JP2014087993A - Droplet discharge head, and image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a droplet discharge head and an image forming apparatus which can reduce deterioration of image quality due to temperature difference between liquids of individual liquid chambers while miniaturizing by mounting a drive circuit member.SOLUTION: The droplet discharge head includes a nozzle substrate formed with a nozzle array composed of a plurality of nozzles for discharging liquid droplets, a plurality of individual liquid chambers which respectively communicate with respective nozzles and are formed along the nozzle array direction to store the liquid, a pressure generating means for boosting the pressure in the individual liquid chambers, a drive circuit member for transmitting a drive signal to the pressure generating means, a common liquid chamber which communicates with each individual liquid chamber and stores the liquid to be supplied to each individual liquid chamber, and a supply hole formed substrate which forms one wall surface of the common liquid chamber and in which a supply hole for supplying the liquid to the common liquid chamber is formed. There are provided two or more partition walls which are positioned in the individual liquid chamber side of the common liquid chamber, formed along the nozzle array direction, and partitions an inner part of a supply liquid chamber. The liquid in a region partitioned by the partition wall in the common liquid chamber is supplied to at least one individual liquid chamber.

Description

  The present invention relates to a droplet discharge head such as an inkjet head that discharges droplets, and an image forming apparatus including the droplet discharge head.

  This type of droplet discharge head is used as a recording head of an image forming apparatus such as a copying machine, a printer, a facsimile machine, or a plotter. The image forming apparatus here forms an image on a recording material, but the material of the recording material is not limited to paper, and is a thread, fiber, fabric, leather, metal, plastic, glass, It means an apparatus for forming an image by discharging a liquid onto any recording material such as wood or ceramics. Image formation not only applies an image having a meaning such as a character or a figure to a recording material, but also applies an image having no meaning such as a pattern to the recording material (simply ejects a droplet). ) Also means.

  The liquid ejected as droplets is not limited to so-called ink, and is not particularly limited as long as it becomes liquid when ejected, and includes, for example, DNA samples, resists, pattern materials, and the like. It is. Therefore, it is used not only for so-called image printing, but also for three-dimensional molding technology using the ink jet technology and blood drip.

  As one of the image forming apparatuses, ink droplets are ejected from the inkjet head while reciprocating a carriage on which the inkjet head, which is a droplet ejection head, is mounted. An ink jet printer that forms an image pattern by landing ejected ink droplets on a recording material is known.

  The inkjet head includes a nozzle substrate on which a nozzle array composed of a plurality of nozzles for ejecting ink droplets is formed, and a plurality of individual liquid chambers that communicate with each nozzle and that are formed along the direction of the nozzle array and contain ink. And have. Also, pressure generating means for increasing the pressure in the individual liquid chamber, a common liquid chamber that is long in the direction of the nozzle row that communicates with each individual liquid chamber and stores ink to be supplied to the individual liquid chamber, and one wall surface of the common liquid chamber And a supply hole forming substrate provided with ink supply holes for supplying ink to the common liquid chamber. Then, the ink sent from the external ink tank is supplied to the common liquid chamber via the ink supply holes, and is supplied from the common liquid chamber to the nozzles provided on the nozzle plate via the individual liquid chambers. Yes.

  Recently, on-demand ink jet printers configured to eject ink droplets only when recording is required have become mainstream. An ink jet head is mounted on this on-demand ink jet printer. As this ink jet head, there is a piezoelectric type in which the pressure in the individual liquid chamber is increased by the displacement of a piezoelectric element as pressure generating means provided in the individual liquid chamber, and ink is ejected from the nozzle. In this method, a piezoelectric element that is pressure generating means is driven by a drive signal from a drive IC chip that is a drive circuit member, and ink droplets are ejected from nozzles to land on a recording material.

  In recent years, there has been an increasing demand for miniaturization of inkjet heads. As one method for meeting this requirement, a configuration in which a driving IC chip is mounted on an ink jet head has been proposed (Patent Document 1, etc.).

