers 10 are arranged over almost the entire surface although there are portions where the gaps between the pressurizing chamber groups are slightly wide in the region facing the piezoelectric actuator substrate 21 on the upper surface of the flow path member 4. . That is, the pressurizing chamber group formed by these pressurizing chambers 10 occupies an area having almost the same size and shape as the piezoelectric actuator substrate 21. Further, the opening of each pressurizing chamber 10 is closed by bonding the piezoelectric actuator substrate 21 to the upper surface of the flow path member 4.

  A descender connected to the discharge hole 8 opened in the discharge hole surface 4-1 on the lower surface of the flow path member 4 extends from a corner portion of the pressurizing chamber 10 facing the corner portion where the individual supply flow path 14 is connected. ing. The descender extends in a direction away from the pressurizing chamber 10 in plan view. More specifically, the pressurizing chamber 10 extends away from the direction along the long diagonal line while being shifted to the left and right with respect to that direction. As a result, the discharge chambers 8 can be arranged at an interval of 1200 dpi as a whole, while the pressurization chambers 10 are arranged in a lattice pattern in which the intervals in the respective pressurization chamber rows are 37.5 dpi.

  In other words, when the discharge holes 8 are projected so as to be orthogonal to a virtual straight line parallel to the longitudinal direction of the flow path member 4, 16 pieces connected to each manifold 5 within a range of the virtual straight line. In other words, a total of 32 discharge holes 8 are equally spaced at 1200 dpi. Thus, by supplying the same color ink to all the manifolds 5, an image can be formed with a resolution of 1200 dpi in the longitudinal direction as a whole. Further, one discharge hole 8 connected to one manifold 5 is equally spaced at 600 dpi within the above-described imaginary straight line range. As a result, by supplying different colors of ink to the respective manifolds 5, it is possible to form two-color images with a resolution of 600 dpi in the longitudinal direction as a whole. In this case, if two liquid ejection heads 2 are used, an image of four colors can be formed at a resolution of 600 dpi, and printing accuracy is higher and printing settings are easier than using a liquid ejection head capable of printing at 600 dpi. Can be.

  Furthermore, a reservoir may be joined to the flow path member 4 in the liquid ejection head 2 so as to stabilize the liquid supply from the opening 5a of the manifold. The reservoir is provided with a flow path that branches the liquid supplied from the outside and is connected to the two openings 5a, so that the liquid can be stably supplied to the two openings. By making the flow path lengths after branching substantially equal, temperature fluctuations and pressure fluctuations of the liquid supplied from the outside are transmitted to the openings 5a at both ends of the manifold 5 with a small time difference. Variations in droplet ejection characteristics can be further reduced. By providing a damper in the reservoir, the liquid supply can be further stabilized. Further, a filter may be provided so as to prevent foreign matters in the liquid from moving toward the flow path member 4. Furthermore, a heater may be provided so as to stabilize the temperature of the liquid toward the flow path member 4.

Individual electrodes 25 are formed at positions facing the pressurizing chambers 10 on the upper surface of the piezoelectric actuator substrate 21. The individual electrode 25 includes an individual electrode main body 25a that is slightly smaller than the pressurizing chamber 10 and has a shape substantially similar to the pressurizing chamber 10, and an extraction electrode 25b that is extracted from the individual electrode main body 25a. In the same manner as the pressurizing chamber 10, the individual electrode 25 constitutes an individual electrode row and an individual electrode group. In addition, a common electrode surface electrode is formed on the upper surface of the piezoelectric actuator substrate 21 and is electrically connected to the common electrode 24 via a via hole. The surface electrodes for the common electrode are formed in two rows along the longitudinal direction at the central portion in the short direction of the piezoelectric actuator substrate 21 and are formed in one row along the short direction near the end in the longitudinal direction. Yes. The common electrode surface electrode shown in the figure is formed intermittently on a straight line, but may be formed continuously on a straight line.