  However, when a driving IC chip is provided in an ink jet head, the driving IC chip generates heat and becomes high temperature as it is driven, which may affect image quality. Specifically, the drive IC chip generates heat, and the heat is transmitted to the ink, whereby the viscosity of the ink changes and the ejection behavior from the nozzles fluctuates. Furthermore, since the ink is supplied to the individual liquid chambers from the side closer to the ink supply hole in the longitudinal direction of the common liquid chamber, heat can be transferred to the individual liquid chambers farther away from the ink supply hole in the longitudinal direction of the common liquid chamber. The time is long and the total amount of heat transferred to the ink increases. Accordingly, the temperature of the ink is higher when it is away from the ink supply hole in the longitudinal direction of the common liquid chamber, and the temperature of the ink is different for each individual liquid chamber disposed along the longitudinal direction of the common liquid chamber. For this reason, the discharge behavior from the nozzles is different for each individual liquid chamber, and printing unevenness or the like occurs, thereby degrading the image quality.

  The present invention has been made in view of the above problems, and its object is to reduce a reduction in image quality due to a temperature difference of liquid between individual liquid chambers while mounting a drive circuit member to reduce the size. It is an object to provide a droplet discharge head that can be used, and an image forming apparatus including the droplet discharge head.

  In order to achieve the above object, the invention according to claim 1 is formed along a nozzle row direction in which each nozzle nozzle communicates with a nozzle substrate formed with a plurality of nozzles for discharging droplets. A plurality of individual liquid chambers for storing liquid, pressure generating means for increasing the pressure in the individual liquid chambers, drive circuit members for sending drive signals to the pressure generating means, and individual liquids communicating with the individual liquid chambers. A liquid discharge unit comprising: a common liquid chamber for storing a liquid to be supplied to the chamber; and a supply hole forming substrate in which a supply hole for forming a wall of the common liquid chamber and supplying the liquid to the common liquid chamber is formed. The head has at least two or more partition walls that are on the individual liquid chamber side of the common liquid chamber and that are arranged along the nozzle row direction and partition the supply liquid chamber, There is little liquid in the area defined by the partition walls. It is characterized in that Kutomo one or more of said supplied to the individual liquid chamber.

  In the present invention, by providing the partition in the supply liquid chamber, the time required for the liquid supplied from the supply hole to the common liquid chamber to reach the individual liquid chamber and the difference in the amount of heating received are small between the individual liquid chambers. Thus, a path in the common liquid chamber from the supply hole to each individual liquid chamber can be formed. Thereby, the temperature difference of the liquid which reached each individual liquid chamber between individual liquid chambers can be made small. Therefore, it is possible to reduce the deterioration of image quality due to the temperature difference of the liquid between the individual liquid chambers.

  As described above, according to the present invention, there is an excellent effect that it is possible to reduce the deterioration of the image quality due to the temperature difference of the liquid between the individual liquid chambers while mounting the drive circuit member to reduce the size.

Sectional drawing which follows the B-B 'line of FIG. 1 is a perspective view illustrating an image forming apparatus according to an embodiment. 1 is a schematic configuration diagram illustrating an image forming apparatus. 1 is an exploded perspective view of an inkjet head according to Embodiment 1. FIG. Sectional drawing which follows the A-A 'line of FIG. The figure which showed the temperature of the ink in the cross section which follows the C-C 'line | wire of FIG. FIG. 6 is a cross-sectional view of an inkjet head according to a second embodiment.

Hereinafter, an embodiment of an image forming apparatus to which the present invention is applied will be described.
FIG. 2 is a perspective view illustrating the image forming apparatus 100 according to the embodiment. FIG. 3 is a schematic configuration diagram showing the image forming apparatus 100.

  The image forming apparatus 100 is provided with a printing mechanism unit 134. The printing mechanism unit 134 is provided with a carriage 131 that can move in the main scanning direction, which is a direction orthogonal to the conveyance direction of the paper 135 as a recording material, inside the apparatus main body. An ink jet head 132 mounted on the carriage 131 and an ink cartridge 133 for supplying ink to the ink jet head 132 are also provided.