  The piezoelectric actuator substrate 21 is formed by laminating and firing a piezoelectric ceramic layer 21a having a via hole, a common electrode 24, and a piezoelectric ceramic layer 21b as will be described later, and then forming the individual electrode 25 and the common electrode surface electrode in the same process. Is preferred. The positional variation between the individual electrode 25 and the pressurizing chamber 10 greatly affects the ejection characteristics, and if the individual electrode 25 is formed and then fired, the piezoelectric actuator substrate 21 may be warped. When the substrate 21 is joined to the flow path member 4, stress is applied to the piezoelectric actuator substrate 21, and the displacement may vary due to the influence. Therefore, the individual electrode 25 is formed after firing. Similarly, the surface electrode for the common electrode may be warped, and the formation of the electrode simultaneously with the individual electrode 25 increases the positional accuracy and simplifies the process. The electrodes are formed in the same process.

  Such positional variations of via holes due to firing shrinkage that may occur when firing the piezoelectric actuator substrate 21 mainly occur in the longitudinal direction of the piezoelectric actuator substrate 21, so the manifold 5 having an even number of common electrode surface electrodes. In other words, it is provided at the center in the short direction of the piezoelectric actuator substrate 21, and the surface electrode for the common electrode has a long shape in the longitudinal direction of the piezoelectric actuator substrate 21. And the common electrode surface electrode can be prevented from being electrically disconnected due to misalignment.

  Two signal transmission portions 92 are arranged and bonded to the piezoelectric actuator substrate 21 from the two long sides of the piezoelectric actuator substrate 21 toward the center. At this time, the connection is facilitated by forming the connection electrode 26 and the common electrode connection electrode on the lead electrode 25b and the common electrode surface electrode of the piezoelectric actuator substrate 21a, respectively, and connecting them. At that time, if the area of the common electrode surface electrode and the common electrode connection electrode is made larger than the area of the connection electrode 26, the end of the signal transmission unit 92 (the end and the end in the longitudinal direction of the piezoelectric actuator substrate 21). Since the connection on the surface can be made stronger by the connection on the surface electrode for the common electrode, the signal transmission part 92 can be hardly separated from the end.

  Further, the discharge hole 8 is arranged at a position avoiding the area facing the manifold 5 arranged on the lower surface side of the flow path member 4. Further, the discharge hole 8 is disposed in a region facing the piezoelectric actuator substrate 21 on the lower surface side of the flow path member 4. These discharge holes 8 occupy a region having almost the same size and shape as the piezoelectric actuator substrate 21 as a group, and the displacement elements 30 of the corresponding piezoelectric actuator substrate 21 are displaced to displace the discharge holes 8 from the discharge holes 8. Droplets can be ejected.

  The flow path member 4 included in the head main body 2a has a laminated structure in which a plurality of plates are laminated. These plates are a cavity plate 4a, a base plate 4b, an aperture plate 4c, a supply plate 4d, manifold plates 4e to j, a cover plate 4k, and a nozzle plate 4l in order from the upper surface of the flow path member 4. A number of holes are formed in these plates. Since the thickness of each plate is about 10 to 300 μm, the formation accuracy of the holes to be formed can be increased. Each plate is aligned and laminated so that these holes communicate with each other to form the individual flow path 12 and the manifold 5. In the head main body 2a, the pressurizing chamber 10 is on the upper surface of the flow path member 4, the manifold 5 is on the inner lower surface side, the discharge holes 8 are on the lower surface, and the parts constituting the individual flow path 12 are close to each other in different positions. The manifold 5 and the discharge hole 8 are connected via the pressurizing chamber 10.

The holes related to ejection formed in each plate will be described. These holes include the following. The first is the pressurizing chamber 10 formed in the cavity plate 4a. Second, there is a communication hole that constitutes an individual supply channel 14 that is connected from one end of the pressurizing chamber 10 to the manifold 5. This communication hole is formed in each plate from the base plate 4b (specifically, the inlet of the pressurizing chamber 10) to the supply plate 4c (specifically, the outlet of the manifold 5). The individual supply flow path 14 includes a squeeze 6 that is formed in the aperture plate 4c and is a portion where the cross-sectional area of the flow path is small.

  Third, there is a communication hole constituting a flow path communicating from the other end of the pressurizing chamber 10 to the discharge hole 8, and this communication hole is referred to as a descender (partial flow path) in the following description. The descender is formed on each plate from the base plate 4b (specifically, the outlet of the pressurizing chamber 10) to the nozzle plate 4l (specifically, the discharge hole 8). The hole of the nozzle plate 41 is opened as a discharge hole 8 having a diameter of 10 to 40 μm, for example, which is open to the outside of the flow path member 4, and the diameter increases toward the inside. . Fourthly, communication holes constituting the manifold 5. The communication holes are formed in the manifold plates 4e to 4j. Holes are formed in the manifold plates 4e to 4j so that the partition portions to be the partition walls 15 remain so as to constitute the sub-manifold 5b. The partition portion in each manifold plate 4e-j is connected to each manifold plate 4e-j by a half-etched support portion.

  The first to fourth communication holes are connected to each other to form an individual flow path 12 from the liquid inflow port (outlet of the manifold 5) to the discharge hole 8 from the manifold 5. The liquid supplied to the manifold 5 is discharged from the discharge hole 8 through the following path. First, from the manifold 5, it enters the individual supply flow path 14 and reaches one end of the throttle 6. Next, it proceeds horizontally along the extending direction of the restriction 6 and reaches the other end of the restriction 6. From there, it reaches one end of the pressurizing chamber 10 upward. Furthermore, it progresses horizontally along the extending direction of the pressurizing chamber 10 and reaches the other end of the pressurizing chamber 10. While moving little by little in the horizontal direction from there, it proceeds mainly downward and proceeds to the discharge hole 8 opened in the lower surface.

  Next, the position measuring unit 70 capable of measuring the stacking accuracy of each plate will be described. In addition to measuring the stacking accuracy, the position measuring unit 70 may be used for other position measurements such as positioning in the manufacturing process and positioning of the head body 2a.

  Basically, the position measuring unit 70 is preferably provided so that the positions of all the plates can be measured, but the position measuring unit 70 of the present embodiment is a plate above the third plate 4j from the bottom. Since only measurement is possible, another form of the position measuring unit 70 is provided for the plates 4k and 4l.

The flow path member 4 is provided with a total of 24 position measuring units 70, each of which measures the respective plates, including those according to the embodiment of the present invention and those that are not. One position measuring unit 70 for measuring one plate is provided at each end of the range in which the region where the pressurizing chamber 10 is provided is extended in the longitudinal direction. By being provided at both ends in the longitudinal direction, a representative position of the entire plate can be measured. In order to increase the measurement accuracy, the distance between the two position measurement units 70 should be 2.5 cm or more, preferably 5 cm or more, particularly 10 cm or more. The position measuring unit 70 on the upper side of FIG. 2 is for measuring the plates 4a, 4b... Plate 4l in order from the right, and the position measuring unit 70 on the lower side of FIG. In order, the plate 4a, the plate 4b,..., The plate 4l are measured. Therefore, the center of gravity in the planar direction of the two position measuring units 70 (measurement portions) for measuring the plate 4a is the center of the flow path member. Similarly, the center of gravity in the planar direction of the two position measuring units 70 (the parts to be measured) for measuring the plates 4b to 44l is also the center of the flow path member, and the positions coincide with these. Thereby, if the position of the position measurement part 70 is measured and averaged, the relative positional accuracy of the plates 4a to 4l can be measured. As the position measurement part, if the holes are arranged concentrically and the diameter is gradually increased in the stacking direction, and a mortar-shaped one is used, measurement can be performed at one position measurement part. Although it seems preferable at first glance, in practice, it is difficult to determine an edge in position measurement, and the accuracy may not be sufficient.

  The position measuring unit 70 according to the embodiment of the present invention will be described with reference to the longitudinal sectional view of FIG. 4A is for measuring the plate 4j. The plate 4j has a first opening 70a that is a through hole for measuring the position. A second opening 70b, which is a through-hole having a larger planar shape than the first opening 70a, is opened in the lower plate 4k so as to overlap with the first opening 70a. The opposite side of the second opening 70b from the first opening 70a is closed by the plate 4l. The plates 4 a to 4 i above the first opening 70 a have a third opening 70 c so that the first opening 70 a can be seen from above the flow path member 4. ing. Note that the third opening 70c does not need to be open when used only during the manufacturing process.