  In the lower part of the main body of the image forming apparatus, a paper feed cassette 106 capable of stacking a large number of sheets 135 from the front side can be detachably mounted. Further, the manual feed tray 137 for manually feeding the paper 135 can be turned over. The paper 135 sent out from the paper feed cassette 106 or the manual feed tray 137 is transported to a position facing the printing mechanism unit 134 to record an image, and then discharged to a paper discharge tray 108 mounted on the rear side. .

  The printing mechanism unit 134 holds the carriage 131 slidably in the main scanning direction with a main guide rod 109 and a sub guide rod 110 which are guide members horizontally mounted on left and right side plates (not shown). An ink jet head 132 that discharges ink droplets of each color of yellow (Y), cyan (C), magenta (M), and black (K) is mounted on the carriage 131. The inkjet head 132 includes a plurality of nozzles (ink ejection ports) arranged in a direction orthogonal to the main scanning direction, and is mounted on the carriage 131 in a posture in which these nozzles face downward in the vertical direction.

  Four ink cartridges 133 for individually supplying Y, M, C, and K inks to the inkjet head 132 are detachably mounted on the carriage 131. At the upper part of the ink cartridge 133, an air outlet communicating with the atmosphere is provided. In addition, a supply hole for supplying ink to the inkjet head 132 is provided below the ink cartridge 133. In addition, a porous body filled with ink is provided inside the ink cartridge 133. The ink in the porous body is slightly negative pressure due to the capillary force of the porous body.

  In the image forming apparatus according to the embodiment, as the inkjet head 132, one that ejects ink of each color with one head is used, but a plurality of heads corresponding to each color may be used. The carriage 131 is slidably fitted on the rear side (downstream side in the paper conveyance direction) by the main guide rod 109, and is slidably mounted on the front side (upstream side in the paper conveyance direction) by the sub guide rod 110. ing. In order to move and scan the carriage 131 in the main scanning direction, a timing belt 114 is stretched between a driving pulley 112 and a driven pulley 113 that are rotationally driven by a main scanning motor 111. The timing belt 114 mounted on the carriage 131 moves endlessly by forward and reverse rotation of the main scanning motor 111, whereby the carriage 131 is driven to reciprocate.

  The sheet 135 set in the sheet feeding cassette 106 is conveyed below the inkjet head 132. For this purpose, a paper feed roller 115, a friction pad 116, a guide member 117, a transport roller 118, a transport roller 119, a leading end roller 120, and the like are provided. The paper feed roller 115 and the friction pad 116 are for feeding the paper 135 from the paper feed cassette 106 or separating it into one sheet. The guide member 117 is for guiding the fed sheet 135 toward the feeding destination. The transport roller 118 is for reversing and transporting the fed paper 135. Further, the transport roller 119 is pressed against the peripheral surface of the transport roller 118. Further, the leading end roller 120 defines the feed angle of the sheet 135 from the transport roller 118.

  The transport roller 118 is rotationally driven by a sub-scanning motor 121 through a gear train. The paper 135 sent out from the transport roller 118 corresponding to the movement range of the carriage 131 in the main scanning direction is guided below the ink jet head 132 by the printing receiving member 122. On the downstream side of the printing receiving member 122 in the paper conveyance direction, a conveyance roller 123 and a spur 124 that are rotationally driven to send out the paper 135 in the paper discharge direction are provided. Further, a discharge roller 125 and a spur 126 for sending the sheet 135 to the discharge tray 108, guide members 127 and 128 for forming a discharge path, and the like are also provided.

  At the time of recording, the inkjet head 132 is driven according to the image signal while moving the carriage 131, thereby ejecting ink onto the stopped sheet 135 to record one line. Record the line. Upon receiving a recording end signal or a signal that the trailing edge of the sheet 135 has reached the recording area, the recording operation is terminated and the sheet 135 is discharged.

  A recovery device 129 for recovering the ejection failure of the inkjet head 132 is disposed at a position outside the recording area on the right end side in the movement direction of the carriage 131. The recovery device 129 includes a cap unit, a suction unit, and a cleaning unit. The carriage 131 is moved to the recovery device 129 side during printing standby, and the inkjet head 132 is capped by the capping unit, and the ejection port portion is kept in a wet state to prevent ejection failure due to ink drying. Further, by ejecting ink that is not related to recording during recording or the like, the ink viscosity of all the ejection ports is made constant and stable ejection performance is maintained.