  In the state where the position measuring unit 70 is laminated in this manner, the position measuring unit 70 is viewed from above the flow path member 4 and the position of the first opening is measured. If the first opening 70a is immediately closed by the plate 4k immediately below, the upper surface of the plate 4j, the inner wall of the first opening 70a, and the upper surface of the plate 4k are continuous surfaces. The boundary is difficult to see. This becomes conspicuous when the difference in color tone is small due to the same or approximate material of each plate. Further, when the diameter of the opening 70a is equal to or larger than the thickness of the plate 4j, particularly twice or more, it looks as if the upper surface of the plate 4j and the upper surface of the plate 4k are continuous. Therefore, it is difficult to optically visually recognize the inner wall of the first opening 70a. On the other hand, according to the above-described structure, a space that is wider than the first opening 70a is provided by the second opening 70b below the first opening 70a, so that the plate The boundary between the upper surface of 4j and the upper surface of the plate 4k is easily visible, and the measurement accuracy can be increased. At this time, it is preferable that the closing plate does not transmit light so as to be hardly affected by the outside.

  Further, with such a structure, when adhesive lamination is performed, it is possible to suppress a decrease in measurement accuracy due to an adhesive overflowing from the interlayer below the opening 70a.

  When only the ease of measurement and position accuracy are considered, it is conceivable to perform measurement with transmitted light from below without blocking the lower side of the position measurement unit 70 with a plate, but in the liquid discharge head 2, the discharge hole surface 4 If -1 has a large number of irregularities, the liquid that has become a mist during printing accumulates on the recording medium, and the liquid remains in the irregularities after wiping the ejection hole surface 4-1, which is not preferable.

  Such a position measuring unit 70 is provided with a first opening 70a opened to the plates 4a to 4j so that the positions of the plates 4a to 4j can be measured. What is provided in the plates 4a to 4i may be the one shown in FIG. 4A shifted in the stacking direction (that is, a plate having no holes is disposed under the position measuring unit 70). A plurality of plates in which the second opening 70b is opened may be arranged under the first opening 70a, and the second opening 70b may be closed with the plate below the plate.

  When laminating the plates by bonding, an escape groove for allowing the adhesive to escape is preferably formed in the plate in order to prevent the adhesive from protruding into the flow path. If this escape groove is connected to the hole of the position measuring unit 70, excess air and adhesive can be transmitted to the position measuring unit 70 through the escape groove. If excess air and adhesive are allowed to escape, air remaining between the plates and excess adhesive will be reduced, and stable lamination can be achieved. Even if a part of the adhesive enters the position measuring unit 70, there is a distance to the first opening 70a that is actually measured, so that the measurement can be prevented.

  Although it depends on the thickness of each plate, in order to make the measurement conditions as uniform as possible, the first opening 70b is provided only in the plate directly below the first opening 70a and is closed by the plate below it. Is preferred. Further, when the thicknesses of the respective plates are different, the plate on which the second opening 70b is provided may be determined so that the difference in the total height of the second opening 70b is reduced.

  The first opening 70a is preferably circular so that it can be easily measured. The diameter is, for example, 100 to 1 mm. Although the shape of the second opening 70b is not particularly defined, the center of the first opening 70a is the center, and the diameter of the first opening 70a is larger, more preferably 2 times or more, particularly 5 times. It is good to make it the above size. If it does so, it can control that the 1st opening part 70a becomes difficult to visually recognize under the influence of the inner wall of the 2nd opening part 70b, and it can control that an adhesive spreads just under the 1st opening part 70a. it can. Note that the second opening 70b does not need to be completely closed, and the measurement is performed by closing the range of five times the diameter of the first opening 70a around the center of the first opening 70a. The state can be stabilized. However, in order to suppress the intrusion of mist from the discharge hole surface 4-1, and to stabilize the measurement state more, it is better to completely block the mist.