[Example 1]
FIG. 4 is an exploded perspective view of the inkjet head 132 according to the first embodiment. FIG. 5 is a cross-sectional view taken along the line AA ′ of FIG. 1 is a cross-sectional view taken along line BB ′ of FIG.

  Referring to FIG. 4, the inkjet head 132 includes the nozzle plate 2, the individual liquid chamber forming substrate 101, the actuator substrate 14, the protective substrate 102, the common liquid chamber forming substrate 103, and the manifold 104, and the thickness direction of the inkjet head 132. Are stacked in order.

  The nozzle plate 2 includes a nozzle row 10y made up of a plurality of nozzles 1y, a nozzle row 10m made up of a plurality of nozzles 1m, a nozzle row 10c made up of a plurality of nozzles 1c, and a nozzle row 10k made up of a plurality of nozzles 1k. It is the nozzle substrate formed in this.

  The individual liquid chamber forming substrate 101 includes a plurality of individual liquid chambers 3y, 3m, 3c, and 3k that are connected to the nozzles 1y, 1m, 1c, and 1k and store the ink along the nozzle row direction. is there.

  The actuator substrate 14 includes actuators 15y, 15m, 15c, and 15k that are pressure generating means for increasing the pressure in each individual liquid chamber 3, and drive IC chips 105a and 105b that are drive circuit members that output ejection signals to the actuators 15. Is provided. In addition, a wiring member that electrically connects each actuator 15 and the drive IC chips 105a and 105b is also provided.

  The protective substrate 102 protects the actuators 15y, 15m, 15c, and 15k.

  The common liquid chamber forming substrate 103 is formed with long common liquid chambers 4y, 4m, 4c, and 4k formed in the direction of the nozzle row that communicates with the individual liquid chambers 3 and stores ink to be supplied to the individual liquid chambers 3. It is. Further, in each common liquid chamber 4, a supply liquid chamber is provided along the common liquid chamber longitudinal direction which is on the individual liquid chamber 3 side in the common liquid chamber 4 in the thickness direction and is in the same direction as the nozzle row direction. There are at least two partition members 201y, 201m, 201c, and 201k that are partition walls that divide the interior of 4.

  The manifold 104 is a supply hole forming substrate in which one wall surface of the common liquid chambers 4y, 4m, 4c and 4k is formed and supply holes 107y, 107m, 107c and 107k for supplying ink to the common liquid chambers 4 are formed. is there.

  Referring to FIG. 5, ink is supplied from the ink cartridge 133 shown in FIG. 3 to the common liquid chambers 4y, 4m, 4c, and 4k through the supply holes 107y, 107m, 107c, and 107k. The ink supplied to the common liquid chambers 4y, 4m, 4c, and 4k is further distributed to the individual liquid chambers 3y, 3m, 3c, and 3k, and nozzles 1y, 1m, 1c, and 1k are provided by the actuators 15y, 15m, 15c, and 15k. It is discharged from.

  The actuators 15y, 15m, 15c, and 15k are provided on a diaphragm (not shown) on the lower electrodes 11y, 11m, 11c, and 11k, the piezoelectric elements 12y, 12m, 12c, and 12k, and the upper electrodes 13y, 13m, 13c, and 13k. It is an electromechanical conversion element comprised from this.

  Further, the upper electrode 13 of the actuator 15 is connected to an individual electrode wiring (not shown) provided on the actuator substrate 14, and the lower electrode 11 of the actuator 15 is connected to a common electrode wiring (not shown) provided on the actuator substrate 14. Yes. The driving IC chip 105 is connected to the individual electrode wiring and the common electrode wiring, so that the actuator 15 is electrically connected to the driving IC chip 105 via the individual electrode wiring and the common electrode wiring. .