  The position measuring unit 70 of the plate 4k may make a small hole in the plate 4k, make a larger hole in the plate 41, or close the hole with the plate 41. The position measuring unit 70 of the plate 4l only needs to make a small hole in the plate 4l. Note that these position measurement units 70 are not within the scope of the present invention.

  The piezoelectric actuator substrate 21 has a laminated structure composed of two piezoelectric ceramic layers 21a and 21b which are piezoelectric bodies. Each of these piezoelectric ceramic layers 21a and 21b has a thickness of about 20 μm. The thickness from the lower surface of the piezoelectric ceramic layer 21a of the piezoelectric actuator substrate 21 to the upper surface of the piezoelectric ceramic layer 21b is about 40 μm. Both of the piezoelectric ceramic layers 21 a and 21 b extend so as to straddle the plurality of pressure chambers 10. These piezoelectric ceramic layers 21a and 21b are made of, for example, a lead zirconate titanate (PZT) ceramic material having ferroelectricity.

  The piezoelectric actuator substrate 21 includes a common electrode 24 made of a metal material such as Ag—Pd and an individual electrode 25 made of a metal material such as Au. As described above, the individual electrode 25 includes the individual electrode main body 25a disposed at the position facing the pressurizing chamber 10 on the upper surface of the piezoelectric actuator substrate 21, and the extraction electrode 25b extracted therefrom. A connection electrode 26 is formed at a portion of one end of the extraction electrode 25 b that is extracted outside the region facing the pressurizing chamber 10. The connection electrode 26 is made of, for example, silver-palladium containing glass frit, and has a convex shape with a thickness of about 15 μm. The connection electrode 26 is electrically joined to an electrode provided in the signal transmission unit 92. Although details will be described later, a drive signal is supplied from the control unit 100 to the individual electrode 25 through the signal transmission unit 92. The drive signal is supplied in a constant cycle in synchronization with the conveyance speed of the print medium P.

  The common electrode 24 is formed over almost the entire surface in the region between the piezoelectric ceramic layer 21a and the piezoelectric ceramic layer 21b. That is, the common electrode 24 extends so as to cover all the pressurizing chambers 10 in the region facing the piezoelectric actuator substrate 21. The thickness of the common electrode 24 is about 2 μm. The common electrode 24 is connected to the surface electrode for the common electrode formed on the piezoelectric ceramic layer 21b so as to avoid the electrode group composed of the individual electrodes 25 through the via hole formed in the piezoelectric ceramic layer 21b, and is grounded. And held at the ground potential. The common electrode surface electrode is connected to another electrode on the signal transmission unit 92, similarly to the large number of individual electrodes 25.

  As will be described later, when a predetermined drive signal is selectively supplied to the individual electrode 25, the volume of the pressurizing chamber 10 corresponding to the individual electrode 25 changes, and the liquid in the pressurizing chamber 10 is pressurized. Is added. As a result, droplets are discharged from the corresponding liquid discharge ports 8 through the individual flow paths 12. That is, the portion of the piezoelectric actuator substrate 21 that faces each pressurizing chamber 10 corresponds to the individual displacement element 30 corresponding to each pressurizing chamber 10 and the liquid discharge port 8. That is, a displacement element 30, which is a piezoelectric actuator having a unit structure as shown in FIG. 5, is added to each pressurizing chamber 10 in a laminate composed of two piezoelectric ceramic layers 21 a and 21 b. The piezoelectric actuator substrate 21 includes a plurality of displacement elements 30 as pressurizing portions. The diaphragm 21a is located directly above the pressure chamber 10, is formed by a common electrode 24, a piezoelectric ceramic layer 21b, and individual electrodes 25. Yes. In the present embodiment, the amount of liquid ejected from the liquid ejection port 8 by one ejection operation is about 1.5 to 4.5 pl (picoliter).

  The large number of individual electrodes 25 are individually electrically connected to the control unit 100 via the signal transmission unit 92 and wiring so that the potential can be individually controlled. When an electric field is applied to the piezoelectric ceramic layer 21b in the polarization direction by setting the individual electrode 25 to a potential different from that of the common electrode 24, a portion to which the electric field is applied functions as an active portion that is distorted by the piezoelectric effect. In this configuration, when the control unit 100 sets the individual electrode 25 to a predetermined positive or negative potential with respect to the common electrode 24 so that the electric field and the polarization are in the same direction, a portion sandwiched between the electrodes of the piezoelectric ceramic layer 21b. (Active part) contracts in the surface direction. On the other hand, the piezoelectric ceramic layer 21a, which is an inactive layer, is not affected by an electric field, so that it does not spontaneously shrink and tries to restrict deformation of the active portion. As a result, there is a difference in strain in the polarization direction between the piezoelectric ceramic layer 21b and the piezoelectric ceramic layer 21a, and the piezoelectric ceramic layer 21b is deformed so as to protrude toward the pressurizing chamber 10 (unimorph deformation).

In an actual driving procedure in the present embodiment, the individual electrode 25 is set to a potential higher than the common electrode 24 (hereinafter referred to as a high potential) in advance, and the individual electrode 25 is temporarily set to the same potential as the common electrode 24 every time there is a discharge request. (Hereinafter referred to as a low potential), and then set to a high potential again at a predetermined timing. As a result, the piezoelectric ceramic layers 21a and 21b return to their original shapes at the timing when the individual electrode 25 becomes low potential, and the volume of the pressurizing chamber 10 increases compared to the initial state (the state where the potentials of both electrodes are different). To do. At this time, a negative pressure is applied to the pressurizing chamber 10 and the liquid is sucked into the pressurizing chamber 10 from the manifold 5 side. After that, at the timing when the individual electrode 25 is set to a high potential again, the piezoelectric ceramic layers 21 a and 21 b are deformed so as to protrude toward the pressurizing chamber 10. The pressure becomes positive and the pressure on the liquid rises, and droplets are ejected. That is, in order to discharge the droplet, a drive signal including a pulse based on a high potential is supplied to the individual electrode 25. The ideal pulse width is AL (Acoustic Length), which is the length of time during which the pressure wave propagates from the orifice 6 to the discharge hole 8. According to this, when the inside of the pressurizing chamber 10 is reversed from the negative pressure state to the positive pressure state, both pressures are combined, and the liquid droplets can be discharged at a stronger pressure.

  In gradation printing, gradation expression is performed by the number of droplets ejected continuously from the ejection holes 8, that is, the droplet amount (volume) adjusted by the number of droplet ejections. For this reason, the number of droplet discharges corresponding to the designated gradation expression is continuously performed from the discharge holes 8 corresponding to the designated dot region. In general, when liquid ejection is performed continuously, it is preferable that the interval between pulses supplied to eject liquid droplets is AL. As a result, the period of the residual pressure wave of the pressure generated when discharging the previously discharged liquid droplet coincides with the pressure wave of the pressure generated when discharging the liquid droplet discharged later, and these are superimposed. Thus, the pressure for discharging the droplet can be amplified. In this case, it is considered that the speed of the liquid droplets ejected later increases, but this is preferable because the landing points of a plurality of liquid droplets are close.

In the present embodiment, the laminated body used as the flow path member 4 of the liquid ejection head 2 has been described. However, the laminated body is similarly useful for other plate laminated bodies that may perform position measurement. . In the present embodiment, the displacement element 30 using piezoelectric deformation is shown as the pressurizing unit. However, the displacement element 30 is not limited to this, and can change the volume of the pressurizing chamber 10, that is, pressurizing. Any other device that can pressurize the liquid in the chamber 10 may be used. For example, the liquid in the pressurizing chamber 10 is heated and boiled to generate pressure, or MEMS (Micro Electro Mechanical Systems) is used. It may be a thing.

  Subsequently, another embodiment of the present invention will be described. 4B and 4C are partial longitudinal sectional views of the flow path member 4. The flow path member 4 and the liquid discharge head 2 manufactured using the flow path member 4 are basically the same as those described above. is there.