  When the actuator 15 (consisting of the lower electrode 11, which is a common electrode, the piezoelectric element 12, and the upper electrode 13 which is an individual electrode) is driven in a state where the individual liquid chamber 3 is filled with ink, the nozzle 1 is driven. More ink droplets are ejected. Specifically, a potential having a predetermined driving waveform is applied between the upper electrode 13 and the lower electrode 11 of the actuator 15. As a result, the piezoelectric element 12 contracts, and the entire diaphragm, which is a portion in close contact with the piezoelectric element 12 with the lower electrode 11 interposed therebetween, is deformed into a convex shape toward the individual liquid chamber 3 side. Due to this deformation, the volume of the individual liquid chamber 3 decreases, the pressure in the individual liquid chamber 3 rapidly increases, and ink droplets are ejected from the nozzle 1 toward the paper.

  As shown in FIG. 1, a plurality of partition members 201y are provided in the common liquid chamber 4y in the longitudinal direction of the common liquid chamber, and are partitioned (partitioned) by the partition members 201y in the common liquid chamber 4y. The ink is supplied to at least one individual liquid chamber 3y. The partition member 201y is provided on the side of the protective substrate 102 where the amount of heat transferred to the ink in the common liquid chamber 4y is large, and the lower end of the partition member 201y extends to the vicinity of the individual liquid chamber 3y.

  The ink in the region partitioned by the partition member 201y in the supply liquid chamber 4y moves in the Z1 direction as the ink in the individual liquid chamber 3y decreases each time ink is ejected. As a result, since ink is always supplied in the Z1 direction of the common liquid chamber 4y to the area partitioned by the partition member 201y in the supply liquid chamber 4y, the ink in the partitioned area is partitioned by another partition member 201y. It does not move to the specified area.

  In addition, the lower end of the partition member 201y may not be in contact with the individual liquid chamber forming substrate 101 and the protective substrate 102, and the individual liquid chambers 3 in adjacent regions partitioned by the partition member 201y in the supply liquid chamber 4y. The sides may be in communication. Even if there is a communication portion that communicates such adjacent regions, supplying ink to the individual liquid chamber 3y without passing through this communication portion supplies ink to the adjacent partitioned region through the communication portion. The flow path resistance is smaller than that. Therefore, most of the ink that is partitioned by the partition member 201y and is supplied from one of the adjacent regions to the individual liquid chamber is not supplied from the communicating portion to the other region, and does not pass through the communicating portion. The liquid is supplied to the individual liquid chamber 3y.

  Thus, since the lower end of the partition member 201y does not have to be in contact with the individual liquid chamber forming substrate 101 and the protective substrate 102, the partition member 201y, the individual liquid chamber forming substrate 101, and the protective substrate 102 are manufactured. It becomes easy and the yield at the time of manufacture improves.

  FIG. 6 is a diagram showing the temperature of ink in a cross section taken along the line C-C ′ in FIG. 1, and the ink flow is from left to right in FIG. 6.

  As shown in FIG. 6, the temperature of the ink in the supply liquid chamber 4y hardly rises until it reaches the area partitioned by the partition member 201y in the supply liquid chamber 4y. Thereafter, the temperature rises as it approaches the protective substrate 102 side of the region partitioned by the partition member 201y in the supply liquid chamber 4y. Therefore, since the temperature of the ink in the supply liquid chamber 4y rises in this way, the variation in the ink temperature among the individual liquid chambers 3y is caused by heating in the region partitioned by the partition member 201y in the supply liquid chamber 4y. Variations in temperature rise.

  In addition to the ejection of ink that contributes to normal image formation, by performing an idle ejection operation that ejects ink that does not contribute to image formation at a predetermined timing, partitioning is performed by the partition member 201y in the supply liquid chamber 4y. The ink in the designated area is replaced with new ink. For this reason, even if the temperature difference of the ink has arisen in the area | region partitioned by the partition member 201y in the supply liquid chamber 4y because the frequency | count of discharge for every nozzle differs, this idle discharge operation can eliminate. Thereby, the dispersion | variation in the temperature of the area | region partitioned by the partition member 201y can be kept below a fixed temperature.