  In FIG. 4B, a first opening 170a, which is a through hole for measuring the position of the plate 4j, is provided, and the plate 4k has the first opening 170a at a position overlapping the first opening 170a. A recess 170d having a larger planar shape than the opening 170a is provided. Since the space is expanded under the first opening 170a by the concave portion 170d, the first opening 170a can be easily measured and the measurement accuracy can be increased similarly to the above-described position measuring unit 70.

  With this structure, the first opening 170a can be formed in the second plate 4k from the bottom, so that the position measuring unit can be formed in a layer below the position measuring unit 70. The concave portion 170d can be produced by, for example, half-etching or grinding. However, if the depth is the same at each position measuring portion, the measurement conditions can be made uniform and the measurement accuracy can be increased.

  In FIG. 4B, the plate 4j has a through-hole, the upper side is a first opening 270a for measuring the position, and the lower side is a position overlapping the first opening 270a. Thus, the second opening 270b has a larger planar shape than the first opening 170a. Since the second opening 270b has a structure in which a space is expanded under the first opening 270a, the first opening 270a is easy to measure and the measurement accuracy is also similar to the position measuring unit 70 described above. Can be high.

  With this structure, the first opening 270a can be formed in the second plate 4k from the bottom, so that the position measuring unit can be formed in a layer below the position measuring unit 70. In order to increase the measurement accuracy, it is preferable that there is no variation in the hole diameter. For that purpose, the through-hole is simply mortar-shaped and the first diameter is different from the diameter of the front and back of the through-hole. It is preferable that the opening 270a and the second opening 270b are stepped, and that the through hole on the first opening 270a side has a substantially constant hole shape. In such a case, the difference in planar shape between the first opening 270a and the second opening 270b can be increased. Such a through-hole can be produced by, for example, half etching or grinding.

  Compared with these two embodiments, in the first embodiment, the first opening 70a and the second opening 70b are simple through holes (diameter is substantially constant), so that the processing is simple. There are benefits. In order to take advantage of this advantage, the plate of the first embodiment is provided on a plate other than the second plate from the bottom, and the plate of the embodiment of FIG. 4B or 4C is provided on the second plate from the bottom. Also good.

  The liquid discharge head 2 is manufactured as follows, for example. A tape composed of a piezoelectric ceramic powder and an organic composition is formed by a general tape forming method such as a roll coater method or a slit coater method, and a plurality of green sheets that become piezoelectric ceramic layers 21a and 21b after firing are produced. . An electrode paste to be the common electrode 24 is formed on a part of the green sheet by a printing method or the like. Further, a via hole is formed in a part of the green sheet as necessary, and a via conductor is filled in the via hole.

  Next, each green sheet is laminated to produce a laminate, and pressure adhesion is performed. The laminated body after pressure contact is fired in a high-concentration oxygen atmosphere, and then the individual electrode 25 is printed on the fired body surface using an organic gold paste, fired, and then the connection electrode 26 is printed using an Ag paste. And the piezoelectric actuator board | substrate 21 is produced by baking.

  Next, the flow path member 4 is produced by laminating plates 4a to 4l obtained by a rolling method or the like via an adhesive layer. Holes to be the manifold 5, the individual supply flow path 14, the pressurizing chamber 10, the descender, and the like are processed in the plates 4a to 4l into a predetermined shape by etching.

  These plates 4a to 4l are preferably formed of at least one metal selected from the group consisting of Fe-Cr, Fe-Ni, and WC-TiC, particularly when ink is used as a liquid. Since it is desired to be made of a material having excellent corrosion resistance against ink, Fe-Cr is more preferable.

  The piezoelectric actuator substrate 21 and the flow path member 4 can be laminated and bonded through, for example, an adhesive layer. A well-known adhesive layer can be used as the adhesive layer, but in order not to affect the piezoelectric actuator substrate 21 and the flow path member 4, an epoxy resin or a phenol resin having a thermosetting temperature of 100 to 150 ° C. It is preferable to use at least one thermosetting resin adhesive selected from the group of polyphenylene ether resins. By heating to the thermosetting temperature using such an adhesive layer, the piezoelectric actuator substrate 21 and the flow path member 4 can be heat-bonded. After joining, a voltage is applied between the common electrode 24 and the individual electrode 25 to polarize the piezoelectric ceramic layer 21b in the thickness direction.

  Next, in order to electrically connect the piezoelectric actuator substrate 21 and the control circuit 100, a silver paste is supplied to the connection electrode 26, an FPC which is a signal transmission unit 92 on which a driver IC is mounted in advance is placed, and heat is applied. In addition, the silver paste is cured and electrically connected. The driver IC was mounted by electrically flip-chip connecting the FPC to the FPC with solder, and then supplying a protective resin around the solder and curing it.

  Subsequently, if necessary, the reservoir is bonded so that the liquid can be supplied from the opening 5a, the metal housing is screwed, and then the joint is sealed with a sealant, whereby the liquid discharge head 2 is Can be produced.

DESCRIPTION OF SYMBOLS 1 ... Printer 2 ... Liquid discharge head 2a ... Head main body 4 ... Flow path member 4a-1 ... (flow path member) plate 4-1 ... Discharge hole surface 4-2 ... Pressurizing chamber surface 5 ... Manifold 5a ... (manifold) opening 5b ... Sub-manifold 6 ... Squeeze 8 ... Discharge hole 10 ... Pressurizing chamber 12 ... Individual Channel 14: Individual supply channel 15 ... Partition 21 ... Piezoelectric actuator substrate 21a ... Piezoelectric ceramic layer (vibrating plate)
21b ... Piezoelectric ceramic layer 24 ... Common electrode 25 ... Individual electrode 25a ... Individual electrode body 25b ... Extraction electrode 26 ... Connection electrode 30 ... Displacement element (pressure part)
70 ... Position measuring unit 70a, 170a, 270a ... First opening 70b, 270b ... Second opening 70c, 170c, 270c ... Third opening 170d ... Recess 92 ... Signal transmission part

Claims (7)

At least three or more plates are laminated, and a laminated body having a position measuring unit,
When the position measuring unit uses the two stacked plates as a first plate and a second plate,
A first opening for measuring a position passing through the first plate;
A second opening penetrating the second plate, overlapping the first opening and having a larger planar shape than the first opening;
A laminate having the second opening and a part of the other plate laminated so as to close the opposite side of the first opening. At least two or more plates are laminated, and a laminated body having a position measuring unit,
When the position measuring unit uses the two stacked plates as a first plate and a second plate,
A first opening for measuring a position passing through the first plate;
The first plate has a concave portion that is provided on the first plate side of the second plate, overlaps with the first opening, and has a larger planar shape than the first opening. Laminated body. At least two or more plates are laminated, and a laminated body having a position measuring unit,
The position measuring unit is
A first opening for measuring a position of a through-hole penetrating one plate, which is open on one surface of the plate;
A second opening of the through hole opposite to the first opening, overlapping the first opening and having a larger planar shape than the first opening;
And a part of the other plate laminated so as to close the second opening. A liquid discharge head having the laminate according to any one of claims 1 to 3 and a plurality of pressure units,
The laminate has a plurality of discharge holes in the plate at the end in the stacking direction, and has a plurality of pressurizing chambers respectively connected to the plurality of discharge holes.
The plurality of pressurizing units can pressurize the plurality of pressurizing chambers, respectively.
The liquid discharge head according to claim 1, wherein the position measuring unit is arranged with the first opening facing a stacking direction opposite to the plate having the plurality of discharge holes.   Two or more of the plates having a plurality of the first openings of the alignment portion are stacked, and the positions of the centers of gravity of the first openings of the two or more plates coincide with each other. The liquid discharge head according to claim 4, wherein the liquid discharge head is provided.   A hole is opened from the first opening of the position measuring unit to the plate in the stacking direction opposite to the plate having the plurality of discharge holes so that the first opening can be seen. The liquid discharge head according to claim 4, wherein the liquid discharge head is provided.   A recording apparatus comprising: the liquid discharge head according to claim 4; a transport unit that transports a recording medium to the liquid discharge head; and a control unit that controls the liquid discharge head. apparatus.

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