  From the above, when there is no partition member 201y in the supply liquid chamber 4y, that is, when the temperature of the ink supplied to the individual liquid chamber 3y is affected by the heating on the upstream side in the Z1 direction, the individual liquid chamber 3y. Variation in ink temperature between the two becomes smaller. Therefore, it is possible to reduce image quality deterioration due to uneven printing due to the ink temperature difference between the individual liquid chambers 3.

[Example 2]
FIG. 7 is a cross-sectional view of the ink jet head 132 according to the second embodiment, and corresponds to a cross section taken along the line BB ′ of FIG.

  As shown in FIG. 7, the interval between the adjacent partition members 201y is wider at a position away from the supply hole 107 in the common liquid chamber longitudinal direction (X1 direction and X2 direction) than in the vicinity of the supply hole 107y. Yes. Further, the number of the individual liquid chambers 3y between the adjacent partition members 201y is also more distant from the supply holes 107 in the common liquid chamber longitudinal direction (X1 direction and X2 direction) than in the vicinity of the supply holes 107y. . Further, the length of the partition member 201y in the Z2 direction is shorter at a position away from the supply hole 107 in the common liquid chamber longitudinal direction (X1 direction and X2 direction) than in the vicinity of the supply hole 107y.

  In this embodiment, in the region partitioned by the partition member 201y in the vicinity of the supply hole 107y in the supply liquid chamber 4y, the ink flows with a narrow width and a long distance. In addition, the average flow rate in the region partitioned by the partition member 201y becomes substantially constant because the number of individual liquid chambers 3y that supply ink decreases as the interval between the adjacent partition members 201 decreases. When the average flow velocity is the same, the channel resistance increases as the distance between adjacent partition members 201y is narrower and the flowing distance is longer. For this reason, the channel resistance in the region partitioned by the partition member 201 is larger in the vicinity of the supply hole 107y than in a position away from the supply hole 107 in the common liquid chamber longitudinal direction (X1 direction and X2 direction).

  In contrast, up to the region partitioned by the partition member 201y in the supply liquid chamber 4y, the vicinity of the supply hole 107y is more than the position away from the supply hole 107 in the common liquid chamber longitudinal direction (X1 direction and X2 direction). Ink flows a short distance in the Z1 direction. Therefore, the flow resistance to the region partitioned by the partition member 201y in the supply liquid chamber 4y is a position in the vicinity of the supply hole 107y farther from the supply hole 107 in the common liquid chamber longitudinal direction (X1 direction and X2 direction). Smaller than.

  For this reason, the flow path resistance difference to each individual liquid chamber 3y can be reduced by appropriately adjusting the length of the partition member 201y and the interval between the adjacent partition members 201y.

  Thus, by reducing the flow path resistance difference to each individual liquid chamber 3y, it is possible to reduce discharge variation due to insufficient ink supply during high repetition discharge, and from the supply hole 107 in the common liquid chamber longitudinal direction (X1 direction and X2 direction). It is possible to reduce the risk of remaining bubbles at a distant position.

  As described above, by providing the partition member 201 in the supply liquid chamber 4, the time required for the ink supplied from the supply hole 107 to the common liquid chamber 4 to reach the individual liquid chamber 3 and the difference in the amount of heating received. The path in the common liquid chamber 4 can be formed so that the value becomes smaller between the individual liquid chambers. Thereby, the temperature difference of the ink which reached | attained each separate liquid chamber 3 between individual liquid chambers can be made smaller than the case where the partition member 201 is not provided in the supply liquid chamber 4. FIG. Therefore, it is possible to reduce the degradation of the image quality due to the printing unevenness due to the ink temperature difference between the individual liquid chambers.

  In the above embodiment, the case where the present invention is applied to an ink jet head having a four-color integrated form has been described. However, the present invention can also be applied to one or more colors and an arbitrary number of ink jet heads.

What has been described above is merely an example, and the present invention has a specific effect for each of the following modes.
(Aspect A)
A nozzle substrate such as a nozzle plate 2 on which a nozzle row such as a nozzle row 10 composed of a plurality of nozzles 1 and the like that eject droplets such as ink droplets is formed, and communicates with each nozzle along the direction of the nozzle row. The formed individual liquid chambers such as a plurality of individual liquid chambers 3 that contain liquid such as ink, pressure generating means such as an actuator 15 for boosting the individual liquid chambers, and a drive signal to the pressure generating means. Drive circuit members such as drive IC chips 105a and 105b to be sent, a common liquid chamber such as a common liquid chamber 4 that communicates with each individual liquid chamber and contains a liquid to be supplied to each individual liquid chamber, and one wall surface of the common liquid chamber And a liquid discharge head such as an ink jet head 132 provided with a supply hole forming substrate such as a manifold 104 and a supply hole such as a supply hole 107 for supplying a liquid to the common liquid chamber. And having at least two partition walls such as a partition member 201 which is disposed along the nozzle row direction and divides the supply liquid chamber, on the individual liquid chamber side of the common liquid chamber, A liquid in a region partitioned by the partition in the chamber is supplied to at least one of the individual liquid chambers. According to this, as described in the above embodiment, it is possible to reduce the deterioration in image quality due to the temperature difference of the liquid between the individual liquid chambers while mounting the drive circuit member to reduce the size.
(Aspect B)
In (Aspect A), the individual liquid chamber forming substrate such as the individual liquid chamber forming substrate 101 that forms the individual liquid chamber, the pressure generating unit, the pressure generating unit, and the drive circuit member are electrically connected to each other. An actuator substrate such as an actuator substrate 14 provided with wiring members such as electrode wiring and common electrode wiring, a protective substrate such as a protective substrate 102 that protects the pressure generating means, and the common liquid chamber together with the supply hole forming substrate A common liquid chamber forming substrate such as a common liquid chamber forming substrate 103, and the nozzle substrate, the individual liquid chamber forming plate, the actuator substrate, the protective substrate, the common liquid chamber forming substrate, and the supply hole. A formation substrate is sequentially stacked. According to this, as described in the above embodiment, the drive circuit member that is a heat generation source and the common liquid chamber are close to each other, and even if the structure is such that heat is easily transferred to the liquid in the common liquid chamber, Printing unevenness due to the temperature difference of the liquid can be reduced.
(Aspect C)
In (Aspect A) or (Aspect B), the individual liquid chamber sides of adjacent regions partitioned by the partition walls in the supply liquid chamber communicate with each other. According to this, as described in the above embodiment, since there is a gap, it is easy to manufacture and the yield during manufacturing is improved.
(Aspect D)
In (Aspect A), (Aspect B), or (Aspect C), the length of the partition is shorter as the distance from the supply hole is longer in the nozzle row direction. According to this, as described in the above embodiment, since the flow resistance difference to each individual liquid chamber can be reduced, discharge variation due to insufficient liquid supply at the time of high repeated discharge and bubble remaining on the downstream side are reduced. it can.
(Aspect E)
In (Aspect A), (Aspect B), (Aspect C), or (Aspect D), the interval between the adjacent partition walls in the nozzle row direction increases as the distance from the supply hole increases in the nozzle row direction. According to this, as described in the above embodiment, since the flow path resistance difference to each individual liquid chamber can be reduced, ejection variation due to insufficient ink supply at the time of high repeated ejection and bubbles on the downstream side remain. Risk can be reduced.
(Aspect F)
In (Embodiment E), the number of the individual liquid chambers between adjacent partition walls increases as the distance from the supply hole increases in the nozzle row direction. According to this, as described in the above embodiment, since the flow path resistance difference to each individual liquid chamber can be reduced, ejection variation due to insufficient ink supply at the time of high repeated ejection and bubbles on the downstream side remain. Risk can be reduced.
(Aspect G)
In an image forming apparatus such as the image forming apparatus 100 for forming an image by transporting a recording material such as a sheet 135 to a recording material by attaching droplets ejected by a droplet ejecting means to the recording material (as the droplet ejecting means ( The droplet discharge head of Aspect A), (Aspect B), (Aspect C), (Aspect E) or (Aspect F) was used. According to this, as described in the above embodiment, discharge variation due to heat generation is reduced, so that stable image formation can be performed.
(Aspect H)
In (Aspect G), an empty ejection operation for ejecting droplets that do not contribute to image formation from the droplet ejection head is performed at a predetermined timing. According to this, as described in the above embodiment, the temperature of the ink in the region partitioned by the partition can be kept within a certain temperature range.

DESCRIPTION OF SYMBOLS 1 Nozzle 2 Nozzle plate 3 Individual liquid chamber 4 Common liquid chamber 10 Nozzle row 11 Lower electrode 12 Piezoelectric element 13 Upper electrode 14 Actuator substrate 15 Actuator 100 Image forming apparatus 101 Individual liquid chamber formation substrate 102 Protection substrate 103 Common liquid chamber formation substrate 104 Manifold 105a Drive IC chip 105b Drive IC chip 106 Paper feed cassette 107 Supply hole 108 Paper discharge tray 109 Main guide rod 110 Subordinate guide rod 111 Main scan motor 112 Drive pulley 113 Driven pulley 114 Timing belt 115 Paper feed roller 116 Friction pad 117 Guide Member 118 Conveying roller 119 Conveying roller 120 Leading end roller 121 Sub-scanning motor 122 Printing receiving member 123 Conveying roller 124 Spur 125 Discharge roller 126 Spur 127 Id member 128 guide member 129 recovery device 131 carriage 132 inkjet head 133 ink cartridge 134 printing mechanism unit 135 sheet 137 bypass tray 201 partition member

JP 2010-179609 A

Claims (8)

A nozzle substrate on which a nozzle row composed of a plurality of nozzles for discharging droplets is formed;
A plurality of individual liquid chambers that contain liquids and that are formed along the nozzle row direction in communication with the nozzles,
Pressure generating means for increasing the pressure in the individual liquid chamber;
A drive circuit member for sending a drive signal to the pressure generating means;
A common liquid chamber that communicates with each individual liquid chamber and contains a liquid to be supplied to each individual liquid chamber;
In a liquid droplet ejection head comprising a supply hole forming substrate having a supply hole for forming a wall surface of the common liquid chamber and supplying a liquid to the common liquid chamber,
At least two partition walls which are on the individual liquid chamber side of the common liquid chamber and which are arranged along the nozzle row direction and partition the supply liquid chamber;
A liquid droplet ejection head, wherein a liquid in a region defined by the partition in the common liquid chamber is supplied to at least one of the individual liquid chambers. The droplet discharge head according to claim 1.
An individual liquid chamber forming substrate for forming the individual liquid chamber;
An actuator substrate provided with the pressure generating means, and a wiring member for electrically connecting the pressure generating means and the drive circuit member;
A protective substrate for protecting the pressure generating means;
A common liquid chamber forming substrate that forms the common liquid chamber together with the supply hole forming substrate;
The droplet discharge head, wherein the nozzle substrate, the individual liquid chamber forming substrate, the actuator substrate, the protective substrate, the common liquid chamber forming substrate, and the supply hole forming substrate are stacked in order. The droplet discharge head according to claim 1 or 2,
A liquid droplet ejection head, wherein the individual liquid chamber sides of adjacent regions partitioned by the partition walls in the supply liquid chamber communicate with each other. The droplet discharge head according to claim 1, 2 or 3,
The droplet discharge head according to claim 1, wherein a length of the partition wall is shorter as it is away from the supply hole in the nozzle row direction. The droplet discharge head according to claim 1, 2, 3, or 4
A liquid droplet ejection head, wherein an interval between adjacent partition walls in the nozzle row direction is wider as the distance from the supply hole is longer in the nozzle row direction. The droplet discharge head according to claim 5.
The liquid droplet ejection head, wherein the number of the individual liquid chambers between adjacent partition walls increases as the distance from the supply hole increases in the nozzle row direction. In an image forming apparatus for forming an image by adhering droplets ejected by droplet ejection means to the recording material while conveying the recording material,
An image forming apparatus using the droplet discharge head according to claim 1, 2, 3, 4, 5, or 6 as the droplet discharge means. The image forming apparatus according to claim 7.
An image forming apparatus, wherein an empty discharge operation for discharging droplets that do not contribute to image formation from the droplet discharge head is performed at a predetermined timing.

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